Reportable Concentrations of Oil and Hazardous Material in Groundwater

(1) For the purpose of determining whether a notification obligation exists under 310 CMR 40.0315, measured dissolved concentrations of any oil or hazardous material listed at 310 CMR 40.1600 shall be compared to the Reportable Concentration value in the reporting category that best characterizes the site under evaluation, as described below: (a) Reporting Category RCGW-1. Reporting category RCGW-1 shall be applied to all groundwater samples obtained: 1. within a Current Drinking Water Source Area; or 2. within a Potential Drinking Water Source Area. (b) Reporting Category RCGW-2. Reporting category RCGW-2 shall be applied to all groundwater samples that are not obtained from category RCGW-1 areas. (2) Reporting category RCGW-1 shall be selected whenever and wherever reasonable doubts exist over the selection of the appropriate groundwater Reportable Concentration category.