NC0004626_Permit (Issuance)_19950801

NPDES DOCUWENfT SCANNING COVER SHEET
NPDES Permit: NC0004626
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Document Type: f Permit Issuance�`N,
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Speculative Limits
Staff Report
Instream Assessment (67B)
Environmental Assessment (EA)
Permit
History
Document Date: Aupist 1, 1995
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State of North Carolina
Department of Environment, 4
Health and Natural Resources 4 • •
Division of Environmental Management
James B. Hunt,Jr., Governor
Jonathan B. Howes, Secretary p E,H N R
A. Preston Howard, Jr., P.E., Director
August 1,1995
Mr.James W.Buchanan
PPG Industries,Inc/Environmental and Chemical Technology
Post Office Box 949
473 New Jersey Church Road
Lexington,North Carolina 27293
Subject. Fu%al Resolution of NPDES Permit Adjudication
Permit No. NCOOD4626
PPG Industries,Inc(Lexington Facility)
Davidson County
Dear Mr, Buchanan
The Division is forwarding NPDES Permit No.NCD004626. This permit is issued pursuant to the
requirements of North Carolina General Statute 143-215.1 and the Memorandum of Agreement between North
Carolina and the U.S.Environmental Protection Agency dated December 6,1983.
The attached is a modified NPDES permit which represents the resolution of your petition for a
contested case. The resolution of issues can be sununarized:
• Instream sampling will be done via grab samples.
• Laboratory detection limits will be specified for nutrient samples collected as part
of the water quality sampling in the streams and lake arms. Since these data are crucial in
making future decisions about discharge location and PPG's affect on nutrient loading to the
lake,the Division finds it necessary to require analysis at the low levels specified in the
permit.
• PPG Industries,Inc.agreed to monitor for total suspended solids on a twice per month basis as
originally written in the contested NPDES permit.
• AnaIyses for fecal coliform monitoring will also remain the same as required in the
contested permit as the Division and PPG Industries,Inc.agreed.
• As requested at the June 30,1995 meeting,Total Nitrogen has been replaced on the effluent
limits pages by NO2+NO3 and TKN.
• Finally,the permit has been modified to clarify monitoring of the streams and lake
arms. As discussed between you,Mickey LeCroy(PPG Industries,Inc.),Steve Bevington
(Environmental Modeling Supervisor),and David Goodrich(NPDES Supervisor)on June 30,
1995,sampling will be performed once during the summer of 1995 and once during the summer of
1996. Sampling stations will include ten stations—five in North Potts Creek and five in
Swearing Creek The timing of the sampling will be coordinated with the Division. Details of
this effort are discussed in the attached NPDES permit under Part III,Special Condition G,
which has been revised per your July 24,1995 letter to Mr.Goodrich It is the intention of the
Division to review the data collected as part of the Yadkin River Basinwide Management Plan
which will be drafted in 1997. The Division also understands that PPG Industries,Inc.would
like the relocation of the outfall line from North Potts Creek to Swearing Creek to be considered
upon receipt of results and furtherdiscussion.
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone] FAX [phone]
An Equal Opportunity Affimative Action Emptoyer 50%recyd"1 D%post-consumer paper

Although not an issue specifically contested during this adjudication,the Division encourages PPG
Industries,Inc.to pursue reductions of total phosphorus and total nitrogen It was also recognized during
negotiations of this case that PPG Industries,Inc. may be able to use reclaimed wastewater to irrigate
the grounds of the facility. Even partial reuse of this wastewater,with an'emergency'discharge
provision in the permit,would be beneficial to the waters of High Rock Lake. Attached for your review
is a copy of the draft rules for the reuse of reclaimed wastewater. These rules were brought forward to
the Water Quality Committee of the Environmental Management Commission in July and are expected
to be sent to public hearings in the autumn of this year. As discussed in the June 30,1995 nweting,PPG
Industries,Inc.will provide the Division with an annual report on the progress made towards reduction
in nutrients discharged as well as any considerations regarding reuse of wastewater. The report can
certainly take the form of a letter,and will be due on June 30th of 1996 and 1997.
Please take notice this permit is not transferable. Part II,E.4.addresses the requirements to be
followed in case of change in ownership or control of this discharge.
This permit does not affect the legal requirements to obtain other permits which may be
required by the Division of Environmental Management or permits required by the Division of Land
Resources,Coastal Area Management Act or any other Federal or Local governmental permit that may
be required.
Attached is a petition for withdrawal of contested case. Please sign this form and send the original to
the Office of Administrative Hearings and one copy to the Attorney General's Office in care of Jill
Hickey. If you would like to speak to someone regarding the permit,please call David Goodrich of my
staff at E9191"733-5083, extension 517.
Respectfully,
original Signed Bil
C, leen H. Stil ins
A.Preston Howard,Jr.,P.E.
or- Central Files
Winston-Salem Regional Office
Mr. Roosevelt Childress,EPA
Permits&Engineering Unit
Facility Assessment Unit
Aquatic Survey and Toxicology Unit
Attorney General's Office,Jill Hickey
Instream Assessment Unit,Steve Bevington

Permit No. NCOOD4626
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT, HEALTH,.AND NATURAL RESOURCES
DIVISION OF ENVIRONMENTAL MANAGEMENT
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATIQU �jY,SJEM
In compliance with the provision of North Carolina General Statute 143-215.1,
other lawful standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, as amended,
PPG Industries, Inc.
is hereby authorized to discharge wastewater from a facility located at
PPG Industries, Inc., Lexington
New Jersey Church Road
Lexington
Davidson County
to receiving waters designated as North Potts Creek in the Yadkin-Pee Dee River Basin
in accordance with effluent limitations, monitoring requirements, and other conditions set forth in
Parts 1, II, and III hereof.
This permit shall become effective September 1, 1995
This permit and the authorization to discharge shall expire at midnight on July 31, 1998
Signed this day August 1, 1995
Orlpnal.Signed B'f
Coleen H. Sullins
A. Preston Howard, Jr., P.E., Director
Division of Environmental Management
By Authority of the Environmental Management Commission

Permit No. NC0004626 -
SUPPLEMENT TO PERMIT COVER SHEET
PPG Industries, Inc.
is hereby authorized to:
1 . Continue to operate a wastewater treatment facility consisting of a mechanical bar screen,
comminutor, equalization basin,chemical mixing tanks, primary clarifier, nutrient addition, dual
aeration basins, final clarifiers, gas chlorination,chlorine contact chamber and dual ' t"7
filters located at PPG Industries, Inc., Lexington, New Jersey Church Road, Lexington,
Davidson County (See Pant III of this Permit), and
--,•,fT-, /� // a_i�•�S.�i-.ram
2. Discharge from said treatment works at the location specified on the attached map into North
Potts Creek which is classified Class C waters in the Yadkin-Pee Dee River Basin.

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A. (1). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS SUMMER (April 1 - October 31) Permit No. NCO004626
During the period beginning on the effective date of the permit and lasting expiration, the Permittee is authorized to discharge from
outfall(s)serial number 001. Such discharges shall be limited and monitored by the permittee as specified below;
Effluent_ Characteristics Monitoring nen lu rem2nts
Lb_slday Units (SA_eglty) Measurement _Sams 'Sample
Mon---Avg. Daily MaX. Mon. ,_Ava. Dolly Max. Ereq oux Type_ Location
Flow 0.6 MGD Continuous Recording I or E
BOD, 5-Day, 20°C 157.0 314.0 Daily Composite E
Fecal Coliform 200.0 /100ml 400.0 /100ml 21month Grab E
Total Suspended Solids 105.0 168.0 2/month Composite E
cco Quarterly Composite E
NH3 as N Weekly Composite E
Oil and Grease 30.0 mg/l 60.0 mg/l 21month Grab E
Residual Chlorine Daily Grab E
Temperature Weekly Grab E
TKN Monthly Composite E
NO2+NO3 Monthly Composite E
Total Phosphorus Monthly Composite E
Chronic Toxicity" Quarterly Composite E
* Sample locations: E-Effluent, I - Influent. PLEASE NOTE: See Part III, Special Condition G for instream monitoring requirements.
** Chronic Toxicity (Ceriodaphnia)P/F @ 48.0%; February,May,August, November, see Part III, Condition E.
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units at the effluent. Effluent monitoring shall be conducted daily by
grab samples.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

A. (2).EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS WINTER (November 1 - March 31) Permit No. NC0004626
During the period beginning on the effective date of the permit and lasting expiration, the Permittee is authorized to discharge from
outfall(s) serial number 001. Such discharges shall be limited and monitored by the penxuttee as specified below:
Effluent CharprJeristic.9 UIscharge Llmltatlons Monitoting _ Requirements
1_bs/darn units (SeeeLiv) Measurement _SamnEe__ •Semple
Mon. Avg, Daily Max. Mon. Avg. Daily Max. Frequency_ Type Location
Flow 0.6 MGD Continuous Recording I or E
SOD, 5-Day, 20°C 314.0 630.0 Daily Composite E
Fecal Coliiorm 200.0 /100ml 400.0 /1.00ml 2/month Grab E
Total Suspended Solids 146.0 292.0 2/month Composite E
OCD Quarterly Composite E
NH3 as N Weekly Composite E
Oil and Grease 30.0 mg/I 60.0 mg/l 2/month Grab E
Residual Chlorine Daily Grab E
NO2+NO3 Monthly Composite E
TKN Monthly Composite E
Total Phosphorus Monthly Composite E
Chronic Toxicity" Quarterly Composite E
* Sample locations:E-Effluent,I-Influent.
** Chronic Toxicity (Ceriodaphnia) P/F @ 48.0%; February,May,August, November, see Part III, Condition E.
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units at the effluent. Effluent monitoring shall be conducted daily by
grab samples.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

Part III Permit No. NC0004626
E. CHRONIC TOXICITY PASSIFAIL PERMIT LIMIT(QRTRLY)
The effluent discharge shall at no time exhibit chronic toxicity using test procedures outlined in:
1.) The North Carolina Ceriodaphnia chronic effluent bioassay procedure (North Carolina Chronic
Bioassay Procedure - Revised *September 1989) or subsequent versions.
The effluent concentration at which there may be no observable inhibition of reproduction or
significant mortality is 48.0% (defined as treatment two in the North Carolina procedure
document). The permit holder shall perform quarterly monitoring using this procedure to establish
compliance with the permit condition. The first test will be performed after thirty days from the
effective date of this permit during the months of February, May, August, November. Effluent
sampling for this testing shall be performed at the NPDES permitted final effluent discharge below
all treatment processes.
All toxicity testing results required as part of this permit condition will be entered on the Effluent
Discharge Monitoring Form (MR-1) for the month in which it was performed, using the parameter
code TGP3B. Additionally,DEM Form AT-1 (original)is to be sent to the following address:
Attention:
Environmental Sciences Branch
North Carolina Division of
Environmental Management
4401 Reedy Creek Road
Raleigh, N.C. 27607
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual
chlorine of the effluent toxicity sample must be measured and reported if chlorine is employed for
disinfection of the waste stream.
Should any single quarterly monitoring indicate a failure to meet specified limits, then monthly
monitoring will begin immediately until such time that a single test is passed. Upon passing, this
monthly test requirement will revert to quarterly in the months specified above.
Should any test data from this monitoring requirement or tests performed by the North Carolina
Division of Environmental Management indicate potential impacts to the receiving stream, this
permit may be re-opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum
control organism survival and appropriate environmental controls, shall constitute an invalid test
and will require immediate retesting(within 30 days of initial monitoring event). Failure to submit
suitable test results will constitute noncompliance with monitoring requirements.

F. MINIMUM DETECTION LEVELS FOR NUTRIENTS(for samples collected in the stream and lake)
TP-0.01 EVA
NO2-0.01 mg/l
NO3-0.1 mg/l
NH3 as N-0.1 mg/l
TKN-0.1 mg/l
G. INSTREAMAN-LAKE MONITORING
PPG Industries,Inc. shall sample North Potts Creek and Swearing Creek once during the summer of 1995
and once during the summer of 1996 at the locations specified on the attached map. Sampling shall be
coordinated with Mr.Jim Blose of the Instream Assessment Unit and will be undertaken after any 10-day
period between July 1 through September 1 in which there are no precipitation events in excess of 0.1
inches, If such a period does not occur in either year,the Division and the permittee.may agree on an
alternate condition,or the condition will be waived for that year. Samples will be collected as follows:
Instream Monitoring Staiions/Parameters
STATION NUMBER LOCATION SAMPLE PARAMETERS*
NP- 1 North Potts Creek DO,Temp.,Conductivity,pH,
at SR 1134 TP,NO2+ NO3, NH3. TKN
SWC-1 Swearing Creek DO,Temp.,Conductivity,pH,
near Highway 47 TP, NO2 + NO3, NH3,TKN
*All samples shall be collected at 0.1 meters beneath the surface of the water in the stream.
Lake Monitoring Stations/Parameters
,STATION NUMBER LOCATION SAMPLE PARAMETERS**
NP-2 North Potts Creek DO,Temperature,Conductivity,pH,
near Railroad Tracks TP,NO2 + NO3,NH3,TKN,Chlorophyll-a
NP-3 North Potts Creek DO,Temperature,Conductivity,pH,
near PPG outfall TP,NO2 + NO3,NH3,TKN,Chlorophyll-a
NP-4 North Potts Creek DO,Temperature,Conductivity,pH,
between NP-3 and NP-5 TP.NO2 + NO3,NH3,TKN,Chlorophyll-a
NP-5 North Potts Creek DO,Temperature,Conductivity,pH,
near mouth TP,NO2 +NO3,NH3,TKN, Chlorophyll-a
SWC-2 Swearing Creek lake arm DO,Temperature,Conductivity,pH,
(see map) TP,NO2 + NO3,NH3,TKN,Chlorophyll-a
SWC-3 Swearing Creek lake arm DO,Temperature,Conductivity,pH,
(see map) TP, NO2 + NO3,NH3,TKN,Chlorophyll-a
SWC-4 Swearing Creek lake arm DO,Temperature,Conductivity,pH,
near Linwood Southmont Rd. TP,NO2 + NO3,NH3,TKN, Chlorophyll-a
SWC-5 Swearing Creek lake arm DO,Temperature,Conductivity,pH,
near mouth TP, NO2 + NO3, NH3, TKN, Chlorophyll-a
**Nutrient,pH,and Chlorophyll-a samples will only be collected at 0.1 meters beneath the surface of the
water in the lake. However,DO,Temperature,and Conductivity measurements shall be made at the
surface of the water column as well as the middle of the water column and the bottom of the water column.

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PPG INDUSTRIES, INC./P.O. BOX 9491LEXINGTON, NORTH CAROLINA 272931AREA 704/249-8151
Works No, 53
Fiber Glass Products
A.Preston Howard,Jr. April 21,1995
Director,Division of Environmental Management.
Department of Environment,Health and Natural Resources
P.4.Box 29535
Ralei gh,N.C. 27626-0535
Dear Mr.Howard:
I am writing in response to your letter of March 22,1995 ,transmitting NPDES
Permit No. NC0004626.I am particularly responding to the comments on the issues
raised by PPG Industries,Inc. ("PPG") regarding a number of monitoring and
reporting conditions included in the proposed permit,and proposing a different
approach to resolution of the issues.
The rationale stated for many of the monitoring requirements seems to be tied
to conditions in High Rock Lake and to the development of a water quality
management plan for High Rock Lake.PPG recognizes the fact that water quality in
High Rock Lake needs to be protected,and the development of a management plan for
the lake may be a cost-effective and rational means for assuring this
protection.However,we do not believe that effluent from PPG significantly contributes
to the problems experienced in High Rock Lake.
Nevertheless,PPG is willing to work cooperatively with the Division of
Environmental Management ("DEM") in connection with the development of the water
quality management plan.PPG is willing to explore with DEM a role by which PPG
undertakes additional monitoring for nutrients in North Potts Creek,but would prefer
that the monitoring be conducted pursuant to an agreement between DEM and
PPG,and not as terms and conditions in NPDES Permit No.NC0004626,which we
believe to be inappropriate to the nature of PPG's effluent.
To provide some background to PPG's position,I have provided some brief
comments to the staff responses to PPG positions on the monitoring conditions which
were addressed in your letter:
Issue: Part 1,Section A.Sample Type and Frequency
This provision requires that instream samples of nutrients must be composites
rather than grab samples.15A NCAC 2B.0505(c)(3)(A) states that " [slamples

'N
collected in receiving waters shall be grab samples."Furthermore,the special
provisions for monitoring of total Nitrogen and total Phosphorus do not call for
composite sampling for these parameters.15A NCAC 2B.0508(d).Therefore it
appears that DEM rules do not require that instream samples be
composites.Certainly, neither the permit nor the rules require the specialized
type of composite described in the letter.
Issue: Part III,Section F.Minimum Detection Levels for NutrientsVr - DAL c,✓
b . There is no effluent limitation for either Nitrogen or Phosphorus imposed in the
/1 Permit.Thus,while the assertion that "instream nutrient concentrations should
o'" _sr be significantly lower that effluent concentrations" may be defensible,and may
have some significance with respect to the quality of the water in High Rock
Lake,it ignores the fact that PPG's effluent is not a significant contributor of -
nutrients.PPG presently utilizes a testing protocol which satisfies the
requirements of 15A NCAC 2B_0505(e)(4).
1
Issue:Fecal Coliform,Effluent and Instxeam Monitor_ cGoopa 7 ges
While PPG's effluent may not satisfy a 331:1 dilution ratio threshold compared
to the 7Q 10 flow of North Potts Creek,the domestic component of PPG's effluent
represents less than 10% of its total effluent flow.We note that the 331:1
dilution ratio criterion is not a rule,but rather a "standard procedure:".
Presumably,that distinction means that DEM enjoys a greater degree of flexibility
in the application of the criterion,perhaps in recognition of situations comparable
to that of PPG.
.kf7a Issue: Stream Monitoring,Chlorophyll-a,TKN,NH3,NO.
n•
�.o The chlorophyll-a analytical procedure will cost over $800 for the proposed 5
Nv3 t C) month (June-October) sampling period for each year of the life of the permit.
PPG understands that standard testing protocols for chlorophyll-a tend to
overstate_ the amount of chlorophyll-a actually present in a samNle.Therefore,it
appears that the test may be of dubious value for the purpose DEM intends.I note
also that the instream samples for each of the above referenced parameters is required
by the terms of the proposed permit to be a composite.
If the purpose of the above referenced monitoring requirements is indeed to provide
data for development of a water quality management plan for High Rock Lake,PPG is
willing to cooperate in the development of the plan.In fact,PPG would propose expanding
the data collection to Swearing Creek,provided that the data
,collected in that effort could also be considered by DEM in support of a modification to
NPDES Permit No. NC0004026 to allow PPG to relocate its discharge point to Swearing
Creek,a waterbody presently traversed by the discharge pipes from the PPG plant.
1�

In the meantime,the 30-day period during which PPG has to contest conditions
imposed in NPDES Permit No. NC0004626 expires shortly.We are advised by counsel
that,in order to protect its rights,PPG must file a petition for contested case hearing on or
before Monday,April 24,1995.We understand that it is not possible for you to properly
review and act on our suggestions by that time,but we want to assure you that PPG would
prefer to creatively approach and resolve these issues in the manner described,rather than
contesting the permit.Th e petition in this matter is purely protective,filed on advice of
counsel.Our counsel does not believe that filing the petition should pose any
insurmountable problems with regard to continuation of discussions with DEM staff.I
hope that you will agree that the petition is not an impediment to this process.
I look forward to meeting with you or your staff to resolve these issues.Please feel
free W contact me at 704-352-3184 or 704-249-8151 to discuss the matter further.
Best regards,
W'.Buchanan
Senior Engineering Associate
Environmental. Affairs
cc: David Goodrich,DEM
Steve Mauney ,WSRO
C.Bromby
M.Reilly
M.LeCroy
J.Muraco
D.Segers
L.Ballard

DIVISION OF ENVIRONMENTAL MANAGEMENT
Water Quality Section/lnstream Assessment Unit
October 4, 1994
MEMORANDUM
TO: Sean Goris
FROM: 413ets-J6ti6iso
SUBJECT: PPG Industr' draft permit
NPDES No. NCO004626
Davidson County
Fecal Coliform -though the facility is only 10%domestic and there is no evidence that the
wastewater contains no fecal coliform. Whether, PPG uses chlorine for disinfection or to keep its
pipes clean, PPG's chlorine use is excessive. PPG's average daily chlorine levels of 0.4 mg/are
toxic. PPG should monitor for fecal colonies before and after chlorination and take steps to
reduce chlorine levels. Please refer to the chlorine letter which was sent to domestic facilities. In
addition, it is recommended that chlorine be sampled at the en 'ot pipe to determine if toxic
levels of chlorine remain.
Copper and Chromium - monitoring was recommended due to the poor compliance record for
toxicity; it is likely that toxicity failures are due to excessive chlorine use. Monitoring may be
dropped.
ff you have questions regarding these comments, please let me know.
cc: Winston-Salem Regional Office

DIVISION OF ENVIRONMENTAL MANAGEMENT
Water Quality Section/Instream Assessment Unit t�
September 9, 1994
MEMORANDUM �0
b
TO: Sean Gods
FROM: Betsy Johnson
THROUGH: Steve Bevingt �P
Ruth Swanek
SUBJECT: PPG Industries draft permit
NPDES No. NCO004626
Davidson County
I have reviewed the comments provided by PPG Industries regarding its draft permit for discharge to Potts Creek, a
tributary of High Rock Lake. My comments are provided below.
Instream monitoring samples for nutrients should be spatial composites within the photic zone(defined as twice the
secchi depth). The permit is correct as written.
Minimum detection levels for nutrients were provided as a strong recommendation; if higher detection levels are used,
the data may be meaningless. Instream levels of nutrients should be significantly lower than effluent levels hence
lower detection levels should be used. For example it is inappropriate to report TP as less than 1 mg/l when instream
levels to protect water quality should be less than 0.1 mg/l.
Effluent Monitorina
1.TSS-solids are problematic in High Rock Lake, however,the frequency of monitoring may be dropped to 2/month
.based on PPG's compliance record.
2. Fecal Coliform-though the facility is only 10%domestic and there is no evidence that the wastewater contains no
fecal coliform. PPG's chlorine use is excessive. PPG's average daily chlorine levels of 0.4 mg/are toxic. PPG
should monitor for fecal colonies before and after chlorination and take steps to reduce chlorine levels. Please refer
to the chlorine letter which was sent to domestic facilities.
3,4. Copper and Chromium- monitoring was recommended due to the poor compliance record for toxicity; it is likely
that toxicity failures are due to excessive chlorine use. Quarterly monitoring is recommended. Data will be reviewed
after a year and monitoring may be dropped.
1. Frequency- monitoring should be done during the months of June- October;conventional parameters should be
monitored weekly and nutrients and chlorophyll-a on a monthly basis.
2.Sampling Time-samples may be taken prior to 9-30 am
3. Chlorophyll-a - North Potts Creek and High Rock Lake are eutrophic. A management plan for High Rock Lake and
its tributaries is under development. Nutrient limits may be required upon completion of the report. PPG's effluent
data indicates TP levels of 2 mg/l and TN levels of 10- 15 mg/l. These levels of nutrients are similar to domestic
wastewater and ample to innoculate algal blooms. Chlorophyll-a sampling should remain in the permit.
4. Fecal ColHorm (winter) -okay to drop
5. TKN, NH3-N, and NOx -as discussed above, significant levels of nitrogen have been observed in the effluent and
monitoring is required given the eutrophic nature of the receiving stream.
If you have questions regarding these comments, please let me know.
CC'. Karla Sanderson j
Winston-Salem Regional Office