Except as provided in subpart 2, a connection to a casing of a water-supply well made less than 12 inches above the established ground surface must be made with a pitless adapter or pitless unit. The connection must not be submerged in water at the time of installation. Native materials must be packed tightly around the pitless adapter or pitless unit to the ground surface. The pitless adapter or pitless unit must:
be constructed to provide complete clearance within the internal diameter of the casing;
be designed to be field-welded by holding the welding rod in a vertical or horizontal position, or bench-welded before field installation with a material as corrosion-resistant as the parent material;
have all threaded joints watertight with no threads exposed;
impart no taste, odor, or toxic material to the water; and
connect to the casing by a threaded connection, welded connection, bolted flange with gasket, clamp and gasket, or compression gasket.
A welded, solvent welded, or threaded coupling, adapter, or swaged fitting meeting the material standards of part 4725.2350, 4725.2550, or 4725.6650 may be used to connect a casing to a pitless adapter or unit.
Additionally, a pitless unit using a compression seal must provide for the well casing to extend at least 2.5 inches into the throat of the pitless unit. The compression collar must be held in place with corrosion-resistant bolts, nuts, and washers. The installer of a clamp-on or weld-on pitless adapter must use a guide or template for cutting the hole in the casing to accommodate the pitless adapter.
A welded or threaded fitting meeting the requirements of part 4725.3150, subpart 2, may be connected to the side, cap, or cover of a water-supply well casing and be used for venting, remediation, measurement of water levels or testing, treatment, or for an electrical connection. A water discharge line must be connected with a pitless unit or pitless adapter.
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
September 2, 2008
Copyright © 2008 by the Revisor of Statutes, State of Minnesota. All rights reserved.