Removal Activities for Tent Position #3

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. Shallow Excavation Area remedial activities were completed at Tent Position #4 with off-site transport and disposal of impacted soils at approved and permitted disposal facilities. Further, placement of imported clean backfill material continued within the Tent Position #4 Shallow Excavation Area. On-site concrete crushing operations commenced and temporary steel sheeting installations continued in the southwest corner 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 September 21, 2009 through September 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. No elevated TVOC or PM10 measurements were reported for the weekly CAMP monitoring period. Weekly Reports of the CAMP data can be found as a separate tab in the Weekly Report Archive section.

Backfill at Tent Postion #4

For the week of September 28, 2009 through October 2, 2009, delivery of imported clean backfill material (stone and common fill) and backfill material placement inside Tent Position #4 will continue.  After Tent Position #4 backfill placement activities are completed, the temporary fabric enclosure and VMS system will be relocated to the west from Tent Position #4 to Tent Position #5.  Tent Position # 5 Shallow Excavation activities are scheduled to commence after completion of the tent move, where impacted soils will be excavated, transported and disposed off-site at approved and permitted disposal facilities. On-site concrete crushing operations are scheduled to continue this week. Temporary steel sheeting installations are scheduled to continue at Tent Positions #6 and #7. 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.