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Subpart B—Primary Aluminum Smelting Subcategory

§ 421.20 Applicability: description of the primary aluminum smelting subcategory.

The provisions of this subpart are applicable to discharges resulting from the production of aluminum from alumina in the Hall-Heroult process.

§ 421.21 Specialized definitions.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in part 401 of this chapter, shall apply to this subpart.

(b) The term product shall mean hot aluminum metal.

(c) If a permittee chooses to analyze for benzo(a)pyrene using any EPA-approved method, any “non-detected” measurements shall be considered zeroes for the purpose of determining compliance with this regulation.

[49 FR 8792, Mar. 8, 1984, as amended at 52 FR 25556, July 7, 1987]

§ 421.22 Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable technology currently available (BPT):

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
Metric units—kg/kkg of product
English units—lbs/thousand lbs of product
Fluoride 2.0 1.0
Total Suspended solids 3.0 1.5
pH (1) (1)
1 Within the range of 6 to 9 at all times.

[49 FR 8792, Mar. 8, 1984; 49 FR 29794, July 24, 1984]

§ 421.23 Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.

Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable:

(a) Subpart B—Anode and Cathode Paste Plant Wet Air Pollution Control

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of paste produced
Benzo(a)pyrene 0.005 0.002
Antimony .263 .117
Nickel .075 .050
Aluminum .831 .369
Fluoride 8.092 3.591

(b) Subpart (B)—Anode Contact Cooling and Briquette Quenching.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of anodes cast
Benzo(a)pyrene 0.007 0.003
Antimony .403 .180
Nickel .115 .077
Aluminum 1.277 .566
Fluoride 12.440 5.518

(c) Subpart (B)—Anode Bake Plant Wet Air Pollution Control (Closed Top Ring Furnace).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of anodes baked
Benzo(a)pyrene 0.146 0.067
Antimony 8.346 3.719
Nickel 2.378 1.600
Aluminum 26.420 11.720
Fluoride 257.300 114.200

(d) Subpart B—Anode Bake Plant Wet Air Pollution Control (Open Top Ring Furnace With Spray Tower Only).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of anodes baked
Benzo(a)pyrene 0.002 0.001
Antimony .097 .043
Nickel .028 .019
Aluminum .306 .136
Fluoride 2.975 1.320

(e) Subpart B—Anode Bake Plant Wet Air Pollution Control (Open Top Ring Furnace With Wet Electrostatic Precipitator and Spray Tower).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of anodes baked
Benzo(a)pyrene 0.025 0.011
Antimony 1.409 .628
Nickel .402 .270
Aluminum 4.461 1.979
Fluoride 43.440 19.270

(f) Subpart B—Anode Bake Plant Wet Air Pollution Control (Tunnel Kiln).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of anodes baked
Benzo(a)pyrene 0.038 0.018
Antimony 2.197 .979
Nickel .626 .421
Aluminum 6.953 3.084
Fluoride 67.710 30.050

(g) Subpart B—Cathode Reprocessing (Operated With Dry Potline Scrubbing and Not Commingled With Other Process or Nonprocess Waters).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Antimony 420.400 189.200
Cyanide 157.600 70.060
Nickel 80.570 35.030
Aluminum 273.200 122.600
Fluoride 29,430.000 13,310.000

(h) Subpart B—Cathode Reprocessing (Operated With Dry Potline Scrubbing and Commingled With Other Process or Nonprocess Waters).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Antimony 67.610 30.120
Cyanide 157.600 70.060
Nickel 19.270 12.960
Aluminum 214.000 94.930
Fluoride 2,084.000 924.800

(i) Subpart B—Cathode Reprocessing (Operated With Wet Potline Scrubbing).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of cryolite recovered
Benzo(a)pyrene .000
Antimony .000 .000
Cyanide .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000

(j) Subpart B—Potline Wet Air Pollution Control (Operated Without Cathode Reprocessing).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene 0.028 0.013
Antimony 1.618 .721
Nickel .461 .310
Aluminum 5.120 2.271
Fluoride 49.860 22.130

(k) Subpart B—Potline Wet Air Pollution Control (Operated With Cathode Reprocessing and Not Commingled With Other Process or Nonprocess Waters).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene 0.028 0.013
Antimony 10.060 4.525
Cyanide 3.771 1.676
Nickel 1.928 .838
Aluminum 6.537 2.933
Fluoride 703.900 318.500

(l) Potline Wet Air Pollution Control Cooperated With Cathode Reprocessing and Commingled With Other Process or Nonprocess Wastewaters).

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene 0.028 0.013
Antimony 1.618 .721
Cyanide 3.771 1.676
Nickel 0.461 .310
Aluminum 5.120 2.271
Fluoride 49.860 22.130

(m) Subpart B—Potroom Wet Air Pollution Control.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene 0.056 0.026
Antimony 3.204 1.428
Nickel .913 .614
Aluminum 10.140 4.499
Fluoride 98.770 43.830

(n) Subpart B—Potline SO2 Emissions Wet Air Pollution Control.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene 0.045 0.021
Antimony 2.588 1.153
Nickel .738 .496
Aluminum 8.194 3.634
Fluoride 79.790 35.400

(o) Subpart B—Degassing Wet Air Pollution Control.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene (1) (1)
Antimony 5.036 2.244
Nickel 1.435 .965
Aluminum 15.940 7.071
Fluoride 155.300 68.880
1 There shall be no discharge allowance for this pollutant.

(p) Subpart B—Pot Repair and Pot Soaking.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000

(q) Subpart B—Direct Chill Casting Contact Cooling.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum product from direct chill casting
Benzo(a)pyrene (1) (1)
Antimony 2.565 1.143
Nickel .731 .492
Aluminum 8.120 3.602
Fluoride 79.080 35.090
1 There shall be no discharge allowance for this pollutant.

(r) Subpart B—Continuous Rod Casting Contact Cooling.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum product from rod casting
Benzo(a)pyrene (1) (1)
Antimony .201 .089
Nickel .057 .038
Aluminum .636 .282
Fluoride 6.188 2.746
1 There shall be no discharge allowance for this pollutant.

(s) Subpart B—Stationary Casting or Shot Casting Contact Cooling.

BAT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum product from stationary casting or shot casting
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000

[49 FR 8792, Mar. 8, 1984, as amended at 52 FR 25556, July 7, 1987]

§ 421.24 Standards of performance for new sources.

Any new source subject to this subpart shall achieve the following new source performance standards:

(a) Subpart B—Anode and Cathode Paste Plant Wet Air.

Pollution Control—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of paste produced
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000
Oil and grease .000 .000
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(b) Subpart B—Anode Contact Cooling and Briquette Quenching.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of anodes cast
Benzo(a)pyrene 0.007 0.003
Antimony .403 .180
Nickel .115 .077
Aluminum 1.277 .566
Fluoride 12.440 5.518
Oil and grease 2.090 2.090
Total suspended solids 3.135 2.508
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(c) Subpart B—Anode Bake Plant Wet Air Pollution Control.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of anodes baked
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000
Oil and grease .000 .000
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(d) Subpart B—Cathode Reprocessing (Operated With Dry Potline Scrubbing and Not Commingled With Other Process or Nonprocess Waters).

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Antimony 420.400 189.200
Cyanide 157.600 70.060
Nickel 80.570 35.030
Aluminum 273.200 122.600
Fluoride 29,430.000 13,310.000
Oil and grease 350.300 350.300
Total suspended solids 2,172.000 945.800
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(e) Subpart B—Cathode Reprocessing (Operated With Dry Potline Scrubbing and Commingled With Other Process or Nonprocess Waters).

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Antimony 67.610 30.120
Cyanide 157.600 70.060
Nickel 19.270 12.960
Aluminum 214.000 94.930
Fluoride 2,084.000 924.800
Oil and grease 350.300 350.300
Total suspended solids 2,172.000 945.800
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(f) Subpart B—Potline Wet Air Pollution Control.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000
Oil and grease .000 .000
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(g) Subpart B—Potroom Wet Air Pollution Control.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000
Oil and grease .000 .000
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(h) Subpart B—Potline SO2 Emissions Wet Air Pollution Control.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) aluminum produced from electrolytic reduction
Benzo(a)pyrene 0.045 0.021
Antimony 2.588 1.153
Nickel .738 .496
Aluminum 8.194 3.634
Fluoride 79.790 35.400
Oil and grease 13.410 13.410
Total suspended solids 20.120 16.090
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(i) Subpart B—Degassing Wet Air Pollution Control.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000
Oil and grease .000 .000
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(j) Subpart B—Pot Repair and Pot Soaking.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000
Oil and grease .000 .000
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

(k) Subpart B—Direct Chill Casting Contact Cooling.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum product from direct chill casting
Benzo(a)pyrene (1) (1)
Antimony 2.565 1.143
Nickel .731 .492
Aluminum 8.120 3.602
Fluoride 79.080 35.090
Oil and grease 13.290 13.290
Total suspended solids 19.940 15.950
pH (2) (2)
1 There shall be no discharge allowance for this pollutant.
2 The pH shall be maintained within the range of 7.0 to 10.0 at all times except for those situations when this waste is discharged separately and without commingling with any other waste-water in which case the pH shall be within the range of 6.0 to 10.0 at all times.

(l) Subpart B—Continuous Rod Casting Contact Cooling.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum product from rod casting
Benzo(a)pyrene (1) (1)
Antimony .201 .089
Nickel .057 .038
Aluminum .636 .282
Fluoride 6.188 2.746
Oil and grease 1.040 1.040
Total suspended solids 1.560 1.248
pH (2) (2)
1 There shall be no discharge allowance for this pollutant.
2 Within the range of 7.0 to 10.0 at all times.

(m) Subpart B—Stationary Casting or Shot Casting Contact Cooling.

NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of aluminum product from stationary casting or shot casting
Benzo(a)pyrene .000
Antimony .000 .000
Nickel .000 .000
Aluminum .000 .000
Fluoride .000 .000
Oil and grease .000 .000
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.0 to 10.0 at all times.

[49 FR 8792, Mar. 8, 1984; 49 FR 26739, June 29, 1984, as amended at 52 FR 25558, July 7, 1987]

§ 421.25 [Reserved]

§ 421.26 Pretreatment standards for new sources.

Except as provided in 40 CFR 403.7, any new source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for new sources. The mass of wastewater pollutants in primary aluminum process wastewater introduced into a POTW shall not exceed the following values:

(a) Subpart B—Anode and Cathode Paste Plant Wet Air Pollution Control.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of paste produced
Benzo(a)pyrene .000
Nickel .000 .000
Fluoride .000 .000

(b) Subpart B—Anode Contact Cooling and Briquette Quenching.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of anodes cast
Benzo(a)pyrene 0.007 0.003
Nickel .115 .077
Fluoride 12.440 5.518

(c) Subpart B—Anode Bake Plant Wet Air Pollution Control.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of anodes baked
Benzo(a)pyrene .000
Nickel .000 .000
Fluoride .000 .000

(d) Subpart B—Cathode Reprocessing (Operated With Dry Potline Scrubbing and Not Commingled With Other Process or Nonprocess Waters).

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Cyanide 157.600 70.060
Nickel 80.570 35.030
Fluoride 29,430.000 13,310.000

(e) Subpart B—Cathode Reprocessing (Operated With Dry Potline Scrubbing and Commingled With Other Process or Nonprocess Waters).

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Cyanide 157.600 70.060
Nickel 19.270 12.960
Fluoride 2,084.000 924.800

(f) Subpart B—Potline Wet Air Pollution Control.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Nickel .000 .000
Fluoride .000 .000

(g) Subpart B—Potroom Wet Air Pollution Control.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Nickel .000 .000
Fluoride .000 .000

(h) Subpart B—Potline SO2 Emissions Wet Air Pollution Control.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene 0.045 0.021
Nickel .738 .496
Fluoride 79.790 35.400

(i) Subpart B—Degassing Wet Air Pollution Control.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Nickel .000 .000
Fluoride .000 .000

(j) Subpart B—Pot Repair and Pot Soaking.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of aluminum produced from electrolytic reduction
Benzo(a)pyrene .000
Nickel .000 .000
Fluoride .000 .000

(k) Subpart B—Direct Chill Casting Contact Cooling.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of aluminum product from direct chill casting
Benzo(a)pyrene (1) (1)
Nickel .731 .492
Fluoride 79.080 35.090
1 There shall be no discharge allowance for this pollutant.

(l) Subpart B—Continuous Rod Casting Contact Cooling.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum product from rod casting
Benzo(a)pyrene (1) (1)
Nickel .057 .038
Fluoride 6.188 2.746
1 There shall be no discharge allowance for this pollutant.

(m) Subpart B—Stationary Casting or Shot Casting Contact Cooling.

PSNS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pound per million pounds) of aluminum product from stationary casting or shot casting
Benzo(a)pyrene .000
Nickel .000 .000
Fluoride .000 .000

[49 FR 8792, Mar. 8, 1984; 49 FR 26739, June 29, 1984, as amended at 52 FR 25559, July 7, 1987]

§ 421.27 [Reserved]