Wisconsin Administrative Code › Department of Natural Resources › NR 200-299 - Environmental Protection Wisconsin Pollutant Discharge Elimination System › Chapter NR 273 - Nonferrous metals forming and metal powders › Subchapter II - Magnesium › Section NR 273.022 - Effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available

Current through June 24, 2024
Except as provided in
					 40 CFR 125.30
					 to
					 125.32, any
					 existing point source subject to this subchapter shall achieve the following
					 effluent limitations representing the degree of effluent reduction attainable
					 by application of BPT:
Table 2-1
Magnesium
Rolling Spent Emulsions
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg (pounds per million off-pounds) of
								  magnesium rolled with emulsions
Chromium
0.033
0.014
Zinc
0.109
0.046
Ammonia
9.95
4.37
Fluoride
4.440
1.97
Oil and grease
1.49
0.895
Total suspended solids
3.06
1.46
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all times
Table 2-2
Magnesium
Forging Contact Cooling Water
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg (pounds per million off-pounds) of
								  forged magnesium cooled with water
Chromium
1.27
0.520
Zinc
4.22
1.77
Ammonia
385
170
Fluoride
172
76.3
Oil and grease
57.8
34.7
Total suspended solids
119
56.4
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all times
Table 2-3
Magnesium
Forging Equipment Cleaning Wastewater
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg (pounds per million off-pounds) of
								  forged magnesium
Chromium
0.018
0.007
Zinc
0.059
0.025
Ammonia
5.32
2.34
Fluoride
2.38
1.06
Oil and grease
0.798
0.479
Total suspended solids
1.64
0.778
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all times
Table 2-4
Magnesium
Direct Chill Casting Contact Cooling Water
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg (pounds per million off-pounds) of
								  magnesium cast with direct chill methods
Chromium
1.74
0.711
Zinc
5.77
2.41
Ammonia
527
232
Fluoride
235
105
Oil and grease
79.0
47.4
Total suspended solids
162
77.1
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all times
Table 2-5
Magnesium
Surface Treatment Spent Baths
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg (pounds per million off-pounds) of
								  magnesium surface treated
Chromium
0.205
0.084
Zinc
0.681
0.285
Ammonia
62.1
27.3
Fluoride
27.8
12.3
Oil and grease
9.32
5.59
Total suspended solids
19.1
9.09
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all times
Table 2-6
Magnesium
Surface Treatment Rinse
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg(pounds per million off-pounds) of
								  magnesium surface treated
Chromium
8.32
3.4
Zinc
27.6
11.5
Ammonia
2520
1110
Fluoride
1130
499
Oil and grease
378
227
Total suspended solids
775
369
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all times
Table 2-7
Magnesium
Sawing or Grinding Spent Emulsions
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg (pounds per million off-pounds) of
								  magnesium sawed or ground
Chromium
0.009
0.004
Zinc
0.029
0.012
Ammonia
2.60
1.15
Fluoride
1.16
0.515
Oil and grease
0.390
0.234
Total suspended solids
0.800
0.381
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all times
Table 2-8
Magnesium
Wet Air Pollution Control Scrubber Blowdown
BPT Effluent Limitations
Maximum for any 1 day
Maximum for monthly average
Pollutant or pollutant property
mg/off-kg (pounds per million off-pounds) of
								  magnesium sanded and repaired or forged
Chromium
0.273
0.112
Zinc
0.904
0.378
Ammonia
82.5
36.3
Fluoride
36.9
16.4
Oil and grease
12.4
7.43
Total suspended solids
25.4
12.1
pH
(1)
(1)
(1) Within the range of 7.5 to 10.0 at all
					 times