| The Somersworth Sanitary Landfill Site (Somersworth site) is a former landfill in southern New Hampshire that is on the National Priorities List (NPL). The landfill was closed in 1981 and has had a groundwater monitoring network since the 1980s. Groundwater remedies were installed by 2001, and the site is currently in the long-term monitoring phase of operation and maintenance (O&M). U.S. EPA Region 1 requested a review of the Somersworth site groundwater monitoring plan. Site monitoring data was reviewed and statistical and heuristic evaluations were performed using the Monitoring and Remediation Optimization System software (MAROS) in 2007. Inputs, results and recommendations for the groundwater monitoring network, including the results based on the MAROS analysis, were reviewed. |