Boston, Mass. -- EPA has completed its Fifth Five-Year Review Report on the remedy implemented at the Auburn Road Landfill Superfund Site in Londonderry, N.H.
The primary purpose of each five year review is to determine whether the selected remedy at a Superfund site is protective of human health and the environment. In addition, the five year review will identify any deficiencies, and recommend action(s) necessary to address them.
The fifth five-year review for the Auburn Road Landfill Superfund Site concluded that the remedy implemented at the Site currently protects human health and the environment in the short-term because: (a) installation of a municipal water supply currently provides drinking water to residences in the affected area, and (b) implementation of institutional controls through establishment of a Groundwater Management Zone (GMZ) currently provides notice on groundwater use restrictions at and near the Site.
However, the selected cleanup remedy for the Site predicted a cleanup time for arsenic in groundwater of five years after capping of the three on-site disposal areas which occurred in 1996. This 5-year period has lapsed, yet arsenic concentrations in groundwater have not attained the required, interim cleanup level (ICL) of 10 ppb.
In order for the remedy to be protective in the long-term, the following actions need to be taken: (a) schedule a meeting including EPA, New Hampshire Department of Environmental Services (NHDES), United States Geological Survey, and the settling parties to discuss the required follow-up actions necessary to expedite the time to reach groundwater cleanup levels, and further investigate groundwater interactions with nearby surface waters/sediments; (b) expand the institutional control boundary north of Auburn Road; and (c) gather additional groundwater data in order to reassess the potential vapor intrusion pathway, and achievement of ICLs.
The Site consists of approximately 180-acres of property owned by the Town of Londonderry; the western most portion of the Site consists of property occupied by the Whispering Pines Mobile Home Village. The Site is bordered by Auburn Road and residences to the west, Old Derry Road and residences to the south, an unnamed stream and wetland areas to the east, and Whispering Pines Pond and the mobile home park to the north/northeast.
Although the entire Site consists of approximately 180-acres, the three disposal areas only occupy approximately 12 acres. The disposal areas received a mix of domestic wastes and various hazardous wastes beginning in 1965 until the landfills were closed in 1980. The northernmost of the three disposal areas is the “Old Town Dump” which is the oldest of the disposal areas; the second disposal area is the “Tire Pile” area which is slightly larger than the “Old Town Dump”; and the “Solid Waste Landfill” is the third disposal area. At one time, a septage disposal area existed to the north of the solid waste dump area. The Town excavated that area and the material was consolidated in the solid waste area in 1993. In 1996, a cover was installed over the disposal areas. The cover consists of a modified Resource Conservation and Recovery Act (RCRA)-type C cap, and is roughly 4 feet thick with a geotextile impermeable membrane, clay liner and a vegetated (grass) cap.
A copy of the Fifth Five-Year Review Report is available for download on the EPA New England web site at: www.epa.gov/region1/superfund/sites/auburnroad
EPA technical reports and documents about cleanup activities are available for review at the Site repositories located at:
Leach Public Library, 276 Mammoth Road, Londonderry, NH 03053
EPA Records Center, One Congress Street, Boston, MA 02114 [Phone: (617) 918-1440 (by appointment)]