U.S. ENVIRONMENTAL PROTECTION AGENCY 

OFFICE OF INSPECTOR GENERAL 

Catalyst for Improving the Environment 

Hotline Report 

EPA Activities Provide Limited 

Assurance of the Extent of 

Contamination and Risk at a North 

Carolina Hazardous Waste Site 

 Report No. 10-P-0130 

May 17, 2010 
Report Contributors: Carolyn Copper 

 Angela Bennett 

 Kathryn Hess 

 Heather Drayton 

Abbreviations 

CIC Community Involvement Coordinator 

CIP Community Involvement Plan 

EPA U.S. Environmental Protection Agency 

NPL National Priorities List 

OIG Office of Inspector General 

OSC On-Scene Coordinator 

PRP Potentially responsible party 

SVE Soil vapor extraction 

TCE Trichloroethylene 

μg/L micrograms per liter 

VOC Volatile organic compound 

Cover photo: Former CTS Corp. facility at the Mills Gap Site, Asheville, North Carolina. 

(Photo courtesy EPA) 
 

U.S. Environmental Protection Agency 10-P-0130 

May 17, 2010 Office of Inspector General 

At a Glance 

Catalyst for Improving the Environment 

Why We Did This Review 

In response to a congressional

request, the U.S.

Environmental Protection 

Agency (EPA) Office of 

Inspector General (OIG)

opened a Hotline case to

examine the quality of recent 

EPA water and air sampling at 

the Mills Gap Site (Site)

located in Asheville, North 

Carolina. We also reviewed 

whether EPA clearly

communicated sampling 

results to residents. 

Background 

The Site has been in the State 

of North Carolina’s hazardous 

waste clean-up program since 

1993. EPA Region 4 has 

carried out emergency 

response actions at the Site 

since 1999. These actions 

included providing an 

alternative drinking water 

source for residents with 

unsafe levels of the chemical 

trichloroethylene, or TCE, in 

their drinking water. EPA’s 

current role is to ensure 

compliance with clean-up 

agreements and assess the 

extent of Site contamination. 

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/2010/ 

20100517-10-P-0130.pdf 

EPA Activities Provide Limited Assurance of 

the Extent of Contamination and Risk at a North 

Carolina Hazardous Waste Site 

What We Found 

The water and air quality sampling conducted at the Mills Gap Site has provided 

limited assurance of the extent of water and air contamination and risk at the Site. 

Within the records OIG reviewed, Region 4 adhered to accepted standards and 

practices in conducting its drinking water sampling in 2008 and 2009. However, 

the limited scope of Region 4’s past sampling activities and oversight kept the 

Region from detecting groundwater contamination in drinking water wells. 

Region 4 also adhered to accepted standards and practices in conducting its 2007­

2008 air sampling. However, an ineffective response action has not addressed the 

potential air quality risk that remains. 

Region 4’s letters to affected residents communicating water and air sample 

results contained jargon and technical language, did not clearly communicate 

safety issues, and could have been misleading to some. Although there have been 

some improvements in communications, Region 4’s drinking water letters did not 

disclose that water samples were only tested for site-related contaminants and the 

results do not indicate the overall safety of the water. 

Region 4’s Community Involvement Plan did not reflect all Site activities and did 

not include a communication strategy. Region 4 staff have not always 

documented conversations with residents or Site visits. These shortcomings 

impede Region 4’s ability to effectively manage community concerns and 

relationships. This complex site is of great interest to the community and poses 

public health risks. Region 4 must take into account these issues as it completes 

its response work and transitions the Site to the State. 

What We Recommend 

We recommend that Region 4 develop a plan for Site transition to the State, clarify 

resident communications, update the Community Involvement Plan, and improve 

recordkeeping. Region 4 generally agreed with five of our six recommendations. 

The remaining recommendation is under further review by the Region. The 

Acting Regional Administrator said the Region “will do everything within our 

authority to ensure the safety of the residents in the Mills Gap area.” 
 

 

 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

 Assistant Inspector General 

Office of Program Evaluation 

OFFICE OF 

INSPECTOR GENERAL 

May 17, 2010 

MEMORANDUM 

SUBJECT: EPA Activities Provide Limited Assurance of the Extent of 

Contamination and Risk at a North Carolina Hazardous Waste Site 

 Report No. 10-P-0130 

FROM: Wade T. Najjum

TO: A. Stanley Meiburg 

 Acting Region 4 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 findings that describe 

the problems the OIG has identified and corrective actions the OIG recommends. The OIG 

responded to EPA Region 4’s draft report comments by making changes to the report and 

providing responses to EPA Region 4, as appropriate. 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 – is $382,254. 

Action Required 

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

report within 90 calendar days. 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 me at (202) 566-0827 

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 Activities Provide Limited Assurance of the Extent of 10-P-0130 

Contamination and Risk at a North Carolina Hazardous Waste Site 

Table of Contents 

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

Region 4’s Oversight and Administration of Drinking Water Sampling 

Region 4’s Assessment of Air Quality Identified a Need for Monitoring 

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

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

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

Results of Review ................................................................................................................ 3
 

Was Limited ............................................................................................................... 3 

and Response Action at Contaminated Springs ....................................................... 4 

Region 4 Is Completing Removal Action, But Site Risks Remain.............................. 5 

Sample Results Were Not Clearly Communicated .................................................... 6 

Recordkeeping Practices Did Not Satisfy EPA Requirements................................... 8 

Community Involvement Plan Does Not Address Current Site Activities................... 9 

Conclusions ......................................................................................................................... 9
 

Recommendations............................................................................................................... 10 

EPA Region 4 Comments and OIG Evaluation ................................................................. 11 

Status of Recommendations and Potential Monetary Benefits....................................... 12 

Appendices 

A Detailed Scope and Methodology........................................................................ 13 

B EPA Region 4 Comments to Draft Report and OIG Evaluation ........................ 15 

C EPA Region 4 Response to OIG Follow-up Questions ..................................... 26 

D Distribution ........................................................................................................... 40
 
 

 

 10-P-0130 

Purpose 

We performed this evaluation in response to a request from a Member of Congress. We 

addressed the following questions: 

•	 Does Region 4’s assessment of drinking water and air quality at the Mills Gap Site assure 

the safety of drinking water and air quality? 

•	 Are results clearly communicated to affected residents? 

Background 

The Mills Gap Site (Site) centers on the former CTS Corp. electronics part manufacturing plant 

in Asheville, North Carolina. From 1959 to 1986, CTS conducted electroplating of metal parts. 

In 1987, Mills Gap Road Associates purchased the property from CTS and redeveloped 45 of the 

acres into residences. The remaining 9 acres include the manufacturing building within a 

perimeter fence (Figure 1). Figure 1: Entrance Gate to Former CTS Facility 

CTS used the chemical trichloroethylene 

(TCE) to clean metal parts at the facility. 

Drinking or breathing large amounts of 

TCE may cause impaired heart function, 

unconsciousness, and death. Skin contact 

with TCE for short periods may cause skin 

rashes. Studies of animals exposed to 

TCE have reported increases in lung, liver, 

kidney, and testicular tumors, and 

lymphoma. The U.S. Environmental 

Protection Agency (EPA) is currently 

reassessing the cancer classification of 

TCE. Source: EPA OIG photo taken July 2009. 

The North Carolina Department of Environment and Natural Resources (State) placed the Site on 

its list of Inactive Hazardous Sites in 1993. In 1999, the State asked EPA Region 4 to evaluate 

the Site for emergency removal action. The request followed the State’s sampling of 

contaminated springs on property next to the former CTS facility and a drinking water well about 

1⁄4 mile away. These samples revealed chemical contamination up to 4,200 times greater than the 

level for safe drinking water. In response to these results, Region 4 provided bottled water to the 

affected residents pending connection to the local municipal water supply. Based on additional 

sampling, Region 4 concluded that the soil beneath the former CTS building was potentially the 

source of chemical contamination in the drinking water springs and well. 

Under its Superfund removal authority, Region 4 has taken measures to evaluate threats posed to 

human health and minimize risks posed by the Site contaminants. These measures included 

installing systems to remove or destroy contaminants and investigating contaminants in the air in 

and around homes and near springs. 

1 
 

 

 10-P-0130 

Under State authority, the State named CTS as a responsible party at the Site in 2007. CTS then 

initiated a clean-up investigation under State oversight. The State released results of this 

investigation in July 2009. 

In December 2008, as part of its ongoing site assessment activities, Region 4 committed to 

quarterly sampling of drinking water wells in the area around the former CTS facility. This 

commitment was in response to concerns of residents regarding exposure to potentially 

contaminated groundwater. In 2009, Region 4, with assistance from local officials, conducted 

quarterly sampling of approximately 50 drinking water wells within 1 mile of the facility. 

Since 1985, Region 4 or the State has assessed contamination at the Site four times. In 2006, the 

Site was evaluated for EPA’s National Priority List (NPL). Currently, Region 4 is considering 

new information gathered since 2006 and reassessing the Site for NPL listing. If the Site again 

does not meet the criteria, Region 4 will transition its assessment activities to the State. The 

State will oversee future remedial activities through the State’s clean-up program. 

Noteworthy Achievements 

In 2004, Region 4 negotiated an Administrative Order on Consent (2004 agreement) with the 

potentially responsible parties (PRPs), CTS and Mills Gap Road Associates. The 2004 

agreement resulted in construction of a soil vapor extraction (SVE) system to reduce the quantity 

of volatile organic compounds (VOCs) leaching into the groundwater in a zone under and near 

the facility. We estimate that since operation began in 2006, the SVE system has removed over 

6,000 pounds of VOCs from the subsurface (equal to nine 55-gallon drums of TCE). Region 4 

oversees operation of the SVE system to ensure compliance with the 2004 agreement. 

During the April 2009 sampling of drinking water wells, Region 4 enforcement and 

investigations staff conducted a formal review of adherence to sampling procedures by the 

Region’s contractor, who had been tasked with conducting the sampling. The review resulted in 

on-the-scene correction of the problems found. These problems included purging wells too long 

and not checking the calibration of water quality meters at the end of each field day. 

Scope and Methodology 

We conducted this evaluation from June 2009 to February 2010 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 limited our review to compliance with those management controls related to the 

issues evaluated in the congressional request. 

To address our objectives, we interviewed past and present Region 4 site managers and staff 

involved with the Site. To obtain background information, we reviewed Region 4 documents 

and files. To evaluate the quality of Region 4’s sampling, we examined records from about 

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21 percent (34) of the 160 drinking water samples collected in wells from September 2008 to 

April 2009 and 100 percent (32) of the air samples collected in December 2007 and August 

2008. To determine the clarity of the Region’s communication of sampling results, we reviewed 

the letters reporting sampling results that the Region sent to the residents. We examined the 

letters associated with the 21 percent of the drinking water samples we reviewed and with 

100 percent of the air samples we reviewed. We also reviewed the Site Community Involvement 

Plan (CIP) and documents maintained by the Community Involvement Coordinator (CIC). In 

July 2009, we visited the Site to gain an understanding of the location, conditions, 

characteristics, and ongoing activities. 

Appendix A provides further details on our scope and methodology. 

Results of Review 

Region 4’s sampling of water and air quality at the Site provided limited assurance of the extent 

of water and air contamination at the Site. We concluded that the Region’s assessment of 

drinking water and air quality showed that the Region’s oversight and administration of drinking 

water sampling and assessment of air quality was limited. In addition, emergency response 

actions taken provided limited protection, and communication of sample results was not always 

clear. As a result, contaminated drinking water wells went undetected, Site risk remains, and the 

Region’s communications may have misled and confused some residents. 

We also found that the Region’s recordkeeping practices did not satisfy EPA requirements, and 

the Site CIP did not address current site activities. As a result, the Region may have impeded its 

ability to effectively respond to and manage community concerns and relationships. 

Region 4’s Oversight and Administration of Drinking Water Sampling Was Limited 

We reviewed Region 4’s drinking water sampling performed from September 2008 through 

April 2009. Our review of 21 percent of the sampling records showed that Region 4 adhered to 

accepted standards and practices in conducting its drinking water sampling. However, from 

1999 through 2009, Region 4 performed three separate emergency removal actions to eliminate 

threats to the public from contaminated drinking water. Removal actions recurred because 

Region 4’s oversight of the PRPs’ actions and its own actions were limited. As a result, 

contaminated groundwater went undetected. More oversight and sampling may have detected 

contaminated drinking water sooner. 

After its emergency response action in 1999, the Region executed the 2004 agreement with the 

PRPs. The 2004 agreement required the PRPs to develop a sampling plan for drinking water 

wells that were determined to have a reasonable potential for impact by releases from the Site. 

At the time, Region 4’s hydrogeologist, a member of the Region’s technical support staff, 

recommended evaluation of drinking water wells within 1 mile of the facility. The 

hydrogeologist recommended 1 mile because of the ability of contaminants to move a 

considerable distance in groundwater through fractured rock. 

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 10-P-0130 

In 2005, the contractor identified nine wells within approximately 1⁄2 mile of the facility with the 

potential for impact. Region 4 approved limiting sampling to these nine wells. In 2006, the 

PRPs’ contractor sampled five of the nine wells. According to the PRPs’ contractor, four wells 

were not sampled because two were not used for drinking water, one did not exist, and the owner 

of the fourth well declined to have the well sampled. We did not find evidence that Region 4 

attempted to contact, or request that the PRPs contact, the well owner who declined access. This 

lack of attempt to contact the owner is significant because the access letter sent to the well owner 

did not disclose that contamination from the former CTS facility might affect the well. 

Consequently, the well owner may have been unaware that water from the well was potentially 

contaminated. 

From late 2007 until April 2008, the State, with Region 4 support, expanded the sampling to 

include drinking water wells within approximately 1 mile of the facility. Of the wells sampled, 

one contained TCE at a concentration about 11 times the federal drinking water standard. 

Follow-up sampling by local officials also detected TCE in a nearby well. These wells were 

located in an area about 3⁄4 of a mile from the facility. In response, Region 4 initially provided 

bottled water to the residents and later installed filter systems for use until the homes could be 

connected to the local municipal water supply. 

In August 2009, Region 4 again discovered unsafe levels of contamination in a drinking water 

well that was within 1 mile of the facility – the well that the owner had reportedly declined 

access to in 2006. Neither the State nor Region 4 had included the well in their four subsequent 

sampling events. However, in August 2009, Region 4 sampled the well in conjunction with its 

site assessment activities. TCE contamination measured in the well water was about 160 times 

higher than the federal drinking water standard. Region 4 took emergency action and provided 

bottled water. Had Region 4 evaluated the completeness of its own well sampling, or conducted 

better oversight of the 2006 sampling done by the PRPs’ contractor, the Region may have known 

the extent of drinking water contamination earlier. 

Because of the August 2009 discovery, Region 4 completed a broader survey to identify drinking 

water wells missed in previous sampling events. This involved a door-to-door survey within 1 

mile of the facility. As a result, the size of the Region’s quarterly sampling doubled. Region 4 

will continue the quarterly well sampling while site assessment activities are conducted. 

However, if the Site does not qualify for the NPL, Region 4 will no longer have the authority to 

continue quarterly well sampling. In this case, the Region stated it will discuss with the State the 

transfer of this sampling activity to the State’s clean-up program. 

Region 4’s Assessment of Air Quality Identified a Need for Monitoring and 

Response Action at Contaminated Springs 

Region 4 adhered to accepted standards and practices for indoor and outdoor air sampling 

conducted in December 2007 and August 2008. The Region’s December 2007 air sampling 

results identified the need for additional sampling in the area around the springs on the east side 

of the former CTS facility. The results of the 2007 and 2008 sampling showed high TCE 

concentrations that exceeded the removal action level (action level) in the eastern springs and 

4 
 

 

 10-P-0130 

Figure 2: Warning Sign for Contaminated Springs 

Source: EPA OIG photo taken July 2009. 

showed the need for measures to address the TCE concentrations in the springs and in the air. 

Also, the Region identified a need to limit contact with the contaminated eastern springs. 

The Region conducted initial air sampling near the springs on both sides of the former CTS 

facility in December 2007. Region 4 conducted the sampling to determine whether TCE found 

in springs caused TCE vapors in air. Because of high TCE concentrations in the air near the 

eastern springs, a fence and warning signs were installed to isolate the springs and limit direct 

contact with the contaminated water and air (Figure 2). The results also identified a need for 

additional sampling. 

In 2008, Region 4 conducted additional 

air sampling at residences near the 

springs to further assess TCE vapors in 

the air. The results showed that while 

TCE concentrations in the immediate 

vicinity of the eastern springs exceeded 

action levels, data from all other 

locations were well below action levels. 

The Region concluded that TCE 

concentrations in the air decrease to 

below action levels at a fence line 

previously installed to limit exposure. 

Region 4 concluded that air conditions 

outside the fence were within an 

acceptable risk range. 

In addition to a fence and warning signs 

to limit exposures to TCE-contaminated springs, a pilot ozonation system was placed into 

operation in April 2009, to reduce levels of TCE in the springs. The system operated for 9 

months. The data obtained over this period showed that the system did not reduce TCE 

concentrations to the degree that warranted the system’s continued operation. Region 4 stated 

that the system was shutdown in January 2010. 

Region 4 Is Completing Removal Action, But Site Risks Remain 

According to Region 4, as it nears completion of its removal action, the Site will transition to the 

State for further action. Region 4 believes that remedial-type actions are necessary to address 

threats posed by the Site. Area residents will remain at risk from potential TCE exposure 

through coming into direct contact with contaminated springs and breathing nearby contaminated 

air. The Region plans to work with the State to implement a “seamless transition” from the 

Region’s removal program and site assessment activities to the States’ clean-up program. A 

seamless transition may help ensure that Site risks are appropriately communicated, documented, 

and addressed. 

5 
 10-P-0130 

TCE Contamination in Eastern Springs 

The PRPs operated a pilot ozonation system from April 2009 to January 2010 with the intent of 

reducing TCE concentrations in the eastern springs that formerly served as a drinking water 

source. However, during operation, three of the four springs showed concentrations that 

exceeded those measured in March 2009, 1 month before the system began operating. The PRPs 

also reported that the TCE level in a nearby groundwater monitoring well was significantly 

higher (53,000 micrograms per liter [μg/L]) than the highest level in the springs (36,000 μg/L) 1 

month before operation. Because the source of water for the springs is groundwater, TCE in the 

eastern springs may increase due to the higher TCE level in groundwater. 

TCE concentrations in nearby air could also increase if concentrations increase in the springs. 

However, the nature of this increase will depend on site-specific conditions. Results of air 

monitoring at and outside the fence around the eastern springs have not shown concentrations 

that exceed action levels. However, concentrations in the air have been measured only a few 

times and not at the same time as the water measurements. Simultaneous measurements in both 

surface water and air clarify the site-specific relationship between contaminant concentrations in 

the surface water and air. Increased concentrations in the springs above the concentrations 

discussed above may present the risk of exposure to contaminated air at and beyond the fence 

line. 

TCE Contamination in Western Springs 

A situation similar to the eastern springs occurs at the springs on the western side of the former 

CTS facility. A 2009 report prepared by the PRPs’ contractor shows that TCE concentrations in 

groundwater on the western side of the facility are also high (up to 35,000 μg/L). Because of the 

high concentrations in groundwater, the concentration of TCE in the western springs fed by that 

groundwater could increase. Consequently, concentrations in nearby air may also increase. 

Exposure risk may occur because the western springs are not fenced, or otherwise marked, to 

keep people away from the contaminated water and air. 

Sample Results Were Not Clearly Communicated 

Region 4’s letters to affected residents communicating water and air sample results contained 

jargon and technical language, did not clearly communicate safety issues, and could have been 

misleading to some. Although there have been improvements in the communications process, 

Region 4’s drinking water letters did not disclose that the water samples were only tested for 

site-related contaminants and the results do not indicate the overall safety of the water. The 

Region has not implemented an effective quality review process for its communications and did 

not follow EPA’s general guidelines for communications with the public. As a result, the Region 

may not have effectively managed community concerns and relationships. 

Region 4 Letters Did Not Communicate Limitations in Testing of Drinking Water 

The results in the letters we reviewed were accurate relative to the laboratory results. However, 

the letters did not disclose limitations in the laboratory testing that is needed to determine the 

6 
 10-P-0130 

overall safety of the water. The information provided to the residents may have led them to 

conclude that their water was safe, although Region 4’s limited testing did not provide enough 

information to make that determination. Since 2008, some aspects of Region 4’s letters to the 

residents regarding drinking water results have improved. 

The letters also did not disclose that Region 4 did not analyze for all chemicals recommended by 

EPA for safe drinking water. According to Region 4 staff, one of the objectives in monitoring 

the drinking water wells at the Site is to determine movement of contaminants from the Site. 

The Region did not conduct sampling that mirrors the routine testing required for public water 

systems or that EPA recommends for private well owners. The Region conducted the sampling 

to provide information to residents concerned about Site-related contaminants in their drinking 

water. 

The letters also did not disclose that some testing was not sensitive enough to determine whether 

a compound was present at the health screening level established by EPA (e.g., a drinking water 

standard or a risk-based screening level). In some cases, we found that laboratory reporting 

limits were higher than federal drinking water standards. This occurred because the samples 

were analyzed using hazardous waste program methods, not drinking water methods. As a 

result, the laboratory reporting limits for some metals, VOCs, and semi-VOCs were above the 

federal drinking water standards. Consequently, the safety of the drinking water relative to all 

drinking water standards cannot be assessed. 

Our review identified some improvements in recent letters, including: 

•	 A well-designed table that included relevant results from all samplings. 

•	 Health screening levels for compounds listed in the table of results. 

•	 A clear designation in the table of results when a compound was not detected. 

•	 Laboratory reports for the analyses conducted on the most recently collected samples. 

•	 Information on whom to contact for further information. 

•	 Notice of an upcoming session where Region 4, State, and local health department 

personnel would be available to answer well owners’ questions about the results. 

Region 4 Letters Did Not Clearly Communicate and Address Air Safety Concerns 

Letters to residents communicating the results of its outdoor and indoor air were accurate relative 

to laboratory results. However, some letters communicating air sample results were not clear 

and did not address safety concerns at the Site. The letters were not consistent with the 

principles of EPA’s public participation guidance. There was no quality review process in place 

to ensure that the letters were accurate, complete, clear, consistent, and readable for a general 

audience. As a result, EPA may be presenting sample results and associated risks in a way that is 

too technical, not understood by the residents, or could unnecessarily create or heighten resident 

safety concerns. 

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 10-P-0130 

EPA’s public participation guidance for On-Scene Coordinators (OSCs)1 states that OSCs must 

maintain consistent, timely, and accurate communications with the community. In addition, 

because discussions of removal actions can sometimes be highly technical, the OSC must present 

information in clear and easy-to-understand terms. The resident letters we reviewed varied in 

format, did not consistently report the same contaminants or the same standards, and did not 

clearly address safety concerns and potential risks. For example, letters state that sample results 

exceed reporting limits but are within EPA’s interim acceptable exposure limits and below 

Region 4’s Emergency Response action levels. However, the letters did not always include these 

limits or action levels or explain what these values mean and why they are or are not important. 

These statements do not convey the safety of the air in generally understandable terms. In 

addition, the letters did not include all contaminants tested or detected, and the language used 

was technical, making the letters difficult to understand. If the residents shared or compared 

letters, the differences and inconsistencies in the letters could result in additional concern and 

confusion on the part of the residents. 

The Region also did not conduct any independent quality review of the letters before sending 

them to the residents. We found one letter that referred to the wrong analytical report, one letter 

that included the wrong sample number, and one letter that was sent to the wrong address. Some 

letters referred to removal action levels while the referenced analytical report showed only 

reporting limits. Without adequate explanation of the limits and action levels, residents may not 

understand the purpose of, or the differences in, these standards of measurement. 

Recordkeeping Practices Did Not Satisfy EPA Requirements 

Region 4’s CIC did not document phone calls with residents or interactions with the community 

during Site visits. The CIC was not aware of specific program guidance or policy that requires 

such documentation. In addition, Site managers did not consistently maintain documentation to 

support their calls to residents regarding drinking water and air sample results. Region 4 staff 

should document these activities according to EPA’s records management policies and program 

requirements. 

Under the authority of the Federal Records Act, EPA’s Agency-wide Records Management 

Manual requires written documentation of meetings and site visits in certain circumstances. The 

Records Management Manual states that an information resource may be a record if it: 

(1) documents significant Agency decisions and commitments; 

(2) adds to proper understanding of the formulation or execution of Agency actions, 

operations, and responsibilities; 

(3) conveys information of value on important Agency activities; 

(4) facilitates action by Agency staff; 

(5) provides key substantive comments on a draft; and 

(6) makes possible a proper scrutiny by Congress or the Agency. 

1

 U.S. Environmental Protection Agency, Superfund Removal Procedures, Public Participation Guidance for OnScene Coordinators: Community Relations and the Administrative Record, July 1992. 

8 
 

 

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Based on our interviews with the CIC and the Site managers, we believe that Site visits and 

phone discussions with the community often met several of the six definitions described above. 

EPA’s Records Management Manual applies to all EPA programs and offices, and meeting its 

requirements would support improved Region 4 documentation of its Site-related discussions 

and interactions with the public. Documenting these types of public communications is also a 

good business practice. 

Community Involvement Plan Does Not Address Current Site Activities 

The CIP for the Site is limited to activities associated with Region 4’s removal actions. EPA’s 

guidance for Early and Meaningful Community Involvement provides that a CIP should be 

focused, current, and helpful. However, the existing CIP focuses only on the Region’s removal 

actions, even though the Region was sampling and conducting other site assessment work when 

it released the CIP in 2008. 

In addition, the CIP does not include a strategy for communicating current Site activities or 

conditions to the public. These missing components may impede the Region’s ability to 

effectively respond and manage community concerns and relationships. A CIP that addresses all 

Site activities, including coordination among those conducting work at the Site, and includes a 

communications strategy, should enhance community understanding regarding the Site. 

A communication strategy should be included in the CIP “when events or issues are complex or 

potentially sensitive,” according to the “Communication Strategies” file contained in EPA’s 

Superfund Community Involvement Toolkit. The communication strategy assists in avoiding 

“potential misunderstandings about difficult issues.” Moreover, it “develops vehicles to deliver 

information.” We identified several shortcomings in Region 4’s communications with the 

community that the Region could address with a communication strategy. Specifically, Region 4 

lacks: 

•	 A fact sheet and Website specific to remedial activities, and general public information 

on the range and progress of activities, overall sample results, and issues at the Site. 

•	 A complete and current mailing list for the community to facilitate notification regarding 

public meetings and other pertinent site information. 

•	 A site-specific hotline for reporting community concerns and providing community 

updates. 

•	 A system for announcing and holding periodic community meetings or availability 

sessions to discuss sampling results and ongoing and future site activities. 

Conclusions 

Over the last 10 years, Region 4 has taken multiple actions to address potential and actual public 

health threats from contaminated air and water at the Site. During this time, the Site has been 

under the jurisdiction of North Carolina’s Inactive Hazardous Sites Program and Region 4’s 

Emergency Removal Program. This complex site is of great interest to the community and poses 

public health risks. This Site does not have Superfund NPL status. We concluded that 

shortcomings in the Region’s oversight of activities under its authority have been a factor in not 

9 
 

 

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detecting some Site contamination until recently. In addition, the Region has not always 

communicated effectively with the community regarding the safety of drinking water and air 

around the Site. The Region’s Community Involvement Plan is incomplete; it neither addresses 

all of the Region’s activities at the Site, nor includes a communication strategy. The Region also 

had inconsistent recordkeeping practices. These shortcomings impede the Region’s ability to 

effectively respond to and manage community concerns. Region 4’s completion of its response 

work at the Site will neither remedy remaining Site contamination, nor mitigate potential future 

risks. The Region must be proactive in developing a clear plan to transition the Site to the State. 

Recommendations 

We recommend that the Region 4 Administrator: 

1.	 Complete and document the Region’s recent efforts to identify all drinking water wells 

within 1 mile of the former CTS facility. 

2.	 Modify future letters that communicate results of drinking water sampling to: 

a. Inform residents that the Region did not test drinking water wells for all 

compounds that EPA recommends for annual testing of private drinking water 

wells. 

b. Provide residents with directions on where they can obtain further information on 

testing the quality of their well water. 

c. Inform residents if testing cannot determine whether a compound was present in 

their well water at a drinking water standard or a risk-based screening level. 

3.	 Develop procedures and guidelines to ensure letters to the residents containing scientific 

and technical information are accurate, complete, clear, consistent, and readable for a 

general audience. The procedures should describe a quality review process designed to 

maintain compliance with developed guidelines. 

4. Develop a plan for the Site transition from Region 4 to the State. The plan should: 

a.	 Document the Region’s removal actions and site assessment activities previously 

undertaken. 

b.	 Identify outstanding issues and information about remaining Site risks. 

c.	 Be readable for a general audience, be made available to the public, and provide 

the public points of contact at the State. 

5. Provide community involvement and Superfund program staff with written guidance or 

policy that defines their responsibilities for complying with EPA’s records management 

policies when conversing with the public and conducting site visits. 

10 
 

 

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6.	 Develop a new Community Involvement Plan that addresses all ongoing Site activities 

and the community’s issues, needs, and concerns. The plan should identify specific 

activities, outreach products, or programs Region 4 will use to address the community’s 

concerns, and include a communication strategy for disseminating information to the 

public. 

EPA Region 4 Comments and OIG Evaluation 

The OIG made changes to this final report based on the Region’s draft report comments where 

appropriate. Specifically, we revised findings about the Region’s air quality assessment and 

replaced three draft report recommendations with one final report recommendation.2

 The full 

text of the Region’s comments and OIG evaluation are in Appendix B. The Region’s response to 

OIG follow-up questions is in Appendix C. 

Region 4 agreed with Recommendations 1, 2, 3, 5, and 6, but did not provide clear milestones for 

Recommendations 1, 2, and 5. Based on our follow-up, Region 4 provided estimated milestones 

of May 15, 2010, May 7, 2010, and April 30, 2010, for Recommendations 1, 2, and 5, 

respectively. Milestones provided for Recommendations 3 and 6 are October 1, 2010, and 

March 31, 2010, respectively. In response to Recommendation 6, Region 4 provided OIG with a 

CIP on April 27, 2010. OIG has not reviewed the CIP to determine whether it meets the intent of 

OIG’s recommendation. Although the milestones for Recommendations 1, 2, and 5 have passed, 

Region 4 has not informed OIG that the corrective actions for these recommendations are 

completed or provided updated milestones. All recommendations will remain open with agreedto actions pending. The Region’s 90-day response to this final report should provide OIG an 

update on the completion of activities for Recommendations 1, 2, 3, 5, and 6, as appropriate. 

Recommendation 4 replaces three recommendations in the draft report with which the Region 

did not agree. The OIG evaluation and information about the three removed recommendations 

are in Appendices B and C. 

In the Region’s general comments to the draft report, the Acting Regional Administrator said 

that Region 4 “will do everything within our authority to ensure the safety of the residents in the 

Mills Gap area.” Region 4 believes the removal action at the Site will reach established goals in 

the near future, and at that point, the removal action will be complete. Region 4 is nearing 

completion of its site assessment effort and is preparing to make a decision on NPL listing. 

Region 4 says it will work with the State to implement a seamless transition if the Site does not 

obtain NPL status. Region 4 expects the State will implement interim actions to address the TCE 

contamination in the springs and conduct additional monitoring of the springs and groundwater. 

Region 4 says it will coordinate with the State to ensure that the Region can respond 

appropriately should a change in conditions warrant additional removal action. 

2 OIG’s final report Recommendation 4 replaced Draft Report Recommendations 2, 3, and 4. 

11 
 

 

 

 

 

 

 

 

 

 

 

 

 

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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 

2 

3 

4 

5 

10 

10 

10 

10 

10 

Complete and document the Region’s recent 

efforts to identify all drinking water wells within 

1 mile of the former CTS facility. 

Modify future letters that communicate results of 

drinking water sampling to: 

a. Inform residents that the Region did not test 

drinking water wells for all compounds that EPA 

recommends for annual testing of private 

drinking water wells. 

b. Provide residents with directions on where they 

can obtain further information on testing the 

quality of their well water. 

c. Inform residents if testing cannot determine if a 

compound was present in their well water at a 

drinking water standard or a risk-based 

screening level. 

Develop procedures and guidelines to ensure 

letters to the residents containing scientific and 

technical information are complete, clear, 

consistent, and readable for a general audience. 

The procedures should describe a quality review 

process designed to maintain compliance with 

developed guidelines. 

Develop a plan for the Site transition from Region 4 

to the State. The plan should: 

a. Document the Region’s removal actions and site 

assessment activities previously undertaken. 

b. Identify outstanding issues and information 

about remaining Site risks. 

c. Be readable for a general audience, be made 

available to the public, and provide the public 

points of contact at the State. 

Provide community involvement and Superfund 

program staff with written guidance or policy that 

defines the responsibilities for complying with 

EPA’s records management policies when 

conversing with the public and conducting site 

visits. 

O 

O 

O 

U 

O 

Region 4 Administrator 

Region 4 Administrator 

Region 4 Administrator 

Region 4 Administrator 

Region 4 Administrator 

5/15/2010* 

5/7/2010* 

10/1/2010 

4/30/2010* 

6 11 Develop a new Community Involvement Plan that O Region 4 Administrator 3/31/2010**
 

addresses all ongoing Site activities and the 

community’s issues, needs, and concerns. The 

plan should identify specific activities, outreach 

products, or programs Region 4 will use to address 

the community’s concerns, and include a 

communication strategy for disseminating 

information to the public.
 

1 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 

*	 Although the milestones for Recommendations 1, 2, and 5 have passed, Region 4 has not informed OIG that the corrective actions for these 

recommendations are completed or provided updated milestones.

 **	 In response to Recommendation 6, Region 4 provided OIG with a CIP on April 27, 2010. OIG has not reviewed the CIP to determine whether it 

meets the intent of OIG’s recommendation. 

12 
 

 

 

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Appendix A 

Detailed Scope and Methodology 

We conducted our evaluation from June 2009 through January 2010 in accordance with 

generally accepted government auditing standards. We limited our review to compliance with 

those management controls related to the issues we evaluated in the congressional request. We 

reviewed Region 4’s drinking water sampling activities from September 2008 through April 

2009. We also reviewed Region 4’s air sampling activities in December 2007 and August 2008. 

To understand Region 4’s role and specific Site activities, we interviewed past and present Site 

managers (On-Scene Coordinators and Site Assessment Managers) and other involved regional 

staff. We also reviewed program documents and records applicable to the Site. 

To answer our two evaluation questions pertaining to the quality of Region 4’s assessment of 

drinking water and communication of results, we examined records from about 21 percent (or 

34) of the 160 samples collected from September 2008 to April 2009. We first randomly 

selected about 20 percent3

 of wells sampled in April 2009. Because the letters to residents 

reporting these sampling results also included results from the previous two samplings, these 

results were included as part of the 20 percent selected for each of the earlier sampling events. 

Letters communicating earlier results only included the results of that particular sampling. We 

selected additional records from the earlier sampling events to complete the 20 percent review. 

To assess the accuracy of the information sent to the residents, we compared drinking water 

results reported in the letters we reviewed to the laboratory reports. We also compared results to 

federal health screening levels to determine whether the Region properly identified possible 

problems with the groundwater. The health screening level for a particular tested compound was 

the federal drinking water standard, if a standard had been set. If no standard had been set, we 

used the risk-based screening level. We examined the laboratory reports to understand the 

accuracy of the laboratory methods relative to the health screening levels. We also examined 

field logbooks to determine whether the Region conducted the sampling using approved and 

standard procedures. 

To evaluate the drinking water letters that Region 4 sent to residents, we reviewed EPA guidance 

related to risk communication to the public. This guidance included, but was not limited to, (1) 

EPA’s Superfund Community Involvement Handbook (April 2005), and (2) EPA’s Risk 

Assessment Guidance for Superfund: Volume 1 – Human Health Evaluation Manual Supplement 

to Part A: Community Involvement in Superfund Risk Assessments (March 1999). We used this 

guidance to review selected letters to determine whether the letters: 

• summarized why the sampling was done; 

• were easy to read and free of technical and legal jargon; 

• were technically and legally accurate; 

3

 The selection goal was 20 percent for each of the three samplings. However, due to the discrete nature of the 

populations being sampled, the total for the results selected was about 21 percent. 

13 
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•	 were complete, providing all the needed information, including the applicable health 

standards; 

•	 summarized the results of the entire sampling effort and thus provided context for the 

individual results; 

•	 included directions for obtaining additional information; and 

•	 provided instructions on follow-up action, if needed. 

To answer our first evaluation question, pertaining to the quality of Region 4’s assessment of 

indoor and outdoor air quality, we reviewed key documents, including a work plan and a quality 

assurance project plan. We reviewed 82 air samples (including soil gas, subslab, indoor, and 

outdoor) collected by Region 4 in December 2007 and August 2008. Our primary focus was on 

the review of indoor and outdoor air samples. These samples represented 32 of the 82 reviewed. 

We reviewed soil gas and subslab samples to the extent needed to gain an understanding of how 

subsequent sample locations were determined. We compared sample results included in the 

letters to the residents to the analytical data reports to ensure accuracy of the data presented. We 

verified the screening limits or levels used in the letters to the residents with the applicable 

federal or State standard. We reviewed logbooks for the indoor and outdoor air sampling to 

determine whether the samples were collected as recommended in EPA’s November 2002 draft 

guidance titled OSWER Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air 

Pathway from Groundwater and Soils (Subsurface Vapor Intrusion Guidance). 

To answer our second evaluation question, pertaining to the accuracy and effectiveness of 

Region 4’s written communication of indoor and outdoor air sample results, we reviewed all 24 

individual letters to the residents. Similar to the review of drinking water letters, we identified 

and reviewed applicable EPA guidance related to risk communication to the public. Using this 

guidance, we reviewed the letters for accuracy, clarity, simplicity, consistency, and 

thoroughness, as we did with the drinking water letters. 

Issues related to recordkeeping, the Community Involvement Plan, and Site security arose during 

our review. To complete work associated with these issues, we identified Superfund community 

involvement guidance; compared community involvement documents or suggested practices 

with Region 4’s CIP and activities; and reviewed the CIC’s Site files. We also reviewed Site 

security requirements contained in the 2004 agreement and the August 2005 Removal Action 

Plan. We toured the Site, took photographs, and made observations on Site security. We 

obtained and reviewed EPA records, news articles, and publicly available crime reports for the 

area to determine trespasser, vandalism, or criminal activity at the Site. 

14 
 

 

 

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Appendix B 

EPA Region 4 Comments to Draft Report 

and OIG Evaluation 

March 5, 2010 

MEMORANDUM 

SUBJECT: Draft Office of Inspector General Report Titled EPA Activities Provide Limited 

Assurance of the Extent of Contamination at a North Carolina Hazardous Waste Site 

FROM: A. Stanley Meiburg 

Acting Regional Administrator 

TO: Wade Najjum 

Assistant Inspector General for Program Evaluation 

Thank you for the opportunity to provide comments to the Office of Inspector General of the 

U.S. Environmental Protection Agency (OIG) on the findings and recommendations contained in the 

draft report titled EPA Activities Provide Limited Assurance of the Extent of Contamination at a 

North Carolina Hazardous Waste Site. EPA’s mission to protect human health and the 

environment is our number one priority at the Mills Gap CTS Site and every other site at which 

we have oversight. We will do everything within our authority to ensure the safety of the 

residents in the Mills Gap area. 

Attached you will find our comments organized by OIG recommendation, with a statement of 

Region 4 agreement or disagreement and proposed timelines for implementation of corrective 

actions. 

If you have questions or need additional information, please contact me. Questions of a 

technical nature may be directed to Carolyn Callihan, callihan.carolyn@epa.gov, or (404) 562­

8913; Stephen Ball, ball.stephen@epa.gov, or (404) 562-8528; or James Webster, 

webster.james@epa.gov, or 404-562-8769. 

Again, thank you for the opportunity to comment on this report, and we appreciate the 

chance to work with you on behalf of the environment in Region 4. 

Attachment 

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 10-P-0130 

ATTACHMENT 

EPA Region 4 Responses to Office of Inspector General (OIG) Recommendations 

in Draft Report Titled EPA Activities Provide Limited Assurance of the 

Extent of Contamination at a North Carolina Hazardous Waste Site 

March 3, 2010 

EPA Region 4 believes that it is important to understand some of the broader context in which 

we are working at the Mills Gap Road Site (Site). The Superfund removal action began in 1999 

when Region 4 Emergency Response and Removal Branch (ERRB) connected certain families to 

the public water supply system because of tricholorethylene (TCE) contamination in their spring. 

Since that time, ERRB has aggressively utilized our removal authority to accomplish as much 

risk reduction as possible. Measures taken under our removal authority have included: (1) 

installation of a soil vapor extraction (SVE) system to remove volatile organic compounds 

(VOC) from unsaturated soil on the former CTS property; (2) installation of an ozonation system 

to destroy VOCs emanating from the springs on the Rice property; (3) investigation of the vapor 

intrusion pathway in homes closest to the former CTS property; and (4) investigation of ambient 

air impacts near the springs. All of these efforts, with the exception of the ozonation system 

which has been ineffective, have contributed to either better understanding threats posed to 

human health and/or minimizing those risks. 

As you know, Region 4 has used our site assessment process in an effort to determine whether 

this Site should be proposed to the National Priorities’ List (NPL) so that remedial authorities 

could be utilized to address ground water contamination at the Site. However, to date, Region 4 

has not documented a score of 28.5 or higher on the Hazard Ranking System for the Site’s 

inclusion on the NPL. Region 4’s evaluation efforts are continuing. 

Given the current situation, Region 4 believes the removal action will reach goals set forth in the 

removal action work plan in the near future and at that point the removal action will be 

completed. The North Carolina Department of Environment and Natural Resources (NCDENR) 

has the authority to address this Site under their Inactive Sites Program and, in fact, a 

comprehensive ground water and soil investigation is currently being conducted by the CTS 

Corporation pursuant to NCDENR’s authorities. Region 4 will work with the NCDENR to 

implement a seamless transition and expect they will implement interim actions to address the 

TCE contamination in the springs as well as bring the SVE system back online if site conditions 

warrant such an action. Additional monitoring of the springs and ground water will be 

conducted as part of this effort. We will coordinate with NCDENR through this effort so if 

conditions change that may warrant additional removal actions we can respond appropriately. In 

the meantime, Region 4 is nearing completion of the site evaluation effort and expects to be 

ready to make a decision on listing to the NPL by May of this year. 

The following comments are offered in response to OIG recommendations contained in the draft 

report titled EPA Activities Provide Limited Assurance of the Extent of Contamination at a North 

Carolina Hazardous Waste Site. 

16 
 

 

 

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Recommendation 1. Complete and document the Region’s recent efforts to identify all 

drinking water wells within 1 mile of the former CTS facility. 

Region 4 Response: We agree. The effort has been completed, with the exception of a 

few property parcels, where Region 4 is still attempting to obtain verification of the 

residential drinking water supply. The documentation of that effort is in progress. 

OIG Response 1: Based on additional information received from 

Region 4 on March 31, 2010 (Appendix C), OIG agrees with the 

planned corrective action and accepts the milestone of May 15, 2010. 

Although the milestone for Recommendation 1 has passed, Region 4 

has not informed OIG that the corrective action for the 

recommendation is complete or provided an updated milestone. The 

recommendation is therefore considered open with agreed- to actions 

pending. In its 90-day response to this final report, Region 4 should 

update OIG on the status of planned corrective actions in response to 

Recommendation 1. 

Recommendation 2. Conduct follow-up indoor air sampling at residences that were 

previously tested for chemical vapors originating from the surface water that is currently 

undergoing ozonation treatment. 

Region 4 Response: While additional data is almost always helpful, Region 4 disagrees 

with OIG Recommendation 2 for the following two reasons: 

•	 EPA conducted both initial and follow-up rounds of air sampling. The 

results confirm that indoor and ambient air concentrations in areas where 

exposure may occur are below EPA Region 4 Removal Action Levels (RALs) 

for TCE. 

The OIG report inaccurately states that no follow-up indoor air sampling has been 

conducted since the initial testing, and incorrectly suggests that EPA’s two 

separate air sampling events are one event. This is incorrect. The initial sampling 

event was carried out in December 2007. A follow-up study was conducted in 

August 2008. The follow-up sampling event was conducted in the summer to 

explore seasonal variations, as well as evaluate the results of the earlier sampling 

event. 

All sampling results were compared to the EPA Region 4 Removal Action Level 

(RAL) of TCE in air of 23 parts-per-billion by volume (ppbv). This RAL is based 

on protection for a residential indoor air exposure setting. EPA does not have an 

outdoor ambient air RAL; however the indoor air RAL was used to evaluate 

outdoor ambient air samples as a conservative approach. The highest airborne 

concentration identified during the initial and follow-up investigation was 3.78 

ppbv, which was measured in a crawlspace beneath a home. The crawlspace 

results from the follow-up event ranged from non-detect to 1.38 ppbv – more than 

17 
 

 

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an order of magnitude below the RAL of 23 ppbv. Per EPA’s November 2002 

OSWER Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air 

Pathway from Groundwater and Soils (Subsurface Vapor Intrusion Guidance), 

crawlspace air provides a direct measure of the potential for exposures from vapor 

intrusion. 

As none of the indoor or crawlspace results for either the initial or follow-up 

sampling events approached the RAL, Region 4 believes that indoor air has been 

adequately evaluated and no further sampling is necessary. 

•	 EPA’s Vapor Intrusion (VI) investigation, referred to in the OIG Report as 

indoor air sampling, was consistent with the national approach to VI 

investigations and was conducted in accordance with EPA guidance as 

appropriate relative to best professional judgment and years of practical 

experience conducting VI investigations. 

The VI investigation was conducted by the EPA Environmental Response Team 

(ERT) at the request of EPA Region 4. ERT is an EPA Special Team that 

provides technical and scientific planning and operational support to EPA 

Regions and is the national source for technical expertise in VI investigations. 

The investigation was planned and executed in accordance with the U.S. EPA’s 

November 2002 OSWER Draft Guidance for Evaluating the Vapor Intrusion to 

Indoor Air Pathway from Groundwater and Soils (Subsurface Vapor Intrusion 

Guidance) to the extent practicable given field conditions and using best 

professional judgment based on experience gained in conducting VI 

investigations since development of the draft guidance document. 

The OIG report faults EPA for not strictly adhering to the draft vapor intrusion 

guidance during the sampling events. Specifically, the draft guidance typically 

recommends that all appliances that may create a pressure gradient be turned off 

prior to and during sampling. 

Region 4 recognizes that this portion of the guidance was not strictly adhered to. 

However, from a practical standpoint, residents could not be expected to turn off 

their heat in winter and air conditioning in summer during sampling events. 

ERT suggests that leaving appliances such as heating and air conditioning 

systems running may create pressure gradients that can actually draw vapors into 

the structure, thus creating that worst case scenario referred to in the OIG report. 

This is a reason why VI sampling is recommended to be performed during the 

winter season. 

The OIG report fails to recognize that EPA facilitated temporary shutdown of the 

SVE system on the Site prior to and during the sampling event, specifically in 

order to temporarily maximize the potential for migration of organic vapors from 

the Site and increase the worst case scenario potential. 

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Finally, and as indicated previously, indoor TCE concentrations measured during 

the first sampling event (December 2007) ranged from non-detect to 3.78 ppbv, 

with the highest indoor concentration encountered during the investigation being 

obtained from within the crawlspace of a home. Though OIG has not accepted 

crawlspace results as indoor samples, they are generally considered a worst case 

scenario per the draft OSWER guidance. 

OIG Response 2: Based on Region 4’s response and additional 

information received from Region 4 on March 31, 2010 (Appendix C), 

we agree that follow-up indoor sampling at residences previously 

tested is unwarranted at this time. OIG removed this recommendation 

from the final report. However, while OIG believes additional testing is 

unwarranted at this time, any significant increases in TCE 

concentrations in the nearby springs may trigger the need for future 

indoor and outdoor air monitoring to ensure the safety of the residents. 

Region 4 should address this potential situation as part of the Region’s 

plan for transitioning the Site to the State upon completion of its 

removal action at the Site. This OIG concern is addressed in final 

report Recommendation 4. 

Recommendation 3. Conduct outdoor air monitoring on the eastern side of the former 

CTS facility near the contaminated surface water that is currently undergoing ozonation 

treatment. 

Region 4 Response: Again, while additional data is almost always helpful, Region 4 

disagrees with OIG Recommendation 3 for the following factors: 

•	 EPA conducted two sampling events (2007 and 2008) to evaluate outdoor 

ambient air impacts from nearby TCE contaminated springs. Though 

airborne TCE concentrations in the immediate vicinity of the springs east of the 

Site exceeded the RAL, these springs have been fenced to limit exposure 

potential, and data gathered in all other locations were well below RALs. The 

initial and follow-up investigations further demonstrate that ambient air intrusion 

is unlikely to result in indoor air concentrations above the RAL. 

•	 Data derived from the investigation represent the worst case. Ambient air 

samples were collected in biased locations (i.e., purposely placed in areas 

believed to have the potential for higher airborne TCE impacts). Contrary to the 

OIG report, samples were taken both east and west of the fence line in both indoor 

and outdoor samples. Specific sample locations were selected through 

consultation between the OSC and technical staff. 

•	 During the 2007 sampling event, the range of outdoor ambient air TCE 

concentrations were consistently below the RAL. Measured TCE 

concentrations in ambient air in locations other than immediately at the springs 

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themselves varied from 0.5 to 21 ppbv. The 21 ppbv value was obtained through 

an instantaneous sample that could never be duplicated in later sampling events. 

Follow-up sampling took place two days later at the location that yielded the 

higher (21 ppbv) detection and the result was 0.49 ppbv TCE. In 2008, two 24 

hour Summa Canister samples were collected at this location. Both Summa 

Canister samples yielded results of non-detect for TCE. Region 4 also notes that 

all the TCE concentrations, including the 21 ppbv result, were below EPA Region 

4’s RAL of 23 ppbv. 

•	 During the second sampling event in 2008, similar sampling locations were 

chosen and results ranged from non-detect to 0.975 ppbv of TCE. The results 

of the initial and follow-up rounds of sampling effectively demonstrate lack of air 

concentrations at levels of concern. 

•	 Airborne TCE concentrations immediately at the springs drop off rapidly to 

below RALs at the fence installed to limit exposure potential. Off gassing of 

TCE at the springs has been noted to be a source of TCE in ambient air at the Site. 

To assess the magnitude of off gassing and the potential risk to nearby residents, 

EPA conducted air sampling at the springs themselves. A sample collected 

immediately adjacent to the springs yielded a TCE concentration of 277 ppbv, 

above the RAL of 23 ppbv (based on a residential exposure). The removal action 

included installation of a fence and warning signs to isolate and limit direct 

contact to the springs. 

Air sampling around the springs demonstrated that TCE concentrations drop to 

below RALs at the fence perimeter. Two rounds of air monitoring around the 

perimeter of the fence have been conducted. The first sampling event took place 

during the 2008 sampling survey, and yielded an airborne TCE concentration of 

1.60 ppbv. The follow-up round of sampling was conducted by CTS, at the 

direction of EPA, and consisted of four (4) ambient air samples along the 

perimeter of the fence. The results ranged from 2.38 ppbv to 7.23 ppbv, all below 

Region 4’s RAL (based on a residential exposure). These multiple sampling 

results demonstrate ambient air conditions outside the fence are within acceptable 

risk range. 

•	 Given groundwater conditions, outdoor ambient air TCE data collected to 

date are believed to provide an accurate estimate of ambient air conditions 

over time. Samples collected at the contaminated springs east of the Site 

consistently yield TCE concentrations in the 20,000 micrograms-per-liter (ug/l) 

range. Samples collected from the stream formed by the springs (at the perimeter 

of the containment fence) are consistently in the 2000 ug/l range. These data 

indicate a consistent source of TCE volatilization to ambient air. However, 

ambient air in this area, which has been measured over 3 sampling events, show 

airborne TCE concentrations are well below the TCE removal action level of 23 

ppbv in all areas other than at the springs themselves. Given this uniformity in 

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source, Region 4 believes that TCE concentrations in ambient air will not change 

significantly over time. 

OIG Response 3: Based on Region 4’s response and additional 

information received from Region 4 on March 31, 2010 (Appendix C), 

we agree that outdoor sampling on the eastern side of the former CTS 

facility – outside the fenced springs area – is unwarranted at this time. 

OIG removed this recommendation from the final report. However, 

while OIG believes additional testing is unwarranted at this time, any 

significant increases in TCE concentrations in the nearby springs may 

trigger the need for future outdoor and indoor monitoring to ensure the 

safety of the residents. Region 4 should address this potential 

situation as part of the Region’s plan for transitioning the Site to the 

State upon completion of its removal action at the Site. This OIG 

concern is addressed in final report Recommendation 4. 

Recommendation 4. Conduct monitoring of surface water and nearby outdoor air on the 

western side of the former CTS facility to determine if there are unacceptable levels of 

contaminants in water and air. Assess for potential exposure and the need to mitigate. 

Region 4 Response: The OIG report states that because of high concentrations of TCE 

in groundwater, the concentrations of TCE in the western springs fed by the groundwater 

may increase with time. Consequently, the concentration of chemical vapors in air may 

also increase. Region 4 disagrees with the conclusion and with Recommendation 4 for 

the following reasons: 

•	 Springs west of the Site are not potable water sources and TCE 

concentrations are significantly lower than in the springs east of the Site. 

During the week of September 24, 2007, NCDENR Division of Waste 

Management sampled the stream along Mills Gap Road west of the site. The 

stream measured 247 ug/l of TCE and dissipated to 12.1 ug/l 220 feet further 

downstream. NCDENR again sampled the stream along Mills Gap Road west of 

the site in April of 2008 and results ranged from non-detect to 330 ug/l TCE. 

•	 TCE concentrations in ambient air west of the Site are consistently below the 

RAL. EPA sampled ambient air near the stream west of the site in August 2008. 

Results ranged from 0.184 ppbv to 0.975 ppbv. EPA also sampled ambient air at 

SSV, the residential area west of the Site. This event is not noted in the OIG 

report. The results, obtained through Summa Canister sampling, were non-detect 

for TCE. These results were all more than an order of magnitude below EPA 

Region 4’s RAL of of 23 ppbv for TCE and demonstrate that ambient air near the 

stream west of the site is within EPA’s risk range. 

•	 Given conditions and observations at the springs east of the Site, the western 

springs are an unlikely source of airborne TCE above the RAL. Surface 

water samples at the springs to the east of the site near the Rice property are 

21 
 

 

 

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historically high in concentrations of TCE. Samples in the springs and stream 

formed by the springs are consistently in the 20,000 and 2,000 ug/l range, 

respectively. However, ambient air in this area, which has been measured over 3 

sampling events, consistently shows air samples well below the TCE removal 

action level of 23 ppbv with exception of the eastern spring itself. Applying these 

findings to the stream to the west of the site, where surface water samples show a 

concentration of TCE at a maximum concentration of 408 ug/l (sampling event 

November 27-29 and December 11, 2007), we do not expect that concentrations 

in ambient air would become elevated over time beyond the removal action level 

of 23 ppbv. In addition, the exposure pathways of inhalation or ingestion from 

this stream are incomplete based on the fact that the stream is not a potable water 

source, and ambient air samples are below the TCE removal action level of 23 

ppbv. 

OIG Response 4: Based on Region 4’s response and additional 

information received from Region 4 on March 31, 2010 (Appendix C), 

we agree that monitoring of surface water and nearby outdoor air on 

the western side of the former CTS facility is unwarranted at this time. 

OIG removed this recommendation from the final report. However, 

while the OIG believes additional testing is unwarranted at this time, 

any significant increases in TCE concentrations in the groundwater 

and/or nearby springs may trigger the need for future surface water 

sampling and indoor and outdoor air monitoring to ensure the safety of 

the residents. Region 4 should address this potential situation as part 

of the Region’s plan for transitioning the Site to the State upon 

completion of its removal action at the Site. This OIG concern is 

addressed in final report Recommendation 4. 

Recommendation 5. Modify future letters that communicate results of drinking water 

sampling to: 

a. Inform residents that the Region did not test drinking water wells for all 

compounds that EPA recommends for annual testing of private drinking water 

wells. 

Region 4 Response: We agree. Region 4 will prepare and insert a disclaimer sheet with 

the results. We note that sample analyses cover over 90 additional metals and 

compounds that are not included as drinking water regulated constituents. 

Proposed timeline: Disclaimer to be sent out with next round of results letters in 

coordination with proposed workgroup timeline (see response to 2.d. below). 

b. Provide residents with directions on where they can obtain further information 

on testing the quality of their well water. 

22 
 

 

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Region 4 Response: We agree. Region 4 has now provided all residents on the 

monitoring network with EPA’s January 2002 Guidance entitled “Drinking Water from 

Household Wells,” EPA 816-K-02-003. This document was sent to all well owners for 

the 49 wells added to the monitoring network in September and early October. All other 

residents previously on the monitoring network received the document in January 2010, 

along with their October 2009 results. This document addresses the owners’ 

responsibility for their private wells, the need to have their wells tested periodically, and 

what organizations may be able to provide additional information or help with the testing, 

among other things. 

Further, for the last two quarterly events, Region 4 has offered to hold a public 

availability session to go over results with residents at their request. To date, no 

community member or resident has requested such a session. Region 4 has received 

positive feedback from residents regarding the new format of the results letters. 

c. Inform residents if testing cannot determine if a compound was present in their 

well water at a drinking water standard or a risk-based screening level. 

Region 4 Response: We agree. Region 4 has taken measures to lower the detection 

limits of most of the constituents on the VOC, semi-volatile organic compound (SVOC) 

and metals analyte list to the designated maximum contaminant level for the upcoming 

monitoring event scheduled for the week of February 22, 2010. If there is a compound 

present on the analyte list of which a lower detection limit cannot be reached, residents 

will be informed of such on the disclaimer sheet discussed previously. 

OIG Response 5: In the final report, this is Recommendation 2. 

Based on additional information received from Region 4 on March 31, 

2010 (Appendix C), OIG agrees with the planned corrective action and 

accepts the milestone of May 7, 2010. Although the milestone for 

Recommendation 2 has passed, Region 4 has not informed OIG that 

the corrective action for the recommendation is complete or provided 

an updated milestone. The recommendation is therefore considered 

open with agreed-to actions pending. In its 90-day response to this 

final report, Region 4 should update OIG on the status of planned 

corrective actions in response to Recommendation 2. 

Recommendation 6. Develop procedures and guidelines to ensure letters to the residents 

containing scientific and technical information are accurate, complete, clear, consistent, 

and readable for a general audience. The procedures should describe a quality review 

process designed to maintain compliance with developed guidelines. 

Region 4 Response: We agree. The Superfund Division will convene a workgroup to 

formulate policy and procedures (methods to be used, detection limits, disclaimers to be 

communicated, review process to be performed, language to be conveyed, etc.) for 

conducting private well sampling/monitoring and communicating results to well owners. 

The panel will consist of management, Remedial Project Managers (RPM), On-Scene 

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Coordinators (OSC), Community Involvement Coordinators (CIC), sample control staff 

and human health risk assessor staff. 

Timeline: October 1, 2010 

OIG Response 6: In the final report, this is Recommendation 3. 

Based on additional information received from Region 4 on March 31, 

2010 (Appendix C), OIG agrees with the planned corrective action and 

accepts the milestone of October 1, 2010. The recommendation is 

open with agreed-to actions pending. In its 90-day response to this 

final report, Region 4 should update OIG on the status of planned 

corrective actions in response to Recommendation 3. 

Recommendation 7. Provide Community Involvement and Superfund program staff with 

written guidance or policy that defines the responsibilities for complying with EPA’s 

records management policies when conducting conversations with the public and 

conducting site visits. 

Region 4 Response: We agree. The Agency’s Records Management Manual and the 

Superfund Community Involvement Handbook provide written guidance on the 

responsibilities for complying with EPA’s records management policies when conducting 

personal conversations with the public, either when on the phone or in person. 

Community Involvement and Superfund program staff is aware of these responsibilities. 

Regional managers will remind staff of these responsibilities at our upcoming All-Hands 

Meeting scheduled for March 11, 2010. 

In particular, Superfund managers will ensure that all staff is aware of the requirement to 

document site-related discussions and interactions with the public. The Site Team will, 

as required by the Agency’s Records Management Manual, keep a transcript of the public 

meetings conducted during the comment periods and make transcripts available to the 

public as part of the administrative record and information repository. Staff will also be 

made aware that other substantive discussions, such as telephone calls or meetings with 

individuals, must also be documented. 

CICs will be reminded that interviews are strictly confidential. Names, addresses, and 

phone numbers of private citizens should not appear in the Community Involvement Plan 

(CIP), and there should be no way to trace information or comments to any private 

citizens. However, local officials and representatives of Potentially Responsible Parties 

(PRP) interviewed in their official capacity should be indentified in the list of contacts. 

OIG Response 7: In the final report, this is Recommendation 5. 

Based on additional information received from Region 4 on March 31, 

2010 (Appendix C), OIG agrees with the planned corrective action and 

accepts the milestone of April 30, 2010. Although the milestone for 

Recommendation 5 has passed, Region 4 has not informed OIG that 

the corrective action for the recommendation is complete or provided 

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an updated milestone. The recommendation is therefore considered 

open with agreed-to actions pending. In its 90-day response to this 

final report, Region 4 should update OIG on the status of planned 

corrective actions in response to Recommendation 5. 

Recommendation 8. Develop a new Community Involvement Plan that addresses all 

ongoing Site activities and the community’s issues, needs, and concerns. The plan should 

identify specific activities, outreach products, or programs Region 4 will use to address the 

community’s concerns and include a communication strategy for disseminating 

information to the public. 

Region 4 Response: We agree. The CIC for the Mills Gap Site is currently in the 

process of developing a new CIP. The CIC is in the process of conducting the 

community interviews and will provide a general description of who has been 

interviewed. 

The new CIP will include a comprehensive community profile, including a site 

description, history, demographics, economy, community assets and unique needs. The 

CIP will describe what is known about environmental exposures, and identify key 

community needs, concerns, and expectations derived from community interviews. The 

CIP will provide citizens in this community with information and opportunities to 

participate as active partners in this assessment phase that affect the site in their 

community and to promote successful community participation throughout the process. 

The CIP will identify approaches to reach and engage the community, based on the 

uniqueness of the community. The CIP will discuss how Region 4 has been working and 

communicating with the citizens and will include a communication strategy that will 

design and enhance community involvement activities and how EPA plans to disseminate 

information to the public throughout the site investigation. The CIP will demonstrate that 

local citizens and EPA can work together effectively to protect human health and the 

environment. Finally, the Agency will make the CIP available to the public for comment 

before issuing a final CIP. 

Timeline for completion: March 31, 2010. 

OIG Response 8: In the final report, this is Recommendation 6. OIG 

agrees with the planned corrective action and accepts the milestone of 

March 31, 2010. In response to Recommendation 6, Region 4 provided 

OIG with a CIP on April 27, 2010. OIG has not reviewed the CIP to 

determine whether it meets the intent of OIG's recommendation. The 

recommendation is therefore considered open with actions pending. In 

its 90-day response to this final report, Region 4 should update OIG on 

the status of any additional planned corrective actions in response to 

Recommendation 6. 

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Appendix C 

EPA Region 4 Response to 

OIG Follow-up Questions 

March 31, 2010 

MEMORANDUM 

SUBJECT: Draft Office of Inspector General Report Titled EPA Activities Provide Limited 

Assurance of the Extent of Contamination at a North Carolina Hazardous Waste 

Site 

FROM: A. Stanley Meiburg 

Acting Regional Administrator 

TO: Wade Najjum 

Assistant Inspector General for Program Evaluation 

Thank you for the opportunity to provide comments to the Office of Inspector General of 

the U.S. Environmental Protection Agency (OIG) on the findings and recommendations 

contained in the draft report titled EPA Activities Provide Limited Assurance of the Extent of 

Contamination at a North Carolina Hazardous Waste Site. The purpose of this memorandum is 

to address follow up questions submitted to Region 4 by the OIG on March 11, 2010. Attached 

you will find our comments organized by OIG question and recommendation. 

If you have questions or need additional information, please contact me. Questions of a 

technical nature may be directed to James Webster at (404) 562-8769 or 

Webster.James@epa.gov, Carolyn Callihan at (404) 562-8913 or Callihan.Carolyn@epa.gov, or 

Stephen Ball at (404) 562-8528 or Ball.Stephen@epa.gov. 

Again, thank you for the opportunity to comment on this report, and we appreciate the 

chance to work with you on behalf of the environment in Region 4. 

Attachments 

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ATTACHMENT 1 

EPA Region 4 Responses to Office of Inspector General (OIG) Follow up 

Questions Submitted on March 11, 2010, Relative to the Draft Report Titled 

EPA Activities Provide Limited Assurance of the Extent of Contamination 

at a North Carolina Hazardous Waste Site 

OIG Question 1 - Ozonation System: Region 4's response to the OIG draft report states that 

the ozonation system "installed to destroy VOCs emanating from the springs on the Rice 

property" was ineffective. In our meeting on February 25, 2010, Region 4 staff stated that the 

ozonation system had been dismantled. 

a.	 On the basis of what information did Region 4 determine that the system was ineffective? 

Please provide the OIG with that information along with the Supplemental Removal Action 

Plan, August 2008, which does not appear to be in SDMS or on the Mills Gap OSC website. 

b.	 When was the ozonation system dismantled/taken 'off-line'? 

c.	 How and when will Region 4 communicate with the affected and interested public that the 

system has been dismantled? 

Region 4 Response: 

a.	 The August 20, 2008 Supplement to Removal Action Plan of February 4, 2005 is attached 

(Attachment 2). Performance of the pilot ozonation system was evaluated based on 

comparison of surface water quality data generated prior to and during the pilot study. The 

intended purpose of the ozonation system was to treat trichloroethylene (TCE) contaminated 

groundwater discharging at multiple springs located immediately east of the Mills Gap 

Groundwater Contamination Site (Site), located in Skyland, Buncombe County, North 

Carolina. 

CTS, under order by EPA Region 4, collected 10 months of surface water sample data as part 

of the ozone pilot study. A baseline sample event took place on March 19, 2009. After the 

system came online in April 2009, nine additional monthly sample events took place to 

measure changes in TCE concentration in surface water resulting from ozone injection. 

During the months of operation of the pilot ozonation system, no change in TCE 

concentrations were observed relative to the baseline sampling event. It was thus concluded 

that the ozonation system was not having a measurable effect on TCE concentration at the 

springs. 

The surface water data was collected at the four springs on the east of the Site and one stream 

sample at the fence boundary downstream from the springs. Spring 1 was only sampled 

seven months due to consistently low concentrations. Table 1 below contains a summary of 

data collected and shown in the Draft Report of Removal Action Pilot Study (Attachment 3). 

Also shown is the mean and median of the collected data showing average conditions for 

Springs #3 and #4 of approximately 20,000 micrograms-per-liter (ug/l). 

27 
 

 

 

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Table 1 

Concentration of TCE 

Sample Location Range (ug/l) Mean (ug/l) Median (ug/l) 

Spring 1 1.3 – 290 85.69 5.9 

Spring 2 12,000 – 21,000 15,600 15,000 

Spring 3 11,000 – 25,000 20,000 20,500 

Spring 4 2,900 – 36,000 20,790 21,500 

Surface Water 1 1,800 – 3,000 2,330 2,300 

Additional information on performance of the pilot ozonation system, including data tables 

and a sample location figure, can be viewed in the Draft Report of Removal Action Pilot 

Study (Attachment 3). 

b.	 The pilot ozonation system was shutdown on January 14, 2010, and dismantled (removed 

from fenced springs area) on January 15, 2010. The injection points and small 'wellheads' are 

still at the Site, and may be removed upon final approval of the pilot study report. 

c.	 Region 4 communicated termination of the ozone system to select community representatives 

at the Mills Gap Congressional meeting on Friday, January 22, 2010. The community 

members in attendance were Barry Durand, Aaron Penland, Tate MacQueen, and Dave 

Ogren. At the meeting Mr. Durand indicated that he represented the Rice family. Once the 

Draft Report of Removal Action Pilot Study becomes final, a fact sheet will be distributed to 

the community to inform them of the event and outcome. 

OIG Question 2 - SVE System: Region 4's response to the OIG draft report states that 

NCDENR may "bring the SVE system back online if site conditions warrant such action." This 

statement implies that operation of the SVE system has been discontinued. However, that is not 

stated in the Region's response. 

a.	 Was the SVE system stopped and when? 

b.	 On the basis of what information did Region 4 determine that the system was no longer 

needed? Please provide the OIG with that information. 

c.	 How and when will Region 4 communicate with the affected and interested public that the 

system has been/will be shut down? 

Region 4 Response: 

a.	 The statement in the initial Region 4 response to the draft OIG report was poorly worded and 

therefore misleading. No, the SVE system has not been shutdown. It is still in operation at 

this time. 

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b.	 As indicated, the SVE system is still in operation at the Site. However, evaluation of the 

effectiveness of the system and any eventual decision on its operation will be based on 

analysis of its performance at removing volatile organic compounds (VOCs) from the 

subsurface. 

Removal action goals are discussed under Section 4.0 of the Revised Removal Action Plan 

(Attachment 4). Specifically, “to evaluate the constituent recovery rates and determine when 

they have reached an asymptote, at which time further operation of the SVE system will be 

unnecessary, a regression analysis will be performed on the data.”4

 Air samples are collected 

from the SVE system once per month to estimate the mass of VOCs removed from the 

subsurface, unsaturated zone. At such time that a statistical analysis of the mass recovery 

rate demonstrates a slope that is indicative of an asymptote, the effectiveness of the SVE 

system may be considered exhausted and termination of its operation will be considered. 

c.	 Once the SVE system has attained the goals stated in the Revised Removal Action Plan, 

Region 4 will coordinate an availability session or a public meeting as appropriate to convey 

the results to the community. 

OIG Question 3 - Removal Action Goals: Region 4's response to the OIG draft report states 

"given the current situation, Region 4 believes the removal action will reach goals set forth in the 

removal action work plan in the near future and at that point the removal action will be 

completed." 

a.	 What are the removal action goals? 

b.	 On the basis of what information will the Region determine that the goals have been met? 

c.	 How and when will Region 4 communicate with the affected and interested public that the 

removal action goals have been met? 

d.	 Is a public comment period required? 

Region 4 Response: 

a.	 The approved Revised Removal Action Plan specifies in Section 4.0, “the removal action 

standard that is proposed for this project, and the method for determining when the standard is met, is 

based on reaching asymptotic recovery rates from the SVE recovery wells1

. To perform this 

evaluation, certain vapor samples will be collected and analyzed for USEPA Method 8260 VOCs. 

Concentration data will be plotted versus time to illustrate the changes in removal rates with the 

ongoing operation of the removal system. Typically, the removal of constituents from environmental 

media occurs in a logarithmic scale.” 

4

 A statistical analysis to fit a curve through the set of measurements (recovery rates over time). An asymptote in 

the case of the SVE system may be assumed when the rate of VOC removal from the subsurface is approaching zero 

along a trend into infinity (i.e., may get infinitely close but never actually reach zero). 

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b.	 Evaluation of the effectiveness of the system and any eventual decision to discontinue its 

operation will be based on analysis of its performance at removing VOCs from the 

subsurface. See Region 4 response to OIG question 2.b., above, for additional details of 

evaluation of the SVE system. 

c.	 Once the SVE system has attained the goals stated in the Revised Removal Action Plan, 

Region 4 will coordinate an availability session or a public meeting as appropriate to convey 

the results to the community. 

d.	 No, a public comment period is not required relative to the determination that the goals of the 

removal action have been attained. 

OIG Question 4 - Seamless Transition to NCDENR: Page 1 of your response states "...expect 

they will implement interim actions to address TCE contamination in the springs..." 

a.	 What is the basis for assuming interim actions, vs. long-term actions are needed? 

b.	 Has the Region had discussions with the NCDENR regarding what interim actions will be 

taken? 

c.	 What are the interim actions the Region envisions? 

d.	 What assurances does Region 4 have from NCDENR that they will implement interim 

actions to address the TCE contamination in the springs? 

e.	 What authority, if any, permits the Region to enforce or require NCDENR interim actions? 

f.	 If all interim actions are led by NCDENR, what is Region 4's oversight role at the site, in 

addition to completing its site assessment activities? 

Region 4 Response: 

a.	 Region 4 believes remedial-type actions are necessary to address the threats posed by the 

site. Interim actions may be warranted during the site characterization process to collect and 

treat contaminated water emanating from springs which EPA has discussed with NCDENR. 

To address long-term actions, historically EPA has utilized several different technologies at 

similar contaminated ground water sites including, extraction and treatment, in-situ 

treatment, and monitoring of natural processes. Each of these alternatives requires 

considerable characterization and design which can take years to accomplish, followed by 

years of remedial action. 

b.	 Yes, the Region has discussed the potential interim actions with NCDENR. 

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c.	 The Region has discussed two possible interim actions with NCDENR: (1) collection and 

treatment of contaminated water emanating from the springs; and (2) continuing to operate 

the SVE system. 

d.	 Region 4 has no assurances from NCDENR at this point, but we will continue to 

communicate with our counterparts at NCDENR. 

e.	 EPA has no authority to enforce or require actions by NCDENR under their Inactive Sites 

Program, however we work closely with NCDENR in every facet of the Superfund program 

and we will offer technical support at this site, and any site, should they request it. 

f.	 EPA does not have a formal oversight role on sites in NCDENR’s Inactive Sites Program. 

As stated above in (e), EPA can provide technical support on sites in the NCDENR Inactive 

Sites Program when requested. 

OIG Question 5 - Recommendation 1: Complete and document the Region’s recent efforts 

to identify all drinking water wells within 1 mile of the former CTS facility. 

a.	 When do you expect that verification will be completed? 

b.	 How is the effort being documented? 

c.	 When do you expect documentation to be completed? 

d.	 Please provide an overall estimated milestone completion date for both of these efforts. 

Region 4 Response: 

a.	 Verification should be completed by April 15, 2010. 

b.	 EPA has constructed a GIS-based parcel map of the 1-mile radius around the Site, which is 

based upon the Buncombe County Land Records parcel map. Each parcel is color-coded 

showing if the property is supplied by municipal water, a private well, or not supplied. The 

methodology behind this analysis was a process of documenting previously known 

information, elimination of parcels without structures and parcels served by municipal water, 

followed up with a ground survey (door-to-door survey). The GPS points from historical 

sampling events were identified and overlaid onto the GIS Buncombe County Land Records 

parcel map layer. Multiple GPS points for each parcel and from different sampling events 

identified known parcels on well water. This information was then cross-referenced against 

a database to identify which residents have wells currently being sampled. The City of 

Asheville provided data referencing of current property parcels currently supplied by city 

water. These parcels were removed from the parcels on well water within a 1-mile radius. 

Apparent vacant parcels were systematically removed by referencing each parcel against the 

Buncombe County Property Record Card to confirm if any structures were on the property. 

Lots were also viewed by Google Maps aerial images and Image Connect to verify if 

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structures were on the parcels. We are currently in the process of verifying the status of a 

remaining handful of parcels. Documentation will consist of the actual GIS-based map, the 

Scribe Database, notes from the door-to-door survey, access agreements and well 

information forms, telephone call logs, and notes. An Excel spreadsheet will accompany this 

information and will contain information on each parcel documented that contains a private 

well. Information will include, owner name, address, number of population on the well, 

contact name and number, and miscellaneous notes. Documentation should be completed 

within one month of completion of verification. 

c.	 This action will be completed by May 15, 2010. 

d.	 Both actions will be completed by May 15, 2010. 

OIG Question 6 - Recommendation 2: Conduct follow-up indoor air sampling at 

residences that were previously tested for chemical vapors originating from the surface 

water that is currently undergoing ozonation treatment. 

We understand Region 4's position that the sampling in December 2007 was the initial sampling 

and that the Region considers the sampling conducted in August 2008 to be the follow-up 

sampling. However, our discussion in the report pertains to the lack of follow-up sampling after 

startup of the ozonation system to determine its impact on indoor and outdoor air quality. As 

discussed in the report, the Region believed that the ozonation system would reduce TCE vapors 

in the residences. To our knowledge, no additional (or follow-up) sampling was conducted 

outside the fence line surrounding the system and stream to determine the impact of the 

ozonation system. We do not agree that the August 2008 sampling was "follow-up" sampling 

for purposes of testing the effectiveness of the ozonation system. 

a.	 Why does Region 4 think it unnecessary to conduct a second round of indoor breathing space 

sampling when EPA's Draft 2002 Vapor Intrusion Guidance states "Two or more sampling 

events at each location are desirable" (p. E-5). To our knowledge, the Dec 2007 sampling 

included "crawlspaces" and not "breathing zones"? 

b.	 Region 4 has concluded that TCE vapors within the house closest to the contaminated 

springs east of the former CTS facility is from ambient air and that the springs are the 

primary source for the TCE vapors in ambient air. Why did Region 4 not conduct an 

additional round of indoor breathing space sampling, even though the sampling conducted in 

August 2008 showed low ambient air concentrations relative to the higher concentrations in 

December 2007? 

Region 4 Response: 

Region 4 did not understand that the follow-up sampling referred to by the OIG was specific to 

the ozonation system. Thank you for that clarification. Region 4 acknowledges that no followup VI or ambient air sampling was conducted once the ozone system was brought online for the 

purposes of evaluating impacts the Ozone system may have had on ambient air. This was due to 

the finding that the ozonation system had no impact on TCE concentrations at the springs or in 

32 
 

 

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surface water, and therefore there would be no expected change in concentrations of TCE in 

ambient air. See Region 4 response to OIG Question 1.a., above for a description of the 

evaluation of the ozonation system. 

a.	 Region 4 believes that a crawlspace air sample represents a worst case scenario of a 

breathing zone. First, because at this Site, ambient air is the believed source of indoor TCE, 

and the crawlspace in this case was believed to be representative of ambient air in close 

communication with the home. Also note that air sampling at the springs has shown that 

ambient air TCE concentrations are uniformly lower than the RAL for indoor air at the fence 

line surrounding the springs (i.e., no air sample taken outside the spring fenced area has ever 

exceeded the residential RAL). Secondly, crawlspace samples as a worst case estimate of 

indoor TCE concentrations is supported by the U.S. EPA’s November 2002 OSWER Draft 

Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and 

Soils (Subsurface Vapor Intrusion Guidance), which states that crawlspace air provides a 

direct measure of the potential for exposures from vapor intrusion. Therefore one round of 

indoor air sampling and two rounds of crawlspace samples, none of which exceed the indoor 

air RAL of 23 parts-per-billion by volume (ppbv), are a sufficient measure of the potential 

exposure threat posed by ambient air migration into a home. The first round of sampling 

(Dec. 2007) included a crawlspace air sample from the house closest to the spring. The 

crawlspace was selected as the sample location based on discussions with the EPA 

Environmental Response Team (ERT) that the crawlspace would show the highest air 

concentration of TCE in the home. The sample result was 3.78 ppbv. This sample was 

significantly below the EPA Emergency Response and Removal Branch (ERRB) Removal 

Action Level (RAL) of 23 ppbv. However, since TCE was detected in air, and as a 

conservative measure, the home was resampled during the August 2008 sampling event 

(Attachment 5). During this event it was decided that both the crawlspace and the interior of 

the home would be sampled. The crawlspace sample was 1.38 ppbv and the indoor air 

sample result was 1.27 ppbv. The indoor air sample was lower than the crawlspace sample, 

which indicates that the crawlspace sample is representative of the worst case scenario. In 

addition, the August 2008 follow-up sampling event provided two more data points 

significantly below the RAL. Two sampling events consisting of two crawlspace samples 

and one interior sample, all of which are significantly lower than the RAL provided the 

ERRB with a reasonable basis for determination that additional sampling was unwarranted. 

b.	 As indicated under (a), all sample results from the subject house were well below the RAL, 

and as Region 4 believes, in this case, crawlspace air sample represents a worst case scenario 

estimate of a breathing zone. As crawlspace samples during both sample events were below 

the RAL, further follow-up sampling was not warranted. 

OIG Question 7 - Recommendation 3: Conduct outdoor air monitoring on the eastern side 

of the former CTS facility near the contaminated surface water that is currently 

undergoing ozonation treatment. 

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OIG wrote draft recommendation 3 regarding air monitoring assuming that sampling of surface 

water (springs and stream) would continue. 

a.	 Now that the AOC respondents have dismantled the pilot ozonation system, what continued 

monitoring is Region 4 requiring them to carry out? 

b.	 Region 4 states that "airborne TCE concentrations immediately at the springs drop off 

rapidly to below RALs at the fence." Could Region 4 please provide us a map that shows the 

location of the fence relative to the spring, stream, outdoor air, crawl space and indoor air 

sampling locations? 

c.	 Region 4 states that the "data derived from the investigation represent the worst case." Why 

have concentrations in the springs not been measured at the same time as ambient air? 

Without these simultaneous measurements, how is Region 4 able to claim that it understands 

the contribution of TCE from the springs to ambient air and that the ambient air 

measurements represent the worst case? 

d.	 Table 7 of the 2009 Phase I Remedial Investigation Report presents the water quality data for 

the springs and streams. According to this table, spring locations 1 and 2 on the eastern side 

have been sampled six times since 1999 with measured concentrations ranging from 1,900 

ug/l to 34,000 ug/l. Does Region 4 have additional data that supports its claim that "samples 

collected at the contaminated springs east of the Site consistently yield TCE concentrations 

in the 20,000 micrograms-per-liter (ug/l) range"? Please provide all the monitoring and 

location data that the Region used to make the various claims in its response to Draft 

Recommendation 3. 

Region 4 Response: 

a.	 The Region 4 Emergency Response and Removal Branch (ERR) is not requiring the PRPs to 

monitor the springs or downgradient stream under the current AOC. Region 4 believes that 

10 months of water quality data in the east springs are a sufficient measure of concentrations 

that will continue to be observed in the springs and stream. See Region 4 response to OIG 

question 1.a., above for information regarding monitoring of the springs and stream during 

evaluation of the ozonation system. 

b.	 A map showing the location of the springs and the outdoor ambient air samples collected by 

MacTec (a consultant to the PRPs) is attached (Attachment 6). Additional maps showing the 

various air sampling events and types of samples collected by EPA are also attached 

(Attachments 5 and 7). New maps are being generated to combine all sampling events onto 

one map. Those maps will also show the location of the fence around the springs. Those 

maps are expected to be completed by March 29, 2010, and can be made available to the 

OIG at that point; however this is a compilation of existing data and no new information will 

be presented on these maps. 

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c.	 The springs have been sampled consistently over a 10 month period during the ozone pilot 

study. Sample results from the springs are consistent (See Table 1 under Response 1.a., 

above). Region 4 believes this amount of time gives an accurate representation of spring 

conditions over time and that further spring sampling concurrently with indoor air or 

crawlspace sampling is not necessary to draw the conclusion that air samples represent a 

worst case scenario. In addition, during the start-up of the ozone system an outdoor ambient 

air sampling event was conducted in conjunction with the baseline spring (surface water) 

sampling event in March of 2009. The data below shows perimeter fence line air monitoring 

as well as surface water concentrations at each of the four springs during the same month 

(Table 2). Note that at Spring 4, the TCE concentration in ambient air at the exclusion fence 

was well below the RAL (for indoor residential air) even at a TCE concentration in surface 

water at the spring of 36,000 ug/l. 

Table 2 

Concentrations of TCE 

Air at Fence Line 

(March 31, 2009) 

AA-01 AA-02 AA-03 AA-04 

2.93 ppbv 2.38 ppbv 7.23 ppbv 6.38 ppbv 

Surface Water 

(March 19, 2009) 

Spring 1 Spring 2 Spring 3 Spring 4 

1.3 ug/l 14,000 ug/l 11,000 ug/l 36,000 ug/l 

Additionally, in December of 2007, NCDENR did conduct a surface water sampling event 

that coincides with EPA’s initial crawlspace air sampling event. See the Table 3 below for 

data comparisons. 

Table 3 

Concentrations of TCE 

EPA 

Crawlspace Air 

December 2007 

MGSC01 

(Southside 

Village, west 

springs) 

 MGSC25 (Rice 

home, east 

springs) 

 0.161 ppbv 3.78 ppbv 

NCDENR 

Surface Water 

December 2007 

CTS-013-SW 

(west springs) 

CTS-012-SW 

(west stream) 

CTS-008-SW 

(east spring) 

CTS-009-SW 

(east spring) 

408 ug/l 39.4 ug/l 18,000 ug/l 11,600 ug/l 

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These data further demonstrate that the worst case scenario can be determined as well as 

shows that concentrations of TCE in indoor and outdoor air emanating from the springs has 

not been and is not expected to be above EPA’s RAL for indoor air of 23 ppbv. Please see 

Attachments 7 and 8 for more information on data distribution and correlation. 

d.	 Please refer to Region 4 response to OIG question 1.a. for a explanation of our basis for 

20,000 ug/l as the estimation of average conditions in the eastern springs. Please refer to 

Region 4 response to (c), above, for a discussion of TCE concentrations in ambient air 

relative to TCE concentrations in springs. 

OIG Question 8 - Recommendation 4: Conduct monitoring of surface water and nearby 

outdoor air on the western side of the former CTS facility to determine if there are 

unacceptable levels of contaminants in water and air. Assess for potential exposure and the 

need to mitigate. 

Region 4's position is that the conditions are unchanging (in steady state) and that the limited 

sampling that has been conducted sufficiently establishes that levels of TCE in the western 

springs are not high enough to warrant concern. We do not accept these claims that conditions 

are steady and concentrations will not become high. As we have stated in our draft report, 

concentrations of TCE in groundwater on the western side are high, as shown in the 2009 Phase I 

Remedial Investigations Report. We expect that concentrations in the groundwater-fed springs 

on the western side will increase. No sampling of these springs has been conducted in 23 

months. What information does Region 4 have to support its claim that conditions are 

unchanging? 

Region 4 Response: 

As indicated in our March 5, 2010, response, surface water west of the Site was sampled by 

NCDENR in September 2007, November/December 2007, and April 2008. On the first 

occasion, the highest TCE concentration found was 247 ug/l, which dissipated to12.1 ug/l within 

approximately 200 feet downstream of the source (Attachment 9). During the second event, the 

highest TCE concentration observed was 408 ug/l (Attachment 8). During the third event, TCE 

concentrations ranged from non-detect to 330 ug/l TCE (Attachment 10). Ambient air sampling 

conducted near the stream on the west side of the Site conducted in August 2008 yielded 

airborne TCE concentrations of 0.184 ppbv to 0.975 ppbv. Ambient air sampling conducted in 

the residential area west of the Site yielded results of non-detect for TCE. 

Given that the stream west of the Site is not a current source of potable water and that all air 

sampling results are well below the RAL of 23 ppbv, Region 4 believes that these areas have 

been adequately assessed with respect to the emergency response and removal program. Region 

4 also notes that the Phase I report referenced by OIG above was produced by CTS under the 

direction and oversight of NCDENR, and, should NCDENR request, ERRB will review and act 

upon, as appropriate, any future data generated through any State oversight investigation of the 

Site. 

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Region 4 further based its initial response to OIG Recommendation #4 through comparison with 

conditions observed east of the Site where even though measured surface water concentrations 

are approximately two orders of magnitude higher than in the west, ambient air concentrations 

are well below RALs in all areas other than at the spring head itself (See Table 1 under Response 

1.a., above). 

OIG Question 9 - Recommendation 5: Modify future letters that communicate results of 

drinking water sampling to: 

a.	 Inform residents that the Region did not test drinking water wells for all compounds 

that EPA recommends for annual testing of private drinking water wells. 

Could Region 4 please clarify the proposed timeline for the actions proposed to address 

Recommendation 5a? For this timeline, the Region refers OIG to "see response to 2.d. below". 

However, there is no response 2d. 

b.	 Provide residents with directions on where they can obtain further information on 

testing the quality of their well water. 

The OIG accepts the proposed action and acknowledges that Region 4 has already completed 

the proposed action. That completion will be noted in the final report. 

c.	 Inform residents if testing cannot determine if a compound was present in their well 

water at a drinking water standard or a risk-based screening level. 

What is Region 4's proposed milestone date for sending out the letters to residents 

communicating the results of the sampling that was conducted in February 2010? 

Region 4 Response: 

a.	 We mistakenly referenced 2.d. The correct reference is 2.c. We expect to mail out the 

February well monitoring results by May 7, 2010. The Superfund Division work group (see 

Recommendation 6) to formulate policy and procedures for communicating multi-media 

results to residents should complete their work by October 1, 2010. Obviously, these two 

deadlines do not coincide. However, the work group will prioritize the work on formulating 

the disclaimer for the private well water samples, so that the disclaimer can be sent out with 

the February results, if possible. 

b.	 Region 4 thanks the OIG for acceptance of the proposed action. 

c.	 The time from sampling date until final letters are sent out to the residents takes on the 

average 8-10 weeks. We would expect that residents would be sent their results by May 7, 

2010. 

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OIG Question 10 - Recommendation 6: Develop procedures and guidelines to ensure 

letters to the residents containing scientific and technical information are accurate, 

complete, clear, consistent, and readable for a general audience. The procedures should 

describe a quality review process designed to maintain compliance with developed 

guidelines. 

In order to address this recommendation, the Region needs to include communication of other 

sampling, such as sampling ambient, indoor, subslab, and crawl space air, conducted on private 

residential property. We communicated this during our February 25, 2010, meeting. At that 

time, the Region agreed that the scope of their corrective action plan to address this 

recommendation would extend beyond drinking water letters. Region 4 seemed to understand 

that recommendation 6 applied to letters communicating results of all sampling conducted at 

private residences. OIG's final report will include direction to the Region about what specific 

actions OIG needs to see in the Region's 90-day response to the final OIG report. That response 

includes details on corrective action plans to address OIG recommendations and that haven't 

been provided prior to that time. 

Region 4 Response: 

Region 4 agrees that procedures and guidelines for clear communication of scientific and 

technical information should address all environment media and investigations. The workgroup 

referenced in our March 5, 2010, response to OIG Recommendation 6 will address multienvironmental media scientific and technical information. 

OIG Question 11 - Recommendation 7: Provide Community Involvement and Superfund 

program staff with written guidance or policy that defines the responsibilities for 

complying with EPA’s records management policies when conducting conversations with 

the public and conducting site visits. 

In order to address this recommendation, the Region needs to develop a corrective action plan 

that provides Regional staff with written guidance or policy that defines responsibilities for 

complying with EPA's record management policies. The Region's draft response says it will 

provide "verbal communication" of the responsibilities. The Region can complete this 

recommendation by issuing a management memo/all-hands memo to all Regional staff outlining 

their responsibilities. 

Region 4 Response: 

Region 4 agrees with the OIG’s recommendation. We will develop and distribute an all-hands 

memo to the Regional staff outlining roles and responsibilities for complying with EPA’s record 

management policies. The timeline for completion of this action is within 30 days of the date of 

this memorandum. 

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OIG Question 12 - Recommendation 8: Develop a new Community Involvement Plan that 

addresses all ongoing Site activities and the community’s issues, needs, and concerns. The 

plan should identify specific activities, outreach products, or programs Region 4 will use to 

address the community’s concerns and include a communication strategy for disseminating 

information to the public. 

The OIG finds the response and timeline for completion acceptable. 

Region 4 Response: 

Region 4 thanks OIG for acceptance of the proposed action. 

Summary of Region 4 Actions or Deliverables 

A summary of the actions and/or deliverables identified within the preceding Region 4 responses 

to OIG follow up questions is given in Table 4, below. 

Table 4 

Summary of Region 4 Actions and/or Deliverables Identified Within Attachment 1 

Region 4 

Response 

Action or Deliverable Completion Date or Comment 

1.a. Fact Sheet on Report of Removal Action Pilot 

Study 

Upon finalization of Draft Report of 

Removal Action Pilot Study 

2.c. Availability session or public meeting to 

discuss SVE system goals and status 

Upon SVE system having attained 

goals as stated in Revised Removal 

Action Plan 

5.a. Verification of drinking water wells within 1 

mile of former CTS facility 

April 15, 2010 

5.c. Documentation of drinking water wells within 

1 mile of former CTS facility 

May 15, 2010 

5.d. Milestone completion date for verification 

and documentation 

April 15, 2010 for verification and 

May 15, 2010 for documentation 

7.a. New maps with compilation of past sampling 

events 

March 29, 2010 

9.a. Mail out of analytical results of February 

2010 monitoring results of residents 

May 7, 2010 

9.a. Formulation of proposed policy and 

procedures for communicating multi-media 

monitoring results to residents 

October 1, 2010 

11 All hands memorandum outlining roles and 

responsibilities for compliance with EPA 

record management policies 

Within 30 days of date of this 

memorandum 

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Appendix D 

Distribution 

Office of the Administrator 

Acting Regional Administrator, Region 4 

Agency Follow-up Official (the CFO) 

Agency Follow-up Coordinator 

General Counsel 

Associate Administrator for Congressional and Intergovernmental Relations 

Associate Administrator for Public Affairs 

Audit Follow-up Coordinator, Region 4 

Acting Inspector General 

40