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, completed the installation of the shallow steel sheet piling as well as construction of the Grout Plant working platform. The contractor commenced the construction of the Jet Grout Working Platform. The contractor also continued with the initial set-up of the waste management facility (WMF) and commenced the temporary fabric enclosure (i.e., tent) fabric repairs. The Remediation Contractor continued with the mobilization of personnel and equipment, and conducted 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) contractor were involved with the preparation of pre-mobilization submittals and scheduling 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 September 26, 2011 through October 2, 2011, six fixed base and one portable CAMP units 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. The Wednesday, September 28, 2011 elevated particulate matter measurement was the result of the Grout Plant asphalt pavement construction operations that were performed adjacent to FAM-1 and the site still remained in the operational condition. The Weekly Report that summarizes the CAMP data can be found as a separate tab in the Weekly Report Archive section.

For the week of October 3, 2011 through October 7, 2011, Phase 3 remediation construction activities are scheduled to continue at the Site. The remediation contractor is scheduled to complete the construction of the Jet Grout Working Platform. 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.