Wisconsin Legislature: 002 - CR 15-085 Rule Text

Written comments may also be submitted to the Department using the Wisconsin Administrative Rules Internet Web site at http://adminrules.wisconsin.gov.

Hearing dates and the comment submission deadline are to be determined.

Section 1 NR 106.03 (1) is renumbered NR 106.03 (1r).

NR 106.03 (1r) "Bioaccumulative chemical of concern" or "BCC" means any substance that has the potential to cause adverse effects which, upon entering the surface waters, accumulates in aquatic organisms by a human health or wildlife bioaccumulation factor greater than 1000.

Section 2 NR 106.03 (1g) is created to read:

NR 106.03 (1g) "AMZ" means acute mixing zone concentration based on presence of a zone of initial dilution pursuant to NR 106.06 (3) (c).

Section 3 NR 106.03 (2m) is created to read:

NR 106.03 (2m) "Deficiency toxicity" means a condition where adverse effects occur to aquatic organisms because concentrations of common ions (e.g., sodium, calcium, magnesium, potassium, etc.) are too low.

Section 4 NR 106.03 (2m) note is created to read:

NR 106.03 (2m) note Changes in the concentration of ions in surrounding waters can cause organisms to expend too much energy trying to regulate the balance of water and dissolved materials in bodily fluids, and may result in death.

Section 5 NR 106.03 (5m) is created to read:

NR 106.03 (5m) "IC50" means the point estimate of the concentration of a toxic substance, wastewater effluent or other aqueous mixture that would cause a 50% reduction in a nonlethal biological measurement, such as reproduction or growth, of the exposed test organisms in a given time period.

Section 6 NR 106.03 (10) and (11) are repealed.

Section 7 NR 106.03 (13) is amended to read:

NR 106.03 (13) "TUa" or "toxic unit acute" means a value that is equal to 100 divided by the LC50 except as provided in s. NR 106.08(6)(d).

Section 8 NR 106.03 (13m) is created to read:

NR 106.03 (13m) "TUc" or "toxic unit chronic" means a value that is equal to 100 divided by the IC25 or the IC50 except as provided in s. NR 106.08(6)(d).

Section 9 NR 106.03 (14) is amended to read:

NR 106.03 (14) "Whole effluent toxicity" or "WET" means the aggregate toxic effect of an effluent as measured directly by a toxicity test.

Section 10 NR 106.04 (3m) is created to read:

NR 106.04 (3m) Water quality based effluent limitations may be imposed on internal waste streams before mixing with other waste streams or cooling water streams in lieu of imposing limitations at the point of discharge when imposition of limitations at the point source discharge location is impracticable or infeasible. Monitoring requirements as specified in s. NR 106.07(1) shall also be applied to the internal waste streams in these instances.

Section 11 NR 106.05 (1) (c) is amended:

NR 106.05 (1) (c) If the department determines that a limitation based on an aquatic life acute or chronic secondary value should be established in a permit according to the provisions in this section, a permittee may request an alternative wet WET limit in accordance with s. NR 106.07 (7).

Section 12 NR 106.05 (8) is repealed and recreated to read:

NR 106.05 (8) If representative discharge data are not available for a substance, water quality based effluent limitations may be included in a permit if, in the judgment of the department, water quality standards will be exceeded if the discharge of the substance is not limited.

Section 13 NR 106.05 (8) note is repealed.

Section 14 NR 106.06 (3) (b) is repealed and recreated to read:

NR 106.06 (3) (b) (intro) To assure compliance with par. (a), the department shall calculate the water quality based effluent limitation for a substance using the following procedures whenever the background concentration of the substance in the receiving water is less than the acute water quality criterion or secondary value:

1. A limitation shall be calculated using the following conservation of mass equation whenever sufficient site-specific data exist:

Limitation =(WQC) (Qs +(1−f)Qe) − (Qs − fQe) (Cs)

Where:

Limitation = Calculated limitation based on the acute toxicity criterion or secondary acute value (in units of mass per unit of volume).

WQC = The acute toxicity criterion appropriate for the receiving water as specified in chs. NR 102 to 105 or the secondary acute value determined according to ch. NR 105 or as referenced in sub. (1)

Qs = Receiving water design flow (in units of volume per unit time) pursuant to sub. (bm)

Qe = Effluent flow (in units of volume per unit time) as specified in s. NR 106.06(4)(d)

f = Fraction of the effluent flow that is withdrawn from the receiving water, and

Cs = Background concentration of the substance (in units of mass per unit volume) as specified in s. NR 106.06(4)(e).

[NOTE to LRB: this is the same equation found in NR 106.06 (4) (b) (1) and formatted the same.]

2. A limitation shall be calculated equal to the final acute value or secondary value as determined in s. NR 105.05 for the respective fish and aquatic life subcategory for which the receiving water is classified.

3. The department shall use the more restrictive calculated effluent limitation derived in subds. 1. and 2., as the water quality based effluent limitation. If the background concentration of the substance in the receiving water is greater than the acute water quality criterion or secondary value for the substance, then the procedure in sub. (6) shall be used to calculate the limitation.

Section 15 NR 106.06 (3) (bm) is created to read:

NR 106.06 (3) (bm) The value of Qs of the receiving water for calculating effluent limitations in par. (a) based upon the acute fish and aquatic life criteria or secondary values developed according to ch.NR 105 shall be determined on a case-by-case basis. In no case may the Qs exceed the average minimum 1-day flow which occurs once in 10 years (1-day Q10) or if the 1-day Q10 flow data is not available, 80% of the average minimum 7-day flow which occurs once in 10 years (7-day Q10).

Section 16 NR 106.06 (3) (c) (intro), 4., and 5. are amended to read:

NR 106.06 (3) (c) (intro) Except as provided in par. (d) sub. (2), water quality based effluent limitations as derived in par. (b) may exceed the final acute value or the secondary acute value within a zone of initial dilution provided that the acute toxicity criteria or secondary acute values are met within a short distance from the point of discharge. A zone of initial dilution shall only be approved if the discharger demonstrates to the department that mixing of the effluent with the receiving water in the zone of initial dilution is rapid and all the following conditions are met:

4. The acute toxicity criteria or secondary acute values must shall be met within 10% of the distance from the edge of the outfall structure to the edge of a mixing zone which may be determined in accordance with s. NR 102.05 (3).

5. The acute toxicity criteria or secondary acute values shall be met within a distance of 50 times the discharge length scale in any direction. The discharge length scale is defined as the square root of the cross-sectional area of any discharge outlet. If a multiport diffuser is used, this requirement must shall be met for each port using the appropriate discharge length scale for that port.

Section 17 NR 106.06 (3) (e) is created to read:

NR 106.06 (3) (e) The department shall use the methodology in ss. NR 106.07 (3) to (5) to express water quality based effluent limitations derived in this subsection as permit effluent limitations.

Section 18 NR 106.06 (4) (f) is created to read:

NR 106.06 (4) (f) The department shall use the methodology in ss. NR 106.07 (3) to (5) to express water quality based effluent limitations derived in this subsection as permit effluent limitations.

Section 19 NR 106.06 (7) is amended to read:

NR 106.06 (7) Effluent limitations may be established in a permit under this subsection based upon the acute and chronic aquatic life toxicity criteria expressed as dissolved concentrations which are determined using the procedures specified in ss. NR 105.05 (5) and 105.06 (8). Effluent limitations for metals calculated in this section shall be expressed as total recoverable in a permit.

Section 20 NR 106.07 (1) (title) is created to read:

NR 106.07 (1) (title) Permit monitoring frequency.

Section 21 NR 106.07 (2) is repealed and recreated to read:

NR 106.07 (2) General. Except as provided in subs. (3) and (4), a chemical specific water quality based effluent limitation that is calculated under this chapter shall be expressed in the permit as both a concentration limitation and a mass limitation unless the pollutant cannot appropriately be expressed by mass or a mass limitation is infeasible because the mass of the pollutant cannot be related to a measure of operation. Water quality based mass limits for discharges of chlorine are not required in permits. The concentration limitation shall be expressed in units of mg/L or equivalent units. The mass limitation shall be expressed in units of kg/day or equivalent units. All of the following procedures shall be used when calculating mass limitations:

(a) For dischargers subject to ch. NR 210, an acute toxicity based concentration limitation that is derived by the procedure in s. NR 106.06 shall be converted to a mass limitation by using the discharger's maximum effluent flow, expressed as a daily total flow, that is anticipated to occur for 24 continuous hours during the design life of the treatment facility.

(b) For all other dischargers not subject to ch. NR 210, an acute toxicity based concentration limitation that is derived by the procedures in s. NR 106.06 shall be converted to a mass limitation by using the discharger's maximum effluent flow, expressed as a daily total flow, that has occurred for 24 continuous hours and represents normal operations. When calculating a mass limitation, the department may consider a projected increase in effluent flow that will occur when production is increased or modified, or another wastewater source, including stormwater, that is added to an existing wastewater treatment facility. This paragraph does not waive the requirements of ch. NR 207.

(c) An aquatic life chronic, human health or wildlife-based concentration limitation that is determined by the procedures in s. NR 106.06 shall be converted to a mass limitation by using the same effluent flow rate that was used in s. NR 106(4)(d) to calculate the chronic toxicity concentration limitation.

(d) A chronic toxicity based mass limitation that is determined by the procedures in s. NR 106.11 shall be converted to a concentration limitation by using an effluent flow rate from s. NR 106.06(4)(d).

Section 22 NR 106.07 (2) note is created to read:

NR 106.07 (2) Note: An example of where a mass limitation is infeasible is water quality based mass limits for discharges of temperature. Therefore, temperature mass limitations are not required in permits.

Section 23 NR 106.07 (3) is repealed and recreated to read:

NR 106.07 (3) Expression of concentration limitations in permits for continuous discharges subject to NR 210. (a) Applicability. The procedures for expressing limitations in permits in this subsection apply to continuous discharges subject to ch. NR 210 where there is reasonable potential under s. NR 106.05 to exceed a water quality based effluent limitation based on fish and aquatic life protection, human health or wildlife protection that is calculated pursuant to s. NR 106.06. This subsection does not apply if another provision in this chapter or another administrative code requires a different time period for expressing limits for a specific pollutant, type of discharge or parameter, or if the department determines that expression of limitations in accordance with this subsection is impracticable pursuant to sub. (10).

Note: An example of a different time period for expressing limits for a specific pollutant or parameter is WET limitations as specified in s. NR 106.09.

(b) Expression of Water Quality Based Effluent Limitations based on Acute Criterion. If there is reasonable potential pursuant to s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on an acute criterion or secondary value, that limitation shall be expressed as a daily maximum and included in the WPDES permit.

(c) Expression of Water Quality Based Effluent Limitations based on Chronic Criterion. If there is reasonable potential pursuant to s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on a chronic criterion or secondary value that limitation shall be expressed as a weekly average and included in the WPDES permit.

(d) Expression of Water Quality Based Effluent Limitations based on Human Health or Wildlife Criterion. If there is reasonable potential under s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on a human health or wildlife criterion or secondary value, that limitation shall be expressed as a monthly average and included in the WPDES permit.

(e) Additional Permit Limitations. Both a weekly average and monthly average permit limitation shall be included in a WPDES permit for a pollutant whenever any water quality based effluent limitation for that pollutant is determined necessary pursuant to s. NR 106.05. A daily maximum limitation shall be included in a WPDES permit in addition to the weekly average and monthly average limitation if the daily maximum limitation is determined necessary pursuant to par. (b). The department shall use all of the following procedures to include weekly average and monthly average limitations in WPDES permits:

1. If a daily maximum limitation is the only limitation determined necessary for a pollutant pursuant to s. NR 106.05, a weekly average and monthly average limitation shall still be included in the permit and shall be set equal to the daily maximum limitation or the calculated weekly average and monthly average water quality based effluent limitations, whichever is more restrictive.

2. If a weekly average limitation is determined necessary for a pollutant pursuant to s. NR 106.05, but a monthly average limitation is not determined necessary for that pollutant in the permit pursuant to s. NR 106.05, a monthly average limitation shall still be included in the permit and shall be set equal to the weekly average limitation or the monthly average water quality based effluent limitation calculated under s. NR 106.06, whichever is more restrictive. A daily maximum limitation shall be included if deemed necessary pursuant to s. NR 106.05.

3. If a daily maximum and monthly average limitation are determined necessary in a permit for a pollutant pursuant to s. NR 106.05, but a weekly average limit is not necessary for that pollutant pursuant to s. NR 106.05, a weekly average limitation shall still be included in the permit for the pollutant and shall be set equal to the daily maximum limitation or the weekly average water quality based effluent limitation calculated under s. NR 106.06, whichever is more restrictive.

4. If a monthly average limitation is the only limitation determined to be necessary for a pollutant pursuant to s. NR 106.05, a weekly average limitation shall still be included in the permit and shall be set equal to the weekly average water quality based effluent limitation calculated under s. NR 106.06, or a weekly average limitation calculated using the following procedure, whichever is more restrictive:

Weekly Average Limitation = (Monthly Average Limitation*MF)

Where:

MF= Multiplication factor as defined in Table 1

CV= The coefficient of variation (CV) as calculated in s. NR 106.07(5m)

n= the number of samples per month required by WPDES permit

NR 106.07 (3) (e) (4) Table 1- Multiplication Factor

n=1

n=2

n=3

n=4

n=8

n=12

n=16

n=20

n=24

n=30

0.1

1.07

1.13

1.14

1.16

1.18

1.20

1.21

1.22

0.2

1.14

1.25

1.29

1.33

1.39

1.42

1.43

1.45

1.46

0.3

1.22

1.37

1.45

1.50

1.60

1.65

1.68

1.70

1.72

1.74

0.4

1.30

1.50

1.60

1.67

1.82

1.89

1.94

1.97

2.00

2.02

0.5

1.38

1.622

1.75

1.84

2.04

2.14

2.20

2.25

2.28

2.32

0.6

1.46

1.73

1.89

2.01

2.25

2.38

2.46

2.52

2.57

2.62

0.7

1.54

1.84

2.02

2.16

2.45

2.61

2.72

2.79

2.85

2.91

0.8

1.61

1.94

2.14

2.29

2.64

2.83

2.95

3.04

3.11

3.19

0.9

1.69

2.03

2.25

2.41

2.81

3.03

3.17

3.28

3.36

3.45

1.0

1.76

2.11

2.34

2.52

2.96

3.20

3.37

3.49

3.59

3.70

1.1

1.83

2.18

2.43

2.62

3.09

3.36

3.55

3.69

3.80

3.93

1.2

1.90

2.25

2.50

2.70

3.20

3.50

3.71

3.86

3.99

4.13

1.3

1.97

2.31

2.57

2.77

3.30

3.62

3.85

4.02

4.15

4.31

1.4

2.03

2.37

2.63

2.83

3.39

3.73

3.97

4.15

4.30

4.47

1.5

2.09

2.42

2.68

2.89

3.46

3.82

4.08

4.27

4.43

4.62

1.6

2.15

2.42

2.73

2.89

3.46

3.89

4.16

4.37

4.54

4.62

1.7

2.21

2.52

2.77

2.98

3.57

3.96

4.24

4.46

4.64

4.85

1.8

2.27

2.56

2.81

3.01

3.61

4.01

4.30

4.53

4.72

4.94

1.9

2.32

2.60

2.84

3.05

3.65

4.05

4.35

4.59

4.79

5.02

2.0

2.37

2.64

2.87

3.07

3.67

4.09

4.40

4.64

4.84

5.09