74:04:01:03.  Required minimum fluoride levels. If the fluoride ion content of the water from any entry point for a public water supply is less than 0.5 mg/l, equipment must be provided and operated to adjust the fluoride ion concentration in the range of 0.5 mg/l to 0.9 mg/l, with an optimum level of 0.7 mg/l. Upon request and submission of laboratory sample results by the system, the department may grant a fluoridation exemption for an entry point when the natural fluoride ion concentration is greater than or equal to 0.5 mg/l. An exemption will be based on annual laboratory sample results of the natural fluoride ion concentration at each entry point. If a system's annual entry point sample has a natural fluoride ion concentration less than 0.5 mg/l, the system will be required to submit a confirmation sample and the average of the two samples will be used to determine exemption status. Based on sampling data and operational history, the department may grant, deny, or revoke an exemption.

          Source: SL 1975, ch 16, § 1; transferred from § 34:07:01:03. effective July 1, 1979; 13 SDR 129, 13 SDR 141, effective July 1, 1987; 42 SDR 97, effective January 4, 2016.

          General Authority: SDCL 34-24A-2.

          Law Implemented: SDCL 34-24A-1, 34-24A-2, 34-24A-3.