1 

### 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’C onnor Superfund Site (Site) was published in the Federal Register on March 12, 2014 (Vol. 79, No. 48, page s 13967-13968). The publication of this notice was intended to inform the public th at 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 No tice of Intent to Dele te was April 11, 2014. Two written comments were received; therefor e, EPA has prepared this Responsiveness Summary. In addition, all public comments were c onsidered 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 th e 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 mate rials under document type “Public Submissions”, and at the information repositorie s at the following addr esses: 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 s hould 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 que stioned the effectiveness of relying on

institutional controls to main tain the long-term protectivenes s of the remedy; and the second2 followed on the failure of institutional controls th at “the public, in the form of the citizens of Augusta or the state of Maine” would have to pa y for additional cleanup. Therefore, the Site

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

Response:

In questioning the effectiveness of institutiona l controls to maintain protectiveness and seeking a remedy that concludes with a “comple tely clean” site, the comment questions the adequacy of the selected remedy. The reme dy was selected following two public comment periods in 1989 and 1994 for the Record of Decision and the Explan ation 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. Th e activities included the disposal offsite of 30,000 tons of soil with the highest contamina tion 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 criter ia that EPA has established for deletion of a

site from the NPL.

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

deleted from the NPL. While this is an as pirational goal of the Superfund program, is not technically feasible to return ev ery site to unlimited use and unrest ricted exposure. For example, there are many municipal landfills where communiti es 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 thes e landfills so that they are avai lable 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 cond itions are simply not available.

Regarding the specific concern of relying on institutional controls, these are legal requirements that will prevent de velopment of the property or pr event exposure to any wastes remaining on the property. The requirements are se t forth in two documents. The first is the

1992 Consent Decree between EPA and Central Main e Power (CMP) that will remain in effect as long as there is any waste remaining on the pr operty 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 act ions 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 Declarati on of Restrictive Covenant, is recorded on the property records deed and it requires written a pproval be obtained from Maine Department of Environmental Protection (MEDEP) for any activiti es by CMP (or any future owner) that might interfere with the clean-up actions. For exampl e, use of the groundwater or any excavations on the Site where there is remaining waste is prohibited.

Finally, the selected remedy for the Site re quires EPA to perform periodic reviews every five years to ensure that the remedy remains protective of human health and the environment.3 Soil and groundwater will continue to be monitored by CMP to a ssure that conditions have not changed.

Therefore, with the substantia l amount of work that has be en 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 i ssues for herself and others who lived or

who continue to live near the O’Connor Site a nd 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 contac ted about the Site when she had lived nearby.

Response:

This comment did not address the substan ce of the proposed deletion nor whether the remedial goals have been accomplished. EPA comp leted a Five-Year Review of the Site in 2012 and determined that the remedy as implemente d remains protective of human health and the environment (this report and other five-year review reports are av ailable on EPA’s website).

Nonetheless, in response to the health concer ns raised in the comme nt, a review of the Site record was made. EPA conducted a comprehensiv e risk assessment of the entire Site as part of the Remedial Investigation work in 1989. The risk assessment id entified four potential exposure pathways that could pose an incrementa l 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 so ils 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 syst em under the Site; and environmental risks to biota (i.e., fish, wildlife and plan ts) 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 th e Site in 1997 and the lesser

contaminated PCB-soil was consolidated and covere d so that the direct contact pathway does not exist. The former lagoons on the Site were excava ted and then restored as functioning wetlands. The institutional controls described in the prev ious response are curren tly prohibiting ingestion of groundwater and the two sampling events of fish tissue met th e clean-up criteria.

Regarding outreach to residents near the Si te, 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 prope rties through the Site towards Riggs Brook. Sampling of five reside ntial wells did not de tect any site-related contaminants. Monitoring wells installed near th ese residential properties were always free of4 contaminants found on the Site. Surface water and sediment samples collected from Riggs Brook met the clean-up criteria as did the fish samp les. 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 info rmational meetings, fact sheets, press releases and public meetings. The Proposed Plan descri bing 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.