1. (1) The department will review and evaluate all official ground water test results. Official ground water test results will be classified as either:

   1. (a) negative detection;
   2. (b) positive detection below the adopted standard;
   3. (c) positive detection which meets or exceeds the adopted standard;
   4. (d) positive detection for which there is no standard.
2. (2) Negative detections will be entered into the departments ground water data base and reported to the affected person.
3. (3) Positive detections lower than 50% of the standard will be entered into the departments database, reported to the affected person, and will be noted as a well to be resampled to observe changes in agricultural chemical concentrations in the aquifer. The department will prepare a SMP under 80-15-212 (1) (b) or (c) , MCA, if additional monitoring demonstrates a scientifically-validated increase in agricultural chemical residues in ground water or if an agricultural chemical has migrated from the point of detection.
4. (4) Positive detections that meet or exceed 50% of the standards will be reported to the affected persons and resampled to confirm the results.

5. (5) If positive detections are confirmed, the following steps will be taken:

   1. (a) enter in ground water database;
   2. (b) intensify monitoring in the immediate vicinity, to identify the source(s) of impairment or degradation and to determine the extent of impairment or degradation;
   3. (c) conduct investigation into the possible cause of impairment or degradation;
   4. (d) prepare a specific management plan as provided in 80-15-212 , MCA; and
   5. (e) initiate any necessary enforcement monitoring.

6. (6) An unofficial test result may be used to:

   1. (a) initiate monitoring in a particular area;
   2. (b) notify local and state agricultural, environmental and health officials.

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.