Variance Unocal Corporation (Derita)( GW Incident # 3751) V6

':.JAMES B. Hu NTclri ... ,·
· Goytp;~l)IOR
'WAYNE MCDEVlff
SECRETARY
A. PRESToNftOWARD,
;(\
JR., P.E.
DIRECTOR
,,,, NORTH CAROLINA DEPARTMENT OF
ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
March 16, 1998
CERTIFIED MAIL NUMBER: P 068 139 041
Mr. Richard G. Horne, P.E.
Uno cal Corporation
Diversified Business Group
P.O. Box 4147
Atlanta, GA 30329
Subject: Request for Variance from Groundwater Quality
Standards in 15A NCAC 2L .0202 and
Corrective Action in 15A NCAC 2L .01060) for
the Unocal Corporation at 2932 Gibbon Road in
Charlotte, North Carolina {Groundwater Incident
# 3751 }.
This is to inform you that the Environmental Management Commission, at
their March 12, 1998 meeting, approved the variance request by the Unocal
Corporation for property it formerly owned at 2932 Gibbon Road in Derita
Community of Charlotte, North Carolina. The Commission granted this variance
without the requirement that the Unocal Corporation conduct additional monitoring.
The Commission's waiver of monitoring was based on information in the variance
request demonstrating the effectiveness of remediation efforts, the cost incurred by the
company, the results of monitoring showing no significant increase in substances at
this site when cleanup operations were suspended, the comment received and interest
level from the public who were provided advanced notice of the public hearing, and
the lack of impact the site has on water supply wells.
GROUNDWATER Sl!CTION
P.O BOX 29578, RALEIGH, NC 27626•0578 • 2728 CAPITAL BLVD., RALEIGH, NC, 2.j7604
PHONE 919·733-3221 FAX 919-71 s-bsa5
AN EqUAL OPPORTUNITY/ AFFIRMATIVE ACTION EMPLOYER• 50% RECYCLED/I 0% POST·CONSUMER PAPER
Please note that approval of this variance by the Environmental Management
Commission represents final action on this request pursuant to the requirements of
15A NCAC 2L .0113. If you need to discuss this letter further, please feel free to
contact me at [phone].
Sincerely,
~~7
Arthur Mouberry, P.E.,
cc: Preston Howard
Arthur Mouberry
Groundwater Section Assistant Chiefs
Tom Warburton
Mooresville Regional Groundwater
Stewart Hines (S&ME, Inc)
Chief, Groundwater
Section
Tommy Stevens
Jennie Odette
Allen Schiff
Dr. Ken Rudo
David Hance
Ernie Seneca
2
TIME
10:00
10:1S
10:30
12:30
2:00
3:00
3:1S
3:30
5:30
6:45
GROUNDWATER SUPERVISORS' MEETING
FAYETTEVILLE, NORTH CAROLINA , SLEEP INN
HIGHWAY 53 & INTERSTATE 95, SOUTHWESTERN CONFERENCE ROOM
FEBRUARY 4, 1998 THROUGH FEBRUARY 5, 1998
TOPIC OF DISCUSSION
WEDNESDAY, FEBRUARY 4, 1998
ARRIVAL & SETUP
STAFF INTRODUCTIONS AND GREETINGS
IMPLEMENTATION OF RISK BASED RULES
1) Status Update
2) Policy for Implementation of RBCA
3) Follow-up Training
4) Technical Questions
L*U*N*C*H
DISCUSSION OF REGIONAL ISSUES
B*R*E*A*K
STATUS OF DRAFT CHANGES TO WELL CONSTRUCTION
RULES
CONTINUE THE DISCUSSION OF REGIONAL ISSUES
ADJOURN FOR DINNER
~
POSSIBL~ EVENING SESSION (if needed)
Page 1 of 3
DISCUSSION
LEADER
Bush
Boshoff
Mouberry
Boshoff
Reid/Strauss
R.O . Supervisors
(in rotation)
Cheek
R.O. Supervisors
(in rotation)
SMT2-98 .XCL
TIME
8:30
8:45
9:00
9:30
10:30
10:45
11:00
11:30
11:45
1:00
2:30
2:45
4:30
GROUNDWATER SUPERVISORS' MEETING
FAYETTEVILLE, NORTH CAROLINA, SLEEP INN
HIGHWAY 53 & INTERSTATE 95, SOUTHWESTERN CONFERENCE ROOM
FEBRUARY 4, 1998 THROUGH FEBRUARY 5, 1998
TOPIC OF DISCUSSION
THURSDAY, FEBRUARY 5, 1998
PLANS FOR THE NEXT SUPERVISORS MEETING
UPDATE ON PRE-APPROVAL OF STATE TRUST FUND
REIMBURSEMENTS
INFORMATION ON THE "LIKESE PROGRAM" AND ,rs
APPLICABILITY TO TANK INSPECTIONS
CONTINUE THE DISCUSSION OF REGIONAL ISSUES
. AND QUESTIONS
B·R·E"A*K
GROUNDWATER SECTION STAFF TRAINING NEEDS FOR 1998
THE NEED FOR DWQ OVERHAUL OF THE REVIEWICOMMENT
PROCESS FOR RCRA AND SUPERFUND PROJECTS
UPDATE ON THE ACTIVITIES OF THE DATABASE
WORK GROUP
L*U*N"C"H
CONTINUE THE DISCUSSION OF REGIONAL ISSUES
AND QUESTIONS
B"R*E"A"K
CONTINUE THE DISCUSSION OF REGIONAL ISSUES
AND QUESTIONS
ADJOURII FOR A SAFE TRIP HOME
Page 2 of 3
DISCUSSION
LEADER
Bush
Boshoff
Barnhardt/Brown
R.0. Supervisors
(in rotation)
Boshoff
Cheek
Boshciff
R.O. Supervisors
(in rotation)
R.O. Supervisors
(in rotation)
SMT2-98.XCL
GROUNDWATER SUPERVISORS' MEETING
FAYETTEVILLE REGION
SLEEP INN -HIGHWAY 53 & INTERSTATE 95
SOUTHWESTERN CONFERENCE ROOM
FEBRUARY 4 -5, 1998
LISTING OF REGIONAL OFFICE ISSUES
RRO: Jay Zimmerman
1. Establishment of Criteria to Ensure Consistency across
the State in Re-ranking Sites per 15A NCAC 2L .0115 .
2. Applicability of Risk Based Corrective Action to
Underground Storage Tank Closure.
MRO: Barbara Christian
1. Update on the Implementation of the Risk Based
Rules for Underground Storage Tanks .
FRO: Art Barnhardt
1. Risk Based Rules and Land Use Classifications.
2. Policy and Technical Issues Concerning Bedrock
Contamination.
3. Policy Concerning Maximum Rate for Minimum Work on
Pre-approved Activities.
4. Permitting, So ils Remediation, and the Risk Based
Rules.
WIRO: Charles Stehman
1. Update on Procedures Used by Contractors in
Tank Tightness Testing .
2. Home Heating Oil Tank Releases .
3. Staff Training in Basic Hydrogeology, Chemical Analysis, and
Innovative Technologies.
4. Request for a Report from the Attorney General's Office
on the Recent Pump Lockout in Smithfield and the
Legal Precedent Established for Other Non-Compliant
Situations.
WARO: Willie Hardison
1. Update on the Status of Soil Remediation Permits.
2. Update on the Status of the Site Priority Ranking Form .
3. Status of the Risk Based Notice of Regulatory Requirements
or NORRs.
4. Status of Soil and Groundwater Guidelines for
Non-Underground Storage Tank Releases
(i.e. Volume 1 Guidelines).
Page 3 of 3
Author: Bob Cheek at NRGWS0lP
Date: 1 /14/1998 5:48 PM
Priority: Normal
Receipt Requested
TO: David Hance
CC: Arthur Mouberry
CC: Ted Bush
Subject: Agenda Item for Feb. GW Supervisor meeting
------------------------------------Message Contents------------------------------------
Please add the following item for the meeting Agenda -15 minutes
should be sufficient time.
'Status of Draft Changes in the Well Construction Rules'
Author: Bob Cheek at NRGWS0lP
Date: 1/5/1998 5:59 PM
Priority: Normal
TO: David Hance
CC: Ted Bush
Subject: AGENDA ITEM FOR FEBRUARY GW SUPERVISOR MEETING
------------------------------------Message Contents------------------------------------
DWQ review & comment on RCRA & SUPERFUND Projects -(a) How to
streamline existing cumbersome review/comment process?; and (b) What
types of documents do ROs need/not need to review, comment on and get
copies of?
Author: Burrie Boshoff at NRGWS0lP
Date: 1/16/1998 6:01 PM
Priority: Normal
TO: David Hance
Subject: Re[2]: AGENDA ITEMS FOR THE FEBRUARY GW SUPERVISORS MTG.
------------------------------------Message Contents------------------------------------
David,
I have the following agenda items:
1. RBCA follow-up on training
Policy issues
Technical Questions
Additional Training
2 . STF Pre-approval
3. Training for 1998
4. Database Workgroup
THKS Burrie
Reply Separator
Arthur
Bill
Burrie
Burrie
Burrie
Burrie
Subject: RE: AGENDA ITEMS FOR THE FEBRUARY GW SUPERVISORS MTG .
Author: David Hance at NRGWSOlP
Date: 1/16/98 4:39 PM
30
45
15
15
15
15
*** MESSAGE/ GW SUPERVISORS MEETING FEBRUARY '98/ AGENDA ITEMS****
HELLO EVERYONE,
JlJST A REMINDER .... THE AGENDA ITEMS AND EXPLANATIONS OF THE ITEMS
ARE DUE TODAY FRIDAY, 1/16/98.
min
min
min
min
min
min
IF YOU HAVE NOT SENT AGENDA ITEMS OR IF YOU MISSED ANYTHING ON WHAT
YOU HAVE SENT TO ME PRIOR THIS E-MAIL MESSAGE ...... PLEASE DO SO.
HAVE A GOOD HOLIDAY WEEKEND,
DAVID HANCE
Author: "Art Barnhardt GW" <[e-mail]> at Internet
Date: 1/16/1998 5:22 PM
Priority: Normal
Receipt Requested
TO: David Hance at NRGWS0lP
Subject: RE: AGENDA ITEMS FOR THE FEBRUARY GW SUPERVISORS MTG.
------------------------------------Message Contents------------------------------------
Here they are David,
1-Additional discussion of the Risk Rules, specific to the Land
Use Classification.
2-Update from the "Bedrock Workgroup", if staff involved comes to
the meeting.
3-FRO Information Item: James Brown & Co. will present
the "LIKSE Program". LISKE is a search engine type program
that searches a set of our policy statements, regulatory
interpretations, internal memos and other various resource type
documents which are used by UST inspectors to guide their
activities .
4-Preapproval. Discussion of maximum rate for miminum work.
5-Risk Rule Guidelines: Great job done by the Staff: Needed
clarification of minor problems found. Example: Soil can be
returned to UST excavation with Permit. This type permit does
not exist, plus we don't want to issue any per DWQ current
Policy and Rule restrictions.
ArtB.---FRO
!AN 20 '98 10:05AM P .2
From:
Organization:
To:
"Stanley Jay Zimmerman" <[e-mail].n
DEHNR .. Raleigh Regional Office
[e-mail]. us
Date sent:
Subject:
Copies to:
Priority:
David,
Fri, 16 Jan 199811:37:51 EST
RROAgenda
DWQ Groundwater Section RRO staff
normal
I would like to submit the following as agenda items for discussion
during the next GW Supervisor's mtg. in FRO:
1. Establishment of criteria to ensure consistency between
regions when reranking sites per 2L .0115. ( i.e .- a site is
legitamately ranked as high but due to site specific info. we rerank
to low and close the site}.
2. Discuss the application of RBCA to UST closure reports
(no CSA submitted) when part or all of the TPH results are< action
levels yet file not closed. Do we require all sources to complete
11 expanded 11 analyses?
Thats all I have for now.
Thanks
Jay
Karen A. Harmon -1-Fri, 16 Jan 1998 17:11 :30
Author: "Charlie Stehman" <Charlie stehman@wiro .enr.state .nc.us> at Internet
Date: 1/21/1998 l:58 PM
Priority: Normal
Receipt Requested
TO: David Hance at NRGWS0lP
TO: [e-mail] .nc.us at Internet
TO: [e-mail] at Internet
TO: [e-mail] at Internet
TO: [e-mail] at Internet
TO: [e-mail] at Internet
TO: [e-mail] .us at Internet
Subject: Agenda Items
------------------------------------Message Contents------------------------------------
AGENDA ITEMS FROM THE WILMINGTON OFFICE:
1. Update on tank-tightness issues, with special reference to
certain testing companies and certain petroleum marketers.
2. Home heating oil tank releases: recently we have been
getting a lot of reports of leaking situations from petroleum vendors
and truck drivers. These individuals or companies have reported
their findings in order to avoid liability. Some releases are from
UST's but many are from AST's. Many releases are coming from lines
of gravity feed AST's systems.
3. Training: staff have requested more training in areas of
basic hydrogeology, chemical analysis and innovative technology .
4. Wilmington would like a report from the AG's office and the
RRO on the recent pump lockout in Smithfield and precedent which this
may establish for other non-compliant situations in other regions .
Elfl[C GROUNDWATER COMf!IITTZgE A,GENDA ITEM# 2
AGENDA ITEM:
EXPLANATION:
Hearing Officer's Re port and Re quest for Variance for a Unocal Co rp oration site
in the Derita Community of Charlotte, North Carolina (Groundwater Incident
Number 3751).
The Unocal Corporation operated a retail gasoline station at this site at 2932
Gibbon Road in Charlotte, North Carolina until 1987. During that year this property was
sold to Mr. frank Dwyer of Charlotte, North Carolina. As a condition of the sale of this
property tank tightness testing was performed in 1987 on seven existing underground
storage tanks at the site. All tanks were subsequently removed from this property by the
Unocal Corporation and a closure report filed with the Mooresville Regional Office in
October 1991. One 4,000 gallon underground storage tank failed tank tightness testing.
A preliminary site assessment submitted on January 14, 1988 confirmed that a release
had occurred from this tank. Since tank removal by the Unocal Corporation, Mr. Frank
Dwyer has used 2932 Gibbon Road as an auto repair shop (Dwyer's Auto Repair). The
Unocal Corporation is entirely responsible for cleanup of this release which is shown in
Division of Water Quality files as Groundwater Incident Number 3751. This variance
is being requested for all the property at 2932 Gibbon Road. This property is located in
an area with a mixture of residential, industrial, and commercial development.
The June 2, 1992 comprehensive site assessment revealed groundwater plume
mostly within the property boundaries approximately 52,000 square feet in size. Site
assessment information on file in the Mooresville Regional Office shows that the vertical
extent of this plume to be approximately 90. 78 feet below the ground surface. Dissolved
gasoline products have been defined vertically in the bedrock at this site. This release
occurred in unconsolidated materials above the bedrock.
On March 25, 1993 a corrective action plan submitted by the Unocal
Corporation was approved by the Division of Water Quality. The cleanup technologies
implemented by the company at this site on July 16, 1993 were air sparging and soil
vapor extraction (SVE). Air sparing relies on the introduction of air to separate volatile
substances from subsurface materials. Soil vapor extraction uses suction to remove
contaminants from soils. Use of soil vapor extraction is intended to reduce contaminant
levels in soils without requiring the removal and treatment of soils offsite and the
introduction of new or treated fill materials. These technologies were implemented as
a means of cleaning up soils, to prevent_ the migration of contaminants in soils into
groundwater, and to inhibit the further degradation of groundwater at this site. The soil
vapor extraction system was activated on July 16, 1993 and operated until September 22,
1994. The air sparging system operated from August 17, 1993 until March 20, 1996.
Since discovery of the release on January 14, 1988 the Unocal Corporation has
disposed of a total of 2,300 tons of petroleum contaminated soil during tank closure.
The Unocal Corporation has submitted information showing that the total mass of
vaporous hydrocarbons recovered by the SVE system is estimated at3,400 pounds which
is equivalent to 567 gallons of gasoline.. The company reports that a total of$ 751,863
has been expended to remove tanks, conduct site assessments, and cleanup soils this site.
All these costs associated with Groundwater Incident# 3751 have been incurred by the
Unocal Corporation. It has been estimated that continued operation of air sparging with
soil vapor extraction at this site will cost approximately$ 20,000 per year. The Unocal
-i-
EMC GROUNDWATER COMMITTEE "AGENDA ITEMtfl~
Corporation does not believe that there are alternate technologies that will remediate the
site any more effectively than those used over the past few years.
From the time cleanup was implemented June 16, 1993 through March 1, 1995,
concentrations of substances were significantly reduced by groundwater cleanup
technologies located at the site. Since August 1995 analysis of samples from monitoring
wells showed only marginal reductions in the concentration of substances in
groundwater. Analysis of groundwater samples taken on December 1, 1995 and on
February 25, 1996 showed there was no significant increase or decrease in
concentrations of Benzene and other substances at the off-site monitoring wells, while
cleanup operations were being conducted. Based on groundwater analysis of samples
from semi-annual monitoring from 1992 through 1995, the Division of Water Quality
recommended that air sparging and soil vapor extraction technologies be turned off to
determine if residual contaminants in the soils and subsurface would recontaminate the
groundwater, if no treatment system were operating. Upward "rebounding" of
concentrations above the Groundwater Quality Standards in 15A NCAC 2L .0202 has
been noted for some of these monitoring wells. However, with the exception of two on-
site monitoring wells, the groundwater analysis on July 29, 1996 has shown that
concentrations of substances in monitoring wells have been reduced below detectable
limits. Substances in the two on-site wells near the area where the release occurred
remain slightly above the Groundwater Quality Standards in 15A NCAC 2L .0202.
The Unocal Corporation believes that a variance at this site will not endanger
public health, safety or the environment. There are forty-two (42) water supply wells
serving residences and businesses within½ mile of the site. Most of these properties are
served by public water from the City of Charlotte. Of the five wells located nearest to
the site, four of them are not being used for drinking water supply. The well nearest to
2932 Gibbon Road, that is currently used for water supply, is located at 6810 Nevin Road
and is identified in the variance request as "B&B Leather". The well has been
continually sampled since April 1993 and substances have never been reported in this
well. The Unocal Corporation asserts that remaining substances in the contaminant
plume exceeding the 15A NCAC 2L .0202 Groundwater Quality Standards, such as
Benzene, would not reach the closest receptor, B&B Leather Company, for 22 years.
This estimated range assumes no dilution or attenuation of the plume occurs. The
company has submitted information showing that conditions at the site are such that
substances in the groundwater will likely biodegrade due to the presence of indigenous
microorganisms in the subsurface. The company asserts that these natural conditions are
such that the entire plume of substances is expected to degrade to the extent that
concentrations will be below the Groundwater Quality Standards in 15A NCAC 2L. 0202
before the plume reaches this cross-gradient water well. The company has submitted
information showing that no water supply intakes or water supply lines will be impacted
if a variance is granted at this site. The nearest surface water body, Erwin Creek, is
approximately 1,100 feet away and has not been impacted by substances at this site.
On September 23, 1996 the Mooresville Regional Office recommended that this
variance be granted. On February 7, 1997 the Division of Epidemiology concurred with
the recommendation of the regional office. On September 5, 1997 the Director of the
Division of Water Quality gave approval for this variance to proceed to public notice and
hearing pursuant to the requirements contained in 15A NCAC 2L .0113.
Pursuant to 15A NCAC 2L .0113(d) and (e), public notice of this variance was
sentto adjacent property owners, forty-two well owners, the Mecklenburg County Health
Director, the City Manager for the City of Charlotte, and the Mayor of Charlotte on
October 16, 1997. Notice of this hearing was also published in the October 18, 1997
-ii-
EMC GROfl_NDWATER CO/VfM/fT..EE AGE~pA ITEM# 2
edition of the Charlotte Observer to meet requirements of15ANCAC 2L .0113(e)(l)(A).
In addition, approximately 158 notices of this variance request were sent to persons listed
in the "Groundwater Variance and Regulatory Actions Mailing List" to meet the
requirements of 15A NCAC 2L .0113(e)(l)(F).
A public hearing was held on November 18, 1997 in Charlotte, North Carolina.
This hearing was attended by one individual from S & ME Incorporated, representing
the Unocal Corporation. No other persons attended this hearing and no comments were
made at the hearing. Only one written comment was received prior to December 19,
1997 from -the Assistant Regional Engineer in the Public Water Supply Section
expressing no objection to granting this variance.
RECOMMENDATION:
It is recommended that the Environmental Management Commission
Groundwater Committee send the request for variance for the Unocal Corporation
site at 2932 Gibbon Road in Charlotte, North Carolina (Groundwater Incident
Number# 3751) to the Environmental Management Commission on March 12,
1998 with a request that this variance be granted pursuant to the requirements of
15ANCAC 2L .0113 and North Carolina General Statute 143-215.3(e). It is also
recommended that this variance be approved without the requirement for the
Unocal Corporation to conduct monitoring based on information in the variance
request demonstrating the effectiveness of remediation efforts, the cost incurred
by the company, the results of monitoring showing no significant increase in
substances at this site when cleanup operations were suspended, the comment
received and interest level from the public who were provided advanced notice of
the public hearing, and the lack of impact the site has on water supply wells.
-iii-
PUBLIC HEARING
A public notice was published advising interested parties that a public hearing was
scheduled on November 18, 1997 (Attachment I). In addition to publishing the notice, a copy of
the notice was sent to 200 people, including 42 well owners within one half mile of the site. The
public hearing was conducted as scheduled and the Division was represented by the following
staff members:
Tommy Stevens
Allen Schiff
David Hance
Hearing Officer
Mooresville Regional Office
Central Office Groundwater Section
The hearing was attended by one person representing Unocal Corporation, who was their
consultant from S & ME,Inc. No one present requested to make verbal comments. Opening
remarks were given by the hearing officer, followed by the staff presentation by Allen Schiff
(Attachment II). No written comments were received during the hearing. One written comment
was received on November 20, 1997 from Britt Setzer, Assistant Regional Engineer, Public Water
Supply Section. His comment was that there was no objection to the variance being granted since
city water is available in that area (Attachment ID).
DISCUSSION
Attachment IV consists of the variance request submitted by S & ME,Inc. to the Division
ofWater Quality dated June 13, 1996. As a part of the public notice, attachment I also includes a
summary of the variance application and issues to be considered at the hearing. The following is a
brief summary of the history of this site and facts relating to the variance request.
* A release was discovered from this site in 1987 which involved the failure of the tank tightness
for one of seven US T's at the site. Soil and groundwater contamination was removed upon
discovery. .,.
* On April 19, 1988 a Notice ofNoncompliance was issued based on ISA NCAC 2L requiring
Unocal to assess the contamination impact and propose corrective action.
* On June 2, 1992 the CSA was submitted which revealed that a groundwater plume existed
mostly within the property and was approximately 52,000 square feet in size,
' .
* The CAP was submitted on December 28, 1992 which called for· air sparging and soil vapor
extraction. There was a public notice published in the Charlotte Observer on Febrmµy 15, 1993
and the CAP was approved on March 25, 1993.
* The soil vapor extraction system was activated on July 16, 1993 and operated until September
22, 1994. The air sparging system ran from August 17, 1993 until March 20, 1996.
Page2
* Groundwater flow direction from the site has been determined to be southwest.
* The nearest well to the site is located at the B&B Leather Company, which is approximately
150 feet east-northeast of the property. The well has been continuously sampled since April 1993
and has never shown any contamination. One well located at Gamble Pallet Company which is
375 feet west of the site has shown low levels of Tetrachlorethane, however, this finding is
unrelated to the Unocal site.
* There are a total of 42 active and inactive wells located within½ mile of the site. Most all of
these properties are served by city water.
* The nearest surface water body is an unnamed tributary to Erwin Creek, which is 1, 100 feet
from the site and has not been impacted from this incident
RECOMMENDATION
Based upon Unocal's request for variance, input from the public hearing and staff
recommendation from the Mooresville Regional Office, it is the hearing officer's recommendation
that the variance be granted with no future groundwater monitoring at the site. The following
facts were considered in arriving at this recommendation:
( 1) Review of the variance request and supporting documentation
(2) Remediation system has extracted approximately 3400 pounds of petroleum hydrocarbons
from the soil and groundwater
(3) Unocal has expended$ 796,532.00 as ofNovember 1997, none of which is reimbursable from
state trust fund
(4) There has been no increase in groundwater contaminants when the system is turned off
( 5) There were no· comments received either at the hearing or in writing following the hearing
that expressed any concern over the granting of this variance
(6) Written comment from the Public Water Supply Section indicates no objection to the variance
(7) Additional remediation at this site is not economically reasonable or practical and would not
likely result in any further improve in groundwater quality
(8) At the movement of groundwater in this area at a rate of approximately 12 feet/year, it is not
projected that the contaminate plume would not reach the closest source ( well at B&B
Leather) for 22 years. Through natural degradation it is projected that by the time the plume
were to reach the closest well (B&B Leather) contaminants would not exceed 15A NCAC
2L . 0202 Groundwater Quality Standards.
ATTACHMENT-I
PUBLIC NOTICE AND SUMMARY OF THE
VARIANCE FOR GROUNDWATER INCIDENT
NUMBER3751
NOTICE OF VARJANCE APPLICATION AND HEARING
DEPARTMENT OF ENVIRONMENT, HEALTH AND NATURAL
RESOURCES
DMSION OF WATER QUALITY
Notice is hereby given of a variance application and public hearing to be held by the Department of
Environment and Natural Resources on behalf of the Environmental Management Commission. The hearing
concerns a request f9r a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202 an_d the
Corrective Action requirements of 15A NCAC 2L .0106 (j) for a site at 2932 Gibbon Road in Charlotte, North
Carolina. The Division of Water Quality refers to this site identified in the variance request as Groundwater
Incident# 3751. This property, previously owned by the Unocal Corporation of Atlanta, Georgia, was
operated as a retail gasoline outlet until 1987. The property is now owned by Mr. Frank Dwyer of Charlotte,
North Carolina. The Unocal Corporation is entirely responsible for cleanup for Groundwater Incident# 3 751.
This variance application from the Unocal Corporation was received for review by the Department on June
13, 1996.
The property where the release of petroleum product has occurred is located as follows: Inside the city
limits of Charlotte, North Carolina in the Derita Community. Take Interstate 85 in Charlotte and exit onto
Sugar Creek Road. Travel north on Sugar Creek Road two miles and turn left onto Nevin Road. Travel on
Nevin Road 1/4 of a mile until Gibbon Road crosses Nevin Road. This site consists of 0.87 acres of land at
2932 Gibbon Road. The site is listed in Mecklenburg County tax records as Parcel Number 045-135-02.
The Unocal Corporation requests that the Environmental Management Commission grant the
following variance to its rules under the authority of 15A NCAC 2L .0113 so that it does the following:
(1) Allow concentrations of Benzene, Ethylbenzene, Toluene, Xylene (-o,-m, and p), Methyl Tert-
Butyl Ether (MTBE), Naphthalene, Isopropyl Ether, Ethylene Dibromide, 1,2-Dichloroethane, bis(2-
ethlylhexyl)phthalate {DEHP}, Chloroform, Methylene Chloride, 1-Methyl-Naphthalene, 2-Methyl-
N aphthalene, T~trachloroethylene, Methylene Chloride, and Phenol to remain at levels above 15A
NCAC 2L .0402 Groundwater Quality Standards as analyzed on July 29, 1996 in all monitoring wells
except for concentrations of substances found by analysis using US Environmental Protection Agency
Method 625 in Monitoring Well # 12. Bis(2-ethylhexyl)pbthalate {also known as Di(2-
ethylhexyl)phthalate (DEHP)} found by the US Environmental Protection Agency Method 625 in
Monitoring Well# 12 will remain at the concentrations level as analyzed on October 28, 1996. These
concentrations will be required to remain within the property boundaries of 2932 Gibbon Road.
As a condition of the sale of this property in 1987 to Mr. Frank.Dwyer, ta.IJk tightness testing was
performed in 1987 on seven existing underground storage tanks at the site. All tanks were
subsequently removed from this property by the Unocal Corporation and a closure report filed with
the Mooresville Regional Office in October 1991. OneA,000 gallon underground storage tank failed
tank tightness testing. A preliminary site assessment submitted on January 14, 1988 confirmed that
a release had occurred from this tank. Since tank removal by the Unocal Corporation, Mr. Frank
Dwyer has used 2932 Gibbon Road as an auto.repair shop (Dwyer's Auto Repair). This property is
located in an area with a mixture of commercial, industrial, and residential development.
1
(2)
The comprehensive site assessment was completed on June 2, 1992 and corrective action plan
for this site was submitted on December 23, 1992. The comprehensive site assessment revealed a
plume of BTEX and dissolved hydrocarbons contaminating subsurface soil and groundwater. Site
assessment information on file in the Mooresville Regional Office shows that the vertical extent of
this plume to be approximately 90.78 feet below the ground surface. Dissolved gasoline products have
been defined vertically in the bedrock at this site. This plume was estimated to have covered an area
of approximately 167,199 square feet (3.84 acres) prior to the implementation of corrective actions
by the Unocal Company.
From June 16, 1993 through August 21, 1995, concentrations of substances at this site were
significantly reduced by groundwater cleanup technologies located at the site. Since August 1995
analysis of samples from monitoring wells showed only marginal reductions in the concentration of
substances in groundwater. Analysis of groundwater samples taken on December 1, 1995 and on
February 25, 1996 showed there was no significant increase or decrease in concentrations of Benzene
and other substances at the off-site monitoring wells, while cleanup operations were being conducted.
Based on groundwater analysis of samples from semi-annual monitoring from 1992 through
1995, the Division of Water Quality recommended that air sparging and soil vapor extraction
technologies be turned off to determine if residual contaminants in the soils and subsurface would
recontaminate the groundwater, if no treatment system were operating. Since the cleanup system was
turned off on March 20, 1996, upward "rebounding" of concentrations above the Groundwater Quality
Standards in 15A NCAC 21 .0202 has been noted for some of these monitoring wells. With the
exception of two on-site monitoring wells, the groundwater analysis on July 29, 1996 has shown that
concentrations of substances in monitoring wells have been reduced below detectable limits.
Substances in the two on-site wells near the area where the release occurred remain slightly above the
Groundwater Quality Standards in 15A NCAC 21 .0202.
Based on concentrations of substances found in wells used for recovery or monitoring
contaminants and calculations of the time it would take for substances to migrate to receptors at
surrounding properties, the company does not believe that a variance will result in an adverse impact
to the public. There are no drinking water supply intakes at surface water bodies within½ mile of the
site. Public water supply lines are deemed too shallow to be impacted by substances at 2932 Gibbon
Road.
,.
Allow'for the restoration of groundwater without requiring remedial actions in accordance with
15A NCAC 2L .0106G). The Unocal Corporation has submitted supporting information
demonstrating that the continued application of best available technology will not result in significant
long term remediation of the site to the Groundwater Quality Standards contained in 15A NCAC 21
.0202. This is due to the high probability that continued remediation activities at the site will not
significantly reduce contaminant levels below Groundwater Quality Standards in 15A NCAC 21
.0202. Since discovery of the release on January 14, 1988 the Unocal Corporation has disposed of
a total of2,300 tons of petroleum contaminated soil during tank closure.. The Unocal Corporation
has submitted information showing that the total mass of vaporous hydrocarbons recovered by the
SVE system is estimated at 3,400 pounds which is equivalent to 567 gallons of gasoline .. The
company reports that a total of $ 751,863 has been expended to remove tanks, conduct site
assessments, and cleanup soils this site. The Unocal Corporation does not believe that the public will
benefit from continued cleanup using present technology atthe site or alternatives discussed and that
a variance is the most effective means of dealing with remaining concentrations.
2
The hearing will be held pursuant to the requirements oftitle15A NCAC 21 .0113 as follows:
CHARLOTTE
Tuesday, November 18, 1997
7:00P.M.
Mecklenburg County Courthouse -Criminal Courts Building
2ND Floor -Courtroom Number 2201
700 East Fourth Street
Oral Comments may be made during the hearing, or written statements may be submitted to the
agency by December 19, 1997. Written copies of oral statements exceeding three minutes are requested.
Oral statements may be limited at the discretion of the hearing officer.
Please forward comments or information requests to:
David Hance
EHNR-DWQ-Groundwater Section
P.O. Box 29578
Raleigh, NC 27626-0578
Phone: [phone]; Fax: [phone]
Internet E-Mail Address: [e-mail]
This proposed variance request is available for public inspection at the locations listed below. Copies
may be obtained at each location for a charge of ten cents per page. A summary of information including a
discussion of site cleanup, a detailed discussion of recent and historic on-site and off-site groundwater
monitoring, monitoring of wells to determine the effectiveness of the cleanup systems used at this site, a
discussion of sampling and analysis of inactive and active drinking water supply wells, and cost evaluations
of alternative best available technologies will be made available upon request. Please contact Mr. Hance or
the Mooresville Regional Office for this information. 1
Dept. of Environment and Natural Resources
Division of Water Quality
P.O. Box 29578
2728 Capital Blvd.
Raleigh, NC 27626-0578
[phone]
~J_vv
A. Preston Ho;d, ~
Director, Division of Water Quality
Dept. of Environment and Natural Resources
Division of Water Quality
Mooresville Regional Office
919 North Main Street
Mooresville, NC 28115
[phone]
3
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SUMMARY OF VARIANCE APPLICATION AND HEARING
DEPARTMENT OF ENVIRONMENT, HEALTH AND NATURAL
RESOURCES
The property where the release o! petroleum product has occurred is located as follows: This
property, previously owned by the Unocal Corporation of Atlanta, Georgia, was operated as a retail
gasoline outlet until 1987. The property is now owned by Mr. Frank Dwyer of Charlotte, North Carolina.
The Unocal Corporation is entirely responsible for cleanup for Groundwater Incident # 3751. This
variance application from the Unocal Corporation was received for review by the Department on June
13, 1996. Inside the city limits of Charlotte, North Carolina in the Derita Community. Take Interstate
85 in Charlotte and exit onto Sugar Creek Road. Travel north on Sugar Creek Road two miles and turn
left onto Nevin Road. Travel on Nevin Road 1/4 of a mile until Gibbon Road crosses Nevin Road. This
site consists of 0.87 acres of land at 2932 Gibbon Road. The site is listed in Mecklenburg County tax
records as Parcel Number 045-135-02. The Division of Water Quality refers to this site identified in the
variance request as Groundwater Incident# 3751.
The Unocal Corporation requests that the Environmental Management Commission grant the
following variance to its rules under the authority of 15A NCAC 2L .0113 so that it does the following:
(1) Allow concentrations of Benzene, Ethylbenzene, Toluene, Xylene (-o,-m, and p), Methyl
Tert-Butyl Ether (MTBE), Naphthalene, lsopropyl Ether, Ethylene Dibromide, 1,2-Dichloroethane,
bis(2-ethlylhexyl)phthalate {DEHP}, Chloroform, Methylene Chloride, 1-Methyl-Naphthalene,
2-Methyl-Naphthalene, Tetrachloroethylene, Methylene Chloride, and Phenol to remain at levels
above 15A NCAC 2L .0202 Groundwater Quality Standards as analyzed on July 29, 1996 in all
monitoring wells except for concentrations of substances found by analysis using US
Environmental Protection Agency Method 625 in Monitoring Well # 12. Bis(2-
ethylhexyl)phtl;,alate {also known as Di(2-ethylhexyl)phthalate (DEHP)} found by the US
Environmental Protection Agency Method 625 in Monitoring Well # 12 will remain at the
concentrations level as analyzed on October 28, 1996. These concentrations will be required
to remain within the property boundaries of 2932 Gibbon Road.
As a condition of the sale of this property in 1987 to Mr. Frank Dwyer, tank tightness
testing was performed in 1987 on seven existing underground storage tanks at the site. All
tanks were subsequently removed from this property by the Unocal Corporation and a closure
report filed with the Mooresville Regional Office in October 1991. One 4,000 gallon
underground storage tank failed tank tightness testing. A preliminary site assessment submitted
on January 14, 1988 confirmed that a release had occurred from this tank. Since tank removal
by the Unocal Corporation, Mr. Frank Dwyer has used 2932 Gibbon Road as an auto repair shop
(Dwyer's Auto Repair). This property is located in an area with a mixture of commercial,
industrial, and residential development.
The comprehensive site assessment was completed on June 2, 1992 and corrective action
plan for this site was submitted on December 23, 1992. The comprehensive site assessment
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revealed a plume BTEX and dissolved hydrocarbons contaminating subsurface soil and
groundwater. This area was located near the northeast property line approximately 40 feet east-
northeast of the area where the·unocal Corporation retail outlet had it's gasoline pump islands.
Site assessment information on file in the Mooresville Regional Office shows that the vertica-I
extent of this plume to be approximately 90. 78 feet below the ground surface. Dissolved
gasoline products have been defined vertically in the bedrock at t~is site. This release occurred
in unconsolidated materials above the bedrock. This plume was estimated to have covered an
area of approximately 167,:1.99 square feet (3.84 acres) prior to the implementation of
corrective actions by the Unocal Company. It was estimated that the plume of substances once
extended onto 1,600 square feet of an adjacent property owned by the Durane Gas Company
(Mecklenburg County Parcel Number 045-143-94). The remainder of this plume was found to
cover most of the former Unocal Corporation site at 2932 Gibbon Road. No other adjacent
property are known to have been impacted by this release identified as Groundwater Incident
Number 3751.
The Unocal Corporation implemented cleanup of this site on July 16, 1993. During tank
removal 2,300 tons of gasoline contaminated soil was extracted, treated with passive
bioremediation on-site, and later transported off-site for treatment. The company believes that
the majority of gasoline contaminated soils were removed from this site and thus the
predominant source of contaminants that would have likely had an impact on groundwater. The
cleanup system used by the Unocal Corporation consisted of a combination of air sparging and
soil vapor extraction. Soil vapor extraction and air sparging were used to reduce the
concentrations of petroleum hydrocarbons in soils at this site from June 16, 1993 through
March 20, 1996. Air sparing relies on the introduction of air to separate volatile substances
from subsurface materials. Soil vapor extraction uses suction to remove contaminants from
soils. Use of soil vapor extraction is intended to reduce contaminant levels in soils without
requiring the removal and treatment of soils offsite and the introduction of new or treated fill
materials. These technologies were implemented as a means of cleaning up soils, to prevent
the migration of contaminants in soils into groundwater, and to inhibit the further degradation
of groundwater at this site.
The Divisipn of Water Quality required the Unocal Corporation to perform groundwater
monitoring to determine the vertical and lateral extent of contamination. Beginning on March
4, 1992 the company conducted comprehensive groundwater sampling at eleven monitoring
wells. The highest concentration of Benzene found in a monitoring well, prior to implementation
of groundwater cleanup, was 5.50 milligrams per liter found in Monitoring Well # 10 during the
March 4, 1993 sampling event. The Groundwater Quality Standard for Benzene in 15A NCAC
2L .0202 is 0.0001 milligrams per liter. The highest concentration of Methyl-Tert Butyl Ether
at this site above Groundwater Quality Standards was also found in Monitoring Well # 10 on
March 4, 1993 at 6.3 milligrams per liter. The Groundwater Quality Standard for MTBE is 0.200
milligrams per Liter (mg.IL). MonitoringWell # 10 is located within the area of the property that
the Unocal Corporation had underground storage tanks. Concentrations of Ethylbenzene,
Toluene, Xylene, Ethylene Dibromide, lsopropyl Ether, Chloroform, Methylene Chloride, 1-
Methyl-Naphthalene, 2-Methyl-Naphthalene, Tetrachloroethylene, Phenol, and Bis(2-
ethylhexyl)phthalate {also known as Di(2-ethylhexyl)phthalate (DEHP)} have appeared
periodically in three of six on-site monitoring wells at levels significantly above the Groundwater
2
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Quality Standards in Title 15A NCAC 2L .0202. All monitoring wells at this site have at one time
or another shown concentrations of substances above the Groundwater Quality Standards from
March 4, 1992 through July 29, 1996. The Unocal Corporation constructed Monitoring Well #
6 (Mecklenburg County Parcel Number 045-134-07) located on off-site property at the Handy
Pantry at 2947 Gibbon Road. Analysis of this downgraident monitoring well began on March 4,
1993. · Ten different sampling events have occurred at this property. Except for Bis(2-
ethylhexyl)phthalate {also known as Di(2-ethlyhexyl)phthalate (DEHP)}, no substances have
ever appeared in this well abgve Groundwater Quality Standards. The highest concentration of
DEHP appeared in this well at a concentration of 6.43 x 10·3 milligrams per liter (mgtL). The
Groundwater Quality Standard for DEHP 3.00 x 10·3 milligrams per liter (mg'L). This substance
has not appeared in the off-site well since December 1995. Analysis of the upgraident
monitoring well at the Durane Gas Company (Monitoring Well # 15) began on May 21, 1992.
Eight different sampling events occurred at this well. From May 21, 1992 through February 25,
1996 groundwater monitoring has been conducted by the Unocal Corporation at the off-site
Monitoring Well# 15 (Durane Gas Company). Substances that have appeared in this well have
not exceeded Groundwater Quality Standards in 15A NCAC 2L .0202. Sampling of this well
could not be performed on July 29, 1996 due to the discovery by the Unocal Corporation that
this well has been removed. It is believed that the owner of the Durane Gas Company property
at 3008 Gibbon Road (Mecklenburg County Parcel Number# 043-026-29) removed this well.
Except for Monitoring Well # 12, the last sampling and analysis of all remaining monitoring
wells occurred on July 29, 1996. The most significant substance found in Monitoring Well # 12
was Bis(2-ethylhexyl)phthalate {also known as Di(2-ethylhexyl)phthalate (DEHP)}. The August
18, 1995 groundwater monitoring event showed DEHP at a concentration of 2. 70 milligrams
per liter (mg'L). The Groundwater Quality Standard for DEHP is 3.00 x 10·3 milligrams per liter
(mg'L).
Semi-annual monitoring of this well from August 18, 1995 through July 29, 1996 showed that
concentrations of DEHP remained significantly above the Groundwater Quality Standards. DEHP
is not a constituent of or an additive to petroleum. The presence of this substance in
groundwater at this site could be attributed to sources of groundwater contamination other than
Groundwater Incident Number 3751. However, it is believed that DEHP could have gotten into
this well inadvertently as a result of cleanup operations. Information in the Mooresville Regional
Office showed that the consulting firm that the Unocal Corporation had hired to conduct
maintenance on the air sparging system had not properly maintained coalescing filters for this
equipment. It must be noted that Bis(2-ethylhexyl)phthalate {also known as Di(2-
ethlyhexyl)phthalate (DEHP)} is a lubricating fluid used in vacuum pumps for air sparging. Since
the coalescing filters were not properly maintained on the air sparging equipment, it is possible
that this fluid could have migrated out of the pumping system and into Monitoring Well # 12.
In response to Groundwater Section staff concerns about persistently elevated DEHP
concentrations in this well, the Unocal Corporation conducted additional cleanup of this site.
On October 18, 1996 the company pumped an additional 300 gallons of water out of
Monitoring Well # 12. Special groundwater sampling of Monitoring Well # 12 on October 28,
1996 revealed that the concentration of Di (2-ethlyhexyl) phthalate (DEH P) was below detectable
limits. No other substances appeared in the groundwater sample from Monitoring Well # 12
3
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using USEPA Method 625. It must be noted that Monitoring Well# 12 is the deepest well at
this site at 90. 78 feet below land surface and is located the northeast corner of the former tank
pit area when the Unocal Corporation owned this property.
The Division also required Unocal Corporation to evaluate the effectiveness of groundwater
cleanup efforts by examining concentrations of substances in recovery wells beginning April 12,
1993. Recovery wells at the 2932 Gibbon Road site are used as s~mps to collect groundwater,
free product, and dissolved hydrocarbons from the site for treatment. Pumps convey this fluid
to the treatment system. Sarnples were obtained from four recovery wells located beneath the
parking lot and the area that formerly had the Unocal Corporation service station and pump
islands. Analysis of samples from recovery wells was also conducted by the Unocal Corporation.
A minimum of two sampling events and a maximum of sixteen sampling events have occurred
at the four recovery wells since April 1993. On July 29, 1996 Recovery Well # 2 and Recovery
Well # 4 had concentrations of substances below detectible limits. The Unocal Corporation
reported that it was not feasible to sample Recovery Well # 1 and Recovery Well # 3 due to the
proximity of these wells to Monitoring Well # 9 and Monitoring Well # 2 and effect that
sampling of the recovery wells might have had on the results from the monitoring wells.
Significant reductions in concentrations of substances have been observed in groundwater
samples taken from the recovery wells since the implementation of cleanup at this
site. Results from 1993 through 1996 has demonstrated reductions in the concentrations of
substances since the implementation of cleanup at this site.
From June 16, 1993 through August 21, 1995, concentrations of substances at this site
were significantly reduced by groundwater cleanup technologies located at the site. Since
August 1995 analysis of samples from monitoring wells showed only marginal reductions in the
concentration of substances in groundwater. Analysis of groundwater samples taken on
December 1, 1995 and on February 25, 1996 showed there was no significant increase or
decrease in concentrations of Benzene and other substances at the off-site monitoring wells,
while cleanup operations were being conducted.
Based on groundwater analysis of samples from semi-annual monitoring from 1992 through
1995, the Division of Water Quality recommended that air sparging and soil vapor extraction
technologies qe turned off to determine if residual contaminants in the soils and subsurface
would recontaminate the groundwater, if no treatment system were operating. Since the
cleanup system was turned off on March 20, 1996, upward "rebounding" of concentrations
above the Groundwater Quality Standards in 15A NCAC 2L .0202 has been noted for some of
these monitoring wells. With the exception of two on-site monitoring wells, the groundwater
analysis on July 29, 1996 has shown that concentrations of substances in monitoring wells
have been reduced below detectable limits. With respect to on-site monitoring wells,
Monitoring Well # 12 and Monitoring Well # 13 had concentrations of substances in
exceedence of the Groundwater Quality Standards in 15A NCAC 2L .0202. The analysis of
samples from the remaining on-site monitoring wells showed concentrations below detectable
limits. During the July 29, 1996 semi-annual groundwater monitoring event Benzene appeared
in Monitoring Well # 12 at a concentration of 3.34 x 10·3 milligrams per liter. The Groundwater
Quality Standard for Benzene is 1 x 10-3 milligrams per Liter. 1,2-Dichloroethane was also
found in this well at 2.48 x 10·2 milligrams per liter. The Groundwater Quality Standard for 1,2-
Dichloroethane is 3.8 x 10-4 milligrams per Liter. Concentrations of Benzene and other
4
10/7/97 version
substances in the recovery wells were below detectable limits in all four recovery wells on July
29, 1996. No significant reductions in concentrations have been observed since November 3,
1994. Substances at concentrations above the 15A NCAC 2L .0202 Groundwater Quality
Standards have not been observed in the off-site Monitoring Well # 6 (Handy Pantry) or
Monitoring Well # 15 (Durane Gas Company) since December 1995.
The Unocal Corporation has submitted supporting information showing that the variance will
not endanger public health; safety, or the environment. The company does not believe that
substances at 2932 Gibbon_Road have impacted adjacent water supply wells. A number of
water wells are known to exist within ½ miles of 2932 Gibbon Road. There are approximately
42 residential and businesses properties that obtain drinking water from water supply wells.
Six of these wells are known to be inactive and property owners are obtaining water supply from
the City of Charlotte. All remaining properties in the area obtain water supply from the City of
Charlotte.
The nearest of these wells to 2932 Gibbon Road are four "inactive" water supply wells and
one water supply well in-use on adjacent properties near this site that are potential receptors
under 15A NCAC 2L .0102(19). The water supply well reported to be in use was at the B & B
Leather Company at 6810 Nevin Road (Mecklenburg County Parcel Number 045-135-01).
The Unocal Corporation reports that water supply well at Delta Unit Rebuilders (Mecklenburg
County Parcel Number 045-372-20) was disconnected as early as March 11, 1994 and has
been replaced by city water. Another water supply well once existed at 2932 Gibbon Road when
the property was owned by the Unocal Corporation. On November 17, 1992 this well was
closed pursuant to 15A NCAC 2C .0100 with grout cement. From April 7, 1993 through July
29, 1996 sampling was conducted at the four inactive wells and the B & B Leather Company
Well to determine the impact the remaining substances from 2932 Gibbon Road may have on
these receptors. Except for the Gamble Pallet Company Well at 3020 Gibbon Road
(Mecklenburg County Parcel Number 043-026-28) concentrations of substances in area
drinking water wells were found below detectable limits since sampling began on March 7,
1993. The only substance ever found in the Gamble Pallet Company Well was
Tetrachloroethene (also known as Tetrachloroethylene or Perchloroethylene). The highest
concentration"'of this substance was 7.51 x 10·3 milligrams per liter on February 25, 1996.
The Groundwater Quality Standard for Tetrachloroethene is 7.0 x 10·4 milligrams per liter. The
semi-annual monitoring event on July 29, 1996 showed that the concentration of this
substance at 2.86 x 10·3 milligrams per liter. Prior to these monitoring events
Tetrachloroethene was never identified in this inactive drinking water well.
The Unocal Corporation reports that this inactive drinking water well is located
approximately 425 feet northwest of the site. Information in the variance request shows this
well located cross gradient from the direction of groundwater flow through the former Unocal
site at 2932 Gibbon Road. The Unocal Corporation does not believe that the Tetrachloroethene
found in this well is related to the release of petroleum under Groundwater Incident# 3751.
The Unocal Corporation has submitted calculations and other information demonstrating
that substances at this site are not likely to impact wells on adjacent properties and other
receptors to the extent that concentrations of substances on these properties will exceed
Groundwater Quality Standards in 15A NCAC 2L .0202. The company has calculated the time
periods it would take for various contaminants that have been found at this site to impact the
5
10/7/97 version
down-gradient receptors. These receptors include active and inactive water supply wells and an
unnamed creek. The concentration of contaminants in groundwater is primarily influenced by
the direction and rate of groundwater flow. The estimated groundwater flow rate is contained
in the site assessment and corrective action plan submitted by the Unocal Corporation to the
Mooresville Regional Office. Based on this information in the variance request, the Unocal Oil
Company asserts that groundwater in the area flows from 2932 Gibbon Road travels toward an
unnamed creek 1,100 feet to the south-southeast of the site-which then drains into an
unnamed pond. Drainage in the general area occurs to the southeast toward Irwin Creek. The
Unocal Corporation estimates the groundwater flow velocity in the subsurface at this site is
approximately 12 feet/year. The Unocal Corporation asserts that if no natural degradation or
attenuation of the plume occurs at this site, the plume of dissolved petroleum hydrocarbons
would impact the unnamed creek, the water well in use at B & B Leather (WSW-2), and the
inactive water supply wells at concentration levels exceeding 15A NCAC 2L .0202 standards for
lsopropyl Ether, 1,2-Dichloroethane, 1-Methyl-Naphthalene, and 2-Methyl-Naphthalene
between 17 and 92 years. The company further asserts that by the time substances in the
groundwater plume reaches the B & B Leather well (22 years), substances are expected to be
degraded via "intrinsic bioremediation" to the extent that they no longer exceed the 15A NCAC
2L .0202 Groundwater Quality Standards. The last observed concentration levels of lsopropyl
Ether, 1,2-Dichloroethane, 1-Methyl-Naphthalene, and 2-Methyl-Naphthalene from routine
sampling in December 1995 and February 1996 were used to determine these projected times
of travel to these receptors.
There are no drinking water supply intakes at surface water bodies located within a ½ mile
radius of the site. Drinking water for the City of Charlotte is obtained from Mountain Island Lake
on the Catawba River twelve miles north-northwest of the site. Except for those well owners
identified in the variance request as those still using wells as drinking water supplies, all other
downgradient properties and other area properties are believed to be supplied drinking water
from the City of Charlotte.
It is highly improbable that public water supply lines will be impacted by this variance.
Numerous water supply lines and other utilities are located in the general area. This piping
ranges from 4:inches up to 16 inches in diameter. The depth to the groundwater in this area
is approximately 6.5 to 10 feet below ground surface during the year. No open excavations exist
on-site that allow access to groundwater. Utilities in the area are typically 3 feet below the
ground surface. Groundwater contamination beneath 2932 Gibbon Road is too deep within the
subsurface to impact these lines.
According to the Unocal Corporation's environmental consultant there are no known
buildings with basements at the site or in the general area that could serve as conduits for the
buildup of explosive, flammable, or toxic vapors from this site.
(2) Allow for the restoration of groundwater without requiring remedial actions in accordance
with 15A NCAC 2L .0106U). The Unocal Corporation has submitted supporting information
demonstrating that the continued application of best available technology will not result in
6
10/7/97 version
significant long term remediation of the site to the Groundwater Quality Standards contained
in 15A NCAC 2L .0202. This is due to the high probability that continued remediation activities
at the site will not significantly reduce contaminant levels below Groundwater Quality Standards
in 15A NCAC 2L .0202. Since discovery of the release on January 14, 1988 the Unocar-
Corporation has disposed of a total of 2,300 tons of petroleum contaminated soil during tank
closure. The soil vapor extraction system (SVE) operated for 7824 hours during 1993 and
1994. The company has continually monitored Total Petroleum Hydrocarbons in soils at this
site using Organic Vapor Analysis (OVA) of the SVE air stream from June 16, 1993 through
September 1, 1994. By 1994 the SVE system was removing hydrocarbons at a rate equal to
or less than one part per million. Deactivation of the SVE system occurred because it was no
longer considered beneficial or cost effective since virtually no substances were being removed
by this cleanup technology. The Unocal Corporation has submitted information showing that
the total mass of vaporous hydrocarbons recovered by the SVE system is estimated at 3,400
pounds which is equivalent to 567 gallons of gasoline. It is also important to note that from
August 17, 1993 through March 20, 1996 the air sparging system operated for approximately
17,500 hours. The company reports that a total of$ 751,863 has been expended to remove
tanks, conduct site assessments, and cleanup soils this site. It is important to note that the
Unocal Corporation has incurred the entire cost of cleanup of this site.
Groundwater analysis of samples from all monitoring wells showed significant reductions
in the concentrations of substances from March 4, 1992 through October 29, 1996. It must
be noted that during the time the soil vapor extraction and air sparging technologies were in
operation from June 1993 through March 1996, the concentrations of Benzene, lsopropyl
Ether, and 1,2-Dichloroethane remained below the 15A NCAC 2L .0202 Groundwater Quality
Standards or detectible limits. It is also important to note that the DEHP concentration in
Monitoring Well #12, which first appeared on August 18, 1995, was not reduced below
detectable limits via a combination of air sparging with soil vapor extraction (SVE). The only
significant reduction in the concentration of DEHP in this well to below detectable limits
occurred after the removal of an additional 300 gallons of groundwater via direct pumping of
Monitoring Well 12 on October 18, 1996.
In order t~ demonstrate that the requirements of the rule cannot be achieved using best
available technology, title 15A NCAC 2L .0113(c)(5) requires that specific technology
considered be identified, the costs of implementing the technology be shown, and the impacts
of the costs on the applicant be provided. On August 18, 1997 the Groundwater Section staff
discussed the potential costs associated with continued cleanup of this site with staff from the
Unocal Corporation's environmental consultant S &ME Incorporated, if the variance were not
granted by the Environmental Management Commission. Mr. Stewart Hines of S & ME
Incorporated stated that he has estimated the total cost of continuing to operate the soil vapor
extraction and air sparging cleanup systems to be approximately $ 20,000 per year. The
Unocal Corporation believes that the low residual concentrations of substances in groundwater
and soils at the site, the lack of any impacts on water supply wells, and the lack of any human
receptors does not warrant the additional expense of continuing remediation with soil vapor
extraction and air sparging.
The Unocal Corporation examined the use of in-situ or enhanced bioremediation for this
site. In-situ or enhanced bioremediation relies on the introduction of nutrients and oxygen to
7
1 -0/7 /97 version
groundwater to assist in supporting the development of a population of microorganisms capable
of breaking down substances into harmless chemicals such that concentrations of substances
are reduced below the 15A NCAC 2L .0202 Groundwater Quality Standards. It must be noted
that the implementation of a cleanup system that relies on in-situ bioremediation will not
remediate concentrations of certain substances which do not readily biodegrade. Substances
have been found at 2932 Gibbon Road that are not likely to degrade if a cleanup plan relying
on in-situ bioremediation were implemented at this site. These substances are chlorinated
compounds (1,2-Dichloroethane and lsopropyl Ether) and semi-volatiles (DEHP, 1-Methyl-
Naphthalene, and 2-Methyl-Naphthalene). The Unocal Corporation has submitted information
supporting their view that conditions at this site are such that the life and growth of indigenous
populations of microbes that may exist in the subsurface will be sustained. The company
believes that "intrinsic bioremediation" is already occurring at this site for those substances that
are readily degradable. The cost to implement in-situ or enhanced bioremediation has been
estimated for this site. If this technology were implemented it would require the company to
expend an additional $ 10,000 to $ 15,000 per year. The Unocal Corporation did not identify
any technology, other than those that have been in use at this site or discussed in this variance,
that would meet the requirements of 15A NCAC 2L .0106U) as "best available technology". The
Unocal Corporation does not believe that the public will benefit from continued cleanup using
present technology at the site or alternatives discussed and that a variance is the most effective
means of dealing with remaining concentrations.
The hearing will be held as follows:
CHARLOTTE
Tuesday, November 18, 1997
7:00 P.M.
Mecklenburg County Courthouse -Criminal Courts Building
2N° Floor -Courtroom Number 2201
700 East Fourth Street
~
Oral Comments may be made during the hearing, or written statements may be submitted to
the agency by December 19, 1997. Written copies of oral statements exceeding three minutes are
requested. Oral statements may be limited at the discretion of the hearing officer.
Please forward comments or information requests to:
David Hance
EHNR-DWQ-Groundwater Section
P.O. Box 29578
Raleigh, NC 27626-0578
Phone: [phone]; Fax: [phone]
Internet E-Mail Address: [e-mail]
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This proposed variance request is available for public inspection at the locations listed below.
Copies may be obtained at each location for a charge of ten cents per page.
9
ATTACHMENT -II
HEARING OFFICER'S REMARKS AND STAFF
PRESENTATION
The written comment period for this variance will close at 12:00 PM (midnight) on
December 19, 1997. I am requiring you to complete the hearing officers report and the
recommendation to the Environmental Management Commission Groundwater
Committee by March 19, 1998. This period of time is ninety (90) days after the closing date
for written public comment and allows Division staff adequate -time to review your
recommendation. Unless significant new site information becomes available after the public
hearing or other extraordinary circumstances occur that dictate a longer review period by the
hearing officer, the earliest date that this variance may be considered by the Groundwater
Committee is February 12, 1998. If your review of the variance shows that there is a need
for a longer evaluation period, please contact Arthur Mouberry at [phone].
I appreciate your taking the time to conduct this hearing. The staff will be glad to
assist you through the proceedings. If you have any questions, feel free to call Carl Bailey at
[phone] .
Attachments.
cc: Arthur Mouberry
Carl Bailey
David Hance
2
Public Hearing-Variance Request
November 18, 1997
Variance to 15A NCAC 21 .0202 and 15A NCAC 21 .0106G)
2932 Gibbon Road, Charlotte, North Carolina (Derita Community)
(Groundwater Incident Number 3751)
HEARING LOCATED AT:
Mecklenburg County Courthouse
Criminal Courts Building -2nd Floor, Courtroom 2201
700 East Fourth Street -(at 7:00 PM)
HEARING OFFICER'S SPEECH
HEARING OFFICER: Tommy Stevens, Division of Water Quality, Regional
Supervisor (Fayetteville Regional Office)
~~QQ~IC~~: GOOD EVENING, I WOULD LIKE TO CALL THIS
PUBLIC HEARING TO ORDER. MY NAME IS TOMMY STEVENS, AND I AM
THE DIVISION OF WATER QUALITY (FORMERLY THE DIVISION OF
ENVIRONMENTAL MANAGEMENT) REGIONAL SUPERVISOR IN THE
•
FAYETTEVILLE REGIONAL OFFICE. I HAVE BEEN DESIGNATED HEARING
OFFICER FOR THIS EVENING'S HEARING.
THIS HEARING IS BEING HELD PURSUANT TO NORTH CAROLINA
GENERAL STATUTE 150B-21.2. IN ACCORDANCE WITH THE GENERAL
STATUTES, A PUBLIC NOTICE OF THIS HEARING WAS PUBLISHED IN
1
CONFORMITY WITH 15A NCAC 2L .0113 OF THE GROUNDWATER RULES
AND GENERAL NOTICE HAS BEEN GIVEN IN THE LOCAL PAPER
ACCORDING TO PROCEDURES IN 15A NCAC 2L .0113(e)(l-1. NOTICES WERE
ALSO DISTRIBUTED TO-THE PUBLIC AT LARGE, LOCAL GOVERNMENT
OFFICIALS, WELL OWNERS, AND PROPERTY HOLDERS WITHIN AND NEAR
THE AREA OF THE PROPOSED VARIANCE. THE PUBLIC NOTICE STATED
THAT A MORE DETAILED SUMMARY OF THIS VARIANCE COULD BE
OBTAINED FROM STAFF AND COPIES OF THIS SUMMARY ARE BEING
MADE AVAILABLE TO PERSONS ATTENDING THIS HEARING TONIGHT.
THE PURPOSE OF THIS HEARING IS TO OBTAIN PUBLIC COMMENT AND
PARTICIPATION IN THE CONSIDERATION OF THE VARIANCE REQUEST
FOR THE UNOCAL CORPORATION OF ATLANTA, GEORGIA. THE UNOCAL
CORPORATION IS REQUESTING THIS VARIANCE FROM RULES CONTAINED
IN 15A NCAt 2L GROUNDWATER CLASSIFICATION AND STANDARDS FOR
THE PROPERTY LOCATED AT 2932 GIBBON ROAD. THIS PROPERTY,
PREVIOUSLY OWNED BY THE UNOCAL CORPORATION, IS NOW OWNED
BY MR. FRANK DWYER OF CHARLOTTE, NORTH CAROLINA. UPON
TANK REMOVAL AND SITE RENOVATION BY THE UNOCAL
CORPORATION, MR. DWYER BEGAN TO OPERATE A BUSINESS AT THIS
2
BIS (2 ETHYLHEXYL)PHTHALATE (ALSO KNOWN AS DEHP} FOUND BY
THE U.S. ENVIRONMENTAL PROTECTION AGENCY METHOD 625 IN
MONITORING WELL# 12 WILL REMAIN AT THE 7ffl;1 REM~N Nf TM
CONCENTRATION LEVEL FOUND AS ANALYZED ON OCTOBER 28, 1996.
THESE CONCENTRATIONS WILL BE REQUIRED TO REMAIN WITHIN THE
PROPERTY BOUNDARIES OF 2932 GIBBON ROAD. THE UNOCAL
CORPORATION ALSO PROPOSES THAT CORRECTIVE ACTIONS REQUIRING
THE APPLICATION OF BEST AVAILABLE TECHNOLOGY IN 15A NCAC 2L
.0106 (j) NOT BE APPLIED TO THE AREA WITHIN THE BOUNDARIES OF THE
PROPOSED VARIAN CE. THE UNOCAL CORPORATION HAS REPORTED
THAT A TOTAL OF $ 751,863 HAS BEEN EXPENDED TO CLEANUP THIS
SITE. NO CLAIMS FOR REIMBURSEMENT THROUGH THE STATE'S
COMMERCIAL UNDERGROUND STORAGE TANK TRUST FUND HA VE EVER
BEEN FILED BY THE UNOCAL CORPORATION FOR THIS SITE. THE
UNOCAL CORPORATION HAS SUBMITTED SUPPORTING INFORMATION
DEMONSTRATING THAT THE CONTINUED APPLICATION OF BEST
AVAILABLE TECHNOLOGY WILL NOT RESULT IN SIGNIFICANT LONG
TERM REMEDIATION OF THE SITE TO THE GROUNDWATER QUALITY
STANDARDS IN 15A NCAC 2L .0202. THE COMPANY BELIEVES THAT
APPLICATION OF BEST AVAILABLE TECHNOLOGY AT THIS LOCATION IS A
4
SERIOUS FINANCIAL IMPACT WITHOUT EQUAL OR GREATER PUBLIC
BENEFIT.
THIS HEARING WILL CONFORM TO PROCEDURES IN 15A NCAC 2L
.0113. ADDITIONAL COPIES OF THE NOTICE OF VARIANCE APPLICATION
AND HEARING ARE LOCATED IN THIS BUILDING AND ARE AVAILABLE
FOR PUBLIC REVIEW.
A WRITTEN RECORD OF THIS HEARING WILL BE PREPARED WHICH
WILL INCLUDE ALL THE RELEVANT COMMENTS, QUESTIONS, AND
DISCUSSIONS. FOR THIS REASON, THE HEARING IS BEING TAPE
RECORDED. WRITTEN COMMENTS RECEIVED THROUGH DECEMBER 19,
1997 WILL ALSO BE INCLUDED IN THE RECORD. BASED ON THESE
PUBLIC COfy.lMENTS AND ON ANALYSIS BY THE GROUNDWATER STAFF, I
WILL MAKE A RECOMMENDATION TO THE ENVIRONMENTAL
MANAGEMENT COMMISSION. IN MAKING THE FINAL DECISION, THE
ENVIRONMENTAL MANAGEMENT COMMISSION CONSIDERS THE
WRITTEN RECORD, THE RECOMMENDATION OF THE HEARING OFFICER,
THE RECOMMENDATIONS OF DMSION STAFF, AND THE CONCERNS OF
5
ITS MEMBERS. THE COMMISSION MUST ALSO CONSIDER WHETHER THE
APPLICANT HAS COMPLIED WITH 15A NCAC 2L .0113(g).
IF THE APPLICANT DECIDES THAT THE COMMISSfON'S DECISION IS
UN ACCEPT ABLE, A PETITION MAY BE FILED ACCORDING TO
PROCEDURES IN 15A NCAC 2L .0113(h). THE DECISION ON THE VARIANCE
BY THE ENVIRONMENTAL MANAGEMENT COMMISSION IS FINAL AND
BINDING ACCORDING TO THE CONDITIONS SHOWN IN 15A NCAC 2L
.0113(h).
AT THIS TIME I WOULD LIKE TO RECOGNIZE (names of local and state
officials) AND THANK YOU FOR ATTENDING THIS HEARING. I WOULD ALSO
LIKE TO RECOGNIZE THE FOLLOWING PEOPLE FROM THE DIVISION OF
WATER QUALITY (DWQ central office and DWQ regional office personnel).
1)«:v~ Hctl'\c.c-1 If l~r\ Sc.~.., <;Sr
S"ck~ ..
MR.(siaff s,ealier) OF THE DMSION OF WATER QUALITY-GROUNDWATER
SECTION MOORESVILLE REGIONAL OFFICE WILL NOW SUMMARIZE THE
PROPOSED VARIANCE WHICH IS THE SUBJECT OF THIS HEARING.
STAFF SPEAKER: (staff speaker summarizes variance request).
6
ll~A:RlliG Offl~B: THANK YOU [last speaker]. ARE THERE ANY MORE
COMMENTS? SINCE THERE ARE NO MORE COMMENTS, I DECLARE THE
HEARING CLOSED. THE HEARING RECORD WILL REMAIN OPEN UNTIL
12:00 PM (MIDNIGHT) ON DECEMBER 19, 1997. ANYONE WISHING TO
SUBMIT WRITTEN COMMENTS MAY DO SO UNTIL THAT DATE. AFTER
.WHICH TIME, THE COMMENTS WILL BE MADE PART OF THE PUBLIC
RECORD AND I SHALL MAKE RECOMMENDATIONS TO THE
ENVIRONMENTAL MANAGEMENT COMMISSION. WRITTEN COMMENTS
MUST BE ADDRESSED TO DAVID HANCE AT THE DMSION OF WATER
QUALITY GROUNDWATER SECTION. THE ADDRESS WRITTEN COMMENTS
NEED TO BE SENT TO IS SHOWN IN THE PUBLIC NOTICE AND IS AS
FOLLOWS:
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David Hance
EHNR-DWQ-Groundwater Section
P.O. Box 29578
Raleigh, NC 27626-0578
A FACSIMILE COPY OF WRITTEN COMMENTS MAY BE SENT TO MR.
HANCE BY DIALING [phone]. HIS TELEPHONE NUMBER IN RALEIGH
IS [phone]. COMMENTS MAY ALSO BE SENT TO MR. HANCE VIA E-
MAIL BY CONTACTING HIS INTERNET MAILING ADDRESS SHOWN IN THE
PUBLIC NOTICE.
8
HEARING OFFICER: THANK YOU. WE WILL NOW ACCEPT PUBLIC
COMMENT ON THE PROPOSED VARIANCE. I WOULD LIKE TO REQUEST
THAT EVERYONE FILL OUT A REGISTRATION FORM. AFTER ALL
REGISTERED SPEAKERS HA VE HAD AN OPPORTUNITY-TO COMMENT, I
WILL ALLOW ADDITION-AL SPEAKERS AS TIME PERMITS. WHEN YOUR
NAME IS CALLED, PLEASE COME UP TO THE MICROPHONE AND STATE
YOUR NAME AND AFFILIATION. ALL COMMENTS SHOULD BE LIMITED
TO MATTERS THAT ARE RELATIVE TO THE PROPOSED ADOPTION OF THIS
VARIANCE. IF YOUR COMMENTS ARE LONGER THAN THREE MINUTES, I
WOULD LIKE TO REQUEST THAT THEY BE SUBMITTED IN WRITING. I
RESERVE THE RIGHT TO QUESTION SPEAKERS IF THE NEED SHOULD
ARISE .
DIVISION OF WATER QUALITY STAFF WILL BE AVAILABLE TO ANSWER
YOUR QUESTIONS IF NECESSARY. I WOULD NOW LIKE TO CALL [first
speaker]. !
[speakers ... ]
(the hearing officer, referring to THE REGISTRATION CARDS, calls each speaker to the
microphone in turn )
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IT IS THE DESIRE OF THE COMMISSION TO ALWAYS ACT IN THE BEST
POSSIBLE INTEREST OF THE PUBLIC. THEREFORE, PUBLIC
PARTICIPATION IS A VERY IMPORTANT PART OF THE RULE-MAKING
PROCESS. I WOULD LIKE TO THANK YOU FOR ATTENDING THE HEARING
AND OFFERING YOUR COMMENTS.
9
Directions to Variance Hearing for the Unocal Corporation
(Site located at 2932 Gibbon Road in Charlotte, NC {Derita Community})
HEARING LOCATED AT:
Mecklenburg County Courthouse Criminal Courts Building -2nd Floor, Courtroom 2201
700 East Fourth Street, Charlotte, NC (November 18, 1997 at 7:00 PM)
MOORESVILLE REGIONAL OFFICE STAFF PRESENTER:
Allen Schiff [phone]; fax -(70-4) 663-6040
RALEIGH GROUNDWATER SECTION STAFF RECORDER:
David Hance [phone]; fax-[phone]
HEARING OFFICER: Tommy Stevens [phone]
CONTACT PERSONS AT THE COURT HOUSE -
SGT. PHIL MCGUIRE -[phone]
CAPT. DEATON -[phone]
MAIN NUMBER FOR SHERIFF'S OFFICE -[phone]
FROM FAYETTEVILLE NC:
Take US 401 to Laurinburg, North Carolina and then take US -74 west to Charlotte, NC.
Take US 74 -NC 27 (East Independence Blvd) in the City of Charlotte. Take NC 27 and
get onto McDowell Street. Turn left on McDowell Street and proceed three city blocks
then turn onto East Trade Street. The Criminal Courts Building is located adjacent to the
Government Center. NOTE: East Fourth Street is a one way street going east to west.
East Third Street is a one way street going west to east.
FROM RALEIGH, NC:
,.
Take 1-85 into Charlotte and exit onto NC 16 (Brookshire Freeway). NC 16 will become
1-277. Take 1-277 to S. Graham Street and then go onto East Trade Street. The Criminal
Courts Building is located adjacent to the Government Center. NOTE: East Fourth
Street is a one way street going east to west. East Third Street is a one way street going
west to east.
(See Attached Map)
,
Nov 18 '97 P.03104
Page Two
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• The.soil vap~r extracti◊n system:w~s actiyated on July 16, 1993 and ~as
nm until September: 22, 1994. · ·
• Theair:sp-arging.syst~~ w~'a~tiva.ted onjAugu~-17, 1993, and deacti.vated ;!
on March20, 1996. __ .. · :. . .<. : j
.. I ;
~ ; '' 'The Grouiidwater ~; the si~~ ~a~,b~e.n~o~~ored°(quartedy then se~·. '. .' '~
', · · · ~uallyY s~nce. March 4, . ·1992, .wi~h the Jarest sampling h~ving .o.fXtiried· on: , · · 1 [!
.: ... ·: August:21;_"199_1:. :ou~g this.s~pling.":~ve~t.oniy c~k,rofonn.-·_at 4._55."ppm· ·_/.! ~
.0: /I
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:'in MW~-l J° was: fbund io:· eicceed Jhe: grouJdwaJer .stand,ard·s found i~' l :SA ' ' .·-: ·i '
,,···NcAG~. ·In_.addttion, bis(2·~~thyte.hexyl~-ph~alate;'_whi~h·ha:s.no: · ~ .. ·.:: · : :I : ~.
·. groundwater standard:was:'found.;as high as 48'~3:pph--iii'incinitor,wenMw.:; . ,i · ~ ·.·
\ o: .·· ...... · .. •···· . it .• ·······.·• : ; : .. • •· . t ·.·· ... ·· .. ·.· . · ...... · .. • > . ' i J
·• · · : Qrm,mchvateri has _be~n:_ determi1:1e~ -to .tlowgeriefally Jo,:th;e-southw~st.. :. · !
. "' . '.,, ,• . •.
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• :'.:· ::.-,)11.e· ciose~!,ecept0;r:is.~e actiye:w.e~ at-¥~-~B.Le_atb~r-C,oin~any· (·. ·! ~ .· < .. lpcated_JSO f~t east-nort~eas;t: ofthe:Un~cal_.property Un~. The YJ~-~' ~ . • i
. . ·.beeri-.co_n~~up~s~y s:a.mpl~~ ~~n9e J\pril19~3 and hafneve~-exhibited any ~
.. · ·-.contamination; : · , .. · . · ,. ·. •. : : · · i'· · ,i
1
:
1 : . . . . ·: , . . . ·, ,.. ·. ::'.. . . . . . l . , t ii!
•· ... ·The ne~ cJos~st w~ll)~ lo~ated ~t·G~blrP~Det .. Co~pany anti"is 3'7~ f~et< ·. i ~ ~;;
: ' ':: :·. west-:~flhe.:un·otalJ>fopeffy :t~nie~ Thew~~ ~as ~so-been contil)Uo~~ly .·.. . ( :, ..:-~ \:
:_ : ':,sanipled.whb no petroleum contaminabo~ e\'.eF having beeri obser.v.ed.· ' ,, 'i f :::
· .. ·· :1~w te~els ofthe··tetr~chl,or~t~ape .has ~ieJl _obst":n,ed.~_~eveial ~r~vi~u( .• .-. ! .-~-
··., ·. :.5a~pies. but·is:~~l~te'd;to. Un~cal~ rel~fe ... · .. . . . . . . .. ,. ., ,.,_,,1 . ~:. ;;:
, . . . . . .... ·":. . .... . ·f .. . . . . . ' l:i
. .. •,' ·•. ~. _,.:_::•.:!11: a~diticm'..a tot,rdtfotty ~i~ht._.~ainpn~1·a~i~~--b~·m_a:ctiv~.~~s;~~--·.;:_ · ·.;::.:: . ~ . 1::
, .. ,.... . . -·. ~1thin ½-ID!lle of t_he: sit~ .. .:Many: oft~ese·.propc:rt:ies ~e-~\s<>.-servi.ced.~~~ : .. : · ! tJ ,.,
:: city water~ '" ' ' . ' " " ' ,,: ' ' . ' ' ' ' ~ ,: : ~ r~ ..
: :: 'f~e ·ci,o';est surface .w~ter-.body is an:µ~µied ·cr~ek k1¢ated il 00 feei tq ! : i .. :· ;::
. ·thesoutb~est·;-.• .. ·:··<: .· ,· .. )_::_J.::_' ... : :·.. ·· ... : If .
. • ~ •,. . , . r ) l'il'
... ':,. . . ·.. . .. . ' .. :. . : '. ,'. ~·· ·: ·. ·, .. . . i ' . ' .,... . . ' . ' . . . ' . . ' ; ' ii
. . • . . ·: Uno~al' ,hc1;s. sul>mitt~d-avaria~ce,-regu,est and' supporting-_~fo~atio_n .-~. · .. : .. · · ! .-·.,·: : : .. r: ·· •··•·• : .•. · :· :t.r.:~~~::::t:;~;#~t~;~::,t:z-:: ; •·i ·· !
:·'.·· . • .. :". ,... with}SA,NCAC~L:-0~06G},~lJnotr~S11ltin_'s1gnifi~ant_longterm ...... ·. -.'.:}.
. . ·. · .. ·'reme~iation of the_ site· to: the· groundw~t~r stanq~ds. corit~ined .. in 15 A·•. -,.. , : ' .. J ~
. :· · ·'·, ·''NCAC 2L oio2 ·: ·.· . .-· . . . ,.:;,·•, . . .. : . ·, ~ . : .. . . . -l·. ) ~
: .. :"·.'·
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Page Three
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Nov 18 '97 P. 04.ttl4 -
• To support thei,r claim; lJnocal has submitted the following facts and
financial information:
1.
2.
.The · remediation-sy~em has extracted a total · of approximat~Jy 3400
pQunds .of.p~tfoleumhydrocarbons frqm soil and ground~ater: ,.
_ Uno_cal has ~xpenl;fe<i'.$.796,532.0ff as: ofNov_e111ber 1_997, none Of· .
. whichis: r~imb~rsable ·fro~·ihei sta.~e _ trust n:incf. . . . , .. ; . n
: • ri
l: :-: : ::· 'Has--s~wn-_ih~t when the t~eatm~nt ~stem IS c,ff, 'that~o-in~ease ·,
·m -gr~undwater c~tam,4-iants _has:dccurred. · ' · -...
'• .4 .
,,, ',, . '· ·,
. .. ::.: ,: __ :: ·. .• . ' i
'.Ihat the irriplep'lentat!Oll or CODtinued u~ of air spargjng a~ :S.VE : ,;-' :
. _ ,>snot eoonomica_lly_ reasonable or practic.at, particularly~ sfu~e the: ·.:-.._: '·:!
-· site for all irit~nts ~ ptirposes •is-clean. _· ·_ .. . . . . ~ . · .. ,;
.• .. . . . . ' . . ' ' '
· .. No futur~ -gr<>µndwaier· -~plin.g ··•s pro~os~d q-r recoromen.Eiecj-for .,the '.
former-U.ti9cahite-.· .. · .. ·-. . . ·--.. . -. . .
ATTACHMENT -III
PUBLIC COMMENT FOR UNOCAL VARIANCE
AT 2932 GIBBON ROAD IN CHARLOTTE, N.C.
(DERITA COMMUNITY)
GROUNDWATER INCIDENT NUMBER 3751
ATTACHMENT-IV
VARIANCE REQUEST WITH A RATIONALE
(CONTAINS THE MEMORANDA AND EXECUTIVE SUMMARY REPORT SUBMITTED
TO THE DIVISION BY THE UNOCAL CORPORATION'S ENVIRONMENTAL
CONSULTANT
S&ME, INCORPORATED)
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VARIANCE REQUEST
INCIDENT NO. 3751
UNOCAL CORPORATION
FORMER UNOCAL STATION #9342-811
DERITA, NORTH CAROLINA
S&ME PROJECT NO. 1354-92-667
Prepared For:
Chairman of the Commission in Care of the Director
Division of Environmental Management
P. 0. Box 29535
Raleigh, NC 27626-0535
Prepared By:
S&ME, Inc.
9751 Southern Pine Boulevard
Charlotte, NC 28273
June 1996
•OeGPac,a
t .,
June 13, 1996
Chairman of the Commission in Care of the Director
Division of Environmental Management
P.O. Box 29535
Raleigh , NC 27626-0535
Attention: Mr. Preston Howard
Director
Reference: VARIANCE REQUEST
INCIDENT NO. 3751
Unocal Corporation
Former Unocal Station #9342-811
Derita, North Carolina
S&ME Project No. 1354-92-667
Dear Mr. Howard:
S&ME, Inc. (S&ME), on behalf of Unocal Corporation (Unocal), submits this variance
request in accordance with 15A NCAC 2L .0113(b) through (d). The site is known as the
Unocal-Derita site and the state groundwater incident number is 3751 . Unocal has
aggressively acted to reduce hydrocarbon levels at this site between 1991 and 1996. The
site is not eligible under the Commercial Trust Fund Reimbursement Program .
. Unocal excavated the majority of gasoline contaminated soil (2,300 tons) beneath the site
during the tank closure in September 1991. Unocal completed a Comprehensive Site
Assessment (CSA) Report, which defined the extent and magnitude of the 1987 gasoline
re lease . Unocal also submitted a Corrective Action Plan (CAP) for air sparging and vapor
extraction in December, 1992. The State approved the CSA and CAP in 1992 and 1993,
respectively. Unocal operated an in-situ soil vapor extraction (SVE) system from July,
1993 through September, 1994. Unocal also operated an in-situ air sparging (AS) system
from August, 1993 through March, 1996. This active remediation and natural
S&ME, Inc . 9751 Southern Pine Boulevard . Charlotre, North Carolina 28273, [phone]. Fax [phone]
Mailing address: P.O . !3ox 7668 , Charlotte, North Carolina 28241-7668
_7
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NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
bioremediation has resulted in reduction of the gasoline plume extent and magnitude by
over 95%, as indicated in Table i -Historical Groundwater Quality Data.
Both SVE and AS remediation systems have reached the practical limits of their use, as
most subsurface gasoline ccintalning soil, groundwater or vapors have been removed and
continued remediation is not expected to significantly reduce the potential impact to public·
health and the environment. Furthermore, intrinsic bioremediation is occurring such that
remaining low levels of dissolved hydrocarbons are expected to be naturally degraded
before reaching the nearest hydraulically downgradient receptor. The closest receptor
to the site is the active B&B Leather Company private well located 150 feet east-northeast
of the nearest Unocal site property line, (see Figure 4). The B&B Leather well has never
exhibited groundwater contamination, as indicated in Table 1. The second closest private
well is the former Gamble Pallet Co. well (inactive) located 375 feet west of the nearest
Unocal site property line. The Gamble Pallet Co . well has exhibited low levels (4 .06 to
9.28 ug/L) of tetrachloroethene during four semi-annual sampling events, which is
unrelated to the Unocal gasoline release of 1987.
Considering (a) the current low dissolved gasoline levels ( < 1 ug/L BTEX), (b) no of-site
plume migration , and (c) that no drinking water supply wells have been impacted by the
Unocal gasqline release, continued remediation is not expected to significantly reduce the
potential impact to public health and the environment. Since the dissolved phase BTEX
is absent from all wells on-site or off-site, there is little risk of BTEX migration. S&ME
requests that no further remediation be required at this site and that a Variance be
granted for the surficial aquifer beneath the former Unocal-Derita site. Additionally,
laboratory (carbon tube) and organic vapor analyzer (OVA) results of vapor influent
samples collected during operation of the vapor extraction system indicate that total
petroleum hydrocarbons (fPHs) in the unsaturated soils have been reduced to 0.1 ppm
or less.
2
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FIGURES
1 SITE LOCATION AND TOPOGRAPHIC MAP
2 SCALED SITE MAP WITH MONITOR WELLAND REMEDIATION SYSTEM LAYOUT
3 CITY OF CHARLOTTE TOPOGRAPHIC MAP OF SITE VICINITY
4 MECKLENBURG COUNTY TAX MAP OF SITE AND ADJACENT PROPERTIES
5 VISTA MAP OF ENVIRONMENTAL RISK SITES WITrllN ONE MILE OF SITE
6 WATER WELL SU8VEY MAP (MAY 28, 1996)
7 BTEX ISOCONCENTRATION MAP & GROUNDWATER FLOW IN FEBRUARY 1996
TABLES
1 HISTORICAL GROUNDWATER QUALITY
2 GROUNDWATER SURFACE ELEVATIONS
CHARTS
1 SVE INFLUENT CONCENTRATIONS (TPH AND OVA) TO DATE
2 BTEX IN GROUNDWATER -1992-1996 (MW-3,9,10,12,14;RW-1&2)
3 BTEX IN GROUNDWATER -1992-1996 (MW-1,2,6,11,13,15,RW-3&4)
4 MTBE IN GROUNDWATER -1992-1996 (MW-3,9,10,12,14,RW-1&2)
5 MTBE IN GROUNDWATER -1992-1996 (MW-1,2,6,11,13,15,RW-3&4)
6 601 ANALYTES IN GROUNDWATER -1992-1996 (MW-1,2,6,11,13,15,RW-3&4)
7 601 ANALYTES IN GROUNDWATER -1992-1996 (MW-3,9,10,12,14,RW-1&2)
8 625 ANALYTES IN GROUNDWATER -1992-1996 (MW-1,2,6,11,13,15,RW-3&4)
9 625 ANALYTES IN GROUNDWATER -1992-1996 (MW-3,9,10,12,14,RW-1&2)
APPENDl<=:ES
'
1 GROUNDWATER QUALITY DATA ON 4/24/96
2 BTEX AND MTBE GROUNDWATER PLUME MAPS TO DATE FOR THE UNOCAL
SITE (1992-1995)
3 STATIC AND SPARGING GROUNDWATER FLOW MAPS (1988-1995)
4 WATER WELL SURVEY WITHIN 0.5-MILE RADIUS OF SITE
5 FINANCIAL INFORMATION OF COST TO DATE FOR PROJECT
6 PROTOCOL FOR MONITORING INTRINSIC BIOREMEDIATION IN
GROUNDWATER, MARCH 1995, CHEVRON CORPORATION PAPER
7 ECOVAC ENHANCED FLUID RECOVERY FIELD DATA SHEET
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
1 INTRODUCTION
1.1 Reports Submitted to State
S&ME Project No. 1354-92-667
June 13, 1996
The following reports have been prepared for the site and submitted to the Groundwater
Section of the North Carolina Department of Environment, Healtl:l and Natural Resources
(NCDEHNR), Mooresville Regional Office: (1) A Tank Closure Report Dated October
1991, (2) A Comprehensive Site Assessment Dated June 2, 1992, (3) A Corrective Action -
Plan Dated December 23, 1992, and (4) numerous quarterly air quality reports and semi-
1 ... annual groundwater quality reports submitted since 1992.
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1.2 Permits Issued by the State or County
No permits were issued to this site by the State, except for monitor well installation.
Permits were not required by the State for construction and operation of the SVE and AS
remediation systems. The vacuum for the SVE system was registered with the state as
an air emission source. An air quality permit No. 93-027-855 was issued to Unocal
Corporation (Unocal) on March 24, 1993 and voided on October 17, 1994 due to the
deactivation and proposed removal of the SVE system and the de minimis uncontrolled
emissions of volatile organic compounds from the groundwater remediation activity .
1.3 Recent State Correspondence Concerning Remediation System
The most rec-ant correspondence from the NCDEHNR-Mooresville Regional Office (MAO)
relative to our February 16, 1996 Request For Site Closure was dated April 1, 1996, and
stated that "At this time Unocal could request a variance or propose a risk based CAP in
accordance with 15A NCAC 2L .0106 (k,I or m) but a site closure is at this time not a
viable option." A "clean" closure is inappropriate due to: (a) the site conditions do not
meet the closure requirements specified in the March 1993 "Groundwater Section
Guidelines For The Investigation and Remediation of Soils and Groundwater", and (b)
slight exceedances of the 2L groundwater standards at MW-6, MW-9, MW-10, MW-12 and
RW-2. The April 1, 1996 letter also suggested sampling groundwater from monitor wells
4
NCDEH N R-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
converted to either vacuum or air sparging wells (MW-3, RW-1 and RW-2) for additional _
water quality data.
1.4 Groundwater Sampling-Event of April 24, 1996
S&ME sampled groundwater from MW-3, MW-10, RW-1, RW-2 and RW-4 for Method 601,
602 extended and 504 .1 analyses on April 24, 1996. Groundwater from former
vacuum/sparge well RW-3 was not sampled, since groundwater from adjacent monitor
well MW-2 has always been "clean". This groundwater sampling event was performed in
response to the State's April 1, 1996 letter and to update groundwater quality data, as
part of this Variance Request. Groundwater levels were measured prior to sampling on
April 24, 1996 (Table 2) .. The groundwater samples were analyzed by Flowers Chemical
Laboratories, Inc . of Altamonte Springs, Fl (NC Certification #296). The laboratory results
are included in Appendix 1.
The April 24, 1996 analytical results revealed no measurable dissolved hydrocarbons in
groundwater from RW-2, RW-4 and MW-3. MTBE was only detected in MW-10 (83.2
ug/L) and RW-1 (24 .. 1 ug/L).
1.5 Historica~ Groundwater Quality Data
Historical groundwater quality data indicates that the dissolved hydrocarbon plume has
decreased progressively in size and severity. Appendix 2 includes all benzene, toluene,
ethylbenzene, and total xylene (BTEX) plume isoconcentration maps to date for the site,
which illustrate initial plume configuration before remediation and after remediation. Figure
7 also illustrates the BTEX concentration map for groundwater on February 25 and 26,
1996. The February, 1996 sampling event was the last semi-annual groundwater
sampling event of all wells for Class I hydrocarbon parameters, as required by the State.
Groundwater sampling for Class II hydrocarbons is performed in August, 1995 as required
by the State. The February 1996 l~boratory results indicate that all Class I and II
5
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NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
hydrocarbon compounds were below 2L groundwater standards, except as follows: off-
site monitor well MW-6 [6.43 ug/L of Bis(2-ethylhexyl)phthalate], and on-site monitor wells
MW-9 [2.02 ug/L of isopropylether (IPE) and 3.6 ug/L of 1,2-dichJoroethane (1,2-DCA)],
MW-12 [578 ug/L of bis(2-ethylhexyl)phthalate], and RW-2 [4.55 ug/L of 1-methyl-
naphthalene, 2.69 ug/L of 2-methyl-naphthalene, and 4.08 ug/L of bis(2-
ethylhexyl)phthalate J.
The 2L groundwater violations at MW-6 may be from a new non-gasoline release at the
Handry Pantry or nearby, as this well has been free of dissolved gasoline type
hydrocarbons from March 4, 1993 through February 25, 1996, as indicated in Table 1.
The methylene chloride and bis(2-ethylhexyl)phthalate detected in groundwater from MW-
6 are believed to be unrelated to the Unocal gasoline release of 1987. No hydrocarbon
release has been recorded by the NCDEHNR-Mooresville or Raleigh Offices for the
Handry Pantry store #72 at 2947 Gibbon Road, Derita, NC. In addition, the bis(2-
ethylhexyl)phthalate detected in deep (Type Ill) monitor well MW-12 may be from an off-
site source and is believed to be unrelated to the Unocal gasoline release of 1987. Bis(2-
ethylhexyl)phthalate is a plasticizer and may be from sampling equipment (i.e. latex gloves
or polyethylene bailers). Another possible source of the bis(2-ethylhexyl)phthalate is from
dissolved plastic or a-rings inside the oil coalescing filters and other sparge controls.
~
The low levels o(dissolved hydrocarbons [i.e. benzene (0 .784 ug/L), MTBE (83.2 ug/L),
IPE (2.02 ug/L), 1,2-DCA (3.6 ug/L), bis(2-ethylhexyl)phthalate (578 ug/L), naphthalene
(1.22 ug/L), 1-methyl-naphthalene (4.55 ug/L), and 2-methyl-naphthalene (2.69 ug/L)]
in groundwater are confined to the former Unocal site and do not appear to be migrating,
as evidel")ced by the "clean" peripheral wells MW-1, MW-2, RW-4, MW-13, MW-14 and
MW-15. Dissolved gasoline compounds in groundwater are defined vertically in the deep
bedrock well MW-12.
6
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NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
wells exhibiting low dissolved hydrocarbon concentrations. MTBE concentrations at MW-
1, MW-2, MW-6, MW-11, MW-13, MW-15, RW-3, and RW-4 decreased from > 10 ug/L to
< 5 ug/L. All MTBE concentrations in groundwater from on-site and off-site wells
monitored are below 100 ug/~-BTEX and MTBE concentrations in groundwater on-site
in all monitor wells sampled, are below State 2L levels based on the February 1996
sampling event.
Dissolved concentrations of IPE and EDB at all monitor wells, except for the 2.02 ug/L
concentration of IPE at MW-9, are also below quantitation limits and thus are below State
2L standards. Groundwater analyses from the closest hydraulically downgradient private
water well (B&B Leather) have revealed no Class I or II hydrocarbon concentrations
above State 2L standards. The B&B Leather well is the only active private water well
adjacent to the Unocal site .
Trace levels of EPA Method 601 compounds and Method 625 compounds were detected
during the December, 1995 sampling event, as indicated in Table 1. All other Method 601
and 625 compounds were below quantitation limits or State 2L standards for the last
sampling event. Charts 6 and 7 illustrate that concentrations of Method 601 compounds
are either below detection levels or less than 4 ug/L in all wells, based on the last semi-
"
annual groundwater sampling event (February 1996). Charts 8 and 9 illustrate that
concentrations of Method 625 compounds are either below detection levels or less than
10 ug/L in all wells, except MW-12. Unocal is continuing to remediate the area of MW-12
by periodic vacuum pumping from MW-12. The concentration has been reduced from
2700 ug/L (8/95) to 578 ug/L (12/95) as a result of periodic pumping. Methylene
chloride, chloroform and bis(2-ethylhexyl)phthalate are not constituents of gasoline, _diesel
or kerosene which was previously stored on-site.
11
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NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
Only one off-site monitor well (MW-6 at the Handy Pantry gas station) showed an increase
in dissolved hydrocarbons (methylene chloride). Methylene chloride was not detected
during the February, 1996 event. Methylene chloride is a comm~m laboratory artifact and
the presence at MW-6 is suspected to be from an off-site source. Table 2 indicates that
groundwater quality MW-6, MW-11 and MW-12 was relatively "clean" for Class I and II .
hydrocarbons in 1992, 1993 and 1994 ( after the Uno cal release). The wells started
exhibiting low to moderate concentrations of Method 601 and 625 compounds in 1995,
which could be a~sociated with either an off-site release, a laboratory artifact and/or
contamination from sampling products (i.e. plasticizer used in latex gloves). A copy of
the latest (April, 1996) groundwater sampling results is attached. All soil vapor and
groundwater analyses were performed by Flowers Chemical Laboratories (NC lab
certification #296).
2.3 Existing Activities
The site is currently operated as Dwyers Auto Repair. No gasoline, diesel, kerosene or
any petroleum fuel is sold on-site, and all UST systems have been removed. There are
currently no primary sources of hydrocarbons on-site, since the UST systems and
contaminated soils have been removed or remediated. Only a minor secondary source
of groundwater containing low concentrations of dissolved semivolatiles exist in the
~
immediate are'a of the former UST pit on-site , See Table 1. No other present or potential
sources of groundwater contamination are known on-site or at any of the adjacent
properties. There are no known proposed activities or planned operations for the former
Unocal site that would result in further discharge of contaminants to the groundwaters
beneath the site. The existing small groundwater plume of relatively low hydrocarbon
concentrations is naturally degrading by intrinsic bioremediation, as discussed in Section
4.1 .
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NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
4 VARIANCE WILL NOT ENDANGER THE PUBLIC HEAL TH AND SAFETY
The closest active private water well to the site (B&B Leather well) has not indicated
groundwater contamination for the eight sampling events betw~en 1993 and 1996 (Table
1). In addition, none of toe other surrounding private water wells, which have been
sampled (Inactive Delta Unit Rebuilders well, Inactive Durane Gas well and Inactive
Gamble Pallet well) have ever exhibited dissolved gasoline compounds from the Unocal
release. Most residences and businesses within a 0.5-mile area obtain their water from
CMUD. Depth to groundwater is approximately 6.5 to 10 feet below ground during the
year. There are no open excavations on-site that allow access to groundwater. There
are no known subsurface utilities within the groundwater, thus, there is little no potential
for groundwater plume migration along utilities. There are no air or surface exposure
pathways for the dissolved hydrocarbon plume. The potential groundwater exposure
pathway is also very low as evidenced by the water supply by well sampling data.
Therefore, it is unlikely that the slightly contaminated groundwater beneath the former
Unocal site would present a health risk to the public.
As mentioned previously, at a groundwater flow rate of 12 feet/year, it would take
approximately 20 years for site groundwater to reach the closest downgradient well (8&8
Leather well) located 240 feet away. Within this time frame, the groundwater plume is ,.
expected to be naturally degraded by intrinsic bioremediation (See Section 4.1 ). Based
on historical groundwater quality data, the remaining dissolved hydrocarbon plume is
confined to the Unocal site in the vicinity of MW-9, MW-10, MW-12 and RW-2 and has not
migrated beyond the "clean" peripheral monitor wells (MW-1, MW-2, RW-4, MW-13, MW-
14 and MW-15). In addition, dissolved gasoline compounds in groundwater are defined
vertically in the deep bedrock well MW-12.
Based on (a) a groundwater flow velocity range of 12 feet/year, (b) the distanc~ from on-
site monitor wells with groundwater 2L violations (MW-9, MW-10, MW-12 and RW-2) to
17
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
Intrinsic bioremediation parameters are interpreted by comparing the results from the
wells inside the plume with wells on the plume fringe and wells outside of the plume
(hydraulically upgradient and downgradient). At the Unocal-De~ta site, the February and
April 1996 groundwater anal~ical results revealed that only two wells (MW-9 and MW-1 0)
located in the initial plume area had any measurable dissolved hydrocarbons (44.7 ug/L .
and 83.2 ug/L MTBE, respectively).
Periphery wells (MW-3 and MW-10) and outside former plume wells (MW-6, MW-13, MW-
14 and MW-15) all display high dissolved oxygen and oxidative potentials. Along with no
BTEX, these results indicate that the periphery wells are clean and display similar
conditions as the background wells. Note: Fluctuations in the measured parameters are
insignificant. The intrinsic parameters are a qualitative indication and not quantitative.
Well, MW-9, in the middle of the previous plume, is under anaerobic conditions (low
oxygen, high negative potential, high Fe 2
+, and no nitrate). Lack of BTEX in this well may
indicate that the anaerobic condition is the result of the adsorbed phase BTEX reacting
with the (02 , NO 3
-, and Fe 3+) since there is no BTEX in the dissolved phase. Alternatively,
heavier than BTEX compounds (if present) may be causing the reactions that lead
anaerobic conditions. Since the dissolved phase BTEX is absent in MW-9, there is little ..
risk of BTEX migration.
Within the plume (MW-3, MW-9 and MW-10), intrinsic bioremediation parameters
demonstrate the following general patterns. Volatile organic concentrations are elevated
in proximity to the source or release area (tank pit area). Dissolved oxygen
concentrations are decreased due to the anaerobic state within the hydrocarbon plume
by the consumption of oxygen. Nitrate concentrations are lower due to the reducing
environment within the plume where denitrification reduces nitrate to nitrite. Sulfate
concentrations are also lower due to the reduction of sulfate to sulfite within the plume.
21
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NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
· June 13, 1996
6 COMPLIANCE WOULD PRODUCE FINANCIAL HARDSHIP ON UNOCAL
A total of approximately $751,863 has been spent to date by Unocal Corporation on
assessment and aggressive remediation of the subsurfac!:) hydrocarbons using best
available technologies. _ The state has determined the site to be ineligible for
reimbursement through the petroleum UST State Trust Fund. As you are aware Unocal
sold this site in 1987 and has not made any income on this site since then. It has been
a serious financial hardship to Unocal for the last 9 years. Unocal has remained in
compliance with state and county regulations during assessment and remediation
activities. Appendix 5 includes financial information of cost to date for project.
26
ATTACHMENT - V
IMPORTANT CORRESPONDENCE
State of North Carolina
Department of Environment
Health and Natural Resourc~s
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
.MA
DEHNR
September 5, 1997
MEMORANDUM
TO: Arthur Mouberry, P.E.
Chief, Groundwater Section
FROM: A. Preston Howard, Jr. P.0 pJ
z.
SUBJECT: Variance Request for the Former Unocal Facility at 29~ Gibbon Road in
Derita, North Carolina (GW Incident Number 3751).
I have reviewed the attached package submitted in support of a request for a variance
as outlined in 15A NCAC 2L .0113. Based on the information that has been submitted, I
have determined that sufficient information exists to concur that this variance should
proceed with public notice and hearing as outlined in the rules. Please provide public notice
in accordance with 15A NCAC 2L .0113( e) so that the Division can receive public input
prior to final action on this variance request.
cc: Groundwater Section Assistant Chiefs
David Hance
Mooresville Regional Hydrogeologic Supervisor
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Voice 919/733-32.21 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycied' 10% post-consumer paper
··.,·:
Received From:
S&ME-Charlotte
P.O. Box 7668
Charlotte,NC 28241
For: EPAG2!:i
Date Reported
Project Number
PO Number
FDHRSDW Number
FHRS ENVNumber
FDER COMQAPNum
LDHH Number
NCDEHNR Number
OCDIIX::C Humhe:,:
fLOWtVS
■ Ctil:M.ICA.L
I.A.OO~A TOlllfS -
INCORPORATED
Nov 4 1996
UNOCAFE835903292
1354-92-667
83139
E83018
86-0008G
94-23
296
!)(;01!)
uate sampled:Oct28 1996 Date ~eceived:Uct29 1996 Lab Number 12885
i REPORT OF ANALYSIS
12885
Parameter Unit NCPractical %ACC %PRC MW12
Quantitative
Limit
Isophorone ug/L 3.00 63.4 3.29 <3.00
N l L.i:·ul.Jt::n ;,;~111::: ug/L :) . 00 6!L5 :) .71 --..'.). 00
""······---.... , ...... , .... _, ··•·-··· ...... ,.., "\ nn ..... " n Acenaphthene ug/L 3.00 <3.00
Anthracene ug/L 3.00 <3.00
Benzo(a)anthracene ug/L 3.00 71.0 2.34 <3.00
Benzo(a)pyrene ug/L 3.00 <3.00
Benzo(b)fluoranthene ug/L 3.00 59.0 4.13 <3.00
Ri:>n7.() (a. h. ; ) pi:,ryl An&'" na/T. 1, () () ~fi fi A. R1 <1 ()()
U'01.1....__ (1· ... ) J::.J.. __ ,_..._ • ..,l,..l•-••--~,~"--' ~-00 .. ,.:, ., 0 0
Chrysene ug/L 3.00 81.2 3.88 <3.00
Dibnz(a,h)anthracene ug/L 3.00 <3.00
Fluoranthene ug/L 3.00 67.3 8 .31 <3.00
Fluorene ug/L 3.00 65.9 5.37 <3 .00
Indn(l,2,3-cd)pyrene ug/L 3.00 62.3 3.69 <3.00
Naphtha:j.ene ug/L 3.00 <3.00
1-methyl-Naphthalene ug/L 3.00 66.4 9.85 <3.00
2-methyl-Naphthalene ug/L 3.00 73.4 5.73 <3.00
Phenanthrene ug/L 3.00 67.4 .520 <3.00
Pyrene ug/L 3.00 92.5 1.11 <3.00
Intl_QA_Spike(2FBP) ug/L 3.00 69.6 .570 65.4
A -Rrmphn 1 _phnyl Ar.hAr \JQ' /T. '.LOO 74.4 1 . 0 () <~.00
& -:-1-i-a: 1--2-:,,,: 1---:..-:::L ...... 1_. --.M•':ic.. '!I,.~~ ":'Ir;'. r!"' I:" • 0 ,:\ .":). 0~
n("':' _, ... , ·--+-1 ... -.-}--... 1-.--••..::,-.. IT. "I nn , "I n n
B(2 chlri.:>pr:op)c:thc:r ug/L 3.00 -<3.00
b(2-chlorethyl)ether ug/L 3.00 62.1 5.29 <3.00
Data Release Authorization
Sample integrity and reliability certified by Lab personnel prior to analysis.
Methods of analysN· in accordance with FCL QA and EPA approved methodology.
This Report may not ep~~part, results relate only to items tested.
/\~ Jeffersco L Rowers, Ph.D . . st~°'\ C: ~,•f!:P .R~ ~erving Tour Ana1yucai ana t:nv1ronmema1 I\Jeeas wince I~~/ FAX; {4o·H feo=:;o
) Page 2 of 3
......
DIVISION OF WATER QUALITY
September 23, 1996
MEMORP..NDu""M TO: Arthur Mouberry
FROM: Allen Schiff i<__g
THROUGH:
SUBJECT:
Barbara Christian .If.__
Review of Variance Request for
Former Unocal Facility No. 9342-811
2932 Gibbon Road
Priority Rank 90/B
Mecklenburg County, N.C.
Groundwater Incident No. 3751
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Upon review of the June 1996 variance request, the
Groundwater Incident file for the subject site and Dr. Ken Rudo's
comments, the MRO offers the following:
1. The petroleum contaminant plume appears to be almost
completely remediated except for Benzene(3.34ppb) and l,2 -
dichloroethane(24.8ppb) found in deep(bedrock) monitor well
MW-12 per the most recent sampling conducted J8 29, 1996.
Additionally, bis(2-ethylhexyl)phthalate(hereinafter bis2) was
found i~ MW-12 at a concentration of 742ppb.
2. Air sparging and SVE were utilized at the site to remediate
the petroleum plume that contained BTEX as high as 31,l00ppb
(MW-14), prior to CAP implementation, to BDL in the same well as
of _the July 1996 sampling event.
3. Dr. Rudo indicates in his August 12, 19 9.6, memo that he
cannot suppqrt the variance request due to the high level of bis2
found in MW_;l2. His rec·ommendation is further remediation of the
bis2 constituent. I orrer the following items for consideration
with respect to Dr. Rudo's comments and Unocals options:
A. The existing air sparging/SVE system could not be utilized
to remediate the bis2 in MW-12 because it is a bedrock
well where uncontrolled sparging is not advisable. This
would require Unocal to implement a separate CAP system to
remediate the bis2.
B. Unocal has expended in excess of $751,863 at the site
that has previously been determined to not be reimbursable
from the STF. In addition, O&M costs for the existing
CAP system would total approximately $20,000 annually when
the system was in operation.
C. Since bis2 is not related to petroleum contamination, it
may have been introduced to MW-12 throucrh the remediation
system. This statement can be supportea by the following~
1. The remediation system utilized vacuum pumps and bis2 --
is a liquid used in vacuum pumps(see attached).
2. In the 11/3/94 sampling of MW-12, tis2 was found at
only Sppb but jumped to 2700ppb during an August 18,
1995 sarnRling. During this time period Unocal
utilized a separate consulting firm than S&ME to
perform O&M on the CAP system components. This
consulting firm was terminated by Unocal for
poor contract performance in part due to no maintenance
on the coaliscing filters for the sparging unit.
The MRO has requested additional information from
Unocal about the circumstances leading to the dismissal
of the consultant. The current level of bis2 was 742ppb
as of the July 29, 1996 sampling.
In light of Dr. Rudo's comments, the level of bis2 in
bedrock monitor well MW-12 and active water supply wells in the
area, the MRO finds that, at this time, a CAP in accordance with
lSA NCJ._C 2L . 0106 (kl, (1) and/or (m) does not appear to be an
option at the Unocal site. If the source of the bis2 could be
confirmed to have been introduced to MW-12 by the existing CAP
system, as indicated on page six of the variance request, then
the appropriate action would have to be taken. If on the other
hand it is determined that the bis2 is from a~·offsite source,
then the variance could be approved based upon the contamination
that Unocal was .responsible for.
If you should have any questions, I can be reached at (704)
66j-1699 ext. 236.
J,_ttachmen_t_s
ajs
EMC GROUNDWATER COMMITTEE AGENDA ITEM# 2
has been expended to remove tanks, conduct site assessments, and cleanup soils this site.
All these costs associated with Groundwater Incident # 3 7 51 have been incurred by the
Unocal Corporation. It has been estimated that continued operation of air sparging with
soil vapor extraction at this site will cost approximately $ 20,000 per year. The Unocal
Corporation does not believe that there are alternate technologies that will remediate the
site any more effectively than those used over the past few years.
Since cleanup was implemented on June 16, 1993, concentrations of substances
have been significantly reduced by groundwater cleanup technologies located at the site.
Since August 1995 analysis of samples from monitoring wells showed only marginal
reductions in the concentration of substances in groundwater. Analysis of groundwater
samples taken on December 1, 1995 and on February 25, 1996 showed there was no
significant increase or decrease in concentrations of Benzene and other substances at the
off-site monitoring wells, while cleanup operations were being conducted. Based on
groundwater analysis of samples from semi-annual monitoring from 1992 through 1995,
the Division of Water Quality recommended that air sparging and soil vapor extraction
technologies be turned off to determine if residual contaminants in the soils and
subsurface would recontaminate the groundwater, if no treatment system were operating.
Upward "rebounding" of concentrations above the Groundwater Quality Standards in
15A NCAC 2L .0202 has been noted for some of these monitoring wells. With the
exception of two on-site monitoring wells, the groundwater analysis on July 29, 1996 has
shown that concentrations of substances in monitoring wells have been reduced below
detectable limits. Substances in the two on-site wells near the area where the release
occurred remain slightly above the Groundwater Quality Standards in 15A NCAC 2L
.0202.
The Unocal Corporation does not believe that a variance at this site will
endanger public health, safety or the environment. There are forty-two ( 42) water supply
wells serving residences and businesses within ½ mile of the site. Most of these
properties are served by public water from the City of Charlotte. Of the five wells
located near the site, four of them are not being used for drinking water supply. The well
nearest to 2932 Gibbon Road, and the one that is currently used for water supply, is
located at 6810 Nevin Road and is identified in the variance request as "B&B Leather".
The well has been continually sampled since April 1993 and substances have never been
reported in this well. The Unocal Corporation asserts that remaining substances in the
contaminant plume exceeding the 15A NCAC 2L .0202 Groundwater Quality Standards,
such as Benzene, would not reach the closest receptor B&B Leather Company for 22
years. This estimated range assumes no dilution or attenuation of the plume occurs. The
company has submitted information showing that conditions at the site are such that
substances in the groundwater will likely biodegrade due to the presence of indigenous
microorganisms in the subsurface. The company asserts that these natural conditions are
such that the entire plume of substances is expected to degrade to the extent that
concentrations will be below the Groundwater Quality Standards in 15A NCAC 2L. 0202
before the plume reaches this cross-gradient water well. The company has submitted
information showing that no water supply intakes or water supply lines will be impacted
if a variance is granted at this site. The nearest surface water body, Erwin Creek, is
approximately I, I 00 feet away and has not been impacted by substances at this site.
On September 23, 1996 the Mooresville Regional Office recommended that this
variance be granted. On February 7, 1997 the Division of Epidemiology concurred with
the recommendation of the regional office. On September 5, 1997 the Director of the
Division of Water Quality gave approval for this variance to proceed to public notice and
hearing pursuant to the requirements contained in ISA NCAC 2L .0113.
-ii-
EMC GROUNDWATER COMMITTEE AGENDA ITEM# 2
Pursuant to ISA NCAC 2L .0113(d) and (e), public notice of this variance was
sent to adjacent property owners, forty-two well owners, the Mecklenburg County Health
Director, the City Manager for the City of Charlotte, and the Mayor of Charlotte on
October 16, 1997. Notice of this hearing was also published in the October 18, 1997
edition of the Charlotte Observer to meet requirements of 15A NCAC 2L .0113( e )( I )(A).
In addition, approximately 15 8 notices of this variance request were sent to persons listed
in the "Groundwater Variance and Regulatory Actions Mailing List" to meet the
requirements of ISA NCAC 2L .0113(e)(l)(F).
fl 1
A public hearing was held on November 18, 1997 in Statesville, North Carolina.
This hearing was attended by one individual from S & ME Incorporated, representing
the Unocal Corporation. No other persons that attended this hearing and no comments
were made at the hearing. Only one written comment was received prior to December
19, 1997 from the Assistant Regional Engineer in the Public Water Supply Section
expressing no objection to granting this variance.
RECOMMENDATION:
It is recommended that the Environmental Management Commission
Groundwater Committee send the request for variance for the Unocal Corporation
site at 2932 Gibbon Road in Charlotte, North Carolina (Groundwater Incident
Number # 3 7 51) to the Environmental Management Commission on March 12,
1998 with a request that this variance be granted pursuant to the requirements of
15A NCAC 2L .0113 and North Carolina General Statute 143-215.3(e). Itis also
recommended that this variance be approved without the requirement for the
Unocal Corporation to conduct monitoring based on information in the variance
request demonstrating the effectiveness of remediation efforts, the cost incurred
by the company, the results of monitoring showing no significant increase in
substances at this site when cleanup operations were suspended, the comment
received and interest level from the public who were provided advanced notice of
,.,i,.::...ID-: __ , __ LR'~!!,_~... , ; , _ the public hearing, and the lack of impact the site has on water supply wells.
:.ii . t . ·, ,,.,. l.·'it'"'··~"T ... "-~ ~-----~--_ ; _-_, , __ :w:\-~_:~~ ,.y-··~~ .~--, r~ ,$~~ ~;"· ~, .
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-iii-
Author: David Hance at NRGWS0lP
Date: 1/30/1998 2:40 PM
Priority: Urgent
Receipt Requested
TO: [e-mail] at Internet
CC: David Hance
CC: Carl Bailey
CC: Arthur Mouberry
Subject: RE: VARIANCE-HEARING OFFICER'S REPORT
------------------------------------Message Contents------------------------------------
***** URGENT !/HEARING OFFICER'S REPORT/ VARIANCE/ UNOCAL -DERITA***
######################################################################
HI TOMMY,
I HAVE GOT YOUR REPORT -LOOKS GREAT! WHEN I LOOKED AT THE
ATTACHMENTS I NOTICED THERE WERE NO "DIVIDERS" BETWEEN THEM SHOWING
WHAT THEY ARE. YOU MENTIONED 4 ATTACHMENTS IN YOUR REPORT. IT IS
IMPORTANT TO NOTE THAT ..... THE HEARING OFFICERS REPORT WILL GO TO
PRESTON HOWARD FOR APPROVAL AND ... I SAID .... AND ... THE REPORT
AND ATTACHMENTS WILL GO TO ....... THE ELEVEN EMC GROUNDWATER
COMMITTEE MEMBERS FOR THE FEBRUARY 11TH MEETING.
IN ORDER TO MAKE IT EASY FOR NON-TECHNICAL PEOPLE TO FOLLOW THIS, I
INSERTED TITLE PAGES WHERE YOU SAY ATTACHMENTS GO IN YOUR REPORT.
THESE ATTACHMENT COVER PAGES ARE IN THE FILES SHOWN THAT I HAVE
APPENDED TO THIS E-MAIL MESSAGE. THEY ARE IN WORDPERFECT 5.1.
FOR ATTACHMENT FOUR (OR ATTACHMENT IV) WE CAN'T SEND THE ENTIRE
1 INCH THICK VARIANCE OUT TO THE COMMITTEE MEMBERS WITH MAPS, CHARTS
AND TABLES ..... OVERKILL! ---THAT WOULD BE A LOT OF COPING AND THE
COMMITTEE WOULD NOT LIKELY HAVE TIME TO READ IT ANYWAY. I HAVE
SPECIFICALLY STATED ON THIS COVER PAGE THAT THIS ATTACHMENT INCLUDES
THE MEMO & EXECUTIVE SUMMARY REPORT FROM UNOCAL ON IT.
IN ADDITION .... IN ADDITION, I ALSO ADDED .... AN ...... .
ATTACHMENT FIVE (ATTACHMENT V) .... WHICH INCLUDES MEMORANDUM FROM .THE
MRO STAFF ENDORSING THE VARIANCE, THE ISSUE WITH THE CHEMICAL RAISED
BY DR. RUDO WITH THE DIVISION OF EPIDEMOLOGY AND HIS LATER CONCURRENCE
WITH THE VARIANCE, AND PRESTON'S APPROVAL TO GO TO HEARING.
I THINK ALL OF THIS WILL BE SUFFICIENT TO ANSWER ANY QUESTIONS THEY
HAVE.
IF ALL OF THIS IS FINE WITH YOU ..... REPLY BACK TO ME WITH AN E-MAIL.
IF WE NEED FURTHER DISCUSSION OR CHANGES PLEASE CALL 919-715-6189
OR E-MAIL BACK A RESPONSE .
HAVE A NICE FRIDAY,
DAVID HANCE
Author: David Hance at NRGWS0lP
Date: 1/29/1998 2:47 PM
Priority: Urgent
Receipt Requested
TO: [e-mail] at Internet
CC: Carl Bailey
CC: Arthur Mouberry
CC: David Hance
Subject: My Suggestions/Hearing Officer's Report/ Unocal Derita
------------------------------------Message Contents------------------------------------
*** IMPORTANT/ CHANGES TO HEARING OFFICER'S REPORT/ UNOCAL DERITA/**
DEAR TOMMY,
Here are some changes I would suggest to the draft hearing
officer's report you just faxed me:
(1)
II
(2)
II
(3)
(4)
On the first page under PUBLIC HEARING 3rd line down ...
we sent a copy of the notice
to approximately 200 people including 42 well owners
First, second paragraph, second line -It should read
S& ME Incorporated."
II
On Page# 2 of the report you say that
bis(2-ethylhexyl)phthalate does not have a groundwater
standard. This substance does have a Groundwater Quality
Standard in 15A NCAC 2L .0202(g) (32). It is DEHP and the
number is 0.003 milligrams/liter or 3 micrograms per liter.
Since you have the variance in Fayetteville, you may want
to look at the most recent data for the concentration of
this substance.
Page 2 ... We said on the first page that there were 42
well owners but here is says 48 well owners. Is this a
typo? Which number is correct?
These are all the recommended changes that I see in the copy you
faxed me. Please note that the EMC Groundwater Committee will meet on
February 11, 1998. I plan to mail out your report to the Committee
with the rest of the meeting materials on Wednesday February 4, 1998
(hopefully). Between now and then Arthur and Preston will need to sign
off on this.
Once you have all the changes in this report that satisfy you, I
would be glad to see to it that it goes to the Director and the
Commission. If you can send this to me FEDERAL EXPRESS .......... .
"NEXT BUSINESS MORNING", I am certain we can get it approved in time
for mailing.
If all goes well at the February 1998 EMC Groundwater Committee
meeting, the full EMC will rule on this variance in March 1998. Once
they approve I will prepare a letter informing the responsible party
of this.
If we need further discussion call me at 919-715-6189 or e-mail me.
HAVE A NICE DAY,
DAVID HANCE
Author: David Hance at NRGWS0lP
Date: 1/22/1998 10:57 AM
Priority: Urgent
TO: [e-mail] at Internet
CC: David Hance
Subject: RE: HEARING OFFICER' S REPORT AND RECOMMENDATION ON VARIANCE
------------------------------------Message Contents------------------------------------
*******IMPORTANT/TIME SENSITIVE/ UPDATE NEEDED/ VARIANCE *****
HI TOMMY,
HOW IS IT COMING ALONG WITH THE HEARING OFFICERS REPORT AND
RECOMMENDATION FOR UNOCAL DERITA VARIANCE?
WE HAVE SCHEDULED THIS TO GO BEFORE THE EMC GROUNDWATER COMMITTEE
ON WEDNESDAY FEBRUARY 11, 1998.
BUT ..... MY MAILING DATE TO GET THIS REPORT IN THE GROUNDWATER
COMMITTEE PACKET IS FEBRUARY 4, 1998.
AND ..... PRESTON WILL NEED TO GET IT BEFORE FEBRUARY 4TH SO HE CAN
APPROVE OF IT.
PLEASE CALL ME OR E-MAIL ME IF WE NEED TO TALK FURTHER.
DO YOU HAVE ANY QUESTION FOR ME? I WOULD BE GLAD TO HELP OUT.
DAVID HANCE
OCF-5
11/20/95
Division: 1) vJ q
Vendor Number:
Vendor Name:
Vendor Address:
Remit Code/Message:
Page __ of __
CASH DISBURSEMENTS CODE SHEET
Shaded fields (i.e., Terms Code, SAS Item No., & 1099 Code) will be completed by the Controller's .Offlce
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L=============!::::::::====:::::::::!!:=:::!:~ ----------------------
Prepared By: e.A-Date: I \ -'1-4,-(
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Please use yello~. ,.,Jper.
Author: David Hance at NRGWS0lP
Date: 1/14/1998 3:02 PM
Priority: Normal
TO: [e-mail] at Internet
CC: David Hance
Subject: re: UPDATE -THE UNOCAL VARIANCE
------------------------------------Message Contents------------------------------------
HI TOMMY,
HOW IS THE HEARING OFFICER'S REPORT AND RECOMMENDATION COMMING
ALONG FOR THE VARIANCE (UNOCAL/ DERITA) ? DO YOU NEED ANYTHING FROM
ME?
PLEASE E-MAIL A RESPONSE OR CALL 919-715-6189.
DAVID HANCE
Author: "Tommy Stevens DEM" <[e-mail] .state.nc .us> at Internet
Date: 12/30/1997 4:27 PM
Priority: Normal
Receipt Requested
TO: David Hance at NRGWS0lP
Subject: re: variance for UNOCAL -DERITA in Charlotte, NC
------------------------------------Message Contents------------------------------------
I have not received any comments on the variance.
I will look back over the material again, but it seems
rather straight forward to me to recommend that the
variance be granted.
Author: David Hance at NRGWS01P
t Date: 12/30/1997 4:17 PM
Priority: Urgent
TO: [e-mail] at Internet
CC: David Hance
Subject: re: variance for UNOCAL -DERITA in Charlotte, NC
------------------------------------Message Contents------~-----------------------------
TOMMY,
THE DEADLINE FOR THE PUBLIC TO PROVIDE COMMENT ON THE UNOCAL DERITA
VARIANCE WAS DECEMBER 19, 1997.
I HAVE RECEIVED ONE COMMENT FROM BRITT SELTZER FROM THE PUBLIC WATER
SUPPLY SECTION IN MOORESVILLE ON THIS VARIANCE . THEY HAVE NO
OBJECTION TO THIS.
I HAVE NOT RECEIVED ANY MORE COMMENTS .... HAVE YOU?
***> I WILL MAIL A COPY OF THE COMMENT I GOT FROM BRITT VIA THE STATE
COURIER SERVICE. < ***
IF YOU HAVE NOT ALREADY BEGUN THE EXAMINATION FOR THE VARIANCE
MATERIALS THAT YOU HAVE YOU MAY DO SO NOW.
PER YOUR NOVEMBER 7, 1997 MEMO .... THE DIRECTOR WANTS A HEARING
OFFICER'S RECOMMENDATION AND BY MARCH 19, 1998 .
IF YOU NEED TO DISCUSS THIS WITH ME .... PLEASE CALL OR EMAIL A
RESPONSE .
DH
Author: "Setzer; Britt" <[e-mail] .nc.us> at Internet
Date: 11/20/1997 10:47 AM
Priority: Normal
CC: Wayne Munden at NROHW0lP
TO: David Hance at NRGWS0lP
CC: [e-mail] at Internet
Subject: Groundwater Incident #3751 -Unocal Corporation -Variance
------------------------------------Message Contents------------------------------------
David,
The Mooresville Regional Office Public Water Supply Section has
investigated the requested groundwater variance area. As noted on the
Notice of Variance Application and Hearing, this area is inside the
city limits of Charlotte. The majority of the Gibbon Road and Nevins
Road area is served by Charlotte Mecklenburg Utility Department water
lines. Therefore, we have no objection to the variance being granted
since city water is available in this area.
Britt Setzer
Assistant Regional Engineer
Public Water Supply Section
1
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TABLE OF CONTENTS
INTRODUCTION
1. 1 Reports Submitted to State
1.2 Permits Issued by the State or County
1.3 Recent State Correspondence Concerning Remediation System
1.4 Groundwater Sampling Event of April 24, 1996
1.5 Historical Groundwater Quality Data
DESCRIPTION OF PAST, EXISTING OR PROPOSED ACTIVITIES
2.1 Site Location, Ownership
2.2 Past Activities
2.2.1 Soil Vapor Extraction System
2.2.2 Air Sparging System
2.3 Existing Activities
2.4 Proposed Activities
3 DESCRIPTION OF THE PROPOSED VARIANCE AREA
4
5
6
7
8
9
3.1 Potential for Groundwater Migration
VARIANCE WILL NOT ENDANGER THE PUBLIC HEAL TH AND SAFETY
4.1 Measured Intrinsic Bioremediation in On-site Groundwater
EVALUATION OF FURTHER REMEDIAL ALTERNATIVES
COMPLIANCE WOULD PRODUCE SERIOUS FINANCIAL HARDSHIP ON
UNOCAL
COMPLIANCE WOULD PRODUCE SERIOUS FINANCIAL HARDSHIP WITHOUT
EQUAL OR GREATER PUBLIC BENEFIT
NO SPECIAL ORDER OF CONSENT WAS ISSUED BY STATE
LIST OF ADJACENT PROPERTY OWNERS, ADDRESSES & PARCEL #s
•
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
1 INTRODUCTION
1. 1 Reports Submitted to State
S&ME Project No. 1354-92-667
June 13, 1996
The following reports have been prepared for the site and submitted to the Groundwater
Section of the North Carolina Department of Environment, Health and Natural Resources
(NCDEHNA), Mooresville Regional Office: (1) A Tank Closure Report Dated October
1991, (2) A Comprehensive Site Assessment Dated June 2, 1992, (3) A Corrective Action
Plan Dated December 23, 1992, and (4) numerous quarterly air quality reports and semi-
annual groundwate_r quality reports submitted since 1992.
1.2 Permits Issued by the State or County
No permits were issued to this site by the State, except for monitor well installation.
Permits were not required by the State for construction and operation of the SVE and AS
remediation systems. The vacuum for the SVE system was registered with the state as
an air emission source. An air qt:Jality permit No. 93-027-855 was issued to Unocal
Corporation (Unocal) on March 24, 1993 and voided on October 17, 1994 due to the
deactivation and proposed removal of the SVE system and the de minimis uncontrolled
emissions of volatile organic compounds from the groundwater remediation activity.
1.3 Recent State Correspondence Concerning Remediation System
The most recent correspondence from the NCDEHNR-Mooresville Regional Office (MAO)
relative to our February 16, "1996 Request For Site Closure was dated April 1, 1996, and
stated that "At this time Unocal could request a variance or propose a risk based CAP in
accordance with 15A NCAC 2L .0106 (k,I or m) but a site closure is at this time not a
viable option." A "clean" closure is inappropriate due to: (a) the site conditions do not
meet the closure· requirements specified in the March 1993 "Groundwater Section
Guidelines For The Investigation and Remediation of Soils and Groundwater", and (b)
slight exceedances of the 2L groundwater standards at MW-6, MW-9, MW-10, MW-12 and
RW-2. The April 1, 1996 letter also suggested sampling groundwater from monitor wells
4
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
converted to either vacuum or air sparging wells (MW-3, RW-1 and RW-2) for additional
water quality data.
1.4 Groundwater Sampling Event of April 24, 1996
S&ME sampled groundwater from MW-3, MW-10, RW-1, RW-2 and RW-4 for Method 601,
602 extended and 504.1 analyses on April 24, 1996. Groundwater from former
vacuum/sparge well RW-3 was not sampled, since groundwater from adjacent monitor
well MW-2 has always been "clean". This groundwater sampling event was performed in
response to the State's April 1, 1996 letter and to update groundwater quality data, as
part of this Variance Request. Groundwater levels were measured prior to sampling on
April 24, 1996 (Table 2). The groundwater samples were analyzed by Flowers Chemical
Laboratories, Inc. of Altamonte Springs, Fl (NC Certification #296). The laboratory results
are included in Appendix 1.
The April 24, 1996 analytical results revealed no measurable dissolved hydrocarbons in
groundwater from RW-2, RW-4 and MW-3. MTBE was only detected in MW-1 0 (83.2
ug/L) and RW-1 (24.1 ug/L).
1.5 Historical Groundwater Quality Data
Historical groundwater quality data indicates that the dissolved hydrocarbon plume has
decreased progressively in size and severity. Appendix 2 includes all benzene, toluene,
ethylbenzene, and total xylene (BTEX) plume isoconcentration maps to date for the site,
which illustrate initial plume configuration before remediation and after remediation. Figure
7 also illustrates the BTEX concentration map for groundwater on February 25 and 26,
1996. The February, 1996 sc1mpling event was the last semi-annual groundwater
sampling event of all wells for Class I hydrocarbon parameters, as required by the State.
Groundwater sampling for Class II hydrocarbons is performed in August, 1995 as required
by the State. The February 1996 laboratory results indicate that all Class I and II
5
·-]··
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
hydrocarbon compounds were below 2L groundwater standards, except as follows: off-
site monitor ~ell MW-6 [6.43 ug/L of Bis(2-ethylhexyl)phthalate J, and on-site monitor wells
MW-9 [2.02 ug/L of isopropylether (IPE) and 3.6 ug/L of 1,2-dichloroethane (1,2-DCA)],
MW-12 [578 ug/L of bis(2-ethylhexyl)phthalate], and RW-2 [4.55 ug/L of 1-methyl-
naphthalene, 2.69 ug/L of 2-methyl-naphthalene, and 4.08 ug/L of bis(2-
ethylhexyl)phthalate].
The 2L groundwater violations at MW-6 may be from a new non-gasoline release at the
Handry Pantry or nearby, as this well has been free of dissolved gasoline type
hydrocarbons from March 4, 1993 through February 25, 1996, as indicated in Table 1.
The methylene chloride and bis(2-ethylhexyl)phthalate detected in groundwater from MW-
6 are believed to be unrelated to the Unocal gasoline release of 1987. No hydrocarbon
release has been recorded by the NCDEHNR-Mooresville or Raleigh Offices for the
Handry Pantry store #72 at 2947 Gibbon Road, Derita, NC. In addition, the bis(2-
ethylhexyl)phthalate detected in deep (Type Ill) monitor well MW-12 may be from an off-
site source and is believed to be unrelated to the Unocal gasoline release of 1987. Bis(2-
ethylhexyl)phthalate is a plasticizer and may be from sampling equipment (i.e. latex gloves
or polyethylene bailers). Another possible source of the bis(2-ethylhexyl)phthalate is from
dissolved plastic or a-rings inside the oil coalescing filters and other sparge controls.
] The low levels of dissolved hydrocarbons [i.e. benzene (0.784 ug/L), MTBE (83.2 ug/L),
IPE (2.02 ug/L), 1,2-DCA (3.6 ug/L), bis(2-ethylhexyl)phthalate (578 ug/L), naphthalene
(1.22 ug/L), 1-methyl-naphthalene (4.55 ug/L), and 2-methyl-naphthalene (2.69 ug/L)]
in groundwater are confined to the former Unocal site and do not appear to be migrating,
as evidenced by the "clean" peripheral wells MW-1, MW-2, RW-4, MW-13, MW-14 and
MW-15. Dissolved gasoline compounds in groundwater are defined vertically in the deep
bedrock well MW-12.
6
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NCDEHNR-Groundwater Section Unocal Derita-Variance Request S&ME Project No. 1354-92-667
June 13, 1996
The following information supports the State requirements for a variance request, as
specified in 15A NCAC 2L.0113(c):
2 DESCRIPTION OF PAST, EXISTING OR PROPOSED ACTIVITIES
2. 1 Site Location, Ownership
The site location is shown in Figure 1 on a 1972 USGS Derita, NC Map. The site was
formerly owned and operated by Unocal as a service station until 1987. The property
was sold to Frank Dwyer in 1987 and is presently operated as Dwyers Auto Repair. The
topography on site slopes to the east, as indicated in Figure 3.
2. 2 Past Activities
Unocal operated the property as a service station until 1987. The property was sold by
Unocal to Frank Dwyer in 1987. As a condition of the sale of the property, tank tightness
testing was performed in 1987 on the existing UST systems. One of the gasoline tanks
failed tightness testing, and a release was suspected. This was confirmed in a preliminary
assessment report submitted to the state on January 14, 1988. Seven underground
storage tank (UST) systems consisting of the following: four 4000-gallon gasoline, one
2000-gallon diesel, one 550-gallon waste oil, one 550-gallon kerosene steel tanks and all
piping and dispensers were removed in 1987. The USTs were used for commercial
purposes.
During tank removal, 2300 tons of gasoline contaminated soil were removed and treated
on-site using passive bioremediation. The passive bioremediation was unsuccessful in
reducing soil TPH levels to below 10 ppm. Therefore, the soils were later transported to
Cunningham Brick Co. for thermal destruction. The majority of gasoline containing soils
were excavated from the site during the tank removal. The remaining contaminated soils
were remediated by soil vapor extraction and air sparging.
7
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NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
Air sparging initially volatilized the dissolved and adsorbed hydrocarbons in the phreatic
~ zone. After most of the volatilization had occurred, bioremediation became more
dominant in groundwater remediation due to the increase in dissolved oxygen from
...
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sparging. Gasoline degrader bacterial populations increased after sparging was initiated
and decreased with time as hydrocarbons (food source) were removed by volatilization
and consumption.
Dissolved hydrocarbons have also been reduced considerably by air sparging, as
indicated by the non-detect levels in the vacuum inlet air stream and the reduction of
dissolved hydrocarbons in the groundwater to below method detection limits and 2L
standards for BTEX. Therefore, we believe that the limits of remediation by best available
technologies (SVE and AS) have been achieved as economically and technologically
feasible.
Charts 2 through 9 illustrate BTEX, MTBE, and EPA Methods 601 and 625 compound
concentrations in groundwater with time: Chart 2 illustrates BTEX concentrations in
groundwater from wells initially exhibiting the greatest dissolved hydrocarbon
concentrations (i.e. inner plume wells). BTEX concentrations at MW-9, MW-10, MW-12
and MW-14 decreased from > 10,000 ug/L to < 1 ug/L during the 18 months of air
sparging and 14 months of soil vapor extraction. Chart 3 illustrates BTEX concentrations
in groundwater from wells initially exhibiting low dissolved hydrocarbon concentrations (i.e.
peripheral monitor wells). BTEX concentrations at MW-1, MW-2, MW-6, MW-11, MW-13,
MW-15, RW-3, and RW-4 decreased from >100 ug/L to <1 ug/L in the 18 months of
remediation. All BTEX concentrations in wells on-site and off-site are currently
below 1 ug/L. Chart 4 illustrates MTBE concentrations in groundwater from wells
-J exhibiting greatest dissolved hydrocarbon concentrations. MTBE concentrations at MW-3,
MW-9, MW-10, MW-12, MW-14 and RW-2 decreased from > 10000 ug/L to < 100 ug/L
as a result of remediation. Chart 5 illustrates MTBE concentrations in groundwater from
10
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• NCDEHNR-Groundwater Section Unocal Derita-Variance Request S&ME Project No. 1354-92-667
June 13, 1996
3 DESCRIPTION OF THE PROPOSED VARIANCE AREA
The area covered by the variance request includes the entire Dwyer Auto Repair (former
Unocal) property boundary, as illustrated in Figure 2. The two nearest cross roads are
Nevin Road and Gibbon Road. Figure 2 also illustrates all on-site and off-site monitor
wells and the existing remediation system layout. Figure 3 is a City of Charlotte
Topographic map (4 pages) of the Unocal site and surrounding area. Figure 4 is a
Mecklenburg County Tax Map of the site with adjacent property owners (name, address
and tax parcel #). the direction of the adjacent properties relative to the Unocal site can
be interpreted from the map.
There are no adjacent properties with any reported sources of groundwater contamination
or on-going remediation, according to the NCDEHNR-Mooresville and Raleigh offices.
Figure 5 is a VISTA map of environmental risk sites within one mile of the site. A small
quantity generator is located approximately 0.25-mile from the site. No groundwater or
soil contamination or remediation is reported for this facility. A leaking underground
storage tank (LUST) site was identified along W. Sugar Creek Road approximately 0.5-
mile from the former Unocal site. Both of these two sites are believed to be too distant
to impact the former Unocal site. The low levels of tetrachloroethene in the former
Gamble Pallet Co. well and low levels of methylene chloride and bis(2-ethylhexyl)phthalate
in off-site monitor well MW-6 may indicate off-site sources of groundwater contamination.
3.1 Potential for Groundwater Migration
The dominant mechanism of groundwater migration is advection or the natural flow of
groundwater under gravity or hydraulic gradient. Figure 7 illustrates that natural
groundwater flow was predominantly towards the south-southeast under a hydraulic
gradient of 0.01 on November 30, 1995. Generally the groundwater flow follows the slope
of topography. Previous groundwater flow maps indicate groundwater flow to fluctuate
14
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•
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
2-met-naph - 2 .69 ug/L @ RW-2
2-met-naph -2 .69 ug/L a RW-2
2-met-naph • 2 .69 ug/L @ RW-2
Note:
1-met-naph = 1 methyl-naphthalene
2-met-naph = 2-methyl-naphthalene
8is{2-e)-phth = 8is(2-ethylhexyl)phthalate
425 feet to Inactive Delta Unit Rebuilders Well (WSW-5)
475 feet to Inactive Gamble Pallet Co. Well (GPW-1)
1075 feet to Closest Suriace Water Body (Unnamed Creek)
19
35 years
40 years
90 years
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
Intrinsic bioremediation parameters are interpreted by comparing the results from the
wells inside the plume with wells on the plume fringe and wells outside of the plume
(hydraulically upgradient and downgradient). At the Unocal-Derita site, the February and
April 1996 groundwater analytical results revealed that only two wells (MW-9 and MW-1 0)
located in the initial plume area had any measurable dissolved hydrocarbons (44.7 ug/L
and 83.2 ug/L MTBE, respectively).
Periphery wells (MW-3 and MW-10) and outside former plume wells (MW-6, MW-13, MW-
14 and MW-15) all display high dissolved oxygen and oxidative potentials. Along with no
BTEX, these results indicate that the periphery wells are clean and display similar
conditions as the background wells. Note: Fluctuations in the measured parameters are
insignificant. The intrinsic parameters are a qualitative indication and not quantitative.
Well, MW-9, in the middle of the previous plume, is under anaerobic conditions (low
oxygen, high negative potential, high Fe 2+, and no nitrate). Lack of BTEX in this well may
indicate that the anaerobic condition is the result of the adsorbed phase BTEX reacting
with the (02 , NO 3 ·, and Fe 3+) since there is no BTEX in the dissolved phase. Alternatively,
heavier than BTEX compounds (if present) may be causing the reactions that lead
anaerobic conditions. Since the dissolved phase BTEX is absent in MW-9, there is ·1ittle
risk of BTEX migration.
Within the plume (MW-3, MW-9 and MW-10), intrinsic bioremediation parameters
demonstrate the following general patterns. Volatile organic concentrations are elevated
in proximity to the source or release area (tank pit area). Dissolved oxygen
concentrations are decreased due to the anaerobic state within the hydrocarbon plume
by the consumption of oxygen. Nitrate concentrations are lower due to the reducing
environment within the plume where denitrification reduces nitrate to nitrite. Sulfate
concentrations are also lower due to the reduction of sulfate to sulfite within the plume.
21
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
Ferrous iron concentrations are elevated due to the reducing environment where ferric
iron (Fe 3 +) gains an electron to become ferrous iron (Fe 2+).
ORP or oxidation-reduction potential is a measure of electron activity and is typically
biologically mediated. Under oxidizing conditions the ORP is higher (i.e. positive) than
under reducing conditions (inside the plume), where the OAP may be negative. PH
measurements effect the presence and activity of microbial populations in groundwater.
Microbes capable of degrading petroleum hydrocarbon compounds generally prefer pH
values varying from 6 to 8. Conductivity increases as ionic concentrations increase and
thus conductivity can vary between contaminated and uncontaminated groundwater. An
increase in alkalinity across a contaminant plume is potentially an indicator of bioactivity.
Temperature directly affects the solubility of oxygen and other geochemical parameters,
although temperature is typically not an indicator parameter of biological activity.
The historical water quality data and the intrinsic bioremediation parameters measured at
the Unocal-Derita site demonstrate that the plume is indeed reducing in size and severity
and that intrinsic bioremediation is occurring. Intrinsic bioremediation parameters at
center of plume well, near MW-9, indicate a reducing or anaerobic environment, typical
of groundwater in the center of plume, with exception to the elevated sulfate
concentration. Groundwater parameters at MW-9 (center of the plume) indicate the
following: Lowest DO reading on-site, highest ferrous iron concentration, lowest OAP,
and lowest nitrate concentration indicate a reducing state; alkalinity is highest indicating
biological activity; conductivity is high at MW-9 further indicating good ionic activity; and
pH is within the 6-8 range to support biological activity. Temperature does not appear
to be a biodegradation indicator.
In the peripheral plume wells (MW-3 and MW-10) these parameters are less correlative.
These wells are believed to be in transition, and thus show both reducing and oxidation
22
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NCDEHNA-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
qualities. These wells previously contained BED< due to their close proximity to the
former tank pit. However, there is still some contrast between these wells, th~ center of
plume well, and the wells outside the former plume extent. Signs of a reducing
environment are exhibited in groundwater from MW-3 in that conductivity and alkalinity are
higher than other wells outside of the plume. Nitrate at MW-3 is lower than most wells.
Groundwater from MW-10 shows highest conductivity, relatively elevated alkalinity,
relatively low OAP and low sulfate. Signs of an oxidation environment are also exhibited
in groundwater from MW-3 in that ferrous iron is low, OAP is high and sulfate is low.
Groundwater from MW-10 shows oxidizing parameters in that ferrous iron is low, and
nitrate is high.
In the outermost "clean" or background wells, signs of an oxidation environment (losing
of electrons) are evrdent at MW-6, MW-13, MW-14 and MW-15. Groundwater parameters
in these wells show higher DO levels, lower Fe 2+, comparatively lower conductivities and
alkalinities, higher nitrate levels except at MW-13, comparatively higher sulfate levels
except at MW-6, and higher ORP levels.
23
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NCDEH NA-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
5 EVALUATION OF FURTHER REMEDIAL ALTERNATIVES
Groundwater pump and treatment technology provides effective treatment when dissolved
contaminant concentrations are high and the groundwater plume is relatively small, such
that there is not a great distance for the contaminant to travel back to the recovery well.
Pump and treat is most useful for controlling plume migration when other technologies
are not effective or feasible. However, as concentrations of dissolved hydrocarbons
decrease to near asymptotic levels, such as now exist at the Unocal-Derita site, the·
benefits of further r~mediation decrease. This technology by itself, will not likely reduce
the existing contaminant levels below the 2L groundwater standards within a reasonable
time frame. S&ME considered several alternatives that may decrease the remaining
dissolved hydrocarbon levels.
One technology considered was enhanced bioremediation. This method involves the
addition of nutrients (N, K, P, etc.) and oxygen into the groundwater. Permitting of in-situ
bioremediation is expensive and time consuming, as compared to other alternatives.
Natural or intrinsic bioremediation is presently occurring, as demonstrated in Section 4.1,
and will likely degrade the contaminants to below 2L standards. This active natural
remediation method appears to be the best available technology in some cases for the
future, in terms of cost effectiveness.
Alternatively, the injection of air under pressure into saturated soils (or air sparging), ha~
proven at some sites to be the best available technology to treat volatile contaminants tc
below 2L standards. It is S&ME's understanding that new NCDEHNR guidelines requin
air sparging (AS) be performed only in conjunction with soil vapor extraction (SVE) t,
prevent the spread of fugitive vapors. At this site, SVE was started initially without ai
sparging to remove residual soil hydrocarbons. Sparging was started shortly thereafte
after soil TPH concentrations had reached a low equilibrium state. Both AS and SV I
were performed until the limits of their use had been reached and natural bioremediatio
24
't., ' •
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C
J
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
June 13, 1996
could take over. Information on the AS/SVE remediation previously performed on-site is
discussed in Section 2.2.
Continued air sparging at this site would be unreasonable and unnecessary and would
likely not enable a "clean" closure, based on fluctuating MTBE concentrations at MW-10
and trace chlorinated (1,2-DCA and IPE at MW-9) and semi-volatiles (Bis(2-
ethylhexyl)phthalate, 1 methyl-naphthalene, 2-methyl-naphthalene at RW-2 and MW-12].
These compounds are not as strippable as the BEn< compounds and are not readily
naturally degradable under anaerobic or aerobic (sparging) conditions. A variance
appears to be the more appropriate closure method, as recommended by the State in the
April 1, 1996 letter. To continue operating the air sparge only system does not seem
reasonable compared to the benefits the public would receive.
Based on the historical groundwater quality data (Table 1) and influent (soil vapor) quality
data (Chart 1 ), · we believe that the remediation system has reached the limits of
effectiveness in terms of further remediating this site in an economically reasonable
manner. Intrinsic bioremediation is presently occurring and will continue to degrade the
plume and impede its migration.
25
I• -
NCDEHNR-Groundwater Section
Unocal Derita-Variance Request
S&ME Project No. 1354-92-667
· June 13, 1996
6 COMPLIANCE WOULD PRODUCE FINANCIAL HARDSHIP ON UNOCAL
A total of approximately $751,863 has been spent to date by Unocal Corporation on
assessment and aggressive remediation of the subsurface hydrocarbons using best
available technologies. The state has determined the site to be ineligible for
reimbursement through the petroleum UST State Trust Fund. As you are aware Unocal
sold this site in 1987 and has not made any income on this site since then. It has been
a serious financial hardship to Unocal for the last 9 years. Unocal has remained in
compliance with state and county regulations during assessment and remediation
activities. Appendix 5 includes financial information of cost to date for project.
26
.. . .., . }
NCDEHNR-Groundwater Section S&ME Project No. 1354-92-667
Unocal Derita-Variance Request June 13, 1996
8 NO SPECIAL ORDER OF CONSENT WAS ISSUED BY STATE
No Special Order was ever issued by the state in connection with contaminants in the
proposed area.
28
Within the last week the post office has returned these notices to the Growidwater Section.
You will find enclosed a Public Notice regarding this variance hearing. If county tax
information reveals any updated addresses and/or the identity of the cw-rent owner or owners of this
property, please send this information to:
David Hance
EHNR Division of Water Quality-Groundwater Section
P.O. Box 29578
2728 Capital Boulevard
Raleigh, North Carolina 27626-0578; {fax: [phone])
If possible. we would like your response to this request for i oformation by Wednesday
November S, 1997 so we can contact these property owners prior to the public hearing on November
18, 1997. Jfyou need to discuss this request, feel free to contact M.r. Hance at [phone].
Enclosure
cc: David Hance
Stewart Hines (S& ME Incorporated)
Sincerely,
#?~~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
BBS0Sll6l6l6 ~ 3JI~~3S ~3WO1SnJ
2
t>0fl
NOTICE OF VARIANCE APPLICATION AND HEARING
DEPARTMENT OF ENVIRONMENT, HEALTH AND NATURAL
RESOURCES
DIVISION OF WATER QUALITY
Notice is hereby given of a variance application and public hearing to be held by the Department of
Environment and Natural Resources on behalf of the Environmental Management Commission. The hearing
concerns a request f~r a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202 and the
Corrective Action requirements of 15 A NCAC 2L .0106 (j) for a site at 2932 Gibbon Road in Charlotte, North
Carolina. The Division of Water Quality refers ~o this site identified in the variance request as Groundwater
Incident# 3751. This property, previously owned by the Unocal Corporation of Atlanta. Georgia, was
operated as a retail gasoline outlet until 1987, The pro~ is nowo~ed by Mr.-Frank.Dwyer of Charlotte.
North Carolina. The Unocal Corporation is entirely responsible for cleanup for Groundwater Incident# 3 751.
This variance application from the Unocal Coiporation was received for review by the Department on June
13. 1996. .
The property where the release of petroleum product has occurred is located as follows: Inside the city
limits of Charlotte, North Carolina in the Derita Community. Take Interstate 85 in Charlotte and exit onto
Sugar Creek Road. Travel north on Sugar Creek Road two miles and tum left onto Nevin Road. Travel on
Nevin Road 1/4 of a mile until Gibbon Road crosses Nevin Road. Thi~ site consists of 0.87 acres of land at
2932 Gibbon Road. The site is listed in Mecklenburg County tax records as Parcel Number 045-135-02.
The Unocal Corporation requests that the Environmental Management Commission grant the
following variance to its rules under the authority of ISA NCAC 2L .0113 so that it does the following:
(1) Allow concentrations of Benzen.e, Ethylbenzene, Toluene, Xylene (-o,-m. and p); Methyl Tert-
Butyl Ether (MTBE), Naphthalene, IsopropylEther, Ethylene Dibtomide, 1,2-Dicbloroethane, bis(2-
ethlylhexyl)phthalate {DEHP}, Chloroform, Methylene Chloridei 1-Methyl-Naphthalene, 2-Methyl-·
Naphthalene, Tetmcbloroethylene, Methylene Chloride, and Phenol to remain at levels above lSA
NCAC 2L .0202 Groundwater Quality Standards as analyzed on July 29 1 1996 in all monitoring wells
except for concentrations of substances found by analysis using US Environmental Protection Agency
Method 625 in Monitoring We.11 # 12. Bis(2-ethylhexyl)phthalate {also known as Di(2-
ethylhexyl)phthalate (DEHP)} found by the US Environmental Protection Agency Method 625 in
Monitoring Well# 12 will remain at the concentrations level as analyzed on October 28, 1996. These
concentrations will be required to remain within the property boundaries of 2932 Gibbon Road.
As a condition of the sale of this property in 1987 to Mr. Frank.Dwyer, tank tightness testing was
performed in 1987 on seven existiµg underground storage tanks at the site. All tanks were
subsequently removed from this property by the Unocal Corporation and a closure report filed with
the Mooresville Regional Office in October 1991. One· 4,000 gallon underground storage tank failed
tank tightness testing. A preliminary site assessment submitted on January 14, 1988 confirmed that ·
a release bad occurred from this tank. Since tank removal by the Unocal Corporation, Mr. Frank
Dwyer has used 2932 Gibbon Road as an auto' repair shop (Dwyer's Auto Repair). This property is
located in an area with a mixture of commercial, industrial, and l'esidential development.
1
88S0S1l61616 ~ 3Jl~~3S ~3W01SnJ l6/9121/11
The written comment period for this variance will close at 12:00 PM (midnight) on
December 19, 1997. I am requiring you to complete the hearing officers report and the
recommendation to the Environmental Management Commission Groundwater
Committee by March 19, 1998. This period of time is ninety (90) days after the closing date
for written public comment and allows Division staff ad~quate time to review your
recommendation. Unless significant new site information becomes available after the public
hearing or other extraordinary circumstances occur that dictate a longer review period by the
hearing officer, the earliest date that this variance may be considered by the Groundwater
Committee is February 12, 1998. If your review of the variance shows that there is· a need
for a longer evaluation period, please contact Arthur Mouberry at [phone]:
I appreciate your taking the time to conduct this hearing. The staff will be glad to
assist you through the proceedings. If you have any questions, feel free to call Carl Bailey at
[phone].
Attachments.
cc: Arthur Mouberry
' Carl Bailey
David Hance
2
Public Hearing-Variance Request
November 18, 1997
Variance to 15A NCAC 2L .0202 and 15A NCAC 2L .01060)
2932 Gibbon Road, Charlotte, North Carolina (Derita Community)
(Groundwater Incident Number 3751)
HEARING LOCATED AT:
Mecklenburg County Courthouse
Criminal Courts Building -2nd Floor, Courtroom 2201
700 East Fourth Street -(at 7:00 PM)
HEARING OFFICER'S SPEECH
HEARING OFFICER: Tommy Stevens, Division of Water Quality, Regional
Supervisor (Fayetteville Regional Office)
1-ffiMJNQ Qf'f'Jqg:[l: GOOD EVENING, I WOULD LIKE TO CALL THIS
PUBLIC HEARING TO ORDER. MY NAME IS TOMMY STEVENS, AND I AM
THE DMSION OF WATER QUALITY (FORMERLY THE DIVISION OF
ENVIRONMENTAL MANAGEMENT) REGIONAL SUPERVISOR IN THE
FAYETTEVILLE REGIONAL OFFICE. I HAVE BEEN DESIGNATED HEARING
OFFICER FOR THIS EVENING'S HEARING.
THIS HEARING IS BEING HELD PURSUANT TO NORTH CAROLINA
GENERAL STATUTE 150B-21.2. IN ACCORDANCE WITH THE GENERAL
STATUTES, A PUBLIC NOTICE OF THIS HEARING WAS PUBLISHED IN
1
CONFORMITY WITH 15A NCAC 2L .0113 OF THE GROUNDWATER RULES
AND GENERAL NOTICE HAS BEEN GIVEN IN THE LOCAL PAPER
ACCORDING TO PROCEDURES IN 15A NCAC 2L .0113(e)(l). NOTICES WERE
ALSO DISTRIBUTED TO THE PUBLIC AT LARGE, LOCAL GOVERNMENT
OFFICIALS, WELL OWNERS, AND PROPERTY HOLDERS WITHIN AND NEAR
THE AREA OF THE PROPOSED VARIANCE. THE PUBLIC NOTICE STATED
THAT A MORE DETAILED SUMMARY OF THIS VARIANCE COULD BE
OBTAINED FROM STAFF AND COPIES OF THIS SUMMARY ARE BEING
MADE AVAILABLE TO PERSONS ATTENDING THIS HEARING TONIGHT.
THE PURPOSE OF THIS HEARING IS TO OBTAIN PUBLIC COMMENT AND
PARTICIPATION IN THE CONSIDERATION OF THE VARIANCE REQUEST
FOR THE UNOCAL CORPORATION OF ATLANTA, GEORGIA . THE UNOCAL
CORPORATION IS REQUESTING THIS VARIANCE FROM RULES CONTAINED
IN 15A NCAC 2L GROUNDWATER CLASSIFICATION AND STANDARDS FOR
THE PROPERTY LOCATED AT 2932 GIBBON ROAD. THIS PROPERTY,
PREVIOUSLY OWNED BY THE UNOCAL CORPORATION, IS NOW OWNED
BY MR. FRANK DWYER OF CHARLOTTE, NORTH CAROLINA. UPON
TANK REMOVAL AND SITE RENOVATION BY THE UNOCAL
CORPORATION, MR. DWYER BEGAN TO OPERATE A BUSINESS AT THIS
2
SITE KNOWN AS "DWYER'S AUTO REPAIR". THIS PROPOSED VARIANCE
FOR THE UNOCAL CORPORATION WILL APPLY ONLY TO AN AREA
CONSISTING OF THIS PROPERTY AT 2932 GIBBON ROAD (PARCEL NUMBER
145-135-02). THE UNOCAL CORPORATION ESTIMATES THE TOTAL AREA
OF LAND FOR WHICH THIS VARIANCE IS REQUESTED IS APPROXIMATELY
0.87 ACRES. IN THE SUPPORTING INFORMATION SUBMITTED IN THIS
VARIANCE REQUEST, THE UNOCAL CORPORATION INFORMED THE
DIVISION THAT THIS SITE IS LOCATED WITHIN AN AREA CONTAINING A
MIXTURE OF COMMERCIAL, INDUSTRIAL AND RESIDENTIAL PROPERTIES.
THE APPLICANT PROPOSES TO ALLOW THOSE CONCENTRATIONS OF
BENZENE, TOLUENE, ETHYLBENZENE, XYLENES, NAPHTHALENEt
METHYL-TERT BUTYL ETHER (MTBE), ISOPROPYL ETHER, ETHYLENE
DIBROMIDE, 1,2-DICHLOROETHANE, METHYLENE CHLORIDE,
CHLOROFORM, I-METHYL-NAPHTHALENE, 2-METHYL-NAPHTHALENE,
TETRACHLOROETHYLENE, AND PHENOL TO REMAIN AT LEVELS ABOVE
15A NCAC 2L .0202 STANDARDS AS ANALYZED ON JULY 29, 1996 IN ALL
MONITORING WELLS EXCEPT FOR CONCENTRATIONS OF SUBSTANCES
FOUND BY ANALYSIS USING U.S. ENVIRONMENTAL PROTECTION
AGENCY METHOD 625 IN MONITORING WELL# 12.
3
BIS (2 ETHYLHEXYL)PHTHALATE (ALSO KNOWN AS DEHP} FOUND BY
THE U.S. ENVIRONMENTAL PROTECTION AGENCY METHOD . 625 IN
MONITORING WELL# 12 WILL REMAIN AT THE WILL REMAIN AT THE
CONCENTRATION LEVEL FOUND AS ANALYZED ON OCTOBER 28, 1996.
THESE CONCENTRATIONS WILL BE REQUIRED TO REMAIN WITIIIN THE
PROPERTY BOUNDARIES OF 2932 GIBBON ROAD. THE UNOCAL
CORPORATION ALSO PROPOSES THAT CORRECTIVE ACTIONS REQUIRING
THE APPLICATION OF BEST AVAILABLE TECHNOLOGY IN 15A NCAC 2L
.0106 0) NOT BE APPLIED TO THE AREA WITHIN THE BOUNDARIES OF THE
PROPOSED VARIANCE. THE UNOCAL CORPORATION HAS REPORTED
THAT A TOTAL OF$ 751,863 HAS BEEN EXPENDED TO CLEANUP THIS
SITE. NO CLAIMS FOR REIMBURSEMENT THROUGH THE STATE'S
COMMERCIAL UNDERGROUND STORAGE TANK TRUST FUND HAVE EVER
BEEN FILED BY THE UNOCAL CORPORATION FOR THIS SITE. THE
UNOCAL CORPORATION HAS SUBMITTED SUPPORTING INFORMATION
DEMONSTRATING THAT THE CONTINUED APPLICATION OF BEST
AVAILABLE TECHNOLOGY WILL NOT RESULT IN SIGNIFICANT LONG
TERM REMEDIATION OF THE SITE TO THE GROUNDWATER QUALITY
STANDARDS IN 15A NCAC 2L .0202. THE COMPANY BELIEVES THAT
APPLICATION OF BEST AVAILABLE TECHNOLOGY AT THIS LOCATION IS A
4
SERIOUS FINANCIAL IMPACT WITHOUT EQUAL OR GREATER PUBLIC
BENEFIT.
THIS HEARING WILL CONFORM TO PROCEDURES IN 15A NCAC 2L
.0113. ADDITIONAL COPIES OF THE NOTICE OF VARIANCE APPLICATION
AND HEARING ARE LOCATED IN THIS BUILDING AND ARE AVAILABLE
FOR PUBLIC REVIEW.
A WRITTEN RECORD OF THIS HEARING WILL BE PREPARED WHICH
WILL INCLUDE ALL THE RELEVANT COMMENTS, QUESTIONS, AND
DISCUSSIONS. FOR THIS REASON, THE HEARING IS BEING TAPE
RECORDED. WRITTEN COMMENTS RECEIVED THROUGH DECEMBER 19,
1997 WILL ALSO BE INCLUDED IN THE RECORD. BASED ON THESE
PUBLIC COMMENTS AND ON ANALYSIS BY THE GROUNDWATER STAFF, I
WILL MAKE A RECOMMENDATION TO THE ENVIRONMENTAL
MANAGEMENT COMMISSION. IN MAKING THE FINAL DECISION, THE
ENVIRONMENTAL MANAGEMENT COMMISSION CONSIDERS THE
WRITTEN RECORD, THE RECOMMENDATION OF THE HEARING OFFICER,
THE RECOMMENDATIONS OF DIVISION STAFF, AND THE CONCERNS OF
5
ITS MEMBERS. THE COMMISSION MUST ALSO CONSIDER WHETHER THE
APPLICANT HAS COMPLIED WITH 15A NCAC 2L .0113(g).
IF THE APPLICANT DECIDES THAT THE COMMISSION'S DECISION IS
UN ACCEPT ABLE, A PETITION MAY BE FILED ACCORDING TO
PROCEDURES IN 15A NCAC 2L .0113(h). THE DECISION ON THE VARIANCE
BY THE ENVIRONMENT AL MANAGEMENT COMMISSION IS FINAL AND
BINDING ACCORDING TO THE CONDITIONS SHOWN IN 15A NCAC 2L
.0113(h).
AT THIS TIME I WOULD LIKE TO RECOGNIZE (names of local and state
officials) AND THANK YOU FOR ATTENDING THIS HEARING. I WOULD ALSO
LIKE TO RECOGNIZE THE FOLLOWING PEOPLE FROM THE DIVISION OF
WATER QUALITY (DWQ central office and DWQ regional office personnel).
MR.(staff speaker) OF THE DIVISION OF WATER QUALITY-GROUNDWATER
SECTION MOORESVILLE REGIONAL OFFICE WILL NOW SUMMARIZE THE
PROPOSED VARIANCE WHICH IS THE SUBJECT OF THIS HEARING.
STAFF SPEAKER: (staff speaker summarizes variance request).
6
REARING OFFICER: THANK YOU. WE WILL NOW ACCEPT PUBLIC
COMMENT ON THE PROPOSED VARIANCE. I WOULD LIKE TO REQUEST
THAT EVERYONE FILL OUT A REGISTRATION FORM. AFTER ALL
REGISTERED SPEAKERS HA VE HAD AN OPPORTUNITY TO COMMENT, I
WILL ALLOW ADDITIONAL SPEAKERS AS TIME PERMITS. WHEN YOUR
NAME IS CALLED, PLEASE COME UP TO THE MICROPHONE AND STATE
YOUR NAME AND AFFILIATION. ALL COMMENTS SHOULD BE LIMITED
TO MATTERS THAT ARE RELATIVE TO THE PROPOSED ADOPTION OF THIS
VARIANCE. IF YOUR COMMENTS ARE LONGER THAN THREE MINUTES, I
WOULD LIKE TO REQUEST THAT THEY BE SUBMITTED IN WRITING. I
RESERVE THE RIGHT TO QUESTION SPEAKERS IF THE NEED SHOULD
ARISE.
DMSION OF WATER QUALITY STAFF WILL BE AVAILABLE TO ANSWER
YOUR QUESTIONS IF NECESSARY. I WOULD NOW LIKE TO CALL [first
speaker].
[speakers ... ]
(the hearing officer, referring to TIIE REGISTRATION CARDS, calls each speaker to the
microphone in turn )
7
J-lliARlli9Qfm:G~: THANK YOU [last speaker]. ARE THERE ANY MORE
COMMENTS? SINCE THERE ARE NO MORE COMMENTS, I DECLARE THE
HEARING CLOSED. THE HEARING RECORD WILL REMAIN OPEN UNTIL
12:00 PM (MIDNIGHT) ON DECEMBER 19, 1997. ANYONE WISHING TO
SUBMIT WRITTEN COMMENTS MAY DO SO UNTIL THAT DATE. AFTER
WHICH TIME, THE COMMENTS WILL BE MADE PART OF THE PUBLIC
RECORD AND I SHALL MAKE RECOMMENDATIONS TO THE
ENVIRONMENTAL MANAGEMENT COMMISSION. WRITTEN COMMENTS
MUST BE ADDRESSED TO DAVID HANCE AT THE DMSION OF WATER
QUALITY GROUNDWATER SECTION. THE ADDRESS WRITTEN COMMENTS
NEED TO BE SENT TO IS SHOWN IN THE PUBLIC NOTICE AND IS AS
FOLLOWS:
David Hance
EHNR-DWQ-Groundwater Section
P.O. Box 29578
Raleigh, NC 27626-0578
A FACSIMILE COPY OF WRITTEN COMMENTS MAY BE SENT TO MR
HANCE BY DIALING [phone]. HIS TELEPHONE NUMBER IN RALEIGH
IS [phone]. COMMENTS MAY ALSO BE SENT TO MR. HANCE VIA E-
MAIL BY CONTACTING HIS INTERNET MAILING ADDRESS SHOWN IN THE
PUBLIC NOTICE.
8
IT IS THE DESIRE OF THE COMMISSION TO ALWAYS ACT IN THE BEST
POSSIBLE INTEREST OF THE PUBLIC. THEREFORE, PUBLIC
PARTICIPATION IS A VERY IMPORTANT PART OF THE RULE-MAKING
PROCESS. I WOULD LIKE TO THANK YOU FOR ATTENDING THE HEARING
AND OFFERING YOUR COMMENTS.
9
Directions to Variance Hearing for the Unocal Corporation
(Site located at 2932 Gibbon Road in Charlotte, NC {Derita Community})
HEARING LOCATED AT:
Mecklenburg County Courthouse Criminal Courts Building -2nd Floor, Courtroom 2201
700 East Fourth Street, Charlotte, NC (November 18, 1997 at 7:00 PM)
MOORESVILLE REGIONAL OFFICE STAFF PRESENTER:
Allen Schiff [phone]; fax -[phone]
RALEIGH GROUNDWATER SECTION STAFF RECORDER:
David Hance [phone]; fax-[phone]
HEARING OFFICER: Tommy Stevens [phone]
CONTACT PERSONS AT THE COURT HOUSE -
SGT. PHIL MCGUIRE -[phone]
CAPT. DEATON -[phone]
MAIN NUMBER FOR SHERIFF'S OFFICE· [phone]
FROM FAYETTEVILLE NC:
Take US 401 to Laurinburg, North Carolina and then take US -74 west to Charlotte, NC.
Take US 74 -NC 27 (East Independence Blvd) in the City of Charlotte. Take NC 27 and
get onto McDowell Street. Turn left on McDowell Street and proceed three city blocks
then turn onto East Trade Street. The Criminal Courts Building is located adjacent to the
Government Center. NOTE: East Fourth Street is a one way street going east to west.
East Third Street is a one way street going west to east.
FROM RALEIGH, NC:
Take 1-85 into Charlotte and exit onto NC 16 (Brookshire Freeway). NC 16 will become
1-277. Take 1-277 to S. Graham Street and then go onto East Trade Street. The Criminal
Courts Building is located adjacent to the Government Center. NOTE: East Fourth
Street is a one way street going east to west. East Third Street is a one way street going
west to east.
(See Attached Map)
A
CONFORMITY WITH 15A NCAC 2L .0113 OF THE GROUNDWATER RULES
AND GENERAL NOTICE HAS BEEN GIVEN IN THE LOCAL PAPER
ACCORDING TO PROCEDURES IN 15A NCAC 2L .0113(e)(l). NOTICES WERE
ALSO DISTRIBUTED TO THE PUBLIC AT LARGE, LOCAL GOVERNMENT
OFFICIALS, WELL OWNERS, AND PROPERTY HOLDERS WITHIN AND NEAR
THE AREA OF THE PROPOSED VARIANCE. THE PUBLIC NOTICE STATED
THAT A MORE DETAILED SUMMARY OF THIS VARIANCE COULD BE
OBTAINED FROM STAFF AND COPIES OF THIS SUMMARY ARE BEING
MADE AVAILABLE TO PERSONS ATTENDING THIS HEARING TONIGHT .
THE PURPOSE OF THIS HEARING IS TO OBTAIN PUBLIC COMMENT AND
PARTICIPATION IN THE CONSIDERATION OF THE VARIANCE REQUEST
FOR THE UNOCAL CORPORATION OF ATLANTA, GEORGIA. THE UNOCAL
CORPORATION IS REQUESTING THIS VARIANCE FROM RULES CONTAINED
IN 15A NCAC 2L GROUNDWATER CLASSIFICATION AND STANDARDS FOR
THE PROPERTY LOCATED AT 2932 GIBBON ROAD. THIS PROPERTY,
PREVIOUSLY OWNED BY THE UNOCAL CORPORATION, IS NOW OWNED
BY MR. FRANK DWYER OF CHARLOTTE, NORTH CAROLINA. UPON
TANK REMOVAL AND SITE RENOVATION BY THE UNOCAL
CORPORATION, MR. DWYER BEGAN TO OPERATE A BUSINESS AT THIS
2
D AFT
SITE KNOWN AS "DWYER'S AUTO REPAIR". THIS PROPOSED VARIANCE
FOR THE UNOCAL CORPORATION WILL APPLY ONLY TO AN AREA
CONSISTING OF THIS PROPERTY AT 2932 GIBBON ROAD (PARCEL NUMBER
145-135-02). THE UNOCAL CORPORATION ESTIMATES THE TOTAL AREA
OF LAND FOR WHICH THIS VARIANCE IS REQUESTED IS APPROXIMATELY
0.87 ACRES. IN THE SUPPORTING INFORMATION SUBMITTED IN THIS
VARIANCE REQUEST, THE UNOCAL CORPORATION INFORMED THE
DIVISION THAT THIS SITE IS LOCATED WITHIN AN AREA CONTAINING A
MIXTURE OF COMMERCIAL, INDUSTRIAL AND RESIDENTIAL PROPERTIES.
THE APPLICANT PROPOSES TO ALLOW THOSE CONCENTRATIONS OF
BENZENE, TOLUENE, ETHYLBENZENE, XYLENES, NAPHTHALENE,
METHYL-TERT BUTYL ETHER (MTBE), ISOPROPYL ETHER, ETHYLENE
DIBROMIDE, 1,2-DICHLOROETHANE, METHYLENE CHLORIDE,
CHLOROFORM, 1-METHYL-NAPHTHALENE, 2-METHYL-NAPHTHALENE,
TETRACHLOROETHYLENE, AND PHENOL TO REMAIN AT LEVELS ABOVE
15A NCAC 2L .0202 STANDARDS AS ANALYZED ON JULY 29, 1996 IN ALL
MONITORING WELLS EXCEPT FOR CONCENTRATIONS OF SUBSTANCES
FOUND BY ANALYSIS USING U.S. ENVIRONMENTAL PROTECTION
AGENCY METHOD 625 IN MONITORING WELL# 12.
3
BIS (2 ETHYLHEXYL)PHTHALATE (ALSO KNOWN AS DEHP} FOUND BY
THE U.S. ENVIRONMENTAL PROTECTION AGENCY METHOD 625 IN
MONITORING WELL# 12 WILL REMAIN AT THE WILL REMAIN AT THE
CONCENTRATION LEVEL FOUND AS ANALYZED ON OCTOBER 28, 1996.
THESE CONCENTRATIONS WILL BE REQUIRED TO REMAIN WITHIN THE
PROPERTY BOUNDARIES OF 2932 GIBBON ROAD. THE UNOCAL
CORPORATION ALSO PROPOSES THAT CORRECTIVE ACTIONS REQUIRING
THE APPLICATION OF BEST AVAILABLE TECHNOLOGY IN 15A NCAC 2L
.0106 G) NOT BE APPLIED TO THE AREA WITHIN THE BOUNDARIES OF THE
PROPOSED VARIANCE. THE UNOCAL CORPORATION HAS REPORTED
THAT A TOTAL OF$ 751,863 HAS BEEN EXPENDED TO CLEANUP THIS
SITE. NO CLAIMS FOR REIMBURSEMENT THROUGH THE STATE'S
COMMERCIAL UNDERGROUND STORAGE TANK TRUST FUND HAVE EVER
BEEN FILED BY THE UNOCAL CORPORATION FOR THIS SITE. THE
UNOCAL CORPORATION HAS SUBMITTED SUPPORTING INFORMATION
DEMONSTRATING THAT THE CONTINUED APPLICATION OF BEST
AVAILABLE TECHNOLOGY WILL NOT RESULT IN SIGNIFICANT LONG
TERM REMEDIATION OF THE SITE TO THE GROUNDWATER QUALITY
STANDARDS IN 15A NCAC 2L .0202. THE COMPANY BELIEVES THAT
APPLICATION OF BEST AVAILABLE TECHNOLOGY AT THIS LOCATION IS A
4
RAFT
SERIOUS FINANCIAL IMPACT WITHOUT EQUAL OR GREATER PUBLIC
BENEFIT.
THIS HEARING WILL CONFORM TO PROCEDURES IN 15A NCAC 2L
.0113. ADDITIONAL COPIES OF THE NOTICE OF VARIANCE APPLICATION
AND HEARING ARE LOCATED IN THIS BUILDING AND ARE AVAILABLE
FOR PUBLIC REVIEW.
A WRITTEN RECORD OF THIS HEARING WILL BE PREPARED WHICH
WILL INCLUDE ALL THE RELEVANT COMMENTS, QUESTIONS, AND
DISCUSSIONS. FOR THIS REASON, THE HEARING IS BEING TAPE
RECORDED. WRITTEN COMMENTS RECEIVED THROUGH DECEMBER 19,
1997 WILL ALSO BE INCLUDED IN THE RECORD. BASED ON THESE
PUBLIC COMMENTS AND ON ANALYSIS BY THE GROUNDWATER STAFF, I
WILL MAKE A RECOMMENDATION TO THE ENVIRONMENTAL
MANAGEMENT COMMISSION. IN MAKING THE FINAL DECISION, THE
ENVIRONMENTAL MANAGEMENT COMMISSION CONSIDERS THE
WRITTEN RECORD, THE RECOMMENDATION OF THE HEARING OFFICER,
THE RECOMMENDATIONS OF DIVISION STAFF, AND THE CONCERNS OF
5
. , 'RA
HEt\RIN,Q _QFf1~11R.: THANK YOU [last speaker]. ARE THERE ANY MORE
COMMENTS? SINCE THERE ARE NO MORE COMMENTS, I DECLARE THE
HEARING CLOSED. THE HEARING RECORD WILL REMAIN OPEN UNTIL
12:00 PM (MIDNIGHT) ON DECEMBER 19, 1997. ANYONE WISHING TO
SUBMIT WRITTEN COMMENTS MAY DO SO UNTIL THAT DATE. AFTER
WHICH TIME, THE COMMENTS WILL BE MADE PART OF THE PUBLIC
RECORD AND I SHALL MAKE RECOMMENDATIONS TO THE
ENVIRONMENTAL MANAGEMENT COMMISSION. WRITTEN COMMENTS
MUST BE ADDRESSED TO DAVID HANCE AT THE DIVISION OF WATER
QUALITY GROUNDWATER SECTION. THE ADDRESS WRITTEN COMMENTS
NEED TO BE SENT TO IS SHOWN IN THE PUBLIC NOTICE AND IS AS
FOLLOWS:
David Hance
EHNR-DWQ-Groundwater Section
P.O. Box 29578
Raleigh, NC 27626-0578
A FACSIMILE COPY OF WRITTEN COMMENTS MAY BE SENT TO MR.
HANCE BY DIALING [phone]. HIS TELEPHONE NUMBER IN RALEIGH
IS [phone]. COMMENTS MAY ALSO BE SENT TO MR. HANCE VIA E-
MAIL BY CONTACTING HIS INTERNET MAILING ADDRESS SHOWN IN THE
PUBLIC NOTICE.
8
IT IS THE DESIRE OF THE COMMISSION TO ALWAYS ACT IN THE BEST
POSSIBLE INTEREST OF THE PUBLIC. THEREFORE, PUBLIC
PARTICIPATION IS A VERY IMPORTANT PART OF THE RULE-MAKING
PROCESS. I WOULD LIKE TO THANK YOU FOR ATTENDING THE HEARING
AND OFFERING YOUR COMMENTS.
9
Within the last week the post office has returned these notices to the Groundwater Section.
You will find enclosed a Public Notice regarding this variance hearing. If county tax
information reveals any updated addresses and/or the identity of the current owner or owners of this
property, please send this information to:
David Hance
EHNR Division of Water Quality-Groundwater Section
P.O. Box 29578
2728 Capital Boulevard
Raleigh, North Carolina 27626-0578; {fax: [phone]}
If possible, we would like your response to this request for information by Wednesday
November 5, 1997 so we can contact these property owners prior to the public hearing on November
18, 1997. If you need to discuss this request, feel free to contact Mr. Hance at [phone].
Enclosure
cc: David Hance
Stewart Hines (S& ME Incorporated)
Sincerely,
#!~)~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
2
NOTICE OF VARIANCE APPLICATION AND HEARING
DEPARTMENT OF ENVIRONMENT, HEALTH AND NATURAL
RESOURCES
DIVISION OF WATER QUALITY
Notice is hereby given of a variance application and public hearing to be held by the Department of
Environment and Natural Resources on behalf of the Environmental Management Commission. The hearing
concerns a request f9r a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202 and the
Corrective Action requirements of 15A NCAC 2L .0106 G) for a site at 2932 Gibbon Road in Charlotte, North
Carolina. The Division of Water Quality refers to this site identified in the variance request as Groundwater
Incident# 3751. This property, previously owned by the Unocal Corporation of Atlanta, Georgia, was
operated as a retail gasoline outlet until 1987. The property is now owned by Mr. Frank Dwyer of Charlotte,
North Carolina. The Unocal Corporation is entirely responsible for cleanup for Groundwater Incident# 3 7 51.
This variance application from the Unocal Corporation was received for review by the Department on June
13, 1996.
The property where the release of petroleum product has occurred is located as follows: Inside the city
limits of Charlotte, North Carolina in the Derita Community. Take Interstate 85 in Charlotte and exit onto
Sugar Creek Road. Travel north on Sugar Creek Road two miles and turn left onto Nevin Road. Travel on
Nevin Road 1/4 of a mile until Gibbon Road crosses Nevin Road. This site Consists of 0.87 acres ofland at
2932 Gibbon Road. The site is listed in Mecklenburg County tax records as Parcel Number 045-135-02.
The Unocal Corporation requests that the Environmental Management Commission grant the
following variance to its rules under the authority of 15.A NCAC 2L .0113 so that it does the following:
(1) Allow concentrations of Benzene, Ethylbenzene, Toluene, Xylene (-o,-m, and p), Methyl Tert-
Butyl Ether (MTBE), Naphthalene, Isopropyl Ether, Ethylene Dibromide, 1,2-Dichloroethane, bis(2-
ethlylhexyl)phthalate {DEHP}, Chloroform, Methylene Chloride, 1-Methyl-Naphthalene, 2-Methyl-
Naphthalene, Tetrachloroethylene, Methylene Chloride, and Phenol to remain at levels above 15A
NCAC 2L .0202 Groundwater Quality Standards as analyzed on July 29, 1996 in all monitoring wells
except for concentrations of substances found by analysis using US Environmental Protection Agency
Method 625 in Monitoring Well # 12. Bis(2-ethylhexyl)phthalate {also known' as Di(2-
ethylhexyl)phthalate (DEHP)} found by the US Environmental Protection Agency Method 625 in
Monitoring Well# 12 will remain at the concentrations level as analyzed on October 28, 1996. These
concentrations will be required to remain within the property boundaries of2932 Gibbon Road.
As a condition of the sale of this property in 1987 to Mr. Frank Dwyer, tank tightness testing was
performed in 1987 on seven existing underground storage tanks at the site. All tanks were
subsequently removed from this property by the Unocal Corporation and a closure report filed with
the Mooresville Regional Office in October 1991. One'4,000 gallon underground storage tankfailed
tank tightness testing. A preliminary site assessment submitted on January 14, 1988 confirmed that
a release had occurred from this tank. Since tank removal by the Unocal Corporation, Mr. Frank
Dwyer has used 2932 Gibbon Road as an auto· repair shop (Dwyer' s Auto Repair). This property is
located in an area with a mixture of commercial, industrial, and residential development.
1
The comprehensive site assessment was compl~ted on June 2, 1992 and corrective action plan
for this site was submitted on December 23, 1992. The comprehensive site assessment revealed a
plume of BTEX and dissolved hydrocarbons contaminating subsurface soil arid groundwater. Site
assessment information on file in the Mooresville Regional Office shows that the vertical extent of
this plume to be approximately 90. 78 feet below the ground surface. Dissolved gasoline products have
been defined vertically in the bedrock at this site. This plume was estimated to have covered an area
of approximately 167,199 square feet (3.84 acres) prior to the implementation of corrective actions
by the Unocal Company.
From June 16, 1993 through August 21, 1995, concentrations of substances at this site were
significantly reduced by groundwater cleanup technologies located at the site. Since August 1995
analysis of samples from monitoring wells showed only marginal reductions in the concentration of
substances in groundwater. Analysis of groundwater samples taken on December 1, 1995 and on
February 25, 1996 showed there was no significant increase or decrease in concentrations of Benzene
and other substances at the off-site monitoring wells, while cleanup operations were being conducted.
Based on groundwater analysis of samples from semi-annual monitoring from 1992 through
1995, the Division of Water Quality recommended that air sparging and soil vapor extraction
technologies be turned off to determine if residual contaminants in the soils and subsurface would
recontaminate the groundwater, if no treatment system were operating. Since the cleanup system was
turned off on March 20, 1996, upward "rebounding" of concentrations above the Groundwater Quality
Standards in 15A NCAC 2L .0202 has been noted for some of these monitoring wells. With the
exception of two on-site monitoring wells, the groundwater analysis on July 29, 1996 has shown that
concentrations of substances in monitoring wells have been reduced below detectable limits.
Substances in the two on-site wells near the area where the release occurred remain slightly above the
Groundwater Quality Standards in 15A NCAC 2L .0202.
Based on concentrations of substances found in wells used for recovery or monitoring
contaminants and calculations of the time it would take for substances to migrate to receptors at
surrounding properties, the company does not believe that a variance will result in an adverse impact
to the public. There are no drinking water supply intakes at surface water bodies within½ mile of the
site. Public water supply lines are deemed too shallow to be impacted by substances at 2932 Gibbon
Road.
(2) Allow for the restoration of groundwater without requiring remedial actions in accordance with
15A NCAC 2L .0106G). The Unocal Corporation has submitted supporting information
demonstrating that the continued application of best available technology will not result in significant
long term remediation of the site to the Groundwater Quality Standards contained in 15A NCAC 2L
.0202. This is due to the high probability that continued remediation activities at the site will not
significantly reduce contaminant levels below Groundwater Quality Standards in 15A NCAC 2L
.0202. Since discovery of the release on January 14, 1988 the Unocal Corporation has disposed of
a total of 2,300 tons of petroleum contaminated soil during tank closure.. The Unocal Corporation
has submitted information showing that the total mass of vaporous hydrocarbons recovered by the
SVE system is estimated at 3,400 pounds which is equivalent to 567 gallons of gasoline .. The
company reports that a total of$ 751,863 has been expended to remove tanks, conduct site
assessments, and cleanup soils this site. The Unocal Corporation does not believe that the public will
benefit from continued cleanup using present technology at the site or alternatives discussed and that
a variance is the most effective means of dealing with remaining concentrations.
2
. .. r .
The hearing will be held pursuant to the requirements oftitle15A NCAC 2L .0113 as follows:
CHARLOTTE
Tuesday, November 18, 1997
7:00P.M.
Mecklenburg County Courthouse -Criminal Courts Building
2ND Floor -Courtroom Number 2201
700 East Fourth Street
Oral Comments may be made during the hearing, or written statements may be submitted to the
agency by December 19, 1997. Written copies of oral statements exceeding three minutes are requested.
Oral statements may be limited at the discretion of the hearing officer.
Please forward comments or information requests to:
David Hance
EHNR-DWQ-Groundwater Section
P.O. Box 29578 .
Raleigh, NC 27626-0578
Phone: [phone]; Fax: [phone]
Internet E-Mail Address: [e-mail]
This proposed variance request is available for public inspection at the locations listed below. Copies
may be obtained at each location for a charge of ten cents per page. A summary of information including a
discussion of site cleanup, a detailed discussion of recent and historic on-site and off-site groundwater
monitoring, monitoring of wells to determine the effectiveness of the cleanup systems used at this site, a
discussion of sampling and analysis of inactive and active drinking water supply wells, and cost evaluations
of alternative best available technologies will be made available upon request. Please contact Mr. Hance or
the Mooresville Regional Office for this information.
/4tli}cv\
Dept. of Environment and Natural Resources
Division of Water Quality
P.O. Box 29578
2728 Capital Blvd.
Raleigh, NC 27626-0578
[phone]
A. Preston How:,;;;::)
Director, Division of Water Quality
Dept. of Environment and Natural Resources
Division of Water Quality
Mooresville Regional Office
919 North Main Street
Mooresville, NC 28115
[phone]
3
RESIDENT AND/OR OWNER
6104 KANKWELL BLVD; '
CHARLOTTE, N~
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NC 28269 ':5.
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tl1~t:~
State of North Carolina
Department of Environment
Health ·and Natural Resourc~s
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
The Honorable Pat McCrory
Mayor
City of Charlotte
600 E. Fourth Street -Government Center
Charlotte, NC 28202-2244
Dear Mayor McCrory:
The Department of Environment, Health and Natural Resources has
received a request for a variance from the Groundwater Quality Standards of
15A NCAC 2L .0202 and Corrective Action requirements of 15A NCAC 2L
.0106U) (Groundwater Classifications and Standards). 15A NCAC 2L
.0113(e)(1)(D) requires adequate notice be given to governmental units having
jurisdiction over the geographical area covered by the variance prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please
refer to the enclosure for additional information.
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578•
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
//J?t-e J~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
Mr. Wendell White
Office of the City Manager
City of Charlotte
600 E. Fourth Street -Government Center
Charlotte, NC 28202-2244
Dear Mr. White:
The Department of Environment, Health and Natural Resources has
received a request for a variance from the Groundwater Quality Standards of
15A NCAC 2L .0202 and Corrective Action requirements of 15A NCAC 2L
.01060) (Groundwater Classifications and Standards). 15A NCAC 2L
.0113(e)(1)(D) requires adequate notice be given to governmental units having
jurisdiction over the geographical area covered by the variance prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please
refer to the enclosure for additional information.
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/Jl1&...e ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 9191733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
Mr. Peter Safir
Mecklenburg County Health Department
Office of the Health Director
Area Mental Health
429 Billingsly Road
Charlotte, NC 28211
Dear Mr. Safir:
The Department of Environment, Health and Natural Resources has
received a request for a variance from the Groundwater Quality Standards of
1 SA NCAC 2L .0202 and Corrective Action requirements of 1 SA NCAC 2L
.01060) (Groundwater Classifications and Standards). 1 SA NCAC 2L
.0113(e)(1)(B) requires adequate notice be given to the local health agency units
having jurisdiction over the geographical area covered by the variance prior to
hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please
refer to the enclosure for additional information.
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/fr?t,,-f__~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
North Carolina Department of Transportation
Don Collins, Chief Engineer
P.O. Box 25201
Raleigh, NC 27611
Dear Mr. Collins,
REGARDING: Property Located at 2932
Gibbon Road in Charlotte, North Carolina
(Derita Community); Groundwater
Incident# 3751.
The Department of Environment, Health and Natural Resources has received
a request for a variance from the Groundwater Quality Standards of 15A NCAC 2L
.0202 and Corrective Action requirements of 15A NCAC 2L .0106(j). 15A NCAC 2L
.0113(e)(1)(E) requires adequate notice be given to area properties and adjacent
property owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please
refer to the enclosure for additional information. If you have any questions
concerning this variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/fr!~~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·• Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
RESIDENT AND/OR OWNER
SAMUEL K. SPEARS
6005 ROCKWELL CHURCH RD.
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#lt.-R ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
, Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
RESIDENT AND/OR OWNER
6201 CARVER PLACE
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 1 SA NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
,.fl'lt.,R~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
,Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
RESIDENT AND/OR OWNER
6000 MAPLE STREET
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You v.ill find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Elvd., Raleigh, North Carolina 27604
Sincerely,
#?t..-e ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
• Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO \VHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/frltJ ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
• Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
GARRISON, JAMES
SOUTH CENTRAL OIL COMPANY
2121 CHARLOTTE ROAD
ALBEMARLE, NC 28001
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of ISA NCAC 2L .01060). ISA NCAC 2L -
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
MW~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitl, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
CEO
ATLANTIC STEEL CO, INC.,
P.O. BOX 26156
CHARLOTTE, NC 28221
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg ·
County Tax Id# 045-135-02)
_ The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
$ft..£~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary ·
A. Preston Howard, Jr., P.E., Director
October 16, 1997
KEZIAH, JOHNNY&: MARY
2920 GIBBON ROAD
CHARLOTTE, NC 282i3
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
_ The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106(j). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
//71W ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Vo ice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
----• Sjate of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
BALENTINE, JAMES AND NANCY
3133 JUNE DRIVE
CHARLOTTE, NC 28205
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Co:ri:nnunity -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 21 .0202
and Corrective Action requirements of 15A NCAC 21 .0106G). 15A NCAC 21
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/frlt.J ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
gepartment of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
RESIDENT AND/OR OWNER
2517 PLUM STREET
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
$1W~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Qepartment of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
5919 MAPLE STREET
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P .0. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#'ltJ ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
[;)epartment of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDavitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
6001 MAPLE STREET
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P .0. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#'lµ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
E>epartment of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
RESIDENT AND/OR OWNER
5917 HEWITT DRIVE
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacentto or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 21 .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
471µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
,Department of Environment,
Health and Natural Resources
Division· of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
2407 HEWITT DRIVE
CHARLOTTE, NC 28269
REGARDING; Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of ISA NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). ISA NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#Jt.-£~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
@epartment of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
6310 ROCKWELL CHURCH RD.
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 21 .0202
and Corrective Action requirements of 15A NCAC 21 .0106G). 15A NCAC 21
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will fmd enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
,1'1?W ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919,733-3221 FAX 919,715-0588
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
(;)epartment of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
Octa ber 16, 1997
RESIDENT AND /OR OWNER
6324 ROCKWELL CHURCH RD.
CHARLOTTE, NC 292 69
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106Q). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please. refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
411µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
0epartment of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
6104 KANKWELL BLVD .
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone] .
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd ., Raleigh, North Carofina 27604
Sincerely,
$ft,_£~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX 9'19/715-0588
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
5 7 0 9 NEVIN ROAD
CHARLOTTE NC 2 ' 8269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO \VHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#1µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunif'J/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
•Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
5905 PEACH STREET
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Farmer Unocal
·Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 21 .0202
and Corrective Action requirements of 15A NCAC 21 .0106G). 15A NCAC 21
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#lt..P~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
RESIDENT AND/OR OWNER
2801 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P .0. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
411µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
LOLA EPPERSON
2743 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Fonner Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
471µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone] .
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
471µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Acfon Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
2521 PLUM STREET
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of ISA NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
411µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
2501 EAGLE ROAD
CHARLOTTE, NC 28259
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact Davi_d Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#!µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
CEO
CHARLOTTE DOOR CLOSURE SE RVICE
2927 DERITA AVENUE
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please -refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone] .
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/frltJ ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
OWNER
B]\RRY LIPPARD BODY SHOP
2833 DERITA AVENUE
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO \VHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
_ The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/1?1µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
CEO
PEIOMONT LIFT TRUCK SERVICE
3320 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Fonner Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
$lt.-R ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolin·a
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
3416 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to orWater
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
411µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
CATHLEEN ALEXANDER
3512 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of15A NCAC 2L .0202
and Corrective Action requirements of ISA NCAC 2L .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#lt..R~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
3400 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your l'roperty Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#'ltJ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
(JARVIS)
3415 GIBBON ROAD
CHARLOTTE, NC 28269
, REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#?W~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
(STEVENS)
3436 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Farmer Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 21 .0202
and Corrective Action requirements of 15A NCAC 21 .01060). 15A NCAC 21
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/}'11µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Empl~yer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
3301 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P:O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
///ltJ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
Octa ber 16, 1997
WILLIAM L . BROWN
5705 NEVIN ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P .0. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Rale igh, North Carolina 27604
Sincerely,
477µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
RESIDENT AND/OR OWNER
5220 NEVIN ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Grolllldwater
Incident # 3 7 51-Mecklenburg ·
Collllty Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Grolllldwater Quality Standards of ISA NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). ISA NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
471µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone] .
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
RESIDENT AND/OR OWNER
3000 ALLEN ROAD SOUTH
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P .0. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Elvd., Raleigh, North Carolina 27604
Sincerely,
/jtJµ'~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
. '
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
CEO
EYEBALL ENGINEERING
2925 DERITA AVENUE
CHARLOTTE, NC 28269
REGARDING: Your PropertyAdjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone] .
Enclosure
Groundwater Section
P .0. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh,.North Carolina 27604
Sincerely,
411µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919ll33-3221 FAX 919ll15-0588
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
'Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
CEO
SFLIG CHEMICAL INDUSTRIES
3332 GIBBON ROAD
CHARLOTTE, NC 28269
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Det:ita Community -Groundwater
Incident# 3751-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578 , Raleigh, North Carolina 27626-0578
2728 Cap ital Blvd., Raleigh, North Carolina 27604
Sincerely,
#?d..R~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDavitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
A. A. SHOCK
3424 GIBBON ROAD
CHARLOTTE, NC 28269
, REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#ltJ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
1 I
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
DURANE GAS COMP;.NY
C/0 TAX DEPARTMENT
2317 S. BOULEVARD
CHARLOTTE, NC 28203
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.·
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Cap ital Blvd., Raleigh, North Carolina 27604
Sincerely,
/j'!Jt.,R ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
TAYLOR, THEODORE & LILIAN
P.O. BOX 26386
CHARLOTTE, NC 28221
REGARDING: Your Property Adjacent to or Water
Well near the Fonner Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/J?1W~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A Preston Howard, Jr., P.E., Director
October 16, 1997
DEPT. BROTHERHOOD PENSIONS AND
MINISTERIAL RELIEF-C/0 MS. MILLER
P.O. BOX 34454
CHARLOTTE, NC 28234
REGARDING: Your Property Adjacent to or Water
Well near the Farmer Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TOWHOMITMAYCONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of ISA NCAC 2L .0106G). 15A NCAC 2L
.0l 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
/J1lt..R~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
11 Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
PATTEN, R., MONIN L., & WIVES
5522 SHARON ROAD
CHARLOTTE, NC 28210
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of ISA NCAC 2L .0106(j). 15A NCAC 2L
.Ol 13(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
471µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
,. ·-Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
CEO
VMC PRODUCTS INC.,
P.O. BOX 26426
CHARLOTTE, NC 28213
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg ·
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .01060). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
411µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 16, 1997
GREAsY•s TRUCK REPAIR INC
3028 GIBBON ROAD , .
CHARLOTTE, NC 28269
REGARDING: •Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0i06G). 15A NCAC 21
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P .0. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#'ltJ'~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
·.• Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
CEO
ALLEN T .B. ENTERPRISES, INC.
5032 TEWKSBURY ROAD
CHARLOTTE, NC 28213
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident# 3751-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at (919) 71-5-6189.
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
,111µ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Wayne McDavitt, Secretary
A. Preston Howard, Jr., P.E., Director
October 16, 1997
REGARDING: Your Property Adjacent to or Water
Well near the Former Unocal
Corporation Site at 2932 Gibbon
Road, Charlotte, North Carolina
TO WHOM IT MAY CONCERN:
( Derita Community -Groundwater
Incident # 3 7 51-Mecklenburg
County Tax Id# 045-135-02)
. The Department of Environment, Health and Natural Resources has received a
request for a variance from the Groundwater Quality Standards of15A NCAC 2L .0202
and Corrective Action requirements of 15A NCAC 2L .0106G). 15A NCAC 2L
.0113(e)(l)(E) requires adequate notice be given to area properties and adjacent property
owners prior to hearing.
You will find enclosed a Public Notice regarding the variance hearing. Please refer to
the enclosure for additional information. If you have any questions concerning this
variance request, please contact David Hance at [phone].
Enclosure
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Sincerely,
#1W ~
M. Carl Bailey, Jr.
Assistant Chief for Planning
Groundwater Section
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P .E., Director
October 13, 1997
Ann Long
Legal Advertising
The Charlotte Observer
P.O. Box 32188-28232
'Charlotte, NC 28232·
Dear Ms. Long:
The Department of Environment, Health, and Natural Resources will be holding a Public Hearing
on behalf of the Division of Water Quality to receive public comment on a proposed variance to
groundwater rules for the Unocal Corporation site at 2932 Gibbon Road in Charlotte, North Carolina.
You will find enclosed a Public Notice regarding the meeting. It is requested that you publish the
Public Notice in the Saturday October 18, 1997 issue.
Publication charges will be paid by this office upon receipt o_f your invoice, affidavit, and proof of
publication. Please send the invoice in triplicate and the affidavit in duplicate to the following
individual:
Enclosure
cc: David Hance
Ms. Francis Cotten, DWQ-Budget Office
512 N. Salisbury Street
P.O. Box 29535
Rale~gh, NC 27606-0535
[phone] (ext# 231)
Sincerely,
#1&...e ~
M. Carl Bailey, Jr.,
Assistant Chief for Planning,
Groundwater Section
DWQ-Public Information Officer
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Voice 919/733-3221 FAX [phone]
An Equal Opportunity/Affirmative Action Employer
50% recycled/ 10% post-consumer paper
., ....
NOTICE OF VARIANCE APPLICATION AND HEARING
DEPARTMENT OF ENVIRONMENT, HEALTH AND NATURAL
RESOURCES
DIVISION OF WATER QUALITY
Notice is hereby given of a variance application and public hearing to be held by the Department of
Environment and Natural Resources on behalf of the Environmental Management Commission. The hearing
concerns a request f9r a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202 and the
Corrective Action requirements of15ANCAC 2L .0106 G) for a site at2932 Gibbon Road in Charlotte, North
Carolina. The Division of Water Quality refers to this site identified in the variance request as Groundwater
Incident# 3751. This property, previously owned by the Unocal Corporation of Atlanta, Georgia, was
operated as a retail gasoline outlet until 1987. The property is now owned by Mr. Frank Dwyer of Charlotte,
North Carolina. The Unocal Corporation is entirely responsible for cleanup for Groundwater Incident# 3 7 51.
This variance application from the Unocal Corporation was received for review by the Department on June
13, 1996.
The property where the release of petroleum product has occurred is located as follows: Inside the city
limits of Charlotte, North Carolina in the Derita Community. Take Interstate 85 in Charlotte and exit onto
Sugar Creek Road. Travel north on Sugar Creek Road two miles and turn left onto Nevin Road. Travel on
Nevin Road 1/4 of a mile until Gibbon Road crosses Nevin Road. This site consists of 0.87 acres ofland at
2932 Gibbon Road. The site is listed in Mecklenburg County tax records as Parcel Number 045-135-02.
The Unocal Corporation requests that the Environmental Management Commission grant the
following variance to its rules under the authority of 15A NCAC 2L .0113 so that it does the following:
(1) Allow concentrations of Benzene, Ethylbenzene, Toluene, Xylene (-o,-m, and p ), Methyl Tert-
Butyl Ether (MTBE), Naphthalene, Isopropyl Ether, Ethylene Dibromide, 1,2-Dichloroethane, bis(2-
ethlylhexyl)phthalate {DEHP}, Chloroform, Methylene Chloride, I-Methyl-Naphthalene, 2-Methyl-
Naphthalene, Tetrachloroethylene, Methylene Chloride, and Phenol to remain at levels above 15A
NCAC 2L .0202 Groundwater Quality Standards as analyzed on July 29, 1996 in all monitoring wells
except for concentrations of substances found by analysis using US Environmental Protection Agency
Method 625 in Monitoring Well # 12. Bis(2-ethylhexyl)phthalate {also known as Di(2-
ethylhexyl)phthalate (DEHP)} found by the US Environmental Protection Agency Method 625 in
Monitoring Well# 12 will remain at the concentrations level as analyzed on October 28, 1996 . These
concentrations will be required to remain within the property boundaries of2932 Gibbon Road.
As a condition of the sale of this property in 1987 to Mr. Frank Dwyer, tank tightness testing was
performed in 1987 on seven existing underground storage tanks at the site. All tanks were
subsequently removed from this property by the Unocal Corporation and a closure report filed with
the Mooresville Regional Office in October 1991. One 4,000 gallon underground storage tank failed
tank tightness testing. A preliminary site assessment submitted on January 14, 1988 confirmed that
a release had occurred from this tank. Since tank removal by the Unocal Corporation, Mr. Frank
Dwyer has used 2932 Gibbon Road as an auto repair shop (Dwyer's Auto Repair). This property is
located in an area with a mixture of commercial, industrial, and residential development.
1
The comprehensive site assessment was completed on June 2, 1992 and corrective action plan
for this site was submitted on December 23, 1992. The comprehensive site assessment revealed a
plume of BTEX and dissolved hydrocarbons contaminating subsurface soil and groundwater. Site
assessment information on file in the Mooresville Regional Office shows that the vertical extent of
this plume to be approximately 90. 78 feet below the ground surface. Dissolved gasoline products have
been defined vertically in the bedrock at this site. This plume was estimated to have covered an area
of approximately 167,199 square feet (3.84 acres) prior to the implementation of corrective actions
by the Unocal Company.
From June 16, 1993 through August 21, 1995, concentrations of substances at this site were
significantly reduced by groundwater cleanup technologies located at the site. Since August 1995
analysis of samples from monitoring wells showed only marginal reductions in the concentration of
substances in groundwater. Analysis of groundwater samples taken on December 1, 1995 and on
February 25, 1996 showed there was no significant increase or decrease in concentrations of Benzene
and other substances at the off-site monitoring wells, while cleanup operations were being conducted.
Based on groundwater analysis of samples from semi-annual monitoring from 1992 through
1995, the Division of Water Quality recommended that air sparging and soil vapor extraction
technologies be turned off to determine if residual contaminants in the soils and subsurface would
recontaminate the groundwater, if no treatment system were operating. Since the cleanup system was
turned off on March 20, 1996, upward "rebounding" of concentrations above the Groundwater Quality
Standards in 15A NCAC 2L .0202 has been noted for some of these monitoring wells. With the
exception of two on-site monitoring wells, the groundwater analysis on July 29, 1996 has shown that
concentrations of substances in monitoring wells have been reduced below detectable limits.
Substances in the two on-site wells near the area where the release occurred remain slightly above the
Groundwater Quality Standards in 15A NCAC 2L .0202.
Based on concentrations of substances found in wells used for recovery or monitoring
contaminants and calculations of the time it would take for substances to migrate to receptors at
surrounding properties, the company does not believe that a variance will result in an adverse impact
to the public. There are no drinking water supply intakes at surface water bodies within½ mile of the
site. Public water supply lines are deemed too shallow to be impacted by substances at 2932 Gibbon
Road.
(2) Allow for the restoration of groundwater without requiring remedial actions in accordance with
15A NCAC 2L .01060). The Unocal Corporation has submitted supporting information
demonstrating that the continued application of best available technology will not result in significant
long term remediation of the site to the Groundwater Quality Standards contained in 15A NCAC 2L
.0202. This is due to the high probability that continued remediation activities at the site will not
significantly reduce contaminant levels below Groundwater Quality Standards in 15A NCAC 2L
.0202. Since discovery of the release on January 14, 1988 the Unocal Corporation has disposed of
a total of2,300 tons of petroleum contaminated soil during tank closure.. The Unocal Corporation
has submitted information showing that the total mass of vaporous hydrocarbons recovered by the
SVE system is estimated at 3,400 pounds which is equivalent to 567 gallons of gasoline.. The
company reports that a total of $ 751,863 has been expended to remove tanks, conduct site
assessments, and cleanup soils this site. The Unocal Corporation does not believe that the public will
benefit from continued cleanup using present technology at the site or alternatives discussed and that
a variance is the most effective means of dealing with remaining concentrations.
2
UNOCAL -DERIITA/GWI 3751
WELL OWNERS/ADJACENT PROPERTIES./ AND STAKEHOLDERSSheet1
DWYER, EDWARD F. I DWYER AUTO REPAIR I 2930GIBBON ROAD !CHARLOTTE I NC I 28269 1
HOLT,A.WAYNE UNOCAL CORPORATION 13 CORPORA TE SQUARE, N.E. ATLANTA GA 30329
HINES, STEWART M., L.G. S&ME INCORPORATED 9751 SOUTHERN PINE BLVD. CHARLOTTE NC 28273
BALENTINE, JAMES AND NANCY 3133 JUNE DRIVE CHARLOTTE NC 28205 RE: PARCEL 045-135-01
KEZIAH, JOHNNY & MARY 2920 GIBBON ROAD CHARLOTTE NC 28213 RE: PARCEL 045-135-03
SORRELLS, RONALD & MARILU REA 3401 GOVERNORS ISLAND ROAD DENVER NC 28037 RE: PARCEL 045-135-04
CEO ATLANTIC STEEL CO, INC., P.O. BOX 26156 CHARLOTTE NC 28221 RE: PARCEL 045-135-07
GARRISON, JAMES SOUTH CENTRAL OIL COMPANY 2121 CHARLOTTE ROAD ALBEMARLE NC 28001 RE: PARCEL 045-143~4
GARRISON, JAMES SOUTH CENTRAL OIL COMPANY 2121 CHARLOTTE ROAD ALBEMARLE NC 28001 RE: PARCEL 045-14~8
CEO ALLEN T.B. ENTERPRISES, INC. 5032 TEWKSBURY ROAD CHARLOTTE NC 28213 RE: PARCEL 045-143~7
CEO VMC PRODUCTS INC., P.O. BOX 26426 CHARLOTTE NC 28213 RE: PARCEL 045-372-20
PATTEN, R., MONIN L., & WIVES 5522 SHARON ROAD CHARLOTTE NC 28210 RE: PARCEL 045-372-19
DURANEGASCOMPANY C/O TAX DEPARTMENT 2317 S . BOULEVARD CHARLOTTE NC 28203 RE: PARCEL 043-026-29
TAYLOR, THEODORE&-LIUAN P.O . BOX 26386 CHARLOTTE NC 28221 RE: PARCEL 043-026-28
GREASY'S TRUCK REPAIR, INC. 3028 GIBBON ROAD CHARLOTTE NC 28269
DEPT. BROTHERHOOD PENSIONS AND MINISTERIAL RELIEF-C/O MS. MILLER P.O . BOX 34454 CHARLOTTE NC 28234 RE: PARCEL 043-026-26
RESIDENT AND/OR OWNER 5220 NEVIN ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 3000 ALLEN ROAD SOUTH CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 2501 EAGLE ROAD CHARLOTTE NC 28269
CEO CHARLOTTE DOOR CLOSURE SERVICE 2927 DERITA A VENUE CHARLOTTE NC 28269
CEO EYEBALL ENGINEERING 2925 DERITA AVENUE CHARLOTTE NC 28269
OWNER BARRY LIPPARD BODY SHOP 2833 DERITA A VENUE CHARLOTTE NC 28269
CEO PEIDMONT LIFT TRUCK SERVICE 3320 GIBBON ROAD CHARLOTTE NC 28269
CEO SFLIG CHEMICAL INDUSTRIES 3332 GIBBON ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 3400 GIBBON ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 3416 GIBBON ROAD CHARLOTTE NC 28269
A.A.SHOCK 3424 GIBBON ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER (STEVENS) 3436 GIBBON ROAD CHARLOTTE NC 28269
Page 1
UNOCAL -DERIITA/GWI 3751
WELL OWNERS/ADJACENT PROPERTIES./ AND STAKEHOLDERSSheet1
CATHLEEN ALEXANDER 3512 GIBBON ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER (JARVIS) 3415GIBBON ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 3301 GIBBON ROAD CHARLOTTE NC 28269
WILLIAM L. BROWN 5705 NEVIN ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 5709 NEVIN ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 2801 GIBBON ROAD CHARLOTTE NC 28269
LOLA EPPERSON 2743 GIBBON ROAD CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 5905 PEACH STREET CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 5900 PEACH STREET CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 2521 PLUM STREET CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 2517 PLUM STREET CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 5919 MAPLE STREET CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 6001 MAPLE STREET CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 6000 MAPLE STREET CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 2407 HEWITT DRIVE CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 5917 HEWITT DRIVE CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 6118 ROCKWELL CHURCH RD. CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 6310 ROCKWELL CHURCH RD. CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 6324 ROCKWB.L CHURCH RD. CHARLOTTE NC 28269
RESIDENT AND/OR OWNER SAMUEL K. SPEARS 6005 ROCKWELL CHURCH RD. CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 6104 KANKWELL BLVD. CHARLOTTE NC 28269
RESIDENT AND/OR OWNER 6201 CARVER PLACE CHARLOTTE NC 28269
Page2
NOTICE OF VARIANCE APPLICATION AND HEARING
DEPARTMENT OF ENVIRONMENT, HEALTH AND NATURAL
RESOURCES
DIVISION OF WATER QUALITY
Notice is hereby given of a variance application and public hearing to be held by the Department of
Environment and Natural Resources on behalf of the Environmental Management Commission. The hearing
concerns a request f9r a variance from the Groundwater Quality Standards of 15A NCAC 2L .0202 and the
Corrective Action requirements of 15A NCAC 2L .0106 G) for a site at 2932 Gibbon Road in Charlotte, North
Carolina. The Division of Water Quality refers to this site identified in the variance request as Groundwater
Incident# 3751. This property, previously owned by the Unocal Corporation of Atlanta, Georgia, was
operated as a retail gasoline outlet until 1987. The property is now owned by Mr. Frank Dwyer of Charlotte,
North Carolina. The Unocal Corporation is entirely responsible for cleanup for Groundwater Incident# 3 7 51.
This variance application from the Unocal Corporation was received for review by the Department on June
13, 1996.
The property where the release of petroleum product has occurred is located as follows: Inside the city
limits of Charlotte, North Carolina in the Derita Community. Take Interstate 85 in Charlotte and exit onto
Sugar Creek Road. Travel north on Sugar Creek Road two miles and tum left onto Nevin Road. Travel on
Nevin Road 1/4 of a mile until Gibbon Road crosses Nevin Road. This site consists of 0.87 acres of land at
2932 Gibbon Road. The site is listed in Mecklenburg County tax records as Parcel Number 045-135-02.
The Unocal Corporation requests that the Environmental Management Commission grant the
following variance to its rules under the authority of 15A NCAC 2L .0113 so that it does the following:
(1) Allow concentrations of Benzene, Ethylbenzene, Toluene, Xylene (-o,-m, and p), Methyl Tert-
Butyl Ether (MTBE), Naphthalene, Isopropyl Ether, Ethylene Dibromide, 1,2-Dichloroethane, bis(2-
ethlylhexyl)phthalate {DEHP}, Chloroform, Methylene Chloride, I-Methyl-Naphthalene, 2-Methyl-
Naphthalene, Tetrachloroethylene, Methylene Chloride, and Phenol to remain at levels above 15A
NCAC 2L .0202 Groundwater Quality Standards as analyzed on July 29, 1996 in all monitoring wells
except for concentrations of substances found by analysis using US Environmental Protection Agency
Method 625 in Monitoring Well # 12. Bis(2-ethylhexyl)phthalate {also known as Di(2-
ethylhexyl)phthalate (DEHP)} found by the US Environmental Protection Agency Method 625 in
Monitoring Well# 12 will remain at the concentrations level as analyzed on October 28, 1996. These
concentrations will be required to remain within the property boundaries of 2932 Gibbon Road.
As a condition of the sale of this property in 1987 to Mr. Frank Dwyer, tank tightness testing was
performed in 1987 on seven existing underground storage tanks at the site. All tanks were
subsequently removed from this property by the Unocal Corporation and a closure report filed with
the Mooresville Regional Office in October 1991. One 4,000 gallon underground storage tank failed
tank tightness testing. A preliminary site assessment submitted on January 14, 1988 confirmed that
a release had occurred from this tank. Since tank removal by the Unocal Corporation, Mr. Frank
Dwyer has used 2932 Gibbon Road as an auto repair shop (Dwyer's Auto Repair). This property is
located in an area with a mixture of commercial, industrial, and residential development.
1
The comprehensive site assessment was completed on June 2, 1992 and corrective action plan
for this site was submitted on December 23, 1992. The comprehensive site assessment revealed a
plume of BTEX and dissolved hydrocarbons contaminating subsurface soil and groundwater. Site
assessment information on file in the Mooresville Regional Office shows that the vertical extent of
this plume to be approximately 90. 78 feet below the ground surface. Dissolved gasoline products have
been defined vertically in the bedrock at this site. This plume was estimated to have covered an area
of approximately 167,199 square feet (3 .84 acres) prior to the implementation of corrective actions
by the Unocal Company.
From June 16, 1993 through August 21, 1995, concentrations of substances at this site were
significantly reduced by groundwater cleanup technologies located at the site. Since August 1995
analysis of samples from monitoring wells showed only marginal reductions in the concentration of
substances in groundwater. Analysis of groundwater samples taken on December 1, 1995 and on
February 25, 1996 showed there was no significant increase or decrease in concentrations of Benzene
and other substances at the off-site monitoring wells, while cleanup operations were being conducted.
Based on groundwater analysis of samples from semi-annual monitoring from 1992 through .
1995, the Division of Water Quality recommended that air sparging and soil vapor extraction
technologies be turned off to determine if residual contaminants in the soils and subsurface would
recontaminate the groundwater, if no treatment system were operating. Since the cleanup system was
turned off on March 20, 1996, upward "rebounding" of concentrations above the Groundwater Quality
Standards in 15A NCAC 2L .0202 has been noted for some of these monitoring wells. With the
exception of two on-site monitoring wells, the groundwater analysis on July 29, 1996 has shown that
concentrations of substances in monitoring wells have been reduced below detectable limits.
Substances in the two on-site wells near the area where the release occurred remain slightly above the
Groundwater Quality Standards in 15A NCAC 2L .0202.
Based on concentrations of substances found in wells used for recovery or monitoring
contaminants and calculations of the time it would take for substances to migrate to receptors at
surrounding properties, the company does not believe that a variance will result in an adverse impact
to the public. There are no drinking water supply intakes at surface water bodies within½ mile of the
site. Public water supply lines are deemed too shallow to be impacted by substances at 2932 Gibbon
Road.
(2) Allow for the restoration of groundwater without requiring remedial actions in accordance with
15A NCAC 2L .01060). The Unocal Corporation has submitted supporting information
demonstrating that the continued application of best available technology will not result in significant
long term remediation of the site to the Groundwater Quality Standards contained in 15A NCAC 2L
.0202. This is due to the high probability that continued remediation activities at the site will not
significantly reduce contaminant levels below Groundwater Quality Standards in 15A NCAC 2L
.0202. Since discovery of the release on January 14, 1988 the Unocal Corporation has disposed of
a total of2,300 tons of petroleum contaminated soil during tank closure.. The Unocal Corporation
has submitted information showing that the total mass of vaporous hydrocarbons recovered by the
SVE system is estimated at 3,400 pounds which is equivalent to 567 gallons of gasoline .. The
company reports that a total of $ 751,863 has been expended to remove tanks, conduct site
assessments, and cleanup soils this site. The Unocal Corporation does not believe that the public will
benefit from continued cleanup using present technology at the site or alternatives discussed and that
a variance is the most effective means of dealing with remaining concentrations.
2
Time ._Sensitive
~· £1'f?,;1'~_!.•;. ~ • . •·•-u.,._ ......... ~.~, ... _'.~-:..,,.,;~f.,_, ... ,:y_ .. ·_'·-.. '. .,,··~·. :~ ,:
IY,l..eamD ! ~'=-· .
To:
From:
Subject:
Date:
Donna Pittman
David Hance {])f)--
Public Notice -Variance -Unocal Derita ... 2932 Gibbon Road (GWI # 3751)
October 7, 1997
Here is the public notice for a proposed variance for Unocal Derita. You will
recall that this variance is for a site that has been cleaning up groundwater contamination from
petroleum contaminated soils. On September 5, 1997 the Director gave the Groundwater
Section approval to bring this variance to public hearing. Arthur Mouberry has reviewed this
notice of the public hearing and is satisfied that it meets the requirements of 15A NCAC 2L
.0113 . The date of the hearing has been set for November 18, 1997 in Charlotte, NC at 7:00
P.M .. Mt. Tommy Stevens, Division of Water Quality Region Supervisor in the Fayetteville
Region, has agreed to be the hearing officer for this variance. Please note that the summary
referred to in the notice on the last Paragraph of page 3 is information that the Director reviewed
on September 5, 1997.
Once this notice is. signed by the Director, the Groundwater Section will need to
get an adequate number of copies made to notice adjacent properties, area well owners, and other
individuals. Up on com pletin ~ the Director's review and si~nature o f this notice, I would be
glad to come hv and pick this up. If possible, we would like to get the signed notice
ready by 10:00 ~ on Monday, October 13, 199 7. Please feel free to contact me at
715-6189 or my E-Mail address if you have questions.
Due to the September EMC Meetings, the necessity to complete activities in order
to file Temporary RBCA UST Rules, and the need to getrule changes for the permanent 15A
NCAC 2L .0115 in the EMC information packet for the October EMC Groundwater Committee
and EMC meetings, completion of this notice was delayed until this week.
CC: Arthur Mouberry·
Carl Bailey
State of North Carolina
Department of Environment
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
.NA
D E HNR
September 5, 1997
MEMORANDUM
TO: Arthur Mouberry, P.E.
Chief, Groundwater Section
FROM: A. Preston Howard,Jr. P.0 pJ..
z
SUBJECT: Variance Request for the Former Unocal Facility at 29,¢' Gibbon Road in
Derita, North Carolina (GW Incident Number 3751).
I have reviewed the attached package submitted in support of a request for a variance
as outlined in 15A NCAC 2L .0113. Based on the information that has been submitted, I
have determined that sufficient information exists to concur that this variance should
proceed with public notice and hearing as outlined in the rules. Please provide public notice
in accordance with 15A NCAC 2L .0113(e) so that the Division can receive public input
prior to final action on this variance request.
cc: Groundwater Section Assistant Chiefs
David Hance
Mooresville Regional Hydrogeologic Supervisor
Groundwater Section
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
Voice 919/733-3221 FAX [phone]
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DIVISION OF WATER QUALITY
GROUNDWATER SECTION
August 28, 1997
MEMORANDUM
To:
From:
Subject:
Preston Howard
Arthur Mouberry~
Request for Variance from 15A NCAC 2L .0202 and 15A
NCAC 2L .0106(j) for a Site Owned by the Unocal Corporation of Atlanta,
Georgia at 2932 Gibbon Road in Derita, North Carolina (Mecklenburg
County) {Groundwater Incident Number 3751}.
Unocal Corporation operated a retail gasoline station at 2932 Gibbon Road in
Derita, North Carolina up until 1987. In 1987 the Unocal Corporation sold this property
to Mr. Frank Dwyer of Charlotte, North Carolina. As a condition of the sale of this
property tank tightness testing was performed in 1987 on seven existing underground
storage tanks at the site. All tanks were subsequently removed from this property by the
Unocal Corporation and a closure report filed with the Mooresville Regional Office in
October 1991. One 4,000 gallon underground storage tank failed tank tightness testing. A
preliminary site assessment submitted on January 14, 1988 confirmed that a release had
occurred from this tank. Since tank removal by the Unocal Corporation, Mr. Frank Dwyer
has used 2932 Gibbon Road as an auto repair shop (Dwyer's Auto Repair). The Unocal
Corporation is entirely responsible for cleanup of this release which is shown in Division
of Water Quality files as Groundwater Incident Number 3751.
Pursuant to title 15A NCAC 2L .0113(c) variance applications are required to
contain specific information so that they can be adequately reviewed. The Unocal
Corporation variance request is contained in a report titled "Variance Re q uest Incident No.
3751 Unocal Cor poration Former Unocal Facility # 9342-811 Derita . North Carolina
S&ME Pro ject No. 1354-92-667 (l une 1996)". The Mooresville Regional Office review of
this variance request is contained a letter to the Groundwater Section Chief dated
September 23, 1996. Attached also are memoranda relating to groundwater monitoring
and cleanup at the deep monitoring well (Monitoring Well 12) at this site. On August 12,
1996 the Division of Epidemiology raised concerns about the concentration of a substance
in this well and the potential health impacts that this may pose to drinking water wells in
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the general area. On October 23, 1996 the Unocal Corporations was requested to provide
additional information to address these concerns. On November 8, 1996 the company
sent it's response to the issues raised by the Division of Epidemiology. The results of
special groundwater monitoring from Monitoring Well 12 is shown in a letter from the
Unocal Corporation's environmental consultant.dated for November 8, 1996. In addition,
the Groundwater Section requested that the Unocal Corporation provide additional
laboratory analysis to assist staff in completing it's review of this request and this
information is contained in the report titled Jul y 29 . 1996 Groundwater Data for Unocal-
Derita. In addition, the company sent the I ul y 31 , 1997 Vista Site Assessment Re p ort to
provide the Groundwater Section with an update on the potential sources of groundwater
contamination in the general area around 2932 Gibbon Road.
The comprehensive site assessment was completed on June 2, 1992 and corrective
action plan for this site was submitted on December 23, 1992. Both of these items are on
file at the Mooresville Regional Office. The information submitted by S&ME Incorporated
on behalf of Unocal Corporation appears to meet the requirements of 1 SA NCAC 2L
.0113(c) and is summarized as follows:
Rule .0113 (c)(1 ): Resolution by the County or governin g Board:
The Unocal Corporation has always been a privately owned company. No
resolution is necessary.
Rule .0113 {c H2): A descri ption of past. existin g or p ro posed activities that would result in a
discharge of contaminants into groundwater:
The former Unocal site (Dwyer's Auto Repair) is located inside the town
limits of Derita, North Carolina at 2932 Gibbon Road (Mecklenburg County
Parcel Number 0-45-135-02). The report titled "Variance Re quest Incident No.
3751 Unocal Corporation Former Unocal Facility # 9342-811 Derita , North
Carolina S&ME Pro ject No. 1354-92-667 (l une 1996)" contains the relevant
information about this site. This facility is at the corner of Gibbon Road and Nevin
Road as shown in Figure 4 of the report. The Unocal site consists of
approximately 0.87 acres of land. On January 14, 1988 a release of an unknown
quantity of gasoline was discovered at the northeast corner of the site near Nevin
Road during tank removal and site renovation. Seven underground storage tanks
were removed from this site consisting of four 4,000 gallon gasoline tanks, one
2,000 gallon diesel fuel tank, one 550 gallon waste oil tank, and one 550 gallon
kerosene steel tank. Piping, dispensers and other aperient devices were also
removed. The Unocal Corporation reports that the Division approved
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Comprehensive Site Assessment and Corrective Action Plans in 1992 and 1993
respectively.
The Unocal Corporation began cleanup of this site on July 16, 1993.
All potential sources of groundwater contamination were identified at this
property by the company. This property at 2932 Gibbon Road in Derita, North
Carolina, formerly owned by the Unocal Corporation, and all adjacent properties
are in an area with a mixture of commercial, industrial, and residential
development.
The comprehensive site assessment revealed a plume BTEX and dissolved
hydrocarbons contaminating subsurface soil and groundwater. This area was
located near the northeast property line approximately 40 feet east-northeast of
the area where the Unocal Corporation retail outlet had it's gasoline pump
islands. Site assessment information on file in the Mooresville Regional Office
shows that the vertical extent of this plume to be approximately 90.78 feet below
the ground surface. Dissolved gasoline products have been defined vertically in
the bedrock at this site. This release occurred in unconsolidated materials above
the bedrock.
The Unocal Corporation implemented cleanup of this site on July 16, 1993.
During tank removal 2,300 tons of gasoline contaminated soil was extracted,
treated with passive bioremediation on-site, and later transported off-site for
treatment. The company believes that the majority of gasoline contaminated soils
were removed from this site and thus the predominant source of contaminants
that would have likely had an impact on groundwater. The cleanup system used
by the Unocal Corporation consisted of a combination of air sparging and soil
vapor extraction of volatile organic substances the subsurface materials to remove
remaining contaminants from the site.
The Division of Water Quality required the Unocal Corporation to perform
groundwater monitoring to determine the vertical and lateral extent of
contamination at the site. From March 4, 1992 through July 29, 1996 the
company conducted comprehensive groundwater sampling at all six on-site
monitoring wells. The deepest of the monitoring well constructed at this site was
Monitoring Well 12 and it is 90.78 feet deep below the land surface as shown in
Table 2 of the report titled "Variance Re q uest Incident No. 3751 Unocal
Cor p oration Former Unocal Facilit y # 9342-811 Derita. North Carolina S&ME
Pro ject No. 1354-92-667 (l une 1996)" .
Benzene was found in eight of eleven monitoring wells. The highest
concentration found in a monitoring well in exceedence of the 15A NCAC 2L
.0202 Groundwater Quality Standard for Benzene during this sampling event was
5.50 milligrams per Liter (mg/L) or 5,500 micrograms per Liter (ug/L) in
Monitoring Well 10 on March 4, 1993. The Groundwater Quality Standard for
Benzene is 0.001 milligrams per Liter (mg/L) or 1.0 micrograms per Liter. This
sampling event also revealed the presence of Toluene at 11.0 milligrams per liter
or 11,000 micrograms/Liter (ug/L) in Monitoring Well 14. The Groundwater
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Quality Standard for Toluene is 1.0 milligram per Liter (mg/L) or 1,000
micrograms per Liter (ug/L). Ethylbenzene also appeared in Monitoring Well 14
at a concentration level of 3.7 milligrams/liter (mg/L) or 3,700 micrograms/Liter
(ug/L). The Groundwater Quality Standard for Ethylbenzene is 0.029 milligrams
per Liter (mg/L) or 29.0 micrograms per Liter (ug/L). The highest concentration
of Xylene found at this site 13.2 milligrams per liter (mg/L) or 13,200 micrograms
per liter in Monitoring Well 14 on March 4, 1993. The Groundwater Quality
Standard for Xylene is 0.530 milligrams per Liter (mg/L) or 530 micrograms per
Liter (ug/L). The highest Methyl Tert Butyl Ether (MTBE) concentration found at
this site was 6.3 milligrams per liter (mg/L) or 6,300 micrograms per liter (ug/L) in
Monitoring Well 10. The Groundwater Quality Standard for MTBE is 0.200
milligrams per Liter (mg/L) or 200 micrograms per Liter (ug/L). The highest
lsopropyl Ether (IPE) concentration found at this site was 0.370 milligrams per
liter (mg/L) or 370 micrograms per liter (ug/L) in Monitoring Well 14 on August
13, 1993. The Groundwater Quality Standard for IPE is 0.07 milligrams per Liter
(mg/L) or 70 micrograms per Liter (ug/L). Ethylene Dibromide (EDB) appeared in
Monitoring Well 3 at a concentration level of 1.88 X 10·3 milligrams per Liter
(mg/L) or 18.8 micrograms per Liter (ug/L) on August 11, 1994. The Groundwater
Quality Standard for EDB is 4 X 10·7 milligrams per Liter (mg/L) or 4 X 104
micrograms per Liter (ug/L). The highest concentration of Bis(2-
ethylhexyl)phthalate {also known as Di(2-ethlyhexyl)phthalate (DEHP)} appeared
in Monitoring Well 12 (deep well) August 18, 1995. The highest concentration of
DEHP appeared in this well at a concentration of 2.70 milligrams per liter (mg/L)
or 2,700 micrograms per Liter (ug/L). The Groundwater Quality Standard for
DEHP 3.00 x 10·3 milligrams per liter (mg/L) or 3.00 micrograms per Liter (ug/L).
All monitoring wells at this site have at one time or another shown concentrations
of substances above the Groundwater Quality Standards from March 4, 1992
through April 24, 1996.
The Division required the Unocal Corporation to evaluate the effectiveness
of groundwater cleanup efforts by examining conce_ntrations of substances in
recovery wells used as sumps to collect free product and dissolved hydrocarbons
from the site. This was necessary to understand the effect that air sparging and
soil vapor extraction cleanup technologies have had on concentrations of
constituents at the site. Samples were obtained from four recovery wells from
April 1993 through April 1996. These wells are located around the area which
formerly consisted of the Unocal Corporation's pump islands.
Except for Benzene, the highest concentrations of substances found in a in
any of the recovery wells occurred on August 13, 1993 in Recovery Well 2.
Except for lsopropyl Ether (IPE), all concentrations of the remaining substances
reported on August 13, 1993, were in exceedence of the 15A NCAC 2L .0202
Groundwater Quality Standards.
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The concentrations of substances that appeared in Recovery Well 2 on
August 13, 1993 are as follows:
CQrsCErsIRAIIQrs CONCENTRATION (;ROUNDWAIER
SUBSTANCE <io mitrngrnms {io Milligrams QUALITY
per liter {ug/L}) per liter {mg/L}) STANDARD (mg/U
Toluene 16,000 16.0 1.000
Ethylbenzene 2,200 2.2 0.029
Xylene 17,000 17.0 0.530
Methyl Tert
Butyl Ether (MTBE) 280 0.280 0.200
Ethylene Dibromide 1.6 1.6 X 10"3 4 X 10"7
The highest concentration of Benzene appeared on August 23, 1993 in
Recovery Well 2 at a concentration of 1.5 milligrams/Liter (mg/L) or 1,500
micrograms/Liter. The Groundwater Quality Standard for Benzene is 0.001
milligrams per Liter (mg/L) or 1.0 micrograms per Liter. Since August 1993,
concentrations of substances in this well have decreased to the extent that they no
longer exceed the Groundwater Quality Standards in 15A NCAC 2L .0202. This
recovery well is located to the southwest of the former tank pit area were the
release of gasoline occurred. It must be noted that in August 1993 Recovery Well
1 was converted to a vacuum well. At this same time Recovery Wells 3 and 4
were converted to dual vacuum and air sparging wells. Since cleanup was
initiated by Unocal, levels of contaminants in groundwater have been significantly
reduced in monitoring wells and recovery wells as shown in Table #1 of the l.Y.1.¥.
29. 1996 Groundwater Data for Unocal-Derita.
Based on the results of the April 1996 monitoring, the Unocal Corporation
informed the Mooresville Regional Office that it intended to request a variance at
this site. As shown in Appendix V of the report a letter from Mr. A. Wayne Holt
of the Unocal Corporation stated in this letter that the company has utilized best
available technology and has " .... aggressively pursued remediation of this site .... ".
They have specifically requested a variance that would specify "closure" of this
site. This variance encompasses the entire property at 2932 Gibbon Road in
Derita, North Carolina.
Potential sources of groundwater contamination in the area are shown on
maps located on Figure 4 and Figure 5 of the report titled "Variance Request
Incident
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No. 3751 Unocal Corporation Former Unocal Facility# 9342-811 Derita. North
Carolina S&ME Proiect No. 1354-92-667 {lune 1996)" . Additional information on
the potential sources of groundwater contamination can be found in the luly 31.
1997 Vista Sjte Assessment Report. These potential sources are identified as
follows:
1) An auto body and repair shop presently owned by Dwyer
Auto Repair located on the property once owned by the Unocal
Corporation at 2932 Gibbon Road;
2) A warehouse at 6810 Nevin Road that is located northeast of the
site;
3) An industrial warehouse at 5600 Nevin owned by the Atlantic Steel
Supply Company Incorporated located southeast of the site;
4) A retail gasoline station/convenience store identified as "Handy
Pantry" presently owned by South Central Oil Company at 2947
Gibbon Road. This adjacent property is located to the southeast of
the site (Mecklenburg County Tax ID 045-143-94). There are a total
of four underground storage tanks at this site including three 10,000
gallon gasoline tanks and one 8,000 gallon tank for kerosene. Page
10 of the luly 31, 1997 Vista Site Assessment Report shows these
tanks are presently in use and are made of "fiberglass reinforced
plastic". Leak monitoring is described as "present" for these tanks.
5) An industrial warehouse at 3001 Gibbon Road known as "Delta Unit
Rebuilders" and owned by VMC Products Incorporated of Charlotte,
North Carolina. Page 11 of the !uly 31. 1997 Vista Site
Assessment Report shows that this site generates between 100
kilograms and 1,000 kilograms per month of "non-acutely hazardous
waste";
6) A prefabricated industrial warehouse located at 3008 Gibbon Road
identified as the Durane Gas Company.
7) An industrial warehouse at 3020 Gibbon Road owned by Theodore
W. Taylor and his wife Lillian Y. Taylor. This property was formerly
known as the "Gamble Pallet Company".
8) An industrial warehouse at 3028 Gibbon Road known as "Greasy's
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Truck Repair, Incorporated ".
9) Five underground storage tanks at the Derita Amoco at 6242 Derita
Road. Each tank holds 5,000 gallons of gasoline. This property is
within 1/8 of a mile northeast of the former Unocal Corporation site
at 2932 Gibbon Road. Pages 10 and 11 of the I ul y 31 . 1997 Vista
Site Assessment Re port shows that these tanks have been removed
and leak monitoring is described as "present";
10) An Amoco Oil Company site at 2600 West Sugar Creek Road in
Charlotte located 0.48 miles southeast of the site. Page 12 of the
July 31. 1997 Vista Site Assessment Report shows that a leak was
discovered from an underground storage tank on May 1, 1989 and
that remedial action has been taken by the company;
11) An state listed inactive hazardous waste site exists within a mile of
the former Unocal Corporation site at 2932 Gibbon Road. This site
is known as the Van Waters Rogers at the Atando Industrial Park in
Charlotte, North Carolina. Page 15 of the Vista Site Assessment
Report shows that organic substances are believed to be at this
location;
12) There is a solid waste facility at 707 Blockbuster Road within ½
miles of the former Unocal Corporation site at 2932 Gibbon Road .
This property is owned by Amphitheater Entertainment. Page 15 of
the Vista Site Assessment Report shows that inert material is
believed to be buried at this site.
13) On site wells at 2932 Gibbon Road consisting of nine monitoring
wells and four recovery wells owned by the Unocal Corporation.
These wells are shown in the site maps contained in Figure # 2 of
the variance request.
14) _An abandoned on-site water well at the southeast corner of 2932
Gibbon Road. The Unocal Corporation has reported that this well
has been filled with grout.
15) One off-site monitoring well at Durane Gas Company and another
monitoring well at the Handy Pantry.
16) An on-site septic tank located at the northeast corner of the former
Unocal Corporation property at 2932 Gibbon Road.
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17) Gibbon Road (a public roadway);
18) Derita Road (a public roadway);
19) Nevin Road (a public roadway);
20) A sewer line that runs along Nevin Road; and
21) A Southern Railroad Line that is 300 to 400 feet east-northeast of the
site. This railroad line runs a northwest to southwest direction.
Rule .0113{c}(3): Description of the proposed area for which the variance is requested:
Maps of the area are shown in Figures # 1 through # 4 and Appendix 111
and IV of the report titled "Variance Request Incident No. 3751 Unocal
Corporation Former Unocal Facility# 9342-811 Derita. North Carolina S&ME
Project No. 1354-92-667 (lune 1996)". A map identifying county parcel numbers
is contained in Figure # 4. Prior to cleanup, the area of the release was in the
shape of an ellipse and was estimated to be approximately 340 feet in diameter at
it's longest axis and 205 feet in diameter at it's shortest axis. The plume of
dissolved gasoline that came from this area of BTEX contamination was found
near the underground storage tank pit area around Monitoring Wells 3, 9, and
10. These wells are roughly located north and northwest of the tank pit area.
This plume was estimated to have covered an area of approximately 167,199
square feet (3.84 acres) prior to the implementation of corrective actions by the
Unocal Company (See Figure # 8 of Appendix 11).
The plume at 2932 Gibbon Road that Unocal is responsible for extends to
the southeast from the property going beneath Gibbon Road. The company asserts
that this plume did not extend as far as Monitoring Well 6 at the Handy Pantry
(Mecklenburg County Parcel Number 045-143-94). The furthest extent of this
plume to the northeast included a portion of the property owned by the Durane
Gas Company (Mecklenburg County Parcel Number 043-026-29). It is estimated
that the plume was beneath approximately 1,600 square feet of land on this
adjacent property. It is not believed that this plume extended as far as Monitoring
Well 15 on the Durane Gas Company land. The remainder of the plume was
found to cover most of the former Unocal Corporation site at 2932 Gibbon Road.
No other adjacent properties are known to have been impacted by this release
identified as Groundwater Incident Number 3751.
This variance is for all the land entirely within the property boundaries of
2932 Gibbon Road that was formerly owned by the Unocal Corporation. The
groundwater that was impacted by the release is located in the original pump
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island area and service station when Unocal owned the site. These structures have
since been removed from the property. Because groundwater monitoring results
do not show that contaminants from Unocal's release at 2932 Gibbon Road have
migrated at concentrations in exceedence of detectable limits, this variance
request does not include any land adjacent to the property at 2932 Gibbon Road.
If at any time monitoring reveals that concentrations of substances exceed the
Groundwater Quality Standards in 15A NCAC 2L .0202 on adjacent properties
and it could be determined that the Unocal Corporation is responsible for the
contamination, the Division could still require the Unocal Corporation bring these
concentration levels in compliance with the standards in 15A NCAC 2L .0202. A
variance granted by the Environmental Management Commission does not exempt
the Unocal Corporation from being held jointly or severally responsible for
cleanup.
Rule .0113(c){4l: Supporting information to establish that the variance will not endanger
the public health and safety ... :
Part of the variance concerns Groundwater Quality Standards shown in
15A NCAC 2L. 0202 and has been requested for Benzene, Ethylbenzene, Toluene,
Xylene (-o,-m, and p), Methyl Tert-Butyl Ether (MTBE), Naphthalene, lsopropyl
Ether, Ethylene Dibromide, 1,2-Dichloroethane, bis(2-ethlylhexyl)phthalate
{DEHP}, Chloroform, Methylene Chloride, 1-Methyl-Naphthalene, 2-Methyl-
Naphthalene, Tetrachloroethylene, Methylene Chloride, and Phenol. In order to
assess health impacts, monitoring wells were sampled at or near this site to assess
the extent of contamination and concentration levels of substances.
Concentrations of substances in recovery wells were also examined to determine
the effectiveness of the soil vapor extraction and air sparging cleanup systems at
removing these chemicals. In addition, concentrations of substances at the active
and inactive drinking water wells on adjacent properties were examined to
determine if the migration of contaminants is a significant exposure pathway.
Groundwater monitoring data from the Unocal Corporation indicates that
substances released by the Unocal Corporation at this site do not pose a hazard to
the public. A comprehensive listing of all monitoring results from monitoring
wells, recovery wells, and water supply wells are shown in the luly 29. 1996
Groundwater Data for Unocal-Derita. USEPA Method 601 and Method 602,
Method 625 and 504.1 were the analytical methods used for samples collected at
the Unocal Corporation site. USEPA Method 601 is used to assess the
concentration levels of purgeable halocarbons such as 1,2-Dichloroethane and
Chloroform. USEPA Method 602 is used to assess the concentration levels of
Benzene, Toluene, Ethylbenzene, Xylenes, and MTBE. USEPA Method 625 is used
to determine the concentrations of Base/Neutral Extractables such as Bis(2-
ethylhexyl)phthalate {also known as Di(2-ethlyhexyl)phthalate (DEHP)}. USEPA
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Method 504.1 is used to determine the concentration level of Ethylene Dibromide.
Sampling and analysis of on-site monitoring wells at 2932 Gibbon Road
have been conducted since March 4, 1992. A total of eighteen different sampling
events occurred from 1992 through 1996 at fourteen monitoring wells located at
or near the site. A total of eight different sampling events occurred at the deepest
well known as Monitoring Well 12 from March 4, 1992 through October 28,
1996. Except for Monitoring Well 12, the last sampling and analysis of all
remaining monitoring wells occurred on July 29, 1996. In response to concerns
raised by the Division of Epidemiology on August 12, 1996, the Unocal
Corporation conducted additional cleanup of groundwater at this well. This
cleanup was completed on October 18, 1996 and an additional groundwater
sample was taken on October 28, 1996.
As previously stated the highest concentrations of substances that appeared
in monitoring wells occurred between March 4, 1993 and August 18, 1995.
Since cleanup began on July 16, 1993 concentration levels of substances have
been significantly reduced over time. Upward "rebounding" of concentrations
above the Groundwater Quality Standards in 15A NCAC 2L .0202 has been noted
for some of these monitoring wells. With the exception of two on-site monitoring
wells, the most recent groundwater analysis has shown that concentrations of
substances in monitoring wells have been reduced below detectable limits. The
last semi-annual monitoring event that the Groundwater Section has on record
occurred on July 29, 1996. With respect to on-site monitoring wells, only
Monitoring Well 12 (MW-12) and Monitoring Well 13 (MW-13) had
concentrations of substances in exceedence of the Groundwater Quality
Standards in 15A NCAC 2L .0202. The analysis of samples from the remaining on-
site monitoring wells showed concentrations below detectable .limits. During the
July 29, 1996 semi-annual groundwater monitoring event Benzene appeared in
Monitoring Well 12 at a concentration of 3.34 x 10·3 milligrams per liter (mg/L) or
3.34 micrograms per Liter (ug/L). The Groundwater Quality Standard for
Benzene is 1 x 10-3 milligrams per Liter (mg/L) or 1.0 micrograms per Liter. 1,2-
Dichloroethane was also found in this well at 2.48 x 10-2 milligrams per liter
(mg/L) or 24.8 micrograms per Liter (ug/L). The Groundwater Quality Standard
for 1,2-Dichloroethane is 3.8 x 10-4 milligrams per Liter (mg/L) or 0.38 micrograms
per Liter. The July 29, 1996 semi-annual groundwater monitoring event also
revealed the presence of Bis(2-ethylhexyl)phthalate { also known as Di(2-
ethlyhexyl)phthalate (DEHP)} at a concentration of 0.742 milligrams per liter
(mg/L) or 742 micrograms per Liter (ug/L). The Groundwater Quality Standard
for DEHP is 0.003 milligrams per liter (mg/L) or 3.00 micrograms per Liter (ug/L).
On August 12, 1996 the Division of Epidemiology recommended that remediation
at this site continue until concentration levels of DEHP decreased below 0.060
milligrams per liter (mg/L) or 60 micrograms per Liter (ug/L). The company
initially believed that substances found at this site were from other possible
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sources located outside of the property boundaries of 2932 Gibbon Road.
Information in the Mooresville Regional Office showed that the consulting firm
that the Unocal Corporation had hired to conduct maintenance on the air
sparging system had not properly maintained coalescing filters for this equipment.
It must be noted that Bis(2-ethylhexyl)phthalate { also known as Di(2-
ethlyhexyl)phthalate (DEHP)} is a lubricating fluid used in vacuum pumps. Since
the coalescing filters were not properly maintained on the air sparging equipment,
it is possible that this fluid could have migrated out of the pumping system and
into Monitoring Well 12. In response to the August 12, 1996 comments by the
Division of Epidemiology and the September 23, 1996 request for additional
information from the Groundwater Section, the Unocal Corporation conducted
additional cleanup at this site. On October 18, 1996 the company pumped an
additional 300 gallons of water out of Monitoring Well 12. Special groundwater
sampling of Monitoring Well 12 on October 28, 1996 revealed that the
concentration of Di(2-ethlyhexyl)phthalate (DEHP) was below detectable limits.
No other substances appeared in the groundwater sample from Monitoring Well
12 using USEPA Method 625. During the July 29, 1996 monitoring event
Chloroform appeared in Monitoring Well 13 at a concentration of 2.17 x 10·3
milligrams per liter (mg/L) or 2.17 micrograms per Liter (ug/L). The Groundwater
Quality Standard for Chloroform is 1.9 x 104 milligrams per liter (mg/L) or 0.19
micrograms per Liter (ug/L). It must be noted that in previous analysis Chloroform
had appeared in this monitoring well only once on March 4, 1992 at a
concentration of 1.4 x 10·3 milligrams per liter (mg/L) or 1.4 micrograms per Liter
(ug/L).
The Unocal Corporation constructed Monitoring Well 6 located on off-site
property at 2947 Gibbon Road (Handy Pantry). Analysis of this downgraident
monitoring well began on March 4, 1993. Ten different sampling events have
occurred at this property. Except for Bis(2-ethylhexyl)phthalate {also known as
Di(2-ethlyhexyl)phthalate (DEHP)} no substances have ever appeared in this well
above Groundwater Quality Standards. The highest concentration of DEHP
appeared in this well at a concentration of 6.43 x 10-3 milligrams per liter (mg/L)
or 6.43 micrograms per Liter (ug/L). The Groundwater Quality Standard for DEHP
3.00 x 10-3 milligrams per liter (mg/L) or 3.00 micrograms per Liter (ug/L). This
substance has not appeared in the off-site well since December 1995. The only
substance found in Monitoring Well 6 during the July 29, 1996 monitoring event
was o-Dichlorobenzene (Orthodichlorobenzene) at a concentration barely above
detectible limits. Analysis of the upgraident monitoring well at the Durane Gas
Company (Monitoring Well 15) began on May 21, 1992. Eight different sampling
events occurred at this well. From May 21, 1992 through February 25, 1996
groundwater monitoring has been conducted by the Unocal Corporation at the
off-site Monitoring Well 15 (Durane Gas Company). Substances that have
appeared in this well have not exceeded Groundwater Quality Standards in 15A
NCAC 2L .0202. Sampling of this well could not be performed on July 29, 1996
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due to the discovery by the Unocal Corporation that this well has been removed.
It is believed that the owner of the Durane Gas Company property (3008 Gibbon
Road) removed this well.
From April 12, 1993 through July 29, 1996 analysis of samples from
recovery wells was also conducted by the Unocal Corporation. A minimum of
two sampling events and a maximum of sixteen sampling events have occurred at
the four recovery wells since April 1993. On July 29, 1996 Recovery Well 2 and
Recovery Well 4 had concentrations of substances below detectible limits. The
Unocal Corporation reported that it was not feasible to sample Recovery Well 1
and Recovery Well 3 due to the proximity of these wells to Monitoring Well 9 and
Monitoring Well 2 and effect that sampling of the recovery wells might have had
on the results from the monitoring wells.
According to Figure # 6 and Appendix IV of the report titled "Variance
Re q uest Incident No . 3751 Unocal Corporation Former Unocal Facilit y # 9342-
811 Derita. North Carolina S&ME Pro ject No . 1354-92-667 (l une 1996)" a
number of water wells are known to exist within ½ miles of 2932 Gibbon Road.
There are approximately 42 residential and businesses properties that obtain
drinking water from water supply wells. Six of these wells are known to be
inactive and property owners are obtaining water supply from the City of
Charlotte. All remaining properties in the area, listed in Appendix IV of the
variance request, obtain water supply from the City of Charlotte.
The nearest of these wells to 2932 Gibbon Road are four "inactive" water
supply wells and one water supply well in-use on adjacent properties near this site
that are potential receptors under 15A NCAC 2L .0102(19). These wells are
identified below as follows:
WELL ID NUMBER
OWNER ADDRESS IN VARIANCE RE Q UEST WELL STATUS
Gamble Pallet Company 3020 Gibbon Road GPW-1 or DW-2 Inactive
Durane Gas Company 3008 Gibbon Road WSW-0 Inactive
B & B Leather Company 6810 Nevin Road WSW-2 or DW-1 Active
T.B. Allen Incorporated 2929 Gibbon Road None Inactive
and 2923 Gibbon Road
Delta Unit Rebuilders 3001 Gibbon Road WSW-5 Inactive and
Disconnected
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In Table# 1 of the luly 29. 1996 Groundwater Data for Unocal-Derita the
company reports that Well WSW-5 (Delta Unit Rebuilders) was disconnected as
early as March 11, 1994 and has been replaced by city water. Another water
supply well once existed at 2932 Gibbon Road when it was owned by the Unocal
Corporation. On November 17, 1992 this well known as WSW-3 was closed
pursuant to 15A NCAC 2C .0100 with grout cement.
From April 7, 1993 through July 29, 1996 sampling was conducted at the
four inactive wells and the B & B Leather Company Well that is still in use to
determine the impact the remaining substances from 2932 Gibbon Road may have
on these receptors. Except for the Gamble Pallet Company Well (referred to in
the variance request as GPW-1 or DW-1) concentrations of substances in area
drinking water wells were found below detectable limits since sampling began on
March 7, 1993. The only substance ever found in the Gamble Pallet Company
Well was Tetrachloroethene (Perchloroethylene). The highest concentration of
this substance was 7.51 x 10·3 milligrams per liter (mg/L) or 7.51 micrograms per
Liter (ug/L) on February 25, 1996. The Groundwater Quality Standard for
Tetrachloroethene is 7.0 x 10-4 milligrams per liter (mg/L) or 0.7 micrograms per
Liter (ug/L). The semi-annual monitoring event on July 29, 1996 showed that the
concentration of this substance at 2.86 x 10·3 milligrams per liter (mg/L) or 2.86
micrograms per Liter (ug/L). Prior to these monitoring events Tetrachloroethene
was never identified in this inactive drinking water well as shown in Table# 1 of
the July 29. 1996 Groundwater Data for Unocal-Derita. According to Page 18 of
the report titled "Variance Request Incident No. 3751 Unocal Corporation
Former Unocal Facility # 9342-811 Derita. North Carolina S&ME Project No.
1354-92-667 (lune 1996)" this inactive drinking water well is located
approximately 425 feet northwest of the site. Figure 4 of the variance request
shows this well to be located cross gradient from the direction of groundwater
flow through the former Unocal site at 2932 Gibbon Road. Page 17 of the
variance request states that the company does not believe that the
T etrachloroethene found in this well is related to the release of petroleum under
Groundwater Incident# 3751.
On Pages 17 through 19 the Unocal Corporation has calculated the time
periods it would take for various contaminants that have been found at this site to
impact the down-gradient receptors. These receptors include active and inactive
water supply wells and an unnamed creek. The concentration of contaminants in
groundwater is primarily influenced by the direction and rate of groundwater
flow. The estimated groundwater flow rate is contained in the site assessment and
corrective action plan submitted by the Unocal Corporation to the Mooresville
Regional Office. Based on this information and Figure 4 in Appendix 111 of the
variance request, the Unocal Oil Company asserts that groundwater in the area
flows from the site travels toward an unnamed creek 1,100 feet to the south-
southeast of the site which drains into an unnamed pond. Drainage in this area
generally occurs to the southeast toward Irwin Creek.
13
. '
ground surface. Groundwater contamination beneath 2932 Gibbon Road is too
deep within the subsurface to impact these lines.
According to the Unocal Corporation's environmental consultant there are
no known buildings with basements at the site or in the general area that could
serve as conduits for the buildup of explosive, flammable, or toxic vapors from
this site.
Rule .0113 (d(5): Su pp ortin g information to establish that re q uirements of the rule cannot
be achieved b y p rovidin g best available technology economicall y reasonable:
The part of the request that concerns variance to Corrective Action in 15A
NCAC 2L .0106(j) will allow the Unocal Corporation to discontinue Corrective
Action at this site. The company has submitted supporting information in the
report and other documents demonstrating that the continued application of BAT
will not result in significant long term remediation of the site to the Groundwater
Quality Standards contained in 15A NCAC 2L .0202. The is due to the high
probability that continued cleanup activities at the site will not significantly
reduce contaminant levels below Groundwater Quality Standards in 15A NCAC
2L .0202.
Since discovery of the release on January 14, 1988 the Unocal Corporation
has disposed of a total of 2,300 tons of petroleum contaminated soil during tank
closure. The soil vapor extraction system (SVE) operated for 7824 hours during
1993 and 1994. As shown in Chart# 1 under Table# 1 of the report titled
"Variance Re q uest Incident No. 3751 Unocal Cor poration Former Unocal Facility
# 9342-811 Derita . North Carolina S&ME Project No. 1354-92-667 (l une 1996)".,
the company has monitored Total Petroleum Hydrocarbons in soils at this site
using Organic Vapor Analysis (OVA) of the SVE air stream from June 16, 1993
through September 1, 1994. According to Page 8 of the variance request, by 1994
the SVE system was removing hydrocarbons at a rate equal to or less than one
part per million. On Page 9 of the variance request states that ''The SVE system
was deactivated since it was no longer considered beneficial or cost effective, as
virtually no hydrocarbons were being recovered by the vacuum.". Based on air
flow rates shown on Page 9 of the variance request, the total mass of vaporous
hydrocarbons recovered by the SVE system is estimated at 3,400 pounds which is
equivalent to 567 gallons of gasoline. From August 17, 1993 through March 20,·
1996 the air sparging system operated for approximately 17,500 hours. Page 26
of the report titled "Variance Re q uest Incident No. 3633 Unocal Cor p oration
Former Unocal Facilit y # 9342-209 4336 Park Road Charlotte. North Carolina
S&ME Pro iect No. 1354,-92-397 (November 1995 )" states that a total of $ 751,863
has been expended to remove tanks, conduct site assessments, and cleanup soils
this site. Appendix V of the variance request shows itemized invoices for the
15
costs associated with remediation at 2932 Gibbon Road. Page 26 also shows that
this site was determined as "ineligible" to received reimbursements from the
Leaking Petroleum Underground Storage Tank Fund by the Division for cleanup of
this release. The Unocal Corporation has incurred the entire cost of cleanup of
this site.
Groundwater analysis of samples from all monitoring wells showed
significant reductions in the concentrations of substances from March 4, 1992
through October 29, 1996. Soil vapor extraction and air sparging were used to
reduce the concentrations of petroleum hydrocarbons in soils at this site from
June 16, 1993 through March 20, 1996. These technologies were implemented as
a means of cleaning up soils, prevent the migration of contaminants in soils into
groundwater, and inhibit the further degradation of groundwater at this site.
Groundwater monitoring up through the February 25, 1996 sampling event
showed reductions in the concentrations of substances in the groundwater. Since
that time analysis of samples from groundwater monitoring wells have not
demonstrated a significant reduction in contaminant concentrations as shown in
luly 29. 1996 Groundwater Data for Unocal-Derita. Results from the July 29,
1996 groundwater monitoring event demonstrates that a "rebounding" of
concentrations has occurred at this site for certain substances such that levels
exceed that Groundwater Quality Standards in 15A NCAC 2L .0202. On July 29,
1997 concentrations of Benzene, lsopropyl Ether, 1,2-Dichloroethane, and Bis(2-
ethylhexyl)phthalate {also known as Di(2-ethlyhexyl)phthalate (DEHP)} were
observed in Monitoring Well 12. It must be noted that during the time the soil
vapor extraction and air sparging technologies were in operation from June 1993
through March 1996, the concentrations of Benzene, lsopropyl Ether, and 1,2-
Dichloroethane remained below the 15A NCAC 2L .0202 Groundwater Quality
Standards or detectible limits. It is important to note that the DEHP concentration
in this well, which first appeared on August 18, 1995, was not reduced below
detectable limits until the removal of 300 gallons of groundwater via direct
pumping of Monitoring Well 12 on October 18, 1996. Chloroform appeared in
Monitoring Well 13 on July 29, 1996 above Groundwater Quality Standards in
15A NCAC 2L .0202. While cleanup technologies were in operation this
substance had never been identified in this monitoring well during seven previous
groundwater sampling events. This monitoring well is located at the northwest
corner of the property. Figure# 8 of Appendix II of the report titled "Variance
Request Incident No. 3751 Unocal Corporation Former Unocal Facility# 9342-
811 Derita. North Carolina S&ME Project No. 1354-92-667 (June 1996)" shows
that the plume of substances never extended as far as Monitoring Well 13.
In order to demonstrate that the requirements of the rule cannot be
achieved using best available technology, title 15A NCAC 2L .0113(c)(5) requires
that specific technology considered be identified, the costs of implementing the
technology be shown, and the impacts of the costs on the applicant be provided.
On August 18, 1997 the Groundwater Section staff discussed the potential costs
16
associated with continued cleanup of this site with staff from the Unocal
Corporation's environmental consultant S &ME Incorporated, if the variance were
not granted by the Environmental Management Commission. Mr. Stewart Hines
of S & ME Incorporated stated that he has estimated the cost of continuing to
operate the soil vapor extraction and air sparging cleanup systems to be
approximately$ 20,000 per year. This cost estimate includes the costs of
obtaining air quality permits to control emissions of volatile organic compounds
from the operation of this groundwater cleanup system. The Unocal Corporation
believes that the low residual concentrations of substances in groundwater and
soils at the site, the lack of any impacts on water supply wells, and the lack of any
human receptors does not warrant the additional expense of continuing
remediation with soil vapor extraction and air sparging.
The Unocal Corporation examined the use of in-situ or enhanced
bioremediation for this site. In-situ or enhanced bioremediation relies on the
introduction of nutrients and oxygen to groundwater to assist in supporting the
development of a population of microorganisms capable of breaking down
substances into harmless chemicals such that concentrations of substances are
reduced below the 15A NCAC 2L .0202 Groundwater Quality Standards. It must
be noted that the implementation of a cleanup system that relies on in-situ
bioremediation will not remediate concentrations of certain substances that have
been found historically or are present at this site which do not readily degrade
under anaerobic and aerobic conditions. Substances have been found at 2932
Gibbon Road that are not likely to degrade if a cleanup plan relying on in-situ
bioremediation were implemented at this site. These substances are chlorinated
compounds (1,2-Dichloroethane and lsopropyl Ether) and semi-volatiles (DEHP, 1-
Methyl-Naphthalene, and 2-Methyl-Naphthalene). The Unocal Corporation has
submitted information on Pages 20 through 23, and in Appendix VI supporting
their view that conditions at this site are such that the life and growth of
indigenous populations of microbes that may exist in the subsurface will be
sustained. The company believes that "intrinsic bioremediation" is already
occurring at this site for those substances that are readily degradable. Mr.
Stewart Hines of S & ME Incorporated has informed staff that in-situ or enhanced
bioremediation will require the company to expend an additional $ 10,000 to $
15,000 per year to implemented this technology at this site. This cost includes the
costs to meet the permitting requirements for injection wells in 15A NCAC 2C
.0200 to introduce nutrients and oxygen into the subsurface. It is not cost
effective to use in-situ bioremediation at a site where natural conditions in the
subsurface are capable of supporting viable microbial populations. The Unocal
Corporation did not identify any technology, other than those that have been in
use at this site or discussed in this variance, that would meet the requirements of
15A NCAC 2L .0106(j) as "best available technology".
17
.. . •.
Rule .0113(c )(6): Su pportin g information to establish that com p liance would p roduce
serious financial hardshi p on the a pp licant:
The Unocal Corporation has submitted information showing that
compliance with the rules will result in a serious financial hardship. Page 26 of
the report titled "Variance Re quest Incident No. 3751 Unocal Cor poration
Former Unocal Facilit y # 9342-811 Derita , North Carolina S&ME Pro ject No.
1354-92-667 (l une 1996)" shows that the Unocal Corporation has demonstrated
that the continued application of best available technology to this location would
be a prohibitively expensive method of remediating groundwater contamination.
The report states on Page 26 that "As you are aware Unocal sold this site in 1987
and has not made any income on this site since then. It has been a serious
financial hardship on Unocal for the last 9 years.". Groundwater Section staff
have examined the state trust fund status of this site and have verified that no
reimbursement through the Commercial Underground Storage Tank Trust Fund
has been granted to the Unocal Corporation for cleanup of this site. The Unocal
Corporation has thus far spent $ 751,863 to cleanup this site. In Appendix V of
the variance request Mr. Wayne Holt, Staff Engineer for the Unocal Corporation,
asserts that the company has " ... employed two of the most well accepted best
available technologies for clean up of this site". Allowing the persistence of low
levels of contaminants in groundwaters and soils that, after approximately 7 years
of applying best available technologies, have asymptotically approached the
Groundwater Quality Standards in 15A NCAC 2L .0106 through a variance is a
prudent means of addressing Unocal's release at this site. It is no less effective a
means of addressing residual concentrations of substances at this site than
continuing the use of soil vapor extraction with air sparging and is less expensive.
On the September 23, 1996 the Mooresville Regional Office completed it's
technical review of this variance request. A comment made by the regional office
in the September 23, 1996 memorandum states that " ... a CAP (Corrective Action
Plan) in accordance with 15A NCAC 2L .0106(k)(I) and/or (m) does not appear to
be an option at the Unocal site. ".
Rule .0113(d(7): Su pp ortin g information that com p liance would p roduce serious
financial hardshi p without eq ual or greater p ublic benefit:
The company has submitted information in the request demonstrating that
the environment, safety and public health would not be impacted by this variance.
The Groundwater Section believes that the public will not benefit from
18
. .
compelling the Unocal Corporation to continue remediating this site using soil
vapor extraction technology, air sparging, the other alternative discussed, or any
combination of these.
Rule .0113 (c )(8 ): "A copy of an y Special Order ... ":
No Special Order by Consent has been issued for this site.
Rule .0113 (c)(9): "A list of names and addresses of p ro p erty owners ... ":
The property owners within the proposed area of the variance are shown on
Figure 4 of the report titled "Variance Re g uest Incident No. 3751 Unocal Corp oration
Former Unocal Facility # 9342-811 Derita . North Carolina S&ME Pro ject No. 1354-92-
667 (l une 1996)". This listing includes Dwyers Auto Repair, B&B Leather, Players
Sporting Goods and Johnny's Furniture, property owned by Ronald V. Sorrells and wife
Marilu Rea, the Atlantic Steel Supply Company, two properties owned by the South
Central Oil Company including the Handy Pantry, T.B. Allen Enterprises Incorporated,
Delta Unit Rebuilders, property owned by Ronald W. Patten, Leo J. Monin, and wives,
Durane Gas Company, the Gamble Pallet Company, Greasy's Truck Repair Incorporated,
a single family home owned by the Department of Brotherhood Pensions and Ministerial
Relief, the North Carolina Department of Transportation, and Southern Railroad. Of the
42 businesses and residences in the general area around 2932 Gibbon Road that obtain
drinking water from water wells, five of these wells are located on the nearby properties
discussed. Title 15A NCAC 2L .0113(e)(E) requires that notification of a public hearing
on this variance be given to the owner or owners of these adjacent properties "at least
30 days prior to the date of the hearing".
It is the recommendation of the Groundwater Section that the subject variance
request to Corrective Action requirements of 1 SA NCAC 2L .0106(j) and Groundwater
Quality Standards contained in 1 SA NCAC 2L .0202 proceed to public notice in
accordance with 1 SA NCAC 2L .0113(e). On February 7, 1997 the Division of
Epidemiology completed their review of the risk assessment methodology for this site and
recommended that this variance be granted for the Unocal Corporation at 2932 Gibbon
Road in Derita, North Carolina. Upon your concurrence with our recommendation, the
Groundwater Section will proceed with the preparation of the required public notice and
19
hearing. Upon completing of the requirements of 1 SA NCAC 2L .0113(d -f), this request
will proceed to the Environmental Management Commission Groundwater Committee,
and, if approved, this request will proceed to the Environmental Management Commission
for final action as specified in 1 SA NCAC 2L .0113(g). If there are any questions regarding
this matter or if any additional information is needed, please let me know.
ATTACHMENTS:
cc: Groundwater Section Assistant Chiefs
Mooresville Regional Groundwater Supervisor
Dr. Ken Rudo
David Hance
20
Author: David Hance at NRGWS0lP
iDate: 8/19/97 5:35 PM
Priority: Urgent
TO: Sue Crow
CC: David Hance
Subject: re: Submission for Reimbursement from the UST Trust Funds
------------------------------------Message Contents------------------------~-----------
Sue,
I am working on a variance for a Unocal Corporation site in Derita,
North Carolina. This site is known as Groundwater Incident Number 3751
and came out of the Mooresville Regional Office. Do we have a record
of any record of claims activity on this site out of the State Trust
funds????
Please e-mail a response to me.
David Hance
GW-Planning Branch
MONITOR WELL I DATI.
~AMETHoo=---uw-12 3/4(9:.-~
--· 4/9/9:1
11/3/94 ---· 3/1/9!; --8/18/95 ~ ---
---12/1/~~
7/29/93 ------
MW-13 3/4/9;1
4/8/9:1 ---8/10/9 3 ---8/13/9) ---10/5/91 ---11/4/9] ---12/8/93 ------1/12/94_
2/3/9•1 ---· 5/3/9•1 ---7/8/9•1 ---8/11/94 ---11/3/94 ---------3/1/9!,-------8/18/9~
11/30/!15 --2/25/95 ---
7/29/9~
~-14 3/4/9'.· -----4/9/9:1 ------8/13/!H---------;ois7ei-----11/4/93 ---12/8/9 l ----1/12/9-(
2/3/9( -----5/3/9~·-·
7/8/9~ ---8/11/94 -11/3/9-i ---3/1/9( ---· 8/18/9:,·-----11/30/&~----2/25/9<,
7/29/91i
i=a==-=--MW ~ 5/21/9:i ---::-~ -~/93
_,7 ~, 8/10/9:l
[~ r,,,,_ 2/3/94. ,, I 8/11/9•1-
l~of 11130/95
2/25/9il
7/29/9()
==i'fw-1 4112/9:l
B/13/9:i
8/23/9:1 ----· 8/30/9:l ----8/30/9:i ---4/24/91,. ---· ...J/~~~fl ----· ---
L.J L..ci L....J L........Ji Lt Lffl Lr
~ 5 Y~~'7 m ~ ~ct-.i~ /'11t
TABLE 1 :To1"2)/t, /ttj~J -HISTORICAL GROUl'lllWATER QUALITY DATA
FORMER UNOCAL FACILll'f #9342-811
2932 GIBBON ROAD
DERITA, NC
BENZENE TOI.IJENE ETHYL-TOTA TOTAL MfflE IPE BJB
BENZENE XYLENES
~ BJEX
602 602 eoCC:002 602 602 602 504.1
,=3000 265 665 1530 5460 N.J N> 'f,,IA
2400 BQL BQL 680 3080 BQL 140 3-.3--
-<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <1 NA
<0.5 <0.5 <0.5 <0.5 --<o:5 <0.5 <1 <0.01
1.19 <0.5 <0.5 <0.5 1.19 <0.5 <1 <0.01
0.784 <0.5 <0.5 <0.5 0 .784 2.32 <1 <0.01
3.34 1.84 <0.5 <0.5 5.17 70.8 2.85 <0.01
BQL BQL N) ND BOL BQL N) 1.4
BQL BOL BQL BQL BQL BQL BQL BQL
BQL BQL BQL BQL BQL BQL BQL NA
NA NA NA NA NA NA NA BQL
<0.5 <0.5 <0.5 <0.5 <0.5 NA NA NA
<0.5 <0.5 <0.5' <0.5 <·o .5 NA NA NA
<0.3 0 .54 <0.3 0.85 <2 NA NA NA
<0.5 <0.5 <0.5 <0.5 <2 NA NA NA
<5 <5 <5 <5 <20 BQL BQL NA
<0.5 <0.5 <0.5 0 .67 <2 NA NA NA
<0.5 <0.5 <0.5 <0.5 <2 NA NA NA
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.005
<0.5 <0.5 <0.5 <0.5 <0.5 1.4 NA NA
<0.5 0.852 <0.5 <0 .5 0.852 2 .49 <1 <0.01
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <1 <0.01
<0.5 <0.5 <0.5 <0.5 <0.5 1.96 <1 <0.01
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <1 <0.01
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <1 <0 .01
3200 11 .000 3700 13 ,200 31 ~ N) N) NA~
510 i~ ~490 3100 5400 190 120 0 .12
980 2300 1700 7800 12,780 470 370 0.068
1400 4800 -1600 94 ~ --;noo N-A---~ NA
900 3400 900 6500 11700 NA NA NA
310 940 240 1900 3390 NA NA NA
210 720 210 2600 3740 NA NA NA
97 350 75 950 1472 BQL BQL NA
6 .1 37 11 250 304.1 NA NA NA
13 62 16 240 331 NA NA NA
5 .14 40.7 10.9 306 362 <0.5 <0.5 <0.005
<0.5 1.45 1.11 22.5 25 2.7 NA NA
"<0.5 0 .544 <0.5 0527 1.07 3 .79 <1 ~-1 -----·-<0.5 <0.5 <0.5 0 .521 0.521 <0 .5 <1 <0.01
<0.5 <0 .5 <0.5 <0.5 <0.5 <0 .5 <1 <0.01
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <1 <0.01
<1 <1 <1 <1 <1 <1 <2 <0.01
ND ND ND ND ND ~ ~ NA
BQL 1 BQL 4 5 BQL BQL BQL
BQL BQL BQL BQL BQL BQL BQL BQL
BQL BQL BQL BQL BQL BQL BQL NA
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.005
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <1 <0.01
<0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <1 <0 .01
WELL COULD NOT BE FOU!IO POSSIBLY REMOVED BY NEW PROPERTY OWNER
B 11 2 21 42 -BQL 5 BQL
BQL BQL BQL BQL BQL 25 ,000 BQL 0 .042
11 BQL BQL 130 141 NA NA NA
540 69 30 500 1139 NA NA NA
WELL cm VER TED T( A VACUUh WELL AFTER SAMPLI NG GROU~ )WATER
<0.5 <0.5 <0.5 <0.5 <0.5 24 .1 <1 <0.01
~hL NOTSIWPLED DUE TO CLOSE PROXIMITY T O -~~-9
L I h;.;...
---j PURGEABLE BASE/NEUlllAL
..
llALOCARBONS EXffiACT ABLES
601 == -=-625 ---65 NA
330 NA
BQL 5~11
BOL NA
BQL 2700
BQL 578 -Bis(2-othylhe~l)bhlhalal e
24.8 -1 2-dichloroethane 742 -b isf2-ethvlhexyl}phthalate
3 .19 -d1 -n-b !!!'llohthalate
1.4 NA
BQL NA
BQL BQL
NA NA
NA NA
NA NA
NA NA
NA NA
BQL NA
NA NA
NA NA
BQL BQL
NA NA
BQL NA
BQL 9
BQL BQL
<0.5-5 NA
2 .17 -ch!orofonn <1 r,o NA
BQL NA
BQL 250
NA NA
NA NA
NA NA
NA NA
BQL NA
NA NA
NA NA
BQL 56.08
NA NA
BQL NA
SOL BQL
BQL BQL
<0.5-5 NA
<2-1_0 12.2 -di-n-butvlohthalate
N) NA
BQL NA
BQL BQL
BQL NA
BQL 138
BQL BQL
<0.5-5 NA
3 NA
7 BQL
NA NA
NA NA
<0.5-5 NA
SITE ASSESSMENT REPORT
PROPERTY CLIENT
INFORMATION INFORMATION
Project Name/Ref#: 19042 STEWART HINES
FORMER UNOCAL CORPORATION GAS STATION SME INC-CHARLOTTE
2932 GIBBON RD 9751 SOUTHERN PINE BLVD
DERITA, NC 28269 CHARLOTTE, NC 28273
Cross Street: NEVIN RD
Latitude/Longitude: ( 35.300497, 80.806328 )
Site Distribution Summary within 1/8 118 to 114 to 1l2to
mile 1/4 mile 112 mile 1 mile
Agency I Database -Type of Records
A) Databases searched to 1 mile:
US EPA NPL National Priority List 0 0 0 0
US EPA CORRACTS RCRA Corrective Actions and
(TSO) associated TSD 0 0 0 0
STATE SPL State equivalent priority list -o-0 0 -o-
STATE SCL State equivalent CERCLIS list --ir---0 -o-0
B) Databases searched to 1/2 mile:
US EPA CERCLIS/ Sites currently or formerly under review
NFRAP by US EPA 0 0 0 -
US EPA TSD RCRA permitted treatment, storage,
disposal facilities 0 0 0 -
STATE LUST -Leaking Underground Storage Tanks , 0 1 .
STATE SWLF Permitted as solid waste landfills,
incinerators, or transfer stations 0 0 0 .
C) Databases searched to 1/4 mile:
STATE UST Registered underground storage tanks 3 0 . -
D) Databases searched to 1/8 mile:
US EPA ERNS Emergency Response Notification
System of spills 0 -. -
US EPA LG GEN RCRA registered large generators of
hazardous waste 0 . . .
US EPA SM GEN RCRA registered small generators of
hazardous waste 1 . . . --
~ For more information call VISTA Information Solutions, Inc. at 1 -800 -767 -0403.
Report ID: 140064-001 Date of Report: July 30, 1997
Version 2.5 Page #1
..
• . I
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James 8. Hunt, Jr., Governor
Jonathan 8. Howes, Secretary
A. Preston Howard, Jr., P.E., Director
MEMORANDUM:
January 21, 1997
TO: Dr. Ken Rudo, Ph.D, Toxicologist,
Environmental Epidemiology Section
FROM: ArthurMouberry, P.E., Chief 1',J/
Groundwater Section ~
A.TA
DEHNR
SUBJECT: Follow-up Information and Request for Further Review on the Unocal
Corporation Request for Variance from 15A NCAC 21 .0202 Groundwater
Quality Standards for Property at 2930 Gibbon Road in Derita, North Carolina
(DEM Groµndwater Incident Number 3751 }.
On July 9, 1996 it was requested that you review the risk assessment methodology for
a proposed variance at a Unocal Corporation site in Derita, North Carolina. This site is located
on 2930 Gibbon Road in Derita, NC (GW Incident Number 3751). On August 12, 1996 the
Division of Epidemiology responded with a letter stating that they could not support a variance at
this site. You will recall that the Division was concerned with the potential health impacts of
0.742 milligrams per liter of Bis(2-ethylhexyl)phthalate found on July 29, 1996 in the deep
monitoring well at this site.
Since that time the company conducted additional cleanup of the deep well via vacuum
pump technology. Approximately 300 additional gallons of groundwater was removed from this
site. A memorandum dated November 8, 1996 shows the concentrations of Method 625
chemicals, including Bis(2-ethylhexyl)phthalate, below the practical quantitiation limits.
Groundwater Section. Voice 919-733-3221 FAX [phone]
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
N(;C
·ee1.aa1ee
An Equal Opportuntty / Affimiative Action Employer
50% recycles/10% post-consumer paper
Attached is a copy of the November 8, 1996 monitoring results with other relevant
correspondence. Please review the.attached laboratory results to determine if this new
information will support a conclusion that a variance at this site will not adversely impact health.
If this request should proceed forward to public hearing or additional information is needed,
please send us a response. If possible, we would like to receive your response by February 4,
1997. If you have any questions, please contact David Hance at 715-6189 .
cc: Arthur Mouberry
Carl Bailey
Dr. Burrie Boshoff
David Hance
~ooresville Regional Groundwater Supervisor
Allen Schiff
Attached is a copy of the November 8, 1996 monitoring results with other relevant
correspondence. Please review the · attached laboratory results to determine if this new
information will support a conclusion that a variance at this site will not adversely impact health.
If this request should proceed forward to public hearing or additional information is needed,
please send us a response. If possible, we would like to receive your response by February 4,
1997. If you have any questions, please contact David Hance at 715-6189.
cc: Arthur Mouberry
Carl Bailey
Dr. Burrie Boshoff
David Hance
Mooresville Regional Groundwater Supervisor
Allen Schiff
.. ♦S&ME
November 8, 1996
Mr. Allen Schiff
North Carolina Department of
Environment, Health and Natural Resources
919 N. Main Street
Mooresville, NC 28115
RE: Method 625 Analyses for MW-12 Groundwater on 10/28/96
NCDEHNR Incident #3751, Priority Ranking 90/B
Unocal Corporation, Former Station #9342-811
2932 Gibbon Road, Derita, NC
S&ME Project No. 1354-92-667
Dear Mr. Schiff:
U). ~-
%
0 ...::: -w
-0 :::c -r;-?·
0 -
Cl n, -,,, -c;::O
:;o~
Or.-;
C-:z< om
..-;:C ----::D: rr,
--t::i::
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f1'1
~
S&ME, Inc., on behalf of Unocal Corporation, sampled groundwater from deep (fype 111)
bedrock monitor well MW-12 on October 28, 1996 after 8-hours of vacuum truck work on
October 18, 1996. Approximately 300 gallons were removed from MW-12 and properly
disposed by Enviroct,em of Apex, NC. The Flowers Chemical Laboratory (Certification
#296) revealed no Method 625 compounds above the North Carolina Practical
Quantitative Limit of 3 ug/L in groundwater sampled from MW-12. Therefore, please
proceed with review of the June 13, 1996 Variance Request, per your October 23, 1996
letter.
Additionally, all RegenesisrM magnesium peroxide socks have been removed from all five
monitor wells on-site, per your request. If you have any questions or need additional
information, please call. ·
Sincerely,
S&ME, Inc.
~
Stewart M. Hines, LG.
Senior Hydrogeologist
cc: Wayne Holt -Unocal Corporation
. David Hance-NCDEHNR, Raleigh Central Office
K:\. .. IHINES\1996\SCHIFF96.N0B
S&ME, Inc. 9751 Southern Pine Boulevard, Charlotte, North Carolina 28273, [phone], Fox [phone]
Mailing address: P.O. Dox 7668, Charlotte, North Carolina 28241-7668
.f
,JIUlt: UI l'JOITn ~arouna Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
A Preston Howard, Jr., P.E., Director
CERTIFIED MA IL P 281 578 544
RETURN ·RECEIPT REQUESTED
Mr. Stewart M. Hines
S&ME Incorporated
9751 Southern Pines Blvd.,
Charlotte, NC 28273
October 23, 1996
A.TA
D E HNR
I
I
J
I
.Subject: Request for Variance Under 15A NCAC 2L .0113 for the Unocal
Corporation at 2932 Gibbon Road in Derita, North Carolina
(Groundwater Incident# 3751)
Dear Mr. Hines:
The Division of Water Quality has reviewed the information submitted in the variance
request received on June 13, 1996. The information contained in your request does not meet the
requirements for a variance application filed under 15A NCAC 2L .0113 for the following
reasons:
1) The supporting information to establish that the variance "will not endanger
the public health .and safety, ...... " was incomplete. The request needs to
demonstrate that concentrations of substances have been sufficiently reduced or
removed from the site such that groundwater can be used in accordance with it's
best use. The classifications in 15A NCAC 2L .0201 establish by rule that the best
use of groundwater in this area is as a source of drinking water. A groundwater
sample from the bedrock monitoring well taken on August 18, 1995 revealed bis(2-
ethylhexyl)phthalate at a concentration of 2,700 ppb (2. 7 milligrams per liter).
Groundwater Section.
1
Voice 919-733-3221 FAX [phone]
(
P.O. Box 29578. Raleigh. North Carolina 27626-0578
2728 Capital Blvd.. Raleigh. North Carolina 27604
NOC
rem1-1tdiW
An Equal Opportunity/Affirmative Action Employer
50"/4. recycles/10% post-consumer paper
(
The Unocal Corporation has submitted information to the Mooresville Regional
Office indicating that the presence of this substance may be due to the unintentional
release of fluids from vacuum pumping equipment used to implement the corrective
action plan for this site. Between November 3, 1994 and August 18, 1995 the
Unocal Corporation terminated the contract of a firm that was responsible for
maintaining the condition of vacuum pumps and other remediation system
components due to poor performance. Part of the reason for the termination was
that the subcontractor was not performing any maintenance on coalescing filters
used in air sparging equipment. A fluid used in these vacuum pumps is bis(2-
ethylhexy l)phthalate. As of March 20, 1996 all soil cleanup activities ceased at
this site. On July 29, 1996 the concentration of bis(2-ethylhexyl)phthalate in the
bedrock monitoring well was reported to have been reduced to 742 ppb (0.742
milligrams per liter). It must be noted that information submitted by Unocal
Corporation shows that there are a number of properties near 2932 Gibbon Road
that use groundwater as a source of drinking water.
Based on the persistence of bis(2-ethylhexyl)phthalate at a concentration
above the level protective of human health, the possible release of this substance
into groundwater from cleanup equipment used by the company, and the continued
use of groundwater as drinking water supply, the Groundwater Section cannot
determine that the variance is complete for review by the Director in accordance
with 15A NCAC 2L .0113(d) and it cannot proceed to public notice, public
hearing, and final review by the Environmental Management Commission pursuant
to 15A NCAC 2L .0113.
In order to pursue a variance for Groundwater Incident Number 3751, the
Unocal Corporation must provide either of the following information in a variance
request:
a) A demonstration to the Groundwater Section that the concentration
of bis(2-ethylhexyl)phthalate at this site has been reduced, by the
implementation of the cleanup technology presently at the site or an
approved corrective action plan, such that it is below 60 ppb (0.060
milligrams per liter); or '
It is established, to the satisfaction of the Groundwater Section,
that the presence of bis(2-ethylhexyl)phthalate at this site is due to
another source of contamination that is located offsite from the
property at 2932 Gibbon Road in Derita, North Carolina.
The additional information in items # l(a) and/or # l(b) must be provided so that the
Groundwater Section can properly evaluate the variance request and verify to the Director
that it meets the requirements of 15A NCAC 2L .0113 (c). Once the Groundwater Section
2
deems a variance request has met these requirements, it can proceed to the Director for
-----. review in accordance with lSA NCAC 2L .0113 (d). For this reason the request is being • 1
.)
returned to you. If you wish to continue pursuing a variance to the Subchapter 2L rules you will
need to submit information that addresses items #l(a) and/or #l(b). On August 12, 1996 the
Division of Epidemiology completed it's review of the risk assessment methodology and health
impacts of residual concentrations for this variance request. Based on information in the June 13,
1996 variance request, the Division of Epidemiology reported that the remaining concentrations
of all substances, except for bis(2-ethylhexyl)phthalate, were sufficiently low such that they should
not pose any future health risks to residents living adjacent to this site that continue to use
groundwater as a drinking water source. If you have any questions concerning this letter, please
contact Mr. Allen Schiff, Mooresville Regional Office, Groundwater Section, at [phone].
Sincerely,
~,ny~~
Arthur Mouberry, P.E.,
Chief, Groundwater Section
APH/ AM./dah
cc: Arthur Mouberry
Carl Bailey
Burrie Boshoff
Mooresville Regional Groundwater Supervisor
David Hance
A. Wayne Holt (Unocal Corporation)
3
DIVISION OF WATER QUALITY
September 23, 1996
MEMORANDUM TO: Arthur Mouberry
FROM: Allen Schiff iLg
THROUGH:
SUBJECT:
Barbara Christian .lJc-
Review of Variance Request for
Former Unocal Facility No. 9342-811
2932 Gibbon Road
Priority Rank 90/B
Mecklenburg County, N.C.
Groundwater Incident No. 3751
--·--. _ _. ...
;_:,;7 _.,
Upon review of the June 1996 variance request, the
Groundwater Incident file for the subject site and Dr. Ken Rudo's
comments, the MRO offers the . following:
1. The petroleum contaminant plume appears to be almost
completely remediated except for Benzene(3.34ppb) and 1,2-
dichloroethane(24.Bppb) found in deep(bedrock) monitor well
MW-12 per the most recent sampling conducted July 29, 1996 .
Additionally, bis(2-ethylhexyl)phthalate(hereinafter bis2) was
found i~ MW-12 at a concentration of 742ppb.
2. Air sparging and SVE were utilized at the site to remediate
the petroleum plume that contained BTEX as high as 31,l00ppb
(MW-14), prior to CAP implementation, to BDL in the same well as
of the July 1996 sampling event.
3. Dr. Rudo indicates in his August 12, 1996, memo that he
cannot support the variance request due to the high level of bis2
found in MW-12. His rec'ommendation is further remediation of the
bis2 constituent. I offer the following items for consideration
with respect to Dr. Rudo's comments and Unocals options:
A. The existing air sparging/SVE system could not be utilized
to remediate the bis2 in MW -12 because it is a bedrock
well where uncontrolled sparging is not advisable. This
would require Unocal to implement a separate CAP system to
remediate the bis2.
B. Unocal has expended in excess of $751,863 at the site
that has previously been determined to not be reimbursable
from the STF. In addition, O&M costs for the existing
CAP system would total approximately $20,000 annually when
the system was in operation.
)
C. Since bis2 is not related to petroleum contamination, it
may have been introduced to MW-12 through the remediation
system. This statement can be supported by the following:
1. The remediation system utilized vacuum pumps and bis2
is a liquid used in vacuum pumps(see attached).
2. In the 11/3/94 sampling of MW-12, bis2 was found at
only Sppb but jumped to 2700ppb during an August 18,
1995 sampling. During this time period Unocal
utilized a separate consulting firm than S&ME to
perform O&M on the CAP system components. This
consulting firm was terminated by Unocal for
poor contract performance in part due to no maintenance
on the coaliscing filters for the sparging unit.
The MRO has requested additional information from
Unocal about the circumstances leading to the dismissal
of the consultant. The current level of bis2 was 742ppb
as of the July 29, 1996 sampling.
In light of Dr. Rudo's comments, the level of bis2 in
bedrock monitor well MW-12 and active water supply wells in the
area, the MRO finds that, at this time, a CAP in accordance with
15A NCAC 2L .0106(k), (1) and/or (m) does not appear to be an
option at the Unocal site. If the source of the bis2 could be
confirmed to have been introduced to MW-12 by the existing CAP
system, as indicated on page six of the variance request, then
the appropriate action would have to be taken. If on the other
hand it is determined that the bis2 is from an·offsite source,
then the variance could be approved based upon the contamination
that Unocal was responsible for.
If you should have any questions, I can be reached at (704)
663-1699 ext. 236.
Attachments
ajs
DIVISION OF WATER QUALITY
GROUNDWATER SECTION
August 19, 1996
MEMORANDUM:
TO:
FROM:
Barbara Christian, Regional Groundwater Hydrogeological Supervisor,
Mooresville Regional Office
Arthur Mou berry, P .E., Q
Chief, Groundwater Sectfr;
SUBJECT: Review of Comments from the Division of Epidemiology on the Request for
Variance from 1 SA NCAC 2L .0106 Corrective Action Plans and 1 SA NCAC
2L .0202 Groundwater Quality Standards by the Unocal Corporation for a Site
at 2930 Gibbon Road in Derita, North Carolina {DWQ Groundwater Incident
Number 3751 }.
You will recall that on July 9, 1996, the Mooresville Regional Office was requested
to review a variance for the Unocal Corporation site in Derita, North Carolina (DWQ
Groundwater Incident Number 3751). In the July 9, 1996 letter it was requested that this
variance be reviewed in light of the requirements contained in 1 SA NCAC 2L .0106 (k), (I)
and/or (m) and 1 SA NCAC 2L .0113(c)(1-9) and (d). In addition, we informed you that a
copy of this request was sent to Dr. Ken Rudo at the Division of Epidemiology for review
of the risk assessment methodology used by the company.
On August 12, 1996 Dr. Rudo informed that Groundwater Section that the Division
of Epidemiology cannot support a variance for this site at this time. Attached is a letter from
the ·Division of Epidemiology stating that the concentration of bis(2-ethylhexyl)phthatlate
found during routine monitoring on December 1, 1995 in monitoring well # 12 is not
protective of public health. It is Dr. Rudo's view that remediation at this site should continue
until levels have decreased below 60 micrograms per liter or 0.060 milligrams per liter.
I have been informed that due to the necessity for Mooresville Regional Office staff
to attend court on enforcement matters, the review of this variance request should be
delayed. Please included in your recommendations on this variance a discussion of this
comment from Dr. Rudo. If it is necessary to meet and discuss this issue with Dr. Rudo,
please feel free to contact me at [phone]. If possible, please return your
recommendation on this variance and your response to the August 12, 1996 memorandum
from Dr. Rudo to me by Tuesday September 23 , 1996.
ATTACHMENT:
cc: Carl Bailey
Burrie Boshoff
David Hance
Allen Schiff
~tote ot North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
AVA
A. Preston Howard, Jr., P.E., Director D E HNR
July 9, 1996
MEMORANDUM:
TO:
FROM:
Dr. Ken Rudo, Ph.D, Toxicologist,
Environmental Epidemiology Section
Arthur Mouberry, P. E. , Chief ,V /
Groundwater Section G/'
SUBJECT: The Unocal Corporation Request for Variance from
15A NCAC 2L .0202 Groundwater Quality Standards
for Property at 2930 Gibbon Road in Derita, North
Carolina (DEM Groundwater Incident Number 3751}.
Attached is a variance request on behalf of the Unocal Corporation from SM&E
--:-" Incorporated. The request is for a variance to groundwater standards for Benzene,
·-\) Ethylbenzene, Toluene, Xylene (-o,-m, and -p), Methyl Tert-Butyl Ether, lsopropyl Ether,
Ethylene Dibromide, 1,2-Dichloroethane, bis(2-ethylhexyl)phthalate, Naphthalene,
1-Methyl naphthalene, 2-Methyl naphthalene, T etrachloroethylene, Ch I oroform, Methylene
Chloride, and Phenol.
The request is for a site contaminated by a release of gasoline from an underground
storage tank. The area requested for variance is all the property at 2930 Gibbon Road
formerly owned by the Unocal Corporation. This property is presently owned by Frank
Dwyer of 2930 Gibbon Road, Derita, North Carolina. Since Unocal sold the property in
1987 this site has been used for an auto repair shop. According to information submitted
by the company, this facility is vyithin the Town of Derita in an area of mixed residential
and commercial development. Monitoring well data indicates contamination in excess of
groundwater standards as described by 1 SA NCAC 2L .0202.
Extensive efforts have been made by the company, over the last few years, to remove
and recover free product, remediate soil, prevent the contamination of groundwater, and
cleanup groundwater. The Unocal Corporation does not believe that any public: benefit can
be gained through continued groundwater remediation efforts.
Please review the attached report and provide the Groundwater Section with a
recommendation regarding this request. If possible, the Section would like to receive your
recommended response by August 6, 1996.
Groundwater Section, Nii 6'1
P.O . Box 29578, Raleigh, North Carolina 27626-0578 w.,., '-.;
2728 Capital Blvd., Raleigh, North Carolina 27604 < , • ~ • ·, •
Voice 919-733-3221 FAX [phone]SM
An Equal Opportunity/ Affirmative Action Employer
50% recycled/10% post-consumer paper
·•
Upon receiving your recommendation, the Section will forward a recommendation
to the Director of the Division of Environmental Management.
If you need additional assistance or information please call me at 733-3221.
cc: Carl Bailey
Dr. Burrie Boshoff
David Hance
Mooresville Regional Office Groundwater Supervisor
2
.. ♦S&ME
November 8, 1996
Mr. Allen Schiff
North Carolina Department of
Environment, Health and Natural Resources
919 N. Main Street
Mooresville, NC 28115
RE: Method 625 Analyses for MW-12 Groundwater on 10/28/96
NCDEHNR Incident #3751, Priority Ranking 90/8
Unocal Corporation, Former Station #9342-811
2932 Gibbon Road, Derita, NC
S&ME Project No. 1354-92-667
Dear Mr. Schiff:
\.0 .
O"\ .
z
0 <
c.,.)
-0 :x
~
C) -
0 rn ...,,. -~~
::ufT'; c-> Orr,
C-z-< om ..,,.c -:;-►.fTl -:r: ri-::0;5
(/"J
r,'1
0
S&ME, Inc., on behalf of Unocal Corporation, sampled groundwater from deep (Type 111)
bedrock monitor well MW-12 on October 28, 1996 after 8-hours of vacuum truck work on
October 18, 1996. Approximately 300 gallons were removed from MW-12 and properly
disposed by Enviroctiem of Apex, NC. The Flowers Chemical Laboratory (Certification
#296) revealed no Method 625 compounds above the North Carolina Practical
Quantitative Limit of 3 ug/L in groundwater sampled from MW-12. Therefore, please
proceed with review of the June 13, 1996 Variance Request, per your October 23, 1996
letter.
Additionally, all Regenesis TM magnesium peroxide socks have been removed from all five
monitor wells on-site, per your request. If you have any questions or need additional
information, please call. ·
Sincerely,
S&ME, Inc.
Stewart M. Hines, LG.
Senior Hydrogeologist
cc: Wayne Holt -Unocal Corporation
. David Hance-NCDEHNR, Raleigh Central Office
K:\...\HINES\1996\SCHIFF96.N0B
S&Mf., Inc. 9751 Southern Pine 13oulevard, aiartotte, North Carolina 28273, [phone], Fax [phone]
Mailing address: P.O. Box 7668, O,artotte, North Carolina 28241-7668
C. Since bis2 is not related to petroleum contamination, it
may have been introduced to MW-12 through the remediation
system. This statement can be supported by the following:
1. The remediation system utilized vacuum pumps and bis2
is a liquid used in vacuum pumps(see attached).
2. In the 11/3/94 sampling of MW-12, bis2 was found at
only Sppb but jumped to 2700ppb during an August 18,
1995 sampling. During this time period Unocal
utilized a separate consulting firm than S&ME to
perform O&M on the CAP system components. This
consulting firm was terminated by Unocal for
poor contract performance in part due to no maintenance
on the coaliscing filters for the sparging unit.
The MRO has requested additional information from
Unocal about the circumstances leading to the dismissal
of the consultant. The current level of bis2 was 742ppb
as of the July 29, 1996 sampling.
In light of Dr. Rudo's comments, the level of bis2 in
bedrock monitor well MW-12 and active water supply wells in the
area, the MRO finds that, at this time, a CAP in accordance with
15A NCAC 2L .0106(k), (1) and/or (m) does not appear to be an
option at the Unocal site. If the source of the bis2 could be
confirmed to have been introduced to MW-12 by the existing CAP
system, as indicated on page six of the variance request, then
the appropriate action would have to be taken. If on the other
hand it is determined that the bis2 is from an ·offsite source,
then the variance could be approved based upon the contamination
that Unocal was responsible for.
If you should have any questions, I can be reached at (704)
663-1699 ext. 236.
Attachments
ajs
November 8 1 1996
Mr. Allen Schiff
North Carolina Department of
Environment, Health and Natural Resources
919 N. Main Street
Mooresville 1 NC 28115
RE: Method 625 Analyses for MW-12 Groundwater on 10/28/96
NCDEHNR Incident #3751, Priority Ranking 90/8
Unocal Corporation, Former Station #9342-811
2932 Gibbon Road, Derita, NC
S&ME Project No. 1354-92-667
Dear Mr. Schiff:
\.0 .
O"' .
:z
0 <
uJ
-0
~
~
0 -
0 n,
-,. -~:::, :;orr. on
c:~ ::;::<. cm _,..c --::;-►,;t1 --,=i::
C!:;;r: _,;,J-:;a
en
rt"i n
S&ME, Inc., on behalf of Unocal Corporation 1 sampled groundwater from deep (Type Ill)
bedrock monitor well MW-12 on October 28, 1996 after 8-hours of vacuum truck work on
October 18, 1996. Approximately 300 gallons were removed from MW-12 and properly
disposed by Enviroct:iem of Apex, NC. The Flowers Chemical Laboratory (Certification
#296) revealed no Method 625 compounds above the North Carolina Practical
Quantitative Limit of 3 ug/L in groundwater sampled from MW-12. Therefore 1 please
proceed with review of the June 13, 1996 Variance Request, per your October 23, 1996
letter.
Additionally, all Regenesis TM magnesium peroxide socks have been removed from all five
monitor wells on-site, per your request. If you have any questions or need additional
information! please call. ·
Sincerely,
S&ME, Inc.
~
Stewart M. Hines, L.G.
Senior Hydrogeologist
cc: Wayne Holt -Unocal Corporation
David Hance-NCDEHNR, Raleigh Central Office
K:\. .. \HINES\1996\SCHIFF96.N08
S&ME, Inc. 9751 Southern Pine 13oulevord, Charlotte, Norrh Carolina 2827.3, (704) 52.'.3-4726, Fox (704) 525-395.'.3
Moiling address: P.O.13ox 7668, Charlotte. North Carolina 28241-7668
The Unocal Corporation has submitted information to the Mooresville Regional
Office indicating that the presence of this substance may be due to the unintentional
release of fluids from vacuum pumping equipment used to implement the corrective
action plan for this site. Between November 3, 1994 and August 18, 1995 the
Unocal Corporation terminated the contract of a firm that was responsible for
maintaining the condition of vacuum pumps and other remediation system
components due to poor performance. Part of the reason for the termination was
that the subcontractor was not performing any maintenance on coalescing filters
used in air sparging equipment. A fluid used in these vacuum pumps is bis(2-
ethylhexyl)phthalate. As of March 20, 1996 all soil cleanup activities ceased at
this site. On July 29, 1996 the concentration of bis(2-ethylhexyl)phthalate in the
bedrock monitoring well was reported to have been reduced to 742 ppb (0.742
milligrams per liter). It must be noted that information submitted by Unocal
Corporation shows that there are a number of properties near 2932 Gibbon Road
that use groundwater as a source of drinking _water.
Based on the persistence of bis(2-ethylhexyl)phthalate at a concentration
above the level protective of human health, the possible release of this substance
into groundwater from cleanup equipment used by the company, and the continued
use of groundwater as drinking water supply, the Groundwater Section cannot
determine that the variance is complete for review by the Director in accordance
with 15A NCAC 2L .0113(d) and it cannot proceed to public notice, public
hearing, and final review by the Environmental Management Commission pursuant
to 15A NCAC 2L .0113.
In order to pursue a variance for Groundwater Incident Number 3751, the
Unocal Corporation must provide either of the following information in a variance
request:
a)
b)_
A demonstration to the Groundwater Section that the concentration
of bis(2-ethylhexyl)phthalate at this site has been reduced, by the
implementation of the cleanup technology presently at the site or an
approved corrective action plan, such that it is below 60 ppb (0.060
milligrams per liter); or 1
It is established, to the satisfaction of the Groundwater Section,
that the presence of bis(2-ethylhexyl)phthalate at this site is due to
another source of cootamination that is located offsite from the
property at 2932 Gibbon Road in Derita, North Carolina.
The additional information in items# l(a) and/or# l(b) must be provided so that the
Groundwater Section can properly evaluate the variance request and verify to the Director
that it meets the requirements of 15A NCAC 2L .0113 (c). Once the Groundwater Section
2
deems a variance request has met these requirements, it can proceed to the Director for
,-"1 review in accordance with 15A NCAC 2L .0113 (d). For this reason the request is being
returned to you. If you wish to continue pursuing a variance to the Subchapter 2L rules you will
need to submit information that addresses items #l(a) and/or #l(b). On August 12, 1996 the
Division of Epidemiology completed it's review of the risk assessment methodology and health
impacts of residual concentrations for this variance request. Based on information in the June 13,
1996 variance request, the Division of Epidemiology reported that the remaining concentrations
of all substances, except for bis(2-ethylhexyl)phthalate, were sufficiently low such that they should
not pose any future health risks to residents living adjacent to this site that continue to use
groundwater as a drinking water source. If you have any questions concerning this letter, please
contact Mr.-Allen Schiff, Mooresville Regional Office, Groundwater Section, at [phone].
Sincerely,
~7-3/'-?
Arthur Mouberry, P.E.,
Chief, Groundwater Section
APH/AM/dah
cc: Arthur Mouberry
Carl Bailey
Burtie Boshoff
Mooresville Regional Groundwater Supervisor
David Hance
A. Wayne Holt (Unocal Corporation)
3
'v_J
DIVISION OF WATER QUALITY
GROUNDWATER SECTION
August 19, 1996
MEMORANDUM:
TO: Barbara Christian, Regional Groundwater Hydrogeological Supervisor,
Mooresville Regional Office
FROM: . Arthur Mouberry, P.E., £jJ
Chief, Groundwater Sectfn"
SUBJECT: Review of Comments from the Division of Epidemiology on the Request for
Variance from 15A NCAC 2L .0106 Corrective Action Plans and 15A NCAC
2L .0202 Groundwater Quality Standards by the Unocal Corporation for a Site
at 2930 Gibbon Road in Derita, North Carolina {DWQ Groundwater Incident
Number 3751 }.
I
You will recall that on July 9, 1996, the Mooresville Regional Office was requested
to review a variance for the Unocal Corporation site in Derita, North Carolina (DWQ
Groundwater Incident _Number 3751 ). In the July 9, 1996 letter it was requested that this
variance be reviewed in light of the requirements contained in 1 SA NCAC 2L .0106 (k), (I)
and/or (m) and 15A NCAC 2L .0113(c)(1-9) and (d). In addition, we informed you that a
copy of this request was sent to Dr. Ken Rudo at the Division of Epidemiology for review
of the risk assessment methodology used by the company.
On August 12, 1996 Dr. Rudo informed that Groundwater Section that the Division
of Epidemiology cannot support a variance for this site at this time. Attached is a letter from
the 'Division of Epidemiology stating that the concentration of bis(2-ethylhexyl)phthatlate
found during routine monitoring on December 1, 1995 in monitoring well # 12 is not
protective of public health. It is Dr. Rudo's view that remediation at this site should continue
until levels have decreased below 60 micrograms per liter or 0.060 milligrams per liter.
I have been informed that due to the necessity for Mooresville Regional Office staff
to attend court on enforcement matters, the review of this variance request should be
delayed.· Please included in your recommendations on this variance a discussion of this
comment from Dr. Rudo. If it is necessary to meet and discuss this issue with Dr. Rudo,
please feel free to contact me at (919) 715-61 70. If possible, please return your
recommendation on this variance and your response to the August 12, 1996 memorandum
from Dr. Rudo to me by Tuesday September 23 , 1996.
ATTACHMENT:
cc: Carl Bailey
Burrie Boshoff
David Hance
Allen Schiff
Upon receiving your recommendation, the Section will forward a recommendation
to the Director of the Division of Environmental Management.
If you need additional assistance or information please call me at 733-3221.
cc: Carl Bailey
Dr. Burrie Boshoff
David Hance
Mooresville Regional Office Groundwater Supervisor
2
C. Since bis2 is not related to petroleum contamination, it
may have been introduced to MW-12 through the remediation
system. This statement can be supported by the following:
1. The remediation system utilized vacuum pumps and bis2
is a liquid used in vacuum pumps(see attached).
2. In the 11/3/94 sampling of MW-12, bis2 was found at
only Sppb but jumped to 2700ppb during an August 18,
1995 sampling. During this time period Unocal
utilized a separate consulting firm than S&ME to
perform O&M on the CAP system components. This
consulting firm was terminated by Unocal for
poor contract performance in part due to no maintenance
on the coaliscing filters for the sparging unit.
The MRO has requested additional information from
Unocal about the circumstances leading to the dismissal
of the consultant. The current level of bis2 was 742ppb
as of the July 29, 1996 sampling.
In light of Dr. Rudo's comments, the level of bis2 in
bedrock monitor well MW-12 and active water supply wells in the
area, the MRO finds that, at this time, a CAP in accordance with
15A NCAC 2L .0106(k), (1) and/or (m) does not appear to be 'an
option at the Unocal site. If the source of the bis2 could 'be
confirmed to have been introduced to MW-12 by the existing CAP
system, as indicated on page six of the variance request, then
the appropriate action would have to be taken. If on the other
hand it is determined that the bis2 is from an-offsite source,
then the variance could be approved based upon the contamination
that Unocal was responsible for.
If you should have any questions, I can be reached at (704)
663-1699 ext. 236.
J:>_ttachments
ajs
DIVISION OF WATER QUALITY
GROUNDWATER SECTION
July 9, 1996
MEMORANDUM:
TO:
FROM:
SUBJECT:
Barbara Christian, Regional Groundwater Hydrogeological Supervisor,
Mooresville Regional Office
Arthur Mou berry, P .E., £
Chief, G[oundwater SectiW
Review of Request for Variance from 1 SA NCAC 2L .0106 Corrective Action
Plans and 15A NCAC 2L .0202 Groundwater Quality Standards by the Unocal
Corporation for a Site at 2930 Gibbon Road in Derita, North Carolina {DEM
Groundwater Incident Number 3751 }.
Please review the attached request for a variance from the Corrective Action Plan
(CAP) rules and the Groundwater Quality Standards. Review the request in terms of the
requirements of 15A NCAC 2L .0106 Corrective Action to determine if a no corrective
action would be as effective as continuing an active CAP to remediate groundwaters at this
site. If a determination is made that a CAP involving active groundwater remediation is not
necessary, please examine the information submitted to evaluate if a corrective action under
15A NCAC 2L .0106(k)(I). and/or (m) is more appropriate. If the site is better suited for an
alternate corrective action, then send a letter to the Unocal Corporation stating your opi•nion.
Please inform the company that if they wish to continue pursuing a variance for this site, a
justification from the responsible party's environmental consultant must be sent to the
Regional Groundwater Supervisor in the Mooresville Regional Office. This justification must
outline the reasons why a variance should be granted.
If the Regional Office cannot determine that a site is any better suited for a variance
in lieu of alternate corrective action in 15A NCAC 2L .0106(k),(I) and/or (m), the consultant
for the responsible party will still need to submit a justification for this site. Please be sure
that your letter to the responsible party states that a written justification must be submitted
before the variance can proceed to public hearing.
Please note that in Appendix VI of the variance request a letter from Mr. A. Wayne
Holt of the Unocal Corporation was included in this document. This letter requested
"regulatory closure" of the site but did not specify that the responsible party is requesting
a variance under 15A NCAC 2L .0113. In your letter to the Unocal Corporation please ask
them provide clarification of whether or not they intend to continue pursuing a variance at
this site. This may be attached to the justification addressed to Mooresville Regional Office
Groundwater Supervisor.
If the responsible party expresses the desire to continue pursuing a variance at this
site and a determination is made that a CAP involving active groundwater remediation is not
necessary, please review the request for a variance in terms of the requirements itemized
in 1 SA NCAC 2L .0113, (c) (1-9), and (d). Verify technical data provided in support of the
request.
Please prepare a letter for the Director's signature providing your conclusions
regarding the request for relief from corrective action plans under 1 SA NCAC 2L .0106, the
variance request, and any additional requirements that are deemed appropriate.
A copy of this request has been sent to Dr. Ken Rudo, Division of Epidemiology, for
review of the risk asse·ssment methodology.
If possible please return your recommendation to me by Tuesday August 6, 1996.
ATTACHMENT:
cc: Carl Bailey
Burrie Boshoff
David Hance
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
A. Preston Howard, Jr., P.E., Director
,NA
DEHNR
July 9, 1996
MEMORANDUM:
TO:
FROM:
Dr. Ken Rudo, Ph .D, Toxicologist,
Environmental Epidemiology Section
Arthur Mouberry, P. E., Chief ,Jjr /
Groundwater Section G./"
SUBJECT: The Unocal Corporation Request for Variance from
15A NCAC 2L .0202 Groundwater Quality Standards
for Property at 2930 Gibbon Road in Derita, North
Carolina (DEM Groundwater Incident Number 3751}.
Attached is a variance request on behalf of the Unocal Corporation from SM&E
Incorporated. The request is for a variance to groundwater standards for Benzene,
Ethylbenzene, Toluene, Xylene (-o,-m, and -p), Methyl Tert-Butyl Ether, lsopropyl Ether,
Ethylene Dibromide, 1,2-Dichloroethane, bis(2-ethylhexyl)phthalate, Naphthalene,
1-Methylnaphthalene, 2-Methylnaphthalene, Tetrachloroethylene, Chloroform, Methylene
Chloride, and Phenol.
The request is for a site contaminated by a release of gasoline from an underground
storage tank. The area requested for variance is all the property at 2930 Gibbon Road
formerly own.ed by the Unocal Corporation. This property is presently owned by Frank
Dwyer of 2930 Gibbon Road, Derita, North Carolina. Since Unocal sold the property in
1987 this site has been used for an auto repair shop. According to information submitted
by the company, this facility is within the Town of Derita in an area of mixed residential
and commercial development. Monitoring well data indicates contamination in excess of
groundwater standards as described by 1 SA NCAC 2L .0202.
Extensive efforts have been made by the company, over the last few years, to remove
and recover free product, remediate soil, prevent the contamination of groundwater, and
cleanup groundwater. The Unocal Corporation does not believe that any public benefit can
be gained through continued groundwater remediation efforts.
Please review the attached report and provide the Groundwater Section with a
recommendation regarding this request. If possible, the Section would like to receive your
recommended response by August 6, 1996.
Groundwater Section, -a: ~ N 'k.C P.O . Box 29578 , Raleigh, North Carolina 27626-0578 W~
2728 Capital Blvd., Raleigh , North Carolina 27604 Re,:luce ~ ~le
Voice 919-733-3221 FAX [phone]
An Equal Opportunity/ Affirmative Action Employer
50"/a recycled/10% post-consumer paper
g __ ,.J V , a --.S£L,--0mr;a: I J .. .14 2.&Z&?!~·
Upon receiving your recommendation, the Section will forward a recommendation
to the Director of the Division of Environmental Management.
If you need additional assistance or information please call me at 733-3221.
cc: Carl Bailey
Dr. Burrie Boshoff
David Hance
Mooresville Regional Office Groundwater Supervisor
2
DIVISION OF WATER QUALITY
GROUNDWATER SECTION
August 19, 1996
MEMORANDUM:
TO:
FROM:
SUBJECT:
Barbara Christian, Regional Groundwater Hydrogeological Supervisor,
Mooresville Regional Office
Arthur Mouberry, P.E., V
Chief, Groundwater Sec{ffr;
Review of Comments from the Division of Epidemiology on the Request for
Variance from 15A NCAC 2L .0106 Corrective Action Plans and 15A NCAC
2L .0202 Groundwater Quality Standards by the Unocal Corporation for a Site
at 2930 Gibbon Road in Derita, North Carolina {DWQ Groundwater Incident
Number 3751 }.
You will recall that on July 9, 1996, the Mooresville Regional Office was requested
to review a variance for the Unocal Corporation site in Derita, North Carolina (DWQ
Groundwater Incident Number 3751 ). In the July 9, 1996 letter it was requested that this
variance be reviewed in light of the requirements contained in 15A NCAC 2L .0106 (k), (I)
and/or (m) and 15A NCAC 2L .0113(c)(1-9) and (d). In addition, we informed you that a
copy of this request was sent to Dr. Ken Rudo at the Division of Epidemiology for review
of the risk assessment methodology used by the company.
On August 12, 1996 Dr. Rudo informed that Groundwater Section that the Division
of Epidemiology cannot support a variance for this site at this time . Attached is a letter from
the Division of Epidemiology stating that the concentration of bis(2-ethylhexyl)phthatlate
found during routine monitoring on December 1, 1995 in monitoring well # 12 is not
protective of public health. It is Dr. Rudo 's view that remediation at this site should continue
until levels have decreased below 60 micrograms per liter or 0.060 milligrams per liter.
I have been informed that due to the necessity for Mooresvi lie Regional Office staff
to attend court on enforcement matters , the review of this variance request should be
delayed . Please included in your recommendations on this variance a discussion of this
comment from Dr. Rudo. If it is necessary to meet and discuss this issue with Dr. Rudo,
please feel free to contact me at [phone]. If possible, please return your
recommendation on this variance and your response to the August 12, 1996 memorandum
from Dr. Rudo to me by Tuesday September 23 , 1996.
ATTACHMENT:
cc: Carl Bailey
Burrie Boshoff
David Hance
Allen Schiff
November 8, 1996
Mr. Allen Schiff
North Carolina Department of
Environment, Health and Natural Resources
919 N. Main Street
Mooresville, NC 28115
RE: Method 625 Analyses for MW-12 Groundwater on 10/28/96
NCDEHNR Incident #3751, Priority Ranking 90/8
Unocal Corporation, Former Station #9342-811
2932 Gibbon Road, Derita, NC
S&ME Project No. 1354-92-667
Dear Mr. Schiff:
\.0 c,"\ .
%
0 -c:: -r...:>
~
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~
0 -
0 rn ..,,, -• :::t'
Clrr• ?3n Or,-: c:-::=<
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fT1
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S&ME, Inc., on behalf of Unocal Corporation, sampled groundwater from deep (fype 111)
bedrock monitor well MW-12 on October 28, 1996 after 8-hours of vacuum truck work on
October 18, 1996. Approximately 300 gallons were removed from MW-12 and properly
disposed by Envirochem of Apex, NC. The Flowers Chemical Laboratory (Certification
#296) revealed no Method 625 compounds above the North Carolina Practical
Quantitative Limit of 3 ug/L in groundwater sampled from MW-12. Therefore, please
proceed with review of the June 13, 1996 Variance Request, per your October 23, 1996
letter.
Additionally, all Regenesis TM magnesium peroxide socks have been removed from all five
monitor wells on-site, per your request. If you have any questions or need additional
information, please call. ·
Sincerely,
S&ME, Inc.
~
Stewart M. Hines, LG.
Senior Hydrogeologist
cc: Wayne Holt -Unocal Corporation
David Hance-NCDEHNR, Raleigh Central Office
K:\. .. \HINES\1996\SCHIFF96.N08
S&ME, Inc. 9751 Southern Pine 13oulevard, Charlotte, North Carolina 28273, (704) 52.3-4726, Fax [phone]
Mailing address: P.0.13ox 7668, Charlotte, North Carolina 28241-7668
. .
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
A Preston Howard, Jr., P.E., Director
CERTIFIED MAIL P 281 578 544
RETURN RECEIPI REQUESTED
Mr. Stewart M. Hines
S&ME Incorporated
9751 Southern Pines Blvd.,
Charlotte, NC 28273
October 23. 1996
A.VA
DEHNR
I
Subject: Request for Variance Under 15A NCAC 2L .0113 for the Unocal
Corporation at 2932 Gibbon Road in Derita, North Carolina
(Groundwater Incident# 3751)
Dear Mr. Hines:
The Division of Water Quality has reviewed the information submitted in the variance
request received on June 13, 1996 . The information contained in your request does not meet the
requirements for a variance application filed under 15A NCAC 2L .0113 for the following
reasons:
1) The supporting information to establish that the variance "will not endanger
the public health and safety, ...... " was incomplete. The request needs to
demonstrate that concentrations of substances have been sufficiently reduced or
removed from the site such that groundwater can be used in accordance with it's
best use. The classifications in 15A NCAC 2L .0201 establish by rule that the best
use of groundwater in this area is as a source of drinking water. A groundwater
sample from the bedrock monitoring well taken on August 18, 1995 revealed bis(2-
ethylhexyl)phthalate at a concentration of 2,700 ppb (2.7 milligrams per liter).
Groundwater Section,
1
Voice 919-733-3221 FAX [phone]
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
NCiC
tfffl(tiif'W
An Equal Opportunity/ Affirmative Action Employer
50% recycles/lO"k post-consumer paper
The Unocal Corporation has submitted information to the Mooresville Regional
Office indicating that the presence of this substance may be due to the unintentional
release of fluids from vacuum pumping equipment used to implement the corrective
action plan for this site. Between November 3, 1994 and August 18, 1995 the
Unocal Corporation terminated the contract of a firm that was responsible for
maintaining the condition of vacuum pumps and other remediation system
components due to poor performance. Part of the reason for the termination was
that the subcontractor was not performing any maintenance on coalescing filters
used in air sparging equipment. A fluid used in these vacuum pumps is bis(2-
ethylhexy l)phthalate. As of March 20, 1996 all soil cleanup activities ceased at
this site. On July 29, 1996 the concentration of bis(2-ethylhexyl)phthalate in the
bedrock monitoring well was reported to have been reduced to 742 ppb (0. 742
milligrams per liter). It must be noted that information submitted by Unocal
Corporation shows that there are a number of properties near 2932 Gibbon Road
that use groundwater as a source of drinking water.
Based on the persistence of bis(2-ethylhexyl)phthalate at a concentration
above the level protective of human health, the possible release of this substance
into groundwater from cleanup equipment used by the company, and the continued
use of groundwater as drinking water supply, the Groundwater Section cannot
determine that the variance is complete for review by the Director in accordance
with 15A NCAC 2L .0113(d) and it cannot proceed to public notice, public
hearing, and final review by the Environmental Management Commission pursuant
to 15A NCAC 2L .0113.
In order to pursue a variance for Groundwater Incident Number 3751, the
Unocal Corporation must provide either of the following information in a variance
request:
a)
b)_
A demonstration to the Groundwater Section that the concentration
of bis(2-ethylhexyl)phthalate at this site has been reduced, by the
implementation of the cleanup technology presently at the site or an
approved corrective action plan, such that it is below 60 ppb (0.060
milligrams per liter); or
It is established, to the satisfaction of the Groundwater Section,
that the presence of bis(2-ethylhexyl)phthalate at this site is due to
another source of contamination that is located offsite from the
property at 2932 Gibbon Road in Derita, North Carolina.
The additional information in items # l(a) and/or # l(b) must be provided so that the
Groundwater Section can properly evaluate the variance request and verify to the Director
that it meets the requirements of 15A NCAC 2L .0113 (c). Once the Groundwater Section
2
deems a variance request has met these requirements, it can proceed to the Director for
review in accordance with 15A NCAC 2L .0113 (d). For this reason the request is being
returned to you. If you wish to continue pursuing a variance to the Subchapter 2L rules you will
need to submit information that addresses items #l(a) and/or #l(b). On August 12, 1996 the
Division of Epidemiology completed it's review of the risk assessment methodology and health
impacts of residual concentrations for this variance request. Based on information in the June 13,
1996 variance request, the Division of Epidemiology reported that the remaining concentrations
of all substances, except for bis(2-ethylhexyl)phthalate, were sufficiently low such that they should
not pose any future health risks to residents living adjacent to this site that continue to use
groundwater as a drinking water source. If you have any questions concerning this letter, please
contact Mr. Allen Schiff, Mooresville Regional Office, Groundwater Section, at [phone].
APH/AM/dah
cc: Arthur Mouberry
Carl Bailey
Burrie Boshoff
Sincerely,
~~~?
Arthur Mouberry, P.E.,
Chief, Groundwater Section
Mooresville Regional Groundwater Supervisor
David Hance
A. Wayne Holt (Unocal Corporation)
3
MEMORANDUM TO: Arthur Mouberry
FROM: Allen Schiff all
THROUGH: Barbara Christian.lJc.-
DIVISION OF WATER QUALITY
September 23, 1996
' }
SUBJECT: Review of Variance Request for
Former Unocal Facility No. 9342-811
2932 Gibbon Road
~ .. :;.~ ;·~. ~
Priority Rank 90/B
Mecklenburg County, N.C.
Groundwater Incident No. 3751
Upon review of the June 1996 variance request, the
Groundwater Incident file for the subject site and Dr. Ken Rudo's
comments, the MRO offers the following:
1. The petroleum contaminant plume appears to be almost
completely remediated except for Benzene(3.34ppb) and 1,2-
dichloroethane(24.8ppb) found in deep(bedrock) monitor well
MW-12 per the most recent sampling conducted July 29, 1996.
Additionally, bis(2-ethylhexyl)phthalate(hereinafter bis2) was
found in MW-12 at a concentration of 742ppb.
2. Air sparging and SVE were utilized at the site to remediate
the petroleum plume that contained BTEX as high as 31,l00ppb
(MW-14), prior to CAP implementation, to BDL in the same well as
of the July 1996 sampling event.
3. Dr. Rudo indicates in his August 12, 1996, memo that he
cannot support the variance request due to the high level of bis2
found in MW-12. His recommendation is further remediation of the
bis2 constituent. I offer the following items for consideration
with respect to Dr. Rudo's comments and Unocals options:
A. The existing air sparging/SVE system could not be utilized
to remediate the bis2 in MW-12 because it is a bedrock
well where uncontrolled sparging is not advisable. This
would require Unocal to implement a separate CAP system to
remediate the bis2.
B. Unocal has expended in excess of $751,863 at the site
that has previously been determined to not be reimbursable
from the STF. In addition, O&M costs for the existing
CAP system would total approximately $20,000 annually when
the system was in operation.
C. Since bis2 is not related to petroleum contamination, it
may have been introduced to MW-12 through the remediation
system. This statement can be supported by the following:
1. The remediation system utilized vacuum pumps and bis2
is a liquid used in vacuum pumps(see attached).
2. In the 11/3/94 sampling of MW-12, bis2 was found at
only Sppb but jumped to 2700ppb during an August 18,
1995 sampling. During this time period Unocal
utilized a separate consulting firm than S&ME to
perform O&M on the CAP system components. This
consulting firm was terminated by Unocal for
poor contract performance in part due to no maintenance
on the coaliscing filters for the sparging unit.
The MRO has requested additional information from
Unocal about the circumstances leading to the dismissal
of the consultant. The current level of bis2 was 742ppb
as of the July 29, 1996 sampling.
In light of Dr. Rudo's comments, the level of bis2 in
bedrock monitor well MW-12 and active water supply wells in the
area, the MRO finds that, at this time, a CAP in accordance with
15A NCAC 2L .0106(k), (1) and/or (m) does not appear to be an
option at the Unocal site. If the source of the bis2 could be
confirmed to have been introduced to MW-12 by the existing CAP
system, as indicated on page six of the variance request, then
the appropriate action would have to be taken. If on the other
hand it is determined that the bis2 is from an offsite source,
then the variance could be approved based upon the contamination
that Unocal was responsible for.
If you should have any questions, I can be reached at (704)
663-1699 ext. 236.
Attachments
ajs
DIVISION OF WATER QUALITY
September 23, 1996
MEMORANDUM TO: Arthur Mouberry
FROM: Allen Schiff aJ
THROUGH:
SUBJECT:
Barbara Christian .UC--
Review of Variance Request for
Former Unocal Facility No. 9342-811
2932 Gibbon Road
\C, v·l
U')
rrl
7)
!'.) -
-i:,
)
-
Priority Rank 90/B , I
Mecklenburg County, N.C.
Groundwater Incident No. 3751
Upon review of the June 1996 variance request, the
Groundwater Incident file for the subject site and Dr. Ken Rudo's
comments, the MRO offers the following:
1. The petroleum contaminant plume appears to be almost
completely remediated except for Benzene(3.34ppb) and 1,2-
dichloroethane(24.8ppb) found in deep(bedrock) monitor well
MW-12 per the most recent sampling conducted July 29, 1996.
Additionally, bis(2-ethylhexyl)phthalate(hereinafter bis2) was
found in MW-12 at a concentration of 742ppb.
2. Air sparging and SVE were utilized at the site to remediate
the petroleum plume that contained BTEX as high as 31,l00ppb
(MW-14), prior to CAP implementation, to BDL in the same well as
of the July 1996 sampling event.
3. Dr. Rudo indicates in his August 12, 1996, memo that he
cannot support the variance request due to the high level of bis2
found in MW-12. His recommendation is further remediation of the
bis2 constituent. I offer the following items for consideration
with respect to Dr. Rudo's comments and Unocals options:
A. The existing air sparging/SVE system could not be utilized
to remediate the bis2 in MW-12 because it is a bedrock
well where uncontrolled sparging is not advisable. This
would require Unocal to implement a separate CAP system to
remediate the bis2.
B. Unocal has expended in excess of $751,863 at the site
that has previously been determined to not be reimbursable
from the STF. In addition, O&M costs for the existing
CAP system would total approximately $20,000 annually when
the system was in operation.
C. Since bis2 is not related to petroleum contamination, it
may have been introduced to MW-12 through the remediation
system. This statement can be supported by the following:
1. The remediation system utilized vacuum pumps and bis2
is a liquid used in vacuum pumps(see attached).
2. In the 11/3/94 sampling of MW-12, bis2 was found at
only Sppb but jumped to 2700ppb during an August 18,
1995 sampling. During this time period Unocal
utilized a separate consulting firm than S&ME to
perform O&M on the CAP system components. This
consulting firm was terminated by Unocal for
poor contract performance in part due to no maintenance
on the coaliscing filters for the sparging unit.
The MRO has requested additional information from
Unocal about the circumstances leading to the dismissal
of the consultant. The current level of bis2 was 742ppb
as of the July 29, 1996 sampling.
In light of Dr. Rudo's comments, the level of bis2 in
bedrock monitor well MW-12 and active water supply wells in the
area, the MRO finds that, at this time, a CAP in accordance with
lSA NCAC 2L .0106(k), (1) and/or (m) does not appear to be an
option at the Unocal site. If the source of the bis2 could be
confirmed to have been introduced to MW-12 by the existing CAP
system, as indicated on page six of the variance request, then
the appropriate action would have to be taken. If on the other
hand it is determined that the bis2 is from an offsite source,
then the variance could be approved based upon the contamination
that Unocal was responsible for.
If you should have any questions, I can be reached at (704)
663-1699 ext. 236.
Attachments
ajs
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
A. Preston Howard, Jr., P.E., Director
AVA
D EH NR
July 9, 1996
MEMORANDUM;
TO: Dr. Ken Rudo, Ph.D, Toxicologist,
Environmental Epidemiology Section
FROM: Arthur Mouberry, P.E., Chief
Groundwater Section
SUBJECT: The Unocal Corporation Request for Variance from
15A NCAC 2L .0202 Groundwater Quality Standards
for Property at 2930 Gibbon Road in Derita, North
Carolina (DEM Groundwater Incident Number 3751}.
Attached is a variance request on behalf of the Unocal Corporation from SM&E
Incorporated. The request is for a variance to groundwater standards for Benzene,
Ethylbenzene, Toluene, Xylene (-o,-m, and -p), Methyl Tert-Butyl Ether, lsopropyl Ether,
Ethylene Dibromide, 1,2-Dichloroethane, bis(2-ethylhexyl)phthalate, Naphthalene,
1-Methylnaphthalene, 2-Methylnaphthalene, Tetrachl.oroethylene, Chloroform, Methylene
Chloride, and Phenol.
The request is for a site contaminated by a release of gasoline from an underground
storage tank. The area requested for variance is all the property at 2930 Gibbon Road formerly
owned by the Unocal Corporation. This property is presently owned by Frank Dwyer of 2930
Gibbon Road, Derita, North Carolina. Since Unocal sold the property in 1987 this site has
been used for an auto repair shop. According to information submitted by the company, this
facility is within the Town of Derita in an area of mixed residential and commercial
development. Monitoring well data indicates contamination in excess of groundwater
standards as described by 1 SA NCAC 2L .0202.
Extensive efforts have been made by the company, over the last few years, to remove
and recover free product, remediate soil, prevent the contamination of groundwater, and
cleanup groundwater. The Unocal Corporation does not believe that any public benefit can
be gained through continued groundwater remediation efforts.
Please review the attached report and provide the Groundwater Section with a
recommendation regarding this request. If possible, the Section would like to receive your
recommended response by August 6, 1996.
Groundwater Section,
P.O. Box 29578, Raleigh, North Carolina 27626-0578
2728 Capital Blvd., Raleigh, North Carolina 27604
N!)C
ffffirti'fMeP
Voice 919-733-3221 FAX [phone]._88
An Equal Opportunity/ Affirmative Action Employer
50% recycles/10% post-consumer paper
Upon receiving your recommendation, the Section will forward a recommendation to
the Director of the Division of Environmental Management.
If you need additional assistance or information please call me at 733-3221.
cc: Carl Bailey
Dr. Burrie Boshoff
David Hance
Mooresville Regional Office Groundwater Supervisor
2
DIVISION OF WATER QUALITY
GROUNDWATER SECTION
July 9, 1996
MEMORANDUM:
TO:
FROM:
SUBJECT:
Barbara Christian, Regional Groundwater Hydrogeological Supervisor,
Mooresville Regional Office
Arthur Mouberry, P.E.,
Chief, Groundwater Section
Review of Request for Variance from 1 SA NCAC 2L .0106 Corrective Action
Plans and 1 SA NCAC 2L .0202 Groundwater Quality Standards by the Unocal
Corporation for a Site at 2930 Gibbon Road in Derita, North Carolina {DEM
Groundwater Incident Number 3751 }.
Please review the attached request for a variance from the Corrective Action Plan (CAP)
rules and the Groundwater Quality Standards. Review the request in terms of the requirements
of 1 SA NCAC 2L .0106 Corrective Action to determine if a no corrective action would be as
effective as continuing an active CAP to remediate groundwaters at this site. If a determination
is made that a CAP involving active groundwater remediation is not necessary, please examine
the information submitted to evaluate if a corrective action under 1 SA NCAC 2L .0106(k)(I)
and/or (m) is more appropriate. If the site is better suited for an alternate corrective action,
then send a letter to the Unocal Corporation stating your opinion. Please inform the company
that if they wish to continue pursuing a variance for this site, a justification from the
responsible party's environmental consultant must be sent to the Regional Groundwater
Supervisor in the Mooresville Regional Office. This justification must outline the reasons why
a variance should be granted.
If the Regional Office cannot determine that a site is any better suited for a variance
in lieu of alternate corrective action in 1 SA NCAC 2L .0106(k),(I) and/or (m), the consultant
for the responsible party will still need to submit a justification for this site. Please be sure
that your letter to the responsible party states that a written justification must be submitted
before the variance can proceed to public hearing.
Please note that in Appendix VI of the variance request a letter from Mr. A. Wayne Holt
of the Unocal Corporation was included in this document. This letter requested "regulatory
closure" of the site but did not specify that the responsible party is requesting a variance under
1 SA NCAC 2L .0113. In your letter to the Unocal Corporation please ask them provide
clarification of whether or not they intend to continue pursuing a variance at this site. This
may be attached to the justification addressed to Mooresville Regional Office Groundwater
Supervisor.
If the responsible party expresses the desire to continue pursuing a variance at this site
and a determination is made that a CAP involving active groundwater remediation is not
necessary, please review the request for a variance in terms of the requirements itemized in
1 SA NCAC 2L .0113, (c) (1-9), and (d). Verify technical data provided in support of the
request.
Please prepare a letter for the Director's signature providing your conclusions regarding
the request for relief from corrective action plans under 1 SA NCAC 2L .0106, the variance
request, and any additional requirements that are deemed appropriate.
A copy of this request has been sent to Dr. Ken Rudo, Division of Epidemiology, for
review of the risk assessment methodology.
If possible please return your recommendation to me by Tuesday August 6, 1996.
ATTACHMENT:
cc: Carl Bailey
Burrie Boshoff
David Hance