Non-Potential Drinking Water Source Areas

Non-Potential Drinking Water Source Areas (NPDWSA) are regulatory in nature, representing one of many considerations used in determining the standards to which ground water must be cleaned in the event of a release of oil or hazardous material. NPDWSAs are not based on existing water quality and do not indicate poor ambient conditions. The Massachusetts Contingency Plan (310 CMR 40.0006) defines potentially productive aquifers and within those, non-potential drinking water source areas. Determination of NPDWSA is detailed in MassDEP policy WSC-97-701. These documents should be consulted for details regarding the regulatory framework in which this data was created and in which it should be interpreted. To the extent possible with available data, this coverage geographically delineates NPDWSAs. The data layer can and should be used as one reference for determining NPDWSA status and appropriate ground water standards. However, this data most likely contains errors of inclusion and exclusion. Conditions on the ground as specified in relevant regulations and policies supersede these delineations. Prior to June 2003, the NPDWSA designations were included in the Aquifers layer (for non-Cape Cod/Islands areas) and the now-deleted layer NPDWSACC (for Cape Cod/Islands). This layer is stored in the STATE library. The coverage and layer name is NPDWSA. The SDE layer name is NPDWSA_POLY.