National Grid’s contractor and Project Team continued to construct the composite 120-foot deep dense non-aqueous phase liquid (DNAPL) Migration Barrier Wall (i.e., jet grouted barrier). The contractor continued Site preparations for the 2012 Production Jet Grouting Program, final stage of power installation for Grout Plant and installation of meters for the WMF, and general maintenance and security activities at the Site. The National Grid Project Team continued evaluating the results of the 2011 Pre-Production Jet Grouting Program and is currently developing the field parameters and schedule for the 2012 Production Jet Grouting Program. The contractor managed and disposed of the Pre-Production Phase generated water off-site at a licensed and permitted disposal facility.

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 January 16, 2011 through January 22, 2012, six fixed base 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. 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 week of January 23, 2012 through January 26, 2012, the contractor is scheduled to commence the 2012 Production Jet Grouting Program. The contractor will finalize installation of the power drop for the Grout Plant, as well as perform general maintenance activities and housekeeping at the Site, as necessary. Dust suppression activities will be conducted, as necessary.