NR 809.905(1)(b)(b) The department identifies the best available technology, treatment techniques or other means available for achieving compliance with the maximum contaminant levels for the radionuclides listed in ss. NR 809.50 (1) and 809.51 for the purposes of issuing conditional waivers to small drinking water systems, defined as those serving 10,000 persons or fewer, as shown in s. NR 809.50 (4), Tables K and L.

NR 809.905(2)(2) Treatment as a condition of uranium waivers. The department shall require community water systems to install or use, or both install and use, any treatment technology identified in s. NR 809.50 (3), Table B, or in the case of community water systems that serve 10,000 persons or fewer, s. NR 809.50 (3), Table C and Table E, as a condition for granting a conditional waiver except as provided in sub. (3).

NR 809.905(3)(3) Waiver for alternative treatment if BATs are not effective. If a water supplier for a community water system can demonstrate through comprehensive engineering assessments, which may include pilot plant studies, that the treatment technologies identified in this section would only achieve a de minimus reduction in the contaminant level, the department may issue a schedule for compliance that requires the community water system being granted the conditional waiver to examine other treatment technologies as a condition of obtaining the conditional waiver.

NR 809.905(4)(4) Requirement to install alternative treatment. If the department determines that a treatment technology identified under sub. (3) is technically feasible, the department may require the public water system to install or use, or both install and use, that treatment technology in connection with a compliance schedule issued under s. NR 809.90. The department’s determination shall be based upon studies by the water supplier for the public water system and other relevant information.

NR 809.905(5)(5) Bottled water, point of entry, point of use or other means as a condition of granting a waiver. The department may require a community water system to use bottled water, point-of-use devices, point-of-entry devices or other means as a condition of granting a conditional waiver from the requirements of s. NR 809.50 or 809.51 to avoid an unreasonable risk to health.

NR 809.905(6)(6) Requirements for bottled water use. Community water systems that use bottled water as a condition for receiving a conditional waiver from s. NR 809.50 or 809.51 shall meet the requirements in either s. NR 809.90 (4) (a) or (b) and (c).

NR 809.905(7)(7) Conditions for using point of use or point of entry devices. Community water systems that use point-of-use or point-of-entry devices as a condition for obtaining a conditional waiver from the uranium MCL shall meet the conditions in ss. NR 809.50 (4) (b) and 809.90 (3).

NR 809.91(1)(1) Variances for non-community water systems. A non-community water system is eligible for a variance from the nitrate as nitrogen maximum contaminant level if all of the following are met:

NR 809.91(1)(a)(a) The department determines that because of the characteristics of the raw water sources which are reasonably available, the non-community water system cannot comply with the maximum contaminant level for nitrate as nitrogen.

NR 809.91(1)(c)(c) The water supplier continuously posts a department approved notice at all water taps supplied with water by the non-community water system. The notice shall state that the nitrate as nitrogen level exceeds 10 mg/l and describe the potential health effects of exposure.

NR 809.91(1)(d)(d) The water supplier ensures that water from their public water system will not be available to children under 6 months of age and provides bottled water which complies with all maximum contaminant levels for such children.

NR 809.91(2)(2) Variances for community water systems. A community water system serving a nursing home, prison or mental health care facility, is eligible for a variance from the nitrate as nitrogen maximum contaminant level if all of the following are met:

NR 809.91(2)(c)(c) The water supplier for the institution continuously posts a department approved notice at all water taps supplied with water by the community water system. The notice shall state that the nitrate as nitrogen level exceeds 10 mg/l and describe the potential health effects of exposure.

NR 809.91(2)(d)(d) The water supplier for the institution ensures that water from its public water system will not be available to children under 6 months of age and provides bottled water which complies with all maximum contaminant levels for such children.

NR 809.91(3)(3) Control measures for variances. The department may condition the issuance of a variance under this section on compliance with such control measures as it deems necessary. Failure to comply with any term or condition of a variance granted by the department under this section voids the variance.

NR 809.950(1)(1) General requirements. All water suppliers for public water systems shall comply with the requirements in this subchapter.

NR 809.950(2)(2) Who shall give public notice. Each water supplier for a public water system including, community water systems, non-transient non-community water systems, and transient non-community water systems, shall give notice for all violations of national primary drinking water regulations (NPDWR) and for other situations, as listed in sub. (3). The term “NPDWR violations” is used in this subchapter to include violations of the maximum contaminant level, maximum residual disinfection level, treatment technique, monitoring requirements, and testing procedures in this chapter. Appendix A to this subchapter identifies the tier assignment for each specific violation or situation requiring a public notice.