85-2-501. Definitions. Unless the context requires otherwise, in this part the following definitions apply:

(1) "Aquifer" means any underground geological structure or formation that is capable of yielding water in usable quantities or is capable of recharge.

(2) "Aquifer test" means stressing an aquifer by removing or adding water at a known rate or changing the pressure by a known quantity and measuring the resultant change in hydraulic head for the purpose of determining the aquifer's hydraulic properties near the tested well.

(3) "Bureau" means the Montana state bureau of mines and geology provided for in 20-25-211.

(4) "Ground water" means any water that is beneath the ground surface.

(5) "Ground water area" means an area that, as nearly as known facts permit, may be designated so as to enclose a single and distinct body of ground water, which must be described horizontally by surface description in all cases and which may be limited vertically by describing known geological formations if conditions dictate vertical limits to be desirable.