About the Lower Liberty Hill Site

The Lower Liberty Hill Site is located in Gilford, New Hampshire, approximately three miles from a former MGP site on Messer Street in Laconia, New Hampshire. The former MGP site was owned and operated by numerous companies, including EnergyNorth Gas Inc., a predecessor company to KeySpan (now National Grid). The MGP site ceased operations in the early 1950’s after an explosion destroyed essential parts of the facility. The Laconia MGP site was known to KeySpan at the time it acquired EnergyNorth in 2000, and was the subject of environmental investigations and remediation required by the State of New Hampshire Department of Environmental Services (NHDES). The former MGP in Laconia was decommissioned around 1953, and at that time waste materials were disposed of at a gravel pit located along Liberty Hill Road, with the permission of the gravel pit owner. The property was later sold, subdivided and developed into four residences.

After learning of the Site in 2004, during meetings with the residential property owners in 2005, KeySpan representatives were told of “neighborhood talk” about the placement of material from the former MGP site (and possibly other sources) into the gravel pit. The residents agreed to NHDES testing of their drinking water wells, and the results of the testing did not indicate the presence of constituents associated with former MGP operations in the water. The NHDES was kept informed of the information KeySpan was gathering from its contacts with the residents. Based on this information, NHDES agreed that KeySpan undertake an investigation to determine the scope and delineation of the MGP-associated materials in the Liberty Hill area.

A Site Investigation was conducted in 2005 and 2006 and a Public Meeting presenting the results was held in Gilford in July 2006. During the investigation, samples of groundwater, soil, sediment, surface water, soil gas and indoor air were collected. Drinking water wells were tested at the properties in the vicinity of the Site. No contaminants were detected in any drinking water wells. Coal tar in soil and groundwater was identified on four properties on Liberty Hill Road (69, 77, 83 and 87 Liberty Hill Road). No coal tar or contaminated groundwater was found north of Liberty Hill Road. No significant current exposure pathways to coal tar were identified. However, the Site Investigation Report and NHDES public announcement stated that some soil and groundwater remediation would be required. Subsequently, NHDES requested that KeySpan conduct further investigations to determine whether site-related contaminants could impact Jewett Brook or the golf course on the other side of the Brook. That investigation was conducted in 2006 and 2007 and showed very limited impacts to the brook and virtually no impacts on the golf course side of the Brook. Subsequent studies, including the 2013 Pre Design Investigation, confirm the earlier assessments of possible offsite impacts.

In 2006, KeySpan acquired the four properties in order to facilitate remediation activities. The properties remain vacant and all of the structures have been demolished. They will be re-seeded and returned to a natural, vegetated state after the remediation.

KeySpan was acquired by National Grid in 2007. Liberty Utilities acquired National Grid’s business interests in New Hampshire in July 2012 and accepted responsibility for continuing the process of developing and implementing a remediation plan for the site. A Conceptual Remedial Design was completed and accepted by the NHDES in 2012 and a Pre-Design Investigation was completed in 2013 to further define the areas of contaminated soil. Remediation, primarily the removal of approximately 45,000 cubic yards of contaminated soil (after removal of approximately 55,000 cubic yards of clean soil at the surface and adjacent to the contaminated soil) is expected to begin in spring 2014.