17.38.513    CHEMICAL TREATMENT OF WATER

(1) Except as provided in (3), water haulers shall dose each load of water with enough chlorine to provide a free chlorine or total chlorine residual of at least 0.4 parts per million (ppm), not to exceed 4.0 ppm, at the time the water hauling equipment is filled and at the time the water is delivered to the receiving system. Water haulers shall use department-approved methods to monitor the chlorine residual concentration.

(2) Water haulers shall monitor each load of water, and shall record chlorine residual results on department-approved forms. Haulers shall retain the records of chlorine residual results for each load and shall provide the records to the department upon request. Chlorine residual records must be retained for ten years, as required by 40 CFR, Part 141.33, which is incorporated by reference in ARM 17.38.234. By the tenth of the month following a delivery, haulers shall report the following to the department on department-approved forms:

(a) one chlorine residual result for each day water is delivered, taken from the load with the lowest monitored residual result; and

(b) for days that a hauler obtains and delivers water from multiple public water suppliers, one chlorine residual result per supplier per day, taken from the loads with the lowest monitored residual result.

(3) Water haulers using an approved chloraminated source of water shall monitor, record, and report residuals as required in (1) and (2), but are not required to adjust total chlorine levels.

 

History: 75-6-104, MCA; IMP, 75-6-104, MCA; NEW, 1979 MAR p. 38, Eff. 1/26/79; TRANS, from DHES, 1996 MAR p. 1499; AMD, 2009 MAR p. 1794, Eff. 10/16/09; AMD, 2011 MAR p. 1545, Eff. 8/12/11; AMD, 2024 MAR p. 253, Eff. 2/10/24.