FOURTH FIVE-YEAR REVIEW REPORT
For the
Chemplex Site, Clinton County, Iowa
June 5, 2014
PREPARED BY:
U.S. Environmental Protection Agency
Region 7
Lenexa, Kansas
Approved by:
4-rtfcilia Tapia/pirector
SupcrfumPDiyision
Date:
(/-<, - a/
30285261
Superfund
-------
This page is left blank intentionally.
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
TABLE OF CONTENTS
LIST OF TABLES vi
LIST OF FIGURES vi
LIST OF APPENDICES vii
LIST OF ABBREVIATIONS viii
EXECUTIVE SUMMARY x
FIVE-YEAR REVIEW SUMMARY FORM : xi
1. INTRODUCTION 1-1
2. SITE CHRONOLOGY ., 2-1
3. BACKGROUND 3-1
3.1 Physical Characteristics 3-1
3.2 Land and Resource Use 3-1
3.2.1 Site Geology 3-1
3.2.2 Site Hydrogeology 3-2
3.3 History of Contamination 3-3
3.3.1 Landfill Area 3-4
3.3.2 DAC Storage and Truck Loading Area 3-4
3.3.3 Polishing Basin 3-4
3.3.4 Former Waste Storage Areas ; 3-5
3.3.5 DAC Spill Area .3-5
3.4 Initial Response 3-5
3.4.1 OU 1 3-5
3.4.2 OU 2 3-5
3.5 Basis for Taking Action 3-6
3.5.1 OU 1 3-6
3.5.2 OU 2 3-6
4. REMEDIAL ACTIONS 4-1
4.1 Remedy Selection 4-1
4.1.1 OU 1 4-1
4.1.2 OU 2 ; 4-2
4.2 Remedy Implementation 4-3
4.2.1 OU1 4-3
4.2.1.1 Institutional Controls 4-4
4.2.1.2 Hot-Spot Treatment 4-6
iii
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
TABLE OF CONTENTS
4.2 Remedy Implementation (continued)
4.2.1.3 Water Line Extension 4-6
4.2.1.4 Technical Impracticability Zone 4-6
4.2.1.5 Surface Water and Groundwater Monitoring 4-7
4.2.1.6 Contingency Measures 4-7
4.2.1.7 Shutdown and Decommissioning of Groundwater Extraction
and Treatment System 4-7
4.2.2 OU 2 4-8
4.2.3 Operation and Maintenance (O&M) Costs 4-9
5. PROGRESS SINCE LAST REVIEW 5-1
5.1 Recommendation 1: Resolve Remaining Issues and Implement
Environmental Covenants 5-1
5.2 Recommendation 2: Conduct Groundwater Monitoring in Accordance with
Approved 2008 PME Plan and Contingency Plan 5-2
5.3 Recommendation 3: Construct Expansion to City of Camanche Water Supply
and Connect Downgradient Private Water Well Users 5-2
5.4 Recommendation 4: Test Potential Technologies for Hot-Spot Treatment 5-2
5.5 Summary of Results of Implemented Actions 5-3
6. FIVE-YEAR REVIEW PROCESS 6-1
6.1 Administrative Components 6-1
6.2 Community Involvement 6-L
6.3 Document Review 6-1
6.4 Data Review and Evaluation 6-1
6.4.1 Site O&M 6-1
6.4.2 Extraction and Treatment System Monitoring 6-1
6.4.3 Groundwater and Surface Water Sampling 6-2
6.4.3.1 PCE Concentrations in West Region Groundwater 6-2
6.4.3.2 PCE Concentrations in East Region Groundwater 6-2
6.4.3.3 Concentrations of Other VOCs in Groundwater 6-3
6.4.3.4 VOC Concentrations in Surface Water 6-3
6.4.3.5 VOC Concentrations in Munck Residential Well 6-3
6.4.3.6 VOC Concentrations in Equistar Production Wells 6-3
6.4.3.7 PAH Concentrations ...6-3
6.4.4 Groundwater Level Gauging 6-4
6.4.4.1 Vertical Head Differences 6-4
6.5 Site Inspection and/or Interviews 6-5
iv
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
TABLE OF CONTENTS
7. TECHNICAL ASSESSMENT 7-1
7.1 Question A: Is the remedy functioning as intended by the decision documents 7-1
7.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and
RAOs used at the time of the remedy selection still valid? 7-2
7.3 Question C: Has any other information come to light that could call into question
the protectiveness of the remedy? 7-4
8. ISSUES 8-1
9. .RECOMMENDATIONS AND FOLLOW-UP ACTIONS 9-1
10. PROTECTIVENESS STATEMENT 10-1
11. NEXT REVIEW 11-1
12. REFERENCES 12-1
v
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
LIST OF TABLES
Table 1
Chronology of Site Events
Table 2
Groundwater Cleanup Goals
Table 3
Summary of Sampling Required by the PME Plan and PME Plan Addendum 4
Table 4
Summary of VOCs Detected in Equistar Production Wells -2009 through 2013
Table 5
Wells Downgradient of the Site with Detected Chemical Concentrations Exceeding
Cleanup Goals during 2013 Sampling Events
Table 6
Summary of VOCs Detected in Surface Water - January 2009 through May 2013
Table 7
Summary of PAHs Detected in Groundwater and Surface Water - January 2009 through
May 2013
Table 8
Comparison of VOC Concentrations in Groundwater with Trigger Levels - January 2009
through May 2013
LIST OF FIGURES
Figure 1 Chemplex Site and Vicinity Map
Figure 2 Conceptual Model
Figure 3 OU 2 Site Plan and On-Site Areas of Potential Concern
Figure 4 Environmental Covenants and Ordinance Area Boundaries
Figure 5 Technical Impracticability Zone Boundary
Figure 6 PCE Concentrations (ng/L) Detected in Groundwater Samples from Overburden Through
2013
Figure 7 , PCE Concentrations ([xg/L) Detected in Groundwater Samples from Upper Scotch Grove
Through 2013
Figure 8 PCE Concentrations (j-ig/L) Detected in Groundwater Samples from Lower Scotch Grove
Through 2013
Figure 9 PCE Concentrations (fxg/L) Detected in Groundwater Samples from Farmers Creek
Through 2013
Figure 10 PCE Concentrations (^g/L) Detected in Groundwater Samples from Lower Hopkinton
Through 2013
Figure 11 PCE Concentrations (f.ig/L) Detected in Groundwater Samples from Blanding Through
2013
Figure 12 PCE Concentrations (ng/L) in Surface Water Samples Through 2013
Figure 13a Concentrations of Chemicals Other than PCE Detected Above Cleanup Goals through
2013 - West Region
Figure 13b Concentrations of Chemicals Other than PCE Detected Above Cleanup Goals through
2013 - East Region
Figure 14 Upper Scotch Grove Formation - November 2013 Potentiometric Surface
Figure 15 Lower Scotch Grove Formation - November 2013 Potentiometric Surface
Figure 16 Farmers Creek Unit - November 2013 Potentiometric Surface
Figure 17 Historic Head Difference in West Region Monitoring Well Pair MW-13C/MW-13D
Figure 18 Historic Head Difference in West Region Monitoring Well Pair MW-18C/MW-18F
Figure 19 Historic Head Difference in West Region Monitoring Well Pair MW-26C/MW-26E
Figure 20 Historic Head Difference in West Region Monitoring Well Pair MW-27C/MW-27E
Figure 21 Historic Head Difference in West Region Monitoring Well Pair MW-71-1/MW-71
Figure 22 Historic Head Difference in East Region Monitoring Well Pair MW-64-1/MW-64
vi
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
LIST OF FIGURES (continued)
Figure 23 Historic Head Difference in East Region Monitoring Well Pair MW-65-1/MW-65
Figure 24 Historic Head Difference in East Region Monitoring Well Pair MW-82B/MW-82C
Figure 25 Historic Head Difference in East Region Monitoring Well Pair MW-83B/MW-83C
Figure 26 Historic Head Difference in East Region Monitoring Well Pair MW-84B/MW-84C
Figure 27 Historic Head Difference in East Region Monitoring Well Pair,MW-106A/MW-106C
Figure 28 Historic Head Difference in East Region Monitoring Well Pair MW-109B/MW-109C
Figure 29 Historic Head Difference in West Region Monitoring Well Pair MW-101C/MW-101D
Figure 30 Historic Head Difference in West Region Monitoring Well Pair MW-97C/MW-97D
Figure 31 Historic Head Difference in Adjacent East Region Wells MW-84C/EW-14c
Figure 32 Historic Head Difference in Adjacent East Region Wells MW-85C/EW-15c
Figure 33 Historic Head Difference in Adjacent East Region Wells MW-108C/EW-16c
LIST OF APPENDICES
Appendix A Inspection Checklist
Appendix.B Inspection Photographs
vii
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton', Iowa
LIST OF ABBREVIATIONS
ACC/GCC
ACC Chemical Company and Getty Chemical Company
AOA
Area of Attainment
ARARs
Applicable or Relevant and Appropriate Requirements
BNA
Base-Neutral/Acid
BTEX
Benzene, Toluene, Ethylbenzene, and Xylenes
CD
Consent Decree
CERCLA
Comprehensive Environmental Response, Compensation and Liability Act
COC
Chemical of Concern
DAC
Debutanized Aromatic Compound
DCE
Dichloroethene
DNAPL
Dense Non-aqueous Phase Liquid
EKI
Erler and Kalinowski, Inc.
EPA
U.S. Environmental Protection Agency
Equistar
Equistar Chemicals, LP, current operators of the polyethylene manufacturing
facility. Also may be referred to herein as Lyondell or LyondellBasell
ESD
Explanation of Significant Differences
EW
Extraction Well
IDNR
Iowa Department of Natural Resources
LGE
Landfill Gas Extraction
LNAPL
Light Non-aqueous Phase Liquid
Lyondell
Lyondell or LyondellBasell, current operators of the polyethylene manufacturing
plant. Also may be referred to herein as Equistar
MCL
Maximum Contaminant Level
MW
Monitoring Well
MWH
Montgomery Watson Harza
NAPL
Non-aqueous Phase Liquid \
NCP
National Oil and Hazardous Substances Pollution Contingency Plan
NPDES
National Pollutant Discharge Elimination System
NPL
National Priorities List
O&M
Operation and Maintenance
OU
Operable Unit
PAH
Polynuclear Aromatic Hydrocarbons
PCE
Tetrachloroethene, also called Tetrachloroethylene or Perchloroethylene
PME Plan
Performance Monitoring Evaluation Plan
POC
Point of Compliance
PRP
Potentially Responsible Party
RAO
Remedial Action Objective
RCRA
Resource Conservation and Recovery Act
RD/RA
Remedial Design/Remedial Action
RI/FS
Remedial Investigation and Feasibility Study
ROD
Record of Decision
RPM
Remedial Project Manager
SOW
Statement of Work
SVE
Soil Vapor Extraction
TBCs
To-Be-Considered guidelines
viii
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
LIST OF ABBREVIATIONS
TCE Trichloroethylene or Trichloroethene
TI Waiver Technical Impracticability Waiver
TI Zone Technical Impracticability Zone
j-tg/L micrograms per liter
VOC Volatile Organic Compounds
*i
ix
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
EXECUTIVE SUMMARY
The Chemplex Superfund Site (Site) is a non-National Priorities List (NPL) site located in Clinton
County, Iowa, in portions of Sections 19, 20, 29 and 30 within Township 81 North, Range 6 East. The
former Chemplex facility is situated 1.5 miles northwest of the city of Camanche and 5.5 miles west of
the city of Clinton on the south side of U.S. Highway 30. The former Chemplex facility, currently
operated by Equistar, manufactures high and low density polyethylene from chemical stocks and began
operation in 1968. A number of areas of concern at the Site were identified during previous
investigations. The Site consists of the former Chemplex facility, an adjacent landfill, and surrounding
areas where the contaminants have come to be located.
The remedy selected in the 1989 Record of Decision (ROD) included a groundwater extraction and
treatment system to address the contaminated groundwater, which constitutes Operable Unit 1 (OU 1) of
the Site. At the time of the 1989 ROD, the nature and extent of groundwater contamination had not been
fully defined. The 1991 Explanation of Significant Differences (ESD) expanded the groundwater
extraction and treatment remedy for OU 1 to address all areas of concern. Construction and shakedown
of the groundwater extraction and treatment system for OU 1 was accomplished with the signing of the
Preliminary Closeout Report on September 14,1995. The remedy selected in the 1993 ROD included a
landfill gas extraction system and capping for the landfill area to address contaminated soils and wastes,
which constitutes Operable Unit 2 (OU 2) of the Site. Remedial construction for OU 2 was documented
in a report by ACC Chemical Company and Getty Chemical Company (ACC/GCC) dated December 31,
1998.
In April 2008, a Statement of Additional Work was issued outlining a performance test of a proposed
revised remedy for OU 1 referred to as exposure control. Based on the evaluation of the performance
testing results, in 2012 the U.S. Environmental Protection Agency issued an Amendment to the Record
of Decision (ROD Amendment) which amended the OU 1 groundwater remedy from a groundwater
extraction and treatment type remedy to an exposure control type remedy. The exposure control type
remedy includes westward extension of the city of Camanche water line with connection of designated
residences, expansion of the groundwater monitoring network, localized treatment of tetrachloroethene
(PCE) "hot spots", and institutional controls including environmental covenants and a well control
ordinance by the city of Camanche. The revised remedy also established a Technical Impracticability
Zone, within which certain Applicable or Relevant and Appropriate Requirements (ARARs) are waived.
ARARs are not waived outside of this zone.
The first five-year review was signed on June 9, 1999. The trigger for this fourth five-year review was
the signing of the third Five-Year Review Report on June 5, 2009.
The determination has been made that the OU 1 remedy and OU 2 remedy as selected by the EPA are
protective of both human health and the environment. Because the remedial actions at all OUs are
protective, the Site is protective of human health and the environment.
x
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chempiex Site - Clinton, Iowa
Five-Year Review Summary Form
xi
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
Five-Year Review Summary Form (continued)
Issue: Hot-Spot Treatment Evaluation
Recommendation: ACC/GCC to evaluate results from Fall 2013
hot-spot treatment event and report to EPA. Additional hot-spot
treatment may be implemented in the future based on review and
evaluation of future groundwater monitoring results.
Affect Current
Protectiveness
Affect Future
Protectiveness
Implementing
Party
Oversight
Party
Milestone
Date
No
No
ACC/GCC
EPA
2/15
Sitewide Protectiveness Statement (if applicable)
Protectiveness Determination: Addendum Due Date (if
Protective applicable):
Click here to enter date.
Protectiveness Statement:
"The remedy at OU 1 is protective of human health and the environment in the short
term because human and ecological exposure to Chemicals of Concern (COCs) in
groundwater and surface water above unacceptable levels is being prevented by
institutional controls and expansion of the public water system supply. So long as the
site use does not change and the implemented engineering and institutional controls
are properly maintained, the remedy is predicted to be protective in the long term. The
remedy at OU 2 is protective in the short term because human and ecological exposure
to COCs in soil above unacceptable levels is being prevented through maintaining the
caps and vegetative covers. So long as the site use does not change and the
implemented engineering and institutional controls are properly maintained, the
remedy is predicted to be protective in the long term. Because the remedial actions at
all OUs are protective, the site is protective of human health and the environment.
xii
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
1. INTRODUCTION
The purpose of five-year reviews is to determine whether the remedy at a site is protective of human
health and the environment. The methods, findings, and conclusions of these reviews are documented in
Five-Year Review Reports. Five-Year Review Reports also describe issues identified during the review
and outline recommendations to address these issues. The EPA (also referred to as "the Agency") is
preparing this five-year review pursuant to the ComprehensiverEnvironmental Response, Compensation
and Liability Act (CERCLA), Section 121(c) and the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP). CERCLA Section 121 states:
If the President selects a remedial action that results in any hazardous substances, pollutants, or
contaminants remaining at the site, the President shall review such remedial action no less often
than each five years after the initiation of such remedial action to assure that human health and
the environment are being protected by the remedial action being implemented. In addition, if
upon such review it is the judgment of the President that action is appropriate at such site in
accordance with section [104] or [106], the President shall take or require such action. The
President shall report to the Congress a list of facilities for which such review is required, the
results of all such reviews, and any actions taken as a result of such reviews.
The Agency interpreted this requirement further in the NCP; 40 CFR section 300.430(f)(4)(ii) states
that:
If a remedial action is selected that results in hazardous substances, pollutants, or contaminants
remaining at the site above levels that allow for unlimited use and unrestricted exposure, the lead
agency shall review such action no less often than every five years after the initiation of the
selected remedial action.
Region 7 of the EPA has conducted a five-year review of the remedial actions implemented at the
Chemplex Site in Clinton County, Iowa. This review was conducted from October 2013 through May
2014. This report documents the results of the review.
This is the fourth five-year review for the Site. The triggering action for this review is the signature date
of the third five-year review, which was June 5, 2009. The current five-year review is required because
hazardous substances, pollutants, or contaminants remain on the site above levels that allow for
unlimited use and unrestricted exposure. This five-year review covers both Operable Unit 1 (OU 1) and
Operable Unit 2 (OU 2) of the Site. OU 1 pertains to Site groundwater and OU 2 pertains to Site soil and
waste material. In Site documents, OU 1 and OU 2 are commonly referred to as the "First Operable
Unit" and the "Second Operable Unit."
1-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
C hemp lex Site ^ Clinton, Iowa
2. SITE CHRONOLOGY
A chronology of Site events is provided in Table 1. This chronology extends from 1968, the year the
former Chemplex polyethylene manufacturing facility (hereinafter referred to as the "former Chemplex
facility" or "facility") began operation, to the end of 2013.
2-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
3. BACKGROUND
The Site is a non-NPL site located in Clinton County, Iowa, in portions of Sections 19, 20, 29 and 30
within Township 81 North, Range 6 East. The former Chemplex facility is situated 1.5 miles northwest
of the city of Camanche and 5.5 miles west of the city of Clinton on the south side of U.S. Highway 30
(Figure 1).
ACC Chemical Company and Getty Chemical Company (ACC/GCC) built the original polyethylene
manufacturing facility in the late 1960s and owned and operated it, under the Chemplex name, through
1984. Since that time, the majority of the former Chemplex facility has been owned by a succession of
owners. One exception is the 7-acre landfill area on the west side of the former Chemplex facility and a
portion of the land located southwest of the facility that continues to be owned by ACC/GCC. The
former Chemplex facility is currently owned by Equistar Chemicals, LP, and operated by
LyondellBasell, which continues to manufacture high and low density polyethylene from chemical
stocks. It is still also known under the previous name of Equistar. The names "Equistar," "Lyondell,"
and "LyondellBasell" may be used interchangeably in this report and in other project documents to
identify the current plant operator.
The Site consists of the former Chemplex facility, an adjacent landfill, and surrounding areas where the
contaminants have come to be located.
3.1. Physical Characteristics
Surface topography around the former Chemplex facility generally slopes down to the south, with two
natural streams on the east and west sides of the Site (the Eastern and Western Unnamed Tributaries; see
Figure 1). Both of these streams flow to the south and empty into Rock Creek, approximately 2,500 feet
south of the facility, which in turn flows into the Mississippi River.
3.2. Land and Resource Use
The former Chemplex facility is located northwest of the city of Camanche and west of the city of
Clinton in a predominantly agricultural area between U.S. Highway 30 and 21st Street (also called
Hawkeye Road). The former PCS Nitrogen facility, also known as Hawkeye Chemical and later
Arcadian, is a former fertilizer manufacturing plant located southeast of the former Chemplex facility on
the south side of 21st Street (Figure l)vThe Todtz Farm Superfund site is located approximately one
mile south of the former Chemplex facility. The areas adjacent to and south of the former Chemplex
facility are zoned for industrial use.
3.2.1. Site Geology
The stratigraphic layers of importance at the Site, from the ground surface downward, consist of
(1) unconsolidated sediment (i.e., Overburden); (2) several fractured Silurian-era dolomite rock layers,
and (3) shale of the Ordovician-era Maquoketa Formation.
The Overburden at the Site consists of loess, glacial drift material, and older alluvial sediments. During
the Quaternary age, advancing glaciers eroded most of the alluvial sediments. Loess and glacial drift
3-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
were deposited that consist predominantly of mixed clay and silt with sand and gravel stringers.
Remnants of the alluvial sediments can be found filling ancient stream channels and depressions carved
in the bedrock at the base of the Overburden. The alluvium, consisting of gravel, cobbles, or boulders, is
referred to as the basal sand and gravel. The basal sand and gravel is present mainly in the southwestern
area of the Site. The Overburden ranges in thickness from less than 1 foot along the Western Unnamed
Tributary adjacent to the polyethylene plant to approximately 90 feet in areas south of 21st Street.
The Overburden lies unconformably on a sequence of Silurian-era dolomite bedrock that has been
categorized into three groups of geologic formations: 1) the Scotch Grove Formation, 2) the/Hopkinton
Formation, and 3) the Blanding, Tete des Morts, and Mosalem Formations (Figure 2-1).
Scotch Grove Formation - This formation ranges in thickness from 19 to 140 feet across the Site.
Based on geophysical testing, the Scotch Grove Formation has been differentiated into the Upper
Scotch Grove, which is highly weathered and porous,'and the Lower Scotch Grove, which is
fractured but not weathered.
Hopkinton Formation - This formation lies below the Scotch Grove Formation, is encountered at
depths of approximately 90 to 150 feet below ground surface (bgs), and varies in thickness from 70
to 110 feet. It is composed of the Picture Rock, Farmers Creek, and Lower Hopkinton Members. The
Picture Rock Member is a gray, fine-grained dolomite rock that ranges from 10 to 30 feet thick. The
Picture Rock Member is less permeable than either the overlying Scotch Grove Formation or the
underlying Farmers Creek Member, and therefore is considered to be an aquitard. The Farmers
Creek Member is 15 to 20 feet thick and is extremely porous due to fossil molds and solution
cavities and holes, called vugs. Regionally it is the most consistently groundwater-productive
stratum in the Silurian-era bedrock sequence, although the weathered portions of the Scotch Grove
are generally more productive at the Site. The 40- to 60-feet thick Lower Hopkinton Member is
generally porous and contains cavities.
Blanding, Tete des Morts. and Mosalem Formations - The Blanding Formation underlies the
Hopkinton Formation. The top of the Blanding Formation is located approximately 190 to 250 feet
bgs and is typically 20 to 40 feet thick. It consists of dolomite rock with abundant chert nodules and
seams. Locally, chert may make up as much as 50 percent of the Blanding Formation. The Tete des
Morts and Mosalem Formations lie beneath the Blanding Formation and are encountered at depths of
approximately 200 to 270 feet bgs. Their combined thickness is about 10 feet. Because these
formations are thin and relatively deep, they are typically not differentiated from the Blanding
Formation in illustrations of the conceptual model. Dolomite rock in the Tete des Morts and
Mosalem Formations contains chert nodules and shale seams, and is typically very dense.
The Silurian-era dolomite bedrock sequences discussed above lie unconformably on the Brainard Shale
of the Ordovician-era Maquoketa Formation. The Maquoketa Formation is a massive sequence of shale
that has very low permeability and ranges in thickness from 114 to 275 feet. The massive, dense shales
of the Maquoketa Formation are considered a regional aquiclude.
3.2.2. Site Hvdrogeologv
Groundwater occurs at the Site in both the overburden and the underlying bedrock layers, with the
groundwater potentiometric surface typically situated in the overburden at depths of 1 to 8 feet. In
3-2
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
general, groundwater flows toward the south, with higher gradients in the areas near the Eastern and
Western Unnamed Tributaries. In the vicinity of the tributaries, flow directions tend to be oriented more
toward the west and east, in the direction of the respective tributaries.
Principal flow paths for groundwater in the overburden are the sand and gravel stringers in the loess and
glacial drifts, and the basal sand and gravel in the southwestern area of the Site. Investigations have
demonstrated that groundwater in the overburden exfiltrates into the Eastern and Western Unnamed
Tributaries, with groundwater providing much of the baseflow in these streams during dry periods.
Groundwater in the West Region of the Site generally flows to the southwest, and groundwater in the
East Region flows to the southeast. Groundwater velocity in the overburden has been estimated at 24
feet per year (ft/yr). Groundwater vertical hydraulic gradients within the overburden are upward near the
Western and Eastern Unnamed Tributaries, consistent with the findings that groundwater recharges
these tributaries. Elsewhere at and near the Site, groundwater vertical hydraulic gradients within the
overburden are downward.
The bedrock water-bearing zones are usually confined, with the groundwater potentiometric surface
typically situated within the overburden. The Eastern and Western Unnamed Tributaries also appear to
affect groundwater flow in the shallower bedrock zones. Groundwater flow in the bedrock is skewed to
the south near these tributaries. Groundwater velocity in the bedrock under pre-pumping conditions has
been reported to vary from an estimated 1.5 ft/yr in the Picture Rock layer to 76 ft/yr in the Upper
Scotch Grove layer. Recharge of Silurian-era bedrock in Iowa results primarily from precipitation that
infiltrates through the overburden. Downward groundwater flow through bedrock occurs at the Site
given the average annual rainfall of 36 inches and the existence of naturally-downward vertical
hydraulic gradients between the overburden and bedrock throughout much of the Site plus recharge from
upgradient areas. Even though all formations in the Silurian-era bedrock sequence are hydraulically
interconnected, downward volatile organic compound (VOC) transport via groundwater is inhibited by
the Picture Rock layer, which exhibits lower permeability than the other bedrock strata. Downward
vertical gradients have been measured in the Site's east region. Such gradients are measured in the east
region both across the Picture Rock layer and between the bedrock layers underlying the Picture Rock.
In contrast, vertical gradients in the west region bedrock are near-neutral.
3.3. History of Contamination
Polyethylene wastes from the former Chemplex facility operations were disposed of at several locations
within the facility, resulting in impacts to soil and groundwater. Components of these wastes included
chlorinated hydrocarbons, particularly tetrachloroethene, also called perchloroethylene (PCE); benzene,
toluene, ethylbenzene, and xylenes (collectively referred to as BTEX); and polynuclear aromatic
hydrocarbons (PAHs). Areas of disposal or release, shown on Figure 3, include the following:
3-3
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
• Landfill Area,
• Debutanized Aromatic Compound (DAC) Storage and Truck Loading Area,
• Polishing Basin,
• Former Waste Storage Areas, and
• DAC Spill Area.
A brief description and history of each of these areas is presented below.
3.3.1. Landfill Area
The Landfill Area, which is no longer an active waste disposal area, is located near the west-central
boundary of the fenced portion of the former Chemplex facility and covers approximately seven acres.
The Landfill Area was used for disposal of various wastes generated at the former Chemplex
polyethylene manufacturing facility, including demolition debris and water treatment sludge. From
about 1968 to 1978, PCE was used from time to time at the former Chemplex facility to clear clogged
piping. The spent PCE was disposed of in the Landfill Area.
3.3.2. DAC Storage and Truck Loading Area
The DAC Storage and Truck Loading Area is an active operation area that has been in use since the
inception of facility operations in 1968. DAC is a by-product of the polyethylene production process that
has a high benzene content. The area contains aboveground storage tanks, a transfer pump station, a
truck loading area, and a rail tank car loading area. In the past, this area was not paved or otherwise
protected from surface water infiltration. As a result, infiltration of chemical-containing surface water
led to soil and groundwater impacts at this location. Subsequent paving and soil compaction have
reduced the potential for surface water infiltration.
3.3.3. Polishing Basin
This area is currently used by Equistar as a tertiary process water treatment unit that receives process
water from a biological treatment unit. The Polishing Basin was originally constructed with a clay liner
in 1968 and was historically used as a process water settling pond. In 1974, during dredging of the pond,
the clay liner was damaged, causing contaminants to leach into the underlying soil. In 1982, the
Polishing Basin was drained, revealing the damage to the clay liner from the 1974 dredging.
The Polishing Basin was subsequently rebuilt with a new liner system consisting of compacted clay,
bentonite, and a high-density polyethylene liner. An underlying leachate collection system was also
installed. Shallow groundwater collection systems are located downgradient of the Polishing Basin
consisting of several french drains and collection sumps. Portions of these shallow groundwater
extraction systems, operated by Equistar, were in operation at the end of 2013.
3-4
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
3.3.4. Former Waste Storage Areas
Wastewater treatment plant sludges and polyethylene process wastes were stored in several areas,
including Waste Pile F, Container Storage Area H-2, and Surface Impoundments B, C, and D (see
Figure 3). All of the wastes and sludges from these areas were ultimately excavated and disposed offsite,
with the excavations given vegetative covers and warning signs as precautionary measures.
3.3.5. DAC Spill Area
In 1982, a line from the plant's DAC Storage Tank ruptured, spilling approximately 37,000 gallons of
DAC into the bermed area around the tank. Although most of the spilled material was contained in the
bermed area and recovered, approximately 1,500 gallons escaped through a rainwater drainage pipe.
Approximately 1,000 gallons of the 1,500 gallons that escaped was recovered. The remaining 500
gallons flowed south in a drainage ditch that eventually drained into the Western Unnamed Tributary.
The DAC Spill Area includes the DAC Storage Tank, the bermed area for the tank, and the drainage
ditch adjacent to the bermed area.
3.4. Initial Response
The Site was identified as a potentially uncontrolled hazardous waste site and was proposed for the NPL
on October 15, 1984. In accordance with the Resource Conservation and Recovery Act (RCRA) deferral
policy, in 1991 the Site was removed from the list of sites being proposed for the NPL. The Site is being
addressed as a Superfund Alternative site. Table 1 lists major Site events.
3-4.1. OU 1
Pursuant to Section 106(a) of CERCLA, 42 U.S.C. 9606(a), and Section 3013 of RCRA, as amended, 42
U.S.C. 6934, on September 8,1987, the EPA entered into a Consent Order with several Potentially
Responsible Parties (PRPs), including USI (now Equistar) and ACC/GCC, to investigate the Landfill
Area and the DAC Storage and Truck Loading Area.
This investigation and previous investigations were summarized in the June 1989 Remedial
Investigation and Feasibility Study (RI/FS). With this information and other documents available in the
Administrative Record file, the EPA issued the first Record of Decision (ROD) for the Site on
September 27, 1989.
3.4.2. OU 2
At the time the ROD for OU 1 was issued in 1989, the EPA determined that there was not sufficient
information concerning the nature and extent of soil contamination at the Site to select a remedy for soil
cleanup. Therefore, on December 28, 1989, the EPA entered into an Administrative Order on Consent
with the PRPs to conduct an RI/FS on these soils, designated as OU 2. This Administrative Order on
Consent was issued pursuant to Sections 104(b) and 122(d) of CERCLA, 42 U.S.C. 9604(b) and
9622(d).
3-5
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
The RI/FS for OU 2 was completed in December 1992. The EPA issued a ROD for OU 2 on May 12,
1993.
3.5. Basis for Taking Action
3.5.1. OU 1 '
An assessment of the non-cancer and excess lifetime cancer risks from exposure to contaminated soil
and groundwater was performed in 1989 and presented as an Endangerment Assessment. This risk
characterization formed part of the basis for taking remedial actions that were called for in the
September 27,1989 ROD for OU 1. The OU 1 ROD1 documented that both non-cancer risks and excess
lifetime cancer risks from exposure to the contaminants in the groundwater were above acceptable
thresholds. For worker exposure to surface soils in the DAC Area and for child exposure to surface
water, the non-cancer risks represented a Hazard Index of less than 1, and excess lifetime cancer risks
were in the acceptable risk range. The OU 1 ROD also stated that there did not appear to be an adverse
ecological impact from the Site.
Updated human health and ecological risk assessments were prepared in 2006 as discussed in the
Updated Focused Feasibility Study. Scenarios evaluated as part of the human health risk assessment
included downgradient residents using groundwater for domestic use, child residents wading in Rock
Creek, and downgradient residents exposed to intrusion of vapors from groundwater. The cancer risks
were in the acceptable risk range and the Hazard Index was acceptable (i.e., less than 1) for the scenarios
of child residents wading in Rock Creek and downgradient residents exposed to intrusion of vapors from
groundwater.
Cancer risks and excess lifetime cancer risks for the scenario of downgradient residents using
groundwater for domestic use exceeded acceptable thresholds.
The 2006 ecological risk assessment indicated that there did not appear to be an adverse ecological
impact from the Site, based on comparisons of surface water VOC concentrations with potentially-
applicable water quality criteria.
3.5.2. OU 2
The primary objective for the OU 2 remedial action was to reduce the mass of contaminants potentially
available for release into groundwater. Potential risks from exposure to contaminated soils and wastes
were discussed in the Chemplex OU 2 ROD.
The OU 2 baseline risk assessment2 concluded that there would not be unacceptable non-cancer or
excess lifetime cancer risks posed by exposure to the onsite soils and wastes. Potential non-cancer risks
1 The risk assessment evaluated the following indicator chemicals: antimony, benzene, chloroform, 1,2-dichlorethene,
ethylbenzene, PAHs, styrene, PCE, TCE, and toluene. The OU 1 risk assessment evaluated the following pathways: (a)
inhalation of fugitive dust in the DAC Area by workers, (b) inadvertent ingestion of surface soil in the DAC Area by
workers, (c) dermal contact with surface soil in the DAC area by on-site workers, and (d) dermal contact with surface vyater
in the intermittent tributary to Rock Creek by children.
2 The OU 2 ROD evaluated four receptors: (a) an on-site worker, (b) a trespasser, (c) an off-site receptor, and (d) an on-site
construction worker. COCs were VOCs and PAHs. .
3-6
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
were determined to represent a Hazard Index of less than 1, and the potential cancer risks were
determined to be less than an excess lifetime cancer risk of 10"4 (i.e., risks were within the range that the
EPA typically considers to be acceptable). Existing conditions at the Site were also determined to be
protective of potential ecological receptors.
3-7
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
4. REMEDIAL ACTIONS
4.1. Remedy Selection
4.1.1. OU 1
The selected remedy was groundwater extraction and treatment for the Landfill Area and the DAC
Storage and Truck Loading Area. This ROD was later modified by an Explanation of Significant
Differences (ESD) dated July 26, 1991, to include groundwater extraction and treatment from other
areas of the Site.
Based on the potential risks of exposure to contaminants identified in the on-site groundwater, the focus
of the 1989 ROD was protecting potential groundwater receptors. The ROD, which focused on the
Landfill and DAC Areas, states that:
"The purpose of this operable unit remedial action is to mitigate the movement of the
contaminated groundwater from this site and to permanently treat, destroy and dispose of
contaminants found in these groundwater plumes. Also, this operable unit should protect the
nearby downgradient private drinking water wells from these contaminated plumes prior to
implementation of the final remedial action for this site."
The ESD modified the 1989 ROD to implement a site-wide groundwater remedy that included a point of
compliance (POC) boundary. The remedial objectives were further defined during the RD as follows:
• extract highly-contaminated groundwater within the POC boundary that was not related to
non-aqueous phase liquid (NAPL) source areas to the extent appropriate to expedite completion
of the Remedial Action,
• extract groundwater with the goal that the cleanup standards specified in the OU 1 Consent
Decree (CD) are met in the non-complying areas downgradient of the POC boundary, referred to
as the Areas of Attainment (AOA),
• extract light non-aqueous phase liquid (LNAPL) where feasible and where such recovery would
reduce contaminant migration downgradient of the POC,
• prevent further vertical migration of dense non-aqueous phase liquid (DNAPL) into the bedrock
aquifer,
• prevent further horizontal chemical migration into areas outside the POC boundary,
• lower the groundwater table in areas of source soils to assist the Chemplex OU 2 Remedial
Action, and
• treat extracted groundwater so that effluent concentrations comply with levels specified in the
National Pollutant Discharge Elimination System (NPDES) permit.
4-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowci
As described in Section 4.2.1 of this report, the remedy selected in the ROD was subsequently amended
by the EPA's Amendment to the Record of Decision (ROD Amendment) issued December 26, 2012.
The 2012 ROD Amendment changed the groundwater remedy from groundwater extraction and
treatment to an enhanced exposure control remedy.
The ROD Amendment dated December 2012 modified the remedial action objectives (RAOs) to reflect
current conditions at the Site:
• RAO 1: Prevent human exposure to VOCs in groundwater and accessible surface waters at
levels greater than a cumulative Hazard Index3 of 1.0 for non-carcinogenic risks and a
cumulative incremental lifetime cancer risk4 exceeding the range of 10"4 (one in ten thousand) to
10~6 (one in one million).
• RAO 2: Limit exposure by potential ecological receptors in Rock Creek and downgradient
surface waters to:
o PCE at levels exceeding 98 micrograms per liter (fxg/L);
o Trichloroethene (TCE) at levels exceeding 80 |.ig/L;
o 1,2-Dichloroethene (1,2-DCE) at levels exceeding 590 [xg/L; and
o Vinyl chloride at levels exceeding 930 (ig/L.
• RAO 3: Prevent migration of site-related chemicals of concern (COCs), above the health-based
concentrations described in RAO 1, to those portions of downgradient areas where groundwater
is being used as a potable water supply.
4.1.2. OU 2
The 1993 ROD selected a remedy of capping and construction of a soil vapor extraction (SVE) system
for the Landfill area; establishment of vegetative covers in other designated areas of the former
Chemplex facility; and implementation of institutional controls in the areas of concern. The ROD for
OU 2 addressed contaminated soils and wastes that presented a threat to human health and the
environment from direct exposure or from indirect exposure through migration of contaminants into
groundwater. Together, the OU 1 and OU 2 remedies were intended to address all human health and
environmental risks identified at the Site. The remedial objectives for OU 2 were:
• reduction of carcinogenic risks to on-site workers and construction workers from'direct dermal
and inhalation exposure to soil to a risk level of approximately 10"6 or less, and
1 The Hazard Index is defined as the sum of the "Hazard Quotients", or estimated^ non-carcinogenic risks, for each VOC to
which an individual may be exposed in the form of groundwater or surface water. Each VOC's contribution to the Hazard
Index is the estimated potential dosage divided by the "reference dose" for drinking water exposures and other oral
exposures, or by the "reference concentration", for inhalation exposures.
4 Carcinogenic risks are estimated by multiplying the projected dosage for each VOC by either (1) the Cancer Slope Factor,
for drinking water exposures and other oral exposures, or (2) the Unit Risk Factor, for inhalation exposures.
4-2
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
• reduction of contaminant migration into groundwater to the extent practicable, consistent with
the OU 1 groundwater remedy.
4.2. Remedy Implementation
4.2.1. OU 1
In the OU 1 CD entered into with the United States on November 7, 1991, ACC/GCC agreed to perform
the OU 1 Remedial Design/Remedial Action (RD/RA) and pay past costs. The RD, conducted in
conformance with the 1989 ROD, was approved by the EPA on February 2, 1994.
The original OU 1 remedy as selected in the 1989 ROD, as modified in the 1991 ESD, selected a site-
wide, comprehensive groundwater remedy, and defined groundwater containment and attainment areas.
The remedy included the following components:
• Institutional Controls;
• Groundwater Extraction/Plume Containment;
• NAPL Management;
• Groundwater Treatment and Discharge;
• Construction, Operation, and Maintenance of the Remedy;
• Verification and Monitoring System; and a
• Contingent Technical Impracticability Waiver for the Area of Attainment.
The main component of the remedy was a groundwater extraction and treatment system that began
operating in 1994. The system consisted of 51 extraction wells (EWs) screened at various depths in the
soil overburden and underlying bedrock layers.
While the system was in operation, extracted groundwater was conveyed to the Chemplex groundwater
treatment system in two process streams. One stream, anticipated to contain both PAHs and VOCs, was
labeled the Base-Neutral/Acid (BNA) Stream. The other stream, anticipated to contain only VOCs, was
referred to as the VOC Stream. The BNA and VOC Streams were p'assed through separate air stripping
towers to remove VOCs. The BNA Stream also flowed through aqueous-phase granular activated carbon
to remove PAHs. After treatment, the two streams were combined and discharged to the Mississippi
River through a permitted outfall shared with the neighboring Equistar polyethylene plant.
Equistar continued to operate and maintain the several french drain and wick well remediation systems
located south and southeast of the Polishing Basin. Extracted groundwater was treated within Equistar's
in-plant wastewater treatment system and discharged under the plant's NPDES permit.
Pursuant to the 1991 CD, ACC/GCC implemented this remedy until the EPA issued the ROD
Amendment in December 2012. Operation of the existing groundwater recovery and treatment system
4-3
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
was suspended during the remedy performance test from 2008 to 2012. The 2012 ROD Amendment
modified the remedy in order to more effectively protect human health and the environment in light of
residual VOCs believed to be present in fractured bedrock and the naturally-occurring biological
reductive dehalogenation that has been observed in Site groundwater. The revised remedy includes the
following components:
• Surface water and groundwater sampling and gauging using an expanded monitoring well
network.
• Contingency measures if detected contaminant concentrations exceed certain trigger levels.
• Institutional controls consisting of:
o environmental covenants prohibiting construction of potable water supply wells
screened above the Maquoketa Formation in the area south of the former Chemplex
facility.
o a city of Camanche ordinance that requires connection of new water services to the city
municipal water system in locations where municipal water main connections are
available.
• Shutdown and decommissioning of the existing groundwater extraction and treatment system.
• Localized hot spot treatment with a strong oxidant such as permanganate or with an electron
donor such as vegetable oil or lactose solution as determined in discussions with the EPA as
appropriate based on monitoring data.
• Extension of the city of Camanche municipal water line along 9th Street and 31st Avenue, and
connection of designated residences to this extension.
• Establishment of a Technical Impracticability Zone, within which certain groundwater cleanup
standards, called Applicable or Relevant and Appropriate Requirements (ARARs), are subject to
a technical impracticability waiver (TI Waiver), including selected Maximum Contaminant
Levels (MCLs) for drinking water.
These components are discussed in more detail below. As of the preparation of this Five-Year Review
Report, ACC/GCC and the EPA are negotiating a modification to the 1991 CD to document the revised
remedy approach set forth in the 2012 ROD Amendment. Once signed by all parties, the modification to
the 1991 CD will be filed with the Federal District Court.
4.2.1.1. Institutional Controls
Institutional controls are administrative and legal measures restricting the potential use of chemical-
containing groundwater until cleanup goals are achieved. The Iowa Department of Natural Resources
(IDNR) placed the Site on the Iowa registry of hazardous waste sites. This registry requires placement of
a state notice on the affected deeds preventing land transfer or change in land use without state approval.
Pursuant to the 1991 CD, ACC/GCC, Quantum (now Equistar), and the City of Clinton, who were
owners of properties within the Chemplex site and the AOA at that time, were required to record
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
restrictive covenants and access easements with the County Recorder of Deeds. As discussed in the 2004
Five-Year Review Report, the initial restrictive covenants were recorded by the Clinton County
Recorder's office on August 21, 2001. Those covenants prohibited the construction, maintenance and
use of any wells for drinking water supply or irrigation, with the exception of the existing Equistar
production wells, which are screened below the Maquoketa Formation.
As shown on Figure 4, environmental covenants and a city of Camanche ordinance have been put in
place to implement the land use restriction requirements of the December 2012 ROD Amendment.
These environmental covenants encompass the former Chemplex facility, including the now-inactive
Chemplex Landfill, plus immediately-downgradient areas along the south side of 21st Street. The
following ordinance and environmental covenants have been put in place:
• City of Camanche Public Water Supply Ordinance: On May 5, 2009, the City of Camanche
adopted ordinance number 697 restricting the use of existing water supply wells and prohibiting
construction of new wells within city limits, except for groundwater quality monitoring wells.
• Environmental Covenants: Environmental covenants were established on certain properties,
including most of the Equistar polyethylene plant, the Cross Roads Land Development, LLC
(Cross Roads) property to the southeast that encompasses the former PCS Nitrogen fertilizer
plant, and the Chemplex Landfill and other lands owned by ACC/GCC southwest of the Site.
These covenants were recorded with Clinton County on October 31, 2008 (for ACC/GCC lands
other than the Chemplex Landfill), October 10, 2011 (for the Chemplex Landfill), October 1,
2009 (for the Cross Roads property), and September 26, 2012 (Equistar). The covenants include
the following land use restrictions:
o a prohibition on the construction of groundwater supply wells screened above the
Maquoketa Formation for human consumption, livestock watering, or irrigation of
gardens or agricultural crops except for fiber crops;
o a requirement that all new groundwater wells constructed to depths penetrating the
Maquoketa Formation and screened within the underlying layers must be properly sealed
to the satisfaction of the EPA and IDNR;
o a requirement that written permission be obtained from IDNR, and notice provided to the
EPA, prior to abandoning or removing a groundwater well from the Chemplex
groundwater monitoring network;
o a prohibition on residential land use;
o a prohibition on (1) the extraction of water from dewatering wells or sumps and (2) any
activity that may interfere with monitoring or remedial actions required by the EPA; and
o a requirement that property access be provided to the EPA, IDNR, ACC/GCC and their
authorized representatives to conduct monitoring and other activities required by the EPA
or IDNR to fulfill CD requirements.
4-5
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
Boundaries of the environmental covenants and the city of Camanche well ordinance are shown
on Figure 4.
4.2.1.2. Hot-Spot Treatment
With hot-spot treatment, a strong oxidant such as permanganate, or an electron donor such as vegetable
oil or lactate, is applied to the targeted groundwater area through injection into wells. A pilot test of hot
spot treatment was performed in select wells with application of permanganate or vegetable oil in 2009,
with post-treatment monitoring continuing into 2010. The pilot test indicates that both materials are
effective in mitigating local areas with elevated PCE concentrations in groundwater. A second hot-spot
treatment injection was performed during fall 2013 using sodium lactate in one monitoring well,
permanganate in two monitoring wells, and vegetable oil in one monitoring well. The initial post-
monitoring data was collected in November 2013. Additional post-treatment monitoring will occur
during 2014.- v
Under the revised remedy described in the 2012 ROD Amendment, areas for hot spot treatment are to be
identified on a case-by-case basis after evaluating data from the groundwater monitoring network. The
EPA and ACC/GCC will discuss each year's monitoring data during February or March of each year,
considering concentration trends and the sampling locations within the monitoring network. Whenever
ACC/GCC and the EPA identify an area for hot spot or multiple hot spot treatments, ACC/GCC will
submit a work plan identifying injection locations, the planned oxidant or electron donor, a schedule for
performing the work, and a proposal for follow-up monitoring. ACC/GCC has prepared a draft
document titled "Technical Memorandum: Hot Spot Evaluation Guidelines" which has been reviewed
and accepted by the EPA and IDNR. This plan will be incorporated into the modification to the 1991
CD for OU 1, which the EPA and ACC/GCC are currently negotiating.
4.2.1.3. Water Line Extension
As part of the revised remedy, an extension to the city of Camanche municipal water line was
constructed westward to connect designated residences located potentially downgradient of the Site. The
objective of these connections to the city water system was to reduce the .potential for future PCE
exposure by residents previously using private water supply wells.
This extension was constructed during 2009 and 2010. For properties connecting to the extended
waterline, residential water supply wells were decommissioned in accordance with state procedures.
Under the city of Camanche ordinance number 697, no new water supply wells can be constructed on
these properties as described in Section 4.2.1.1. A total of 20 properties have connected to the expanded
water system, including all identified residences along 31st Avenue, located south (potentially
downgradient) of the contaminated groundwater plumes. The extent of the water line extension is shown
on Figure 5.
4.2.1.4. Technical Impracticability Zone
A component of the revised remedy selected in the 2012 ROD Amendment for OU 1 was the
establishment of a Technical Impracticability Zone (TI Zone), the boundaries of which are illustrated on
Figure 5. Within this TI Zone, chemical-specific ARARs, including MCLs, are subject to a technical
4-6
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
impracticability waiver, or TI waiver. The TI waiver has no effect on chemical-specific ARARs outside
the TI Zone.
The TI Zone replaces the POC Boundary that was established as part of the 1991 ESD for OU 1.
4.2.1.5. Surface Water and Groundwater Monitoring
Pursuant to the 1991 CD for OU 1, ACC/GCC was required to implement a groundwater monitoring
network. ACC/GCC prepared a Performance Monitoring Evaluation Plan (PME Plan) dated November
1993. ACC/GCC modified the PME Plan in October 2008 to update several of the monitoring
requirements in support of the performance testing of the groundwater alternative that would later be
described in the 2012 Updated Focused Feasibility Study. In late 2013, ACC/GCC prepared a draft
updated PME Plan that reflected the revised remedy documented in the 2012 ROD Amendment. The
EPA and IDNR have reviewed the draft PME Plan. ACC/GCC has revised the Plan accordingly, which
will be incorporated into a modification to the 1991 CD for OU 1.
Monitoring currently includes semiannual site-wide gauging of water levels and semiannual sampling of
groundwater and surface water samples collected at designated locations. Sampling locations are
monitored for VOCs, with selected monitoring points also monitored for PAHs. Table 3 summarizes the
monitoring plan under the current PME Plan Addendum No. 4.
4.2.1.6.Contingency Measures
In the event that the remedy selected in the 2012 ROD Amendment fails to perform as anticipated,
contingency measures will be implemented as appropriate to mitigate potential exposure to
contaminated groundwater or surface water. Criteria triggering evaluation of contingency measures,
along with schedules and procedures for implementation, are described in the Contingency Plan. This
Plan was originally prepared in September 2008 by ACC/GCC, who revised it in 2013 (EKI, 2013g).
The EPA and IDNR have reviewed and provided comments on this Plan. ACC/GCC has revised the
Plan accordingly, which will be incorporated into a modification to the 1991 CD for OU 1.
Examples of potential contingency measures include, but are not limited to, increasing monitoring
frequency, construction of new monitoring wells, hot spot treatment, surface stream warning signs or
aeration, additional connections to the city of Camanche water line, and/or vapor sampling at
downgradient residences.
4.2.1.7. Shutdown and Decommissioning of Groundwater Extraction and Treatment
System
The existing groundwater extraction and treatment system was shut down in September 2008 for
performance testing of the revised groundwater remedy, and remains shut down in accordance with the
2012 ROD Amendment. Decommissioning of the system's extraction wells has not been performed to
date.
4-7
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
4.2.2. OU 2
Under the CD for OU 2, entered into on February 6, 1995, ACC/GCC agreed to perform the RD/RA at
the OU 2 Study Areas. The RD, conducted in conformance with the 1993 ROD for OU 2, was approved
by the EPA on December 18, 1996.
The major components of the OU 2 remedy, which were implemented in the areas shown on Figure 3,
include the following:
• groundwater level suppression, SVE, warning signs, and capping in the Chemplex Landfill Area;
• warning signs and capping with stone and concrete at the H-2 Area of the DAC Storage and
Loading Area;
• placement of riprap covers, vegetative covers, and warning signs along 21st Street near the
Equistar Polishing Basin;
• excavation and proper disposal of accumulated sludges, and establishment and maintenance of
vegetative covers and warning signs in the Previous Basin Area, Former Waste Pile F, and
Surface Impoundments B and D;
• institutional controls; and
• five-year reviews.
ACC/GCC commenced and completed construction of these components in April 1997 and January
1998, respectively. The SVE system, also referred to as the Landfill Gas Extraction (LGE) System,
included a blower, 55 vapor extraction wells, and a catalytic oxidizer to treat extracted vapors.
The Statement of Work in the 1995 CD for OU 2 (OU 2 SOW) established two categories of shutdown
criteria for the LGE System:
• Concentration-based criteria, evaluated by comparing the concentrations of Target Compounds
(i.e., BTEXs and PCE) in a given well or well cluster with pre-startup concentrations; and
• A time-based criterion, evaluated by comparing the cumulative time of active extraction at a
given well or group of wells. The time-based criterion was considered to have been met after
four years of cumulative active extraction at each well or well group.
As described in the OU 2 SOW, the LGE System could be shut down upon satisfying either one of the
concentration-based or time-based shutdown criteria. As of April 9, 2003, the four-year time-based
shutdown criterion was approved as having been met at all vapor extraction wells, allowing permanent
shutdown of the LGE System on that date. LNAPL recovery from the LGE wells also ceased. The EPA
completed the Remedial Action Report for OU 2 on August 30, 2005.
4-8
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
As required by the OU 2 CD, ACC/GCC continues to inspect and monitor the OU 2 Study Areas as
follows:
• Landfill Area:
o Annual inspections of the Chemplex Landfill cap and access roads
o Annual inspections of the Landfill surface water management system
o Quarterly inspections of the Landfill fencing and warning signs
• Area H-2:
o Annual inspections of stone and concrete cap
o Annual inspections of warning sign
• Previous Basin. Former Waste Pile F. and Surface Impoundments B and D:
o Annual inspections of vegetative cover, with replanting of specific bare spots
o Annual inspections of warning signs
• Areas Adjacent to Polishing Basin:
o Annual inspections of riprap and vegetative cover
o Annual inspections of warning signs
As outlined in the OU 2 CD, these inspections and necessary repairs will continue until the inspection
period of thirty years is completed.
4.2.3. Operation and Maintenance (0&M1 Costs
During 2013, the total OU 1 and OU 2 O&M cost, including monitoring, is anticipated to total
approximately $680,000, not including costs for hot spot treatment which are considered to be non-
routine outlays. The ROD Amendment anticipated O&M costs of $19.7 million over 30 years, for an
average annual cost of $660,000. Costs in 2013 included consulting work associated with the
development of work plans associated with both the 2012 ROD Amendment and the modification to the
1991 CD (currently being negotiated). For this reason, it is anticipated that project costs will decrease in
future years, once the modification to the 1991 CD is finalized and lodged by the Department of Justice,
which is expected to occur in 2014.
4-9
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
5. PROGRESS SINCE LAST REVIEW
The previous (2009) Five-Year Review report (EPA, 2009) concluded the following:
• The OU-1 remedy currently protects human health and the environment. There are no human
receptors of drinking water identified as having consumed concentrations of chemicals of
concern from the Site above standards based on drinking water standards developed under the
Safe Drinking Water Act. Existing Site conditions are also considered safe for ecological
receptors. However, in order for the remedy to be protective in the long term, actions need to be
taken to ensure protectiveness. Specifically, the performance test required by the Additional
Work provision of the CD including implementation of environmental covenants, groundwater
monitoring with contingencies, expansion of the Camanche water supply system, and hot spot
treatment of the most highly contaminated groundwater must be completed to ensure that
groundwater contamination does not adversely affect downgradient receptors. After completion
of the performance test, the EPA will evaluate whether further remedial actions are needed; and
• The OU-2 remedy is protective of human health and the environment.
Because the remedial actions at all OUs are currently protective, this Site is currently protective of
human health and the environment. However, additional actions need to be taken to ensure long-term
protectiveness of the Site, as described above. To ensure long-term protectiveness, the report listed four
recommendations:
(1) ACC/GCC, the EPA, IDNR, and relevant property owners need to work to resolve remaining
issues related to establishing environmental covenants.
(2) ACC/GCC needs to conduct groundwater monitoring according to the approved 2008 PME Plan
and Contingency Plan with EPA oversight.
(3) The city of Camanche and ACC/GCC need to construct an expansion of the Camanche public
water supply and hook up downgradient receptors.
(4) ACC/GCC must test potential technologies for groundwater hot spot treatment.
The implementation status of these four recommendations is updated below.
5.1. Recommendation 1: Resolve Remaining Issues and Implement Environmental Covenants
As part of the revised remedy documented in the 2012 ROD Amendment, the use restrictions discussed
in the previous (2009) Five Year Review report were implemented as described in Section 4.2.1.1:
• City of Camanche Public Water Supply Ordinance: On May 5, 2009, the city of Camanche
adopted ordinance number 697, restricting the use of existing water supply wells and prohibiting
construction of new wells within designated portions of the city, except for groundwater quality
monitoring wells. Boundaries for the ordinance are shown on Figure 4.
5-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
• Environmental Covenants: Environmental covenants were established for the Chemplex facilty.
and certain downgradient properties, including the Equistar polyethylene plant, the Cross Roads
property which encompasses the former PCS Nitrogen fertilizer plant, and the Chemplex Landfill
and other lands owned by ACC/GCC. These environmental covenants were recorded with Clinton
County for the following areas:
o ACC/GCC property, other than the Chemplex Landfill: October 31, 2008
o Former Chemplex Landfill: October 10, 2011
o Cross Roads property: October 1, 2009
o Equistar property: September 26, 2012
Boundaries for the environmental covenants are shown on Figure 4. Note that the area of the
covenant for the former Chemplex Landfill is not differentiated from the area covered by the
ACC/GCC covenant.
5.2. Recommendation 2: Conduct Groundwater Monitoring in Accordance with Approved
2008 PME Plan and Contingency Plan
Groundwater monitoring was conducted as described in the 2008 PME Plan and subsequent PME Plan
Addenda. Groundwater monitoring results are documented in the quarterly progress reports and the
semiannual monitoring reports. Ongoing monitoring included periodic groundwater level monitoring
and groundwater and surface water quality sampling and analysis at frequencies specified in the 2008
PME Plan. The results from these monitoring events are discussed in Section 6.4.3.
Results from this ongoing monitoring were compared with the trigger levels described in the 2013
Contingency Plan. During the period since the last five-year review, from 2009 through 2013, none of
the trigger levels was exceeded in any groundwater or surface water samples.
5.3. Recommendation 3: Construct Expansion to City of Camanche Water Supply and
Connect Downgradient Private Water Well Users
During 2009 and 2010, the extension of the city of Camanche municipal water system was constructed
to serve designated residences located south of the Site. Construction of this waterline extension,
including erection of two new 250,000-gallon capacity water tanks, was funded by ACC/GCC. A total
of 20 properties were connected to the expanded water system, and the existing private wells at these
properties were decommissioned. The extent of the pipeline extension is shown on Figure 5.
As described in the previous five-year review, the goal of this waterline extension was to limit the risk
of potential future residential exposure to groundwater containing COCs. These potentially
downgradient properties had been using private wells for their water supply, thereby creating a potential
path for human exposure to Site COCs in the future.
5.4. Recommendation 4: Test Potential Technologies for Hot Spot Treatment
Both permanganate, a strong oxidant, and an emulsified vegetable oil solution, serving as a
supplemental electron donor, were tested during a field-scale hot spot treatment pilot study conducted by
ACC/GCC in 2009. Both treatment agents were found to be effective for reducing locally-elevated PCE
5-2
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
concentrations. Field activities were summarized in a 2009 report prepared by Montgomery Watson
Harza (MWH) titled "Hot Spot Pilot Test Field Activities Summary". Subsequent evaluation reports
included the "Hot Spot Pilot Test 6-Month Progress Report" dated May 5, 2010, and the "Hot Spot Pilot
Test Evaluation Report" dated December 2010. A second hot spot treatment event was implemented in
the Fall of 2013.
The Fall 2013 groundwater monitoring event conducted in November 2013 indicated contaminant
concentrations were reduced in the monitoring wells where the hot spot treatment was conducted. The
performance of the hot spot treatment will continue to be monitored in 2014.
5.5. Summary of Results of Implemented Actions
The actions performed to address Recommendations 1 through 4 from the 2009 Five-Year Review have
been implemented and achieved their intended purpose.
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
6. FIVE-YEAR REVIEW PROCESS
6.1. Administrative Components
The current five-year review was conducted by Brian Zurbuchen of EPA Region 7, Remedial Project
Manager (RPM) for the Chemplex site. Other members of the EPA Region 7 staff who contributed to
this review include Nancy Swyers (former RPM for the Site), David Hoefer of the Office of Regional
Counsel, Bill Pedicino, Greg McCabe, and Catherine Wooster-Brown of the Data Integration and
Support Branch, and Ben Washburn of the Office of Public Affairs. Cal Lundberg of the IDNR assisted
in the review as the representative of the state of Iowa.
6.2. Community Involvement
On February 19, 2014, a display ad was placed in the Clinton Herald that a five-year review was to be
conducted. This notice provided information on how to contact the EPA to provide input. The ad
encourages community members to ask questions and report any concerns about the site. As of March
19, 2014, no inquiries have been received with regard to this five-year review.
Soon after approval of this fourth Five-Year Review Report, a notice will be placed in the same
newspaper announcing that the report is complete, and that it is available to the public at the Camanche
Public Library in Camanche, Iowa and at the EPA, Region 7 office.
6.3. Document Review
This five-year review included a review of relevant documents such as quarterly progress reports and
semiannual monitoring reports submitted by ACC/GCC since the Third Five-Year Review Report dated
June 2009. Other documents that were reviewed include (a) reports related to the hot spot pilot test, and
(b) other documents pertinent to the amended remedy, such as the Updated Focused Feasibility Study,
the Proposed Plan, and the ROD Amendment.
6.4. Data Review and Evaluation
6.4.1. Site O&M
As required by the OU 1 CD and the Amended OU 1 CD, MWH on behalf of ACC/GCC has been
performing O&M. This work includes preparing monthly operating reports and a quarterly compendium
of NPDES monitoring results. These monthly and quarterly operating reports are included within the
routine quarterly reports submitted to the EPA and IDNR. ,
6.4.2. Extraction and Treatment System Monitoring
The existing groundwater extraction and treatment system was shut down September 2008. Although the
groundwater extraction and treatment system has not been operating since, ACC/GCC has kept the
NPDES permit active. IDNR issued the first NPDES permit on June 20, 1994, with renewals authorized
by the state of Iowa in June 1999 and September 2008. ACC/GCC has regularly submitted NPDES
renewal applications at the appropriate times. IDNR's permitting group has not always been able to
6-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
respond in a timely manner due to staffing resources; however, in these cases, IDNR has indicated that
the existing permit remains active pending review of the new permit application. ACC/GCC applied to
again renew the NPDES permit in February 2013. NPDES reports continue to be sent to IDNR quarterly
in accordance with the existing NPDES permit.
6.4.3. Groundwater and Surface Water Sampling
ACC/GCC was required to perform groundwater and surface water sampling in accordance with the
PME Plan approved in October 2008 and associated addenda, the most recent of which is Addendum 4
dated March 2013. Table 3 summarizes the PME Plan and Addendum 4 requirements. A revised PME
Plan was prepared in late 2013 and will address sampling requirements for 2014 and future years.
ACC/GCC currently monitors for VOCs in designated extraction and monitoring wells twice annually,
as well as at designated surface water sampling locations. Table 5 compiles water quality sampling
results from wells south of 21st Street (Hawkeye Rd) and downgradient of the former Chemplex facility
that had analyte concentrations exceeding cleanup standards during the 2013 monitoring events.
Figures 6 through 11 depict the locations of monitoring and former extraction wells sampled during
2013. These figures have data boxes compiling historical concentrations of PCE, the primary COC at the
Chemplex site. The six figures show results from wells screened in the Overburden, Upper Scotch
Grove, Lower Scotch Grove, Farmers Creek, Lower Hopkinton, and Blanding water-bearing zones.
As indicated in Table 5, VOC concentrations in 17 downgradient monitoring wells were above cleanup
goals during 2013. All 17 wells are located within the TI Zone (Figure 5), where cleanup goals and other
ARARs have been waived as described in the ROD Amendment. These wells are discussed below. This
discussion divides the Chemplex site and downgradient areas into a "West Region" and an "East
Region" as shown on Figures 6 through 11.
During the 2009 to 2013 period, groundwater concentrations did not exceed any of the levels that would
trigger contingency actions under the Contingency Plan (Table 8).
6.4.3.1. PCE Concentrations in West Region Groundwater
In the West Region, ten wells located in the area south of 21st Street / Hawkeye Road and downgradient
of the former Chemplex facility were found to have contained PCE concentrations that exceeded
cleanup standards in May and/or November 2013. All of these wells are located within the bounds of the
TI Zone.
6.4.3.2. PCE Concentrations in East Region Groundwater
In the East Region, seven wells located in the area south of 21st Street / Hawkeye Road and
downgradient of the former Chemplex facility were found to have PCE concentrations that exceeded
cleanup standards in May and/or November 2013. All of these wells are located within the bounds of the
TI Zone.
6-2
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
6.4.3.3. Concentrations of Other VOCs in Groundwater
As indicated in Table 5 and on Figures 13a and 13b, November 2013 concentrations of TCE,
cis-l,2-DCE, 1,1-DCE, and vinyl chloride each exceeded cleanup standards in at least one of the
downgradient groundwater wells. TCE, cis-l,2-DCE, and vinyl chloride are biodegradation breakdown
products from the microbial reductive dechlorination of PCE. Groundwater trends of PCE breakdown
products tend to mirror PCE concentration trends.
6.4.3.4. VOC Concentrations in Surface Water
Table 6 and Figure 12 summarize surface water sampling results from 2009 through 2013. As noted in
Table 6, PCE and cis-l,2-DCE, along with low concentrations of TCE, trans-l,2-DCE, benzene,
1,1-DCE, and vinyl chloride, have been detected at location SW-1, which is the Western Unnamed
Tributary at its crossing under 21st Street. Increases in VOC concentrations have been noted at SW-1
since 2008, although measurements remain well below surface water trigger levels.
Trace concentrations of cis-l,2-DCE and PCE, below the laboratory reporting limit of 0.5 [xg/L, have
been detected at location SW-2, which is the Eastern Unnamed Tributary at its crossing under
21st Street. Low concentrations of PCE, cis-l,2-DCE, benzene, and TCE have been detected at location
SW-3, in Rock Creek just downstream of its confluence with the Western Unnamed Tributary. Only
sporadic detections of VOCs have been detected at location SW-4, in Rock Creek just downstream of its
confluence with the Eastern Unnamed Tributary.
All concentrations were well below trigger levels for contingency actions under the Contingency Plan
(Table 6).
6.4.3.5. VOC Concentrations in Munck Residential Well
ACC/GCC has sampled the Munck residential well on a voluntary basis (see Figure 1). From 2009
through 2013, no VOCs were detected, with the exception of trace detections of methylene chloride
(also known as dichloromethane), which is a common laboratory contaminant that has frequently been
detected in trip blanks.
6.4.3.6. VOC Concentrations in Equistar Production Wells
ACC/GCC samples four of the Equistar production wells every two years. Table 4 summarizes these
results. No valid VOC detections were reported in any of the Equistar production wells during sampling
events in 2009, 2011, and 2013.
6.4.3.7. PAH Concentrations
Table 7 compiles PAH concentrations detected from 2009 through 2013 in groundwater and surface
water samples. PAHs were not found above cleanup levels in any sample and in general have been
detected only sporadically in groundwater and only at low levels in surface water. PAH sampling
required by the PME Plans and associated addenda is now limited to surface water location SW-1
(annually) and to the four designated Equistar production wells (biennially). When the Munck
residential well is sampled, PAHs are also analyzed in that sample.
6-3
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
6.4.4. Groundwater Level Gauging
As specified in the PME Plans, water-level gauging is conducted to evaluate the groundwater
potentiometric surface, lateral gradients and flow directions, and local vertical head differences between
stratigraphic units. Gauging events are currently semiannual, in the second and fourth quarters; location
and frequency is reviewed during data review meetings with the EPA. The routine monitoring reports
prepared by ACC/GCC summarize these gauging events, including potentiometric surface contour maps
for the Upper Scotch Grove, the Lower Scotch Grove, and the Farmers Creek layers. Figures 14 through
16 show the potentiometric groundwater surface contours from the gauging event in November 2013.
The potentiometric surface contours are interpolated from the field groundwater level data coupled with
groundwater flow simulation results from the Chemplex three-dimensional groundwater flow model and
contouring using the Surfer program.
Following the September 2008 shutdown of the groundwater extraction system, water level gauging has
continued. In general, the piezometric surface has smoothed since 2008, due to the surface no longer
being locally deformed by the cones of depression induced about the extraction wells of the groundwater
extraction system.
6.4.4.1. Vertical Head Differences
Figures 17 through 28 present vertical head differences across the relatively low-permeability Picture
Rock layer for selected monitoring well pairs. These pairs were originally designated in the 1993 PME
Plan for evaluating the potential for mobilizing possible residual DNAPL during recovery system
startup. -
As shown on Figures 17 through 21, vertical head differences across the Picture Rock in the West
Region remained close to neutral under pre-pumping, pumping, and post-pumping conditions at
monitoring well (MW)-13^ MW-27, and MW-71 well pairs. At MW-18, the pumping increased the
upward gradient a near neutral gradient during the pre- and post-pumping conditions. At MW-26, the
pumping appears to have slightly reduced the small upward gradient observed during the pre- and post-
pumping conditions.
Figures 22 through 28 indicate that under pre- and post-pumping conditions there are strong, naturally
downward head gradients across the Picture Rock in portions of the Site's East Region. Downward head
differences have been present during groundwater extraction, persisting, although at a lower magnitude,
after extraction from the Farmers Creek bedrock layer was suspended in 2005. Head differences in the
East Region have continued to be downward after the September 2008 groundwater extraction system
shutdown.
ACC/GCC also monitors vertical head differences between the Farmers Creek layer and the underlying
Lower Hopkinton layer. Figures 29 and 30 show vertical head difference graphs for two Farmers
Creek/Lower Hopkinton well pairs in the West Region, while Figures 31 through 33 illustrate vertical
head differences for three adjacent Farmers Creek/Lower Hopkinton well pairs in the East Region.
6-4
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
As shown on Figures 29 through 33, post-shutdown vertical head differences between the Farmers
Creek and the Lower Hopkinton formations in the West and East Regions remained close to neutral
under pre-pumping, pumping, and post-pumping conditions. Note that for those well pairs where an
extraction well was one of the wells monitored, the assessment above is only appropriate for times at
which the extraction well was not operating. For example, there is an extremely high downward gradient
observed when EW-14c is operating. However, outside of the times the EW-14c itself is operating, the
vertical head differences between the Farmers Creek Member and the Lower Hopkinton Formation is
close to neutral during pre- and post-pumping conditions, as well as under pumping conditions when
other extraction wells are operating.
6.5. Site Inspection and/or Interviews
Nancy Swyers, the EPA's former RPM for the Chemplex site through March 2014, inspected the Site on
November 13, 2013. Participating in the inspection were John Hintermeister (MWH's local operations
subcontractor, former treatment plant Chief Operator) and Melodie Carr of Equistar. A checklist from
the 2001 Five-Year Review guidance was consulted. This completed checklist is included as Appendix
A. A photographic log of pictures taken during the inspection is furnished as Appendix B.
The purpose of the inspection was to obtain on-site information pertinent to the Five-Year Review
assessment of remedy protectiveness. The inspection encompassed the former Chemplex Landfill and
other OU 2 Study Areas and the Groundwater Treatment Building. Inspection of the OU 2 Study Areas
within the Equistar plant was facilitated by Melodie Carr.
The inspection also included a tour of the completed extension of the Camanche municipal water system
and hew water towers. This portion of the inspection was facilitated by Tom Roth and Dave Rickertsen
of the city of Camanche. The city of Camanche indicated that construction of the municipal water
system extension and storage tanks went well, and that the system operates properly. No major issues
have recently been raised by connected residents.
The conclusion of the inspection is that the OU 2 Study Areas and the now-inactive Treatment Building
are well-maintained and secured. Treatment plant records were readily available and up to date. The
extension of the city of Camanche water system is operating properly. No land use changes have
occurred either within the Site or adjacent to the Site since the last Five-Year Review.
6-5
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
7. TECHNICAL ASSESSMENT
This technical assessment addresses the three questions laid out in the EPA's July 2001 Comprehensive
Five-Year Review Guidance to assess remedy protectiveness. For this technical assessment, the
Decision Documents are considered to be the 2012 ROD Amendment for OU 1 and the 1993 ROD for
OU 2. (
7.1. Question A: Is the Remedy Functioning as Intended by the Decision Documents?
Yes. As described below, the remedy is functioning as intended by the Decision Documents.
The review of site documents, ARARs, risk assumptions and the results of site inspections indicate that
the remedy is functioning as intended by the Decision Documents in the following ways:
• The remedy is meeting RAO 1 of preventing human exposure to VOCs in groundwater and
accessible surface waters at levels greater than a cumulative Hazard Index of 1.0 for non-
carcinogenic risks and a cumulative incremental lifetime cancer risk exceeding the range of 10"4
to 10"6. To date, VOC concentrations in downgradient groundwater and accessible surface water
have been below the trigger levels that would warrant actions under the 2013 Contingency Plan.
• The remedy is meeting RAO 2 of limiting exposure by potential ecological receptors in Rock
Creek and downgradient surface waters to PCE at levels exceeding 98 [xg/L, TCE at levels
exceeding 80 fxg/L, 1,2-DCE at levels exceeding 590 (.ig/L, and vinyl chloride at levels
exceeding 930 (.tg/L. To date, surface water concentrations of these analytes have been well
below these trigger levels (Table 6).
• The remedy is meeting RAO 3 of preventing migration of site-related COCs, above the health-
based concentrations described in RAO 1, to those portions of downgradient areas where
groundwater is being used as a potable water supply. To date, VOC concentrations in
groundwater wells have been below trigger levels set forth in the 2013 Contingency Plan.
• The institutional controls required by the ROD and ROD Amendment have been implemented to
help prevent exposure to impacted groundwater and surface water.
• The westward extension of the Camanche municipal water system and the removal of private
water wells at potentially-downgradient residences have provided protection against human
exposure to groundwater containing COCs.
• Hot spot treatment of locally-elevated PCE concentrations was found to be successful during the
2009 pilot test. A second round of hot spot treatment was performed on selected wells during the
Fall of 2013. The initial results of the November 2013 Fall groundwater sampling event indicate
a reduction in COCs. Performance monitoring of the hot spot treatment will continue.
• The annual inspections of the OU 2 Study Areas performed by ACC/GCC have been effective in
maintaining the integrity of the caps and vegetative covers implemented under the OU 2
remedial action.
7-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
ACC/GCC continues to monitor the status of the groundwater plumes and continues to submit
groundwater sampling reports and progress reports to the EPA. Ongoing groundwater and surface
monitoring will document that human health and the environment continue to be protected by the
remedy.
7.2. Question B - Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used
at the time of the remedy selection still valid?
Changes in Standards and To-Be-Considered Guidelines (TBCs)
¦ Have there been changes to risk-based cleanup levels or standards identified as Applicable or
Relevant and Appropriate Requirements (ARARs) in the ROD that call into question the
protectiveness of the remedy?
o Table 2 of this Five Year Review report contains the groundwater cleanup levels that
were revised at the time of the December 2012 ROD Amendment. These revised cleanup
levels generally meet the EPA's health-based screening levels for tapwater at the 1 x 10"6
potential excess cancer risk level, or a hazard index equal to 1 for non-carcinogens. The
exception to this is naphthalene. The 1 x 10° potential excess cancer risk level of 1.4 [ig/l
is the cleanup level for naphthalene used for this Site because there have been
downgradient detections of naphthalene that are believed to not be attributed to the Site
(see footnote f of Table 2). The 1 x 10"5 potential excess cancer risk is still within the
acceptable risk range of 1 x 10"4 to 1 x 10"6. The EPA's Regional Screening Values can
be found at the following web address: http://www.epa.gov/reg3hwmd/risk/human/rb-
concentrationtable/index.html.
o Table 8 of this Five Year Review report compares concentrations of COCs with trigger
levels established in the Contingency Plan. During the 2009 to 2013 period, groundwater
concentrations did not exceed any levels that would trigger contingency actions under the
Contingency Plan. Higher concentrations of COC are detected in the upgradient areas of
the Site but the plume concentrations remain stable. Continued groundwater and surface
water monitoring as well as hot spot treatment to address elevated groundwater
concentrations in the plume will continue to ensure that the remedy remains protective.
o The surface water trigger levels (see below) for the contaminants of concern (COCs)
proposed in the Final Chemplex Feasibility Study (FS) (2007) are still appropriate:
TCE—80 jig/L
PCE—98 ng/L
cis-l,2-DCE—590 |ag/L
vinyl chloride—25 jxg/L
¦ Are there newly promulgated standards that call into question the protectiveness of the remedy ?
o We are not aware of any newly promulgated standards that call into question the
t protectiveness of the remedy.
7-2
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
¦ Have TBCs used in selecting cleanup levels at the site changed in a way that could affect the
protectiveness of the remedy?
o We are not aware of the use of TBCs in selecting cleanup levels for the Site.
Changes in Exposure Pathways
¦ Has land use or expected land use on or near the Site changed (e.g., industrial to residential,
commercial to residential)?
o We are not aware of any land use changes or potential land use changes at the Site.
¦ Have any human health or ecological routes of exposure or receptors changed or been newly
identified (e.g., dermal contact where none previously existed, new populations or species
identified on site or near the site) that could affect the protectiveness of the remedy?
o The human health risk assessor commented on the potential impact of the vapor intrusion
pathway at the Panther Logistics building. The Five Year Review team members
reviewed and evaluated the data near the building. The building is located near
overburden MW-107A. The groundwater concentrations of PCE in that well have been
less than 2 ^g/1. Based on the low concentrations of PCE in that well, the team decided
that the groundwater concentrations in that area are not high enough to be of concern for
the vapor intrusion pathway.
o We are not aware of any changed or new ecological routes of exposure.
¦ Are there newly identified contaminants or contaminant sources?
o We are not aware of any newly identified contaminants or contaminant sources. Recent
data do not show any new contaminants or contaminant sources.
¦ Are there unanticipated toxic byproducts of the remedy not previously addressed by the decision
documents (e.g., byproducts not evaluated at the time of remedy selection)?
o We are not aware of any unanticipated toxic byproducts.
o In accordance with the 2012 PME Plan, a surface water sample was collected at SW-1
and analyzed for Polycyclic Aromatic Hydrocarbons (PAHs). Results were below surface
water ecological screening levels.
¦ Have physical site conditions (e.g., changes in anticipated direction or rate of groundwater flow)
or the understanding of these conditions (e.g., changes in anticipated direction or rate of
groundwater flow) changed in a way that could affect the protectiveness of the remedy?
o No, we are not aware of any changed physical site conditions that affect the remedy. The
OU1 and OU2 RODs concluded that groundwater suppression; capping; a SVE system
7-3
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
for the landfill area; establishment of vegetative covers in other areas of the site; and
institutional controls in all areas would remove/reduce/cover COCs in the soils and the
groundwater. These systems are in place and as long as they are maintained regularly, the
physical site conditions should remain protective.
Changes in Toxicity and Other Contaminant Characteristics
¦ Have toxicity factors for contaminants of concern at the site changed in a way that could affect
the protectiveness of the remedy?
o Table 5 of the December, 2012 ROD Amendment contains the revised cleanup levels,
which are based on the latest toxicity information available to the EPA. With the
exception of naphthalene (see comment above), these revised cleanup levels generally
meet the EPA's health-based screening levels for tapwater at the 1 x 10"6 potential excess
cancer risk level, or a hazard index equal to one for non-carcinogens.
¦ Have other contaminant characteristics changed in a way that could affect protectiveness of the
remedy?
o We are not aware of any other changes to contaminant characteristics that could impact
the protectiveness of the remedy.
Changes in Risk Assessment Methods
¦ Have standardized risk assessment methodologies changed in a way that could affect the
protectiveness of the remedy?
o The EPA has significantly revised several of its risk assessment methodologies since the
signing of the original ROD in 1989. However, these revisions generally do not impact
the protectiveness of the remedy.
7.3. Question C - Has any other information come to light that could call into question the
protectiveness of the remedy?
¦ Are there impacts from natural disasters (e.g., a 100-year flood)?
o We are not aware of any natural disasters that have occurred on this Site.
¦ Has any other information come to light which could affect the protectiveness of the
remedy?
o We are not aware of any other information which could affect the protectiveness
of the remedy.
i
¦ Have newly found ecological risks been found?
o No.
7-4
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
8. ISSUES
As noted, PCE concentrations have increased in Site groundwater monitoring wells during the 2009 to
2013 period. Four of these wells were selected for localized hot spot treatment during the Fall of 2013.
The effectiveness of this latest hot spot treatment is currently being monitored. ACC/GCC will submit a
report describing the results of this hot spot treatment event to the EPA following the collection of one
year of analytical data, with reporting anticipated for early 2015. Periodic PCE hot-spot treatment
injections are available as contingency measures as part of the OU 1 remedy as described in the 2013
Contingency Plan.
8-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
9. RECOMMENDATIONS AND FOLLOW-UP ACTIONS
Issue
Recommendations
and
Follow-up Actions
/
Responsible
Party
Oversight
Agency
Mile-
stone
Date
Affects
Protectiveness
(Y/N)
Current
Future
Hot Spot
Treatment
Evaluation
ACC/GCC to
evaluate results from
Fall 2013 hot spot
treatment event and
report to the EPA.
Additional hot spot
treatment may be
implemented in the
future based on the
review and evaluation
of future groundwater
monitoring results.
ACC/GCC
EPA
2/2015
(
N
N
9-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
10. PROTECTIVENESS STATEMENT
The OU 1 remedy is protective of human health and the environment.
The OU 2 remedy is protective of human health and the environment.
Because the remedial actions at all OUs are protective, the site is protective of human health and the
environment.
10-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
11. NEXT REVIEW
The next five-year review for the Chemplex site is tentatively scheduled for June 2019, five years from
the date of this review.
11-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
12. REFERENCES
City of Camanche. 2009. Ordinance No. 697 -An Ordinance Amending the Code of Ordinances to The
City of Camanche, Iowa, by Adopting Provisions Pertaining to Connections to the Public Water
System and Restricting the Installation of New Wells for Domestic Use where City Water is
Available. May 5.
Erler & Kalinowski, Inc. (EKI). 2008. Final Contingency Plan for Exposure Control Performance Test,
Chemplex Site, Clinton, Iowa - First and Second Operable Units. September 19.
EKI. 2009a. Quarterly Report for Reporting Period 1 January 2009 through 31 March 2009, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. April 29.
EKI. 2009b. Quarterly Report for Reporting Period 1 April 2009 through 30 June 2009, Chemplex Site,
Clinton, Iowa — First and Second Operable Units. July 30.
EKI. 2009c. Quarterly Report for Reporting Period 1 July 2009 through 30 September 2009, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. October 27.
EKI. 2010a. Quarterly Report for Reporting Period 1 October 2009 through 31 December 2009,
Chemplex Site, Clinton, Iowa — First and Second Operable Units. January 28.
EKI. 2010b. Quarterly Report for Reporting Period 1 January 2010 through 31 March 2010, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. April 27.
EKI. 2010c. Quarterly Report for Reporting Period 1 April 2010 through 30 June 2010, Chemplex Site,
Clinton, Iowa — First and Second Operable Units. July 28.
EKI. 2010d. Quarterly Report for Reporting Period 1 July 2010 through 30 September 2010, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. October 27.
EKI. 2011a. Quarterly Report for Reporting Period 1 October 2010 through 31 December 2010,
Chemplex Site, Clinton, Iowa -- First and Second Operable Units. January 28.
EKI. 2011b. Quarterly Report for Reporting Period 1 January 2011 through 31 March 2011, Chemplex
Site, Clinton, Iowa - First and Second Operable Units. April 28.
EKI. 2011c. Quarterly Report for Reporting Period 1 April 2011 through 30 June 2011, Chemplex Site,
Clinton, Iowa -- First and Second Operable Units. July 28.
EKI. 201 Id. Quarterly Report for Reporting Period 1 July 2011 through 30 September 2011, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. October 28.
EKI. 2012a. Quarterly Report for Reporting Period 1 October 2011 through 31 December 2011,
Chemplex Site, Clinton, Iowa — First and Second Operable Units. January 30.
12-1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
EKI. 2012b. Updated Focused Feasibility Study, Operable Unit No. 1 for Groundwater, Chemplex Site,
Clinton, Iowa. February 8.
EKI. 2012c. Quarterly Report for Reporting Period 1 January 2012 through 31 March 2012, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. April 26.
EKI. 2012d. Quarterly Report for Reporting Period 1 April 2012 through 30 June 2012, Chemplex Site,
Clinton, Iowa — First and Second Operable Units. July 30.
EKI. 2012e. Quarterly Report for Reporting Period 1 July 2012 through 30 September 2012, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. October 30.
EKI. 2013a. Quarterly Report for Reporting Period 1 October 2012 through 31 December 2012,
Chemplex Site, Clinton, Iowa — First and Second Operable Units. January 30.
EKI. 2013b. Quarterly Report for Reporting Period 1 January 2013 through 31 March 2013, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. April 26.
EKI. 2013c. Performance Monitoring Evaluation Plan Addendum No. 4, Chemplex Site - First
Operable Unit. April 26.
EKI. 2013d. Summary of Results from May 2013 In-Situ Groundwater and Surface Water Sampling
Event, Chemplex Site, Clinton, Iowa — First Operable Unit. July 22.
EKI. 2013e. Quarterly Report for Reporting Period 1 April 2013 through 30 June 2013, Chemplex Site,
Clinton, Iowa -- First and Second Operable Units. July 29.
EKI. 2013f. Quarterly Report for Reporting Period 1 July 2013 through 30 September 2013, Chemplex
Site, Clinton, Iowa — First and Second Operable Units. October 31.
EKI. 2013g. 2013 Contingency Plan, Chemplex Site, Clinton, Iowa, First Operable Unit. October 25.
EPA. 1989. Record of Decision - The Landfill and DAC Areas, Groundwater Operable Unit, Chemplex
Site, Clinton, Iowa. September 27.
EPA. 1991. Explanation of Significant Differences (to the September 27, 1991 Record of Decision),
ChemplexSite, Clinton, Iowa. July 26.
EPA. 1991. Consent Decree (for the Remedial Design/Remedial Action, Chemplex Site, Clinton Iowa).
United States of America versus ACC Chemical Company, Four Star Oil and Gas, Getty
Chemical Company, Primerica Holdings, Inc., Skelly Oil Company, Quantum Chemical
Corporation, and the City of Clinton, Iowa. Civil Action No. 3-91-CV-70096. November 7.
EPA. 1993. Record of Decision, Second Operable Unit, Chemplex Site, Clinton, Iowa., May 12.
12-2
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
1995. Consent Decree (for the Remedial Design/Remedial Action, OU 2, Chemplex Site, Clinton
Iowa).). United States of America versus ACC Chemical Company, Four Star Oil and Gas,
Getty Chemical Company, The Travelers, Inc., Quantum Chemical Corporation, and the City of
Clinton, Iowa. Civil Action No. 3-91-CV-70096. February 6.
1999. Five-Year Review Report, Chemplex Site, Clinton, Iowa. June 9.
2001. Comprehensive Five-Year Review Guidance. EPA 540-R-01-007, OSWER No. 9355.7-03B-
P. Office of Emergency and Remedial Response, U.S. Environmental Protection Agency,
Washington, D.C. 20460. June.
2003. Region 5 RCRA Ecological Screening Levels.
http://epa.gov/region5/waste/cars/pdfs/ecological-screening-levels-200308.pdf
2004. Second Five-Year Review Report for Chemplex Site, Clinton, Iowa. June 9.
2009. Third Five-Year Review Report for Chemplex Site, Clinton, Iowa. June 5.
2012. Amendment to the Record of Decision, Chemplex Superfiind Site, Operable Unit No. 1 -
Groundwater, December 26.
Golder Associates, Inc. 1998. Operation and Maintenance Plan, Operable Unit No. 2, Chemplex Site,
Clinton, Iowa. May 8.
Montgomery Watson. 1993. Performance Monitoring Evaluation Plan for Chemplex Site in Clinton,
Iowa. November 1.
Montgomery Watson Harza (MWH). 2008. Final Contingency Plan for Exposure Control Performance
Test, Chemplex Site, Clinton, Iowa - First and Second Operable Units. September 19.
MWH. 2008. Performance Monitoring Evaluation Plan for Chemplex Site in Clinton, Iowa. MWH,
October 3.
MWH. 2009. Hot Spot Pilot Test Field Activities Summary, Chemplex Site, Operable Unit 1, Clinton,
Iowa. October 29.
MWH. 2010a. PME Plan Addendum 1, Chemplex Site - 2010 Sampling and Gauging Schedule. March
15.
MWH. 2010b. Hot Spot Pilot Test 6-Month Progress Report, Chemplex Site, Operable Unit 1, Clinton,
Iowa. May.
MWH. 2010c. Hot Spot Pilot Test Evaluation Report for Chemplex Site in Clinton, Iowa. December.
MWH. 2011. PME Plan Addendum 2, Chemplex Site - 2011 Sampling and Gauging Schedule. April 11.
MWH. 2012. PME Plan Addendum 3, Chemplex Site - 2012 Sampling and Gauging Schedule. April 4.
12-3
EPA.
EPA.
EPA.
EPA.
EPA.
EPA.
EPA.
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
MWH. 2013. PME Plan, Addendum 4, Chemplex Site - First Operable Unit, 2013. April.
12-4
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
Tables
-------
TABLE 1
Chronology of Site Events
Chemplex Site -- Clinton, Iowa
Date
Operable
Unit
Event or Submittal
1968
Chemplex facility started operation
10/15/1984
Proposed for National Priorities List (NPL)
09/08/1987
Consent Order for Remedial Investigation/Feasibility Study (RI/FS)
09/27/1989
OU 1
Record of Decision (ROD) Issued
12/28/1989
OU 2
Administrative Order on Consent (AOC) for RI/FS
02/11/1991
Withdrawn from list of sites proposed for the NPL
07/26/1991
OU 1
Explanation of Significant Differences (ESD) issued by EPA
11/07/1991
OU 1
Consent Decree (CD) for Remedial Design/Remedial Action (RD/RA) entered
05/12/1993
OU 2
ROD issued by EPA
11/01/1993
OU 1
Performance Monitoring Evaluation (PME) Plan submitted to EPA
02/02/1994
OU 1
RD completed
05/31/1994
OU 1
RA construction began
Dec. 1994
OU 1
Groundwater extraction and treatment system begins active operation
02/06/1995
OU 2
CD for RD/RA entered
02/16/1995
OU 1
Groundwater extraction achieves full startup with all extraction wells online
09/14/1995
OU 1
Preliminary Close Out Report signed
12/18/1996
OU 2
RD completed
Feb. 1998
OU 2
Landfill Gas Extraction (LGE) System begins active operation
06/09/1999
First Five Year Review issued by EPA
04/09/2003
OU 2
Soil Vapor Extraction system ceased operation, with EPA approval
06/09/2004
Second Five Year Review issued by EPA
Nov. 2005
OU 1
Suspension of groundwater extraction from Landfill Wells and Farmers Creek Wells,
with EPA approval
20 July 2007
OU 1
ACC/GCC submits Final Focused Feasibility Study Report (FFFS)
04/09/2008
OU 1
EPA issues Statement of Additional Work (SOAW) and conditionally approves shutting
down the groundwater extraction system, subject to completion of actions and
documents outlined in the SOAW.
Apr. 2008
OU 1
ACC/GCC performs baseline groundwater sampling.
July 2008
OU 1
Revised PME Plan submitted
09/26/2008
OU 1
EPA approves shutdown of groundwater extraction system and placement into long-
term standby service for remedy performance testing.
03/17/2009
OU 1
Hot Spot Pilot Test Work Plan submitted
06/05/2009
Third Five-Year Review issued by EPA
05/05/2010
OU 1
Hot Spot Pilot Test Six-month Progress Report submitted
Fall 2010
OU 1
City of Camanche waterline extension and all residential connections completed
12/21/2010
OU 1
Hot Spot Pilot Test Evaluation Report submitted
02/08/2012
OU 1
Updated Focused Feasibility Study Report for OU 1 (UFFS) submitted
02/17/2012
OU 1
Proposed Plan for revised remedy issued by EPA
02/27/2012
OU 1
Public meeting to discuss Proposed Plan for revised remedy
12/26/2012
OU 1
ROD Amendment issued by EPA
-------
Table 2
Groundwater Cleanup Goals
Chemplex Site - Clinton, Iowa
Compound
Former Groundwater
Cleanup Goals as of
1999 (ug/L) (a)
New Groundwater
Cleanup Goals (ug/L) in
ROD Amendment
Notes
Volatile Organic Compounds
Benzene
1
5
(h)
1,2-Dichlorobenzene
600
600
1,1-Dichloroethene
7
.7
(h)
1,2-Dichloroethene (sum of cis and trans isomers)
70
- (b)
(b),(h)
cis-1,2-Dichloroethene
-
70
(h)
trans-1,2-Dichloroethene
-
100
Ethylbenzene
700
700
Methylene Chloride
5
5
(c)
Styrene
100
100
1,1,2,2-Tetrachloroethane
0.2
-(d)
Tetrachloroethene
5
5
(h)
Toluene
2,000
1,000
1,1,1-Trichloroethane
200 .
200
Trichloroethene
3
5
(h)
Vinyl Chloride
0.015
2
(h)
Xylenes
10,000
10,000
Polynuclear Aromatic Hydrocarbons
Benzo(a)pyrene
0.2
0.2
(e)
Naphthalene
20
1.4
(f)
Metals
Antimony
3
6
Arsenic
0.03
10
(g)
Barium
2,000
2,000
Notes:
(a) Cleanup Goals are as shown in the Five Year Report for the Chemplex Site, dated 9 June 1999 and prepared by the
U. S. Environmental Protection Agency, Region 7. The groundwater cleanup goals for the then-current remedy were
established based on Chapter 133 of the Iowa Administrative Code, which became effective in 1989. These
provisions set forth a hierarchical approach to set "action levels" that, if exceeded, would require identification of the
nature and extent of a release. These action levels were not intended by the Iowa Department of Natural Resources
to be established as cleanup levels. The hierarchy to select action levels was: (1) select the Lifetime Health
Advisory Level (HAL), if one exists; (2) if no HAL exists, select the Negligible Cancer Risk Level (NRL); and (3) if no
HAL or NRL exists, select the drinking water Maximum Contaminant Level (MCL). Under current regulatory practice
in the State of Iowa, MCLs are now commonly applied for "protected" groundwater sources.
(b) The Consent Decree for the Chemplex First Operable Unit, dated September 1990, set forth a Groundwater Cleanup
Standard of 70 micrograms per liter (ug/L) for total 1,2-Dichloroethene (Total 1,2-DCE) based on the then-current
Health Advisory Level (HAL). This standard was established for the total of the cis and trans isomers because the
analytical instruments at that time could not readily separate and report the two isomers individually. Because
modem instruments can report the concentration of each isomer, and because both isomers now have Federal
Drinking Water Maximum Contaminant Levels (MCLs), a Groundwater Cleanup Goal will be established for each
isomer that is equal to its MCL. A cleanup goal for Total 1,2-DCE is thus no longer needed.
Page 1 of 2
-------
Table 2
Groundwater Cleanup Goals
Chemplex Site - Clinton, Iowa
(c) Methylene chloride has been sporadically detected in Site groundwater analyses. These detections of methylene
chloride, a common laboratory contaminant, in Chemplex groundwater are believed to result from laboratory
contamination in view of repeated detections of this analyte in trip and field blanks collected during Site sampling
events. Methylene chloride will continue to be evaluated in the Chemplex groundwater monitoring network.
(d) 1,1,2,2-tetrachloroethane was not detected above the current cleanup standard, and therefore does not appear to be
a chemical of concern at this Site. This analyte's cleanup standard has thus been deleted.
(e) Benzo(a)pyrene is a polynuclear aromatic hydrocarbon (PAH) associated with historic releases of debutanized
aromatic concentrate (DAC), a byproduct of ethylene production. As PAHs such as benzo(a)pyrene are generally
less mobile in groundwater compared with volatile organic compounds (VOCs), their distribution at the Chemplex
Site is not as widespread as PCE and its daughter products. Benzo(a)pyrene has occasionally been found in
groundwater downgradient of the DAC management area of the polyethylene plant.
(f) Naphthalene is a PAH associated with historic releases of DAC and potentially with wastes disposed of in the
Chemplex Landfill. The 1990 Consent Decree used the HAL for naphthalene, 20 ug/L, as a surrogate for
establishment of cleanup standards for a number of non-carcinogenic PAHs. EPA has not established an MCL for
naphthalene. EPA has now determined that naphthalene may be a carcinogen, and has set a concentration of 1.4
ug/L, equivalent to a risk level of one-in-one hundred thousand (10"5), as a presumptive groundwater cleanup goal.
As PAHs such as naphthalene are generally less mobile in groundwater compared with VOCs, their distribution at
the Chemplex Site is not as widespread as PCE and its daughter products. Naphthalene has occasionally been
found at levels below 20 ug/L but above 1.4 ug/L in groundwater immediately downgradient of the DAC management
area. Naphthalene has also been occasionally detected above 1.4 ug/L in the far downgradient area of the
Chemplex groundwater monitoring network. Given this analyte's limited mobility and the lack of a discernible
naphthalene plume emanating from the plant area, it is not believed these far downgradient detections result from
past plant operations.
(g) Arsenic has been detected at the Chemplex Site at concentrations greater than the Proposed Groundwater Cleanup
Goal. However, high background levels of arsenic are typical in Iowa. The Chemplex Site is not a confirmed source
of metals, including arsenic. With EPA's concurrence, arsenic and other metals are no longer routinely sampled in
Site groundwater.
(h) Groundwater cleanup standard is subject to a Tl waiver within the Tl Zone.
Abbreviations:
HAL = Health Advisory Level
MCL = Maximum Contaminant Level
NRL = Negligible Risk Level
ug/L = micrograms per liter
Page 2 of 2
-------
TABLE 3
Summary of Sampling Required by the 2013 PME
Plan and PME Plan Addendum 4
Chemplex Site -- Clinton, Iowa
Sampling
Location
2013 Frequency (1)
Required Analyses
Last Sampling Event
3
Semiannual
VOCs
18 to 20 November 2013
ARC MW-200B
Semiannual
VOCs
18 to 20 November 2013
ARC MW-200C
Semiannual
VOCs
18 to 20 November 2013
ARC MW-200D
Semiannual
VOCs
18 to 20 November 2013
ARC MW-201B
Annual
VOCs
6 to 8 May 2013
ARC MW-201C
Annual
VOCs
6 to 8 May 2013
ARC MW-205B
Annual
VOCs
6 to 8 May 2013
ARC MW-205C
Annual
VOCs
6 to 8 May 2013
ARC MW-205D
Annual
VOCs
6 to 8 May 2013
ARC MW-206B
Annual
VOCs
6 to 8 May 2013
ARC MW-207B
Annual
VOCs
6 to 8 May 2013
ARC MW-207C
Annual
VOCs
6 to 8 May 2013
ARC MW-208B
Annual
VOCs
6to8May2013
ARC MW-208C
Annual
VOCs
6 to 8 May 2013
ARC MW-209BC
Semiannual
VOCs
18 to 20 November 2013
ARC MW-211C
Semiannual
VOCs
18 to 20 November 2013
DG-16
Annual
VOCs
6 to 8 May 2013
DG-18B
Semiannual
VOCs
18 to 20 November 2013
DG-21B
f Semiannual
VOCs
18 to 20 November 2013
DG-21C
Semiannual
VOCs
18 to 20 November 2013
EW-3a
Annual
VOCs
6 to 8 May 2013
EW-6c
Annual
VOCs
6 to 8 May 2013
EW-7a
Semiannual
VOCs
18 to 20 November 2013
EW-7b
Annual
VOCs
6 to 8 May 2013
EW-11a
Annual
VOCs
6 to 8 May 2013
EW-11b
Annual
VOCs
6 to 8 May 2013
EW-11c
Annual
VOCs
6 to 8 May 2013
EW-13b
Annual
VOCs
6 to 8 May 2013
EW-14b
Annual
VOCs
6 to 8 May 2013
EW-14c
Semiannual
VOCs
18 to 20 November 2013
MUNCK (2)
Annual
VOCs, PAHs
6 to 8 May 2013
MW-18B
Annual
VOCs
6 to 8 May 2013
MW-18C
Semiannual
VOCs
18 to 20 November 2013
MW-53A
Semiannual
VOCs
18 to 20 November 2013
MW-57-1
Semiannual
VOCs
18 to 20 November 2013
MW-70
Annual
VOCs
6 to 8 May 2013
MW-73
Semiannual
VOCs
18 to 20 November 2013
MW-82B
Annual
VOCs
6 to 8 May 2013
MW-82C
Annual
VOCs
6 to 8 May 2013
MW-85B
Annual
VOCs
6 to 8 May 2013
MW-85C
Annual
VOCs
6 to 8 May 2013
3
Semiannual
VOCs
18 to 20 November 2013
' MW-94A
Annual
VOCs
6 to 8 May 2013
Page 1 of 3
-------
TABLE 3
Summary of Sampling Required by the 2013 PME
Plan and PME Plan Addendum 4
Chemplex Site -- Clinton, Iowa
Sampling
Location
2013 Frequency (1)
Required Analyses Last Sampling Event
MW-97A
Semiannual
VOCs
18 to 20 November 2013
MW-97C
Annual
VOCs
6 to 8 May 2013
MW-99A
Semiannual
VOCs
18 to 20 November 2013
MW-103B
Semiannual "
VOCs
18 to 20 November 2013
MW-103C
Semiannual
VOCs
18 to 20 November 2013
MW-103D
' Semiannual
VOCs
18 to 20 November 2013
MW-104B
Annual
VOCs
6 to 8 May 2013
MW-104C
Annual
VOCs
6 to 8 May 2013
MW-105B
Semiannual
VOCs
18 to 20 November 2013
MW-105C
Semiannual
VOCs
18 to 20 November 2013
MW-106A
Semiannual
VOCs
18 to 20 November 2013
MW-106B
Semiannual
VOCs
18 to 20 November 2013
MW-106C
Semiannual
VOCs
18 to 20 November 2013
MW-107A
Semiannual
VOCs
18 to 20 November 2013
MW-107B
Semiannual
VOCs
18 to 20 November 2013
MW-107C
Semiannual
VOCs
18 to 20 November 2013
MW-108B
Annual
VOCs
6 to 8 May 2013
MW-108C
Annual
VOCs
6 to 8 May 2013
MW-109B
Semiannual
VOCs
18 to 20 November 2013
MW-109C
Semiannual
VOCs
18 to 20 November 2013
MW-110B
Annual
VOCs
6 to 8 May 2013
MW-112A
Annual
VOCs
6 to 8 May 2013
MW-113A
Semiannual
VOCs
18 to 20 November 2013
MW-116A
Semiannual
VOCs
18 to 20 November 2013
MW-117B
Annual
VOCs
6 to 8 May 2013
MW-117C
Semiannual
VOCs
18 to 20 November 2013
MW-118C
Annual
VOCs
6 to 8 May 2013
MW-119A
Semiannual
VOCs
18 to 20 November 2013
MW-119B
Semiannual
VOCs
18 to 20 November 2013
MW-119C
Semiannual
VOCs
18 to 20 November 2013
MW-120A
Annual
VOCs
6 to 8 May 2013
MW-120B
Annual
VOCs
6 to 8 May 2013
MW-121A
Annual
VOCs
6 to 8 May 2013
MW-121B
Annual
VOCs
6 to 8 May 2013
MW-121C
Annual
VOCs
6 to 8 May 2013
MW-122A
Annual
VOCs
6 to 8 May 2013
MW-122B
Annual
VOCs
6 to 8 May 2013
MW-122C
Annual
VOCs
6 to 8 May 2013
MW-129A
Semiannual
VOCs
18 to 20 November 2013
3
Semiannual
VOCs
18 to 20 November 2013
SW-1
Semiannual
VOCs, PAHs
18 to 20 November 2013
SW-2
Semiannual
VOCs, PAHs
18 to 20 November 2013
SW-3
Semiannual
VOCs, PAHs .
18 to 20 November 2013
Page 2 of 3
-------
TABLE 3
Summary of Sampling Required by the 2013 PME
Plan and PME Plan Addendum 4
Chemplex Site -- Clinton, Iowa
Sampling
Location
2013 Frequency (1)
Required Analyses Last Sampling Event
SW-4
Semiannual
VOCs, PAHs
18 to 20 November 2013
WELL 1Q
Once
VOCs
6 to 8 May 2013
WELL 4Q
Once
VOCs
6 to 8 May 2013
WELL 6Q
Once
VOCs
6 to 8 May 2013
WELL 7Q
Once
VOCs
6 to 8 May 2013
Notes:
(1) Sampling frequency as indicated in the 2013 PME Plan Addendum 4, dated 26 April 2013.
Annual - location to be sampled once, in Spring 2013.
Semiannual - locations to be sampled twice, in Spring and Fall 2013.
Once - location to be sampled once in 2013 (sampled in odd-numbered years only).
(2) ACC/GCC may sample residential wells from time to time on a voluntary basis. The Munck
residential well was sampled on this basis in 2013, and is anticipated to be sampled again in 2014
Abbreviations:
EPA = Environmental Protection Agency, Region 7
PME = Performance Monitoring Evaluation
Page 3 of 3
-------
TABLE 4
Summary of VOCs Detected in Equistar Production Wells - 2009 through 2013
Chemplex Site -- Clinton, Iowa
Concentration in ug/L (a)
Sample Location
Sample Date (b)
cis-1,2-Dichloroethene
Methylene Chloride (c)
Tetrachloroethene
Trichloroethene
(
All Other VOCs
5/14/2009
0.5 U
0.5 U
0.5 U
0.5 U
ND
WELL 1Q
5/25/2011
0.5 U
8.1 UB
0.5 U
0.5 U
ND
5/8/2013
0.5 U
0.5 U
0.5 U
0.5 U
ND
5/14/2009
0.5 U
0.5 U
0.5 U
0.5 U
ND
WELL 4Q
5/25/2011
0.5 U
5.6 UB
0.5 U
0.5 U
ND
5/8/2013
0.5 U
0.5 U
0.5 U
0.5 U
ND
5/14/2009
0.5 U
0.5 U
0.5 U
0.5 U
ND
WELL 6Q
5/25/2011
0.5 U
5.1 UB
0.5 U
0.5 U
ND
5/8/2013
0.5 U
0.5 U
0.5 U
0.5 U
ND
5/14/2009
0.5 U
0.5 U
0.5 U
0.5 U
ND
WELL 7Q
5/25/2011
0.5 U
4.9 UB
0.5 U
0.5 U
ND
5/8/2013
0.5 U
0.5 U
0.5 U
0.5 U
ND
Abbreviations:
ND = Not Detected. ug/L = micrograms per titer. VOC = volatile organic compound.
Notes:
(a) A "U" following the value indicates that the analyte was not detected above the method detection limit indicated. A "UB" following the value indicates that the analyte
was detected at a similar concentration in a blank, and therefore the analyte is considered to be not detected.
(b) Under the 2008 Performance Monitoring Evaluation Plan and subsequent addenda, the Equistar Production Wells are sampled only in odd-numbered years and thus
were not sampled in 2010 and 2012.
-------
TABLE 5
Wells Downgradient of the Equistar Property with Detected Chemical
Concentrations Exceeding
Cleanup Goals during 2013 Sampling Events (a)
Chemplex Site -- Clinton, Iowa
Screened Layer
Site
Region
Well ID
Analyte Exceeding
Cleanup Standard
Cleanup
Goal
(ug/L)
May 2013
Detected
Concentration
(ug/L)
November 2013
Detected
Concentration
(ug/L)
3
PCE
5
450
640
Overburden
West
TCE
5
21
25
MW-53A
PCE
5
190
88
TCE
5
16
15
DG-21B
PCE
5
20
23
TCE
5
6.8
11
EW-7a
PCE
5
980
1000
TCE
5
28
35
Upper Scotch
Grove
West
1,1-DCE
7
11
-
cis-1,2-DCE
70
130
-
EW-11a
PCE
5
100
-
TCE
5
53
-
VC
2
2.3
-
MW-97A
PCE
5
6
25
East
MW-106A
PCE
5
43
62
DG-21C
PCE
5
14
16
West
TCE
5
5.7
8.3
MW-110B
PCE
5
8.7/11 (b)
-
Lower Scotch
MW-106B
PCE
5
7.2
8.2
Grove
MW-107B
PCE
5
19
22
East
cis-1,2-DCE
70
170
<0.5
MW-109B
PCE
5
1100
<0.5
TCE
5
55
<0.5
MW-97C
PCE
5
51
-
West
EW-11b
PCE
5
110
-
TCE
5
42
-
MW-106C
PCE
5
160
4.2
Farmers Creek
TCE
5
8.6
<0.5
East
MW-107C
PCE
5
24
24
PCE
5
740
<1
MW-109C
TCE
5
33
<1
cis-1,2-DCE
70
110
<1
Abbreviations:
1,1-DCE = 1,1-dichloroethene TCE = trichloroethene cis-1,2-DCE =
cis-1,2-dichloroethene ug/L = micrograms per liter
PCE = tetrachloroethene VC = vinyl chloride
Notes:
(a) For purposes of this Table, "downgradient of the Site" is considered to be south of 21st Street (also
known as Hawkeye Road).
(b) Duplicate samples were collected.
-------
TABLE 6
Summary of VOCs Detected in Surface Water - January 2009 through November 2013
Chemplex Site - Clinton, Iowa
Sample ID (c)
Sample Date
Concentration in ug/L (a) (b)
Acetone (d)
Benzene
Butanone (d)
Chloromethane
1,1-Dichloroethene
cis-1,2-
Dichloroethene
Trans-1,2-
Dichloroethene
Methylene Chloride
T etrachloroethene
Toluene
Trichloroethene
Trichlorotrifluoroeth
ane
Vinyl Chloride
Surface Water Trigger Level
-
-
-
-
-
590
-
-
98
-
80
-
25
SW-1
5/11/2009
6.9 U
0.3 J
5 U
0.5 U
0.5 U
9.2
0.5 U
0.5 U
4.3
0.5 U
1.8
0.5 u
0.5 U
SW-1 (DUP)
5/11/2009
5 U
0.32 J
5 U
0.5 U
0.5 U
9.4
0.5 U
0.5 U
4.1
0.5 U
2
0.5 U
0.5 U
SW-1
8/4/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
9.4
0.5 U
0.5 U
3
0.5 U
0.9
0.5 U
0.5 U
SW-1 (DUP)
8/4/2009
5.2 U
0.5 U
5 U
0.5 U
0.5 U
9.2
0.5 U
0.5 U
2.5
0.5 U
0.86
0.5 U
0.5 U
SW-1
11/3/2009
5 U
0.5.U
5 U
0.5 U
0.5 U
11
0.5 U
0.25 J
5.1
0.5 U
1-4
0.5 U
0.27 J
SW-1 (DUP)
11/3/2009
5 U
0.5 U
. 5 U
0.5 U
0.5 U
11
0.5 U
0.28 J
4.9
0.5 U
1.2
0.5 U
0.28 J
SW-1
5/13/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
9.7
0.5 U
0.71 UB
4.6
0.5 U
0.8
0.5 U
0.43 J
SW-1 (DUP)
5/13/2010
5 U
0:5 U
5 U
0.5 U
0.5 U
9.4
0.5 U
1.3 UB
4.7
0.5 U
0.72
0.5 U
0.5
SW-1
11/2/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
23
0.5 U
0.78 UB
2.1
0.5 U
0.9
0.5 U
0.73
SW-1 (DUP)
11/2/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
23
0.5 U
0.5 U
2.6
0.5 U
0.9
0.5 U
0.74
SW-1
5/24/2011
2.9 J
0.5 U
5 U
0.5 U
0.5 U
16 J
0.5 U
0.54 UB
1.7 UB
0.5 U
0.56
0.5 U
0.45 J
SW-1 (DUP)
5/24/2011
2.5 J
0.5 U
5 U
0.5 U
0.5 U
15
0.5 U
0.52 UB
1.7
0.5 U
0.61
0.5 U
0.56
SW-1
11/9/2011
5 U
0.5 U
5 U
0.5 U
0.5 U
12
0.5 U
33 UB
4.2
0.5 U
0.99
0.5 U
0.89
SW-1 (DUP)
11/9/2011
5 U
0.5 U
5 U
0.5 U
0.5 U
13
0.5 U
16 UB
4.4
0.5 U
1.0
0.5 U
0.98
SW-1
5/2/2012
5 U
0.5 U
5 U
0.5 U
0.5 U
28
0.5 U
5.7 B
5.2
0.5 U
1.7
.0.5 U
0.97
SW-1 (DUP)
5/2/2012
5 U
0.5 U
5 U
0.5 U
0.5 U
27
0.5 U
4.6 B
4.8
0.5 U
1.5
0.5 U
0.88
SW-1
10/31/2012
2.3 J
0.5 U
5 U
0.5 U
0.5 U
56
0.3 J
2.1 UB
1.9
0.5 U
1.4
0.5 U
1.8
SW-1 (DUP)
10/31/2012
2.1 J
0.5 U
5 U
0.5 U
0.5 U
54
0.32 J
0.33 UB
2.0
0.5 U
1.4
0.5 U
1.7
SW-1
5/7/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
33
0.5 U
0.5 U
7.2
0.5 U
2.5
0.5 U
0.93
SW-1 (DUP)
5/7/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
31
0.5 U
0.5 U
7.2
0.5 U
2.2
0.5 U
0.93
SW-1
11/20/2013
5 U
0.5 U
5 U
0.5 U
0.3 J
93
0.41 J
0.5 U
1.9
0.5 U
1.3
0.5 U
2.4
SW-1 (DUP)
11/20/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
100
0.53
0.5 U
1.6
0.5 U
1.4
0.5 U
2.6
SW-2
5/11/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
0.23 J
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
8/5/2009
4 U
0.5 U
4 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
11/4/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.25 J
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
5/12/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.22 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
Page 1 of 3
-------
TABLE 6
Summary of VOCs Detected in Surface Water - January 2009 through November 2013
Chemplex Site - Clinton, Iowa
Sample ID (c)
Sample Date
Concentration in ug/L (a) (b)
Acetone (d)
Benzene
Butanone (d)
Chloromethane
1,1-Dichloroethene
cis-1,2-
Dichloroethene
Trans-1,2-
Dichloroethene
Methylene Chloride
T etrachloroethene
Toluene
Trichloroethene
T richlorotrifluoroeth
ane
Vinyl Chloride
Surface Water Trigger Level
-
-
-
-
-
590
-
-
98
-
80
¦-
25
SW-2
11/2/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
5/24/2011
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
11/9/2011
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
16 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
5/2/2012
R
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.56 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
10/30/2012
2.3 J
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.67
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
5/7/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
0.37 J
0.5 U
0.5 U
0.39 J
0.5 U
0.5 U
0.5 U
0.5 U
SW-2
11/19/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.44 J
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
5/11/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
0.67
0.5 U
0.5 U
0.35 J
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
8/4/2009
6 U
0.5 U
4 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
11/4/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
1.8
0.5 U
0.35 J
1.5
0.5 U
0.29 J
0.5 U
0.5 U
SW-3
5/12/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.88 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
11/2/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
0.75
0.5 U
0.5 U
1.5
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
5/24/2011
3.5 J
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.85 UB
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
11/9/2011
2.7 J
0.51
5 U
0.5 U
0.5 U
0.44 J
0.5 U
19 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
5/2/2012
5 U
0.5 U
5 U
0.5 U
0.5 U
0.37 J
0.5 U
3.4 UB
0.4 J
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
10/30/2012
2.7 J
0.5 U
5 U
0.5 U
0.5 U
0.89
0.5 U
0.5 U
1.5
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
5/7/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
0.76
0.5 U
0.5 U
0.61
0.5 U
0.5 U
0.5 U
0.5 U
SW-3
11/20/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.37 J
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
5/11/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
8/5/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
11/4/2009
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
5/12/2010
5 U
0.5 U
5 U | 0.5 U
0.5 U
0.5 U
0.5 U
0.58 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
11/2/2010
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.21 J
0.5 U
0.5 U
0.5 U
SW-4
5/24/2011
3.2 J
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
11/9/2011
5 U
0.36 J
5 U
0.5 U
0.5 U
0.34 J
0.5 U
27 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
5/2/2012
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.42 UB
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
Page 2 of 3
-------
TABLE 6
Summary of VOCs Detected in Surface Water - January 2009 through November 2013
Chemplex Site - Clinton, Iowa
Concentration in ug/L (a) (b)
Sample ID (c)
Sample Date
Acetone (d)
Benzene
Butanone (d)
Chloromethane
1,1-Dichloroethene
cis-1,2-
Dichloroethene
Trans-1,2-
Dichloroethene
Methylene Chloride
Tetrachloroethene
Toluene
Trichloroethene
Trichlorotrifluoroeth
ane
Vinyl Chloride
Surface Water Trigger Level
-
-
-
-
-
590
-
-
98
-
80
-
25
SW-4
10/31/2012
2.9 J
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW-4
5/7/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.54
0.5 U
0.5 U
0.5 U
SW-4
11/19/2013
5 U
0.5 U
5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
Notes:
(a) Only VOCs that have been detected using U.S. Environmental Protection Agency (EPA) Method 8260 insurface water samples SW-1
through SW-4 are shown in this table. Naphthalene, which is a semivolatile organic compound (SVOC) that has been historically
detected in surface water samples at trace levels using EPA Method 8270, has not been detected using EPA Method 8260 and is
therefore not shown in this table.
(b) Boldface type indicates concentration was detected above method detection limit and represents a valid detection.
"B" following value indicates that the analyte was detected in the method blank and therefore the measured result may be invalid or
may be biased high.
"J" following value indicates that the analyte was detected at the concentration shown, but that the value was greater than the method
detection limit, and less than the laboratory practical quantitation limit.
"R" following value indicates that the value was rejected based on a data validation evaluation.
"U" following value indicates that the analyte was not detected above the method detection limit indicated.
"UB" indicates the analyte was qualified not detected because it was detected at a similar concentration in a blank.
(c) SW-1 was collected from the Western Un-Named Tributary (West Trib) at its crossing under 21st Street. SW-2 was collected from
the Eastern Un-Named Tributary (East Trib). SW-3 was collected at Rock Creek, just downstream of its confluence with the West
Trib. SW-4 was collected at Rock Creek, just downstream of its confluence with the East Trib.
(d) This analyte is a common laboratory contaminant. Therefore, sporadic measurements at low levels are not consideredto be valid
detections.
Abbreviations:
- = not analyzed DUP = duplicate
ug/L = micrograms per liter VOC = volatile organic compound
Page 3 of 3
-------
TABLE 7
Summary ofPAHs Detected in Groundwater and Surface Water - January 2009 through November 2013
Chemplex Site -- Clinton, Iowa
Sample ID
Sample
Date
Concentration in ng/L (a)
Acenaphthene
I
Acenaphthylene
Anthracene
Benzo(a)anthracene
Benzo(a)pyrene
-------
TABLE 7
Summary ofPAHs Detected in Groundwater and Surface Water - January 2009 through November 2013
Chemplex Site -- Clinton, Iowa
Sample ID
Sample
Date
Concentration in pg/L (a)
Acenaphthene
Acenaphthylene
Anthracene
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(g,h,i)perylene
Benzo(k)fluoranthene
Chrysene
Dibenzo(a,h)anthracene
Fluoranthene
Fluorene
lndeno(l,2,3-cd)pyrene
Naphalene
Phenanthrene
Pyrene
Groundwater Cleanup
Goal (ug/L)
-
-
-
-
0.2
-
-
-
-
-
-
-
-
1.4
-
-
SW-1
5/13/2010
0.032 J
0.043 J
0.05 U
0.05 U
0.05 U
0.05 U-
0.015 J
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.046 J
0.034 J
0.05 U
5/13/2010
0.027 J
0.037 J
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.029 J
0.026 J
0.05 U
11/2/2010
0.029 J
0.029 J
0.05 U
0.05 U
0.016 J
0.02 J
0.20 UB
0.018 J
0.05 U
0.20 UB
0.05 U
0.05 U
0.20 UB
0.021 J
0.035 J
0.05 UJ
11/2/2010
0.037 J
0.038 J
0.05 U
0.05 U
0.022 J
0.05
UJ
0.20 UB
0.05 UJ
0.05 U
0.20 UB
0.05 U
0.05 U
0.20 UB
0.032 J
0.044 J
0.018 J
5/24/2011
0.043 J
0.062
0.05 U
0.05 U
0.05 U
0.05 U
0.05 UJ
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.12 UB
0.50 UB
0.05 U
5/24/2011
0.054
0.06
0.05 U
0.05 U
0.05 U
0.05 U
0.05 UJ
0.05 U
0.05 U
0.05 U
0.05 U
0.02 J
0.05 U
0.46 B
0.50 UB
0.05 U
11/9/2011
0.045 J
0.10
0.018 J
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.022 J
0.03 J
0.05 U
0.20 UB
0.21 B
0.025 J
11/9/2011
0.055
0.11
0.016 J
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.024 J
0.024 J
0.05 U
0.20 UB
0.099 UB
0.023 J
5/2/2012
0.1 J
0.16 J
0.031 J
0.05
UJ
0.05
UJ
0.05
UJ
0.05 UJ
0.05 UJ
0.05 UJ
0.05 UJ
0.05 UJ
0.052 J
0.05 UJ
0.022 J
0.038 J
0.05 UJ
5/2/2012
0.063
0.13
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.015 U
0.02 J
0.05 U
10/31/2012
0.03 J
0.12
0.023 J
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.028 J
0.05 U
0.32 J
0.077 UB
0.05 U
10/31/2012
0.036 J
0.13
0.029 J
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.032 J
0.05 U
0.25 J
0.063 UB
0.05 U
5/7/2013
0.075
0.18
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.2 U
0.05 U
0.05 U
5/7/2013
0.073
0.17
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.2 U
0.05 U
0.05 U
11/20/2013
0.05 U
0.073
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.2 U
0.05 U
0.05 U
11/20/2013
0.05 U
0.069
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.05 U
0.2 U
0.05 U
0.05 U
Abbreviations:
-- = not analyzed
DUP = duplicate
ug/L = micrograms per liter
•PAH = polynuclear aromatic hydrocarbon
VOC = volatile organic compound
/
Notes:
(a) Boldface type indicates concentration was detected above method detection limit and is regarded as a valid detection.
Page 2 of 3
-------
TABLE 7
Summary of PAHs Detected in Groundwater and Surface Water - January 2009 through November 2013
Chemplex Site -- Clinton, Iowa
"B" following value indicates that the analyte was detected in the method blank and therefore the measured result may be invalid or may be biased high.
"J" following value indicates that the analyte was detected at the concentration shown, but that the value was greater than the method detection limit, and less than the
laboratory practical quantitation limit.
"R" following value indicates that the value was rejected based on a data validation evaluation.
"U" following value indicates that the analyte was not detected above the method detection limit indicated.
"UB" indicates the analyte was qualified not detected because it was detected at a similar concentration in a blank.
Page 3 of 3
-------
TABLE 8
Comparison of VOCs in Groundwater with Trigger Levels
January 2009 through November 2013
Chemplex Site -- Clinton, Iowa
Monitoring Zone and Sample ID
Maximum Concentration, 2009-2013 (ug/L) (a)
PCE
TCE
cis-1,2-DCE
VC
Contingency Well Zone Trigger Level:
10
10
140
1
ARC MW-201B
0.55
0.5 U
0.5 U
0.5 U
ARC MW-201C
0.46 J
0.5 U
0.5 U
0.5 U
ARC MW-205B
0.26 J
0.5 U
0.5 U
0.5 U
ARC MW-205C
0.5 U
0.5 U
0.5 U
0.5 U
ARC MW-205D
0.5 U
0.5 U
0.5 U
0.5 U
ARC MW-206B
0.51
0.5 U
0.5 U
0.5 U
ARC MW-211C
6.1
0.33 J
1.1
0.5 U
MW-105B
4.8
0.5 U
0.42 J
0.5 U
MW-105C
3.7
0.5 U
0.21 J
0.5 U
MW-117B
0.5 U
0.5 U
0.5 U
0.5 U
MW-117C
1.0
0.32 J
0.5 U
0.5 U
Heightened Awareness Zone Trigger Level:
10
10
140
1
ARC MW-207B
0.5 U
0.5 U
0.5 U
0.5 U
ARC MW-207C
0.62
0.5 U
0.5 U
0.5 U
ARC MW-208B
0.5 U
0.5 U
0.5 U
0.5 U
ARC MW-208C
0.5 U
0.5 U
0.5 U
0.5 U
ARC MW-209BC
1.2
0.5 U
0.5 U
0.5 U
MW-104B
0.5 U
0.5 U
0.5 U
0.5 U
MW-104C
0.5 U
0.5 U
0.5 U
0.5 U
MW-120A
0.5 U
0.5 U
0.5 U
0.5 U
MW-120B
0.5 U
0.5 U
0.5 U
0.5 U
MW-122A
0.5 U
0.5 U
0.5 U
0.5 U
MW-122B
0.5 U
0.5 U
0.5 U
0.5 U
MW-122C
0.5 U
0.5 U
0.5 U
0.5 U
Expedited Contingency Zone Trigger Level:
5
5
70
0.5
MW-119A
1.3
0.5 U
0.5 U
0.5 U
MW-119B
3.3
0.45 J
0.5 U
0.5 U
MW-119C
2.4
0.5 U
0.5 U
0.5 U
MW-121A
0.5 U
0.5 U
0.5 U
0.5 U
MW-121B
0.5 U
0.5 U
0.5 U
0.5 U
MW-121C
0.33 J
0.5 U
0.5 U
0.5 U
Notes:
(a) "J" following value indicates that the analyte was detected at the concentration shown, but that the value was greater than the laboratory
method detection limit and less than the laboratory practical quantitation limit.
"U" following value indicates that the analyte was not detected above the laboratory practical quantitation limit indicated.
(b) Boldface type indicates that the analyte was detected above the method detection limit and represents a valid detection.
Abbreviations:
ug/L = micrograms per liter TCE = trichloroethene VC =
cis-1,2-DCE = cis-1,2-dichloroethene vinyl chloride
PCE = tetrachlorethene
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
Figures
-------
-------
EASTERN TRIBUTARY
CONCEPTUAL MODEL
—CHEI
MPLEX FACILITY LOCATION
WESTERN TRIBUTARY
= -5 -t OVERBURDEN , T* -~_» \| ^ JT ^
MAQUOKETA FORMATION (SHALE)
N
Legend:
s
©
O
2000 4000
(Approximate Scale in Feet)
Arrow indicates the direction of Groundwater
Flow (its size is proportional to the magnitude
of Groundwater Flow)
Creek Bottom Sediments
Sand Deposits
Silt/Clay Deposits
Two-Headed Arrow indicates Flow Direction
Changes throughout year.
Notes:
1. AH locations are approximate.
2. All dimensions shown are NOT to scale.
3. Groundwater flow directions and magnitudes may vary
depending upon rainfall infiltration rates.
Erler &
Kalinowski, Inc.
Conceptual Model
Chemplex Site
Clinton, Iowa
December 2013
EKI 890052.73
Figure 2
-------
-------
N
1000
2000
(Approximate Scale in Feet)
Legend:
• •••••••• Municipal Water System Extension
Area of ACC/GCC Environmental Covenant
Area of Equlstar Environmental Covenant
Area of Crossroads Environmental Covenant
Area of Camanche Ordinance
Erler &
Kalinowski, Inc.
Environmental Covenants and
Ordinance Area Boundaries
Chemplex Site. First OU
Clinton. Iowa
December 2013
EKI 890052.73
Figure 4
-------
-------
November 2013 PCE Concentration Less
than 10 Mflrt-
Notes:
1. All locations are approximate.
2. Groundwater extraction from this stratum began
•!r anc4M*.f5 in December 1994 and was suspended on
29 September 2008
MW-122A
2
5
o
5
i
|
>
n
I
<0 5
*0 5
<0 5
<0 5
<0 5
<0 5
MW-121A
_
5
|
i
1
<0 5
<0 5
<0 5
<0 5
<0 5
<05
MW-120A
ft
g
o
o
-
5
ii
l
|
5
§
s
$
5
s
<05
<0 5
<0 bl<0 5
<0 5
<0 5
<0 5
<0 5
<0 5
<05
MW-119A
1
S
1
a
I
|
o
S
9
£
i
1
2
s
CM
I
o
£
rt
5
0 79
0 48
069
W32
ow
11
1
11
1 2
1 3
1 0
1 2/1 1
er
Erler &
Kalinowski, Inc.
PCE Concentrations (ug/L)
Detected in Groundwater Samples
from Overburden Through 2013
Chempiex Site First OU
Clinton. Iowa
March 2014
EKI 890052.73
Figure 6
-------
/
/
ww-its
*• r -
WEST
REGIONU~-»
OCT' *
EW-3a
f
|
o
5
1
1
I
I
5 300
8 100
200
40
81
65
24
UN- 'Ml
¦ <»—
UL
EAST
REGION
TfJ
MW-18B
1
1
i
*
II
I
e
s
I
I
1
i
in
i
n
i
2700
<5
<5
<& *
4 MHM ^
T
V
58-J
> IW4H
.
V
oc-xa
MW-97A
I
I
1
a
1
f
s
s
A
©
5
§
1
j;
I
I
1
2
*
0 18
1 5
23
082
086
054
38
4 1
2.0
48
45
15
80
25
RX
*
* ~
KMII
* K-M
- f w
oo-aa
I . _ ow
L ,~
¦
cw-ti
HAWKtYt RO*D
EW-7a
?
«5
£
1
|
1
1
5
t
s
i
s
8
5
I
1
1
I
|
I
i
i
s
<1
74
110
150140
180
330
320
580
1000
1400
1800
1400
1400
1300
1100
900
1300
980
1000
t
MW-57-1
I
$
I
|
§
I
f I
!|
|
|
|
5
I
5
|
I
I
I
I
|
1
5
?
S
?
l
I
I
I
?
5
s
§
i
i
I
I
§
03
02
<1
12
<2
2
1
2
1
i
1
079
0 84/0 64
<0 5
069 1
1 1
14
0 87/0 86
089
0/1
0«
on..
.
I V.
16
22
20
40
36
46
N
~
500 1000
(Approximate Scale In Feet)
Legend:
Technical Impracticably Zone Boundary
•3r Monitoring Woi
¦ Former Extraction Well (Inactive)
¦ Former Extraction Well Injected with
Vegetable OH In July 2009
November 2013 PCE Concentration
Greater Than or Equal to 1.000 wg/L
November 2013 PCE Concentration
Between 100 and 1.000pg/L
November 2013 PCE Concentration
Between 10 and 100 pg/L
November 2013 PCE Concentration Less
than 10 \tQll
-
EW-11a
|
f
1
I
5
f
S
i
I!
I
o
|
a
1
1
1
1
A
£
324
38
41
86
140
150
120 144
160
77
41
63
93
90
100
Notes:
1. Ail locations are approximate.
2. Groundwater extraction from this stratum began
in February 1995 and was suspended on
29 September 2008.
Erler &
Kalinowski, Inc.
PCE Concentrations (ug/L)
Detected In Groundwater Samples From
Upper Scotch Grove Through 2013
Chemptox Site First OU
Clinton. Iowa
March 2014
EKI 890052.73
Figure 7
-------
\
\
s
MW-18C (3) _
2000
1
me
I
it
i
i
aoo
1
I
*400
I
I
MOO
s
utaiixa
5
5
«oc
WEST
REGION
\ WM-00-1
\ ~
\
V
• Ei
H
EAST
REGION
MW-82B (3)
I
l
1
I
1
1
1 II
I
1
5
I
I
Si
5
|
I
I
5
1
ISO
70
50
2d
iiefiiS
IOCV170jt20
130
110
120
1501150
160*150
180
150
1 A)
100
1«V730
N
MW-10RB (3
i
il
§
I
I
I
|
1
*
I
§
I
i
5
1
s
i
!
s
Si
s
S
5
s
§
1
1
|
i
§
Si
630
560
120
180
250*250
210210
m
411*300
430
34O~»0
<0 6
14
43
210
260
280
1U0
180
180
i«>
130
ew-i7»
~ IMk»
ijlimiuiujlui
iroj
trt ROAD
\ .
\
\
\
Ew-a*^ m
^ PT-4
"•
a
m
ii
E*M4« ¦ ~ ¦ Am-I1M •*;• MW-71-J ®
EW-1S*
MW-85B (3,
i
.5
§
S5
|
i
|
a
8
f
i
!
1
I
£
1
1
s
*L
T
•'Ui
in j_,
85 2755 Sebo
Lii.
ii
-lanssr
Ui
i
llj
[ [ 1
!i!
gg «0C
5 || | |
hhhspI
098 (3
! 111!
90&490 440 450 340 430 .
in
11
Li
•
i
iiiiu
MW-113A 3)
Ulffil
iiJ.ii
0 390 360' 360430 380 58
iii
o £6 55o it
1000
\
\ •*
MW-110BQ)
illllllllLllj
MW-1048 <3)
<0 5
<05
1
<0fi
|
"0 5
I
-0 5
?
§
"0 5
|
5
l
!
<0 5
?
5
<0 5
I
I
I
III! 11111ii i ill I III
T VI fj 1 i'\ 3f-o5 i1 8 ii jo 9*066 Ye o r?'o*«'oi>;|i at? s s_:
MW-117B
I
I
?
J)
I
i
1
I
<0S
*»N-X\9
~. -- ;
ARC
j—="
I
4
I
s
I
g
|
1
!
1
S
|
s
ai
i
<0 5
<0 »<0 5
<0 9
*6 s
<0 5
<0 5
0 51
<0 5
<0 5
<0 5
041
<0 5
/
MW-
22B
s
5
1
i
|
?
5
1
0 f:
<0 5
<05
<05
5
|
i
|
5
I
<0 5
<0 6
<05
<0 5
<0 5
<0 5
ARC MW-201B
I
§
§
f
§
1
5
1
1
5
5
e
i
|
1
i
uie
<0 5
-------
i
*
WEST
REGION
r-m
EAST
REGION
uu
Him
mm
S 2
5 S
MM
42 20 » 4
-III
Ills
20 19| 32
a
IlSi
3?|i 4*
i
42
11
4 38 S
i'i,
"-*« \
\
11 YE ROAD
MW-85C (31
!
1
Jl
|
1
1
1
*
5
5
5
1
1
?
I
1
s
5
|
1
§
1
I
04
'
*0 5
250
320
330
330
270
64
Mr,
87
<110
•25
MW-107C (31
I
a
I
|
f
|
I!
I
|
f
H
f
9
h
i
a
i
t
2
§
a
&
i
§
l
i
i
i
«
il
20
13
24
"
•»
it
14
18
•6
<9
22
29
24
24
\
WiMMM75T
I
= s
MIMII
I
\
III
MW-118C
I
a
!
I
|
a
i
i
£
*
I
<0 5
0 46
<64
<0 5
0W 3 045 «Oi 0 39 0 4.
ARC MW-200C (3
Mil
I
52 087 0
i
700*0
X
11
S 3 48 5 56
ARC MW201C
1
|
§
§
s
a
1
!
if
I
1
5
§
I
<0 4
*
|
I
i
a
a
I
<0 4
631
<05
<64
<0 5
<0 5
<0 5
<05
<66
MW-122C
o
o
. I
i
5
§
I I
1
<0 S«0 5
<0 Sf<0 5
<0 5
<06]«OS
<0 5
ARC MW-209BC
1
A
j
I
I
a
I
1
fli
i
1
I
i
§
s
0 75
—
MW-119C
I
!
I
n
m
1
1
i
f
0«
0 5M> 52
0 72
tt*l|l 4
I if' 6
J
24
•
i 9
N
~
500 1000
(Approximate Scale In Feet)
Legend:
— — Technical Impracticability Zone Boundary
4- Monitoring Well
¦ Former Extraction WeH (Inactive)
¦ Former Extraction Well Injected with
Vegetable Ol In July 2009
~ Monitoring Well Injected with
Lactate In October 2013
~ Monitoring WeH Injected with
Permanganate In October 2013
November 2013 PCE Concentration
Greater Than or Equal to 1.000 pg/L
November 2013 PCE Concentration
Between 100 and 1.000 pg/L
November 2013 PCE Concentration
Between 10 and 100 pg/L
^ November 2013 PCE Concentration
Less than 10 pg/L
Notes:
1. AD locations are approximate
2. Groundwater extraction from the Farmers
Creek stratum began in September 1995 and
was suspended on 8 November 2005.
3. Due to figure readability Issues, only data
since January 2002 are shown on this figure.
Please refer to previous samping reports for
data prior to January 2002.
4. The reported analytical data from wells
MW-107B and MW-107C for samples
collected on 28 October 2004 are suspected to
be switched. The shown concentration is as
reported by the laboratory.
Erler &
Kalinowski, Inc.
PCE Concentrations (ug/L)
Detected in Groundwater Samples
From Farmers Creek Through 2013
Chemptex Site First OU
Clnton. Iowa
March 2014
EKI 890052.73
Figure 9
-------
1
WEST
EAST
REGION
REGION
\
\
\
\
c \
^ p''
¦rT-'a
Ti
4.YL ROAD
~ l
\
\
\
\
filliillil
Sii!
5 <05 7~6 10 <"
W-6c
ill
S 7
\Ll
Im'I
M
i -
i Si
2/5 0 4 1
X
\
A
\
X
\
V \
\
140/120
95 30
|
>
54o|530l610
N
~
500 1000
(Approximate Scale in Feet)
Legend:
— — Technical Impracticability Zone Boundary
^ Monitoring Well
¦ Former Extraction Well (Inactive)
November 2013 PCE Concentration
Greater Than or Equal to 1,000 pgA.
November 2013 PCE Concentration
Between 100 and 1.000 pg/L
November 2013 PCE Concentration
Between 10 and 100 pg/L
November 2013 PCE Concentration
Less than 10 pg/l
luiuimui
11
raoir
S 5
<0 5 <0 5 <0 5
- oi n
i i
b <05 04fl <05
T
y
\
ARC MW-200D
I
I
f
$
I
5
§
1
i
i
IN
i
r>
§
«•»
|
<05
<05
025
<0.5
0 28
<05
<0 5
<0 5/<0 5
0 36/<0 5
035
040
<0 5/0 31
03
Notes:
1, Afl locations are approximate.
2. Groundwater extraction from this stratum
began on 18 November 1995 and was
suspended on 17 March 1999.
Erler &
Kalinowski, Inc.
PCE Concentrations (ug/L)
Detected in Groundwater Samples
From Lower Hopkinton Through 2013
Chempiex Site First OU
CHnton. Iowa
March 2014
EKI 890052.73
Figure 10
-------
WEST
REGION
MW-70
I
I
i
§
s
a
1
1
o
>
5
i
I
I
<5
-------
EASTERN UN-NAMED
TRIBUTARY ("EAST TRIB")
N
~
(Approximate Scale In Feet)
Legend:
• Surface Water Sample
November 2013 PCE Concentration
Greater Than or Equal to 1 000 pg/L
A November 2013 PCE Concentration
Between 100 and 1,000 pgl.
November 2013 PCE Concentration
Between 10 and 100 pg/L
November 2013 PCE Concentration
Less than 10 pg/L
Chemple* Site First OU
Clnton, Iowa
March 2014
EKI 890052.73
Figure 12
-------
WEST
REGION
MW-18C (LSG)
I Compound
I tOiMweUwO
I
I
n
I
I
a
|
|
s
i
S
§
I
5
s
MO
1X0
ai'jtj
'00
180
m
22C
200
Ho
88
m
1000/1100
:MC
"
-
L'hi.-,
m
2100
2300
~-*x;
•«oc
"¦900
210QT2100
LMl)
TCE (5) «
II
4 e
i !
2B/28 3
ll
¦4-1
I 1
5
7 18
li
7 17 7
© o
5 1
; is 2
ii
20
si
19
III
10 26 35
\
\
i
\y
RMct
UKWKVft— WOAO
4
\
J
DO-21C (LSG)
MW-107A
*
MW'M* MM-W7A
(ClMnup
LWI
I
I
1
1
I
A
1
S
I
1
$
1
5
1
S
2
5
o
s
£
1
1
Si
1
I
§
TCE (5)
<1 9
<2
<01
<1
34
06
22
t
19
17
2
2
26
38
32
42
5
63
57
83
MW-53A (OVB)
Ccmptxrd
(ClMnup
L.««>
f
f
0
1
ii
S
5
i
§
5
§
1
jo
TCE (5,
<5
<5
92/94
78
72
97
10
13/14
16
15
3 (OVB)
Campastd
(ClMnup
|
|
I
|
1
|
I
1
1
!
I
5
I
I
I
s
1
a
1
5
|
1
f
1
|
|
o
o
|
I
5
1
i
*
"3
1/<5
1 2/<0 l/<0 1
-------
Monitoring Wei Injected with Lactate or
Vegetable Oil In October 2013
Monitoring Wei Injected with
Permanganate in October 2013
Emm « «nnn« Bii n »,n ¦t;nrn>:ir.m:ii inn iiiir
-------
N
500 1.000
(Approximate Scale in Feet)
- . Leoend:
'880.
(637.65)
Upper Scotch Grove Extraction Weil
Upper Scotch Grove Monitonng Well
Lower Scotch Grove or Picture Rock
Monitonng Well
Groundwater Elevation Contour
in Feet Above Mean Sea Level
Groundwater Elevation in Feel
Above Mean Sea Level Measured
in Wells on 18 November 2013
Notes:
1. All locations are approximate.
2. Contour Interval 5 feet.
3. On 29 September 2008. groundwater extraction in the
Upper Scotch Grove Unit was discontinued
4. Some wells displayed are screened in underlying or
ovedying formations, as indicated by the well symbols.
5. Groundwater elevations marked wrth a greater-than sign
(>) were artesian or flowing artesian on the date of
measurement
Erler &
Kalinowski, Inc.
Upper Scotch Grove Formation
November 2013 Potentiometric Surface
Chemplex Site. Rrst OU
Clinton, IA
January 2014
EKI 890052.64
Figure 14
-------
N
~
500 1.000
(Approximate Scale in Feet)
- Legend:
¦ Upper Scotch Grove Extraction Well
* Lower Scotch Grove Monitoring Well
* Upper Scotch Grove Morotonng Well
w Picture Rock Monitoring Well
^ Groundwater Elevation Contour
^ in Feet Above Mean Sea Level
Groundwater Elevation in Feet
(637.65) Above Mean Sea Level. Measured
in Wells on 18 November 2013
Notes:
1. All locations are approximate.
2. Contour Interval: 5 feet.
3. On 29 September 2008. groundwater extraction in the
Upper Scotch Grove Unit was discontinued.
4. Some wells displayed are screened in underlying or
overlying formations, as indicated by the well symbols.
5. Groundwater elevations marked with a greater-than sign
(>) were artesian or flowing artesian on the date of
measurement.
Erler &
Kalinowski, Inc.
Lower Scotch Grove Formation
November 2013 Potentiometric Surface
Chemplex Site, First OU
Clinton, IA
January 2014
EKt 890052.64
Figure 15
-------
-AVENUE
(644.58)
MW-80C^
Legend:
4TH avkmi;
;
* MW-82C
(628.59)
¦EW-13b
(618.01)
EW-6b ¦
(620.26)
HAU'KEYE
HOAD
(614.31)
MW-73-1
(615.53)
MW-101C
¦ ~ (6-14J5)
, j PT/RW=3
MW-84C
(622.03)
¦ EW-11b
(607.95)
* MW-103C /
(606.6)
-------
Notes:
1, Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-13C and
Picture Rock well MW-13D. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
West Region Monitoring Well Pair
MW-13C/MW-13D
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 17
-------
4.00
3.00
2.00
1.00
0.00
V
2 -1.00
I
a
I -2.00
-3.00
-4.00
-5.00
-6.00
§E.§£.§£.D)£.a>E.§£.g>c:a)coiccu
V
*
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-18C and
Farmers Creek well MW-18F. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
9}£.3j&.S»c_g>c»cj»cttcg>cpc
gS°2sS°SgSo°ggg°og
Date
E. § E. &> E. fi> S.
Erler &
Kalinowski, Inc.
Historic Head Difference in
West Region Monitoring Well Pair
MW-18C/MW-18F
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 18
-------
4.00
2.00
0.00 •
-2.00 •
£
Q
"O
s
x
-4.00 ¦
-6.00
-8.00 ¦
\
!P
I
8
I !?
$ =r
51
"o o
13
(0
Mill
Nfiies:
1. Head difference shown is the difference
between the groundwater elevation at
Upper Scotch Grove well MW-26C and
Picture Rock well MW-26E. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
CBCGJCCDCQJCOJCBl
3-T3T3T3— 3T 3
3 T- = r 3
5 ^ S S &
• C_C_C_C_C_C_C_C_;_C_ c_t_c_t_c_i_
.§E.2j£.2}£.®E.9jE.®E.9JE.9>£L
r 3 r-
^ ^ w
Date
Erler &
Kalinowski, Inc.
Historic Head Difference in
West Region Monitoring Well Pair
MW-26C/MW-26E
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 19
-------
2.00
0.00
-2.00
-4.00 ¦ —
-6.00 —
f -8.00
1
o
n -10.00
Q>
-12.00
-14.00
-16.00
-18.00
4— *
r —~
!'
Pf ^
~
i
s!
Qi
a ;
i o
:
3 :
3
3 i
•
71
^ s
• CT
¦ O
: 3
i 2.
3 j
<
if
' Q) _
:
j
j
4
V
3:
3
3
: O
i 3
• c
: 3
: °-
: *
to
7C
CD ;
1 ;
j 3
: a
: o
: 3
-I 3
! &
: o
: 3
! 3
J 3 -
i
3
J
3
1 ^
i i
1 8
(/>
• 3
• I-
: o
: S
J a>
; r~
: °
S
: ®
: i
•
¦
j
3
~>
5
T>
JT
~t CD
i ^
: cn
: •<
• u>
J. (D
; I
: o
i "P
i ro
: a>
: tj
i w
: c
• w
: T)
T
:
;
.
!
|
A
A
3
|
; 3
i co
: c
• (O
: T3
: ®
I 5
: w>
• 3
: a.
: a»
; o.
j 1
|
*
: o.
; a>
: Q-
! i
o a
t_
c
c_
0)
t_
c
t_
0)
t_
c
c_
0)
c_
c
o
CO
o
o
¦*>»
6
Oi
o
cn
o
O)
o
O)
Date
5 I
O ' -k ' '
® S ° i - M
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-27C and
Farmers Creek well MW-27E. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
West Region Monitoring Well Pair
M W-27 C/MW-27E
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 20
-------
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-71-1 and
Lower Hopkinton well MW-71. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
West Region Monitoring Well Pair
MW-71-1/MW-71
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 21
-------
-0.50
Date
Nfitgs,
1. Head difference shown is the difference
between the groundwater elevation at
Picture Rock well MW-64-1 and Blanding
well MW-64. A positive head difference
indicates an upward vertical gradient, while
a negative head difference indicates a
downward vertical gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
East Region Monitoring Well Pair
MW-64-1/MW-64
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 22
-------
0.00
-2.00
-10.00
-12.00
-14.00
s
>
1
;
\
>
§ E § E S> E
SSjSjS
§E§E§E9jE§E§E§E§E§E§E§E§E
®SgSg8o°o°oSgSo°g§g3gggg
Date
§ E § E
Notes;
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-65-1 and
Blanding well MW-65. A positive head
difference indicates an upward vertical
gradient, while a negative head difference
indicates a downward vertical gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
East Region Monitoring Well Pair
MW-65-1/MW-65
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 23
I
-------
1.00
0.00
-1.00
f
— -2.00
CD
<8
m
I
3
I
o
£
i
a
-3.00
V<-
A
\
-4.00
-5.00
-6.00
J
11
y
/
i
/
• •
ft.
o
5 3
CL 9}
i 3
Q- = ¦
fl>
3
o
4
1
CO 3
la
»o
CO C
C 3
"a 9-
§ S
Q. CD
C 0) C 01 c
O o
0) C 0>
— T 3
O ^
° 1*
C CD
— 3
N>
Date
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-82B and
Fanners Creek well MW-82C. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
2. Head differences for First, Second,
Third, and Fourth Quarters 2005, and First
and Second Quarters 2006 are unavailable
as Well MW-82B was not gauged due to an
obstruction in the well.
Erler &
Kalinowski, Inc.
Historic Head Difference in
East Region Monitoring Well Pair
MW-82B/MW-82C
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 24
-------
-1.00
-3.00
-5.00
-7.00
£
I
Q
1 -9.00
-11.00
-13.00
-15.00
§S.§S.§E§E.gEgE.g
Date
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-83B and
Farmers Creek well MW-83C. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
East Region Monitoring Well Pair
MW-83B/MW-83C
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 25
-------
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-84B and
Farmers Creek well MW-84C. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
East Region Monitoring Well Pair
MW-84B/MW-84C
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 26
-------
10.00
-20.00
O J J J J
C Q> C Q> C
_ _j _ _ _
ro
CO
Date
Notes.
1. Head difference shown is the difference
between the groundwater elevation at
Upper Scotch Grove well MW-106A and
Farmers Creek well MW-106C. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
2. An uncharacteristically large upward
gradient was observed during the Third
Quarter 2006 gauging event on
1 August 2006. Causes for this spike were
unknown. Water levels were measured
again in October 2006. The large upward
gradient was unconfirmed.
Erler &
Kalinowski, Inc.
Historic Head Difference in
East Region Monitoring Well Pair
MW-106A/MW-106C
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 27
-------
0.00
-2.00
Date
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Lower Scotch Grove well MW-109B and
Farmers Creek well MW-109C. A positive
head difference indicates an upward
vertical gradient, while a negative head
difference indicates a downward vertical
gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
East Region Monitoring Well Pair
MW-109B/MW-109C
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 28
-------
o
"O
£
x
3.00
2.50
2.00
1.50
1.00
0.50
0.00
-0.50
-1.00
%
Q)
ft
3
o
3
(i
5
o
si
~. ro
(D -«
(D
V
E.§E.§E.§E.§E.§£.gE.§S.§£.§E8>E.gE.®£.!»E.§S.§
2sSsSsSsSgSi5gSggggo2oSoBgSggg
Date
CgCttCttCBCjUCfiJCgJC
Ss3a§sS^o-;ir;f3r;u
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Farmers Creek well MW-101C and Lower
Hopkinton well MW-101D. A positive head
difference indicates an upward vertical
gradient, while a negative head difference
indicates a downward vertical gradient.
/
Erler &
Kalinowski, Inc.
Historic Head Difference in
West Region Monitoring Well Pair
MW-101C/MW-101D
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 29
-------
0.30
0.20
0.10
0.00
-0.10
-0.20
-0.30
-0.40
7V
cgjcwcttcwca
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Farmers Creek well MW-97C and Lower
Hopkinton well MW-97D. A positive head
difference indicates an upward vertical
gradient, while a negative head difference
indicates a downward vertical gradient.
8 8 2 S § S j ^ f
Date
Erler &
Kalinowski, Inc.
Historic Head Difference in
West Region Monitoring Well Pair
MW-97C/MW-97D
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 30
-------
20.00
0.00
-20.00
-40.00
-60.00
-80.00
-100.00
-120.00
-140.00
I1"
3
s
®
I
o
a
a
n
1
J L
1
Q) C 0) C
CO)CD>CQ)CQ)C
S 2 "
0) C 0)
T A T
o 9 o
^ r n
3 T 3 T
0) C 0) C Q>
3 T 3 T 3
O ° M
Date
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Farmers Creek well MW-84C and the
adjacent Lower Hopkinton well EW-14c. A
positive head difference indicates an
upward vertical gradient, while a negative
head difference indicates a downward
vertical gradient.
Erler &
Kalinowski, Inc.
Historic Head Difference in
Adjacent East Region Wells
MW-84C/EW-14c
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 31
-------
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Farmers Creek well MW-85C and the
adjacent Lower Hopkinton well EW-15c. A
positive head difference indicates an
upward vertical gradient, while a negative
head difference indicates a downward
vertical gradient.
2. The head difference for 30 August 2007
was not calculated because Well MW-85C
was obstructed at six feet below the ground
surface and the water level in this well was
therefore not measured.
Erler &
Kalinowski, Inc.
Historic Head Difference in
Adjacent East Region Wells
MW-85C/EW-15c
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 32
-------
Notes:
1. Head difference shown is the difference
between the groundwater elevation at
Farmers Creek well
MW-108C and the adjacent Lower
Hopkinton well EW-16c. A positive head
difference indicates an upward vertical
gradient, while a negative head difference
indicates a downward vertical gradient.
2. The pump at inactive extraction well
EW-16c was exercised on 28 August 2003,
temporarily causing an uncharacteristically
large downward gradient. As a result, the
head difference shown for August 28 on this
figure does not represent the ambient head
difference between wells
MW-108 and EW-16c.
Erler &
Kalinowski, Inc.
Historic Head Difference in
Adjacent East Region Wells
MW-108C/EW-16c
Chemplex Site
Clinton, Iowa
March 2014
EKI 890052.73
Figure 33
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
Appendix A
Inspection Checklist
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site — Clinton, Iowa
OM'ERNv. 9355 7-03B-P
Please note that "O&M" is: referred to throughout this checklist. At sites where Long-Term
Response Actions are in progress, O&M activities may beireferred to as "system operations" since
these sites are not considered to be in the O&M phase while being remediated under the Superfund
program.
Five-Year Review Site Inspection Checklist (Template)
(Working document for site inspection. Information may be completed by hand arid attached to the
Five-Year Review report as supporting documentation of site status. "N/A" refers to "not applicable:")
I. SITE INFORMATION
32
Site name
Date or inspection:
Location and Region:
Agency, office, or company leading the five-year
review: £PA s
Weather/temperature:
Q-Pc/KQnri r-JJ 3b°-fr
Remedy Includes: (Check all thai apply)
/""Landfill cover/containment M^onitbred natural attenuation
/^Access controls • Groundwater containment
tMtfstitutional controls Vertical banner walls
Groundwater pump and treatment -
Surface water collection and treatment
Other . . ... . .
Attachments: Inspection team rosier attached
Site map attached
II. INTERVIEWS (Check all that apply)
inagerVjgL^W^TTWP/Wgf- dpef&fatK AhigCPT- Tl/i3/-2dl3
^ Name ' Title Date
Cat sit?) at office by phone Phone ho. -5o
1. O&M site manager
Name
Interviewed (at s"t?) at office by phone Phone ho
Problems, suggestions; Report attached
2. O&M staff.
Name Title
Interviewed at site at office by phone Phone no.
Problems, suggestions; Report attached
Date
D-7 l
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site — Clinton, Iowa
OSWERNo. 9355.7-03B-P
3. Local regulator}' authorities and response agencies (i.e., Slate and Tribal offices, emergency
response office, police department, office of public health or environmental health, zoning office,
recorder of deeds, or other city and county offices, etc.) Fill in all that apply.
Name / title . ¦ Date . Phorie.no.
Problems; suggestions; Report attached ACCf£XjC^M*>ritJy tM&h rflfSr-Jl,"
mrnm
Name Title Date Phone no.
Problems; suggestions; Report attached
Agency ,
Contact
Name Title Date Phone no.
Problems; suggestions; Report attached .
Agency
Contact
Name Title Dajc Phone no.
Problems; suggestions; Report attached .
4. Other interviews (optional) Report attached,
D-8
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSWER No. 9355. 7-03B-P
III. ON-SITE DOCUMENTS & RECORDS VERIFIED (Check all that apply)
O&M Documents
O&M manual Readily available Up to date N/A
As-built drawings Readily available Up to date N/A
Maintenance logs^ Readily avail^lc Up to date N'A , .
Remarks -Sl> u4y--fe?f<)h A-l^Tlfl Gtun^oiVg
Site-Specific Health and Safety Plan Readily available Up to date N'A
Contingency plan/emergency response plan Readily available „ Uptadata N/A
R^i^arks^^^rii [ fA & HjA- L^\"i^Cacx , i J
-Ru j^avot ,g£frgs- -fe
Gas Generation Records Readily available Up to date (N'A
Remarks :
6. Settlement Monument Records Rcadiiy available Up to date (Tvj7A~?
Remarks : ¦ .
7. Groundwater Monitoring Records r Rcadiiy available Up to date (N/A J
Remarks AA Lt)Hy
8. Leachate Extraction Records ¦. Rcadiiy available Up to date N/A
Remarks .
Discharge Compliance Records
Air Readily available Up to diitc N/A
Up to;da(c N'A
Remarks.
9/^r
10. Daily Access/Security Logs Readily available Up to date
Remarks . . . .
D-9
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSWERNo. 935S.7-03B-P
IV. O&M COSTS
O&M Organization
State in-house Contractor for Stale
Is&kp in-housc C"5ontractor for
Federal Facility in-house Contractor for Federal Facility
0lher/O<«=»-
O&M Cost Records ( >njz>
Readily available Up to date
Funding mechanism/agreement in place
Original O&M cost estimate Breakdown attached
Total annual cost by year for review period if available
From
To
Breakdown
attached
Date
Daic
Total cost
From
To
Breakdown
attached
Date
Date
Total cost
From
To
Breakdown
attached
Date
Date
Total cost
From
To
•Breakdown
attached
Date
Date
Total cost
From
To
Breakdown
attached
Date
Dale
Total cost
3. Unanticipated or Unusually High O&M Costs During Review Period
Describe costs and.reasons:
V. ACCESS AND. INSTITUTIONAL CONTROLS C^pi^abic^) N.'A
A. Fencing
I. Fencing dayn^ged t Location shown oh site niap Gates secured N/A
~>-Q
Fencing damaged . Lo
Remarks /f_
B. Other Access Restrictions
I. Signs and^)ther securitjL.measures . Location.shown on site map N/A
D-10
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSWER No. 93SS.7-03B-P
C. Institution*! Controls (JCs)
Implementation and enforcement
Site conditions imply ICs not properly implemented ~
Site conditions imply ICs not being fully enforced
Type of monitoring(e.g., self-reporting, drive bv)^
?e£Iliracy Ji£3=faiaag^gt-- cto/c
Responsible mrty/agen
ConlaclVl?>
Name " Title "
Yes C© N/A
Yes <5lP N/A
Date Phone no
Reporting is up-to-date
Reports are verified by ihe lead agency jpS N/A
fYB/ No N/A
Specific requirements in deed or decision document! have been met No
Violations have het>n runnri>(0
Violations have been reported
|t|erprob|emsiMiiggestions: f Report aP^che:
N/A
Yes No OW
„ ®naMsm/tresjassing f Location ^ioot. pn site map No vandalism evident
Retnarks_4i»2-a*/j r^-sr-jc fc-rZJh+~,
jig
o
Laid use changes off site
Remarks
VI. GENERAL SITE CONDITIONS
A. Roads
N/A
R=«rksJ£iNA
\F
D-it
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSWER No. 9JJJ. 7-Q3B-P
B. Other Site Conditions
Remarks
VII. LANDFILL COVERS f^gpgiTcablc^ N/A
A.
Landfill Surface
1. Settlement (Low spots) Location shown on site map ^""Settlement not evident
Areal extent Depth / / PV fl
Remarks /"frC^gfer h(Yi=z£
2.
Cracks Location shown on site map ^Crackiricnot evideti^
Lenpths Widths DcDths
Remarks
3.
Erosion Location shown on site map Erosion not evident
Remarks <£*=> 7#=-/, l( jJcxftS
tkj
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSH'F.R Nu 9355.7-01B-P
8.
Wet Areas/Water Da mace areas/w^ter damape not evidenTT
Wet areas Location snown on site map Areal extent
Pondinc Location shown on site map Areal extent
SeeDS Location shown on site man Areal extent
Soft suberade Location shown on site maD Areal extent
Remarks
9,
Slope Instability
Areal extent
Remarks
Slides Location shown on site map X*No evidence of slope instability""}
B.
Benches Applicable
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSIVER No, 9S55.7-03B-P
4.
Undercutting Location shown on site map <^^No^evidence of undercutting)
A real extent Depth
Remarks
5.
Obstructions Tvpe
Location shown on site map
Size
Remarks
^iis>_6bstnictions y
Areail extent
6.
Excessive Veeetative Growth Tvne
r—-NcTevidence of excessive ero\ftlT5
Vegetation in channels does not obstruct flow
Locution shown on site map Areal extent
Remarks
D.
Cover Penetrations c—^pplicabltT~) N/A
All
1. Gas Vents Active Passive
Properly secured/locked Functioning Routinely sampled Good condition
Evidence of leakage at penetration Needs Maintenance
Remarks firl f^pC?raJ-^Q <7^7 CI Ucr f ^7
2.
Gas Monitoring Probes
Properly secured/locked Functioning
Evidence of leakage at penetration
Remarks
Routinely sampled <^Qood condition J
Needs Maintenance FJ7A
3'.
Monitoring Wells (within surface area of landfill)
Properly secured/locked Functioning Routinely sampled c"uood condition^
Evidence of leakage at penetration Needs Maintenance ' N/A
Remarks
4.
Leacirffe^Extraction Wells
(^Properly secured/loc1
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OS\VERNi>.9355.7-0}BrP
D-15
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSWERNo. 9S55.7-03B-P
H. Retaining Walls
I. Deformations Location shown on site map Deformation not evident
Horizontal displacement Vertical displacement
Rotational displacement
Remarks
2. Degradation
Remarks
Location shown on site map Degradation not evident
I. Perimeter Ditches/OfT-Site Discharge Applicable (fri/A^-
I. Siltation
Area! extent_
Remarks
Location shown on site map Sijtation not evident
Depth
Vegetative Growth Location shown on site map N/A
Vegetation does not impede flow
A real extent Type
Remarks
Erosion
Area] extent_
Remarks
Location shown on site map
_ Depth ¦
Erosion not evident
Discharge Structure
Remarks
Functioning N/A
VIII. VERTICAL BARRIER WALLS Applicable QWA
Settlement
Arcal extent_
Remarks
Location shown on site map Settlement not evident
_ Depth
Performance MoriitoringType of moriitoring_
Performance not monitored
Frequency
Head differential ;
Remarks ;
Evidence of brcachiric
D-16
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site — Clinton, Iowa
IX. groundwatkr/surface water remei
A^GroiMdwatef Eitractloa Wells, Pumps, tnd Pipelin
OSWERNo. 9355J-Q3B-P
^ N/A
Pu™P*» WeHheai Plumbing, and Electrical
~ "V •' t i J; tLJoiJlA
Spare Parts rnid-Egutpn...,!
CI«gikiaiiable \
Requires upgrade Needs to be provided
Collection Structures, Pumps, and Electrical
Good condition Needs Mainfc
flection System Pipeline!, Valves, Valve Bov« »„rf n.K a
Good condition Needs Maintenance Appurtenances
Remarks
D-17
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSU'ER No. 9355.7-03B-P
Applicable N/A tsfeoA
C. Treatment System
Treatment Train (Check components that apply)
Metals removal Oil/water separatipn
Air stripping Carbon adsorbers
Filters
Biorcmediation
Additive (e.g., chelation agent. flocculent)_
Others .
Good condition Needs Maintenance
l^Sampling ports properly marked and functional
(^5ampling/maintenance log displayed and up to date
/~-Equipment properly identified _ f/l f
Quantity of groundwater treated annually I
Quantity of surface water treated annually^
Remarks
V
2. Electrical Fnrlntiirpi; and Pa nek (nrnperlvratpri and functional)
N/A £"Good condition)
Remarks 1
Needs Maintenance
Tanks, Vaults, Storage Vessels ¦
N/A f Oobifconditioir^ CPrnpi-r cprnnHnry rnniaifTmcnb Needs Maintenance
Remarks '
4.
Discharge Structur^and^ppuiUeaances
N/A /^GoOd condition '_J .............
Remarksh<&fr~sd'C£iT~
eeds Maintenance
Treatment Building(s)
NM
^Chemicals £
Needs repair
CGood condition jfesp. roof and doorways)
micals and equipment properly stored 1 r\ if) H
¦¦¦—ks
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
OSIVER No. 935x 7-03B-P
D. Monitored Natural Attenuation
Mnnltftrinp Wallt-(natural attenuation remedy)
Properly secured/locked Functioning d]Routinely sampiccl) ^"Good condition
All required wells Located Needs Maintenance ,j /-j N/A
RemarkC, izLls t f-
X. OTHER REMEDIES
If there are remedies applied at the site which are not covered above, attach an inspection sheet describing
the physical nature and condition of any facility associated with the remedy. An example would be soil
vapor extraction.
XI. OVERALL OBSERVATIONS
A. Implementation of the Remedy
Describe issues and observations relating to whether the remedy is effective and functioning as
designed. Begin with a brief statement of what the remedy is to accomplish (i.e., to contain contaminant
plume, minimize infiltration and gas emission, etc.).
B. Adequacy of O&M
Describe issues and observations related to the implementation and scope of O&M procedures. In
particular, discuss their relationship to the current and long-term protccliveness of the remedy.
D-19
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site — Clinton, Iowa
OSII'ER No: 9355.7-D3B-P
C. Early. Indicators of Potential Remedy Problems
Describe issues and observations such as unexpected changes in the cost or scope of O&M or a high
frequency of unscheduled repairs, that suggest that the protectivcness of the remedy may be
compromised in the future.
D. Opportunities for Optimization
Describe possible opportunities for optimization in monitoring tasks or the operation of the remedy.
D-20
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
Appendix B
Inspection Photographs
-------
FOURTH FIVE-YEAR REVIEW REPORT
Chemplex Site - Clinton, Iowa
List of Pictures:
Waterline Location
1. 9th Street facing west
2. 31st Street facing north
3. City Hall water tower
4. Highway 67 water tower
Landfill Area
5. Landfill 1 - Entrance facing north
6. Landfill 2 - Entrance to NS access facing north
7. Landfill 3 - Upper area facing east
8. Landfill 4 - Upper area facing north
9. Landfill 5 - LF-6 facing west
10. Landfill 6 - MW-7 facing south
-------
Photo#!
Description: 9th Street facing west
Date: 13-Nov-13
Site: Chemplex Company, Clinton, Iowa
-------
-------
Photo #5
Description: Entrance facing north
Date
Site: Chemplex Company, Clinton, Iowa
Photo #6
Description: Entrance to NS access facing north
Date
Site: Chemplex Company, Clinton, Iowa
-------
Photo #7
Description: Upper area facing east
Date: 13-Nov-13
Site: Cheniplex Company, Clinton, Iowa
Photo m
Description: Upper area facing north
Date: 13-Nov-13
Site: Chemplex Company, Clinton, Iowa
-------
Photo #9
13-Nov-13
Description: LF-6 facing west
Site: Chemplex Company, Clinton, Iowa
Photo #10
Date: 13-Nov-13
Chemplex Company, Clinton, Iowa
MW-7 facing south
------- |