CRITERIA FOR ASSESSING WELL VULNERABILITY

Subpart 1. Department determination. The department shall use the criteria specified in this part to assign priority and notify a public water supplier in writing that a wellhead protection plan must be prepared for an existing well. Subp. 2. Well vulnerability criteria. A public water supply well is vulnerable if: A. the well water contains ten milligrams per liter or more nitrate plus nitrite nitrogen; B. the well water contains quantifiable levels of pathogens as defined in part 7040.0100 , subpart 26, or chemical compounds that indicate groundwater degradation as defined in Minnesota Statutes, section 103H.005 , subdivision 6; C. the well water contains one tritium unit or more when measured with an enriched tritium detection method; or D. an enriched tritium analysis of the well water has not been performed within the past ten years; and (1) information on the well construction is not available; or (2) the geological material from the land surface to where the groundwater enters the public water supply well is: (a) fractured bedrock; (b) solution weathered bedrock; (c) sandstone bedrock; (d) unconsolidated material 0.062 millimeters (fine sand) or larger; or (e) a combination of the materials specified in units (a) to (d).