Minnesota Administrative Rules

4725.3725 CHEMICAL TREATMENT AND REHABILITATION.

Subpart 1.

Treatment chemicals.

Chemicals placed in a well or boring to increase the yield, remove or treat contaminants or objectionable tastes or odors, or rehabilitate the well or boring must meet the requirements of ANSI/NSF Standard 60-2016 as determined by a person accredited by ANSI. Sodium or calcium hypochlorite may be used if registered by the United States Environmental Protection Agency according to the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), section 3(c)(7)(A), as an antimicrobial pesticide for use in potable water. Treatment chemicals must be neutralized or removed from the well, boring, and any connected piping systems prior to use of the well or boring. This part does not apply to chlorine or other treatment chemicals added to a water distribution system, or to a drilling additive used according to part 4725.2950.

Subp. 2.

Treatment with an acid.

A.

Before treating a well or boring with an acid, all confined spaces enclosing the well or boring must be blown out with fresh air before entry and a supply of fresh air must be provided during occupancy. When there is a question of adequate fresh air supply, a self-contained breathing apparatus must be worn.

B.

The pH (hydrogen ion concentration) of the water must be measured prior to treatment.

C.

The well or boring must not be placed back into service until the pH is within one pH unit of the pretreatment value.

Statutory Authority:

MS s 103I.101; 103I.111; 103I.205; 103I.221; 103I.301; 103I.401; 103I.451; 103I.501; 103I.525; 103I.531; 103I.535; 103I.541; 103I.621

History:

33 SR 211; 45 SR 986

Published Electronically:

April 30, 2021