| |
 
December 19, 2005
Paul D. McKechnie, Director Public Liaison/Acting Ombudsman
U.S. EPA, Office of Inspector General
Office of Congressional and Public Liaison
Boston Sub Office
1 Congress Street, Suite 110
Boston, Massachusetts 02114-2023
Re: Comment from the Glynn Environmental Coalition on the Office of
Inspector General Ombudsman Report, Appropriate Testing and Timely Reporting
Are Needed at the Hercules 009 Landfill Superfund Site, Brunswick, Georgia,
Report 2005-P-00022, September 26, 2005.
Mr. McKechnie,
The Glynn Environmental Coalition (GEC) is submitting the following comments
on the Office of Inspector General’s (OIG) Report, Appropriate Testing and
Timely Reporting Are Needed at the Hercules 009 Landfill Superfund Site,
Brunswick, Georgia, Report 2005-P-00022, September 26, 2005 (Report). We
trust the Report will be improved as comments solicited from EPA Region 4
and other parties are considered by the OIG. We understand that the opinion
and findings of the OIG as stated in the Report do not necessarily represent
the final EPA OIG position. We trust the OIG will take the following
comments into consideration in formulating the final OIG position.
Sincerely,
Bill Owens, President
General Comments
1. The GEC agrees with
the OIG position that the toxaphene analytical method used since 1993 by EPA
Region 4 is not effective for detection of toxaphene in environmental
samples, including soil, water, and fish.
2. The method of
toxaphene analysis used by EPA Region 4 and Hercules, commonly called the
Toxaphene Task Force (TTF) method and Hercules Protocol, failed to identify
and measure toxaphene at levels meaningful to protection of public health
and the environment. Data produced since 1993 for the Hercules 009 Landfill
Superfund Site (Site) is not appropriate for remedial decision-making.
Areas were delineated for removal or solidification at the Site were based
upon data of insufficient quality, which call into questions protectiveness
of the remedy. Data produced by the TTF method either failed to identify
toxaphene present, or seriously underestimated the amount present.
3. The GEC agrees with
the OIG that if human health at the Hercules 009 Landfill Superfund Site
and/or surrounding areas was threatened because the analytical method used
to test for toxaphene underestimated the amount of toxaphene, then all areas
sampled by the TTF or Hercules Protocol methods should be re-sampled by
Negative Ion Mass Spectroscopy (NIMS).
Chapter 1 -
Introduction
4. Demonstrating an
understanding of the Hercules 009 Landfill Superfund Site’s (Site) history
and landfill contents is a very important step in preparing to make a
determination about the protectiveness of the removal actions and
containment activities. The following comments are made to correct
inaccurate information presented in the OIG Report concerning the Site.
Site
Information
Part
of the Hercules 009 Landfill was also used for disposing empty toxaphene
drums and toxaphene-contaminated glassware, rubble, and trash.
(emphasis added)
5. Full drums were
encountered during In-Situ Stabilization of the Site. Workers present
reported that many of the full drums encountered were breached during the
remedial action, and a few were over packed and removed. Off-grade
toxaphene was reportedly disposed in the Site. The observations of the
workers present during remedial activities are consistent with reported
disposal of off-grade toxaphene at the Site. The OIG Report should be
corrected to reflect that empty and full drums were disposed of in the Site,
which is documented in the Site record.
The
GEPD monitored the Hercules 009 Landfill while it operated.
6. The OIG report
acknowledges that the Georgia Environmental Protection Division (GEPD)
monitored the Site but fails to mention sampling results, and the reason for
revocation of the Site Hazardous Waste Disposal Permit, and listing as an
EPA Superfund Site. The GEPD reported toxaphene sampling results from
their Site monitoring in the April 22, 1980 Report - Off-site
Contamination.
|
|
3-6-80 |
|
3-6-80 |
|
3-14-80 |
|
|
Soil |
|
Water (surface) |
|
Water (surface) |
|
Perimeter ditch #1 |
65.5
PPM |
|
0.005 mg/l |
|
0.0076 mg/l |
|
Perimeter ditch #2 |
55
PPM |
|
0.005 mg/l |
|
N/A |
|
Culvert |
435
PPM |
|
0.1 mg/l |
|
0.025 mg/l |
The Site was closed due
to migration of toxaphene from the landfill cells to ditches, culverts, and
surface waters. Areas of concern that led to the National Priority List
listing of the Site and identified for removal in the Record of Decision
remain at the Site. Most notable are the culvert bank that adjoins the Site
and toxaphene manufacturing sludge located below the water table.
The
site is a 16.5 acre property, although the landfill occupies only 7 acres on
the north end of the property.
7. A Superfund site is
defined by the extent of contamination above remedial action goals, and not
property boundaries. The Site includes the Benedict Road neighborhood,
Altama Elementary School, and areas along Spur 25. These areas will need to
be included in soil sampling to evaluate the removal action based upon data
produced by the TTF and Hercules Protocol methods (a.k.a. August 17, 1997
method).
In
the forested area in the southeastern part of the site, outside of the
protectively capped area, is a storage shed near a small pond.
(emphasis added)
8. No data has ever been
produced to support the statement that the Site is protectively capped. To
the contrary, the Record of Decision (ROD) mandated cap was never
constructed, nor was the cap mandated in the Explanation of Significant
Differences (ESD). The Site cover that was constructed is composed of
toxaphene contaminated soil from removal actions in the Benedict Road
neighborhood, Altama Elementary School, along Spur 25, and previously
excavated soils from drainage ditch maintenance, which was placed on the
cells and mixed with a little cement. Protectiveness of the Site cover is
questionable since no confirmation sampling has been conducted. Toxaphene
in soil consolidated during removal actions and used to cap the Site was
analyzed by the method the OIG has identified as inappropriate, and actual
levels of toxaphene were likely under-reported.
The remedial action
involved stabilizing the site and constructing a landfill cover,
which was then covered with clean fill material that was graded to promote
adequate drainage, and seeded with grass.
(emphasis added)
9. The remedial action
was far greater in scope than stabilizing the Site and constructing a
landfill cover. The remedial action included soil removal of
toxaphene-contaminated areas to the east that included Altama Elementary
School and the Benedict Road neighborhood; areas to the south that included
the entry road to the landfill cells and Benedict Road to Altama Avenue; and
areas to the west along Spur 25. Migration of toxaphene was extensive
around the Site. The mechanism of toxaphene transport and migration
identified by Hercules was sloppy handling of manufacturing sludge during
landfill construction. The TTF method found toxaphene at 1800 ppm on Altama
Elementary School property, several hundred feet from the landfill cells.
Of particular concern is how toxaphene migrated across a culvert and
hundreds of feet onto Altama Elementary School property. The findings of
the OIG should include recommendations to retest all areas previously tested
by the Toxaphene Task Force (TTF) method, with Altama Elementary School
identified as a priority.
Background Information on
Toxaphene
As manufactured, the
original toxaphene pesticide was a mixture of more than 200 closely related
chlorinated organic compounds.
This original toxaphene
pesticide mixture is commonly known as “technical” toxaphene. Technical
toxaphene consists mainly of polychlorinated bornanes with between six to
nine chlorines attached.
10. The Report fails
accurately to define toxaphene and becomes embroiled in a discussion of
technical toxaphene, weathered toxaphene, and degraded toxaphene.
Toxaphene is one of the names by which Hercules marketed their invention of
a Polychlorinated Camphene (PCC) that was awarded patent number 2,565,471 on
August 28, 1951. The patent clearly defines what constitutes PCC that was
marketed under many names including toxaphene.
The
PCC mixture patent protected by Hercules included, “Any polychloro camphene
containing from about 40 to about 75% of chlorine …,” or any camphene
compounds with between 3 and 9 chlorines, and identified these compounds as
the toxic ingredients of the invention. Regardless of the term used to
described freshly manufactured toxaphene, weathered toxaphene, or degraded
toxaphene, all are the polychlorinated camphene (PCC) that comprised the
toxic component that was patent protected. Only after camphene contains
less than 3 chlorines can it be described as a degradation product.
Literature describes toxaphene or PCC as camphene with an average of 67% to
69% chlorine by weight, and is a complex mixture of over 670 separate
chemicals.
[1],[2],[3]
The numerous names and definitions used in the OIG Report are all the PCC
patent protected by Hercules, unless the camphene contains less than 3
chlorines.
The chemical of concern at the Site is PCC remaining in the manufacturing
waste and off-grade product disposed in the Site. A discussion that
attempts to differentiate technical toxaphene, degraded toxaphene, or
weathered toxaphene are inappropriate since they all are toxaphene and are
the chemical of concern at the Site, which is PCC. To infer that toxaphene
is mainly polychlorinated bornanes with 6 to 9 chlorines attached is
inconsistent with the product patented by Hercules.
PCC
is known to produce an almost endless pattern of peaks when analyzed by Gas
Chromatograph/Electron Capture Detector (GC/ECD). The variability of GC/ECD
peak patterns for PCC can be observed between laboratory calibration
standards purchased from different suppliers, yet they all are PCC.
Variations in GC/ECD peak patterns can be observed between Electron Capture
Detectors (ECD), yet they all are indicating the presence of PCC. GC/ECD
temperate settings can produce variability in peaks, but the peak patterns
still indicate PCC. GC/ECD patterns can also vary because PCC is known to
undergo dechlorination, making some peaks smaller, most notably in the back
half of the chromatogram, and larger in the front half of the chromatogram,
but the compounds being observed are still PCC. Dechlorination of the most
chlorinated camphene compounds, most notably camphene with 8 or 9 chlorines,
is well known and has been documented numerous times in literature.
Dechlorination can take place for a number of reasons but the decrease in
back, and increase in front, chromatogram peaks do not indicate a different
compound but rather a change in PCC ratios.
These breakdown products are a different mixture than the original mixture,
so it appears different to the testing instruments.
11.
How PCC mixtures appear to instruments is irrelevant to identification and
quantification. Regardless of the ratio of the 670 plus variations of PCC
present, it is still PCC. Hercules patent-protected a general recipe of
polychlorinated compounds and did not specify any ratio of individual
congeners. For this reason, the relative height of individual peaks in the
standard is irrelevant to the peaks in the sample being analyzed and
identified as PCC. All PCC with a chlorine content from between about 40%
and about 75%, or between 3 to 9 chlorines, are the PCC compounds patented
by Hercules and can be called toxaphene. PCC compounds that contain less
than 3 chlorines can be called degraded PCC or degraded toxaphene.
Chapter 2 - The Groundwater Should be Tested for Toxaphene Breakdown
Products
12. General Comment – The title of Chapter 2 should read “The Groundwater
Should be Tested for Toxaphene and Toxaphene Breakdown Products.” As long
as the PCC contains 3 or more chlorines attached to camphene, it is
toxaphene or PCC. PCC with less than 3 chlorines attached to bornanes, or
camphene, would constitute a toxaphene breakdown product. The GEC agrees
that the Site monitoring program should identify any potential toxic
transformation products and toxaphene. Since very little toxicological
information is available about the 670 plus compounds that comprises PCC,
and even less about any potential toxaphene transformation products, a very
conservative approach should be used.
Until
EPA knows whether the groundwater is contaminated by toxaphene breakdown
products, it will be unable to definitively determine if the cleanup for the
Hercules 009 Landfill protects Human Health.
13. The Report does not
differentiate between cleanup and containment at the Site. Cleanup, or soil
removal-action activities, took place outside the 7-acre area where the
landfill cells were located. Containment, or Ex-Situ Stabilization, took
place in the 7 acre area where PCC manufacturing wastes, off-grade product,
and trash were disposed in the former Spur 25 borrow pit. The Report is
confusing in that it implies that the testing the groundwater within the
16.5-acre Site will determine if the cleanup, or soil removal actions, of
areas outside the Site property boundary are protective of human health.
Both soil cleanup and
containment activities were based upon PCC analysis that the Report
identified as inappropriate. The EPA will be unable to determine
definitively if removal actions in the Benedict Road neighborhood, Altama
Elementary School, and other areas protect human health until soil sampling
takes place. The data that were used to delineate removal actions relied
upon the same analytical method the OIG has identified as inappropriate.
All data produced since 1993, which included the decision-making data for
the soil removal actions, remedial design, remedial action, and delineation
of areas for Ex-Situ Stabilization are of no value in making a determination
about protectiveness to human health and the environment.
In
the case of Hercules 009 Landfill, the surrounding groundwater is being
periodically tested for the original toxaphene mixture put in the site
between 1975 and 1980.
14. The original
toxaphene mixture placed in the Site has not been definitively identified.
What is now being described, as weathered or degraded toxaphene, could be
what the original waste mixture looked like on a chromatogram when disposed
in the Site. The Report appears to be stating that Site groundwater has
been periodically tested, but fails to state that the TTF and Hercules
Protocol methods were used, which the OIG has now identified as
inappropriate. The TTF and Hercules Protocol methods based identification
on the presence of at least four peaks in the back half of the chromatogram
with ratios the same as the analytical standard being used. PCC was not
identified or quantified unless at least four peaks were present. OIG
Report Figures 1, 3, 4, and 5 graphically demonstrate that four peaks in the
same ratio were not present in the sample and standard, and therefore PCC
was not reported as present. The quantification methods used are not the
same as EPA Method 8081. A trained chemist can confidently state that PCC
is indicated and quantify “total toxaphene” or “apparent toxaphene”, even if
there have been decreases in late PCC peaks and increases in early PCC
peaks, when EPA Method 8081 is properly applied. The underlying problem at
the Site is that the TTF and Hercules Protocol methods were used to indicate
the presence of PCC instead of EPA Method 8081. Numerous laboratories flag
analysis with TTF or Hercules Protocol instead of Method 8081 since they
recognize the methods are different and consistently produce very different
results. The Agency for Toxic Substance and Disease Registry is specific as
to why the TTF and Hercules Protocol methods are not the same as EPA Method
8081.
Testing
for Toxaphene Breakdown Products Is Needed
EPA’s Method Fails to Identify Toxaphene Breakdown Products in Groundwater
15. General Comment –
While testing for toxaphene breakdown products is needed, the primary
problem at the Site, and underlying reason there are concerns about the
protection of human health, is the TTF and Hercules Protocol methods fail to
identify toxaphene. Repeatedly, methods used at the Site have been
demonstrated either to fail to detect or to underestimate seriously the
amount of PCC present in soil, seafood, and water.
Using a Different Method
Would Identify Breakdown Products
When the OIG looked at
the groundwater monitoring data for evidence of toxaphene breakdown
products, the OIG found some evidence suggesting that toxaphene breakdown
products may be in the groundwater surrounding the Hercules 009 Landfill
site.
16.
The OIG’s observation that PCC was present when none was reported by the TTF
and Hercules Protocol methods is the same conclusion other studies have
reached and confirmed though analysis. The OIG suggesting that the observed
compounds might be “toxaphene breakdown products” in inappropriate since the
compounds observed are most likely part of the PCC mixture patented by
Hercules. The patent did not specify a particular ratio of individual PCC
compounds as patent protected toxic components. Many of the prominent
PCCs found in the front half of the chromatogram are associated with
unmodified toxaphene or PCC as manufactured by Hercules.
[4],[5],[6],[7]
Without
such definitive data, any determination on the effectiveness of the cleanup
remedy is inconclusive.
17. The GEC agrees with
the OIG that definitive data is needed to evaluate the cleanup of the
Benedict Road neighborhood and Altama Elementary School, and other areas
where soil removal actions took place. Likewise, the effectiveness of the
containment remedy will be inconclusive until definitive data is produced
that demonstrates the action levels specified in the Record of Decision
(ROD) have been obtained at the Site. Without completion of the
confirmation sampling specified in the ROD, attainment of remedial action
goals cannot be demonstrated.
A
new analytical method using Negative Ion Mass Spectroscopy (NIMS, or called
the new method hereafter) should be used to test for toxaphene breakdown
products in groundwater.
18. The GEC agrees with
the OIG Report in that NIMS should be used to test for PCC breakdown
products in groundwater. In addition, NIMS should be used to test for PCC
and PCC breakdown products wherever the TTF and Hercules Protocol methods
were used to analyze soil, air, seafood, surface water, and groundwater.
Therefore,
the use of the new techniques for groundwater monitoring at the Hercules 009
Landfill site provides the certainty needed to determine whether the
groundwater is contaminated by toxaphene breakdown products.
19. Use of NIMS is also needed to provide the certainty needed to determine
if PCC and PCC breakdown products are still present in areas where soil
removal actions took place, particularly the Benedict Road neighborhood,
Altama Elementary School, and the culvert adjoining the school.
Region
4 Is Concerned about Using the New Method
Region
4 officials are concerned about using the new (or NIMS) method to test
groundwater at the Hercules 009 Landfill because the method is not approved
by EPA.
20.
The two methods used at the Site, TTF and Hercules Protocol methods, were
not SW-846 approved for use by the EPA. EPA-approved methods are set forth
in EPA publication SW-846, and the prescribed method was Method 8081. The
NIMS method has been used and documented in peer reviewed scientific
journals numerous times since at least 1987.
The
EPA conventional method (method 8081) was validated. Consequently, EPA
knows the results will be accurate when Method 8081 is used to test for the
original toxaphene mixture.
21. While the statement
is true that EPA Method 8081 was validated, it is not the analytical method
used at the Site. Method 8081 has been used for many years to test for PCC
and quantify the indicated total or apparent PCC present. When Method 8081
and the TTF or Hercules Protocol methods are compared side-by-side, Method
8081 reports toxaphene present and at substantially higher levels than the
TTF and Hercules Protocol methods, which either fail to detect or
substantially under-quantifies PCC present. The TTF and Hercules Protocol
methods are NOT Method 8081.
The
OIG agrees that using an EPA-approved method is better than a method not
approved by the EPA. However, EPA has no approved method to identify
toxaphene breakdown products.
22.
The GEC agrees that EPA-approved methods should be used. The use of NIMS
will eliminate the ambiguity, doubt, and confusion associated with the TTF
and Hercules Protocol methods. The inherent weakness with EPA Method 8081
was an inability to definitively identify the compounds present. In order
to compensate, Method 8081 recommends confirmation by Mass Spectroscopy
(MS). Utilization of NIMS in conjunction with Method 8081 is consistent
with established EPA SW-846 protocols and would definitively identify PCC
and PCC breakdown products.
Recommendations
23. General Comments –
The GEC agrees with the OIG’s recommendation to test groundwater at the Site
for PCC. But OIG recommendations must go further to protect human health.
Testing Site groundwater is a limited measurement of the containment part of
the remedy but does not address the soil removal action parts of the
remedy. The same shortcomings identified with groundwater testing apply to
the data used for the decision-making process for soil removal actions. Data
collected by the TTF and Hercules Protocol methods have been documented to
significantly underestimate or to fail to identify PCC present.
The OIG should recommend
that all soil, surface water, groundwater, and seafood samples analyzed by
the TTF or Hercules Protocol methods be analyzed by an appropriate method
such as NIMS. If PCC compounds are found at the Site, appropriate action as
specified in the ROD should be taken to protect human health.
Agency Comments and OIG
Evaluation
Region 4 later provided
results of analytical testing they had performed using EPA method 8081.
Their results showed significantly more toxaphene in one well (N-11) at the
site.
24. EPA Region 4 has
stated that no toxaphene has been detected in groundwater at the Site and
has repeatedly cited this as the reason the ROD mandated remedy need not be
implemented. Toxaphene has been found historically and continues to be
found in groundwater at the Site.
As discussed in Appendix
C, the quality control does not adequately show that the substances to be
measured were not destroyed when the samples were prepared.
25. Sample preparation
and GC/ECD injector temperatures are suspected to remove, dechlorinate, or
even destroy PCC in the samples.
Region 4 proposed two
interim strategies to assess the risk to human health posed by the toxaphene
breakdown products, which they called weathered toxaphene.
26. Region 4 has failed
to demonstrate an understanding of PCC and has developed a wide range of
terms, words, and definitions for the PCC mixture patented by Hercules. The
PCC Region 4 calls by numerous descriptive terms fall under the patented
product. PCC breakdown compounds, which are chlorinated camphene with less
than 3 chlorines, should be clearly defined as such. The term “weathered
toxaphene” used by Region 4 is ambiguous, and should not be used.
We evaluated the proposed
strategies, and believe the strategy using toxicity criteria for toxaphene
is inappropriate because the toxicity of weathered toxaphene could be
significantly different.
27. The GEC agrees with
the OIG in that different ratios of PCC compounds will have different
toxicological properties, and the precautionary principle should be applied.
The term “weathered toxaphene” is very ambiguous and appears to be linked to
an undefined peak profile for PCC. The definition of toxaphene, as stated
in the Hercules patent for their PCC invention, is any peak ratio of
camphene with 3 to 9 chlorines; and all PCC that falls within this
definition should be simply called toxaphene or PCC.
Chapter 3 – Reporting on
the Cleanup’s Effectiveness Was Not Timely
28. General Comments -
The OIG identified the need to determine if the remedy is operating as
intended and still protects human health and the environment. The soil
removal actions took place outside the Site property boundary, and sampling
groundwater will not, by itself, provide information needed about the soil
removal actions that were originally based, it should be recalled, upon soil
data analyzed by a method the OIG has identified as inappropriate. This
fact undermines the conclusions of the OIG Report that the remedy is
operating as intended.
Review Must Occur Every 5
Years
…
the purpose of the 5-year review was to evaluate, through data gathering and
observation, how well the site’s remedy is working.
29. The OIG correctly
found that the TTF and Hercules Protocol methods used to analyze the Site
were inappropriate. Without reliable data to make scientifically sound
evaluations, questions regarding the Site remedy working will not be
answerable. Appropriate sampling and analysis of soil and groundwater are
needed to complete the Five-Year Review.
Question
A – Is the remedy operating as intended by the decision documents?
Question B – Are the
exposure assumptions, toxicity data, cleanup levels, and remedial action
objectives used when the remedy was selected still valid?
Question C – Has any
other information come to light that could call into question if the remedy
protects human health?
30. The OIG focused on
Question B, and concluded that remedial action objectives would not have
been met if toxaphene is found in the groundwater. The same is true if soil
remediation goals were not met in the soil removal actions, which were based
upon analytical methods now known to be inappropriate. However, key to
meeting the remedial objectives is answering Question A regarding
implementing the decision documents, and Question C regarding information
that could call into question protectiveness of remedy to human health and
the environment. The data that formed the basis of decision-making for the
Remedial Design and Remedial Action were seriously flawed, the reality of
which the OIG has identified as a significant problem. Based upon the
flawed data, EPA Region 4 made a decision not to implement the ROD.
Specific deviations from the ROD in conjunction with PCC analysis by the TTF
and Hercules Protocol methods call into question protectiveness of the
remedy to human health and the environment. The following components of the
ROD must be evaluated in order to determine if the remedy is working as
intended.
A. Performance Standards
The Performance Standard of 76 PPM toxaphene for
subsurface soils was established as a remedial action goal for the source
areas to protect surface water and groundwater at the Site.[8],
[9] It was anticipated
that contaminants at the Site which do not have cleanup levels presented in
the ROD would be reduced to acceptable levels when cleanup levels were met
for the most toxic and most mobile contaminants for which cleanup levels
have been established.[10]
The EPA assured the community that the cleanup goal of 76 ppm toxaphene for
subsurface soils would be met by either stabilization or chemical
extraction.[11]
The treatment method, In-situ Stabilization, was selected because it would
reduce the incremental risk associated with current Site conditions by
permanently treating all affected solids having constituent concentrations
exceeding remedial action levels.[12]
In addition, by treating the soil in place, or In-Situ, the public and the
school children at Altama Elementary School adjoining the Site would be
further protected from fugitive emissions during the Remedial Action. The
EPA specifically and repeatedly assured the community that In-Situ would be
conducted without excavating the contents of the landfill at the pre ROD
meeting.
The EPA has made a fundamental change in the scope and
performance of the subsurface soil Performance Standard of 76 ppm toxaphene
by changing the Performance Standard to the water table; and has
fundamentally changed the cost of treatment by reducing volume to be
treated. Furthermore, the Performance Standard change was fundamental since
it does not enhance its protectiveness, or effectiveness.[13]
The OIG Report failed to evaluate colloidal transport of toxaphene to
neighboring properties, or discuss the implications of leaving untreated
toxaphene sludge and contaminated soils below the groundwater table. Areas
adjoining the Site, such as the culvert bank, identified for soil removal
actions have not been remediated.
EPA
Region IV contends that when the regional groundwater table is reached, they
have met the intent of the ROD and the ROD did not contemplate extensive
groundwater de-watering which would be necessary to treat below the regional
groundwater table.[14],
[15],
[16], Contrary to
contentions of the EPA, de-watering was contemplated and discussed in the
Feasibility Study.[17]
The Remedial Investigation clearly shows the sludge extended into the
observed groundwater table.[18]
The authors of the ROD understood the sludge extended into the groundwater
table,[19]
and the Site was deeper than historical records indicate.[20]
It is accurate to say the ROD did contemplate treatment below the water
table but left the engineering specifications to be worked out in the
Treatability Study using the Performance Standard of all subsurface soils
exceeding the Performance Standard of 76 ppm toxaphene. The EPA has
concluded previously that In-Situ Stabilization is an effective remedial
technology and would achieve the performance criteria specified in the ROD
for this Site.[21]
The OIG Report did not mention that toxaphene sludge depth data from the
Treatability Study and Supplemental Soil Analysis could be used to estimate
the volume of source areas that were left untreated. Data concerning the
amount of sludge and contaminated soil left untreated will be needed to
evaluate the potential for continued colloidal transport of toxaphene to
neighboring properties.
B. Treatment Volume
The change to subsurface soil Performance Standard
fundamentally reduced the treatment volume. Eliminating source areas to be
treated as determined by the methodology specified in the ROD fundamentally
changes the volume to be treated and is a fundamental change in scope,
performance, and cost. Subsurface soil target concentrations were used to
establish treatment boundaries for subsurface soil and wastes for cost
estimating purposes and a sampling program was conducted to determine the
actual volumes of surface soil and subsurface soil requiring remedial
action.[22]
The ROD specified a sampling program to determine the actual volumes of the
source areas to be treated, and not the groundwater table. If the
groundwater table was to be used as the remedial boundary, all necessary
data to determine source area volume would have been present at the time the
ROD was written. The use of soil-driven standards was further clarified in
the ROD; "Sludge and soil containing toxaphene exceeding remedial action
target concentrations will be treated in-situ in conjunction with
stabilization of consolidated surface soil". By their own admission, the EPA
did not expect excavation to meet the Performance Standard or use the
methodology specified in the ROD to determine treatment boundaries of source
areas.[23]
The ROD is clear: the subsurface soil target concentrations were to be used
to establish vertical and horizontal treatment boundaries for subsurface
soils and waste, and a sampling program conducted to determine the actual
volumes of surface soil and subsurface soil requiring remedial action.[24]
A sampling program, not the water table, was to be used to determine the
boundaries of the source areas designated for treatment. Sampling required
under the ROD was conducted to determine the vertical and horizontal
boundaries of the source area to be treated during the Treatability Study.[25]
Discarding the delineated source areas identified for treatment in the
Treatability Study, a decision document for the Site, is a fundamental
change to the scope, performance, and cost of the remedy selected in the
ROD.[26]
The
Five-Year Review did not consider the Treatability Study or the Summary
Report for Supplemental Soil Analysis at the 009 Landfill.
[27] Treatability studies
and the Remedial Investigation consistently and repeatedly found toxaphene
sludge deeper than the historical descriptions of the landfill cells. It is
conspicuous that the OIG did not mention that significant source areas did
not undergo the remedy specified in the ROD. The OIG conclusion that the
remedy is protective is based upon a very limited subset of documents
supporting contentions that the Site Remedial Action is protective. When
the Administrative Record is examined as a whole, data refutes contentions
in the OIG Report that the Site is not a continuing hazard and risk to human
health and the environment.
C.
Treatment Method
Fundamental changes were made to the ROD specified
treatment method of In-Situ Stabilization, to stabilization of only source
areas above the water table to form a cap over the site.[28],
[29] The fundamental
change in the treatment method made by the EPA also changed the performance
and scope of treatment because of the limitations identified with excavation
at the site.[30]
In addition, cost of treatment changed by a reduction in the soil volume
determined during the Treatability Study using the ROD guidelines. An
amendment to the ROD is required when changes do not enhance protectiveness
or effectiveness, reduce scope, performance, cost, and are a fundamental
reconsideration of the basic remedy selection decision on which comment was
taken.[31]
The
EPA called the treatment method In-Situ and assured the community that
stabilization would take place below ground, while remedy actually excavated
the entire contents of the Site down to the water table. All descriptions
of the Remedial Action by the EPA describe Stabilization with extensive
excavation, contrary to the assurances given to the community.[32],
[33],
[34],
[35] Inherent problems
identified with excavation at this Site in the RI/FS re-emerged.[36]
Contrary
to the contention of the EPA, all toxaphene sludge was not treated because
sludge extends below the regional groundwater, and treatment was stopped
before, or when, the groundwater table was reached. Water table elevations
at the site range from 14 to 17 feet MSL (Mean Sea Level)[37]
and the sludge extends down below 10 feet MSL.[38]
The water table Performance Standard and capping the Site alters scope,
performance, and cost.
The
cap will not prevent transport of contamination into the groundwater because
source areas exist in soils above Performance Standards over 12 feet below
the water table. In addition, horizontal groundwater flow will continue to
allow colloidal migration of contamination from source areas throughout the
subsurface soils.[39]
A "Cap" is a fundamental change to the remedy selected in the ROD that does
not enhance performance or effectiveness, and changes the scope, performance
and cost.
D. Confirmation Sampling
Confirmation sampling to confirm compliance with the
ROD and protectiveness of the remedy was mandated by the ROD, but changed to
only if excavation did not reach the water table.[40]
Elimination of confirmation sampling specified in the ROD is a fundamental
change in the scope, performance, and remedy selection decision process in
which public comments were taken. The change does not enhance protectiveness
or effectiveness and cannot be handled by an Explanation of Significant
Differences.[41]
The
EPA magnified uncertainties already associated with In-Situ. Uncertainties
associated with In-Situ stabilization are the variability of the treatment
throughout the treatment zone and incapability of the contractor to monitor
treatment results. These concerns were addressed in the ROD by requiring
sufficient overlap between treated areas and by post-treatment sampling of
the treated zone and underlying soil.[42]
The Remedial Action did not conduct the ROD specified post-treatment
sampling required and further expands the uncertainties associated with the
selected treatment. The OIG Report contends that the remedy is protective
based upon opinion, speculation and hearsay, not the data specified in the
ROD to evaluate the completed Remedial Action.
Changes
in treatment volume and treatment method resulted in the underlying soil,
for a depth of up to 12 feet, not meeting Performance Standards.
[43] Levels up to 2600 PPM
remain in the soils below groundwater level.[44]
Fundamental changes to confirmation sampling do not enhance protectiveness
or effectiveness and fundamentally change the scope and cost.
The draft Five-Year Review confirms that colloidal transport of toxaphene is
taking place at the Site, but did not discuss the migration rate or how
untreated sludge and soil could contribute to continued colloidal transport
off-site to neighboring properties. Failure of the OIG to evaluate past
and current colloidal transport leaves considerable doubt about
protectiveness of the remedy to neighboring properties. Extensive migration
of toxaphene took place on and around the Site. The PRP identified the
transportation mechanism responsible for migration on site and off site to
the Benedict Road neighborhood, and to Altama Elementary School, as handling
techniques used during landfill construction and dredging of the adjoining
culvert. The ROD included the culvert adjoining the Site in the areas
identified for remedial action, which has not been done. The area between
the landfill cells and the culvert are a significant source area that has
not been remediated.
E. Landfill Cap
Elimination of the clay component of the cap is a
fundamental change that does not enhance protectiveness or effectiveness and
cannot be handled by an Explanation of Significant Differences because it is
a fundamental change in the scope, performance and cost of the remedy
selected in the ROD.[45],
[46] Furthermore, the
treatment of consolidated contaminated soils with 3% Portland cement is a
fundamental change from formulations approved in the Treatability Study
(TS). No Treatability Study was performed on the 3% Portland cement
formulation. The proposed treatment is in non-compliance with the
Treatability Study, a Decision Document for the Site. Therefore, the
treatment is a fundamental change in the remedy and treatment methodology
specified in the ROD. The cap treatment does not enhance performance or
effectiveness and changes the scope, performance, and cost of the selected
remedy.
The OIG Report should have mentioned that the ESD mandated Site cap of
consolidated off-site removal action soils that were to be screened and
mixed in a pug mill before being applied to the site was never implemented.
In actuality, contaminated soil was placed on top of the Site and mixed with
some cement. No confirmation sampling has been done to evaluate the
ability of the contaminated soil placed on the landfill to resist rainwater
infiltration. The placement of soil over the site and mixing cement, which
is in non-compliance with the ESD, could result in a significant decrease in
effectiveness. Significant also is that the OIG Report failed to note that
neither the ROD nor ESD specified covers were constructed at the Site. To
the contrary, the OIG states the site is protectively capped, which is not
supported by any data.
F. Explanation of Significant Differences
The draft Five-Year
Review Summary Form, under Issues, states that the August 1998 Explanation
of Significant Differences (ESD) provided adequate explanation for the
changes made to the ROD concerning depth of excavation. The ESD states that
there will be “hydrostatic inflow”, “blow-in”, “unsafe working conditions”,
and “side sloping”, if the remedy specified in the ROD is followed.
Presumably the safety concern stems from a reported upwelling of water under
the site. The EPA requested study and quantification of this reported
phenomenon by Hercules that was so dangerous in 1996. No data has been
produced to support the contention that water upwelling occurs under the
Site. The premise of the ESD is not supported by Site data. To the
contrary, the EPA and RP have never explained how toxaphene migrated deep
into soils underlying the Site against upwelling water. The OIG Report
relies heavily on the EPA Region 4 hydrologist’s evaluation of the Site,
which does not indicate in any way that water upwelling is occurring or has
occurred at the Site.
Under CERCLA, supporting
documentation for an ESD must be placed in the Repository for public
reading. No documentation has been produced by the EPA or PRP to support
the claims made about potential disastrous construction conditions described
in the ESD. The ESD is no more than a collection of rumors and hearsay that
are not supported by Site data. A more likely scenario is that the ESD was
written in support of agreements made between the EPA and Hercules during
1996, 1997, and 1998. There is documentation in the Administrative Record
to support this scenario, whereas there is none to support the ESD.
The ESD fundamentally
changed In-Situ remedy specified in the ROD to excavation and treatment,
which reintroduce the need for dewatering with excavation identified in the
Feasibility Study. The draft 5-Year Review accurately reports the Remedial
Action for the Site as excavation, a fundamental change in the ROD.
EPA
Region IV contends that when the regional groundwater table is reached, they
have met the intent of the ROD; the ROD did not contemplate extensive
groundwater de-watering which would be necessary to treat below the regional
groundwater table.[47],
[48],
[49], Contrary to
contentions of the EPA, de-watering was contemplated and discussed in the
Feasibility Study.[50]
The Remedial Investigation clearly shows the sludge extended into the
observed groundwater table.[51]
The authors of the ROD understood the sludge extended into the groundwater
table,[52]
and the Site was deeper than historical records indicate.[53]
It is accurate to say the ROD did contemplate treatment below the water
table but left the engineering specifications to be worked-out in the
Treatability Study using the Performance Standard of all subsurface soils
exceeding the Performance Standard of 76 PPM toxaphene. The EPA has
concluded previously that In-Situ Stabilization is an effective remedial
technology through onsite stabilization with vertical augers that did
achieve the performance criteria specified in the ROD for this Site.[54]
The EPA agrees that the remedy implemented at the Site was Ex-Site
Stabilization, and not the In-Situ stabilization required under the ROD.
[55]
The extensive changes to the effectiveness, protectiveness, scope, and
performance of the Site remedy leaves considerable doubt about the efficacy
of the remedy, which is further exacerbated by the analytical methodology
used during the decision-making process that the OIG has identified as
inappropriate.
Further Definite
Information is Needed
Between
the first draft report of the 5-year review and the most recent one, the
conclusion on the cleanup’s effectiveness changed; we agree with the Corps’
original conclusion that additional information is needed to responsibly
make a determination.
However, it also stated
that the data being collected was not appropriate to determine if the
cleanup is functioning.
31. The GEC agrees with
the OIG that additional information is needed to make a determination about
the cleanup’s effectiveness, and if the on-site containment is operating as
intended. Data used to complete the Treatability Study (TS), Remedial
Design (RD), Remedial Action (RA), and follow-up confirmation sampling for
off-site removal actions were based upon data produced by the TTF and
Hercules Protocol methods. The OIG report correctly identifies the need for
additional information, but did not recommend sampling and analysis needed
to evaluate the TS, RD, and RA decision-making process, or protectiveness of
the off-site removal actions.
However,
the subsequent sentences in the first paragraph of the determination
(draft 5-year review) were deleted, including the caveat about the data:
…data being collected is not appropriate to determine if the remedy is
functioning as intended by the ROD. Groundwater data from the monitoring
well network at the site does not appropriately represent the concentration
of total toxaphene present in the ground water.
32.
The findings of the Corps underscores that the TTF and Hercules Protocol did
not report total toxaphene results needed to evaluate protectiveness of the
remedy to human health and the environment. Efforts of EPA Region 4 to
delete this section indicates that Region 4 understood that the TTF and
Hercules Protocol methods were not equivalent to EPA Method 8081, which is
used to report total toxaphene and apparent toxaphene. The EPA Region 4
chemist, who also participated in the development of the TTF method, noted
that the "latter peaks" in samples were decreased and the "early peaks" were
increased in environmental samples from Brunswick, and that the TTF method
may seriously underestimate the true concentration of toxaphene.
[56],[57]
The Georgia Environmental Protection Division chemist that participated in
development of the TTF method noted that unknown peaks not quantified may
have been toxaphene related and the total area method was not used when the
TTF method was applied.
[58]
It is very unusual that analysis is conducted and chemical compounds present
are not reported, as with the TTF method. Sound analytical methods,
intended to protect human health and the environment, include the reporting
of unidentified compounds when they are encountered.
However, since additional
actions were taken to ensure that the community around the site is not
exposed to groundwater, we agree that the remedy is effective.
33.
The GEC disagrees with the OIG solely using groundwater as the measure of
the remedy’s effectiveness. The remedial decision-making process was based
upon data the OIG has identified as inappropriate, which was also used to
delineate areas for soil removal actions and to confirm the soil remedial
action goals had been achieved. The toxicologist with the Agency for Toxic
Substance and Disease Registry (ATSDR) noted that use of the "back half"
peak method (TTF method) is likely to result in significant underestimation
of PCC concentration, and the estimated dose could be 10 times higher if
historical data are taken into account for dose estimation.
[59]
The interview with Dr. Keith Maruya for the Hercules 009 Landfill Superfund
Site Five-Year Review resulted in an estimation of toxaphene levels up to 10
times higher than reported by the TTF analytical method. The OIG Report does
not discuss how a determination that the remedy is protective could be made
with admittedly questionable data that was used for the soil removal
actions, RD, and RA decision-making.
Agency Comments and OIG
Evaluation
We
removed the second
(deed restrictions) and third (threat to residential wells) of the
three recommendations because Region 4 provided documentation that (1) the
consent decree was recorded in the records of Glynn County…
34. Institutional
controls such as deed restrictions are an important part of the
decision-making process at site where the remedy is containment and
Monitored Natural Attenuation (MNA), and were mandated as part of the ROD
for this Site. The failure to record deed restrictions for the Site could
have prevented the excavation, drilling, and subsequent severe erosion that
took place at the Site during parking lot construction in the Spring of
2005. The OIG should recommend deed restrictions be recorded for the Site
since recording of the consent decree has been demonstrated as insufficient
to meet the intent of the ROD, which is to prevent reintroduction of
contained wastes into the environment. Also notable is that the EPA did not
receive or approve Site construction plans prior to commencement of work,
which underscores the need and importance of deed restrictions.
A
Region 4 hydrologist evaluated the perimeter monitoring well system and
concluded it is sufficient to evaluate migration of contaminants.
35. The OIG relied upon
the EPA Region 4 hydrologist for an evaluation of the Site perimeter
monitoring well system. Site hydrology is very important since it
determines the placement of monitoring wells and was the stated basis of the
decision-making process that led to a fundamental change in the remedy that
reduced the scope, performance and cost, and formed the basis of an
Explanation of Significant Differences for the Site. The GEC reviewed data
that the EPA Region 4 hydrologist used to determine monitoring wells were
sufficient and that was used by the OIG to support the conclusion that the
remedy is protective.
The following
are quotes from Attachment 4, the December 17, 2004 Memorandum from the EPA
Region 4 hydrologist.
Toxaphene
has not been detected in ground water at the site and remains a non-detect
following the implementation of the remedy.
36. Toxaphene, or PCC,
was routinely detected at the Site as noted in the Remedial Investigation
(RI), Treatability Study (TS), and post remedy sampling. The OIG noted that
recent testing had detected PCC in the groundwater. The OIG’s Report
identified chromatogram peaks suspected to be PCC in groundwater in Figure 5
when the TTF method was used. The Region 4 hydrologist incorrectly reported
that PCC has not been detected in the past or present sampling events.
After the TTF method was adopted, the PCC quantification limit was also
raised from .001 mg/l to .005 mg/l. Implementation of the TTF method is
suspected by the GEC to be the primary reason PCC has not been reported in
groundwater samples, but a five fold increase in quantification limits is
also a significant contributing factor. Combining the opinion of the ATSDR
toxicologist that the TTF method reports 10 times less PCC than is present,
and a five fold increase in quantification limits, significant doubt exists
concerning the accuracy and usability of the water monitoring data for
decisions concerning protection of human health and the environment.
Explain
how the water level contours were constructed. I drew contours of my own
both by hand and using Surfer and could not duplicate RMT’s map. A
discussion of the head perturbations (see Figure in the next page) in the
intermediate and deep zones needs to be discussed in support of the ability
of the monitoring systeim (sic) to detect contamination if it
existed.
37. The Region 4
hydrologist could not take the hydrological data presented and duplicate the
Site hydrology as the Hercules’ consultants reported conditions at the Site.
The data was insufficient to support the ability of monitoring wells to
detect contamination. Basic scientific principles mandate that experimental
designs produce data that are reproducible. Data used by the Region 4
hydrologist did not meet minimal standards of scientifically sound data.
RMT
concludes that the monitoring system is sufficient to detect contamination.
In support of that statement the cross-sections on Sheets 1 and 2 should
include the monitoring wells in order to depict that clearly.
38. The Region 4
hydrologist recognized that further information needs to support the
Hercules consultant’s opinion that the monitoring system is sufficient to
detect contamination. It appears that the Region 4 hydrologist is
supporting the conclusion that the monitoring wells are properly located
upon the consultant’s opinion and not scientifically sound data.
A
discussion of the vertical ground water velocity should be included in the
groundwater monitoring results section. This information is valuable in
substantiating that migration of contamination would be reflected in the
monitoring system if it was indeed occurring.
39. The ability of the
monitoring system to detect contamination is questioned due to the lack of
data concerning vertical groundwater velocity. Lack of vertical groundwater
velocity data continues to be a problem at the Site. The EPA has asked for
data supporting vertical groundwater flow repeatedly before the Remedial
Action, and has asked for it again now to support their contention that the
monitoring wells system is sufficient to detect contamination migrating from
the Site. An Explanation of Significant Differences (ESD) was based upon a
reported vertical groundwater upwelling. The ESD states that there will be
“hydrostatic inflow”, “blow-in”, “unsafe working conditions”, and “side
sloping”, if the remedy specified in the ROD is followed. Presumably the
safety concern stems from a reported upwelling of water under the site. The
EPA requested study and quantification of this reported phenomenon by
Hercules that was so dangerous in 1996. No data has ever been
produced to support the contention that water upwelling occur under the
Site. The premise of the ESD is not supported by Site data. To the
contrary, the EPA and Hercules have never explained how toxaphene migrated
deep into soils underlying the Site against upwelling water. Under CERCLA,
supporting documentation for an ESD must be placed in the Repository for
public reading. No documentation has been produced by the EPA or Hercules
to support the claims made about potential disastrous construction
conditions from vertical groundwater velocity described in the ESD.
Support for disastrous
hydrological blow-in conditions at the Site, if they existed, would have
been encountered during construction of the landfill. Notable is that a
much larger and deeper borrow pit was constructed a few hundred feet to the
west of the Site during the period remedial activities took place. If
hydrological blow-in conditions existed, they would have precluded
construction of the Site borrow pit and the nearby borrow pit.
Interestingly, effects from an extended period of pumping at the nearby
borrow pit are not noted in Site hydrology documents.
The EPA Region 4
hydrologist’s opinion that the remedy is protective and the monitoring
system functioning as intended is not supported by data that meets minimal
scientific standards. Rather, it appears that the hydrologist is repeating
Hercules consultant’s opinion while asking for supporting data. The
request for data quantifying the vertical velocity of groundwater that
supported the ESD has remained unanswered for over 9 years.
The OIG appears to put
great emphasis on the Region 4 hydrologist’s opinion that the monitoring
wells are sufficient since it is quoted. The OIG needs to be sure to
differentiate between opinion and an evaluation supported by scientifically
sound data, and the Region 4 hydrologist’s opinion is not supported by sound
data. Furthermore, the OIG should recommend that a hydrologist outside
Region 4, and preferably independent of the EPA, review Site hydrological
data, determine sufficiency of the monitoring well system, and make
recommendations for any identified Site data needs.
Appendix A - Technical
Discussion on Toxaphene
Both
Hercules Incorporated and the U.S. Environmental Protection Agency (EPA) use
EPA’s analytical method 8081 to test for the original toxaphene pesticide
mixture in the groundwater.
40.
Hercules and the EPA did NOT use EPA method 8081 to analyze for toxaphene in
groundwater and soil, which fact is supported by numerous studies that
compared the TTF and Hercules Protocol methods used at the Site side-by-side
with EPA Method 8081. The TTF method was designed to identify and quantify
toxaphene and some other product which would remain unidentified and not
quantified, which was agreed to at a September 30, 1991 meeting with the
EPA, GEPD, Hercules, and representatives of Law Environmental.
[60]
Instead of "total toxaphene" or "apparent toxaphene" quantified by EPA
Method 8081, which is used by toxicologists in determining the potential
risk to human health and the environment, an agreement was made to develop
another method for identification and quantification of PCC. Prior to
developing another method for the identification and quantification of
toxaphene, the September 30, 1991 meeting participants agreed that methods
used to date had reported apparent toxaphene, also called total toxaphene,
which is produced by correctly applying EPA Method 8081. The report of TTF,
released June 4, 1993, was described as a very limited study of toxaphene
analysis of real samples collected at the Hercules facility in Brunswick,
Georgia.
[61]
EPA Method 8081 was
intended to report total toxaphene and the four peak method was intended to
produce results comparable to the total area method. The TTF and Hercules
Protocol methods do not produce results comparable to the total area method.
The following examples
demonstrate the differences between the TTF and Hercules Protocol methods
and EPA Method 8081.
Example 1
Samples were analyzed by the TTF method, and by the U.S EPA approved
Contract Laboratory Program (CLP) method 8081. Because early and
disproportionate peaks are eliminated from the quantification in the TTF
method, it produces much lower PCC quantification results than the EPA CLP
analytical Method 8081. U.S. EPA Region 4 Environmental Services Division
Laboratory analyzed split samples by the TTF method and a contracted
laboratory by the U.S. EPA approved CLP method 8081. Results showed that
the TTF method either failed to detect PCC or only identified as little as
3.2% of the PCC present.
[62]
Example 2
The GEPD laboratory
analyzed soil samples from the Goodyear Elementary School playground and
reported that toxaphene was not present in the soil samples.
[63]
When analysis was conducted by SW-846 8080 and quantified using the total
area method (total toxaphene), toxaphene was reported up to 64.6 ppm.
[64]
ATSDR
evaluated the data produced by the TTF method and found many concerns over
it use.
[65]
The Hercules Protocol method failed accurately to identify and quantify a
known amount of the PCC in the calibration standard.
[66]
ATSDR has extensively discussed why the TTF and Hercules Protocol methods
are not equivalent to EPA Method 8081.
As
noted in the OIG report, the TTF method also failed to identify PCC in
seafood samples. EPA approved methods have routinely found PCC in fish,
whereas the TTF and Hercules Protocol have consistently failed to detect or
significantly under-quantify PCC present in the samples.
Throughout the Report the OIG should replace reference to EPA Method 8081
with TTF and Hercules Protocol methods, which were actually used at the
Site.
Basics of Toxaphene Chemistry
41.
See Comments 10, 11, and 14 for comments about the basics of toxaphene
chemistry and what is toxaphene and what constitute toxaphene degradation
products.
Technical Toxaphene Degrades in the Environment
Therefore,
technical toxaphene is expected to degrade in the environment and its
degradation is mediated primarily by microbes living in the soil.
42. The GEC agrees that PCC will degrade in the environment under
conditions noted by the OIG. Unfortunately, the Site has not been analyzed
for microbial activity, which would provide useful information about the
efficacy of the MNA remedy.
Evaluating the Potential Risk to Humans from Toxaphene Exposure
Conducting
a detailed and comprehensive risk assessment for the potential exposure to
toxaphene from the Hercules 009 Landfill site is a complex task that is
beyond the scope of this OIG review.
43. Even though the OIG admits risk assessments are complex and beyond the
scope of this review, the OIG goes on to speculate and make sweeping and
unsupported assumptions in this section. Specific concerns about the OIG’s
conclusions follow.
In
general, a major factor needed to evaluate the level of risk to human health
is to determine the major exposure pathways to toxaphene’s degradation
products and to determine all potential sources. The Hercules 009 Landfill
site is just one off the potential exposure routes. …The remaining exposure
routes (i.e. air and soil are practically negligible.
44. The GEC agrees that all major exposure pathways and sources need to be
identified, but the OIG fails to do so, and incorrectly speculates that air
and soil exposure are practically negligible. While the GEC agrees with the
OIG that local fish consumption is a very significant risk factor, PCC
levels higher than at the Site are spread throughout the community. The
following sources of PCC should be considered by the OIG before discounting
other significant chronic exposure routes:
- Hercules Plant: PCC levels in the plant site soils exceed 7%
and are a significant air and soil exposure risk.
- Areas surrounding the Hercules Plant: As previously noted,
toxaphene was found above 64 ppm on an elementary school playground.
Significant source areas are suspected to be present in neighborhoods
surrounding the Hercules plant site.
- Terry Creek Site: Between 2 and 3 million pounds of PCC
manufacturing wastes are estimated to have been released into the estuary,
some of which is in dredge spoil areas that are a potential air exposure
source.
- PCC was reported to be disposed of in the T Street Dump that
is located in the estuary, 4th Street Landfill next to the Glynn
Schools Stadium, and Old Sterling Landfill.
- Hercules has taken depositions from workers concerning
distribution of toxaphene to employees, purchase by Glynn County Parks and
Recreation, and Glynn County Schools for use throughout the community.
The
OIG should clarify that toxaphene and toxaphene degradation products are the
potential chemicals of concern. As previously noted, the PCC patent
protected by Hercules encompasses the vast majority of PCC in Glynn County.
However, five toxaphene congeners (i.e. p26, p50, p40, p41, and p44) are not
readily metabolized and excreted and, thus, can accumulate in the human
body. … To evaluate the level of risk to human health, EPA needs to know
the concentration of these five congeners and their metabolite precursors in
the environment.
45.
The GEC agrees that compounds that bio-accumulate need to be identified.
Since
these five toxaphene congeners represent the long-term chronic toxaphene
exposure problem to humans, the toxicity of these five individual congeners
and/or mixture of these five congeners needs to be determined in more detail
than is currently available in the scientific literature.
46.
The GEC agrees that there should be concern about these five congeners and
more information would be desirable, but the entire PCC mixture is of
concern for long-term chronic exposure. As the OIG noted, the toxicology of
PCC is not well understood. The OIG presents no data in support of ignoring
the other 670-plus compounds in the PCC mixture manufactured by Hercules.
To the contrary, and borne out by discussion of Dr. Olson’s study, short
term exposures can have profound effects on offspring, and the exposure
duration during the study was not long enough to produce effects
attributable to bioaccumulation. Potential endocrine disruption by PCC
compounds or metabolites must remain under consideration as toxic components
of PCC, as well as other potential adverse health effects noted in the ATSDR
Toxicological Profile for Toxaphene. Synergistic effects of the PCC
compound in Glynn County could be much different than those noted in studies
since both PCC and PCC manufacturing wastes are the chemicals of concern.
Dr. Gill’s and Dr. Barr’s studies discussed by the OIG are interesting, but
the OIG failed to note that the source was airborne transport to Canada in
Dr. Gill’s study and the general population in Dr. Barr’s study, and not
exposure to PCC and manufacturing waste products. Sampling of the local
Glynn County population will be needed to confirm any applicability between
the results Dr. Gill and Dr. Barr presented and the far different situation
in Glynn County. By no means should the need for additional studies or
information be used as an excuse not to take action to protect the citizenry
of Glynn County from PCC that is widely distributed.
Superfund’s Remedy requires the Evaluation of Toxic Degradation Products
Since
toxaphene is known to degrade in the environment and these degradation
products are thought to be toxic, EPA must evaluate the groundwater at the
Hercules 009 Landfill site for toxaphene’s degradation products,
specifically, the Hx-Sed and Hp Sed congeners, but also the p26, p50, p40,
p41, and p44 congeners.
47.
The OIG has made sweeping conclusions about which compounds in the PCC
mixture manufactured by Hercules are of toxicological concern, and is making
inappropriate recommendations to limit PCC analysis to a few selected
compounds. The OIG previously stated, “Conducting a detailed and
comprehensive risk assessment for the potential exposure to toxaphene from
the Hercules 009 Landfill site is a complex task that is beyond the scope of
this OIG review.” The sweeping recommendations for limited sampling and
analysis do require a comprehensive health assessment and evaluation of
literature far greater in scope than presented in the OIG Report.
The OIG should clearly recommend that all PCC and PCC degradation products
are analyzed, identified, and reported in samples from the Site.
EPA
Method 8081 Tests for Technical Toxaphene
48. As previously commented upon, the method used at the Hercules 009
Landfill Site was the TTF and Hercules Protocol methods, and the OIG should
identify the methods used as such. The OIG report does a very good job of
describing how and why the TTF and Hercules Protocol methods do not
accurately identify PCC but calling the methods used EPA Method 8081
detracts from the Report. ATSDR has done a very good job of articulating
why the TTF and Hercules Protocol methods are not equivalent to EPA Method
8081, and the OIG report would benefit from taking the same approach. The
difference between Method 8081, and the TTF and Hercules Protocol, and the
very different results the methods produce has been well documented
repeatedly with consistent results.
No
Immediate Human Health Risks at the Hercules 009 Landfill
49. The OIG correctly identifies the analytical method used at the Hercules
009 Landfill Site as inadequate, but fails to note that the analytical
method was used in the decision-making process for the soil removal action,
RD, and RA, which brings into question the protectiveness to human health.
Ongoing exposure to PCC contaminated soil is a very real possibility at the
Site, which will remain a significant uncertainty until sampling and
analysis by a reliable method such a NIMS takes place.
OIG
Technical Conclusions
The
chronic health risk to humans is from exposure to toxaphene’s persistent
degradation products (e.g. p26, p50, p40, p41, and p44) and not the original
technical toxaphene mixture.
50. The risk to human health is from all the 670 plus compounds at the
Site, including all PCC compounds and PCC degradation products. The OIG
noted that, “Conducting a detailed and comprehensive risk assessment for
the potential exposure to toxaphene from the Hercules 009 Landfill site is a
complex task that is beyond the scope of this OIG review.” The OIG
should limit the scope of recommendations to advocating that a reliable and
appropriate analytical method be used that detects all PCC compounds and PCC
degradation compounds. Analysis and evaluation of the resulting data should
be used to produce an ATSDR Health Assessment by a toxicologist familiar
with all potential ramifications to human health and the environment.
The GEC agrees with the OIG in that an analytical method that identifies
PCC compounds and PCC degradation compounds is needed, and NIMS being
inserted into SW-846 is an appropriate recommendation.
The OIG identified the need for further research into carcinogenicity and
embryotoxicity, but the scope of the research should not be limited to only
five congeners. The toxicology of PCC is not well enough understood to
limit the scope of research at this time, and the toxicology of PCC
degradation products is even less understood. Regardless of any
recommendations for further research, measures should be taken to determine
the current human health risks through appropriate testing and the
precautionary principal applied until research results are produced,
reviewed, and published in a recognized peer reviewed scientific journal.
Technical Assistance Report
51. The GEC provides technical assistance to our community through an EPA
Technical Assistance Grant. The OIG Report was reviewed by our technical
advisor, Dr. R. Kevin Pegg. The technical assistance report is the product
of Dr. Pegg and reflects his professional opinion about the OIG Report, and
does not necessarily reflect the views of the GEC Board, members, or other
citizens of Glynn County. Here is the Technical Assistance Report on the
OIG Report:
EPA Toxaphene Testing Method Found Inappropriate
Overview
The Environmental
Protection Agency’s Office of Inspector General recently issued a report
entitled “Appropriate Testing and Timely Reporting Are Needed at the
Hercules 009 Landfill Superfund Site, Brunswick, Georgia” dated September
26, 2005. This document, developed by EPA’s Ombudsman, refutes Region 4
EPA’s methods for analyzing toxaphene at the 009 Superfund Site and the
Terry Creek Disposal Superfund Site, and at other areas around Glynn County,
Georgia. Nearly 15 years of data collected on soil, air, water and
biological samples tested in Brunswick are now in doubt.
Each department in the
United Sates administration has an Inspector General office to provide
oversight for the agency. Several years ago the Glynn Environmental
Coalition formally requested an investigation on items ranging from
toxaphene testing in Glynn County to questions regarding lack of compliance
in the cleanups in Brunswick. This first report mainly investigates the
issue of toxaphene analysis. The Office of Inspector General has concluded
that the methods used by Region 4 have not and could not precisely determine
the form of toxaphene found in Glynn County.
Background
The 009 Superfund Site is
a former road construction borrow pit refilled with waste from pesticide
manufacturing at Hercules Inc. Toxic sludge, off-grade product, and
contaminated soil were deposited into the pit, some of which was below the
water table at least part of the year. Although the Record of Decision—the
legally mandated cleanup goals for the site--stated that all contaminated
soils above 76 parts per million (ppm) would be stabilized in situ
the EPA allowed a much simpler cleanup of merely covering the waste with a
soil/cement mixture using above-ground mixing techniques. At question are
the legalities of changing cleanup plans without seeking community input,
and whether or not the cleanup achieved any of the goals of the original
Record of Decision.
The Terry Creek Disposal
area is a marshy region at the confluence of Terry and Dupree Creeks in
Glynn County that receives industrial runoff from the Hercules plant.
Decades of dumping into the creek system and a series of dredging operations
widely distributed toxaphene within the marshes. The main issue at this site
is if toxaphene is accurately measured in seafood since the area is part of
the local fishery.
In addition to the EPA
regulated sites, “toxaphene-like” substances were found in the soils of
local public schools and other public and private properties. Based on this
Report by the EPA Ombudsman, these “toxaphene-like” materials are toxaphene
congeners subject to EPA regulation. Overall, there is the major question of
whether or not the EPA permitted testing giving false data on toxaphene.
There are many scientific studies showing toxaphene can be measured more
accurately than the techniques used by EPA in Glynn County.
Toxaphene and its
breakdown products are poisons, mutagens, possible cancer agents and they do
bioaccumulate.
Toxaphene
Internationally
recognized scientific studies show there are usually three different types
of toxaphene: technical, weathered and biological. Technical toxaphene is
the type made at the factory and sold worldwide for agricultural pest
control. Technical toxaphene is not one chemical, it is a mixture of about
200 different chemicals produced by adding chlorine to camphene, a chemical
made from tree resin. Different manufacturing processes produce slightly
different mixtures. Although the chlorination of camphene can produce any of
about 600+ different chemicals (called congeners) most technical grades have
about 200 chemical congeners. Weathered toxaphene occurs after toxaphene is
used. Environmental processes such as air drying, sunlight and bacteria
degrade toxaphene. Since each of the more than 200 chemicals in technical
toxaphene breaks down differently, weathered toxaphene varies in the types
of chemicals present. Some chemicals appearing in weathered toxaphene are
not found in the original technical grade of toxaphene, but they are still
some of the 600+ different types of chlorinated camphenes, they are just
produced from technical toxaphene by environmental processes. Biological
toxaphene occurs when plants and animals absorb toxaphene from the
environment. Every bacteria, plant, or animal has a different ability to
absorb toxaphene congeners. Fish tissues have a different set of toxaphene
chemicals from humans. Some toxaphene congeners are found often and in high
concentrations (a process known as bioaccumulation), other congeners rarely
occur in animal tissues. Biological toxaphene is very different from
technical toxaphene, but all of the compounds found in biological toxaphene
are still members of the same set of 600+ congeners found in toxaphene.
Note that Glynn County,
Georgia has a fourth and fifth type of toxaphene. Off-grade product,
material that was not toxic enough to sell, and residue from manufacturing,
were dumped locally both in the 009 landfill and into Terry Creek. This
material was not the same as technical toxaphene, but was still toxic,
mutagenic and potentially carcinogenic. It is only found near the sites of
manufacture, such as Brunswick, Georgia. Off-grade product toxaphene and
manufacturing residue toxaphene will still weather and bioaccumulate, just
like technical toxaphene.
Types of toxaphene
measurements
All of the methods for
analyzing toxaphene use gas chromatography or “GC.” GC separates all 600+
possible toxaphene compounds so that they can be seen and measured. There
are several different measurement methods and technologies.
Total Area Method
This is the basic method
required by the US EPA for chemicals with multiple congeners. It detects
technical, weathered and biological grades of toxaphene, as well as the
off-grade product and manufacturing residue forms. Basically, all of the
possible toxaphene chemicals are detected and added together to quantify
total toxaphene. This method was not used by the EPA in Brunswick, Georgia,
but is used at other EPA sites in the United States and by other governments
and researchers around the world.
Toxaphene
Task Force Method
This method was developed
by EPA Region 4 in Atlanta, Georgia, with Hercules Inc., and the State of
Georgia. While gas chromatography is still used, only a few of the chemicals
specific for technical toxaphene are used in the analysis. Even if other
toxaphene chemical congeners are present, they are ignored. The toxaphene
task force method (referred to as EPA Method 8081) detects technical grade
toxaphene as well as the total area method; however 8081 does not detect all
off-grade products, does not detect some forms of manufacturing residue
toxaphene, and can only detect weathered toxaphene in the first few years
after placing in the environment. The TTF method does not detect toxaphene
after it has been in the environment for several years, and it does not
detect biological toxaphene. The TTF method is apparently used only in Glynn
County Georgia and nowhere else in the world. The method is not recognized
by other governments or by researchers as a useful method because it
under-reports the actual toxaphene concentration.
GC negative ion mass
spectroscopy
This technique, called
the NIMS method, can detect all forms of toxaphene and is a widely respected
method with a high degree of scientific merit regarding the interpretation
of results. It is especially useful for detecting biological forms of
toxaphene accumulation. This is the method favored by the EPA Inspector
General; however, it could be a long time before the methodology is adapted
and approved by the EPA for use in Glynn County.
Discussion
Quoting from page 5 of
the Ombudsman’s report section titled “EPA’s Method Fails to Identify
Toxaphene Breakdown Products in Groundwater”: “… the groundwater
monitoring data collected at the site, using EPA’s method, only identified
the original toxaphene mixture in the groundwater.” Further, same page:
“When the OIG looked at the groundwater monitoring data for evidence of
toxaphene breakdown products, the OIG found some evidence suggesting
toxaphene breakdown products may be in the groundwater surrounding the
Hercules 009 Landfill Site.”
In Appendix A of the
report the OIG shows by example chromatograms and states, in the section
titled “EPA Method 8081 Does Not Identify Toxaphene Degradation
Products”: “…EPA Method 8081 fails to detect toxaphene
degradation products (i.e., “weathered” toxaphene or individual toxaphene
congeners) in environmental samples.” Method 8081 is the method produced
by Region 4 EPA’s Toxaphene Task Force using the subset of toxaphene
congeners.
The Ombudsman report
also notes that EPA is required to monitor toxaphene degradation products.
On page 21 in the section titled “Superfund’s Remedy Requires the
Evaluation of Toxic Degradation Products”: “Therefore, the
Superfund’s MNA [Monitored Natural Attenuation] guidance requires EPA to
anticipate and to test for the presence of potentially toxic degradation
products at hazardous waste sites. Since toxaphene is known to degrade in
the environment and these degradation products are thought to be toxic, EPA
must evaluate the groundwater at the Hercules 009 Landfill site for
toxaphene’s degradation products…”
The Ombudsman report
noted other problems with the conduct of sampling by the EPA in Brunswick.
An addendum to the report discussed potential problems with the cleanup of
environmental samples using sulfur, and a second problem with heat settings
on the instrument. Sulfur can interfere with the analysis, some instrument
temperature settings fail to detect toxaphene. In combination with the
inability of methods used by EPA to quantify weathered toxaphene, the
potential biases of the cleanup and column temperature means that much of
the data used by EPA to design and verify Superfund cleanups are doubtful.
The Report also cites
comprehensive toxicology and body burden studies on toxaphene congeners
conducted at a variety of laboratories. Notable among these is the MATT
study (Investigation into the Monitoring, Analysis and Toxicity of Toxaphene
in Marine Foodstuffs, 2000) describing the bioaccumulation of specific
toxaphene environmental end-products in commercial fish species. EPA Region
4 should have been aware of these studies—it is their responsibility to
follow the scientific literature. Region 4 should have responded to the
growing body of literature regarding toxaphene years ago. In addition to
criticizing toxaphene analysis the OIG report also faults EPA on lack of
timely reporting, failure to make key decisions, and notes unacceptable
modifications to “independent” third-party reviews before release to the
public.
Concluding Remarks
For more than a decade
EPA Region 4 used the toxaphene task force method (EPA Method 8081) in Glynn
County despite research showing the method does not give valid data on
environmental toxaphene. At this point it is not clear if cleanups at the
009 landfill and Terry Creek Outfall meet the legal remediation goals. It is
not clear because EPA has used an unreliable method that cannot measure the
types of toxaphene found in water and soil.
It is fair to say much
of the data on toxaphene occurrence and exposure is “inconclusive” for
samples taken in Brunswick and tested by method 8081. Not all of the
thousands of samples examined so far are in error—obviously many observed
both technical toxaphene and some forms of weathered toxaphene. However,
virtually all of the groundwater and soil samples need retesting to verify
the presence or absence of weathered toxaphene.
EPA is proposing
developing new methods using the NIMS method advocated by the Inspector
General. While there may be some confusion over methods, one thing is
crystal clear: EPA Region 4 should not be the agency to produce and
validate any new toxaphene method. The Atlanta, Georgia EPA office is far
too biased to be trusted with developing toxaphene methods.
Written
by R. Kevin Pegg, Ph.D.; edited by Dr. Mary S. Saunders. Copies of the
newsletter are available from the GEC, at the Glynn County library, or at
www.enviro-issues.net
on the Internet.
[1]
Final Expanded Site
Inspection, Hercules Terry Creek Dredge Spoil Area. January 15, 1997.
[2]
Toxicological Profile for Toxaphene. U.S. Department of Health and Human
Services, Agency for Toxic Substance and Disease Registry. August 1996.
[3]
The Merck Index, 1989.
[4]
Keith A. Maruya, Wakeham, S.G., Analysis of Toxaphene Residues in
Sediment and Fundulus from Terry/Dupree Creek. Skidaway Institute of
Oceanography, University System of Georgia. July 31, 1998.
[5]
Keith A. Maruya. Analysis of Toxaphene Residues in Fin- and Shellfish
from Terry/Dupree Creek, Glynn County, Georgia. Skidaway Institute of
Oceanography, University System of Georgia. June 16, 2000.
[6]
Health Consultation - Terry Creek Dredge Spoils Areas/Hercules Outfall
Brunswick, Glynn County, Georgia. Agency for Toxic Substance and Disease
Registry. December 7, 1999.
[7]
Analytical and Environmental Chemistry of Toxaphene. Pergamon Press.
February 1993.
[8]
Record of Decision, Hercules 009 Landfill Site, Description of Selected
Remedy.
[9]
Record of Decision, Hercules 009 Landfill Site, Performance Standards
for Soils, Page 55, Section 9.0 A.3.a
[10]
Record of Decision, Hercules 009 Landfill Site, Cleanup Goals, Page 18,
Section 6.6.
[11]
Record of Decision, Hercules 009 Landfill Site, Responsiveness Summary,
Page 65, Number 7.
[12]
Feasibility Study, Hercules 009 Landfill Site. Page 6-24, Section 6.5.5.
[13]
55 Fed. Reg. 8774 (1990)
[14]
Letter from Curt Fehn, Chief, South Superfund Management Branch, to
Daniel Parshley, Glynn Environmental Coalition, Inc. May 14, 1998.
[15]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, April 1998.
[16]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, August 1998.
[17]
Feasibility Study, Hercules 009 Landfill Site, Page 8-7, Section 8.2.2.
[18]
Remedial Investigation, Hercules 009 Landfill Site. Plate 3.
[19]
Record of Decision, Hercules 009 Landfill Site, Page 7, Figure 5-1.
[20]
Remedial Investigation, Hercules 009 Landfill Site, Appendix C, Page 6,
Section 4.0.
[21]
Letter from Alan Yarbrough, Remedial Project Manager, South Superfund
Remedial Branch; to Timothy Hassett, Senior Environmental Engineer,
Hercules Incorporated. April 16, 1996.
[22]
Record of Decision, Hercules 009 Landfill Site, Page 27, Section 7.4.
[23]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, Page 2, Number 2.
April 1998.
[24]
Record of Decision, Hercules 009 Landfill Site, Page 53, Section 9.0
A.2.
[25]
Treatability Study, Hercules 009 Landfill Site, Page 2-4, Section 2.3.4.
[27]
Summary Report for Supplemental
Soil Analysis at the 009 Landfill, Brunswick, Georgia. November 26,
1997.
[28]
Letter from Curt Fehn, Chief, South Superfund Management Branch, to
Daniel Parshley, Glynn Environmental Coalition, Inc. May 14, 1998.
[29]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, April 1998.
[30]
Feasibility Study, Hercules 009 Landfill Site, Page 8-7, Section 8.2.2.
[31]
55 Fed. Reg. 8774 (1990)
[32]
Letter from Annie Godfrey, Remedial Project Manager, EPA Region IV; to
Daniel Parshley, Glynn Environmental Coalition, Inc. March 5, 1998.
[33]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, April 1998.
[34]
Letter from Curt Fehn, Chief, South Superfund Management Branch, to
Daniel Parshley, Glynn Environmental Coalition, Inc. May 14, 1998.
[35]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, August 1998.
[36]Feasibility
Study, Hercules 009 Landfill Site, Page 8-7, Section 8.2.2.
[37]
Remedial Investigation, Hercules 009 Landfill Site, Page 6-1, Section
6.1.
[38]
Treatability Study, Hercules 009 Landfill Site, Appendix E, Plates E-1,
E-2, and E-3.
[39]
Treatability Study, Hercules 009 Landfill Site, Appendix E, Plates E-1,
E-2, and E-3.
[40]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, April 1998.
[41]
55 Fed. Reg. 8774 (1990)
[42]
Record of Decision, Hercules 009 Landfill Site, Page 47, Section 8.6.
[43]
Letter from Annie Godfrey, Remedial Project Manager EPA Region IV; to
Daniel Parshley, Glynn Environmental Coalition.
[44]
Treatability Study, Hercules 009 Landfill Site, Appendix E.
[45]
55 Fed. Reg. 8774 (1990)
[46]
40 C.F.R.§ 300.435(b)
[47]
Letter from Curt Fehn, Chief, South Superfund Management Branch, to
Daniel Parshley, Glynn Environmental Coalition, Inc. May 14, 1998.
[48]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, April 1998.
[49]
EPA Superfund Fact Sheet, Hercules 009 Landfill Site, August 1998.
[50]
Feasibility Study, Hercules 009 Landfill Site, Page 8-7, Section 8.2.2.
[51]
Remedial Investigation, Hercules 009 Landfill Site. Plate 3.
[52]
Record of Decision, Hercules 009 Landfill Site, Page 7, Figure 5-1.
[53]
Remedial Investigation, Hercules 009 Landfill Site, Appendix C, Page 6,
Section 4.0.
[54]
Letter from Alan Yarbrough, Remedial Project Manager, South Superfund
Remedial Branch; to Timothy Hassett, Senior Environmental Engineer,
Hercules Incorporated. April 16, 1996.
[55]
Letter from Annie Godfrey, EPA Remedial Project Manager; to Timothy
Hassett, Senior Environmental Engineer, Hercules Incorporated, February
17, 1998.
[56]
Telephone Memorandum to Lavon Revells, US EPA; from Dan Keck, Black &
Veatch Waste Science, Inc. July 27, 1995.
[57]
Telephone Memorandum to Gary Bennett, US EPA Environmental Services
Division; from Kristen Lombard, Black & Veatch Special Projects, Corp.
May 16, 1996.
[58]
Memorandum from Danny Reed, Georgia Environmental Protection Division;
to Dr. Randy Manning, Georgia Environmental Protection Division, October
1, 1996.
[59]
Health Consultation - Terry Creek Dredge Spoils Areas/Hercules Outfall
Brunswick, Glynn County, Georgia. Agency for Toxic Substance and Disease
Registry. December 7, 1999.
[60]
Inter-Office Memorandum, Law Environmental, from Leonard Ledbetter; to
Douglas Keilman and Bruce Hough, October 11, 1991.
[61]
Memorandum - Report of "Toxaphene Task Force". United States
Environmental Protection Agency, Region IV, Environmental Services
Division. June 4, 1993.
[62]
Draft Expanded Site Inspection, Terry Creek Dredge Spoil Area,
Brunswick, Glynn County, Georgia. July 12, 1996.
[63]
Memorandum from Danny Reed, Georgia Environmental Protection Division;
to Dr. Randy Manning, Georgia Environmental Protection Division, October
1, 1996.
[64]
Laboratory Narrative, Atlanta Testing and Engineering, Samples received
March 15, 1996, Undated.
[65]
Public Health Assessment for Terry Creek Dredge Spoil Area Brunswick,
Glynn County, Georgia, Agency for Toxic Substance and Disease Registry.
December 16, 1998.
[66]
Health Consultation - Terry Creek Dredge Spoils Areas/Hercules Outfall
Brunswick, Glynn County, Georgia. Agency for Toxic Substance and Disease
Registry. August 12, 2002.
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