NCD003446721_20060809_Celeanse Corporation - Shelby Fiber_FRBCERCLA SAP QAPP_Monitored Natural Attenuation Demonstration Project Data Report - Quarterly Sampling 2004 - 2006-OCR

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NCDENR
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director
Mr. Ken Lucas
Remedial Project Manager
Division of Waste Management
August 9, 2006
Superfund Remedial and Site Evaluation Branch
Waste Management Division
US EPA Region IV
61 Forsyth Street, 11 th Floor
Atlanta, Georgia 30303
RE: Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #8 (1 st Quarter 2006)
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
The North Carolina Department of Environment and Natural Resources (NC DENR) Superfund
Section has received the Monitored Natural Attenuation Demonstration Project.Data Report for
Quarterly Sampling Event #8 (I'' Quarter 2006) for the Celanese Corporation National Priorities
List (NPL) Site. The NC DENR Superfund Section has reviewed this document and offers the
following attached comments,
The NC DENR Superfund Section appreciates the opportunity to comment on this document. If
' you have any questions or comments, please feel free to contact me at [phone].
Attachment
Sincerely, 12i&~so~~---• -
Environmental Engineer
NC DENR Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone [phone] I FAX [phone] I Internet http://wastenotnc.org
An Equal Opportunity I Affinnative Action Employer-Printed on Dual Purpose Recycled Paper
Mr. Ken Lucas
August 9, 2006
Page I
• •
Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #8 (1 st Quarter 2006)
Celanese Corporation NPL Site
Table of Contents
I. Please correct the Table of Contents to reflect Section 4.2.1 -Ethylene Glycol in the
Vicinity of the Former Source Area and Section 4.2.6 -Summary.
2. Please correct the List of Figures in the Table of Contents to indicate that the title of
· Figure 4-6 is Groundwater Analytical Results -Nitrate-Nitrogen -March 2006
Section 1.0 Introduction
3. Please correct the second sentence of the second paragraph of Section 1.0 to state
"Celanese Corporation bought the facility in 1983 ... "
Section 4.2.1 Ethylene Glycol in the Vicinity of the Former Source Area
4. Please revise the frequency of detection for groundwater monitoring well 0-25 in the
table included in Section 4.2. i to indicate "4/9".
Table 4-1 Summary of Selected Natural Attenuation Indicator Parameters
5. Please correct Table 4-1 to indicate that 0.79 milligrams per liter (mg/L) nitrate was
observed at background monitoring well U-38.
Appendix D Concentrations vs. Time Water Quality Plots
6. Please revise Appendix D to include the notes regarding the use of hollow data points for
results at the detection limit and the use of a dashed line to represent data trends using
linear regression throughout Appendix D.
7. Please revise the concentrations vs. time water quality plots for groundwater wells CC-
33, IT-6, IT-SR, IT-9, J-29, K-28, N-29, and V-65 to include the !st Quarter 2006 data
points.
8. · Please revise the concentrations vs. time water quality plots for groundwater wells IT-I
through IT-5 and IT-7 such that hollow data points are used for all results at the detection
limit. The remainder of Appendix D should be checked to verify that this technique has
been used consistently throughout Appendix D.
Re: Shelby -request for modification of groundwater sampling proc ...
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\
I of 2
• Subject: Re: Shelby -request for modification of groundwater sampling procedure re -Document
Control Number: 0265B-22 l
From: [e-mail]
Date: Mon, 07 Aug 2006 15:06:02 -0400
To: "Glover, Everett" <[e-mail]>
CC: "Dahlgren, Bryon" <[e-mail]>, [e-mail], Dave
Mattison <[e-mail]>, "Carter, PEM, Ticona/US" <[e-mail]>,
"Simpson, Steve_n M., RK.H/US" <[e-mail]>
Everett:
I 1ve have reviewed the attached memo and spoken to Dave Jenkins. I
concur with the modification to the sampling procedure.
Good Luck
Kenneth A. Lucas
Remedial Project Manager
Superfund Remedial Site Evaluation Branch
U. 8. Environmental Protection Agency, R4
Sam Nunn -Atlanta Federal Center
61 Forsyth Street
Atlanta, GA 30303
phone, 404-562-8953
fax , 404-562-8788
11Glover,
Everett 11
<Everett.Glover@
earthtech.com>
08/07/2006 02,07
PM
Ken Lucas/R4/USEPA/US@EPA, Dave
Jenkins/R4/USEPA/US@EPA, Dave
Mattison
<[e-mail]>
11 Carter, PEM, Ticona/US"
<[e-mail]>
11 Simpson, Steven M., RKH/US 11
To
cc
< steven.simpson@celaneseacetate.c
om>, 11 Dahlgren, Bryon11
<[e-mail]>
Subject
Shelby -request for modification
of groundwater sampling procedu
re -Document Control Number:
0265B-221
This email is written in response to an August 4, 2006, telephone
conversation between Dave Jenkins, U.S. Environmental Protection Agency
(EPA}, and Everett Glover and Jeff Peterman. Earth Tech Incorporated
{Earth Tech). During the conversation, Earth Tech requested a
8/9/2006 8:18 AM
Re: Shelby -request for modification of groundwater sampling proc ...
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modification to the Low-Flow Purging methodology that is described in
\ the "Work Plan for DPT/Monitoring Well Installation and Quarterly
Groundwater Sampling" (Work Plan), dated February 2006. The attachment
provides a summary of the telephone conversation including a brief site
background, description of the requested modification, and reasoning for
the requested modification. The modification was conceptually agreed
upon during the call.
2 of2
Please note that the analytical results obtained using the requested
modification will be compared to historic results to evaluate its
effect. If the results are relatively unchanged, the previous
methodology will be considered sufficient for obtaining a representative
sample and the modification will be discontinued. If the results are
"significantly" different, a determination will be made whether to
continue using the modification. In either case, the results will be
submitted to your office for review and comment.
We are scheduled to begin the third quarter sampling on Tuesday, August
15, 2006, and, if possible, would like to implement the requested
modification during this event. Therefore, your timely response would be
greatly appreciated. If you have questions, please contact me at the
number below or Jeff Peterman at [phone]. Talk with y'all later.
ewg
<<Shelby WP Mod Low Flow .dOC>>
Everett W. Glover, Jr. P.E.
Senior Program Director
Earth Tech
1455 Old Alabama Road, Ste. 170
Roswell, Georgia 30076
phone, [phone]
fax: [phone]
cell, [phone]
email: [e-mail](See attached file: Shelby WP Mod
Low Flow .doc)
!Shelby WP Mod Low Flow .doc
I I
Content-Type: application/msword
Content-Encoding: base64
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8/9/2006 8:18 AM
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Request for Work Plan Modification to Low Flow Purge Methodology
Celanese Fibers Operations Site -Shelby, North Carolina
Earth Tech Project No. 79750
Document Control Number: 0265B-221
Background
Earth Tech has performed two groundwater sampling events at the referenced site since March
2006. The sampling is generally performed in accordance with the low-flow procedure in the
referenced Work Plan with the exception that the maximum allowable drawdown (0.2 feet)
prescribed in the Work Plan is routinely exceeded because of the low well flow conditions at the
site.
The sampling is performed using peristaltic pumps at the lowest practical revolutions per minute to
minimize the groundwater flow rate. The estimated flow rate is between 60 to 80 milliliters per
minute. At these flow rates, drawdowns between 2 to 6 feet are routinely observed in the wells.
Modification
Because of the drawdowns that are observed during well purging, Earth Tech requests that the
following additions be made to the low flow procedures described in Section 5.1.3 in Appendix D of
the Work Plan:
A 1) Perform a pre-purge of the well the day before the well is scheduled to be sampled. The pre
-purge will include the following:
A 1 a) Measure the depth to water using an electronic water level tape or interface probe
as appropriate.
A1b) Using a disposable HOPE bailer, remove the water in the well casing to within
approximately 1 to 2 feet of the top of the screen.
A 1 c) Allow the water level in the in the well to recharge overnight to a minimum of 10 feet
above the top of the screen, if practical, before purging and sampling.
A2) Purge and sample the well according to the procedures described in Section 5.1.3 in
Appendix D of the Work Plan:
A3) During purging of the well, monitor the drawdown in the well to determine.if the water level
drops into the screened interval. These data will be used in evaluating the validity of the
sample if the results are significantly different from previous results.
Reasoning for Modification
The modification is requested so that: 1) concerns regarding drawdowns exceeding 0.2 feet can be
minimized; 2) the sampling procedure will be better suited to the low flow well conditions at the site;
3) the groundwater samples will be as representative of groundwater conditions as practical; and
4) the sampling can be in performed in compliance with the established procedures.
Shelby WP Mod Low Flow 8/9/2006
• • ® EarthTech
A tqca International Lid. Company
June 29, 2006
M:r. Kt.:tmcth Lucas
Remedial Project Manager
U.S. Environmental Protection Agency
61 Forsyth St. SW
Atlanta, Georgia 30303
Subject:
Dear Mr. Lucas:
Celanese Fiber Operations Site -Shelby, North Carolina
Letter of Transmittal -MNA Report #8
Earth Tech Project No. 79750
Document Control Number: 026S13-217
1455 Old Alabama Road
Suite 170
Roswell, GA 30076
Please find enclosed two copies of Monitored Natural Attenuation (MNA) Demonstration Report
#8 for the Celanese/ Ticona Shelby facility. This report presents the results of the sampling
event completed in March 2006. The primary purpose of this report is as a data update
subsequem to the assessment presented in the previous MNA report.
P 770.990.1400
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earthtech.com
Discussions with EPA, as well as comments provided in response to recent documents have
included requests for additional data supplements tu better define the ethylene glycol plume and
the effectiveness oi'MNA as a remedial alternative. We continue to work on implementing these
requests :md will provide the results of this work in subsequent repons as it becomes available.
l·iowc,·cr, these findings arc not yet available and arc beyond the scope of this March 2006 data
rtp•xt. In addition to continued monitoring, on~going ac~ivitics for suhsequenr reporting include
development of both conceptual and quantified site models and field effo11s including DPT
investigations and the addition of new permanent groundwater monitoring locations for the use of
bct,er defining the full extent of the plume. Field work for installation of the DPT points is
scheduled to be performed in the near li.:ture, and we anticipate having data from the
supplemental monitoring we] Is to report no later than the I I'" quarterly event in the fourth quarter
2006. .
If you have questions about the data presented or future activities, please contact us.
Sincerely,
Earth Tech, Inc.
Cp~/JJ. ~.yv
Everett W. Glover, Jr. P.E. ·
·~·
ProJcct Manager Project Engineer
• ® EarthTech
A tqco International Ltd. Company
cc: Dave Mattison, NCDENR
Steve Simpson, CNA Holdings, Inc.
PEM Carter, Ticona Shelby
•
•
@EarthTech
A tqca International Ltd. Company
June 27, 2006
Mr. Kenneth Lucas
Remedial Project Manager
U.S. Environmental Protection Agency
61 I'orsyth St. SW
Atlanta, Georgia 30303
•
1455 Old Alabama Road
Suite 170
Roswell, GA 30076
{o)§@~D\Yleg~
U7J JUN 2 8 2006 lW
SUPERFUNO SECTION
Subject: Celanese Fiber Operations Site -Shelby, North Carolina
Response lo EPA Comments on MNA Report #7
Earth Tech Project No. 79750
Document Control Number: 026SB-2 I 6
Dear Mr. Lucas:
This purpose of this letter is to respond to EP;\'s comments on the referenced document
which ,,,ere provided through your e-mail to Bryon Dahlgren. A copy of the comments is
al1.ached for reference. We provide specific responses below.
Response to Preliminary Comments:
We appreciate the opportunity to continue with the monitored natural attenuation (MNA)
demonstration. We arc confident that the 1i111e provided by this extension will allow us to
complete the additional investigation activities required to define the plume conditions and
fi.dly demonstrate the effectiveness ofMNA for this site. One of the requirements for
continued demonstration was the maintenance of the Outer Tier in a state of readiness for
operation. Our investigation into the Outer Tin indicates that we can not confirm the state of
readiness at this time. 1-Iowever: we are investigating it and will provide additional
information when it is available. Initial inspections indicate that the wells are in working
order.
In regard to perceived contradictions within the report, we do not agree that the referenced
statements are exclusive. We do agree tint certain wells close to the Inner Tier exhibited a
period ofinstabiEty following the deactivation of these wells. As EPA has noted in other
comments, the:--e changes in conditions at wells near the former extraction zone arc expected.
Ho\vever, the changes noted at these wells \vcrc not reflected in any similar changes in wells
located further away from the Inner Tier. Thus there is no indication that the overall extent or
P 770.990.1400
F 770.649.8721
earthtech.com
I
• • ® EarthTech
A "tlJCO International Ltd. Company
magnitude of the plume has increased and an interpretation ofa stable plume is supported by
the data. Further, all of the wells which demonstrated increases after the shut down of the
_Inner Tier have shown steady declines after the initial increase. These findings further
support the conclusion of a temporary re-equalization within an otherwise stable plume.
We understand that additional information is required to complete the demonstration of
effectiveness of MNA for this site. It is our interpretation that a strong indication of the
plume's boundary and stability is provided by the current monitoring network. However, we
agree there are gaps in the existing network which need to be addressed to establish that the
cuncnt interpretation is accurate for the entire plume.
We are developing both a conceptual and quantitative model to define the site and plume.
We are also planning to implement the DPT study and add additional wells to till the gaps in
the existing network. Data gathered from these activities will be included in the site models
and assessments as the data become available.
In regard to the ponds, we have considered their impact on the site groundwater contours.
Groundwater elevations reported in wells between and around the ponds have remained
signi licantly below the levels of the ponds and consistent with sunounding wells located
further from the ponds. In the development of the groundwater flow model the ponds were
taken into account. In order to calibrate the model, a very low transmissivity was required for
the soils under the ponds indicating that even though there is no known liner in the ponds,
there appears to be minimal leakage from the ponds to the underlying groundwater. Thus, the
field observations support the existing ,,~·oundwater contour interpretations.
Response to General Comments:
Comment 1:
We are developing the concept model as requested as the basis for developing a numerical
flow model. Once models and other data gathering arc complete, we will be able to provide
detailed answers to the questions listed.
Comment 2:
We agree that the plume should react to the shut down of the Inner Tier. Data collected so for
indicates that this response has been observed and the ethylene glycol concentrations in the
area arc now declining. The Outer Tier wells are not part of the cunent monitoring program.
An appropriate monitoring plan will need to be established once a long-term monitored
natural attenuation program is established. Based on the location of the plume, the use of
Outer Tier wells as sentinel points may be appropriate.
Comment 3:
It is our interpretation based on cunent data that there is no potential for the ethylene glycol
plume to come within close proximity of the Outer Tier. We are cuncntly completing tasks
designed to complete our understanding of the plume. Once this understanding is established
a long-term monito:·ing plan should be established. However, we do not believe it is
appropriate to establish a long-term plan before this understanding is reached.
• •
@EarthTech
A tqca International ltd. Company
Comment 4:
Current data indicates that the plume is not progressing toward the Outer Tier. As the
additional planned work as presented in the recently approved Work Plan is completed, we
will provide the results to EPA.
Comment 5:
The proposed DPT locations were based on an effort to capture the main flow direction
expected for the ethylene glycol plume. Well W-23 currently serves as a non-detect sentinel
location to the southeast. The concentration at well 0-25 is declining. The proposed DPT
locations are in the pathway of groundwater flow without sentinel points prior to the vicinity
of the Outer Tier. In our assessment, currently planned points are the most appropriate
locations for complctmg the definition of the plume. However, we would suggest that the
study could be supplemented by sampling well X-32 for ethylene glycol.
Once the initial DPT study is complete we will do a thorough review of the updated data. If
the plume is not adequately defined by the data collected, we will remobilize to establish
additional DPT points as needed. Otherwise, we will proceed with the plan for installation of
pennanent monitoring locations.
Comment 6:
The current scope of work docs not include any additional potentiometric points other than
points associated with the DPT investigation and subsequent monitoring well installation. As
mentioned previously, assessment of the potentiometric data associated with the ponds and
nearby monitoring wells has indicated that the current groundwater now interpretation is
accurate.
Comment 7:
The model has been calibrated based on the understanding of unlined ponds. The extremely
low transmissivity required to accurately calibrate the model to match field data indicates that
the ponds produce a minimal impact on groundwater flow.
Response to specific comments/corrections:
We agree with the corrections identified in comments I through 15. Updates and corrections
suggested in these comments will be implemented in future reports. A revised complete site
assessment utilizing all available data will also be prepared in early 2007.
Slug-out results for well W-23 are attached. Updated concentration vs. time plots and
historical data tables will be provided in the MNA event #8 report. These updates will
include the requested changes.
Thank you for providing these comments. Please contact us if you need additional
information.
@EarthTech
A 1:qca International Ltd. Company
Sincerely,
Earth Tech, Inc.
Everett W. Glover, Jr. P.E.
Project Manager
•
cc: Dave Mattison, NCDENR
Steve Simpson, CNA Holdings, Inc.
PEM Carter, Ticona Shelby
•
Bryon Dahlgren
Project Engineer
4WD-SRSEB
• • UNITED ST.!\ TES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
A; LANT A F[[J[f1AL CEN fH1
ti' roRSYTrl STREd
'•T! ..A.i-JT,-\ CiEORGIA 30]03-8960
Mr Sieve Simpson, Authorized Agent
clo Celanese Corporation
2525 Blacksburg Road
Grover, North Carolina 28073
Subject: Monitored Natural Attenuation Demonstration Pro1ect
Data Report for Quarterly Sampling Event #7
Celanese Corporation National Priorities List (NPL) Site
Shelby, Cleveland County, NC
Dear Mr. Simpson:
The United States Environmental Protection Agency (EPA) has reviewed the Monitored
Natural .tHtenuation Demonstration Project Data Report for Quarterly Sampling Event #7 (4'"
Quarter 2005) for the Celanese Corporation National Priorities List (NPL) Site. Over the pa.pt two
years the monitoring program, and has provided much data in a well drafted series of sample
event reports. One underlying purpose of this series of Monitored Natural Attenuation (MNA)
repor1s is to demonstrate that the pumping wells ol the Inner and Outer Tier can remain off, and
that the pump and treat operation need not be resumed. EPA agrees that the pumps can remain
off for the time being, however, not for the reasons presented in Section 5 of the report, and only
under the conditions that the long-term monitoring program is adequate, that the pumps in the
Outer Tier are maintained and remain ready for operation.
As a report of the results of sampling efforts at this site, this is an excellent report.
However, regarding policy issues and plans for future efforts, various statements in the repor1
seem to conflict with other statements in tl1e same report, and sometimes seem to conflict with
basic EPA goals and guidelines. For example, the first paragraph of Section 5 includes
statements about evidence for a stabilized plume. Yet the first sentence of the second paragraph
of Section 5 includes statements about the evidence of an unstable plume which is responding to
the shut down of the Inner Tier wells, and also contains statements about contamination moving
from the source are to nearby down gradient areas.
As stated earlier, the MNA reports have presented much useful data, however, the
conclusions in Section 5 are written as if just the existence of natural attenuation processes is
enough to constitute a remedial measure for this site. They are not; the conclusions in Section 5
do not answer the questions regarding where the plume is and where it will be relative to the
Inner Tier wells, the Outer Tier wells and the property boundary.
i• ..
• •
Once the data from the upcoming DPT sampling is available and additional data
regarding the influence of the on-site ponds, it would be useful to develop a concept model which
describes the site, the distribution of contamination, factors which influence directions of ground
water flow and contaminant migration, etc. The concept model should describe what happened,
and be a framework for what is going to happen.
Regarding the on-site ponds, until recently, EPA had been under the impression that the
on-site ponds were lined. During a recent conversation with Everett Glover, it was revealed that
the ponds are not lined. Since they are not lined, there are mounds on the water table beneath
these ponds. The groundwater elevation contours shown on all water level maps produced for
this site show the contours drawn beneath the ponds as if they don't exist. Therefore the
groundwater flow directions shown on the maps may be wrong. The size and affect of the
mounding has not been quantified. This is a major issue which must be resolved before natural
attenuation can be properly evaluated. Confidence in the ground water flow directions is
essential to be able to evaluate degradation versus distance based on the knowledge of which
wells are connected by which flow paths.
Additional comments are provided in the enclosure to this letter, Please address ihese
comments as you submit the next monitoring report. If you have any questions or comments,
please feel free to contact me at [phone].
Enclosure
\i/rely,
~I;::_;-\.
Kenneth A. Lucas
Remedial Project Manager
Waste Management Division
cc: David Mattision, NC DENR Supcrfund Section
Everett W. Glover, Jr., PE, Earth Tech, Inc.
2
•
EPA Comments
Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #7 (4th Quarter 2005)
Celanese Corporation, National Priorities List (NPL) Site.
GENERAL COMMENTS
1. A concept model should be developed which describes the site, the distribution of
contamination, factors which influence directions of ground water flow and contaminant migration,
etc. The primary concerns are:
• Is Natural Attenuation working fast enough to prevent the residual contamination from
moving away from the vicinity of the Inner Tier wells now that the pump in these wells
have been turned off?
• Is Natural Attenuation working fast enough to prevent the down gradient edge of the
plume from reaching the Outer Tier of wells again?
• Is Natural Attenuation working fast enough to prevent the down gradient edge of the
plume from migrating beyond the property boundary?
• If the answer to any of the questions above is "no", should some or all of the pumps be
turned on again?
Resolution of these questions should evolve from the development of the concept model. The
conclusions and recommendations Section, Section 5, should focus on the questions above. Not
the increase in microbial activity.
2. It would be surprising if the ethylene glycol plume was not expanding after the system of
capture wells was turned off. The report shows that water level elevations have returned to
natural levels, so movement toward the natural ground water discharge areas should be
expected. Again, proof is lacking either way because few monitoring points exist. Additionally,
the Outer Tier wells must be monitored appropriately to serve as effective sentinel wells, and that
the Outer Tier wells are maintained so that they can be returned lo service if necessary.
3. If the Outer Tier wells are being maintained so that they are ready to be turned on with
lillle notice, and if these wells are being sampled at appropriate intervals to serve as sentinel
wells, then the pumps can remain off. If the plume gets within close proximity of the the Outer
Tier wells, then pumping in the both Inner and Outer Tiers of wells should be resumed. A long-
term monitoring program for the site should be submitted as soon as possible.
4. Section 4.2.5.4, p.17 lists a number of observations which support the occurrence of
biological degradation of ethylene glycol. This is all good evidence that the processes are
occurring, but unfortunately, proof of the effectiveness of these processes is limited as
degradation rates have not been determined. It must be determined if the rates of degradation
are sufficient to contain the plume within the Outer Tier.
5. Natural attenuation is working to some degree at this site, but the line of evidence based
on contaminant degradation versus distance from the source is not convincing. The planned DPT
sampling investigation might help resolve this problem, but as proposed the proof may be
incomplete. The Inner Tier wells were installed in a line which roughly trends north-south across
the source area. After years of pumping, contamination had been isolated into a north-south
trending mass. With the pumps off, contamination is allowed to fan out from the pumping centers
and move toward the natural ground water discharge areas under the natural hydraulic gradient.
• •
The water level contours show that flow paths from the Inner Tier Wells to natural discharge
areas may occur in any direction 180' from the source area, not simply along the one flow arrow
shown on Figure 4-12. The width of the resulting ethylene glycol plume is unknown, but Figure 4-
12 shows that none of the 3 proposed DPT locations are along what might be expected to be the
centerline of the plume from monitoring well V-23. This comment was not included in the review
of the DPT work plan dated February 20, 2006. Similar comments regarding location of a plume
using a dynamic work plan were presented concerning ground water contamination near
monitoring well F-55, but these were not repeated or specifically addressed to DPT-5, 6 & 7
shown on Figure 1 of lhe work plan. The three proposed DPT holes probably will provide some
useful information, but until the location of the plume in the area between N-29 and W-23 is better
known, there will be some uncertainty regarding the effectiveness of natural attenuation. If
possible, the DPT investigation should focus not on installing 3 DPT holes, but focus on defining
a profile across the plume between W-23 and N-29.
6. Water quality samples are not needed to improve the accuracy of the water leve! contour
maps, so additional monitoring points may need to be shallow, temporary, small-diameter
piezometers only. 1-inch PVC with short screens installed a few feet below the water table
around the ponds probably would be sufficient. Water level elevation data from the new
piezometers should be collected with water level measurements from the existing monitoring
wells and staff gauge data to create a water level contour map. Based on the topography,
distances to the streams and the locations of the ponds, the resulting new water level contours
could alter our concept of ground water flow directions and contaminant migration by 90'.
7. Regarding the modeling effort, EPA guidelines are clear that regulatory decisions
regarding Monilored Natural Attenuation must be based in field observations, not modeled
predictions or calculations. If the model makers don't already know that the ponds may be
leaking, the models won't be a useable representation of the ground waler flow system.
SPECIFIC COMMENTS/CORRECTIONS
Section 1.2 OU-2 Remedial Actions
1. Please correct the first sentence of Section 1.2 to slate "For OU-2, a 100% remedial
design and remedial action work plan was submilled in September 1990 ..
Section 4.2.1 Ethylene Glycol in the Vicinity of the Former Source Area
2. Please correct the second sentence of the fifth paragraph of Section 4.2.1 to state "the
concentrations vs. time waler quality plots (Appendix E) show the concentration changes
since 1981 and during the MNA demonstration period."
3. In accordance with the information provided in Appendix E and Appendix F of this report,
please correct the last sentence of the data interpretation for extraction well IT -9 in the
table included in Section 4.2.1 to state "Ethylene glycol was not detected during the
most recent sampling event."
4. Please revise the data interpretations for monitoring wells N-29, 0-33, Tl-1, and U-38 in
the table included in Section 4.2.1 lo state "Ethylene glycol has not been detected in this
well since monitoring began in September 2001."
5. In accordance with the information provided in Appendix E and Appendix F of this report,
please delete the second sentence of the data interpretation of monitoring well W-23 in
the table included ,n Section 4.2.1.
2
•
Section 4.2.2 Ethylene Glycol in the F-55 Area
6. In accordance with the information provided in Appendix E and Appendix F of this report,
· please correct the second sentence of Section 4.2.2 to state "Ethylene glycol was first
analyzed and detected at 120 mg/Lat well F-55 in August 1992 and again analyzed
and detected at 155 mg/Lin September 2001.
Section 4.2.5.2 Evidence of Contaminant Degradation with Time
7. Please correct the last sentence of the Sen's Test Comments for groundwater well lT-4 to
state "Not detected for two recent consecutive events which indicates attenuation of
ethylene glycol at this well location."
8. Please correct the last sentence of the Sen's Test Comments for groundwater well IT-5 to
state "Not detected for two recent consecutive events which indicates attenuation of
ethylene glycol at this well location."
9. Please correct the last sentence of the Sen's Test Comments for groundwater well lT-9 to
stale "Nol detected for most recent sampling event."
Section 4.2.5.4 Evidence of Biological Activities
10. Please correct the title of Section 4.2.5.4 to slate "Evidence of Biological Activities".
Table 2-2 Summary of Chemical Data
11. Please correct Table 2-2 to provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling.
Figure 4-4 Groundwater Field Measurements -pH -October 2005
12. Please correct Figure 4-4 to provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling.
Figure 4-5 Groundwater Field Measurements -Conductivity -October 2005
13. Please correct Figure 4-5 lo provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling.
Figure 4-10 Groundwater Analytical Results -Methane -October 2005
14. Please revise Figure 4-10 to indicate that the values given for methane at groundwater
monitoring wells J-29, 0-33, Tl-1, U-38, and W-23 should be presented as less than (i.e.,
<) the value presented.
Appendix B Low-Flow Groundwater Sampling Logs and Water Level Measurements
15. Please revise the cover sheet for Appendix 8 to indicate that Low-Flow Groundwater
Sampling Logs are included for wells C-49, J-59, P-58, T-35. KK-55, LL-110, NN-105,
and X-32 in support of 1.4-dioxane investigation activities. Additionally, since monitored
natural attenuation (MNA) parameters are being collected at these wells, please address
the question as to whether this additional data should be included to supplement the data
already contained in this report.
3
•
Appendix D Slug Test Data
16. The slug test data resulls for the slug-oul lest al groundwaler monitoring well W-23 was
· inadvertently omilted from Appendix D. Please correct lhis oversight.
Appendix E Concentrations vs. Time Water Quality Plots
17. Please revise Appendix E to include the notes regarding the use of hollow data points for
results at the detection limit and the use of a dashed line to represent data trends using
linear regression throughout Appendix E.
18. Please revise the concentrations vs. time water quality plots for extraction wells IT-1
through IT-5 such that hollow data points are used for all results at lhe delection limil.
The remainder of Arpendix E should be checked to verify lhat this technique has been
used throughout Appendix E.
Appendix F Summary of Historical Data (Data Source of Appendix E)
19. Please revise the formatting of the tables included as Appendix F such thal the column
headings are consistent for each entry (i.e., one date per column).
4
•
•
Slugtest -Slugout -W-23 6/20/05
Ci\lA!Ticona Shelb\/, NC
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• • UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
ATLANTA FEDERAL CENTER
61 FORSYTH STREET
ATLANTA, GEORGIA 30303-8960
, JUN 1 2006
4WD-SRSEB
Mr. Steve Simpson, Authorized Agent ·
c/o Celanese Corporation
2525 Blacksburg Road
Grover, North Carolina 28073
Subject: Monitored Natural Attenuation Demonstration Project
Data Report for Quarterly Sampling Event #7
Celanese Corporation National Priorities List (NPL) Site
Shelby, Cleveland County, NC
Dear Mr. Simpson:
The United States Environmental Protection Agency (EPA) has reviewed the Monitored
Natural Attenuation Demonstration Project Data Report for Quarterly Sampling Event #7 (4'h
Quarter 2005) for the Celanese Corporation National Priorities List (NPL) Site. Over the Pil-,llt two
years the monitoring program, and has provided much data in a well drafted series of sample
event reports. One underlying purpose of this series of Monitored Natural Attenuation (MNA)
reports is to demonstrate that the pumping wells of the Inner and Outer Tier can remain off, and
that the pump and treat operation need not be resumed. EPA agrees that the pumps can remain
off for the time being, however, not for the reasons presented in Section 5 of the report, and only
under the conditions that the long-term monitoring program is adequate, that the pumps in the
Outer Tier are maintained and remain ready for operation. · ·
As a report of the results of sampling efforts at this site, this.is.an excellent report.
However, regarding policy issues and'plans for future efforts, various statements in the report·
seem to conflict with other statements in the same report, and sometimes seem to conflict with
basic EPA goals and guidelines. For example, the first paragraph of Section 5 includes
statements about evidence for a stabilized plume. Yet the first sentence of the second paragraph
of Section 5 includes statements about the evidence of an unstable plume which is responding to
the shut down of the Inner Tier wells, and also contains statements about contamination moving
from the source are to nearby down gradient areas.
As stated earlier, the _MNA reports have presented much useful data, however, the
conclusions in Section 5 are written as if just the existence of natural attenuation processes is
enough to constitute a remedial measure for this site. They are not; the conclusions in Section 5
do not answer the questions regarding where the plume is and where it will be relative to the
Inner Tier wells, the Outer Tier wells and the property boundary.
Internet Address (UAL) • http://www.epa.gov
Recycled/Recyclable • Prin!ed with Vegetable Oil Based Inks on Recycled Paper (Minimum 30% Poslconsumer)
•
Once the data from the upcoming DPT sampling is available and additional data
regarding the infiuence of the on-site ponds, it would be useful to develop a concept model which
describes the site, the distribution of contamination, factors which infiuence directions of ground
water flow and contaminant migration, etc. The concept model should describe what happened,
and be a framework for what is going to happen.
Regarding the on-site ponds, until recently, EPA had been under the impression thafthe
on-site ponds were lined. During a recent conversation with Everett Glover, it was revealed that
the ponds are not lined. Sjnce they are not lined, there are mounds on the water table beneath·'·,, • .,.
the~e ponds. The groundwater elevatio_n contours _shown on all water level maps produced for
this site show the contours drawn beneath the ponds as if they don't exist. Therefore the
groundwater flow directions shown on the maps may be wrong. The size and affect of the
mounding has not been quantified. This is a major issue which must be resolved before natural.
attenuation can be properly evaluated. Confidence in the ground water fiow directions is -
essential to be able to evaluate degradation versus distance based on the knowledge of which
wells are connected by which flow paths.
Additional.comments are provided.in the.enclosure to this letter,-Please address these.-
comments as you submit the next monitoring report. If you have any questions or comments,
please feel free to contact me at [phone].
Enclosure
~~~
Kenneth A. Lucas
Remedial Project Manager
Waste Management Division
cc: David Mattision, NC DENR Superfund Section
Everett W. Glover, Jr., PE, Earth Tech, Inc.
2
.i;,-. ......
• ••
EPA Comments
Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #7 (4th Quarter 2005)
Celanese Corporation, National Priorities List (NPL) Site.
GENERAL COMMENTS
1. A concept model should be developed which describes the site, the distribution of
contamination, factors which influence directions of ground water flow and contaminant migration,
etc. The primary concerns are:
• Is Natural Attenuation working fast enough to prevent the residual contamination from
moving away from the vicinity of the Inner Tier wells now that the pump in these wells
have been turned off?
• Is Natural Attenuation working fast enough to prevent the down gradient edge of the
plume from reaching the Outer Tier' of wells again? .. , · · ·· '· · · · '
• Is Natural Attenuation working fast enough to prevent the down gradient edge of the
plume from migrating beyond the property boundary?
• If the answer to any of the questions above is "no", should some or all of the pumps be
turned on again?
Resolution of these questions should evolve from the development of the concept model. The
conclusions and recommendations Section, Section 5, should focus on the questions above. Not
the increase in microbial activity. · · ·-a
2. It would be surprising if the ethylene glycol plume was not expanding after the system of
capture wells was turned off. The report shows that water level elevations have returned to
natural levels, so movement toward the natural ground water discharge areas should be
expected. Again, proof is lacking either way because few monitoring points exist. Additionally,
the Outer Tier wells must be_ monitored appropriately to. serve as effective sentinel wells, and that
the Outer Tier wells are maintained so that they can be returned to service if necessary.
3. If the Outer Tier wells are being maintained so that they are ready to be turned on with
little notice, and if these wells are being sampled at appropriate intervals to serve as sentinel
wells, then the pumps can remain off. 'If the plume gets within close proximity of the the Outer
Tier wells, then pumping in the both Inner and Outer Tiers of wells should be resumed. A long-
term monitoring program for the site should be submitted as soon as possible. · ·
4. Section 4.2.5.4, p.17 lists a number of observations which support the occurrence of
biological degradation of ethylene glycol. This is all good evidence that the processes are
occurring, but unfortunately, proof of the effectiveness of these processes is limited as
degradation rates have not been determined. It must be determined if the rates of degradation
are sufficient to contain the plume within the Outer Tier.
5. Natural attenuation is working to some degree at this site, but the line of evidence based
on contaminant degradation versus distance from the source is not convincing. The planned DPT
sampling investigation might help resolve this problem, but as proposed the proof may be ·
incomplete. The Inner Tier wells were installed in a line which roughly trends north-south across
the source area. After years of pumping, contamination had been isolated into a north-south
trending mass. With the pumps off, contamination is allowed to fan out from the pumping centers
and move toward the natural ground water discharge areas under the natural hydraulic gradient.
•
The water level contours show that flow paths from the Inner Tier Wells to natural discharge
areas may occur in any direction 180° from the source area, not simply along the one fiow arrow .
shown on Figure 4-12. The width of the resulting ethylene glycol plume is unknown, but Figure 4-
12 shows that none of the 3 proposed DPT locations are along what might be expected to be the
centerline of the plume from monitoring well V-23. This comment was not included in the review
of the DPT work plan dated February 20, 2006. Similar comments regarding location of a plume
using a dynamic work plan were presented concerning ground water contamination near
monitoring well F-55, but these were not repeated or specifically addressed to DPT-5, 6 &-7
shown on Figure 1 of the work plan. The three proposed DPT holes probably will provide some, .
useful information, but until the location of the plume in the area between N-29 and W-23 is better
known, there will be some uncertainty regarding the effectiveness of natural attenuation. If
possible, the DPT investigation should focus not on installing 3 DPT holes, but focus on defining
a profile across the plume between W-23 and N-29.
6. Water quality samples ·are noi needed to improve the accur~cy of the water level contour
maps, so additional monitoring points may need to be shallow, temporary, small-diameter
piezometers only. 1-inch PVC with short screens installed a few feet below the water table
around the ponds probably would be sufficient. Water level elevation data from the new
piezometers should be collected with water level measurements from the existing monitoring
wells and staff gauge data to create a water level contour map. Based on the topography,
distances to the streams and the locations of the ponds, the resulting new water level contours
could alter our concept of ground water fiow directions and contaminant migration by 90°.
7. Regarding the modeling effort, EPA guidelines are clear that regulatory decisions
regarding Monitored Natural Attenuation must be based in field observations, not modeled
predictions or calculations. If the model makers don't already know that the ponds may be .
leaking, the models won't be a useable representation of the ground water flow system.
SPECIFIC COMMENTS/CORRECTIONS
Section 1.2 OU-2 Remedial Actions
1. Please coirect the first sentence of Section 1.2 to state "For OU-2, a 100% remedial
design and remedial action work plan was·submitted in September .1990 ... "
Section 4.2.1 · Ethylene Glycol in the Vicinity of th«l_Former Source Area
2. Please correct the second sentence of the fifth paragraph of Section 4.2.1 to state "the
concentrations vs. time water quality plots (Appendix E) show the concentration changes
since 1981 and during the MNA demonstration period."
3. In accordance with the information provided in Appendix E and Appendix F of this report,
please correct the last sentence of the data interpretation for extraction well IT-9 in the
table included in Section 4.2.1 to state "Ethylene glycol was not detected during the
most recent sampling event."
4. Please revise· the data interpretations for monitoring wells N-29, 0-33, Tl-1, and U-38 in
the table included in Section 4.2.1 to state "Ethylene glycol has not been detected in this
well since monitoring began in September 2001."
5. In accordance with the information provided in Appendix E and Appendix F of this report,
please delete the second sentence of the data interpretation of monitoring well W-23 in
the table included in Section 4.2.1.
2
• •
Section 4.2.2 Ethylene Glycol in the F-55 Area
6. In accordance with the information provided in Appendix E and Appendix F of this report,
· please correct the second sentence of Section 4.2.2 to state "Ethylene glycol was first
analyzed and detected at 120 mg/Lat well F-55 in August 1992 and again analyzed
and detected at 155 mg/Lin September 2001.
Section 4.2.5.2 Evidence of Contaminant Degradation with Time
7. Please correct the last sentence of the Sen's Test Comments for groundwater well lT-4 to
state "Not detected for two recent consecutive.events which indicates attenuation of
ethylene glycol at this well location."
8. Please correct the last senten·ce of the Sen's Test Comments for'groundwater well lT-5 to
state "Not detected for two recent consecutive events which indicates attenuation of
ethylene glycol at this well location."
9. Please correct the last sentence ·of the Sen's Test Comments for groundwater well lT-9 to
state "Not detected for most recent sampling event."
Section 4.2.5.4 Evidence of Biological Activities
10. Please correct the title of Section 4.2.5.4 to state "Evidence of Biological Activities".
Table 2-2 Summary of Chemical Data
11. Please correct Table 2-2 to provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling. ••
'
Figure 4-4 Groundwater Field Measurements -pH -October 2005
12. Please correct Figure 4-4 to provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling.
Figure 4-5 Groundwater Field Measurements -Conductivity -October 2005
13. Please correct Figure 4-5 to provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling. · •
Figure 4-10 Groundwater Analytical Results -Methane -October 2005
14. Please revise Figure 4-10 to indicate that the values given for methane at groundwater
monitoring wells J-29, Q-33, Tl-1, U-38, and W-23 should be presented as less than (i.e.,
<) the value presented.
Appendix B Low-Flow Groundwater Sampling Logs and Water Level Measurements
15. Please revise the cover sheet for Appendix B to indicate that Low-Flow Groundwater
Sampling Logs are included for wells C-49, J-59, P-58, T-35, KK-55, LL-110, NN-105,
and X-32 in support of 1,4-dioxane investigation activities. Additionally, since monitored
natural attenuation (MNA) parameters are being collected at these wells, please address
the question as to whether this additional data should be included to supplement the data
already contained in this report.
3
• •
Appendix D Slug Test Data
16. The ·slug test data results for the slug-out test at groundwater monitoring well W-23 was
· inadvertently omitted from Appendix D. Please correct this oversight.
Appendix E Concentrations vs. Time Water Quality Plots
17. Please revise Appendix E to include the notes regarding the use of hollow data points for
results at the detection limit and the use of a dashed line to represent data trends using
linear regression throughout Appendix E. ·
18: Please revise the concentrations vs. time water quality plots for extraction wells IT-1
through IT-5 such that hollow data points are used for all results at the deteciion limit.
The remainder of Appendix E should be checked to verify that this technique has been
used throughout Appendix E.
Appendix F Summary of Historical Data (Data Source of Appendix E)
19. Please revise the formatting of the tables included as Appendix F such that the column
headings are consistent for each entry (i.e., one date per column).
. .. , (
4
• . AV·••~ ~--.:;;;;;;;;;.;::;;.'~,: NCDE_N_R
•
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director Division of Waste Management
April 12, 2006
Mr. Ken Lucas
Remedial Project Manager
Superfund Remedial and Site Investigation Branch
Waste Management Division
US EPA Region IV
61 Forsyth Street, 11 th Floor
Atlanta, Georgia 30303
RE: Monitored Natural Attenuation Demonstrntion Project Data Report
Quarterly Sampling Event #7 ( 4th Quarter 2005)
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
The North Carolina Department of Environment and Natural Resources (NC DENR) Superfund
Section has received the Monitored Natural Attenuation Demonstration Project Data Report for
Quarterly Sampling Event #7 (4 th Quarter 2005) for the Celanese Corporation National Priorities
List (NPL) Site. The NC DENR Superfund Section has reviewed this document and offers the
following attached comments.
The NC DENR Superfund Section appreciates the opportunity to comment ori this document. If
you have any questions or comments, please feel free to contact me at [phone].
Attachment
13:t?µfi1~
David B. Mattison
Environmental Engineer
NC DENR Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone [phone] \ FAX [phone] \ Internet http://wastenotnc.org
An Equal Opportunity I Affirmative Action Employer-Printed on Dual Purpose Recycled Paper
Mr. Ken Lucas
April 12, 2006
Page I
•
Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #7 (4th Quarter 2005)
Celanese Corporation NPL Site
Section 1.2 OU-2 Remedial Actions
1. Please correct the first sentence of Section 1.2 to state "For OU-2, a I 00% remedial
design and remedial action work plan was submitted in September 1990 ... "
Section 4.2.1 Ethylene Glycol in the Vicinity of the Former Source Area
2. Please correct the second sentence of the fifth paragraph of Section 4.2.1 to state "the
concentrations vs. time water quality plots (Appendix E) show the concentration changes
since 198 I and during the MNA demonstration period.'.'
3. In accordance with the information provided in Appendix E and Appendix F of this
report, please correct the last sentence of the data interpretation for extraction well IT-9 in
the table included in Section 4.2.1 to state "Ethylene glycol was not detected during the
most recent sampling event."
4. Please revise the data interpretations for monitoring wells N-29, Q-33, TI-I, and U-38 in
the table included in Section 4.2. l to state "Ethylene glycol has not been detected in this
well since monitoring began in September 2001.'' ·
5. In accordance with the information provided in Appendix E and Appendix F of this
report, please delete the second sentence of the data interpretation of monitoring well W-
23 in the table included in Section 4.2.1. ·
Section 4.2.2 Ethylene Glycol in the F-55 Area
6. In accordance with the information provided in Appendix E and Appendix F of this
report, please correct the second sentence of Section 4.2.2 to state "Ethylene glycol was
first analyzed and detected at 120 mg/L at well F-55 in August 1992 and again
analyzed and detected at 155 mg/Lin September 2001.
Section 4.2.5.2 Evidence of Contaminant Degradation with Time
7. Please correct the last sentence of the Sen's Test Comments for groundwater well IT-4 to
state "Not detected for two recent consecutive events which indicates attenuation of
ethylene glycol at this well location."
Mr. Ken Lucas
April 12, 2006
Page 2
• •
8. Please correct the last sentence of the Sen's Test Comments for groundwater well IT-5 to
state "Not detected for two recent consecutive events which indicates attenuation of
ethylene glycol at this well location."
9. Please correct the last sentence of the Sen's Test Comments for groundwater well IT-9 to
. state "Not detected for most recent sampling event."
Section 4.2.5.4 Evidence of Biological Activities
10. Please correct the title of Section 4.2.5.4 to state "Evidence of Biological Activities".
Table 2-2 Summary of Chemical Data
. 11. Please correct Table 2-2 to provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling.
Figure 4-4 Groundwater Field Measurements -pH-October 2005
12. Please correct Figure 4-4 to provide the field indicator dat<) for groundwater monitoring
well F-55 from the time of sampling.
Figure 4-5 Groundwater Field Measurements -Conductivity -October 2005
13. Please correct Figure 4-5 to provide the field indicator data for groundwater monitoring
well F-55 from the time of sampling.
Figure 4-10 Groundwater Analytical Results -Methane-October 2005
14. Please revise Figure 4-10 to indicate that the values given for methane at groundwater
monitoring wells J-29, Q-33, TI-I, U-38, and W-23 should be presented as less than (i.e.,
<) the value presented.
Appendix B Low-Flow Groundwater Sampling Logs and Water Level Measurem·ents
15. Please revise the cover sheet for Appendix B to indicate that Low-Flow Groundwater
Sampling Logs are included for wells C-49, J-59, P-58, T-35, KK-55, LL-110, NN-105,
and X-32 in support of 1,4-dioxane investigation activities. Additionally, since
monitored natural attenuation (MNA) parameters are being collected at these wells,
please address the question as to whether this additional data should be included to
· supplement the data already contained in this report.
I
Mr. Ken Lucas
April 12, 2006
Page 3 ·
•
Appendix D Slug Test Data
•
16. The slug test data results for the slug-out test at groundwater monitoring well W-23 was
inadvertently omitted from Appendix D. Please correct this oversight.
Appendix E Concentrations vs. Time Water Quality Plots
17. Please revise Appendix E to include the notes regarding the use of hollow data points for
results at the detection limit and the use of a dashed line to represent data trends using
· linear regression throughout Appendix E.
18. Please revise the concentrations vs. time water quality plots for extraction wells IT-!
through IT-5 such that hollow data points are used for all results at the detection limit.
The remainder of Appendix E should be checked to verify that this technique has been
used throughout Appendix E.
Appendix F Summary of Historical Data (Data Source of Appendix E)
19. Please revise the formatting of the tables included as Appendix F such that the column
headings are consistent for each entry (i.e., one date per column).
• • &~-:~A -,~~ ---NCDENR
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director' Divisiqn of Waste Management
Mr. Ken Lucas
Remedial Project Manager
Superfund Branch
Waste Management Division
US EPA Region IV
61 Forsyth Street, 11 th Floor
Atlanta, Georgia 30303
March 30, 2005
RE: Monitored Natural Attenuation Demonstration Project Data.Report
Quarterly Sampling Event #2 (3rd Quarter 2004)
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
The Superfund Section of the North Carolina Department of Environment and Natural·Resources
(NC DENR) has received and reviewed the Monitored Natural Attenuation Demonstration
Project Data Report for Quarterly Sampling Event #2 (3rd Quarter 2004) for the Celanese
Corporation National Priorities List (NPL) Site. The Superfund Section offers the following
attached comments. ·
The Superfund Section of the NC DENR appreciates the opportunity to comment on this
document. If you have any questions or comments, please feel free to contact me at (9 I 9) 733-
2801, extension 349.
Attachment
Sincerely,
(j)~?>fL;tt:s
David B. Mattison
Environmental Engineer
NC Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone [phone] I FAX [phone] I Internet http://wastenotnc.org
An Equal Opportunity I Affinnative Action Employer-Printed.on Dual Purpose Recycled Paper
Mr. Ken Lucas
March 30, 2005
Page 1
• •
Monitored Natural Attenuation Demonstration Project Data Report
For Quarterly Sampling Event #2 (3 rd Quarter 2004)
Celanese Corporation NPL Site
Section 3.2.2 Discussion of Analytical Findings
I. Per the Revised Monitored Natural Attenuation Demonstration Project Data Report for
Quarterly Sampling Event #1 (2nd Quarter 2004), please revise the third sentence of the
fourth paragraph of Section 3.2.2 to define the United States Environmental Protection
Agency (US EPA) monitored natural attenuation (MNA) guidance document as Technical
Protocol for Evaluating Natural Attenuation of Chlorinated Solvents (US EPA, 1998,
EP N600/R-98/128). A brief summary of the biodegradation screening procedure,
including a table summarizing the results, would also be beneficial as there currently no
supporting documentation for the information presented as Figure 7.
Section 4.0 Closing Comments
2. Per the Revised Monitored Natural Attenuation Demonstration Project Data Report for
Quarterly Sampling Event #1 (2nd Quarter 2004), please revise the fifth sentence of the
first paragraph of Section 4.0 to define the US EPA MNA guidance document as
Technical Protocol for Evaluating Natural Attenuation of Chlorinated Solvents (US EPA,
1998, EPN600/R-98/128).
• &iih •
NCDENR
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director Division of Waste Management
Mr. Ken Lucas
Remedial Project Manager
Superfund Branch
· Waste Management Division
US EPA Region IV
61 Forsyth Street, 11th Floor
Atlanta, Georgia 30303
March 30, 2005
RE: Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #3 ( 4th Quarter 2004)
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
· The Superfund Section of the North Carolina Department of Environment and Natural Resources
(NC DENR) has received and reviewed the Monitored Natural Attenuation Demonstration
Project Data Report for Quarterly Sampling Event #3 (4th Quarter 2004) for the Celanese
Corporation National Priorities List (NPL) Site. The Superfund Section offers the following
attached comments. · · ·
The Superfund Section of the NC DENR appreciates the opportunity to comment on this
document. If you have any questions or comments, please feel free to contact me at (919) 733-
2801, extension 349.
Attachment
. Sincerely, ·
<JJ~z~
David B. Mattison
Environmental Engineer
NC Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone [phone] \ FAX [phone] \ Internet http//wastenotnc.org
An Equal Opportunity/ Affinnative Action Employer-Printed on Dual Purpose Recycled Paper
..
Mr. Ken Lucas
March 30, 2005
Page I
•
Monitored Natural Attenuation Demonstration Project Data Report
For Quarterly Sampling Event #3 (4th Quarter 2004)
Celanese Corporation NPL Site
Section 3.2.2 Discussion of Analytical Findings
1. Per .the Revised Monitored Natural Attenuation Demonstration Project Data Report for
Quarterly Sampling Event #1 (2nd Quarter 2004), please revise the third sentence of the
fourth paragraph of Section 3.2.2 to define the United States Environmental Protection
Agency (US EPA) monitored natural attenuation (MNA) guidance document as Technical
Protocol for Evaluating Natural Attenuation of Chlorinated Solvents (US EPA, 1998,
EP A/600/R-98/128). A brief summary of the biodegradation screening procedure,
including a table summarizing the results, would also be beneficial as there currently no
supporting documentation for the information presented as Figure 8.
2. Please revise the last sentence of the fourth paragraph of Section 3.2.2 to correctly
reference Figure 9.
Section 4.0 Closing Comments
3. Per the Revised Monitored Natural Attenuation Demonstration Project Data Report for
Quarterly Sampling Event #1 (2nd Quarter 2004), please revise the fifth sentence of the
first paragraph of Section 4.0 to define the US EPA MNA guidance document as
Technical Protocol for Evaluating Natural Attenuation of Chlorinated Solvents (US EPA,
1998, EP A/600/R-98/128).
Figure 7 Inferred Methane Distribution -November 9-10, 2004
4. In accordance with the data provided in Table 1 and Attachment 1, please correct Figure 7
to indicate that the groundwater sample collected from Inner Tier extraction well IT-4
contained 8.5 J milligrams per liter (mg/L) methane.
• • ® EarthTech
A tqca International Ltd. Company
March 23, 2006
i\1r. Kcnm:th Lucas
Remedial Project Manager
U.S. Ennronmcntal Protection Agency
61 Forsyth St. SW
1\tl~mta. Georgia 30303
Subject: Cebncsc Fibers Operations Site -Shcluy, North Carolma
Monitored Natural Attenuation Demonstration Project
Data Report fur Quarterly Sampling Ewnt #7 (Q4 2005)
Earth Tech Project No. 79750
Document Control Number: 026S8-209
1455 Old Alabama Road
Suite 170
Roswell, GA 30076
P 770.990.1400
F 770.649.8721
earthtech.com
On hchalr ofCNA Holdings, Inc., Earth Tech, Inc. is pleased to enclose two copies of the report entitled
"Monitored Natural Attenuation l.lcrnonstration Project -Data RcpLlrt for Quarterly Sampling Event #7
(Q4 2005) -Operable Unit I -· CNA Holdings, Jnc./Ticotrn (F.K.A. Celanese Fibers Operations) -
Shelby, North Carolina" for your review. \Ve have also tr:rnsmittcd two copies of the report to David
1\-L.1ttispn with NCDENR f'or his review.
Pk:ase contc.ict me if'yo:.1 r:c·2d uny udditiona! information or have any questions.
Sinct'rcly,
~{µJ,JJ(JJ. ~~
Everett W. Glover, Jr. P.E.
Project Manager
cc: Mr. Dave Mattison. NCDENR
Mr. Steve Simpson, CNA Holdings, Inc.
Ms. PEM Carter, Ticona Shelby
u~
iang, Ph.D.
Project Engineer
l:\1rn1k\!'rojects\797501/l'!P\1\IN/I reporr.1\05(!.J i\lA'A R('JJOrt\05(,_}./ ,\/NA He111ir1_rnl'cr/eI1er.rloc
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3/23/]()(J(,
• ® EarthTech
A tqca lnternational Ltd. Company
March 23. 2006
i\fr. Kenneth Lucas
Remedial Project Manager
U.S. Environmental Protection Agency
61 Forsyth St. SW
Atlanta, Georgia 30303
•
1455 Old Alabama Road
Suite 170
Roswell, GA 30076
Subject: Celam·se Fibers Opcraiions Site -Shelby, North Carolina
Monitored Natural Attenuation Demonstration ProJecl
Data Report li,r Quarterly Sampling Event #7 (Q4 2005)
Earth Tech Project No. 79750
Document Control Number: 026SB-209
Dear 1\,lr. Lucas:
P770.990.1400
F 770.649.8721
earth tech.com
On bchall'ofCNA Holdings, fnc., Earth Tech, Inc, is pleased to enclose two copies of the report entitled
"Monitored Natural Attenuation Demonstration Project -Data Report for Quarterly Sampling Event #7
(Q4 2005) -Operable Unit I -CNt\ Holdings, fnc./Ticona (F.K.A. Celanese Fibers Operations) -
Shelby: North Carolina•: for your review. \Ve have also transmitted two copies of the report to Duvid
f'vlattison with NCDENR for his review.
Please contact me if you need any additional information or have any questions.
Sincerely.
Earth Tech, Inc,
Everett W. Glover, Jr. P.E.
Project Ivlanagcr
cc: Mr. Dave Mattison, NCDENR
Mr. Steve Simpson, CNA Holdings, Inc.
Ms. PEM Carter, Ticona Shelby
L:l11ork\f)rojet·ts\79750\ll'{/)\,1/Nil 1eporf.\l05(,)./ 1\IN/l lfrpo11105{}.J ,\!NA Rc1!11r/_cm·l'1Ie11cr.doc
Ill.I
J/23/]I)()(,
• @EarthTech
A "tf/CD International Ltd. Company
February 20, 2006
Mr. Kenneth Lucas
Remedial Project Manager
U.S. Environmental Protection Agency
61 Forsyth St. SW
Atlanta, Georgia 30303
• 1455 Old Alabama Road P 770.990.1400
Suite 170 F 770.649.8721
Roswell, GA 30076 earthtech.com
Subject: Celanese Fibers Operations Site -Shelby, North Carolina
Work Plan for DPT/Monitoring Well Installation
and Quarterly Groundwater Sampling
Earth Tech Project No. 79750
Document Control Number: 026SB-205
Dear Mr. Lucas:
Enclosed are two copies of the document titled "Work Plan for DPT/Monitoring Well Installation and
Quarterly Groundwater Sampling -CNA Holdings, lnc./Ticona (F. K.A. Celanese Fibers
Operations) -Shelby, North Carolina" for your review. This document is being submitted by Earth
Tech on behalf of CNA Holdings, Inc. The work plan presents the basic procedures that will be
used for collection of data to address questions on recent detections of ethylene glycol in the
vicinity of and down gradient from wells F-55 and K-28 as requested in earlier Agency comments
to quarterly Monitored Natural Attenuation Data Reports. Specific responses to the comments are
addressed in the upcoming Monitored Natural Attenuation Data Report on the seventh quarter of
data collection. In addition to addressing the drilling procedures, the work plan addresses the
procedures for collection of future groundwater samples. The next round of groundwater sampling
is scheduled for the week of March 6, 2006.
Please contact us if you need additional information or have questions related to the procedures.
Sincerely,
Earth Tech, Inc.
,-: / ../ /1/
It.!~ / / ·-z; __ (J-c_tt_{:/[V, f:Jeu0 , ~
Everett W. Glover, ~r. P.E.
Project Manager
-'t ~.-Y#c __ v'.
Fi'.,-1' ;_ _.,. .• 1/ y:,--~
Bryon Dahlgren, P E.
Project Engineer
cc: Mr. Dave Mattison, NCDENR (2 copies)
Mr. Steve Simpson, CNA Holdings, Inc.
Ms. PEM Carter, Ticona Shelby
L:\work\Projects\79750\WordProc\2006 Work Pfan\WP DPT MW coverfetter.doc
ms
212012006
• @EarthTech
A tf/CD International Ltd. ComDany
•
1455 Old Alabama Road
Suite 170
Roswell, GA 30076
P 770.990.1400
F 770.649.8721
earthtech.com
January 24, 2006
Mr. Kenneth Lucas
Remedial Project Manager
U.S. Environmental Protection Agency
61 Forsyth St. SW
~r~N: ~~6 rn,~
SUPERFUND SECTION
Atlanta, Georgia 30303
Subject: Celanese Fiber Operations Site -Shelby, North Carolina
Receipt of Comments on Sampling Event #6 Monitored Natural Attenuation
Demonstration Project Data Report
Earth Tech Project No. 79750
Document Control Number: 026S13-204
Dear Mr. Lucas:
This letter is prepared to inform you that Earth Tech Inc. (Earth Tech) has received the
United States Environmental Protection Agency (EPA) comments, dated .January 17, 2006,
on Monitored Natural Attenuation (MNA) Demonstration Project Data Report for Quarterly
Sampling Event #6 (3'' Quarter 2005) for the subject site. Earth Tech has also reviewed the
comments and will address the comments in next MNA Demonstration Project Data Report
(Quarterly Sampling Report #7) which will be submitted in Febniary 2006.
Should you have any question or need any additional information, please feel free to contact
Everett Glover at (770) 990-14 IO or Dora Chiang at (770) 990-14 I 8.
Sincerely.
Earth Tech, Inc.
'--" .
(pr:_ i:,:.;,_,jf(lrD
Everett W. Glover, Jr. P.E.
Project Manager
cc: ',Dave Mattison, NCDENR
Steve Simpson, CNA Holdings, Inc.
PEM Carter. Ticona Shelby
·'.
L: \ 11 ·ork \ ~'roj cl.'/s \ 7975011 I'/ P'1correspo nd cnrc \
Dr"fi EPA response to Gm1111111r?11ts_m1111#6.doc
Project Engineer
0//14/06
• • UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
ATLANTA FEDERAL CENTER
61 FORSYTH STREET
ATLANTA, GEORGIA 30303-8960
JAN 1 7 2()d6
VIA CERTIFIED MAIL
RETURN RECEIPT REQUESTED
4WD SRSEB
Mr. Steve Simpson
Authorized Agent
Clo Celanese Corporation
2525 Blacksburg Road
Grover, North Carolina 28073
~~~;;;,~-~]~
SUPERFIJi~D SECTION
Subject: Monitored Natural Attenuation Demonstration Project Qata Report
Quarterly Sampling Event #6 (3"1 Quarter 2005)
Celanese Corporation NPL Site
Shelby, Cleveland County. NC
Dear Mr. Simpson:
The United States Environment,il Protection Agency (EPA) has reviewed Earth Tech's,
Monitored Natural Attenuation Demonstration Project Data Report Quarterly Sampling Event #6
(3'd Quarter 2005), Celanese Corpori11ion NPL Site. EPA's comments are provided below.
Please address these comments in your submission of the next report.
GENERAL COMMENTS
Rate of Plume Degradation versus the Rate of Plume Redistribution:
A major issue n!garding the ethylene glycol plume in the vicinity of the Inner Tier wells
concerns the rate of degradation versus the rate of plume redistribution since the Inner Tier wells
were shut off. The h~y questions are as follows:
I. Will the plume stabilize within the area of the Outer Tier wells?
2. Will the plume stabilize near the Inner Tier wells?
3. Will it be necessary to start pumping again'1
4. ls the existing monitoring well network adequate for answering these questions?
Internet Address (URL)• http://www.epa.gov
Recycled/Recyclable. Printed w~h Vegetable Oil Based Inks on Recycled Paper (Minimum 30% Postconsumer)
• •
The report states (page I) that the MNA Quarterly Sampling Report #7 will solidly
support the adequacy of MNA and support the request for an extension for the pumping well
shut-down period. The first paragraph of Section 5 (page 9) cites examples of biological activity
as evidence that natural attenuation is working, but biological activity is only one of three lines
of evidence described in the EPA guidelines for evaluating MNA. The other two are
contaminant degradation with distance from a source and contaminant degradation with time,
both measured in monitoring wells along known, well defined flow paths. The text in the second
paragraph on page 9 might be interpreted to indicate that down gradient monitoring wells are not
necessary because there is" ... evidence of biological activity and slow groundwater movement
.... ", but there are few monitoring wells between the Inner and Outer Tiers of pumped wells
which can be used to confirm these interpretations.
EPA guidelines for MNA strongly emphasize that decisions regarding the effectiveness
· ofMNA must be based on field observations, not just on modeling results or calculations. Much
data has been acquired from the existing monitoring well network, but that network was
designed for hydraulic containment by pumping, not for a plume moving under natural hydraulic
gradients. An evaluation ofMNA requires careful examination of groundwater flow directions,
and assurance that the monitoring well network adequately monitors the plume under the non-
pumping conditions.
MNA Quarterly Sampling Report #7 must include carefully constructed water level
contour maps, an evaluation of the existing monitoring network, lmd a proposal to cover any
gaps in the monitoring well network revealed by this evaluation. Monitoring wells must be
located in flow paths between source areas and discharge areas.
Water Level Contour Maps and Surface Water Streams:
The relationships between the surface water streams which bound the site, and the water
levels measured in the monitoring wells shown in Figures 3-1 and 3,2 should be re-evaluated.
Both of these figures show water level contours which pass through the surface water streams as
if the streams don't exist or are perched above the water table. In other words, the maps do not
show groundwater discharging to surface water, but instead show groundwater passing beneath
the streams to discharge elsewhere. This is particularly evident east of wells II-40 and JJ-40, on
the down gradient side (east side) of Figure 3.1, which shows the 710 and 720 foot contours are
unaffected by the stream on the north side of the site.
_If the streams are not flowing anywhere in the area shown on these figures, the contours
are correct as shown because there is no interaction between groundwater and surface water. If
the streams are flowing, the contours are not correct, particularly in the shallow aquifer near the
streams (Figure 3.1). The hydrologist drawing these water level contour maps should determine
the elevation of the stream channel bottoms, determine the location in the stream bottom where
groundwater begins flowing into the stream, and consider these elevations in the shallow aquifer
when contouring the groundwater results. Where the streams are natural discharge areas for
groundwater, the water level contours should show groundwater movement to the streams.
2
• •
While the Outer Tier wells are uncontaminated, this issue may not be particularly important.
However, in other areas where contamination is closer to the streams, the relationship between
shallow groundwater and groundwater discharge to the surface water streams may change
groundwater flow directions close to the streams. Also, clear and accurate identification of
natural groundwater discharges io surface water should be a key element in evaluating the
adequacy of the monitoring well network.
Temporary staff gauges may be established at selected points in the streams to help
define relationships betw_een groundwater and surface water. For secure locations within the
property, adequate staff gauges can be constructed using inexpensive, commonly available
materials, such as a metal fence post and 48" Drywall I-Squares. Surface water elevations
calculated from the height of water on the staff gauges can be contoured with water elevations
from shallow wells, leading to a better understanding of where shallow groundwater discharges
to the streams.
Data Quality Assessment:
Please expand the explanation regarding the failure of field samples from IT-6 and IT-SR
to. correlate with historical data. This situation is described in the last paragraph of tp.t:: Data
Quality Assessment, Section 4.1, and p. 4.
Ground Water Quality Trends Shown In Appendix C:
Ethylene glycol concentrations may be increasing in the following monitoring wells:
F55 definite
IT4 possible
IT5 possible
IT6 definite
IT8R possible
IT9 possible
K.28 ·. definite
025 definite
V23 possible
The probable rate of contaminant movement should be calculated. This estimate should confirm
with field observations. Initial confirmation may be made using direct push methods; however,
additional monitoring wells might be necessary for long-term monitoring.
3
• •
SPECIFIC COMMENTS
Table of Contents
I. Please correct the Table of Contents to indicate that the title of Appendix C is
"Concentrations vs. Time Water Quality Plots".
List of Acronyms
2. Please correct the List of Acronyms to indicate that the acronym "CERCLA" represents
"Comprehensive Environmental Response, Compensation and Liability Act".
Section 1.0 Introduction
3. Please correct the second sentence of the fifth paragraph of Section 1.0 to state "It is
expected that the MNA Quarterly Sampling Report #7 for submission in February 2005
will be prepared not only to summarize the data from the seventh quarter of the shut
down period but also to include detailed discussion of the MNA lines of evidence based
on the data accumulated from 7 quarters."
Section 2.0 Work Performed
4. Please correct the last sentence of Section 2.0 to state "A summary of the laboratory
analytical results is provided in Table 2-3."
Section 4.2.3 MNA Parameters
ORPS
5. Please correct the third sentence of this section to state "The ORP decreases as DO is
used for attenuation of biodegradable organic contaminants." .
6. Please correct the last sentence of the second paragraph of this section to state "In
addition, the groundwater sample was collected from well F-55 using a disposable
bailer ... " '
Sulfate
7. Please correct the sixth and seventh sentences of this section to state "Sulfate was not
depleted at wells CC-33 (I 1.8 mg/L) and 0-25 (268 mg/L) containing negative ORP ·
measurements. In fact, sulfate concentrations at well 0-25 have shown a general
increasing trend since Second Quarter 2004."
4
, • ••
If you have any questions, feel free to call me at 404-562-8953.
cc: David B. Mattison, NC DENR
Sincerely . , ;/f~. /\ 1\,\·\\_l\~~ __ .,, .. , ~' ,,, \t
Kenneth A. Lucas
Remedial Project Manager
North Site Management Branch
Everett W. Glover, Jr., PE, Earth Tech, Inc.
Dave Jenkins, SRTSB
.;
5
• • .;;;;;&;;;;;:;;;~;h
NCDENR
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director Division of Waste Management
January 11, 2006
Mr. Ken Lucas
Remedial Project Manager
Superfund Remedial and Site Investigation Branch
Waste Management Division
US EPA Region IV
6 I Forsyth Street, ll th Floor
Atlanta, Georgia 30303
RE: Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #6 (3 rd Quarter 2005)
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
The North Carolina Department of Environment and Natural Resources (NC DENR) Superfund
Section has received the Monitored Natural Attenuation Demonstration Project Data Report for
Quarterly Sampling Event #6 (3rd Quarter 2005) for the Celanese Corporation National Priorities
List (NPL) Site. The NC DENR Superfund Section has reviewed this document and offers the
following attached comments. ·
The NC DENR Superfund Section appreciates the opportunity to comment on this document. If
you have any questions or comments, please feel free to contact me at [phone].
Attachment
Environmental Engineer
NC DENR Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone [phone] I FAX [phone] I Internet http://wastenotnc.org
An Equal Opportunity/ Affinnative Action Employer-Printed on Dual Purpose Recycled Paper
Mr. Ken Lucas
January 11, 2006
Page I
• •
Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #6 (3 rd Quarter 2005)
Celanese Corporation NPL Site
Table of Contents
1. Please correct the Table of Contents to indicate that the title of Appendix C is
"Concentrations vs. Time Water Quality Plots".
List of Acronyms
2. Please correct the List of Acronyms to indicate that the acronym "CERCLA" rep:resents
"Comprehensive Environmental Response, Compensation and Liability Act".
Section 1.0 Introduction
3. Please correct the second sentence of the fifth paragraph of Section 1.0 to state "It is
expected that the MNA Quarterly Sampling Report #7 for submission in February 2005
will be prepared not only to sununarize the data from the seventh quarter of the shut
down period but also to include detailed discussion of the MNA lines of evidenc,: based
on the data accumulated fro 7 quarters."
Section 2.0 Work Performed
4. Please correct the last sentence of Section 2.0 to state "A summary of the laboratory
analytical results is provided in Table 2-3."
Section 4.2.3 MNA Parameters
ORP
5. Please correct the third sentence of this section to state "The ORP decreases as DO is
used for attenuation of biodegradable organic contaminants."
6. Please correct the last sentence of the second paragraph of this section to state "In
addition, the groundwater sample was collected from well F-55 using a disposable
bailer. .. "
·I
Mr. Ken Lucas
January 11, 2006
Page2
Sulfate
• •
7. Please correct the sixth and seventh sentences of this section to state "Sulfate was not
depleted at wells CC-33 (11.8 mg/L) and 0-25 (268 mg/L) containing negative ORP
measurements. In fact, sulfate concentrations at well 0-25 have shown a general
increasing trend since Second Quarter 2004."
• • @EarthTech
A tqca International Ltd. Company
December 22, 2005
Mr. Kenneth Lucas
Remedial Project Manager
U.S. Environmental Protection Agency
61 Forsyth St. SW
Atlanta, Georgia 30303
Subject:
Dear Mr. Lucas:
Celanese Fibers Operations Site -Shelby, North Carolina
Monitored Natural Attenuation Demonstration Project
Data Report for Quarterly Sampling Event #6 (QJ 2005)
Earth Tech Project No. 79750
Document Control Number: 026SB-202
1455 Old Alabama Road P 770.990.1400
Suite 170 F 770.649.8721
Roswell, GA 30076 earthtech.com
On behalf of CNA Holdings, Inc., Earth Tech, Inc. is pleased to enclose two copies of the report entitled
"Monitored Natural Attenuation Demonstration Project -Data Report for Quarterly Sampling Event #6
(Q3 2005) -Operable Unit I -CNA Holdings, lnc./Ticona (F.K.A. Celanese Fibers Operations) -
Shelby, North Carolina" for your review. We have also transmitted two copies of the report to David
Mattison with NCDENR for his review.
Please contact me if you need any additional information or have any questions.
Sincerely,
Earth Tech, Inc.
(r iLUJ({/J f~l~.c,_-
Everett W. Glover, Jr. P.E.
Project Manager
cc: Mr. Dave Mattison, NCDENR
Mr. Steve Simpson, CNA Holdings, Inc.
Ms. PEM Carter, Ticona Shelby
l:\work\Projecrs\79750\ll'ordProc\05Q3 M,VA Reporrl05Q3 Mi\'A Reporr __ Co\·erletter.doc
ms
/2/22/2005
• UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
VIA CERTIFIED MAIL
ATLANTA FEDERAL CENTER
61 FORSYTH STREET
ATLANTA, GEORGIA 30303-8960
DEC 1 ti 2005
RETURN RECEIPT REQUESTED
4WDSRSEB
Mr. Steve Simpson
Authorized Agent
c/o Celanese Corporation
2525 Blacksburg Road
Grover, North Carolina 28073
Subject: Celanese Fiber Operations Site--Shclby, North Carolina
Monitored Natural Attenuation Demonstration Project
Dear Mr. Simpson:
The United States Environmental Protection Agency (EPA) has reviewed Earth Tech's,
December 12,.20Q5 respqns.e to.EPA'.,s.~\J!Tlf!l.f11\~,on t_he. rep_o,rt,9f,,~.!)1T1P,)i_11~}:l.x,enJ015 for the
Monitored Natural Attenuation Demonstration Project. EPA finds Earth Tech's proposed
approach for addressing the issues identified as I through 3, and directs you proceed with the
work.
With respect to the upcoming end of the 24 month demonstration shut down period;
during the perio_g that the pump & treat system was in operation, the plume boundaries were well
known. Since the Inner Tier wells have been off for 21 months, and since there are relatively
few wells between the Inner Tier and Outer Tier wells (which were shut down long ago) we can
only know where the plume is when it arrives at the Outer Tier. If natural attenuation is
proceeding very effecti{ely, the plume might never get to the Outer Tier again. Although this
would be good news in the long tenn, in the short tenn, we still don't know where the plume is.
EPA recommends that recent water level contour maps and water quality results be evaluated
and gaps in the monitoring well network resolved with the installation of additional monitoring
wells. This may be efficiently accomplished simultaneously with the direct push investigation
described in Earth Tech approach Lo dealing with issue, #1, the ethylene glycol in well F55 .
.. ·; · 1ntemetAddress(URL)·• http://www.epa.gov _,. . .:-;1_, ,: • .·•.-.!(·
•Recycled/Recyclable• Printed wilh Vegetable Oil Based Inks on Recyc_led Paper (Minitrlum 30% ·Poslc0nsumer)
• •
If you have any questions, feel free to call me at 404-562-8953.
cc: David B. Mattison, NC DENR
Sincerely
~~
Kenneth A. Lucas
Remedial Project Manager
North Site Management Branch
Everett W. Glover, Jr., PE, Earth Tech, Inc.
Dave Jenkins, SRTSB
2
@EarthTech
A 1:qca International ltd. Company
December 12, 2005
• •
1455 Old Alabama Road
Suite 170
Roswell, GA 30076
P 770,990.1400
F 770.649.872]
earthtech.com
Mr. Kenneth Lucas
Remedial Project Manager
U.S. Environmental Protection Agency
GI Forsyth St. SW
Atlanta, Georgia 30303
f /B) & @ & ll W &JFi)
II111 DEC 1 4 200S ~j
SUPERFUIVD SECT/ON Subject:
Dear Mr. Lucas:
Celanese Fiher Operations Site -Shelby, North Carolina
Response to Comments on Sampling Event #5 Monitored Natural
Attenuation Demonstration Project Data Report
Earth Tech Project No. 7974 7
Document Control Number: 026S13-200
This purpose of this letter is to respond to EPA's letter providing comments on the 5th
Monitored Natural Attenuation (MNA) Repon. We agree with the comments as presented
and propiisc a strategy to respond to them below.
Issue 1: Ethylene Glycol in Well FSS
It is not clear if the ethylene glycol concentrations at F-55 are the result a new release or
migration of an existing plume. Current site conditions and operations appear to indicate that
any significant release of ethylene glycol within the past several years is unlikely. In either
case, we agree that a more detailed investigation is appropriate to determine more
information regarding the extent of the plume and appropriate response at this location.
We are developing a plan for the completion of a direct push investigation in the vicinity of
F-55. The results of this investigation will be used to establish locations for either one or two
sentinel wells located downgradicnt of F-55. We arc preparing a work plan for the
completion of the direct push study and well installation. We will provide this work plan to
you in early 2006. We will proceed with the work upon approval. Our current schedule
anticipates that the direct push study should proceed in early spring of2006 and well
installation should proceed in early to mid summer.
Issue 2: Need for Background Wells
We agree that an alternate background well should be identified for the site. We recommend
monitoring well C-49. Monitoring well C-49 is upgradicnt of the site and has been used as a
background well in the past. The location of well C-49 is included in the attached figure.
/,:\11·ork\/1rt?fcc1s\79750\IVll'\Draji EPA re.,p1m.1·c r2.doc
sr
12/12/05
• ® EarthTech
A 'tqco International Ltd. Company
Issue 3: ,v!apping of Physical Parameters
• Mr. Kenneth Lucas
U.S. Environmental Protection Agency
December 12, 2005
Page 2
\Ve agree with EPA:s recommen<lation regarding the future presentation of data. A map
detailing the infe1Tcd distribution of Total Organic Carbon will be presented in future reports.
Figures showing the spatial distribution ofORP, conductance and pH will also be presented.
Other spatial distribution figures for additional parameters may also be provided as
appropriate. We will also continue lo present time vs. eonccntrat1on plots for various
parameters and locations to establish the degree of attenuation occurring.
The current 24 month demonstration shut down period will end on March I st, 2006.
Quarterly reports have been submitted on the first five quarters of the 2 years. The sixth
quai1erly report will be submitted in December 2005. After the completion of the sixth report
we will prepare a more detailed report for submission in February 2006. This report will
include data from the seventh quarter of the shut down period. Based on the data we have to
date we arc confident that we will be able to provide a positive indication of MNA
effectiveness at the site. In accordance with this expectation we intend to include in the
report a request that an extension of the shut down period be provided. We are optimistic that
further data collected through the end of the 24 month period will further support this
conclusion. We will collect all data throughout the 2 year period and provide a final
recommendation report by July 2006. Independent investigation and development of
appropriate response at F-55 will continue during this period.
Please contact me if you need any additional information.
Sincerely,
Earth Tech, Inc.
D~~~u-./40w
Everett W. Glover, Jr. P.E.
Project Manager
cc: Dave Mattison, NCDENR
Steve Simpson, CNA 1-!oldings, Inc.
PEM Carter, Ticona Shelby
L:l11·orkll'rojcc1s\79750\IV!Pi/Jraft EPA rr.1po11se r2.doc
ff
ryon
Project Engineer
! 2/12/05
\
J
D-27/D-35/D
I
i
i i
PROPOSED BACKGROUND WELL
A-39
0
•
RECREATION POND
/ _.. -·· -·
/ /
/
/ / /
\
\
\
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SW-3
JJ-40/JJ-65
~
11-40/11-60 /
® / i
/
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@EarthTech
A Tyco International Ltd. Company
•
Legend
© PROPOSED BACKGROUND WELL
0 MONITOR WELL
G IT WELL
G OTWELL
c¢' PEW WELL
... PIEZOMETER
!SJ SURFACE WATER LOC
C i PROPERTY BOUNDARY L
0 250 500
FIGURE 1
BACKGROUND WELL LOCATION
December 2005
CNA Holdings, lnc.rricoma
Shelby, North Carolina
1,000
Feet
79750
•
4WDSRSEB
Mr. Steve OI p
CNA Holdings, Inc., c/o Celanese
2848 Cherry Road -Suite 100
Rock Hill, SC 29730
•
Subject: Celanese Fiber Operations Site--Shelby, North Carolina -
Dear Mr. Olp:
Monitored Natural Attenuation Demonstration Project Data Report for Quarterly
Sampling Event #5 Celanese Fiber Operations Shelby, North Carolina
Consent Decree, Civil Action No. SH-C
The purpose of this letter is to transmit the United States Environmental Protection
Agency's (EPA's), comments on the latest Monitored Natural Attenuation (MNA) Report. This
report represented the results from the 5th MN A sample event for the Celanese site. EPA is
requesting that you provide a written response to the issues raised in this letter within thirty (30)
days of your receipt of this letter.
ISSUE 1-ETHYLENE GLYCOL IN WELL FSS:
The concentration of ethylene glycol is increasing in F55. The data show that a new
release of contamination has occurred. This release has not been controlled. The source of the
release has not been identified. Figures 5 from the I st and 3rd sampling events show that the
ethylene glycol concentration in F55 has been increasing: ·
1,990 mg/L in May 2004
5,300 mg/Lin November, 2004
5,500 mg/Lin February 2005
5,780 mg/Lin May 2005.
This contamination does not appear to be part of the original plume captured by the
recovery well system. These data indicate that there is another contaminant plume in the aquifer
up gradient from the existing remedial measure and is moving toward the area which has already
been cleaned by 15 years of pumping. Natural attenuation can not be approved as a remedy
when a source remains in place and the plume is spreading. A plan must be submitted to EPA
describing where this plume is, where it is going, how this plume will be monitored, where the
Internet Address (URL)• http://www.epa.gov
Recycled/rlecyclabl(I • Printed with Vegetali!e Oil Has~d h1k.s on Recycled-Paper (Minimum 30% Postconsurnar)
• •
sentinel wells are going to be, and what will be done if the contamination reaches the sentinel.
wells. This investigation should lead to an evaluation of remedial measures or containment
measures suitable and appropriate for management of this plume. An Additional monitoring
well should be installed between F55 and Tl!. Please submit a work plan for this new well as
soon as possible.
ISSUE 2 -NEED FOR BACKGROUND WELLS:
None of the monitoring wells sampled during this event appear to be monitoring
background conditions. Well 129 would appear to be the most likely candidate for a background
well, but this well clearly is down gradient from most of the facility. It has relatively high TOC,
N03 and S04 concentrations relative to some other wells. Analyses from a background well
which indicates what background concentrations are for all the contaminant, contaminant
indicators and MNA parameters would be useful. An appropriate background well should be
identified and proposed to EPA for inclusion in the next sampling event. Please see the next · . .
comments regarding mapping of physical parameters.
ISSUE 3 -MAPPING OF PHYSICAL PARAMETERS:
These sampling event reports present two graphical ways to evaluate conditions in the
residual contaminant plume: maps of contaminant concentrations and graphs of contaminant
concentrations versus time. Reports from previous sample events have included a map-figure
showing Inferred Total Organic Carbon Distribution. This presentation is missing from the most
recent report. As described in the report for the 4th Sampling Event (p.6), this presentation may
present a more reasonable picture of the distribution of ethylene glycol and the residual
contaminant mass. Where possible, the map-view presentations should remain consistent from
report to report, and the TOC map does seem to have been useful and probably should be
· included to the next sampling event report.
Another figure was also discontinued. The figure in earlier reports showing Anaerobic
Biodegradation Screening Parameters was appropriate for a one-time presentation, but
discontinuation of this figure was appropriate in the subsequent reports and need not be included
in the future.
Map-figures showing the results of field chemistry measurem_ents, particularly ORP,
conductance and pH, should be included in the next report. There probably is no point in
presenting dissolved oxygen results because of the general unreliability of the field
measurements. Turbidity and temperature probably will not provide useful information. The
potential value of these presentations should be evaluated. The presentation of any plots of
indicator parameters which appear to be useful as indicators of contaminant migration should be
continued in subsequent reports.
2
• •
The April 2004 Explanation of Significant Differences to the March 28, 1998 OU I
Record of Decision allowed for a 24-month shutdown of the extraction/treatment system. It is
anticipated that after the 24-month shutdown the groundwater pump-and treat system will be
restarted. Any changes proposed to the operation of the system, upon restart, must be approved
by EPA. EPA will take into consideration the results of the MNA evaluation as it considers
proposed modifications to the operation of the system.
cc:
If you have any questions, feel free to call me at 404-562-8953.
David B. Mattison, NC DENR
Sincerely
~~~-lL__
Kenneth A. Lucas
Remedial Project Manager
North Site Management Branch
Jerry Kubal, P.G., Kubal-Furr & Associates
Dave Jenkins, SRTSB
3
• IJ·':?'A -~;-~-~ •
NCDENR
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director Division of Waste Management
August 24, 2005
Mr. Ken Lucas
Remedial Project Manager
Superfund Remedial_ and Site Investigation Branch
Waste Management Division
US EPA Region IV
61 Forsyth Street, 11 th Floor
Atlanta, Georgia 30303
RE: Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #5 (2nd Quarter 2005)
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
The North Carolina Department of Environment and Natural Resources (NC DENR) Superfund
Section has received the Monitored Natural Attenuation Demonstration Project Data Report for
Quarterly Sampling Event #5 (2 nd Quarter 2005) for the Celanese Corporation National Priorities
List (NPL) Site. The NC DENR Superfund Section has reviewed this document and offers the
following attached comments.
The NC DENR Superfund Section appreciates the opportunity to comment on this document. If
you have any questions or comments, please feel free to contact me at [phone].
Attachment
Sincerely,
Damci 8 !Ylo±usoµ) dy
David B. Mattison
Environmental Engineer
NC DENR Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone 919'.508-8400 \ FAX [phone] \ Internet http://wastenotnc.org
An Equal Opportunity/ Affirmative Action Employer-Printed on Dual Purpose Recycled Paper
Mr. Ken Lucas
August 24, 2005
Page 1
• •
Monitored Natural Attenuation Demonstration Project Data Report
For Quarterly Sampling Event #5 (2 nd Quarter 2005)
Celanese Corporation NPL Site
Table of Contents
1. Please revise the Table of Contents to reflect the correct page numbers for Section 2.0,
Section 3.0, Section 3.1, Section 3.2, Section 3.2.1, and Section 3.2.2.
Section 1.0 Introduction
2. Please correct the last sentence of Section 1.0 to state "The current document represents
the fifth data report summarizing the 2nd Quarter 2005 sampling event (i.e., MNA
Quarterly Sampling #5)."
Section 2.0 Work Performed
3. Please correct the fourth sentence of Section 2.0 to state "Analysis of dissolved gase,s
(methane and carbon dioxide) was performed by Microseeps of Pittsburgh, PA under
subcontract to Davis & Floyd."
Section 3.2.1 Data Quality Assessment
4. Please correct the first sentence of Section 3.2.1 to state "Regarding sample collection,
the field sampling logs indicate that 10 of the 21 wells sampled using low flow protocols
were within the sampling guidelines for turbidity of 10 NTUs (nephelometric turbidity
units)."
Section 3.2.2 Discussion of Analytical Findings
5. Please correct the last sentence of the first paragraph of Section 3.2.2 to state "The 2nd
Quarter 2005 MNA data, including the anaerobic biodegradation screening parameters,
are shown on Figures 5-12."
6. Please correct the fourth sentence of the second paragraph of Section 3.2.2 to state,
"Although not directly applicable to ethylene glycol degradation, the screening criteria
were applied to the 2nd Quarter 2005 data set to produce the numerical results (Table 3)
which are shown on Figure 5."
• &i;h
MCDEMR
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director
Mr. Ken Lucas
Remedial Project Manager
Superfund Branch
Waste Management Division
US EPA Region IV
61 Forsyth Street, 11th Floor
Atlanta, Georgia 30303
Division of Waste Management
July 27, 2005
RE: Monitored Natural Attenuation Demonstration Project Data Report
Quarterly Sampling Event #4 (1 st Quarter 2005)
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
The Superfund Section of the North Carolina Department of Environment and Natural Resources
(NC DENR) has received and reviewed the Monitored Natural Attenuation Demonstration
Project Data Report for Quarterly Sampling Event #4 (1 st Quarter 2005) for the Celanese
Corporation National Priorities List (NPL) Site. The Superfund Section offers the following
attached comments.
The NC DENR Superfund Section appreciates the opportunity to comment on this document. If
you have any questions or comments, please feel free to contact me at [phone].
Attachment
Sincerely,
DCWLd 8 f'fl..a;Cti--sw-j d y
David B. Mattison
Environmental Engineer
NC DENR Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone [phone] I FAX [phone] I Internet http://wastenotnc.org
An Equal Opportunity / Affirmative Action Employer-Printed on Dual Purpose Recycled Paper
Mr. Ken Lucas
July 27, 2005
Page I
• •
Monitored Natural Attenuation Demonstration Project Data Report
For Quarterly Sampling Event #4 (1st Quarter 2005)
Celanese Corporation NPL Site
Table of Contents
I. Please revise the Table of Contents to reflect the correct page numbers for Section 2.0,
Section 3.0, Section 3.1, Section 3.2, Section 3.2.1, and Section 3.2.2.
Section 3.2.2 Discussion of Analytical Findings
2. Please correct the fourth sentence of the second paragraph of Section 3.2.2 to state,
"Although not directly applicable to ethylene glycol degradation, the screening criteria
were applied to the I st Quarter 2005 data set to produce the numerical results (Table 3)
which are shown on Figure 5."
3. Please expound upon the relationship between the ethylene glycol concentrations and
total organic carbon (TOC) concentrations expressed in the sixth paragraph of Section
3.2.2. Although the relationship appears clearly at monitoring wells F-55, IT-SR, K-28,
and V-23, please address whether the elevated TOC concentrations observed at
monitoring wells IT-5, IT-6, IT-7, IT-9, and 0-25 are cause for alarm, are indicative of
ethylene glycol contamination or degradation, or are attributable to some other native or
man-made source.
Table 2 Water Quality Data (Field Parameters)
4. Please revise Table 2 to include all of the turbidity measurements collected during
Monitored Natural Attenuation (MNA) Quarterly Sampling Event #4 (I st Quarter 2005).
Post Office Box 2732 I 0
Tampa, FL 33688-32 I 0
813-265-2338
FAX-265-3649
Mr. Kenneth A. Lucas
U.S. EPA Region IV
Atlanta Federal Center
6 I Forsyth Street
Atlanta, GA 30303-8960
• Kubal-Furr & Associates.
Environmental Management Services
May 12, 2005
Post Office Box 80247
Simpsonville, SC 29680-0247
864-962-9490
FAX-962-5309
fB)~@lgO\YJ~fm
U71 MAY 1 6 7005 ~
SUPERFUND SECTIOI~
Re: Letter of April 11, 2005 to Steve Olp-Comments on Q4 2004 MNA Report
Dear Ken:
On behalf of Celanese, I have been asked to respond to comments received from the EPA on the Q4 2004
monitored natural attenuation (MNA) report prepared by Kubal-Furr & Associates. We've provided item-by-item
responses to the specific comments in your letter and wanted to briefly respond to the broad questions posed in
your prefatory comments.
In your letter you point out the need to address two primary concerns in future reports: (I) ls the plume
expanding now that hydraulic containment has been removed? and, (2) ls MNA working sufficiently to contain
the plume within the area currently contaminated? The short answer to both these questions is yes. There is some
indication that with cessation of pumping, the "plume" has migrated to nearby downgradient monitor well K-28,
but this migration was not unexpected and has occurred in response to the flow system equilibrating to the
current, non-pumping conditions. However, while the plume may have expanded slightly, the data collected
during the MNA demonstration project indicate that the plume is still confined primarily to the former source area
and has not migrated off into new or unexpected areas. In accordance with your comments, we will al:tempt to
better portray these findings in future reports.
Response to Specific Comments
1. Groundwater Contamination & Free Product at F-55.
Water levels and product thickness is measured at well F-55 and these data are provided in each semiannual
report. This information is collected with an interface probe rather than with the water-level indicator and
typically is collected during a quarterly sampling event but not necessarily at the same time as the sitewide water
levels. That's why the water-level data may not be posted for F-55 on the potentiometric surface maps because it
was not collected on the date the map was prepared. We can add it in the future and just footnote that it was
collected on a different date.
Regarding free product at F-55, there is a quarterly program set up where Kubal-Furr measures product
thickness and bails any product (DowTherm) that accumulates in this well between quarterly events. The
• • Mr. Kenneth A. Lucas - 2 -May 12, 2005
measurements and amount bailed are reported on and presented in the semiannual reports and have been for the
past few years. Accumulations of DowTherm removed from F-55 are containerized and Ticona (PEM Carter)
arranges for proper disposal.
At one time, there was automated recovery of product at F-55 and there were four active recovery wells
(PEW-I thru 4) pumping ground water to contain a suspected DowTherm "spill." Upon review of several years
worth of operating data from this PEW system, it was noted that less than a gallon of product had been recovered
at F-55, one of the extraction wells (PEW-2) was improperly constructed and could allow cross communication
between the shallow saprolite and upper bedrock, and that the recovery wells were placed at the bedrock/saprolite
contact and were actually drawing any contamination down to the top of the bedrock before pumping it back to
the surface. Because this program was done under a work plan approved by the DENR, following the review of
operating data, a petition was made to the State to plug back well PEW-2, discontinue the pumping from the other
PEW wells, and remove the automated recovery system from F-55. The State approved this request which
included routine monitoring of the PEW wells and F-55 and the EPA agreed to allow reporting of these data in the
semiannual CERCLA reports as a separate section rather than have to continue to prepare stand-alone PEW
quarterly reports.
It's Celanese's position that they've been responsive to the F-55 situation and have been dutifully reporting
any product accumulations and removals. If constituents are migrating from this apparently isolated source area,
they are several hundred feet upgradient of the former OU-2 source area where the major occurrences of ethylene
glycol are noted to exist. Should the ethylene glycol from F-55 continue to migrate downgradient, the impacts that
would be expected would be an increase in ethylene glycol concentrations at well Tl-I but an actual improvement
in water quality conditions at well Y-23. Before a full-blown investigation of this area is undertaken, several
existing wells around and downgradient of F-55 could be tested for ethylene glycol, TOC and selected MNA
parameters to see if there is any indication of a wider-spread ethylene glycol plume. At that point, a decision
could be made as to the need for additional work or a more in depth investigation.
2. Increasing Ethylene Glycol Contamination at Monitoring Well K-28
Constituents have been reported as present in the past at K-28 (e.g., benzene) prior to initiating ground-
water extraction at the former source area and these data have been presented in each semiannual report. While
there are long-term data for K-28 for volatiles and TOC, we cannot provide you with 'Similar data for other
constituents such as ethylene glycol. Ethylene glycol was not routinely analyzed during the CERCLA
monitoring with the exception of combined influent and effluent samples from the Inner Tier extraction wells.
Therefore, there is limited ethylene glycol data at individual wells except for what has been collected during the
MNA demonstration project.
We agree that continued increases in the concentration of ethylene glycol at K-28 and occurrences at
downgradient well N-29 should be evaluated during subsequent monitoring to determine whether other actions
are appropriate. We expect to address plume migration in a ground-water flow and contaminant transport model
that is planned to be developed in early 2006.
3. Well Screen Lengths, Groundwater Flow Directions and Demonstration of MNA:
We completely understand the EPA's discussion of screen lengths and the associated problems determining
accurately both potentiometric surface maps and also degradation versus distance demonstrations of natural
attenuation. As requested, we will begin preparing time versus concentration (degradation versus time) plots at
individual wells in an attempt to better assess natural attenuation trends.·
Kubal-Furr & Associates
.:;,. • • Mr. Kenneth A. Lucas - 3 -May 12, 2005
4. Turbidity and Total Organic Carbon
We understand the EPA's concerns about potential interferences in the total organic carbon (TOC) values as
they relate to ethylene glycol concentrations. We will prepare plots of TOC concentration versus ethylene glycol
for the next quarterly report in order to establish whether a statistical correlation exists between these constituents ..
5. Detection Limits Used in Analyses
The estimated flags have been placed on the methane data because they were analyzed outside the holding
time of 14 days for volatiles in water as described in the National Functional Guidelines (NFGs). The laboratory,
Microseeps does not have an established hold time in its SOPs for gases analyzed by their proprietary method
AMX20GAx but internal studies have shown no degradation of constituents analyzed in up to 30 days.
Unfortunately, these internal studies have not been independently verified and accepted by the EPA and DENR
and Kubal-Furr defaulted to the NFGs 14 day hold time in this case. Because the samples were analyzed outside
14 days, they received an estimated "J" flag. Therefore, there is not a problem with the detection levels, rather it's
been a problem with the laboratory (Microseeps) analyzing the samples in a timely manner. Microseeps has
agreed to analyze all subsequent samples within 14 days. If you will refer to the Q4 2004 MNA report text in
Section 3.2.1 Data Quality Assessment, there is detailed presentation concerning the gases data.
6. Section 3.2.2 Discussion of Analytical Findings
Future MNA reports will provide the specific reference citation in the text as requested. Also, the requested
summary of the screening method and table showing the data will be included in the next data report. A copy of
the revised page, including the correct reference to Figure 9 is enclosed.
7. Section 4.0 Closing Comments
Future MNA reports will provide the specific reference citation in the text as requested. The revised page
citing the full reference is attached.
8. Figure 7. Inferred Methane Distribution-November 9-10, 2004
This figure has been corrected to show the correct value at IT-4 of 8.51 mg/Land is attached
Ken, I believe this covers all the items addressed in your letter. Please give me a call after you've had a
chance to review this information if you have any questions or want to discuss these items further.
Sincerely,
,/z{L~
Jerry E. Kubal, P.G.
Presid6nt
cc: .IDave Mattison, DENR (w/Attachments)
Rick Ramirez, Steve Olp, Celanese (w/Attachments)
Dan Flynn, Esq., Rich Hanlon, Celanese (w/o Attachments)
PEM Carter, Ticona (w/Attachments)
Everett Glover, EarthTech (w/o Attachments)
Kubal-Furr & Associates
4WDSRSEB
Mr. Steve Olp
• •
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
flEGION 4
AlLAl,JrA cEDERAL CENlTH
,; 1 FOf1:3YTH STREET
ATLANTA, GEORGIA 30308-8%0
APR 1 1 2005
CNA Holdings, Inc., c/o Celanese
2848 Cherry Road -Suite _1 00
Rock Hill, SC 29730
Subject: 4th Quarter 2004, Report -Monitored Natural Attenuation Project.
Celanese Corporation Shelby Fiber Site, Shelby, North Carolina
Consent Decree, Civil Action No. SH-C-88-212
Dear Mr. Olp:
The purpose of this letter is to transmit the U.S. Environmental Protection Agency's
(EPA's) comments on the 4th Quarter 2004 Monitored Natural Attenuation (MNA) report. There
are two primary concerns which must be addressed in future reports:
1. Is the plume expanding now that hydraulic containment has been removed?
2. Is MNA working sufficiently to contain the plume within the area currently
contaminated?
At this time there is no clear indication that the old plume is moving, however, a new
plume at F55 may be moving. In order to get a clear picture of the potential for success of MNA,
analysis of ethylene glycol concentration trends versus time must be included in the next sample
· results report and up-dated in all subsequent reports. This analysis should demonstrate the
unique history of contamination at this-site, including concentrations from the time
contamination was discovered, results during the 15 years of pump & treat operations, plus post-
pumping and MNA sampling results. Previous reports for this site have shown that the pump &
treat remedial measure successfully limited the extent of groundwater contamination. Analysis
of the MNA sample data must insure that this progress will not be lost. Expansion of the plume
following the cessation of pumping must be documented to show that plume is behaving as
expected.
The closing comments of the report (Section 4 p.8) state that the data set from the 3''
MNA sample event provides strong evidence that natural attenuation is working to degrade
ethylene glycol. However, relatively little of this data is presented in a form which makes this
case. The maps showing the distribution of contaminants (Figures 6-12) do not make the case.
1!1t&mat Addr&es (URL)• h!tµ://www.epa.gov
Hu::yct0,t,,Tioc)''Cl.ibh1 •P•inhid with V!lgelabl<: Oil DaSud l11ks on Recycled Paper (Minimum 30% Poslconsurner)
•
Presentations purporting showing degradation with distance from the source arc easily
challenged due to well construction issues. Figures showing degradation versus time would
better make the case.
Analyses presented in the report of the natural attenuation indicator parameters and field
chemistry results is limited mostly to text descriptions rather than graphical comparisons. As
stated above, there is no clear indication that the plumes are not attenuating. Similarly, there is
no undeniable indication that natural attenuation is really working. Three MNA sampling events
have occurred. Years of earlier data are available. The available data must be used to
demonstrate contaminant trends versus time. This analysis should be arranged so that various
chemical data can be plotted together to make a conclusive presentation that the data collected do
show that natural attenuation is working.
Additional concerns which must be addressed are described in the enclosure to this letter.
Please provide a written response to each of these concerns within 30-days of your receipt of this
letter. Your response should indicate your position with respect to EPA's comments. Your
response should also detail your intentions address the issues that have been identified by EPA.
If you have any questions, please call me at 404-562-8953.
Enclosure
cc: David B. Mattison, NC DENR
Kenneth A. Lucas
Remedial Project Manager
Superfund Remedial and Site Evaluation Branch
Jerry Kubal, P.G.,, Kubal-Furr & Associates
Dave Jenkins, SRTSB
',
2
•
Enclosure Additional Comments
4th Quarter.2004, Report -Monitored Natural Attenuation Project.
;J/ ' 1. Groundwater Contamination & Free Product at FSS
The well purging record in the appendix shows a depth to water measurement for this well as
37.40 feet on 11/10/04. The text on page 2 states that water levels were not collected at
monitoring well F55 because of the accumulation of free DowTherm which cause problems in
decontaminating the water level probe. So the statement on page 2 is confusing. Water level
measurements and free product thickness measurements from this well are critical in evaluating
status of this contamination.
Comparison of Figures 5 show that the ethylene glycol concentrations in F55 increased from
1,990 mg/Lin May 2004 to 5,300 mg/Lin November, 2004. The nearest monitoring well down
gradient from F55 appears to be Tl I, which is almost 400 feet away, so the lateral and vertical
extent of contamination at.F55 is unknown. The text on page 5 states that the contamination at
F55 " ... is interpreted as a-small, isolated source not related to the former OU2 source area at V-
23 and the Inner Tier" of pumped wells.
A work plan is needed to determine the lateral and vertical extent of contamination at F55. The
plume appears destined to impact an area that was cleaned up by the extraction and treatment
system. The work plan should include direct push samples and new monitoring wells in the
vicinity of F55.
2. Increasing Ethylene Glycol Contamination at Monitoring Well K28
Comparison of Figures 5 show that the ethylene glycol concentrations in K28 increased from <35
mg/Lin May 2004 to 227 ing/L in November, 2004. The nearest monitoring well down gradient
from K28 appears to be N29, which is almost 200 feet away. If the ethylene glycol concentration
in N29 begins to rise in the next sample events, or if concentrations continue to increase at K28,
the expanding plume may need to be actively addressed.
3. Well Screen Lengths, Groundwater Flow Directions and Demonstration of MNA:
As noted on page 3, the water level contour maps give " ... a somewhat-generalized picture of
ground-water movement .. :" at this site. This is because many of the wells in the central portion
of the site were designed as production wells for the pump & treat system. By design, the
screens in these wells are relatively long, therefore water level measurements and water quality
sample results arc not necessarily representative of conditions in the plume, but measurements of
average coriditions integrated over the length of the screen. Jn other words, vertical hydraulic
gradients are wiped out in the well and water quality samples may include water from
contaminated and uncontaminated portions of the aquifer. The proportions of contaminated and
Enclosure MNA 4th Qtr Rpt Comments-Page I of 4
• •
uncontaminated water in each well can't be determined, but it probably does vary from well to
well.
There are two primary methods for plotting the trend of natural attenuation at a site. One method
is a projection of degradation in contaminant mass as distance from the source increases. The
first method (degradation vs distance)-assumes that a decrease in contaminant mass between
points A & B is due to natural attenuation. One underlying assumption is that water from point
A actually flows to point B, if it does not, then the comparison is not valid. Another assumption
is that samples at points A & B actually measure the same dimensions of the plume. If the up
gradient well samples the most contaminated part of the plume, while the down gradient well
samples only the uppermost fringe because the bulk of the plume sank below the well screen by
the time it got to point B, then the apparent degradation between A & B may be greatly over
estimated. Because the water level contour maps are only "generalized pictures" (page 3) of
groundwater flow directions at this site, and because vertical hydraulic gradients can not be
determined across the site, we can never be certain that contaminated water at any point B really
came from a particular pojnt A, so degradation versus distance estimates at this site will always
be questionable. For example, drawing flow paths on Figure 2 suggests that at least 3 different
flow paths may be present-in the set of wells proposed on page 6 as a demonstration of
degradation versus distance. Wells TI! and U38 are on one flow path which probably discharges
toward the stream south of the site. Well K28 is on another flow path which discharges toward
the stream north of the site. Wells 025 and W23 are more toward the center of the groundwater
flow divide where groundwater probably moves more eastward rather than north or south. Since
the flow directions apparent on Figure 2 represent only a generalized picture, the interpretation of
degradation versus distance presented on page 6 can not be accepted with certainty.
The other method for plotting the trend of natural attenuation at a site is degradation versus time.
This second method (degradation vs time) evaluates contaminant concentration trends at selected
individual points over time, rather than between two different points. Therefore, the question of
whether the water sampled is on the same flow path is not relevant. Also, the method assumes
that the portion of the plume thickness sampled from one event to the next remains the same,
which seems like a reason~ble assumption, but one which can not be tested without great
expense.
Determinations of the progress and effectiveness of MNA at this site should rely more heavily on
evaluation of contaminant concentrations versus time, because of the uncertainty built into this
monitoring well network.
Enc,losure MNA 4th Qtr Rpt Comments-Page 2 of 4
" • • . '
4. Turbidity and Total Organic Carbon:
The text on page 5 states that.the" ... distribution of total organic carbon ... (Figure 6) ... appears
to present a more reasonable, although indirect, picture of the distribution of ethylene glycol and
the residual contaminant mass ... ". But at the same time, the text on page 4 states that the high
turbidity ( <l0NTUs) recorded in many of the samples probably was caused by bio-fouling and
bacterial build-up on the well casings and well screens. The bio-fouling and bacterial build-up,
which may be increasing the TOC results in the samples, might also be due to other natural
attenuation processes, or simply due to changes in chemical conditions in the aquifer related to
the cessation of pumping in March, 2004. It may be useful to plot TOC concentrations versus
time on the same figure with ethylene glycol concentrations to verify a relationship between these
concentrations.
5. Detection Limits Used in Analyses:
Comparison of the methane distributions observed in the 1st (Sept 2004 Figure 6) and 3'" (Feb
2005 Figure 7) sampling events show that many of the methane values reported in Event 3 are
estimated. In many cases, the detection limits are higher than the unqualified values reported in
the same wells from the I" Event. When "J" values are higher than previously reported results ' from a well, there is no way to tell what is really happening.
The closing comments of the report for the 3'0 Event (Section 4 page 8) state that the
groundwater contains elevated levels of methane in areas with high ethylene glycol, indicating
and active methanogenic population (lots of bugs eating the contaminants and making methane in
the process). But the elevated methane values on Figure 7 are mostly estimated values with "J"
qualifiers. The detection limits should be lowered if possible.
6. Section 3.2.2 Discussion of Analytical Findings
Please revise the third sentence of the fourth paragraph of Section 3.2.2 to define the United
States Environmental Protection Agency (US EPA) monitored natural attenuation (MNA)
guidance document as Technical Protoi.:olfor Evaluating Natural Attenuation of Chlorinated
Solvents (US EPA, 1998, EPA/600/R-98/128).
Also please add brief summary of the biodegradation screening procedure, including a table
summarizing the results. This would be beneficial, as there currently no supporting
documentation for the information presented as Figure 8.
Lastly, please revise the last sentence of the fourth paragraph of Section 3.2.2 to correctly
reference Figure 9.
Enclosure MNA 4th Qtr Rpt Comments-Page 3 of 4
• • .. ,J,, • .. ,:
7. Section 4.0 Closing Comments
Please revise the fifth sentence of the first paragraph of Section 4.0 to define the US EPA MNA
guidance document as Technical Protocol for Evaluating Natural Attenuation of Chlorinated
Solvents (US EPA, 1998, EPN600/R-98/128).
8. Figure 7 Inferred Methane Distribution • November 9-10, 2004
In accordance with the data provided in Table I and Attachment I, please correct Figure 7 to
indicate that the groundwater sample collected from Inner Tier extraction w_ell IT-4 contained 8.5
J milligrams per liter (mg/L) methane.
Enclosure MNA 4th Qtr Rpt Comments-Page 4 of 4
.;;.;;;;&.;;..'~iih
NCDENR
North Carolina Department of Environment and Natural Resources
Dexter R. Matthews, Director
Mr. Ken Lucas
Remedial Project Manager
Superfund Branch
Waste Management Division
. US EPA Region IV
61 Forsyth Street, 11 th Floor
Atlanta, Georgia 30303
Division of Waste Management·
December 14, 2004
RE: Monitored Natural Attenuation Demonstration Project Data Report
2nd Quarter 2004
Celanese Corporation NPL Site
Shelby, Cleveland County, NC
Dear Mr. Lucas:
Michael F. Easley, Governor
William G. Ross Jr., Secretary
The Superfund Section of the North Carolina Department of Environment and Natural Resources
(NC DENR) has received and reviewed the Monitored Natural Attenuation Demonstration
Project Data Report -2nd Quarter 2004 for the Celanese Corporation National Priorities List
(NPL) Site. The Superfund Section offers the following attached comments.
The Superfund Section of the NC DENR appreciates the opportunity to comment on this
document. If you have any questions or comments, please feel free to contact me at (919) 733-
2801, extension 349.
Attachment
Sincerely,
Daw:l 13. ma..tti.sn--ldr
David B. Mattison, CHMM
Environmental Engineer
NC Superfund Section
1646 Mail Service Center, Raleigh, North Carolina 27699-1646
Phone [phone] I FAX [phone] I Internet http://wastenotnc.cirg
An Equal Opportunity/ Affirmative Action Employer-Printed on Dual Purpose Recycled Paper
Mr. Ken Lucas
December 14, 2004
. Page I
• •
MONITORED NATURAL ATTENUATION DEMONSTRATION
PROJECT DATA REPORT -2ND QUARTER 2004.
Celanese Corporation NPL Site
Table of Contents
I. Please correct the Table of Contents to indicate that the title of Figure 7 is "Anaerobic
Biodegradation Screening Parameters -May 24-26, 2004".
Section 3.2 Ground-Water Quality
2. The third sentence of the fifth paragraph of Section 3.2 refers to Figure 7 and monitored
natural attenuation (MNA) screening parameters. Please revise this sentence to define i:he
term "MNA screening parameters".
3. Please revise Section 3.2 to include much greater detail regarding the standards to which
the results of the pilot study are to be evaluated in order to determine the effectiveness of
the pilot study, a description of the methodologies proposed for use with these results for
groundwater fate and transport modeling to ensure the protection of human health and the
environment as well as the timeframe for achieving North Carolina groundwater
standards, an evaluation of the data quality and associated error analysis, etc.
Table 1 Water Quality Data (Laboratory Parameters)
4. Please correct Table 1 to indicate the results for the groundwater sample collected from
monitoring well J-28.
5. Table 1 indicates that the samples collected from groundwater wells F-55 and IT-8R
contained no detectable concentrations of sulfate at a laboratory detection limit of 2.5
milligrams per liter (mg/L). However, the laboratory analytical results included in
Attachment I indicate that the samples collected from groundwater wells F-55 and IT-8R
contained no detectable concentrations of sulfate at a laboratory detection limit of2.S.-
mg/L, but with an "X" qualifier .. Please clarify this discrepancy.
6. Please revise Table I to include the laboratory analytical results of the quality
assurance/quality control (QNQC) samples collected for this sampling event (i.e., field
blank FB-1 and duplicate samples DUP-1 and DUP-2).
Mr. Ken Lucas
December 14, 2004
Page 2
•
Table 2 Water Quality Data (Field Parameters)
•
7. Please correct Table 2 to indicate the results for the groundwater sample collected from·
monitoring well J-28.
8. Please correct Table 2 to indicate that the groundwater sample collected from monitoring
well U-38 during the 2nd Quarter 2004 sampling event contained 7.03-mg/L dissolved
oxygen (DO).
Figure 6 Inferred Methane Distribution
9. Please correct Figure 6 to indicate that the groundwater sample collected from monitoring
well TI-! during the 2nd Quarter 2004 sampling event contained 0.0066-mg/L methan1!.
Figure 8 Inferred Alkalinity (Total) Distribution
I 0. Please correct Figure 8 to indicate that the groundwater sample collected from monitoring
well TI-! during the 2nd Quarter 2004 sampling event contained 17.0-mg/L alkalinity
(total).
11. Please correct Figure 8 to indicate that the groundwater sample collected from monitoring
well CC-33 during the 2nd Quarter 2004 sampling event contained 34.0-mg/L alkalinity
(total).
Attachment 1 MNA Q2 '04 Water Quality Data Report
12. Attachment I includes the laboratory analytical results for the groundwater samples
collected from monitoring wells K-28 and V-23 during the 2nd Quarter 2004 groundwater
sampling event. However, the laboratory analytical results for the total organic carbon·
analyses performed on groundwater samples from monitoring wells K-28 and V-23 were
inadvertently omitted from Attachment I. Please correct this oversight.
• Kubal-Furr & Associates •
------------Environmental Management Services
Post Office Box 273210
Tampa, FL 33688-3210
[phone]
FAX [phone]
Mr. Kenneth Lucas
Remedial Project Manager
U.S. Environmental Protection
Agency, Region IV
61 Forsyth Street
Atlanta, GA 30303
October 18, 2004
Re: Revised 2nd Quarter 2004 MNA Data Report Figures
Dear Mr. Lucas:
Post Office Box 80247
Simpsonville, SC 29680-0247
[phone]
FAX [phone]
rB) rn @ rn □ w &: ~o~-1
iru OCT 2 0 2004 lw
SUPtRFUND SECl!Oi~
As I was preparing figures for the 3rd Quarter 2004 MNA data report, I found an error in
several of the figures from the 2nd Quarter 2004 MNA report sent to you in September. These
have been corrected and are included here as attachments.
The affected figures are 6 through 12. The configuration and inferred distribution of
constituents on these figures was correct but the color-coded legend was in error and has been
changed on the attached replacements. Figures 11 and 12 were correct in the original document
but ended up moving down a shade in the coding in order to make all figures consistent.
I have enclosed three punched sets of replacement figures as you requested. I've also sent
copies to David Mattison with DENR. If you have access to an lbico binder, it will be fairly easy
to pull out the original figures and replace them with these.
Please contact me at 813-265-2338, to discuss any questions you may about the changes
made to these figures.
Sincerely,
Kubal-Furr & Associates
dl/L~
Jer~ J Kubal, P.G.
President
cc: w/Attachments
Mr. David Mattison, NCDENR /
Mr. Steven F. Olp, Celanese Americas
Ms. PEM Carter, Ticona-Shelby ESHA
Mr. Everett Glover, Earth-Tech