2.Determination of ground water quality. The commissioner and the Department of Agriculture, Conservation and Forestry shall delineate the primary recharge areas for all sand and gravel aquifers capable of yielding more than 10 gallons per minute. Utilizing existing water supply information and well drilling logs, the commissioner and the Department of Agriculture, Conservation and Forestry shall determine depth to bedrock, depth to water table, surficial material stratigraphy and generalized ground water flow directions of the aquifers. The commissioner and the Department of Agriculture, Conservation and Forestry shall also determine the extent and direction of contamination plumes originating from distinct sources within each area studied. The primary recharge areas, flow directions and contamination plumes are to be shown on maps of a scale of 1:50,000. [1989, c. 890, Pt. A, §40(AFF); 1989, c. 890, Pt. B, §22(AMD); 2011, c. 657, Pt. W, §5(REV).]