Installing sheet pile to prepare for Position 4 excavation.

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. The Tent Position #2 Shallow Excavation and load-out remedial activities continued within the temporary fabric enclosure as well as the off-site transport of impacted material to approved and permitted disposal facilities.  Operation of the Vapor Management System (VMS) at Tent Position # 2 continued and worker health and safety monitoring activities were conducted at the site, as necessary.  The placement and compaction of imported backfill material continued within the southern part of the Shallow Excavation Area at Tent Position #2.   

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 engineer 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 July 13, 2009 through July 19, 2009, six fixed base CAMP units and one portable CAMP unit were in-use and measured TVOC and PM10. Fifteen-minute averages for both TVOC and PM10 data remained in the Operational Condition. On July 14, 2009 elevated PM10 concentrations were reported at the Portable Air Monitoring Station Site 1 (PAM 1) as a result of imported backfill material deliveries and not the result of ground intrusive activities. On Friday morning, July 17, 2009 and Saturday morning, July 18, 2009, elevated PM10 concentrations were reported as the the result of high moisture conditions and were not associated with ground intrusive activities. Additional detail is presented in the Weekly Reports of the CAMP data that can be found as a separate tab in the Weekly Report Archive section.

For the week of July 20, 2009 through July 24, 2009, Shallow Excavation Area remedial activities are scheduled to continue at Tent Position #2 with off-site transport and disposal of impacted soils at the approved and permitted disposal facilities. Delivery of imported clean backfill material (stone and common fill) will continue. On-going temporary fabric enclosure and VMS operation and maintenance will continue at Tent Position #2.  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.