National Grid’s Remediation Contractor and Project Team continued to plan for the composite 120-foot deep dense non-aqueous phase liquid (DNAPL) Migration Barrier Wall (i.e., jet grouted barrier) installation. The Remediation Contractor continued Phase 3 remediation construction activities at the Site. The contractor continued general maintenance of the Site and completed the construction of the Jet Grout Working Platform. The contractor mobilized personnel and equipment and conducted Site preparations including the construction of the waste management facility (WMF), and repairs to the temporary fabric enclosure (i.e., tent). The Remediation Contractor continued with Site preparations and detailed layout efforts for the Phase 3 Composite 120-foot deep DNAPL Migration Barrier Wall Installation project. The jet grouting contractor (JGC) and waste management and emergency response (WM/ER) contractors prepared pre-mobilization submittals and scheduled activities for the project.

Maintenance of the imported backfill material (i.e., clean fill) stockpile covers 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 community air monitoring program (CAMP) equipment.

During the period from October 3, 2011 through October 9, 2011, six fixed base units and one portable CAMP unit were in operation and measured total volatile organic compounds (TVOC) and particulates (PM10). Fifteen-minute averages for both TVOC and PM10 data remained in the Operational Condition. There were no elevated readings for TVOC or PM10 for this monitoring period. The Weekly Report that summarizes the CAMP data can be found as a separate tab in the Weekly Report Archive section.

For the holiday week of October 10, 2011 through October 14, 2011, Phase 3 remediation construction activities are scheduled to continue at the Site. The remediation contractor is scheduled to complete the construction of metal sleeves within the Jet Grout Working Platform, and commence assembly of the Jet Grout Plant system. The contractor will continue with the mobilization of personnel and equipment, and will continue to conduct Site preparations including the construction of the waste management facility (WMF), and fabric repairs to the temporary fabric enclosure (i.e., tent).. In addition, the contractor will conduct general maintenance activities and housekeeping at the Site, as necessary. Dust suppression activities will be conducted, as necessary.