1. (1) Factors that may be used in establishing priority for selection of sampling sites include, but are not limited to:

   1. (a) local cropping practices;
   2. (b) agricultural chemical use patterns;
   3. (c) soil characteristics;
   4. (d) depth to water table;

   5. (e) ground water usage:

      1. (i) public or private drinking water supply;
      2. (ii) non-potable use;
   6. (f) existing water quality;
   7. (g) previous detections of agricultural chemical residues in ground water;

   8. (h) the potential for adverse impact of impaired or degraded ground water on human health or the environment:

      1. (i) number of wells per unit area;
      2. (ii) volume of ground water used for human consumption per unit area.
   9. (i) impairment or degradation of irrigation water;
   10. (j) agricultural chemical user activities which may lead to ground water impairment or degradation;
   11. (k) suspected misuse of chemicals, violation of Title 80, chapter 15, MCA, or violation of a SMP.
2. (2) The department will consider seasonal changes in ground water recharge and flux and irrigation scheduling when determining appropriate times to sample water.
3. (3) The department will re-evaluate site prioritization based on new or updated information.

Authorizing statute(s): Sec. 80-15-105, MCA

Implementing statute(s): Sec. 80-15-202 and 80-15-203, MCA

History: NEW, 1990 MAR p. 2244, Eff. 12/28/90.