Wisconsin Administrative Code
Department of Natural Resources
NR 200-299 - Environmental Protection Wisconsin Pollutant Discharge Elimination System
Chapter NR 256 - Metal molding and casting
Subchapter I - Aluminum Casting Subcategory
Section NR 256.12 - Effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available
Current through August 26, 2024
Except as provided in 40 CFR 125.30 to 125.32, any existing point source subject to this subchapter, including noncontinuous direct dischargers, shall achieve the following BPT effluent limitations. Grinding scrubber operations may not discharge process wastewater pollutants to waters of the state.
TABLE 1
ALUMINUM CASTING SUBCATEGORY
CASTING CLEANING OPERATIONS
BPT Effluent Limitations |
|||||
Noncontinuous Direct Dischargers |
|||||
Maximum for any 1 day |
Maximum for monthly average |
Maximum for any 1 day |
Maximum for monthly average |
Annual average |
|
Pollutant or pollutant property |
kg/1,000 kkg (pounds per million pounds) of metal poured |
mg/l(1) |
mg/l(1) |
(2) |
|
Copper (T) |
0.0771 |
0.0421 |
0.77 |
0.42 |
0.017 |
Lead (T) |
0.0791 |
0.039 |
0.79 |
0.39 |
0.022 |
Zinc (T) |
0.114 |
0.0431 |
1.14 |
0.43 |
0.027 |
Oil & grease |
3.0 |
1.0 |
30 |
10 |
0.501 |
TSS |
3.8 |
1.5 |
38 |
15 |
1.0 |
pH |
(3) |
(3) |
(3) |
(3) |
(3) |
(1) These concentrations shall be multiplied by the ratio of (12/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2) kg/1,000 kkg (pounds per million pounds) of metal poured.
(3) Within the range of 7.0 to 10.0 to all times.
TABLE 2
ALUMINUM CASTING SUBCATEGORY
CASTING QUENCH OPERATIONS
BPT Effluent Limitations |
|||||
Noncontinuous Direct Dischargers |
|||||
Maximum for any 1 day |
Maximum for monthly average |
Maximum for any 1 day |
Maximum for monthly average |
Annual average |
|
Pollutant or pollutant property |
kg/1,000 kkg (pounds per million pounds) of metal poured |
mg/l(1) |
mg/l(1) |
(2) |
|
Copper (T) |
0.0093 |
0.0051 |
0.77 |
0.42 |
0.0021 |
Lead (T) |
0.0096 |
0.0047 |
0.79 |
0.39 |
0.0027 |
Zinc (T) |
0.0138 |
0.0052 |
1.14 |
0.43 |
0.0033 |
Oil & grease |
0.363 |
0.121 |
30 |
10 |
0.0605 |
TSS |
0.46 |
0.182 |
38 |
15 |
0.121 |
pH |
(3) |
(3) |
(3) |
(3) |
(3) |
(1) These concentrations shall be multiplied by the ratio of (1.45/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2) kg/1,000 kkg (pounds per million pounds) of metal poured.
(3) Within the range of 7.0 to 10.0 to all times.
TABLE 3
ALUMINUM CASTING SUBCATEGORY
DIE CASTING OPERATIONS
BPT Effluent Limitations |
|||||
Noncontinuous Direct Dischargers |
|||||
Maximum for any 1 day |
Maximum for monthly average |
Maximum for any 1 day |
Maximum for monthly average |
Annual average |
|
Pollutant or pollutant property |
kg/1,000 kkg (pounds per million pounds) of metal poured |
mg/l(1) |
mg/l(1) |
(2) |
|
Copper (T) |
0.0066 |
0.0036 |
0.77 |
0.42 |
0.0015 |
Lead (T) |
0.0068 |
0.0034 |
0.79 |
0.39 |
0.0019 |
Zinc (T) |
0.0098 |
0.0037 |
1.14 |
0.43 |
0.0023 |
Total phenols |
0.0074 |
0.0026 |
0.86 |
0.3 |
0.0017 |
Oil & grease |
0.259 |
0.0864 |
30 |
10 |
0.0432 |
TSS |
0.33 |
0.13 |
38 |
15 |
0.0864 |
pH |
(3) |
(3) |
(3) |
(3) |
(3) |
(1) These concentrations shall be multiplied by the ratio of (1.04/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2) kg/1,000 kkg (pounds per million pounds) of metal poured.
(3) Within the range of 7.0 to 10.0 to all times.
TABLE 4
ALUMINUM CASTING SUBCATEGORY
DUST COLLECTION SCRUBBER OPERATIONS
BPT Effluent Limitations |
|||||
Noncontinuous Direct Dischargers |
|||||
Maximum for any 1 day |
Maximum for monthly average |
Maximum for any 1 day |
Maximum for monthly average |
Annual average |
|
Pollutant or pollutant property |
kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed |
mg/l(1) |
mg/l(1) |
(2) |
|
Copper (T) |
0.231 |
0.126 |
0.77 |
0.42 |
0.0511 |
Lead (T) |
0.237 |
0.117 |
0.79 |
0.39 |
0.0661 |
Zinc (T) |
0.343 |
0.129 |
1.14 |
0.43 |
0.0811 |
Total phenols |
0.258 |
0.09 |
0.86 |
0.3 |
0.0601 |
Oil & grease |
9.01 |
3.0 |
30 |
10 |
1.5 |
TSS |
11.4 |
4.51 |
38 |
15 |
3.0 |
pH |
(3) |
(3) |
(3) |
(3) |
(3) |
(1) These concentrations shall be multiplied by the ratio of (0.036/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2) kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed.
(3) Within the range of 7.0 to 10.0 to all times.
TABLE 5
ALUMINUM CASTING SUBCATEGORY
INVESTMENT CASTING
BPT Effluent Limitations |
|||||
Noncontinuous Direct Dischargers |
|||||
Maximum for any 1 day |
Maximum for monthly average |
Maximum for any 1 day |
Maximum for monthly average |
Annual average |
|
Pollutant or pollutant property |
kg/1,000 kkg (pounds per million pounds) of metal poured |
mg/l(1) |
mg/l(1) |
(2) |
|
Copper (T) |
8.48 |
4.63 |
0.77 |
0.42 |
1.87 |
Lead (T) |
8.7 |
4.3 |
0.79 |
0.39 |
2.42 |
Zinc (T) |
12.6 |
4.74 |
1.14 |
0.43 |
2.97 |
Oil & grease |
330 |
110 |
30 |
10 |
55.1 |
TSS |
419 |
165 |
38 |
15 |
110 |
pH |
(3) |
(3) |
(3) |
(3) |
(3) |
(1) These concentrations shall be multiplied by the ratio of (1,320/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2) kg/1,000 kkg (pounds per million pounds) of metal poured.
(3) Within the range of 7.0 to 10.0 to all times.
TABLE 6
ALUMINUM CASTING SUBCATEGORY
MELTING FURNACE SCRUBBER OPERATIONS
BPT Effluent Limitations |
|||||
Noncontinuous Direct Dischargers |
|||||
Maximum for any 1 day |
Maximum for monthly average |
Maximum for any 1 day |
Maximum for monthly average |
Annual average |
|
Pollutant or pollutant property |
kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed |
mg/l(1) |
mg/l(1) |
(2) |
|
Copper (T) |
3.01 |
1.64 |
0.77 |
0.42 |
0.664 |
Lead (T) |
3.09 |
1.52 |
0.79 |
0.39 |
0.859 |
Zinc (T) |
4.45 |
1.68 |
1.14 |
0.43 |
1.05 |
Total phenols |
3.36 |
1.17 |
0.86 |
0.3 |
0.781 |
Oil & grease |
117 |
39.1 |
30 |
10 |
19.5 |
TSS |
148 |
58.6 |
38 |
15 |
39.1 |
pH |
(3) |
(3) |
(3) |
(3) |
(3) |
(1) These concentrations shall be multiplied by the ratio of (0.468/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2) kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed.
(3) Within the range of 7.0 to 10.0 to all times.
TABLE 7
ALUMINUM CASTING SUBCATEGORY
MOLD COOLING OPERATIONS
BPT Effluent Limitations |
|||||
Noncontinuous Direct Dischargers |
|||||
Maximum for any 1 day |
Maximum for monthly average |
Maximum for any 1 day |
Maximum for monthly average |
Annual average |
|
Pollutant or pollutant property |
kg/1,000 kkg (pounds per million pounds) of metal poured |
mg/l(1) |
mg/l(1) |
(2) |
|
Copper (T) |
0.297 |
0.162 |
0.77 |
0.42 |
0.0656 |
Lead (T) |
0.305 |
0.151 |
0.79 |
0.39 |
0.0849 |
Zinc (T) |
0.44 |
0.166 |
1.14 |
0.43 |
0.104 |
Oil & grease |
11.6 |
3.86 |
30 |
10 |
1.93 |
TSS |
14.7 |
5.79 |
38 |
15 |
3.86 |
pH |
(3) |
(3) |
(3) |
(3) |
(3) |
(1) These concentrations shall be multiplied by the ratio of (46.3/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2) kg/1,000 kkg (pounds per million pounds) of metal poured.
(3) Within the range of 7.0 to 10.0 to all times.