Chapter NR 106

NR 106.88 History History: Cr. Register, January, 2000, No. 529, eff. 2-1-00; CR 09-123: am. (3) Register July 2010 No. 655, eff. 8-1-10; CR 15-085: r. and recr. (1) to (3), r. (4), r. and recr. (5), r. (6) Register August 2016 No. 728, eff. 9-1-16.

NR 106.89 NR 106.89 Alternative whole effluent toxicity monitoring and limitations for dischargers of chloride.

NR 106.89(1) (1) General. In addition to interim, target, and calculated water quality-based effluent limitations and target values for chloride, the department may establish whole effluent toxicity testing requirements and limitations under ss. NR 106.08 and 106.09.

NR 106.89(2) (2) Findings. The department finds all of the following:

NR 106.89(2)(a) (a) Acute whole effluent toxicity limitations cannot be attained if the effluent concentration of chloride exceeds 2,500 mg/L.

NR 106.89(2)(b) (b) Chronic whole effluent toxicity limitations cannot be attained if the effluent concentration of chloride exceeds 2 times the calculated chronic water quality-based effluent limitation.

NR 106.89(2)(c) (c) If chloride is the sole source of acute or chronic whole effluent toxicity it is appropriate that chloride limitations be used instead of WET limitations to attain and maintain narrative criteria in s. NR 102.04 (1) (d) and (4) (d).

NR 106.89(3) (3) Chloride limits in lieu of acute wet limits. Chloride limitations shall be included in the permit in lieu of acute whole effluent toxicity testing requirements and acute whole effluent toxicity limitations until source reduction actions are completed if any of the following apply:

NR 106.89(3)(a) (a) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride exceeds 2,500 mg/L.

NR 106.89(3)(b) (b) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride is less than 2,500 mg/L, but in excess of the calculated acute water quality-based effluent limitation, and additional data are submitted that demonstrate that chloride is the sole source of acute toxicity.

NR 106.89(4) (4) Chloride limits in lieu of chronic wet limits. Chloride limitations shall be included in the permit in lieu of chronic whole effluent toxicity testing requirements and chronic whole effluent toxicity limitations until source reduction actions are completed if either of the following applies:

NR 106.89(4)(a) (a) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride exceeds 2 times the calculated chronic water quality-based effluent limitation.

NR 106.89(4)(b) (b) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride is less than 2 times the calculated chronic water quality-based effluent limitation, but in excess of the calculated chronic water quality-based effluent limitation, and additional data are submitted which demonstrate that chloride is the sole source of chronic toxicity.

NR 106.89(5) (5) Decision documentation. The department shall specify the decision to include chloride limitations instead of whole effluent toxicity limitations in the permit fact sheet.

NR 106.89(6) (6) Reevaluation. The department shall reevaluate the need for whole effluent toxicity and chloride monitoring or limitations upon permit reissuance.

NR 106.89 History History: Cr. Register, January, 2000, No. 529, eff. 2-1-00; CR 15-085: r. and recr. Register August 2016 No. 728, eff. 9-1-16; correction in (2) (c) made under s. 35.17, Stats., Register August 2016 No. 728.

NR 106.90 NR 106.90 Source reduction.

NR 106.90(1) (1) Introduction. A 3-tiered system of source reduction measures is established in ascending order of increasing capital and operating costs.

NR 106.90(2) (2) Tier 1 source reduction measures are those voluntary source reduction activities that identify and quantify chloride and softened water sources and usage, educate users and system operators on the need to minimize salt and softened water demands and promote better housekeeping practices that will reduce chloride and softened water consumption, and other activities similar in nature. Tier 1 source reduction measures may include any of the following:

NR 106.90(2)(a) (a) For POTWs:

NR 106.90(2)(a)1. 1. Identify sources of chloride to the sewer system.

NR 106.90(2)(a)2. 2. Educate homeowners on the impact of chloride from residential softeners, discuss options available for increasing softener salt efficiency, and request voluntary reductions.

NR 106.90(2)(a)3. 3. Recommend residential softener tune-ups on a voluntary basis.

NR 106.90(2)(a)4. 4. Request voluntary support from local water softening businesses in the efforts described in subds. 2. and 3.

NR 106.90(2)(a)5. 5. Educate licensed installers and self-installers of softeners on providing optional hard water for outside faucets for residences.

NR 106.90(2)(a)6. 6. Request voluntary reductions in chloride input from industrial and commercial contributors.

NR 106.90(2)(a)7. 7. Where a public water utility has been identified as a significant contributor of chloride to the sewer system, request that the water utility conduct activities listed in par. (b).

NR 106.90(2)(b) (b) For direct-discharging municipal or commercial water softening plants:

NR 106.90(2)(b)1. 1. Identify the users of soft water or the processes using soft water, and the amounts they use.

NR 106.90(2)(b)2. 2. Determine which users or processes can tolerate unsoftened water, and determine their impact on demand.

NR 106.90(2)(b)3. 3. Determine which users can close-loop their once-through cooling system or which processes can be close-looped, and determine their impact on demand.

NR 106.90(2)(b)4. 4. Seek voluntary demand reductions.

NR 106.90(2)(c) (c) For dairies, train plant personnel to be more aware of salt conservation, emphasizing simple, cost effective housekeeping measures. For example, spilled salt can be cleaned up as a solid waste rather than flushed down the floor drain.

NR 106.90(2)(d) (d) For those facilities which process vegetables or meats:

NR 106.90(2)(d)1. 1. Train personnel as described in par. (c) in housekeeping measures.

NR 106.90(2)(d)2. 2. Optimize softener operation to ensure the appropriate regeneration interval and salt dosage are used.

NR 106.90(2)(e) (e) For any other facility not listed in pars. (a) to (d), conduct activities that identify and quantify chloride and softened water sources and usage and educate personnel on appropriate housekeeping practices and the need to minimize salt and softened water demands.

NR 106.90(3) (3) Tier 2 source reduction measures are those voluntary source reduction activities that improve and optimize equipment and processes, encourage restricted chloride use by users, eliminate wasteful practices and establish recycling practices where feasible, and other activities similar in nature. Tier 2 source reduction measures may include any of the following:

NR 106.90(3)(a) (a) For POTWs, institute sewer use ordinances that:

NR 106.90(3)(a)1. 1. Require significant industrial and commercial contributors to evaluate their water treatment systems with regard to softened water requirements, with the results of that evaluation being the basis for potential restrictions of chloride inputs.

NR 106.90(3)(a)2. 2. Mandate a DIR and high salt efficiency standard for new residential softeners.

NR 106.90(3)(a)3. 3. Mandate participation in a residential softener tune-up program, which involves qualified periodic servicing to ensure proper control settings and adjustments.

NR 106.90(3)(a)4. 4. Where a public water utility has been identified as a significant contributor of chloride to the sewer system, request that the water utility conduct activities listed in par. (b).

NR 106.90(3)(b) (b) For direct-discharging municipal or commercial water softening plants:

NR 106.90(3)(b)1. 1. Optimize softener operation to ensure the appropriate regeneration interval and salt dosage are used.

NR 106.90(3)(b)2. 2. If the regeneration is manual or timer-initiated, switch to a DIR controller.

NR 106.90(3)(b)3. 3. Evaluate the feasibility of brine reclamation.

NR 106.90(3)(c) (c) For dairies:

NR 106.90(3)(c)1. 1. Improve the handling of salt brines and the handling of cheese into and out of brine systems. Consider capital improvements such as automating the brine system, properly designed drip pans and splash guards.

NR 106.90(3)(c)2. 2. Optimize softener operation to ensure the appropriate regeneration interval and salt dosage are used.

NR 106.90(3)(c)3. 3. If the regeneration is manual or timer-initiated, evaluate the feasibility of switching to a DIR controller.

NR 106.90(3)(c)4. 4. Evaluate the feasibility of softener brine reclamation.

NR 106.90(3)(c)5. 5. Determine which subprocesses can tolerate unsoftened water, and make appropriate changes.

NR 106.90(3)(c)6. 6. Determine whether once-through cooling systems can be close-looped, and make appropriate changes.

NR 106.90(3)(c)7. 7. For plants that condense whey, evaluate the feasibility of using condensate of whey (COW) water for the first rinse for clean-in-place (CIP) systems and for boiler makeup water.

NR 106.90(3)(d) (d) For those facilities which process vegetables:

NR 106.90(3)(d)1. 1. If the regeneration is manual or timer-initiated, evaluate the feasibility of switching to a DIR controller.

NR 106.90(3)(d)2. 2. Evaluate the feasibility of softener brine reclamation.

NR 106.90(3)(d)3. 3. Investigate the feasibility of using a phosphonate additive instead of softening the cooling water.

NR 106.90(3)(d)4. 4. Evaluate the feasibility of reusing once-through cooling water as boiler make-up.

NR 106.90(3)(d)5. 5. Investigate the feasibility of using unsoftened water for container fill.

NR 106.90(3)(e) (e) For those facilities which process meats:

NR 106.90(3)(e)1. 1. If the regeneration is manual or timer-initiated, evaluate the feasibility of switching to a DIR controller.

NR 106.90(3)(e)2. 2. Evaluate the feasibility of softener brine reclamation.

NR 106.90(3)(f) (f) For any other facility not listed in pars. (a) to (e), conduct activities that improve and optimize equipment and processes, eliminate wasteful practices and establish recycling practices to achieve chloride reductions.

NR 106.90(4) (4) Tier 3 source reduction measures are those voluntary source reduction activities that evaluate the feasibility of replacing or upgrading equipment and processes or evaluate the feasibility of using alternative technologies or processes, and other activities similar in nature. Tier 3 source reduction measures may include any of the following:

NR 106.90(4)(a) (a) For POTWs, where residential point-of-use softening is the primary chloride input:

NR 106.90(4)(a)1. 1. Evaluate the requirement for new and replacement softeners to be metered demand type, with a higher, greater than 3350 grains of hardness exchange per pound of salt, efficiency capability.

NR 106.90(4)(a)2. 2. Evaluate the imposition of installation restrictions so that outside hose bibs are on unsoftened water. If restrictions are imposed, new homes and those in real estate transfers should be required to have plumbing restrictions for hard water by-passes, and the requirement should apply to self-installed equipment as well.

NR 106.90(4)(b) (b) For POTWs, where a central water supply softener is the primary chloride input, conduct activities listed in par. (c).

NR 106.90(4)(c) (c) For direct-discharging municipal or commercial water softening plants:

NR 106.90(4)(c)1. 1. Evaluate the feasibility of achieving greater salt efficiencies, greater than 3350 grains of hardness exchange per pound of salt.

NR 106.90(4)(c)2. 2. Evaluate softening alternatives that replace the sodium cycle ion exchange method of softening.

NR 106.90(4)(c)3. 3. Blend softened and unsoftened water to strike a balance between delivered water quality and environmental protection.

NR 106.90(4)(d) (d) For dairies:

NR 106.90(4)(d)1. 1. For plants that make brine salted cheeses, evaluate the feasibility of membrane filtration for reconditioning the brine so that it can be reused.

NR 106.90(4)(d)2. 2. For plants that make brine salted cheeses, evaluate the feasibility of using a no-brine make procedure in which salt is added directly to curd during the manufacturing procedure, thereby reducing salt discharges from spent brines.

NR 106.90(4)(e) (e) For those facilities which process vegetables:

NR 106.90(4)(e)1. 1. Evaluate the feasibility of eliminating brine flotation for quality grading, if applicable.

NR 106.90(4)(e)2. 2. Evaluate the feasibility of installing a closed-loop system for cooling water.

NR 106.90(4)(e)3. 3. Evaluate the feasibility of installing a brine recovery and reuse system for reducing salt waste at the point of supplying flavorings to containers.

NR 106.90(4)(f) (f) For those facilities which process meats:

NR 106.90(4)(f)1. 1. Investigate the feasibility of replacing brine chills with air, water or air-water chills.

NR 106.90(4)(f)2. 2. Reduce drainback through operational and equipment improvements.

NR 106.90(4)(f)3. 3. Investigate the feasibility of chill brine reconditioning and reuse.

NR 106.90(4)(f)4. 4. Evaluate the feasibility of reusing once-through cooling water, or installing a closed-loop cooling water system.

NR 106.90(4)(f)5. 5. Evaluate phosphonate additives instead of softened water.

NR 106.90(4)(g) (g) For any other facility not listed in pars. (a) to (f), evaluate the feasibility of replacing or upgrading equipment and processes, and the use of alternative softening technologies to affect chloride reductions.

NR 106.90(5) (5) Source reduction reporting. Following the completion of tier 1, 2 or 3 source reduction activities specified in the permit, but no later than 6 months prior to permit expiration, the permittee shall file a written report to the department documenting the current reduction as well as the anticipated future reduction in salt usage and chloride effluent concentrations.