August 4, 2001
NEIGHBORHOOD NOTICE

Dear Resident,

The Air Force Center for Environmental Excellence (AFCEE) is committed to protecting public health. As part of this commitment, we wish to provide you with an update on the cleanup system operations in your neighborhood.

Storm Drain 5 Groundwater Plume Update

The Storm Drain-5 North and South groundwater plume boundaries have been updated using data collected during July 2000. The previous SD-5 North (SD-5N) plume boundary was drawn using data collected in August 1997 while the previous SD-5 South (SD-5S) plume boundary was drawn using data collected in May 1999 (refer to Figure 1). The SD-5N plume has been reduced in size by pumping and treating contaminated groundwater through the SD-5N treatment system (operational since August 1997). The SD-5S plume has been reduced in size by pumping and treating contaminated groundwater through the two recirculating wells (operational since June 1999) and one of the two extraction wells on Hooppole Road (operational since January 2000).

Since June 1999, two recirculating well treatment systems, one located below Hillside Avenue at the intersection with Highland Street and one on Wheeler Road, have been cleaning contaminated groundwater from the SD-5S groundwater plume. From June 1999 through December 31, 2000, the SD-5S recirculating wells pumped and treated a total of 84 million gallons of contaminated groundwater. From January 1, 2001 through June 30, 2001, the SD-5S recirculating well at Hillside Avenue pumped and treated a total of 15.7 million gallons of contaminated groundwater.

TCE concentrations detected in samples collected from the Hillside Avenue recirculating well treatment system have decreased over time, and currently are detectable above the TCE maximum contaminant level (MCL) of 5 parts per billion (ppb). The MCL is the maximum concentration of a given contaminant allowed in drinking water under the federal Safe Drinking Water Act. The SD-5S system currently pumps and treats 60 gallons per minute of contaminated groundwater. Continued operation and monitoring of this system and surrounding monitoring wells will help to ensure that the Hillside Avenue treatment system is effectively capturing and treating the remaining portions of the SD-5S groundwater plume located near this system.

TCE concentrations detected in samples collected from the Wheeler Road recirculating well treatment system have decreased over time and, since August 2000, have not been detectable when analyzed. Since July 1999, no detections of TCE above its MCL (5 ppb) have been measured in samples collected from groundwater monitoring wells located upgradient (the area from which groundwater flows) of the Wheeler Road system. In addition, no contaminants have been detected in samples collected from groundwater monitoring wells located immediately downgradient (the area toward which groundwater flows) of the Wheeler Road system since December 1999.

Based on the lack of contamination detected in the Wheeler Road system, AFCEE recommended to the U.S. Environmental Protection Agency (EPA) and the Massachusetts Department of Environmental Protection (DEP) in mid-December 2000 that the Wheeler Road recirculating well treatment system be shut down temporarily. At that time, AFCEE also recommended sampling additional groundwater monitoring wells near the Wheeler Road area. EPA and MassDEP reviewed AFCEE’s proposal and agreed to keep the well temporarily shut down. This well currently is shut down and groundwater monitoring continues to be performed in order to ensure that groundwater near this system remains clean.

Since January 2000, two extraction wells located on Hooppole Road have been cleaning up a portion of the Chemical Spill 10 (CS-10) groundwater plume (formerly known as the Trichloroethylene plume) and the remaining portion of the SD-5S groundwater plume. Through June 30th, 2001, the SD-5 South and CS-10 Hooppole Road wells together have pumped and treated a total of 120 million gallons of contaminated groundwater.

AFCEE officials will hold an informational poster session to update the public about Ashumet and Johns Ponds and MMR-related cleanup work. Numerous MMR cleanup topics will be presented on posterboards and will include the results of the CS-10 investigative work performed last summer. Additionally, informational updates on the Storm Drain 5 North and South and Fuel Spill 1 groundwater plumes, the Quashnet bogs, and the Storm Drain 2 project also will be presented on posterboards. Updated information on Ashumet Pond phosphorus and the planned phosphorus inactivation project for this year also will be available. The meeting will be held in an informal posterboard setting, allowing for direct interaction with AFCEE, EPA and MassDEP project managers, program engineers and scientists.