PURPOSE: This rule prevents the use of monitoring wells for any purpose other than the purpose for which they were designed and allows certain modifications to the application of these rules.

1. (1) Monitoring wells shall not be converted to any other type of well unless approved in advance by the division.
2. (2) When strict application of these rules presents practical difficulties or unusual hardships, the division, on a case-by-case basis, may modify the application of these rules consistent with the general purpose and intent of these rules and the law. The division may then impose certain conditions as are necessary, in the opinion of the division, to protect the groundwater of the state and health, safety, and general well-being of persons using, or potential users, of the groundwater (see 10 CSR 23-1.040 Modification by the Division for procedures concerning variances).
3. (3) It is the obligation and responsibility of the monitoring well installation contractor to ensure that the monitoring well is constructed according to these rules and that the annular space, if one exists, is sealed. The monitoring well must be properly plugged or repaired when the annular space is no longer sealed or the well is no longer performing its intended function.
4. (4) When drilling water is needed, it must be of potable quality.

AUTHORITY: sections 256.606 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 Nov. 1, 1995, effective June 30, 1996. Amended: Filed Nov. 18, 2010, effective July 30, 2011. *Original authority: 256.606, RSMo 1991 and 256.626, RSMo 1985, amended 1991.