Backfill Compaction in Tent #8

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 #8 with off-site transport and disposal of impacted soils at approved and permitted disposal facilities. In addition, the NYSDEC approved two-foot excavation cut operations in the southwest part of the Site were completed and pending the installation of the two-foot thick cap. Placement of imported clean backfill material and compaction continued within the Tent Position #8 Shallow Excavation Area of the Site.

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.

During the period from January 4, 2010through January 10, 2010, 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 January 8, 2010; where these PM10 measurements were not associated with ground intrusive activities and were measured after remedial actions were completed for the day. Weekly Reports that summarize the CAMP data and the elevated measurements can be found as a separate tab in the Weekly Report Archive section.

For the week of January 11, 2010 through January 15, 2010, Tent Position #8 Shallow Excavation backfill and compaction activities are scheduled to be completed. , Tent Position #8 will be relocated northeast to Tent Position #14. Tent relocation activities will include the temporary disassembly and staging of tent anchors and the vapor management system (VMS), temporary removal of the central panel, end panels and access doors, followed by the relocation of the two tent sections and replacement of the central panel, access doors, and end panels.  The temporary fabric enclosure supports, tent anchors, and VMS will be reset as the final phase of the tent position relocation. Odor and dust suppression activities will be conducted as necessary. Work zone delineation, site maintenance activities, and CAMP operation monitoring activities will continue.