PUBLIC HEALTH ASSESSMENT ADDENDUM
SOMERSWORTH MUNICIPAL LANDFILL
SOMERSWORTH, STRAFFORD COUNTY, NEW HAMPSHIRE
This public health assessment addendum is intended to updated the Somersworth Sanitary Landfill Health Assessment of April 12, 1989. This addendum is being performed in connection with a forthcoming Environmental Protection Agency (EPA) Record of Decision (ROD) for the site.
Based upon the most recent information reviewed for the Somersworth Sanitary Landfill Site, the New Hampshire Division of Public Health Services (NH DPHS) and ATSDR believe that this site poses an indeterminate public health hazard. The limited available data do not indicate that humans are being or have been exposed to levels of contamination that would be expected to cause adverse health effects. However, data or information are not available for all environmental media to which humans may be exposed. A data gap exists for the evaluation of methane as an explosive hazard. Risks associated with this pathway cannot be assessed without additional data.
ATSDR and NH DPHS recommend that residential wells in the vicinity of the landfill continue to be monitored for VOCs on a regular basis in order to document water quality. Secondly, it is recommended that soil gas sampling be conducted to assess the potential explosive hazard risks to buildings surrounding the landfill.
The data and information in the public health assessment for the Somersworth Sanitary Landfill site have been evaluated by ATSDR's Health Activities Recommendation Panel (HARP) for appropriate follow-up with respect to health actions. The panel determined that no follow-up health actions are indicated at this time.
The Public Health Action Plan (PHAP) for the Somersworth Sanitary Landfill site, which
contains a description of actions to be taken by NH DPHS and NH DES at and in the vicinity of
the site, has been developed. NH DES will continue to sample residential wells in the area of the
landfill on a periodic basis to document water quality. NH DPHS will evaluate water quality
data to determine whether exposure to contaminated water poses a health risk. ATSDR will
provide an annual follow-up to this PHAP, indicating the status of the action presented in this
The following statements supplement the indicated sections or are additions to the Somersworth Sanitary Landfill Health Assessment of April 12, 1989 (Appendix A) and intended to update that previous health assessment.
A. Site Description and History
A draft Feasibility Study (FS) for the Somersworth Sanitary Landfill Site was released in February 1991 (1). Additional sampling has been conducted at the site by the Settling Parties, the State of New Hampshire Department of Environmental Services and the Environmental Protection Agency between the years 1989-1992. The results of the additional air and groundwater sampling are reported in the Remedial Investigation (RI) Data Gathering Report (2) and documents prepared by the state of New Hampshire (3). This Addendum to the Health Assessment (HA) is being performed to coincide with a forthcoming Record of Decision (ROD).
B. Actions Implemented During the Health Assessment Process.
The NH DES has conducted residential well sampling in the area of the landfill. The results of the analysis of these samples have been evaluated by NH DPHS. The NH DPHS has conducted environmental community health education by informing the owners of these residential wells of the results of their evaluation with respect to environmental public health.
C. Site Visit
A site visit to the Somersworth Sanitary Landfill was conducted by Rosalyn Lee and Susanne Simon of ATSDR and an EPA staff member on July 7, 1992. Site conditions were similar to those described in the original public health assessment (4). In portions of the western side of the landfill trees and brush are accepted for disposal and recycling. To the east of the "stump dump" lies a scrap metal and appliance disposal area. Large appliances such as refrigerators were located in this area. Further east were several piles of assorted wastes. Materials in the piles included construction and transportation debris such as bricks, cement, and asphalt. A fence now separates the recreation areas from the landfill. Trespassers, however, can still gain access to the landfill through the Blackwater Road entrance. Many people were observed using the recreation facilities on the eastern side of the site. These facilities include a baseball field, and paved tennis and basketball courts.
D. Demographics, Land Use and Natural Resource Use
The Somersworth City Engineer has indicated that with the exception of approximately three municipal wells which are not located in the immediate vicinity of the site, most private wells are not in use as most residences have been hooked up to the municipal water supply. He indicated that three residential wells still in use are located approximately 1100, 2000, and 3300 feet west of the site along Blackwater Road (3). Recent communication with the DES Remedial Project Manager for the site revealed that there currently are five known residential wells in use in this area (11). Groundwater within the aquifer flows regionally in a westerly, then west northwesterly direction across the landfill towards Peter's Marsh Brook and the surrounding wetlands. The plume of contamination is not expected to impact these residential wells (3).
Surface water runoff in the vicinity of the landfill drains into Peter's Marsh Brook which lies along the western edge of the landfill. This small stream runs along the edge of the landfill and into the wetlands. It does not appear large enough to support a fish population for recreational fishing. Recreational fishing does reportedly occur approximately 2000 feet north of the edge of the landfill in a pond created by the convergence of Peter's Marsh Brook and Tates Brook (5).
E. Health Outcome Data
The Health Officer for the City of Somersworth has indicated that, to his knowledge, there are no known public health concerns or complaints by area residents regarding the Somersworth Sanitary Landfill Site at the present time (7).