There are three criteria in Maine for determining when closure is appropriate for a petroleum site. These criteria are achieved when the limits of technology have been met which may mean the cost effectiveness of the solution is not practical or feasible, the human health risks have been eliminated, or the cleanup goals have been met. CEG's closure strategy focuses on one or more of these criteria.
The first step to evaluate the closure strategy is to ensure that the site has been properly categorized into one of the Maine Department of Environmental Protection's four cleanup criteria. The second step, if necessary, is to begin remedial efforts. CEG typically pilot tests remediation techniques on any site prior to full scale design, installation, or operation. Following the results of the pilot testing, CEG will evaluate the data generated to design an effective system or to evaluate other remedial techniques.
The amount and type of field work is specific to each site and includes: conducting verification sampling of monitoring wells, homeowner water supply wells and landspread soil; water supply well replacement; well abandonment; and decommissioning remedial systems.
Similar field work tasks within a particular region are scheduled in a manner that minimizes travel time and costs for mobilization of equipment. Projects on the closure list include sites from each of the four Maine DEP regional offices in Portland, Augusta, Bangor, and Presque Isle.
The Maine DEP also requested that CEG prepare a manual outlining the steps and methods for completing site closures. The intent of the manual was to provide the Maine DEP project managers a consistent and thorough method for completing site closures.
