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1/21/16 â GHD began Stage 1 of the Phase II Environmental Site Assessment (ESA) pursuant to the Phase II ESA Work Plan (Work Plan) prepared
by GHD and Ramboll Environ and dated January 21, 2016. The Phase II ESA was completed to characterize the Site and identify any areas that may require additional investigation and/or delineation (e.g., Stage 2) based on the assessment of risk to human health. Stage 1 of the Phase II ESA consisted of the advancement of 298 soil borings and associated soil sampling activities. Permanent monitoring wells were installed into 58 of the 298 soil borings and associated groundwater sampling activities were conducted. The Phase II ESA will be used to evaluate remedial strategies and be available to potential buyers of the property.
03/09/16 - 03/10/16 â GHD implemented a sediment investigation consisting of eight sediment sampling locations in the immediate vicinity of the GM stormwater discharge location (Outfall 010) into the Rock River. Three sediment samples from each of the eight locations (plus 3 duplicate samples for quality control purposes) were submitted for laboratory analyses.
03/14/16 â 03/16/16 â GHD completed Phase I ESA to identify recognized environmental conditions (RECs), as defined in ASTM International (ASTM) Standard E1527-13 (Standard), at the Site. This Phase I ESA was conducted to assist GM in conducting all appropriate inquiries into previous ownership and use of the Site to evaluate business environmental risk (BER), as defined in the Standard, for the Site. The Phase I ESA will be available to potential buyers of the property.
04/27/16 â GHD conducted second gauging event and included monitoring wells MWâ43S, MWâ52S, MWâ57S, MW-68S, MWâ73S, and MWâ79S due to the observed evidence of impacts during soil boring advancement in addition to MW-68S.
5/30/16 â 5/31/16 GM submitted Phase I ESA Report, Phase II ESA Report, Draft Sediment Investigation Report and Data Evaluation Report, and Sediment Investigation Data Report to WDNR.
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