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Home My WebLink AboutMiscellaneous - CHARLES STREET 4/30/2018 (2)I z� o �y pi P) rt n m � m a cn o �r cn m m nm Cr En a rt 0 s lv/�� / 1 `1 S U y L. vLGta.� l/ �. _r ly q-fl,45 AIA c RANSOM Environmental Consultants, Inc. August 12, 2005 Ms. Susan Sawyer Director, North Andover Health Department 400 Osgood Street North Andover, Massachusetts 01845 RE: Availability of Report Phase II Comprehensive Site Assessment Report and Phase III Remedial Action Plan Mineral Oil Dielectric Fluid (MODF) Release North Andover Junction Substation Charles Street North Andover, Massachusetts MA DEP Release Tracking No. 3-22031 Dear Ms. Sawyer: Project 021200 In accordance with the Massachusetts Contingency Plan (MCP) and on behalf of the Massachusetts Electric Company (MECo), Ransom Environmental Consultants, Inc. (Ransom) has prepared a Phase II Comprehensive Site Assessment (CSA) Report and a Phase III Remedial Action Plan (RAP) for the above -referenced property located in North Andover, Massachusetts. For the purpose of Phase II CSA and Phase III RAP, the Site is defined as the approximately 8,000 -square -foot area within the substation which was affected by a release of mineral oil dielectric fluid (MODF) from a foundation -mounted transformer (Transformer No. 1) located within the substation. The Site is identified by the MA DEP as Release Tracking Number (RTN) 3-22031. Pursuant to 310 CMR 40.1403(3)(e), this letter serves to notify the chief municipal officer of the availability of these reports. A copy of this letter has also been transmitted to Mr. Mark Rees, Town Manager, Town of North Andover. On August 15, 2002, MECO received reports of a power outage and discovered that Transformer No. I had overheated causing a release of MODF. MECo initially estimated that approximately 20 gallons of MODF was released from the top of the transformer; however, subsequent evaluations revealed that approximately 950 gallons of MODF had been released from the transformer. Polychlorinated biphenyls (PCBs) were detected in a sample of the released MODF at a concentration of 9 parts per million. Because a 2 -hour reporting condition, pursuant to 310 CMR 40.03 11(3), was triggered, on August 15, 2002 MECo notified the Massachusetts Department of Environmental Protection (MA DEP) of the release and RTN 3-22031 was assigned. The majority of MODF-impacted soil at the Site was removed through the excavation of approximately 230 cubic yards of soil as an Immediate Response Action (IRA), which was conducted during August, November, and December 2002; some MODF-impacted soil was inaccessible for fear of undermining the foundation of the substation control house. In addition, the source of the release, the damaged transformer, was removed. Additional response actions and subsequent investigations consisted of light ■ Brown's Wharf, Newburyport, Massachusetts 01950, Tel (978) 465-1822, Fax (978) 465-2986 200 High Street, Portland, Maine 04101, Tel (207) 772-2891 195 Commerce Way, Suite D, Portsmouth, New Hampshire 03801, Tel (603) 436-1490 2127 Hamilton Avenue, Hamilton, New Jersey 08619, Tel (609) 584-0090 1445 Wampanoag Trail, Suite 108A, East Providence, Rhode Island 02915, Tel (401) 433-2160 www.ransomenv.com Ms. Susan Sawyer Director, North Andover Health Department non -aqueous phase liquid (LNAPL) recovery, the installation of LNAPL extraction points, the advancement of soil borings, the installation of ground water monitoring wells, and the collection and chemical analysis of soil and ground water samples. Based on the results of preliminary response actions, the MODF impacts to soil and ground water are limited to the immediate vicinity of the control house foundation at the Site. Based on MODF LNAPL gauging data gathered to date, Ransom estimates that greater than %2 inch of MODF LNAPL is present on the ground water at a portion of the Site. To evaluate the risks posed by concentrations of extractable petroleum hydrocarbons (EPH) in soil and ground water at the Site, Ransom completed a Method 1 Risk Characterization. Although the exposure point concentrations of EPH remaining in soil at the Site are below their corresponding Method 1 standards, due to the presence of MODF LNAPL at a thickness of greater than 1/2 inch, a condition of "No Significant Risk" of harm to human health, public welfare, safety and the environment does not exist at the Site and additional response actions are necessary. The primary remediation goal for the Phase III Study is to recover MODF LNAPL, so as to reduce the mass of residual MODF in the environment that continues to serve as a source of contamination to soil and ground water. Through the removal of MODF LNAPL, the concentrations of EPH present in ground water and/or soil will be reduced. To achieve this goal, Ransom identified three applications and completed a detailed evaluation of the following remedial action alternatives (RAAs), which are expected to address the MODF LNAPL present at the Site: Alternative 1: Enhanced Active LNAPL Recovery and On -Site Ground Water Treatment Alternative 2: High Vacuum Extraction and Off -Site Disposal of LNAPL and Ground Water Alternative 3: Active LNAPL-Only Recovery Ransom used as criteria the comparative effectiveness, reliability, difficulty in implementation, costs, risks, benefits, timeliness, and non -pecuniary effects to evaluate these RAAs. Ransom concluded that Alternative 1 is the most feasible RAA for implementation at the Site. Copies of the Phase II CSA Report and Phase III RAP are available for public view at the Massachusetts Department of Environmental Protection (MA DEP) Northeast Region File Facility located at 35 Congress Street in Salem, Massachusetts. MA DEP files are open for public view by appointment only, Tuesday, Wednesday, and Thursday 9:00 a.m. to noon. You may contact the MA DEP Northeast Region File Facility at (978) 740-0809 for more information on reviewing MA DEP files. Ransom Project 021200 Page 2 P:\2002\021200\PhIII\boh-notification.doc August 12, 2005 M Ms. Susan Sawyer Director, North Andover Health Department Please contact me at (978) 465-1822 or Melissa Hall of MECo at (978) 725-1488 if you have any questions regarding the Phase II CSA or Phase III RAP. Sincerely, RANSOM ENVIRONMENTAL CONSULTANTS, INC. Lr L/ 1J0. Jlt cc: Melissa Hall, MECo MA DEP, Northeast Regional Office Ransom Project 021200 P:\2002\021200\PhIII\boh-notification.doc Page 3 August 12, 2005