U.S. ENVIRONMENTAL PROTECTION AGENCY 

OFFICE OF INSPECTOR GENERAL 

Catalyst for Improving the Environment 

 Evaluation Report 

EPA Should Improve Its 

Oversight of Long-Term 

 Monitoring at Wheeling Disposal 

 Superfund Site in Missouri 

Report No. 11-P-0034 

 December 20, 2010 
 

Report Contributors: Carolyn Copper 

 Patrick Milligan 

 Martha Chang 

 Anne Bavuso 

Abbreviations 

CFR Code of Federal Regulations 

EDB 1,2-Dibromoethane 

EPA U.S. Environmental Protection Agency 

mg/L Milligrams per Liter 

NPL National Priorities List 

O&M Operation and Maintenance 

OIG Office of Inspector General 

ROD Record of Decision 

RP Responsible Party 

TDS Total Dissolved Solids 

μg/L Micrograms per Liter 

VOC Volatile Organic Compound 

Cover photo:	 Signage on barbed wire fence surrounding Wheeling Disposal Superfund Site, 

near Amazonia, Missouri, December 12, 2007. (EPA OIG photo) 
 

 

 

 

 

U.S. Environmental Protection Agency 11-P-0034 

December 20, 2010 Office of Inspector General 

At a Glance 

Catalyst for Improving the Environment 

Why We Did This Review 

The Office of Inspector 

General is testing long-term 

monitoring results at 

Superfund sites the U.S. 

Environmental Protection 

Agency (EPA) has deleted 

from the National Priorities 

List. The Wheeling Disposal 

Superfund Site, located near 

Amazonia, Missouri, in EPA 

Region 7, is one of eight sites 

reviewed. 

Background 

Wheeling Disposal is a 

landfill that received 

hazardous wastes, including 

leather tanning sludges, 

pesticides, asbestos, 

laboratory wastes, paint 

sludges, battery wastes, and 

cyanide wastes. The site was 

added to the National 

Priorities List in 1989 and 

deleted in 2000 when EPA 

determined that cleanup goals 

had been achieved. 

For further information, 

contact our Office of 

Congressional, Public Affairs 

and Management at 

(202) 566-2391. 

To view the full report, 

click on the following link: 

www.epa.gov/oig/reports/2011/ 

20101220-11-P-0034.pdf 

EPA Should Improve Its Oversight of Long-Term 

Monitoring at Wheeling Disposal Superfund Site 

in Missouri 

What We Found 

Our independent sampling results from the Wheeling Disposal Superfund Site were 

generally consistent with the sampling data that Region 7 has obtained historically. 

However, when the responsible parties reported their annual monitoring results, 

Region 7 inadvertently allowed them to use incorrect and outdated surface water 

standards, and outdated ground water standards. Also, Region 7 did not always 

require the responsible parties’ laboratories to properly analyze some contaminants. 

By allowing incorrect standards and analysis methods, the region has limited 

assurance that unsafe levels of contaminants are not migrating offsite and creating 

risk to human health and the environment. These issues do not adversely impact the 

region’s current protectiveness determination. However, if incorrect and outdated 

standards continue to be used, or results are not properly analyzed, the region may 

be unable to detect when excess levels of contaminants migrate offsite. 

In a 2009 report, Region 7 should have explained the impact of excess levels of 

iron and aluminum at sampling locations close to the site boundaries. EPA records 

describe the site as a “habitat for wildlife and birds.” However, the region had not 

addressed contaminants in the site’s surface water that can pose risks to ecological 

receptors. In response to Office of Inspector General inquiries and Agency 

guidance, in October 2010, the region completed an ecological risk assessment. The 

risk assessment showed that the remedy is protecting the environment. 

What We Recommend 

We recommend that the Region 7 Administrator ensure accurate surface water and 

ground water standards are used to assess conditions at the site; laboratories use the 

correct analytic standards; the ecological risk assessment is completed; and excess 

levels of iron, aluminum, and any other compounds are controlled at the site. 

Region 7 agreed with OIG recommendations and has initiated or completed some 

actions. 
 

 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

THE INSPECTOR GENERAL 

December 20, 2010 

MEMORANDUM 

SUBJECT:	 EPA Should Improve Its Oversight of Long-Term Monitoring at 

Wheeling Disposal Superfund Site in Missouri 

 Report No. 11-P-0034 

FROM: Arthur A. Elkins, Jr. 

 Inspector General 

TO: Karl Brooks 

 Region 7 Administrator 

This is our report on the subject evaluation conducted by the Office of Inspector General (OIG) 

of the U.S. Environmental Protection Agency (EPA). This report contains the findings from our 

sampling at the Wheeling Disposal Superfund Site and corrective actions the OIG recommends. 

EPA Region 7 concurred with and provided comments on the recommendations of the draft 

report. This report represents the opinion of the OIG and does not necessarily represent the final 

EPA position. Final determinations on matters in this report will be made by EPA managers in 

accordance with established resolution procedures. 

The estimated cost of this report, calculated by multiplying the project’s staff days by the 

applicable daily full cost billing rates in effect at the time, then adding in the contractor costs, is 

$654,653. 

Action Required 

In accordance with EPA Manual 2750, you are required to provide a written response to this 

report within 90 calendar days. Your response will be posted on the OIG’s public website, along 

with our comments on your response. Your response should be provided in an Adobe PDF file 

that complies with the accessibility requirements of section 508 of the Rehabilitation Act of 

1973, as amended. If your response contains data that you do not want to be released to the 

public, you should identify the data for redaction. You should include a corrective action plan for 

agreed upon actions, including milestone dates. We have no objections to the further release of 

this report to the public. This report will be available at http://www.epa.gov/oig. 
If you or your staff have any questions regarding this report, please contact Wade Najjum, 

Assistant Inspector General, at (202) 566-0832 or najjum.wade@epa.gov; or Carolyn Copper, 

Director for Program Evaluation, Hazardous Waste Issues, at (202) 566-0829 or 

copper.carolyn@epa.gov. 
 

 

 

 

 

 

EPA Should Improve Its Oversight of Long-Term 11-P-0034 

Monitoring at Wheeling Disposal Superfund Site in Missouri 

Table of Contents 

Chapters 

1 Introduction ........................................................................................................ 1 

Purpose ....................................................................................................... 1 

Background ................................................................................................. 1 

 Noteworthy Achievements .......................................................................... 2 

 Scope and Methodology.............................................................................. 2 

2 Incorrect Standards Used and Contaminants Improperly Analyzed ............ 4
 

Region 7 Inadvertently Allowed Use of Some Incorrect Standards............. 4 

Some Contaminants Improperly Analyzed .................................................. 5 

Five-Year Review Did Not Explain High Levels of Metals in 

Ground Water.................................................................................... 6 

Ecological Risk Assessment Needed.......................................................... 6 

Conclusion................................................................................................... 7 

 Recommendations ...................................................................................... 7 

EPA Region 7 Response to Draft Report and OIG Evaluation.................... 8 

Status of Recommendations and Potential Monetary Benefits.............................. 9
 

Appendices 

A Details on Sampling Methodology and Data Analyses................................... 10 

B Compounds With Incorrect Standards............................................................. 13 

C EPA Region 7 Response to Draft Report ........................................................ 15 

D Distribution ........................................................................................................ 17 
 

 

Chapter 1

Introduction 

Purpose 

The Office of Inspector General (OIG) of the U.S. Environmental Protection 

Agency (EPA) is evaluating long-term monitoring at Superfund sites deleted from 

the National Priorities List (NPL). This evaluation is to ensure that EPA has valid 

and reliable data on the conditions of these sites. Wheeling Disposal Superfund 

Site near Amazonia, Missouri, is one of eight sites reviewed. We collected ground 

water and surface water samples and compared our results to historical results 

reported by Region 7. We also compared results to applicable federal and state 

standards and conducted a site inspection. 

Background 

Wheeling Disposal Superfund Site operated from the 1970s through 1986. 

Wastes disposed at the site include leather tanning sludges, pesticides, asbestos, 

laboratory wastes, building debris, paint sludges, battery wastes, cyanide wastes, 

and miscellaneous crushed drums. The site’s 20-acre central disposal area sits in 

the middle of the 200-acre site. Surface runoff flows to tributaries and creeks 

north and south of the site and eventually discharges into the Missouri River 

2 miles south of the site. 

In 1989, EPA listed the site on the Superfund NPL. A consent decree between 

EPA and the responsible parties (RPs) established the remediation goals and 

cleanup objectives for the site. As defined in the site’s record of decision (ROD), 

the remediation objective was to eliminate current and prevent future 

unacceptable exposures to contaminated ground water, surface water, surface 

soils and sediments, and subsurface soils. According to the ROD, the performance 

criteria will be used to define whether the remedy will continue to be protective of 

human health and the environment over time. If the monitoring program indicates 

exceedance of the performance criteria, additional remedial activities may be 

required. The site remedy included upgrading the landfill cover and conducting 

long-term monitoring of ground water and surface water. Also, the remedy called 

for implementing site maintenance activities, installing security signs, and closing 

some onsite wells. In 1994, the RPs completed the remedial actions to eliminate 

unacceptable exposures. The site then transitioned to the operation and 

maintenance (O&M), or long-term monitoring phase. 

According to the consent decree, O&M activities will be conducted by the RPs. 

The purpose of O&M is to conduct such activities as site inspection, fence 

maintenance, cap or cover repair, and sampling. The RPs’ 1993 O&M plan 

provided the sampling and site maintenance activities and frequencies. 

11-P-0034 1 
 

 

Using data and information obtained from long-term monitoring activities at least 

once every 5 years, Region 7 must evaluate the site to determine if it is protective 

of human health and the environment. The results of this determination are reported 

in a publicly released Five-Year Review report. The region completed Five-Year 

Reviews for the site in 1999, 2004, and 2009. EPA’s Five-Year Review guidance 

establishes that exposure assumptions, toxicity data, cleanup levels, and remedial 

action objectives used at the time of the remedy selection should be evaluated to 

determine whether assumptions are still valid. The 1999 and 2004 reviews 

concluded that the remedy continued to protect human health and the environment. 

However, the 2009 review only found the remedy to be protective of human health 

and deferred making a statement on ecological protectiveness until an ecological 

risk assessment under current guidance was performed. 

Noteworthy Achievements 

Four landfill caps were constructed to cover the site’s industrial waste disposal 

areas. There were nine waste disposal areas including solid waste trenches, liquid 

waste trenches, evaporation ponds, a farm chemicals area, tannery waste disposal 

areas, and a rinsed container area. Region 7 imposed deed restrictions to prevent 

farming on certain onsite areas, and prohibited the use of ground water for the 

entire 200-acre site. A long-term monitoring program was developed to monitor 

the effectiveness of the remedy in preventing offsite migration of contaminated 

ground water and surface water. As part of its long-term monitoring program, 

Region 7 is conducting an ecological risk assessment to determine whether the 

remedy continues to be protective of the environment. 

Scope and Methodology 

We conducted this performance evaluation in accordance with generally accepted 

government auditing standards. Those standards require that we plan and perform 

the evaluation to obtain sufficient, appropriate evidence to provide a reasonable 

basis for our findings and conclusions based on our evaluation objectives. We 

believe that the evidence obtained provides a reasonable basis for our findings and 

conclusions based on our evaluation objectives. 

We conducted our work in two phases. In the first phase, from November 2007 to 

August 2008, we conducted a site visit, took ground water samples, and performed 

data validation on the sample results. In the second phase, from March 2009 to 

June 2010, we analyzed and compared OIG’s and Region 7’s sampling data. 

We reviewed relevant guidance documents and key decision documents, such as 

the 2001 Five-Year Review Guidance, consent decree, ROD, O&M plan, and 

Five-Year Reviews. We interviewed the site project managers and the program 

manager from both Region 7 and the Missouri Department of Natural Resources. 

Our ground water and surface water sampling methodology and data analyses are 

detailed in Appendix A. 

11-P-0034 2 
 

 

A draft of this report was sent to the Region 7 Administrator for official comment. 

Region 7’s comments on the draft report are in Appendix C. 

11-P-0034 3 
 

 

Chapter 2

Incorrect Standards Used and Contaminants 

Improperly Analyzed
 

Region 7 managers said they inadvertently allowed the RPs to use both incorrect 

and outdated surface water standards and outdated ground water standards when 

analyzing contaminant levels after the site remedy was completed. Region 7 also 

has not taken action to ensure RPs’ laboratories always use reporting limits that 

analyze sampling results down to the contaminant standard. By using the wrong 

standards and not analyzing results correctly, the region limits its ability to 

identify excess or unsafe levels of contaminants that could potentially migrate 

offsite. In the 2009 Five-Year Review, Region 7 did not explain whether site 

protectiveness was impacted by results that showed iron and aluminum exceeded 

standards at sampling locations used to detect potential offsite migration. Further, 

in response to OIG inquiries and Agency guidance, the region decided to conduct 

an environmental assessment to ensure the remedy is protective of the 

environment. The risk assessment will also enable the region to ensure current 

and appropriate standards are being used. Region 7 needs to improve its oversight 

of the RPs’ long-term monitoring activities to ensure protection of human health 

and the environment into the future. 

Region 7 Inadvertently Allowed Use of Some Incorrect Standards 

The RPs’ labs have been inadvertently using some incorrect surface water 

standards when analyzing sampling results at Wheeling. This occurred because 

Region 7 did not detect and correct the RPs using the wrong regulation in the 

annual monitoring reports they submitted to Region 7. The monitoring reports 

inform Region 7 of yearly contaminant levels at the site. Region 7’s oversight did 

not detect this error even though the consent decree and ROD cite the correct 

regulation, which is found in section 304(a) of the Clean Water Act. Instead, in 

analyzing the sampling results in the annual monitoring reports, the RPs 

inadvertently used some incorrect standards found in 40 Code of Federal 

Regulations (CFR) 131.36. The CFR is not the applicable regulation for citing 

surface water standards for Wheeling because the CFR does not apply to the State 

of Missouri, where the site is located. Region 7 needs to ensure that the RPs 

measure sample results against the correct standards. 

OIG’s review of the standards used to monitor surface water and ground water 

found that 29 standards for surface water contaminants and 12 for ground water 

contaminants were not updated when applicable standards were applied. 

Appendix B lists the 41 contaminants along with their correct standards. Twentyfive surface water standards and 7 ground water standards became more stringent 

through updates. Four surface water and five ground water standards became less 

stringent through updates. By inadvertently allowing incorrect standards, 

11-P-0034 4 
 

 

 

 

 

 

Region 7 may not have detected unacceptable levels of these contaminants in the 

site’s surface and ground water. In addition, where updated standards are now less 

stringent than those being used at the site, EPA could incorrectly identify 

unacceptable levels of contaminants. We found two contaminants 

(bromodichloromethane and tetrachloroethylene) exceeding the updated, but not 

the original, standards Region 7 is using. These exceedances were found at 

monitoring locations near the center of the site. Region 7 stated in the 2009 

Five-Year Review that it was not concerned with exceedances at wells positioned 

adjacent to the source area. As a result, site protectiveness decisions would not be 

altered due to these 2 exceedances. However, if exceedances of these two 

contaminants were to occur at other monitoring locations used to detect offsite 

migration of contaminants, Region 7 would not be able to detect these 

exceedances because it used outdated standards. 

Some Contaminants Improperly Analyzed 

Region 7 has not taken action in the past to ensure RPs’ labs always achieve a 

reporting limit that is at or below the contaminant standard. Reporting limits are 

the minimum concentrations of a compound or contaminant that can be measured 

by the lab with certainty. The O&M plan provides a list of contaminants that are 

monitored at the site and their respective reporting limits. These reporting limits 

generally have been set low enough to assess whether the lab is measuring down 

to each contaminant’s standard. However, Region 7 has not always ensured that 

the labs analyzed down to the standard. 

With the exception of the contaminants shown in Table 1, the RPs’ laboratories 

achieved the reporting limits at or below the standard for site contaminants. 

Table 1 shows the four contaminants we found that have reporting limits above 

the site’s ground water standards. The table also includes the six contaminants 

that have reporting limits above the site’s surface water standards. 

Table 1: 2007 reporting limits above the site’s standards1 

Ground water Surface water 

Contaminants 

monitored Standard 

2007 

reporting 

limit Analyte Standard 

2007 

reporting 

limit 

Atrazine (μg/L) 3 10 Arsenic (mg/L) 0.00014 0.005 

Antimony (mg/L) 0.006 0.05 Mercury (mg/L) 0.00015 0.0002 

Thallium (mg/L) 0.002 0.01 Silver (mg/L) 0.0035 0.005 

1,2-Dibromoethane 

(EDB) (μg/L) 0.05 1 Thallium (mg/L) 0.0063 0.01 

Selenium (mg/L) 0.005 0.01 

1,2-Dibromoethane 

(EDB) (μg/L) 0.05 1 

Source: Region 7’s annual monitoring reports. 

μg/L: micrograms per liter mg/L: milligrams per liter 

1 We used the stricter of the federal criteria for "Human Health Based on Consumption of Organisms Only" under 

Section 304(a) of the Clean Water Act (33 USC 1314(a)) or the Missouri water quality standards for protection of 

aquatic life under 10 CSR 20-7.031. 

11-P-0034 5 
 

 

 

When the labs’ report results for these contaminants fall between the standard and 

the reporting limit, Region 7 has limited assurance of the actual contaminant 

concentrations or whether exceedance of a standard has occurred. For example, 

the ground water standard for atrazine is 3 μg/L, while the reporting limit is 

10 μg/L. If atrazine were detected in a sample at 7 μg/L, it would exceed the 

standard. However, the lab’s use of the wrong reporting limits would cause it to 

fail to report this as an exceedance, because the lab cannot guarantee the certainty 

of the result below the reporting limit of μg/L. 

Five-Year Review Did Not Explain High Levels of Metals in 

Ground Water 

In the 2009 Five-Year Review, Region 7 did not explain or address standard 

exceedances for iron and aluminum at sampling locations close to the site 

boundaries. Likewise, the region’s 2004 review did not address exceedances for 

iron and aluminum. From 1999 through 2007, iron exceeded the standard in four 

out of nine sampling events, and aluminum exceeded the standard in four out of 

eight sampling events. The review should demonstrate that the remedy continues to 

protect human health and the environment and an explanation of the metals’ 

exceedances should have appeared in the review. Our analysis shows that iron was 

detected at levels within the background concentrations. This suggests that the 

levels of iron may be naturally occurring. However, the region’s 2004 Five-Year 

Review did not offer any explanation regarding the iron exceedances. In half of the 

samples taken to check for aluminum, the metal exceeded State of Missouri surface 

water standards at a sampling location that is intended to measure contaminants as 

they migrate offsite. In the 2009 Five-Year Review, Region 7 did not disclose these 

aluminum exceedances or address the likelihood of unsafe levels of aluminum 

migrating offsite. If aluminum is migrating offsite at levels above the standard, it 

may negatively impact the region’s current protectiveness determination. 

Ecological Risk Assessment Needed 

According to an EPA document, the entire 200-acre Wheeling site is a “habitat for 

wildlife and birds and is also a recreational hunting and fishing area.” During the 

site cleanup, the current site owner planted native wild grasses and other foliage 

that would attract birds and wildlife. During our onsite sampling event, we saw 

signs of wildlife and the site is used for hunting wildlife. Elevated concentrations 

of volatile organic compounds (VOCs) in onsite surface waters are shown in the 

historical sampling results and were also found in OIG’s independent sampling. 

However, the current site ROD does not address the protectiveness of onsite 

surface waters for ecological receptors, such as birds and wildlife. 

Given the elevated concentrations of VOCs in site surface waters and the 

designation of the site as a wildlife habitat, we asked Region 7 whether the site was 

still protective of the environment. The region responded that past risk assessments 

have found the remedy to be protective of the environment and the region believes 

11-P-0034 6 
 

 

 

 

this is still the case, because site conditions have not changed. However, the region 

believes that an environmental assessment under current Agency guidance is 

needed to verify that the remedy is protective of the environment. 

In its 2009 Five-Year Review, Region 7 stated that the environmental assessment 

concluded that a screening level ecological risk assessment should be conducted 

to ensure the remedy is protecting the environment.1

 The 2009 review further 

concluded that the site is primarily ecological in nature. Therefore, although the 

contamination may be contained onsite (thereby preventing human health 

exposure), the potential onsite impacts of the surface water on plants and animals 

may not have been fully addressed. In its response to the draft report, Region 7 

responded that it completed a Screening Level Ecological Risk Assessment for 

the Wheeling Disposal site on October 13, 2010. The region stated that the result 

of the assessment was that the remedy for the site is protective of the 

environment, and no changes to the remedy are necessary. Therefore, the region 

determined that a further ecological risk assessment is not necessary. 

Conclusion 

When the RPs reported their annual monitoring results, Region 7 inadvertently 

allowed the RPs to use some incorrect and outdated standards. The region 

acknowledged the use of outdated and incorrect standards to determine whether 

the remedy was protecting human health and the environment. Likewise, we 

found laboratories not analyzing results down to the reporting limits that were as 

low as the applicable standard, and the region used the lab results as part of its 

protectiveness determination. None of the problems we found had an adverse 

impact on the region’s protectiveness determination for human health. However, 

if incorrect standards continue to be used, or results are not properly analyzed, 

excess levels of contaminants could migrate offsite without Region 7’s 

knowledge. Region 7 must improve monitoring and oversight activities at 

Wheeling Disposal to assure that the site is protective for all current and future 

uses, including its primary “ecological use.” 

Recommendations 

We recommend that the Region 7 Administrator: 

1.	 Ensure updated and correct standards for surface water and ground water 

are used to assess conditions at the site and that these corrected standards 

are listed in all relevant site documents. 

2.	 Require that the reporting limits for all analyses are at or below the 

applicable standard to ensure that all contamination above the standard is 

properly analyzed by the laboratory. 

1

 Current Risk Assessment guidance for the environment is entitled Ecological Risk Assessment Guidance for 

Superfund: Process for Designing and Conducting Ecological Risk Assessments (EPA 540-R-97-006, 1997). 

11-P-0034 7 
 

 

 

3.	 Document in an addendum to the 2009 Five-Year Review that iron, 

aluminum, and any other compounds exceeding applicable standards are 

controlled at the site. 

4. Complete an ecological risk assessment to determine whether changes to 

the remedy are necessary and, if so, amend or generate new site 

documents, including the ROD, to ensure the site is protective of the 

environment. Issue an addendum to the 2009 Five-Year Review to include 

the results of the ecological risk assessment. 

EPA Region 7 Response to Draft Report and OIG Evaluation 

Region 7 agreed with all four OIG findings and recommendations. Where 

appropriate, we made changes to the report based on Region 7’s comments. 

For recommendation 1, Region 7 has made arrangements with the Wheeling 

Responsible Party group to perform a review of performance standards to ensure 

that the most current and appropriate standards are used in the annual monitoring 

program for the Wheeling Disposal site. This review is planned for early 2011 and 

will be completed by June 30, 2011. This recommendation is open with agreed-to 

actions pending. In its 90-day response to this report, the region should confirm 

the completion of this recommendation or update OIG on the status. 

For recommendation 2, Region 7 responded that it will require that the reporting 

limits for all analyses are at or below the applicable standards, and that this task 

will be performed as part of the performance standards review scheduled for early 

2011 and will be completed by June 30, 2011. This recommendation is open with 

agreed-to actions pending. In its 90-day response to this report, the region should 

confirm the completion of this recommendation or update OIG on the status. 

For recommendation 3, Region 7 agreed to issue by September 2011 an 

addendum to the 2009 Five-Year Review to document that iron, aluminum, and 

any other compounds exceeding applicable standards are controlled at the site. 

This recommendation is open with agreed-to actions pending. In its 90-day 

response to this report, the Region should confirm the completion of this 

recommendation or update OIG on the status. 

For recommendation 4, Region 7 stated that it completed the ecological risk 

assessment on October 13, 2010. The region stated that the risk assessment 

showed that the remedy for the site is protective of the environment, and no 

changes to the remedy are necessary. We revised recommendation 4 for Region 7 

to issue an addendum to the 2009 Five-Year Review to include the results of the 

risk assessment. Region 7 managers concurred with the revised recommendation. 

This recommendation is open with agreed-to actions pending. In its 90-day 

response to this report, the region should confirm the completion of this 

recommendation or update OIG on the status. 

11-P-0034 8 
 

 

 

 

 

 

Status of Recommendations and 

Potential Monetary Benefits 

POTENTIAL MONETARY 

RECOMMENDATIONS BENEFITS (in $000s) 

Rec. 

No. 

Page 

No. Subject Status1 Action Official 

Planned 

Completion 

Date 

Claimed 

Amount 

Agreed-To 

Amount 

1 7 Ensure updated and correct standards for surface 

water and ground water are used to assess 

conditions at the site and that these corrected 

standards are listed in all relevant site documents. 

O Region 7 Administrator 06/30/11 

2 

3 

4 

7 

8 

8 

Require that the reporting limits for all analyses are 

at or below the applicable standard to ensure that 

all contamination above the standard is properly 

analyzed by the laboratory. 

Document in an addendum to the 2009 Five-Year 

Review that iron, aluminum, and any other 

compounds exceeding applicable standards are 

controlled at the site. 

Complete an ecological risk assessment to 

determine whether changes to the remedy are 

necessary and, if so, amend or generate new site 

documents, including the ROD, to ensure the site is 

protective of the environment. Issue an addendum 

to the 2009 Five-Year Review to include the results 

of the ecological risk assessment. 

O 

O 

O 

Region 7 Administrator 

Region 7 Administrator 

Region 7 Administrator 

06/30/11 

09/30/11 

O = recommendation is open with agreed-to corrective actions pending 

C = recommendation is closed with all agreed-to actions completed 

U = recommendation is undecided with resolution efforts in progress 

11-P-0034 9 

1 
 

 

Appendix A 

Details on Sampling Methodology 

and Data Analyses 

Sampling Methodology 

We acquired a qualified environmental contractor to collect ground water and surface 

water samples and to conduct a limited site inspection in December 2007. The contractor 

collected samples from six onsite ground water monitoring wells and six surface water 

locations. OIG staff members were present to ensure that proper sampling and quality 

assurance protocols were followed. The samples were analyzed for VOCs, 

polychlorinated biphenyls (PCBs), metals (total and dissolved), organochlorine 

pesticides, 1,2-Dibromoethane (EDB), dinoseb, atrazine, and cyanide (total) at a qualified 

laboratory using EPA-approved methods. 

Data Analyses 

We analyzed our sampling data from the site to determine whether Region 7 has been 

obtaining valid and reliable data on the conditions at the site. We compared our results to 

historical data spanning back to 1999. OIG sampling results greater than 2 standard 

deviations above the average EPA historical concentrations were considered different. 

Our review did not include a full evaluation of the reasons for these differences. Where 

we observed differences, we compared OIG results to the relevant federal and state 

standards to determine whether OIG’s data had implications for human health or 

environmental protection. 

We also evaluated all OIG results to applicable standards and reviewed their potential 

effect on Region 7’s protectiveness determination for the site. The ROD established 

ground water and surface water cleanup standards for the purpose of determining whether 

the selected remedy will protect human health and the environment. The standards are 

developed and based upon relevant federal and state ground water and surface water 

regulations. Relevant federal and state standards are defined as (1) the Missouri Water 

Quality Standards [10 CSR 20-7.031], (2) the Federal Maximum Contaminant Levels for 

Inorganic and Organics in Drinking Water Supplies, and (3) the Federal Ambient Water 

Quality Standards as defined by the Clean Water Act. The ROD stipulates that, in the 

event that the monitoring program indicates exceedances of the standard, additional 

remedial activities may be required. Our approach and selection of applicable standards 

was consistent with the standards applied by EPA. 

The ROD also established a ground water and surface water monitoring system to 

determine the long term effectiveness of the remedy. The monitoring system was 

intended to provide an early warning before hazardous substances migrate offsite and 

harm human health and the environment. Ground water and surface water samples 

11-P-0034 10 
 

 

collected from various designated “compliance” locations would monitor the offsite 

migration of contaminants. Ground water and surface water cleanup levels must be 

achieved at these compliance points. 

Our results show OIG’s independent sampling and analyses generally confirm Region 7’s 

data at the Wheeling Disposal Superfund Site. Of the 116 compounds analyzed by the 

OIG and by EPA in the past, 5 were different from the region’s historical sampling 

results. The five analytes were manganese, potassium, sodium, total suspended solids, 

and total dissolved solids. These analytes either had no standards or their concentrations 

were detected below the standards. As a result, the OIG determined that these analytes do 

not have adverse implications for site protectiveness. 

OIG also identified 17 other contaminants that exceeded applicable standards (see 

table below). Region 7’s historical monitoring data also identified these exceedances. 

Thirteen of the 17 contaminants were detected at the center of the site near the 

contaminant source. Region 7 stated that elevated contaminant concentrations at the 

center of the site are expected and are not a concern because they do not indicate offsite 

migration. Two of the remaining four contaminants—total dissolved solids and 

manganese—are explained in the table footnote below. The other two contaminants— 

iron and aluminum—are discussed in the Five-Year Review section of the report. 

Compounds Exceeding Applicable Standards 

Analyzed 

compound 

Sampling 

location 

Compound 

class OIG result 

Original 

applicable 

standard 

1. 1,1-Dichloroethene 

( μg/L ) MW-35 I VOC 17 7 

2. 1,2-Dibromoethane 

(EDB) aka Ethylene 

Dibromide 

( μg/L ) 

MW-35 I VOC 14 0.05 

MW-35 I VOC 11.6 0.05 

3. 1,2-Dichloroethane 

( μg/L ) MW-35 I VOC 35 7 

4. Aluminum 

(mg/L) SW-35 Total Metal 1.5 0.75 

5. Carbon Tetrachloride 

(μg/L) MW-35 I VOC 2660 5 

6. Chloroform 

(μg/L) MW-35 I VOC 392 5.7 (80 THM total) 

7. cis-1,2­

Dichloroethene 

(μg/L) 

MW-35 I VOC 110 70 

8. Dichlorodifluorometh 

ane 

(μg/L) 

MW-35 I VOC 251 170 

9. Dinoseb 

(μg/L) MW-35 I VOC 36 7 

11-P-0034 11 
 

 

Analyzed 

compound 

Sampling 

location 

Compound 

class OIG result 

Original 

applicable 

standard 

10. 

Iron 

(mg/L) 

MW-35 D Total Metal 1.5 0.3 

MW-35 I Total Metal 0.511 0.3 

SW-35 Total Metal 1.7 1 

MW-32S Total Metal 0.422 0.3 

MW-32S Dissolved Metal 0.483 0.3 

MW-35 D Dissolved Metal 1.77 0.3 

MW-35 I Dissolved Metal 0.493 0.3 

11. 

*Manganese 

(mg/L) 

MW-35 D Total Metal 0.57 0.3 

MW-36I Total Metal 0.45 0.05 

MW-35 D Dissolved Metal 0.63 0.3 

MW-36I Dissolved Metal 0.47 0.3 

12. Methylene Chloride 

(μg/L) MW-35 I VOC 23.1 5 

13. Nickel 

(mg/L) 

MW-35 D Total Metal 0.753 0.1 mg/L 

MW-35 D Dissolved Metal 0.8 0.1 mg/L 

14. Thallium 

(mg/L) MW-35 I Dissolved Metal 0.0063 J 

15. 

*Total Dissolved 

Solids 

(mg/L) 

MW-32S _ 1580 0.5 mg/L 

MW-35 D _ 1320 0.5 mg/L 

MW-35 I _ 1540 0.5 mg/L 

MW-36I _ 410 0.5 mg/L 

16. Trichloroethene 

(μg/L) MW-35 I VOC 4320 5 μg/L 

17. Vinyl Chloride 

(μg/L) 

MW-35 D VOC 5.7 2 μg/L 

MW-35 I VOC 317 2 μg/L 

Source: OIG sampling. 

* Total dissolved solids do not show as an exceedance when the correct, updated standard is used. Manganese 

exceedances may be the result of background levels of the contaminant indicating that these may be naturally 

occurring and not originating from historical site activities. 

11-P-0034 12 
 

 

 

 

Appendix B 

Compounds With Incorrect Standards 

Surface water standard1 

Compound Original Updated 

1,1,2-Trichloroethane (μg/L) 42 16 3 

1,2-Dichlorobenzene (μg/L) NA 1,300 3 

1,2-Dichloroethane (μg/L) 99 37 3 

1,2-Dichloroethene** (μg/L) NA (cis) 

NA (trans) 

NA (cis) 

10,000 (trans) 3 

1,2-Dichloropropane (μg/L) NA 15 3 

Benzene (μg/L) NA 51 3 

Bromodichloromethane (μg/L) 22 17 3 

Carbon Tetrachloride** (μg/L) 4.4 1.6 3 

Chlorobenzene (μg/L) NA 1,600 3 

Ethylbenzene (μg/L) NA 320 4 

Methylene Chloride** (μg/L) 1,600 590 3 

Tetrachloroethene (μg/L) 8.85 3.3 3 

Toluene** (μg/L) 200,000 15,000 3 

Trichloroethene** (μg/L) 81 30 3 

Vinyl Chloride (μg/L) 525 2.4 3 

Endrin Aldehyde (μg/L) NA 0.3 3 

Heptachlor (μg/L) 0.00029 0.000079 3 

Antimony (mg/L) 4.3 0.64 3 

Cadmium (mg/L) 0.0091 0.0003 4,6 

Chromium (mg/L) 0.011 0.089 (III) 4,6 

0.01 (IV) 4 

Copper (mg/L) 0.019 0.011 4,6 

Lead (mg/L) 0.009 0.003 4,6 

Nickel (mg/L) 0.16 0.063 4,6 

Thallium (mg/L) 0.0063 0.00047 3 

Silver (mg/L) 0.0035 0.0047 4,6 

1,1-Dichloroethene** (μg/L) 3.2 7,100 3 

Ethylene Dibromide (EDB) 

(μg/L) 0.05 NA 

Mercury (mg/L) 0.00015 0.0005 4 

Zinc (mg/L) 0.103 0.142 4,6 

11-P-0034 13 
 

 

 

 

 

 

 

Compound 

Ground water standard2 

Original Updated 

1,2-Dibromoethane (EDB) (μg/L) NA 0.05 

1,2-Dichloropropane (μg/L) 5 0.52 4 

Bromodichloromethane (μg/L) 100 

80 

0.56 4 

80 (total THM) 

Chloroform** (μg/L) 100 5.7 4 

80 (total THM) 

Chloromethane (μg/L) 20 5 4 

Methylene Chloride** (μg/L) 5 4.7 4 

Tetrachloroethene (μg/L) 5 0.8 4 

1,1- Dichloroethane** (μg/L) 340 NA 

Acetone (μg/L) 260 NA 

Dichlorodifluoromethane (μg/L) 170 1,000 5 

Naphthalene (μg/L) 100 NA 

Total Dissolved Solids (mg/L) 500 NA 

 Source: Region 7’s annual monitoring reports. 

Standard became less stringent. 

Standard became more stringent. 

** Compound is an indicator chemical under the consent decree (per EPA data). 1

We used the stricter of the federal criteria for "Human Health Based on Consumption of Organisms Only"
 

under Section 304(a) of the Clean Water Act (33 USC 1314(a)) or the Missouri water quality standards for 

protection of aquatic life under 10 CSR 20-7.031. 

2

Stricter of the federal maximum contaminant levels under the Safe Drinking Water Act or the Missouri 

Water Quality Standards for drinking water [10 CSR 20-7.031]. 

3

Federal standard. 

4

State standard. 

5

EPA Lifetime Health Advisory, as required by Statement of Work. 6

Hardness assumption of <125. 

11-P-0034 14 
 

 

 

 

 

Appendix C 

EPA Region 7 Response to Draft Report 

MEMORANDUM 

SUBJECT:	 EPA Should Improve Its Oversight of Long-Term Monitoring 

at Wheeling Disposal Superfund Site in Missouri 

Report No. 2008-548 

FROM: Karl Brooks 

 Regional Administrator 

TO:	 Wade Najjum 

 Assistant Inspector General 

Office of Program Evaluation 

Thank you for the opportunity to comment on the draft report entitled, “EPA Should 

Improve Its Oversight of Long-Term Monitoring at Wheeling Disposal Superfund Site in 

Missouri.” 

Region VII offers the following clarification on the Background section of your report. 

The report states: 

The 1999, 2004, and 2009 reviews concluded that the remedy continued to 

protect human health and environment. However, the 2009 review also 

concluded that an ecological risk assessment was needed to ensure the remedy 

protects the environment. 

OIG is correct that the 1999 and 2004 reviews found the remedy to be protective of 

human health and the environment, but the 2009 review only found the remedy to be protective 

of human health. The 2009 review deferred making a statement on ecological protectiveness 

until an ecological risk assessment under current guidance was performed. 

11-P-0034 15 
 

 

Region VII generally agreed with your findings and offers the following comments on 

the recommendations: 

Recommendation 1 – Ensure updated and correct standards for surface water and 

groundwater are used to assess conditions at the site and that these corrected standards are 

listed in relevant site documents. 

Response: Region VII concurs with this recommendation. Region 7 has made arrangements 

with the Wheeling Potentially Responsible Party group to perform a review of performance 

standards to ensure that the most current and appropriate standards are used in the annual 

monitoring program for the Wheeling Disposal site. This review is planned for early 2011 and 

will be completed by June 30, 2011. 

Recommendation 2 – Require that the reporting limits for all analyses are at or below the 

applicable standards to ensure that all contamination above the standards is properly 

analyzed by the laboratory. 

Response: Region VII concurs with this recommendation. This task will be performed as part of 

the performance standards review scheduled for early 2011 and will be completed by June 30, 

2011. 

Recommendation 3 – Document in an addendum to the 2009 Five-Year Review that iron, 

aluminum, and any other compounds exceeding applicable standards are controlled at the 

site. 

Response: Region VII concurs with this recommendation. An addendum to the 2009 Five-Year 

Review will be completed by September 30, 2011. 

Recommendation 4 – Complete an ecological risk assessment to determine whether changes 

to the remedy are necessary; and, if so, amend or generate new site documents, including 

the Record of Decision, to ensure the site is protective of the environment. 

Response: Region VII concurs with this recommendation. Region 7 completed a Screening 

Level Ecological Risk Assessment (SLERA) for the Wheeling Disposal site on 

October 13, 2010. The result of the SLERA is that the remedy for the site is protective of the 

environment, and no changes to the remedy are necessary. Therefore, a further ecological risk 

assessment is not necessary. 

EPA looks forward to receiving your final report. Should you have any questions 

concerning this response, please contact DeAndre Singletary, Chief, Missouri/Kansas Remedial 

Branch at (913) 551-7373, or Kathy Finazzo, Regional Audit Follow-Up Coordinator, at (913) 

551-7833. 

11-P-0034 16 
 

 

Appendix D 

Distribution 

Office of the Administrator 

Assistant Administrator, Office of Solid Waste and Emergency Response 

Regional Administrator, Region 7 

Principal Deputy Assistant Administrator, Office of Solid Waste and Emergency Response 

Director, Office of Superfund Remediation and Technology Innovation, Office of Solid Waste 

and Emergency Response 

Agency Followup Official (the CFO) 

Agency Followup Coordinator 

General Counsel 

Associate Administrator for Congressional and Intergovernmental Relations 

Associate Administrator for External Affairs and Environmental Education 

Audit Followup Coordinator, Office of Solid Waste and Emergency Response 

Audit Followup Coordinator, Region 7 

11-P-0034 17