36.21.807 PREVENTION OF CONTAMINATION BY EQUIPMENT
(1) Preventive measures shall be performed to ensure against contamination from
equipment used to install or sample monitoring wells. Particular care must be
exercised when equipment used to install or sample monitoring wells in
contaminated environments is subsequently used to install production wells for
(2) When practicable or feasible, monitoring well installation should proceed from areas
with no or low levels of contamination to areas with higher levels of
(3) If contamination is detected during installation of a monitoring well, down-hole
equipment should be decontaminated before use on another well or at another
site. Appropriate methods of cleaning or decontamination will depend upon the
level and type of contaminants, but may include steam cleaning, rinsing with
uncontaminated water, or thorough cleaning with surfactants and deionized
(4) Contamination of down-hole equipment on the drill rig itself by hazardous materials requires thorough
cleaning to prevent transport of hazardous contaminants to other locations. On-site
decontamination may be necessary under particularly hazardous conditions.
History: Sec. 37-43-202, MCA; IMP, Sec. 37-43-202, MCA; NEW, 1988 MAR p. 2503, Eff. 11/24/88.