Minnesota Administrative Rules

4725.5825 PUBLIC WATER-SUPPLY WELLS.

Subpart 1.

Requirements.

In addition to the requirements of parts 4725.2010 to 4725.5650, a water-supply well used to provide water for a noncommunity or community water system must comply with the requirements in subparts 2 to 6.

Subp. 2.

Notification of drilling required.

The licensee must notify the commissioner of the proposed construction starting time of a community or noncommunity public water-supply well 24 hours in advance of beginning construction. The information may be placed on the notification form required in part 4725.1820 or may be reported by telephone, facsimile, or in person. The notification must be made between 8:00 a.m. and 4:30 p.m., Monday through Friday, excluding holidays.

Subp. 3.

Additional disinfection or development required.

A public water-supply well constructed in an unconsolidated formation using a rotary or other method that creates an annular space and uses a bentonite drilling fluid, in addition to the disinfection requirements of part 4725.5550, must be either:

A.

disinfected upon completion of drilling and prior to grouting by placing a minimum 200 mg/l free chlorine solution in the bottom of the well and circulating the solution both inside the casing and in the annular space to the established ground surface for a minimum of 30 minutes; or

B.

developed by agitating and forcing water out of the screen for a minimum of one hour.

Subp. 4.

Grouting required.

A public water-supply well constructed with a method that creates an open annular space must be grouted as specified in part 4725.3050 from within ten feet of the lower termination of the casing to the established ground surface or base of the pitless adapter or unit. Casing may be driven according to part 4725.3050, subpart 5.

Subp. 5.

Sampling faucet required.

A sampling faucet must be installed for each new public water-supply well. The faucet must be:

A.

metal;

B.

installed a minimum of 12 inches above the established ground surface or floor; and

C.

installed before any treatment devices and between the well and water storage.

Subp. 6.

Conversion to a public water-supply well.

A well, previously not used as a public water-supply well, may be used as a noncommunity or community public water-supply well only if the well meets the standards of this chapter. Plans and specifications must be submitted to, and approved by, the commissioner prior to use as a public water-supply well. This provision is not meant to be used for the construction of a "test" well or environmental bore hole converted to a public water-supply well in order to circumvent the notification, inspection, and plan approval requirements of this chapter.

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