A groundwater system that does not detect a contaminant specified in 40 C.F.R. § 141.62 (July 1, 2018) in its initial monitoring as specified by 40 C.F.R. § 141.24(f)(4) (July 1, 2018) may apply to the department for a waiver from the annual and triennial monitoring. A surface water system that does not detect a contaminant specified in 40 C.F.R. § 141.62 (July 1, 2018) in its initial monitoring as specified by 40 C.F.R. § 141.24(f)(4) (July 1, 2018) may apply to the department for a waiver from annual monitoring. Conditions for the granting of a waiver are as follows:

1. (1) The waiver for groundwater systems expires at the end of the second compliance period after it is granted. The waiver for surface water systems expires at the end of the current compliance period. A groundwater system must reapply for a waiver after the expiration of the previous waiver. A surface water system must be reevaluated by the department after the expiration of the previous waiver;
2. (2) A groundwater system must monitor once at each entry point and update its vulnerability assessment considering the factors specified in subdivision (4) of this section while the waiver is in effect. Based on the vulnerability assessment, the department must determine whether to reconfirm that the system is not vulnerable to VOC contamination. If the department does not make this reconfirmation within three years after the initial determination, the waiver is invalidated and the system is required to sample annually as specified in 40 C.F.R. § 141.24(f)(5) (July 1, 2018);
3. (3) A surface water system must monitor once at each entry point while the waiver is in effect;

4. (4) The department may grant a waiver after evaluating the following:

   1. (a) Previous analytical results;
   2. (b) The proximity of the system to a potential point or nonpoint source of contamination;
   3. (c) The environmental persistence and transport of the contaminant;
   4. (d) The protection of a groundwater source against contamination due to such factors as depth of well, soil type, and integrity of well casing. Surface water systems must consider watershed protection; and

   5. (e) The number of persons served by the water system and proximity of a smaller system to a larger system.

      A groundwater system must submit written evidence that it complies with the criteria in subdivision (4) of this section and a completed waiver application to the department. If any of the information required by subdivision (4) of this section is unknown or indicates that contamination is likely to occur, the department may not grant the waiver.

      The decision by the department to grant a waiver must be in writing and must establish the basis for the waiver determination. The determination may be initiated by the department or upon application by a public water system.

      The public water system must specify the basis for its waiver request. The department shall review and may revise its determination of the appropriate monitoring frequency if the system submits new monitoring data or if other data relevant to the system's appropriate monitoring frequency become available.

Source: 31 SDR 21, effective August 24, 2004; 36 SDR 111, effective January 11, 2010 ; 45 SDR 159, effective July 1, 2019 .

General Authority: SDCL 34A-3A-3.

Law Implemented: SDCL 34A-3A-3(2).

Prior versions effective: 2010-01-11.