National Grid’s Remediation Contractor continued with site remediation activities, which included the delivery of construction materials, imported backfill material (stone and common fill), and construction equipment and supplies.  After the completion of the temporary enclosure relocation from Tent Position # 7 southwest to Tent Position # 8, Shallow Excavation Area remedial activities commenced at Tent Position #8 with off-site transport and disposal of impacted soils at approved and permitted disposal facilities. In addition, the NYSDEC approved cut and cap operations commenced in the southwest part of the Site. Placement of imported clean backfill material commenced within the Tent Position #8 Shallow Excavation Area and at the two foot thick cap in the southwest part of the Site.  Installation of temporary sheet piles continued at planned tent positions along the northern perimeter of the Site.  National Grid’s consulting engineer conducted noise and vibration monitoring activities, as necessary.

Maintenance of the decontamination areas, work zones, on-site gravel access roads, parking areas and material staging areas, the imported backfill material (i.e., clean fill) stockpile covers, the perimeter privacy screen, and soil erosion and sediment control (SESC) measures continued. Odor and dust suppression activities were conducted, as necessary. National Grid’s consulting engineers continued to monitor the site activities with the fixed base community air monitoring program (CAMP) equipment, as well as with noise and vibration monitors.

During the period from December 21, 2009 through December 27, 2009, six fixed base CAMP units and one portable CAMP unit were in-use and measured total volatile organic compounds (TVOC) and particulates (PM10). Fifteen-minute averages for both TVOC and PM10 data remained in the Operational Condition. Elevated PM10 measurements were reported on December 23, 2009; where these PM10 measurements were not associated with ground intrusive activities. Weekly Reports of the CAMP data can be found as a separate tab in the Weekly Report Archive section.

For the holiday week of December 28, 2009 through January 1, 2010, Tent Position #8 Shallow Excavation activities are scheduled to continue with off-site transport and disposal of impacted soils at approved and permitted disposal facilities. In addition, the NYSDEC approved cut and cap operations  are scheduled for completion in the southwest part of the Site. Delivery of imported clean backfill material (stone and common fill) and backfill material placement and compaction inside Tent Position #8 and at the two foot thick cap in the southwest part of the Site are scheduled to continue. On-site concrete demolition, crushing, and reuse operations are scheduled to continue at the Site, as necessary. Installation of temporary sheet piles will continue at tent positions along the northern perimeter of the Site, as necessary. Odor and dust suppression activities will be conducted as necessary. Work zone delineation, site maintenance activities, CAMP operation, and noise and vibration monitoring activities will continue.