PURPOSE: This rule sets standards on the proper plugging of wells used in heat pump applications.

1. (1) Vertical Closed-Loop Heat Pump Wells. To plug a properly constructed vertical closed-loop heat pump well the following specifications must be met:

   1. (A) Remove all heat transfer fluid from the closed-loop and take necessary precautions to ensure groundwater protection;
   2. (B) Dig down to the top of borehole and cut off the loop pipe. This must be at least three feet (3') below the surface. Pump the remaining loop full of bentonite or cement slurry. Allow the grout to fill the upper one foot (1') of borehole. Fill remaining hole with compacted earth or pavement; and
   3. (C) Submit registration report form and fee to the division within sixty (60) days which documents the proper plugging of the heat pump well. Upon review and approval of the registration report form, a registration number will be sent to the landowner which designates that the well was plugged according to the minimum standards.
2. (2) Open-Loop Heat Pump Wells. Wells used to supply water for the heat pump and water return wells must be plugged as set out in 10 CSR 23-3.110 Plugging of Wells. A registration report form and fee must be submitted.

3. (3) Plugging Improperly Constructed Heat Pump Wells. When it is determined by the division that a heat pump well is constructed improperly, it must be brought into compliance with the rules or plugged. To plug an improperly constructed heat pump well, the following specifications must be met:

   1. (A) Remove all pipes from hole;
   2. (B) Clean out well bore of loose material;
   3. (C) Plug well full-length with approved grout; and
   4. (D) Submit registration report form and fee.

AUTHORITY: sections 256.606, 256.623, and 256.626, RSMo 2000.* Emergency rule filed Nov. 16, 1993, effective Dec. 11, 1993, expired April 9, 1994. Original rule filed Aug. 17, 1993, effective March 10, 1994. Amended: Filed May 17, 2013, effective Dec. 30, 2013. *Original authority: 256.606, RSMo 1991 and 256.623 and 256.626, RSMo 1985, amended 1991.