Funding for a removal action was approved on 13 April 2011. After completing the Fair Opportunity process, the cleanup contractor chosen was assigned a Task Order on 3 May 2011.
Below is a summary of the site investigation. See the PA/SI report or Action Memo for more details.
According to a report generated by a consultant for the property owner, while preparing to construct a residence at 12 Woodbury Court, ash and coal tar waste were discovered. Ash was visible on the surface, and coal tar encountered at a depth of approximately 8 feet. Analysis of near-surface soil by the property owner revealed the presence of a group of hazardous substances referred to as polyaromatic hydrocarbons (PAHs) at concentrations above the standards published in the Massachusetts Contingency Plan (MCP) for residential locations.
On 10 May 2010, a representative of the Massachusetts Department of Environmental Protection’s (DEP’s) Brownfields Program identified this site to the OSC and requested Removal Program assistance. As the footprint of the former Salem Gas Light Company appears to include both 12 Woodbury Court and the adjacent, City-owned Gonyea Park, the OSC made arrangements to sample both properties. The investigation was begun in July 2010, and consisted of collecting surface and subsurface soil samples to a maximum depth of three feet. In addition, the concentration of total volatile organic compounds (soil gas) was measured at each sample station in the field using a direct reading instrument. The three points with the highest concentrations nearest to adjacent residential properties were sent to a laboratory to identify the specific compounds present, and the concentration of each. An evaluation by DEP personnel revealed vapor intrusion is not an immediate concern, however DEP plans to carry out confirmation sampling under residences and paved areas.
Based on the lab results of tests run on soil, a second round of sampling was scheduled for the first week of January 2011 to better define the extent of contamination at Gonyea Park and 12 Woodbury Court, determine if other adjacent residential properties were impacted, and identify how much of the chromium detected present in the first round of sampling is trivalent chromium, and how much is the more toxic, hexavalent chromium. Analysis revealed that the chromium present at this site is the less toxic trivalent form.
Data generated from both sample events shows that one or more hazardous substances are present at a concentration above Massachusetts’ standards at 45 of 48 sample locations. On the land used as Gonyea Park, at least one state standard is exceeded at 40% of the surface samples analyzed; at one foot, 73%; two feet, 81%; and at three feet, 66%. In addition, while they do not exceed state standards, dozens of other hazardous substances have also been identified in soil at the site.
A Closure Memorandum dated 16 March 2011 formally documents the conclusion of the removal evaluation of this Site. It recommends that a removal action is appropriate because conditions at this Site meet the criteria in the National Contingency Plan (NCP) for initiating a removal action.
