EPA Proposes Update to Cleanup Plan for Dover Municipal Landfill Superfund Site
Public comments accepted until May 11, 2022
DOVER, N.H. (April 27, 2022) – Today, the U.S. Environmental Protection Agency (EPA) proposed an update to the agency's plan to clean up the Dover Municipal Landfill Superfund Site in Dover, New Hampshire. The proposed update is formally called an "Explanation of Significant Differences" (ESD) and ensures the cleanup will continue to be protective of human health and the environment.
EPA selected a comprehensive remedy through the site's Record of Decision (pdf) (17.8 MB) in 1991, and subsequent decision documents, to address risks to human health with two components – Source Control and Management of Migration.
The Source Control (SC) component consists of a multi-level groundwater extraction system. The Management of Migration (MOM) component addresses two groundwater contaminant plumes found to be migrating from the landfill. The MOM component consists of pumping and treating contaminated groundwater from the Southern Plume, while allowing the Eastern Plume to degrade naturally.
There are four proposed changes to the remedy in the ESD, including:
- Adding 1,4-dioxane as a Contaminant of Concern (COC) using the current state groundwater standard as the Cleanup Level;
- Modifying the Cleanup Level for Tetrahydrofuran in groundwater to reflect the current state groundwater standard, in accordance with EPA's risk standards;
- Clarifying the site-specific approach that will be used to determine that the Groundwater Cleanup Levels have been attained using a risk evaluation to document that residual risk is acceptable based on EPA's standards; that the groundwater restoration remedy is protective; and that groundwater restoration is complete; and
- Switching the terminology that is used for Groundwater Cleanup Levels from "Interim Cleanup Levels" to "Cleanup Levels," based on EPA's revised cleanup terminology.
The State of New Hampshire has reviewed the ESD and supports the proposed changes. EPA and the State of New Hampshire will evaluate public comments on the proposed changes before making the final decision to approve the ESD. The ESD will not fundamentally change the terms, scope, performance, or cost of EPA's plan to clean up the Dover Municipal Landfill site that was established in 1991, and then updated in 2004 and 2009.
The public can comment on the proposed update from Wednesday, April 27, through Wednesday, May 11, 2022, by following the steps listed below.
This ESD and supporting documentation shall become part of the Administrative Record for the Site. The ESD, the supporting documentation for the ESD, and the Administrative Record are available to the public for review online.
Comments on the ESD should be submitted no later than midnight on May 11, 2022, to:
Gerardo Millan-Ramos
U.S. EPA Region 1 Mail Code: 07-1
5 Post Office Square, Suite 100
Boston, MA 02109-3912
or Millan-Ramos.Gerardo@epa.gov
EPA no longer sends paper files to repositories, only on-line access to the Administrative Record is provided through the link above at the repositories. Individuals wishing to access the Administrative Record at a particular repository should check operating status, as some repositories may be closed.
For assistance with access or for questions, please contact:
SEMS Records & Information Center
U.S. EPA Region 1 - New England
5 Post Office Square, Suite 100 (mail code: 02-3)
Boston, MA 02109-3912
(617) 918-1440 (phone)
R1.Records-SEMS@epa.gov (email)
Dover Public Library
73 Locust Street Dover, New Hampshire 03820
Phone: (603) 516-6050
Background
The site is comprised of a 50-acre inactive landfill in Dover, New Hampshire. Owned and operated by the City of Dover from 1960 until its closure in 1980, the landfill accepted domestic and industrial waste. Buried materials include leather-tanning wastes, organic solvents, municipal trash and sludge from the Dover wastewater plant. Facility operations contaminated groundwater with volatile organic compounds (VOCs) and arsenic. In 1977, the state installed monitoring wells around the area and found that organic solvents were entering the groundwater, posing a potential threat to nearby residential wells and public water supplies for Dover and Portsmouth. The site was added to EPA's National Priorities List (NPL) in 1983.
For more information, please contact: Charlotte Gray, EPA Community Involvement Coordinator, gray.charlotte@epa.gov, Office: 617-918-1243