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United States Environmental Protection Agency

5 Post Office Square, Suite 100 

Boston, MA 02109-3912 

MEMORANDUM

DATE: June 17, 2014

SUBJ: Responsiveness Summary

FROM: Terrence Connelly 

 TO: Deletion Docket 

Introduction 

 

 A Notice of Intent to Delete for the O’Connor Superfund Site (Site) was published in the 

Federal Register on March 12, 2014 (Vol. 79, No. 48, pages 13967-13968). The publication of 

this notice was intended to inform the public that EPA planned to delete the Site from the 

National Priorities List (NPL), and provide a 30-day public comment period on the proposed 

deletion. The closing date for comments on the Notice of Intent to Delete was April 11, 2014. 

Two written comments were received; therefore, EPA has prepared this Responsiveness 

Summary. In addition, all public comments were considered in EPA’s final decision to delete 

the Site from the NPL. 

Responsiveness Summary 

 The Responsiveness Summary has been prepared to provide responses to comments 

submitted to EPA during the 30-day public comment period regarding the Notice of Intent to 

Delete (Vol. 79, No.48, pages 13967-13968) of the O’Connor Superfund Site. The original 

comments are summarized below and available at http://www.regulations.gov, Docket ID No. 

EPA-HQ-SFUND-1983-0002, with the support materials under document type “Public 

Submissions”, and at the information repositories at the following addresses: US EPA Region 1, 

Mailcode OSRR07-1, 5 Post Office Square, Suite 100, Boston, MA 02109-3919; Lithgow 

Public Library, 45 Winthrop St., Augusta, Maine 04330. 

EPA received two comments. One was critical of the remedy selected in 1989 as 

modified in 1994 and stated that the Site should not be removed from the NPL until it was 

completely clean. The other comment raised an issue not related to the proposed action of 

deleting the Site from the NPL. 

Summary of Comment No. #1: 

The comment voiced two concerns: The first questioned the effectiveness of relying on 

institutional controls to maintain the long-term protectiveness of the remedy; and the second 
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followed on the failure of institutional controls that “the public, in the form of the citizens of 

Augusta or the state of Maine” would have to pay for additional cleanup. Therefore, the Site 

should not be deleted until “it is completely clean.” 

Response: 

In questioning the effectiveness of institutional controls to maintain protectiveness and 

seeking a remedy that concludes with a “completely clean” site, the comment questions the 

adequacy of the selected remedy. The remedy was selected following two public comment 

periods in 1989 and 1994 for the Record of Decision and the Explanation of Significant 

Differences respectively. EPA believes that the remedy selected is protective of human health 

and the environment. The selected remedy has now been implemented, and all activities 

required under the remedy have been completed. The activities included the disposal offsite of 

30,000 tons of soil with the highest contamination levels, consolidating and covering the 

remaining contaminated soil onto a small area of the Site, removing PCB-oils from the 

groundwater, and restoring wetlands on the Site. Additionally, the activities completed at the 

O’Connor Superfund Site have satisfied those criteria that EPA has established for deletion of a 

site from the NPL. 

The comment also voiced the desire that the Site be completely clean before being 

deleted from the NPL. While this is an aspirational goal of the Superfund program, is not 

technically feasible to return every site to unlimited use and unrestricted exposure. For example, 

there are many municipal landfills where communities disposed of their waste for decades and 

many of these landfills are also Superfund sites. The costs for requiring local communities to 

pay for completely cleaning up these landfills so that they are available for any future use would 

be in the millions for each landfill. The technology and resources to achieve this goal of 

returning every site to pristine conditions are simply not available. 

Regarding the specific concern of relying on institutional controls, these are legal 

requirements that will prevent development of the property or prevent exposure to any wastes 

remaining on the property. The requirements are set forth in two documents. The first is the 

1992 Consent Decree between EPA and Central Maine Power (CMP) that will remain in effect 

as long as there is any waste remaining on the property that does not allow for unlimited use and 

unrestricted exposure at the Site. As required by this Consent Decree, EPA will continue to 

inspect the Site, continue to verify that the actions already taken remain protective of human 

health and the environment, and CMP will continue to be held responsible for the maintenance of 

the Site. The second document, called a Declaration of Restrictive Covenant, is recorded on the 

property records deed and it requires written approval be obtained from Maine Department of 

Environmental Protection (MEDEP) for any activities by CMP (or any future owner) that might 

interfere with the clean-up actions. For example, use of the groundwater or any excavations on 

the Site where there is remaining waste is prohibited. 

Finally, the selected remedy for the Site requires EPA to perform periodic reviews every 

five years to ensure that the remedy remains protective of human health and the environment. 
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Soil and groundwater will continue to be monitored by CMP to assure that conditions have not 

changed. 

Therefore, with the substantial amount of work that has been done at the Site, EPA and 

MEDEP still agree that the Site can be removed from the NPL. 

Summary of Comment No. #2: 

 

The comment voiced concerns about health issues for herself and others who lived or 

who continue to live near the O’Connor Site and stating a view that the number of cancers and 

other health issues suffered by residents nearby the Site concerned her. The comment also 

expressed dismay that she had not been contacted about the Site when she had lived nearby. 

Response: 

This comment did not address the substance of the proposed deletion nor whether the 

remedial goals have been accomplished. EPA completed a Five-Year Review of the Site in 2012 

and determined that the remedy as implemented remains protective of human health and the 

environment (this report and other five-year review reports are available on EPA’s website). 

Nonetheless, in response to the health concerns raised in the comment, a review of the 

Site record was made. EPA conducted a comprehensive risk assessment of the entire Site as part 

of the Remedial Investigation work in 1989. The risk assessment identified four potential 

exposure pathways that could pose an incremental cancer or other long-term risks over a lifetime 

of exposure to the maximum concentration levels measured on the Site: direct contact with, 

ingestion of, or inhalation of vapors from soils contaminated with PCBs and cPAHs; direct 

contact and ingestion with the PCB-contaminated sediments in the lagoons; ingestion of the 

contaminated groundwater from the bedrock system under the Site; and environmental risks to 

biota (i.e., fish, wildlife and plants) exposed to the contaminated soils, sediments, or surface 

waters at the Site may potentially exist from the presence of PCBs, lead, and aluminum. 

All PCB-contaminated soil and sediment above ten parts per million (the clean-up 

standard used for commercial property) were removed from the Site in 1997 and the lesser 

contaminated PCB-soil was consolidated and covered so that the direct contact pathway does not 

exist. The former lagoons on the Site were excavated and then restored as functioning wetlands. 

The institutional controls described in the previous response are currently prohibiting ingestion 

of groundwater and the two sampling events of fish tissue met the clean-up criteria. 

Regarding outreach to residents near the Site, EPA’s website notes that approximately 

fifty people lived within a quarter-mile radius of the Site when it was listed on the NPL in 1983. 

At that time all of these residential properties were to the west of the Site (and that remains the 

situation today). Groundwater flows away from these residential properties through the Site 

towards Riggs Brook. Sampling of five residential wells did not detect any site-related 

contaminants. Monitoring wells installed near these residential properties were always free of 
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contaminants found on the Site. Surface water and sediment samples collected from Riggs 

Brook met the clean-up criteria as did the fish samples. It is also noted that the prevailing wind 

direction is to the east, away from the residential properties west of the Site. 

The 1989 Record of Decision states that EPA kept the community and other interested 

parties apprised of the Site activities through informational meetings, fact sheets, press releases 

and public meetings. The Proposed Plan describing the proposed clean-up approach was mailed 

to all persons who were on the Site mailing list as well as to the local media outlets.