40 CFR 437.42: Effluent limitations attainable by the application of the best practicable control technology currently available (BPT).

(a) Except as provided in 40 CFR 125.30 through 125.32 or § 437.40(b), any existing facility subject to this subpart which combines treated or untreated wastes from subparts A, B, or C of this part may be subject to Multiple Wastestream Subcategory effluent limitations representing the application of BPT set forth in paragraphs (b), (c), (d), or (e) of this section if the discharger agrees to the following conditions in its NPDES permit:

(1) The discharger will meet the applicable Multiple Wastestream Subcategory limitations set forth in (b), (c), (d) or (e);

(2) The discharger will notify its NPDES permit writer at the time of renewal or modification of its permit, of its desire to be subject to the Multiple Waste Subcategory by submitting to the NPDES permit writer an initial certification statement as described in § 437.41(a);

(3) The discharger will submit to its NPDES permitting authority a periodic certification statement as described in § 437.41(b) once a year; and

(4) The discharger will maintain at the office of the facility and make available for inspection the on-site compliance paperwork as described in § 437.41(c).

(b) Combined waste receipts from subparts A, B, and C of this part. (1) As provided in § 437.42(a), any existing point source subject to this paragraph must achieve the following effluent limitations representing the application of BPT:

BPT Limitations

Regulated parameter Maximum daily 1 Maximum monthly avg. 1

Conventional Parameters

BOD5 163 53.0

O&G 127 38.0

pH (2) (2)

TSS 74.1 30.6

Metal Parameters

Antimony 0.249 0.206

Arsenic 0.162 0.104

Cadmium 0.0172 0.0102

Chromium 0.746 0.323

Cobalt 0.192 0.124

Copper 0.500 0.242

Lead 0.350 0.160

Mercury 0.00234 0.000739

Nickel 3.95 1.45

Silver 0.120 0.0351

Tin 0.409 0.120

Titanium 0.0947 0.0618

Vanadium 0.218 0.0662

Zinc 0.497 0.420

Organic Parameters

Acetone 30.2 7.97

Acetophenone 0.114 0.0562

Bis(2-ethylhexyl) phthalate 0.215 0.101

2-Butanone 4.81 1.85

Butylbenzyl phthalate 0.188 0.0887

Carbazole 0.598 0.276

o-Cresol 1.92 0.561

p-Cresol 0.698 0.205

n-Decane 0.948 0.437

Fluoranthene 0.0537 0.0268

n-Octadecane 0.589 0.302

Phenol 3.65 1.08

Pyridine 0.370 0.182

2,4,6-Trichlorophenol 0.155 0.106

1 mg/L (ppm).

2 OSC Within the range 6 to 9.

(2) The following in-plant limitations apply to metal-bearing wastewater containing cyanide:

In-Plant Limitations

Regulated parameter Maximum daily 1 Maximum monthly avg. 1

Cyanide 500 178

1 mg/L (ppm).

(c) Combined waste receipts from subparts A and B of this part. (1) As provided in § 437.42(a), any existing point source subject to this paragraph must achieve the following effluent limitations representing the application of BPT:

BPT Limitations

Regulated parameter Maximum daily 1 Maximum monthly avg. 1

Conventional Parameters

O&G 127 38.0

pH (2) (2)

TSS 74.1 30.6

Metal Parameters

Antimony 0.249 0.206

Arsenic 0.162 0.104

Cadmium 0.0172 0.0102

Chromium 0.746 0.323

Cobalt 0.192 0.124

Copper 0.500 0.242

Lead 0.350 0.160

Mercury 0.00234 0.000739

Nickel 3.95 1.45

Silver 0.120 0.0351

Tin 0.409 0.120

Titanium 0.0947 0.0618

Vanadium 0.218 0.0662

Zinc 2.87 0.641

Organic Parameters

Bis(2-ethylhexyl) phthalate 0.215 0.101

Butylbenzyl phthalate 0.188 0.0887

Carbazole 0.598 0.276

n-Decane 0.948 0.437

Fluoranthene 0.0537 0.0268

n-Octadecane 0.589 0.302

1 mg/L (ppm).

2 Within the range 6 to 9.

(2) The following in-plant limitations apply to metal-bearing wastewater containing cyanide:

In-Plant Limitations

Regulated parameter Maximum daily 1 Maximum monthly avg. 1

Cyanide 500 178

1 mg/L (ppm).

(d) Combined waste receipts from subparts A and C of this part. (1) As provided in § 437.42(a), any existing point source subject to this paragraph must achieve the following effluent limitations representing the application of BPT:

BPT Limitations

Regulated parameter Maximum daily 1 Maximum monthly avg. 1

Conventional Parameters

BOD 5 163 53.0

O&G 205 50.2

pH (2) (2)

TSS 60.0 31.0

Metal Parameters

Antimony 0.249 0.206

Arsenic 0.162 0.104

Cadmium 0.474 0.0962

Chromium 15.5 3.07

Cobalt 0.192 0.124

Copper 0.865 0.757

Lead 1.32 0.283

Mercury 0.00234 0.000739

Nickel 3.95 1.45

Silver 0.120 0.0351

Tin 0.409 0.120

Titanium 0.0947 0.0618

Vanadium 0.218 0.0662

Zinc 0.497 0.420

Organic Parameters

Acetone 30.2 7.97

Acetophenone 0.114 0.0562

2-Butanone 4.81 1.85

o-Cresol 1.92 0.561

p-Cresol 0.698 0.205

Phenol 3.65 1.08

Pyridine 0.370 0.182

2,4,6-Trichlorophenol 0.155 0.106

1 mg/L (ppm).

2 Within the range 6 to 9.

(2) The following in-plant limitations apply to metal-bearing wastewater containing cyanide:

In-Plant Limitations

Regulated parameter Maximum daily 1 Maximum monthly avg. 1

Cyanide 500 178

1 mg/L (ppm).

(e) Combined waste receipts from subparts B and C of this part. As provided in § 437.42(a), any existing point source subject to this paragraph must achieve the following effluent limitations representing the application of BPT:

BPT Limitations

Regulated parameter Maximum daily 1 Maximum monthly avg. 1

Conventional Parameters

BOD5 163 53.0

O&G 127 38.0

pH (2) (2)

TSS 74.1 30.6

Metal Parameters

Arsenic 2.95 1.33

Cadmium 0.0172 0.0102

Chromium 0.746 0.323

Cobalt 56.4 18.8

Copper 0.500 0.242

Lead 0.350 0.160

Mercury 0.0172 0.00647

Tin 0.335 0.165

Zinc 0.497 0.420

Organic Parameters

Acetone 30.2 7.97

Acetophenone 0.114 0.0562

Bis(2-ethylhexyl) phthalate 0.215 0.101

2-Butanone 4.81 1.85

Butylbenzyl phthalate 0.188 0.0887

Carbazole 0.598 0.276

o-Cresol 1.92 0.561

p-Cresol 0.698 0.205

n-Decane 0.948 0.437

Fluoranthene 0.0537 0.0268

n-Octadecane 0.589 0.302

Phenol 3.65 1.08

Pyridine 0.370 0.182

2,4,6-Trichlorophenol 0.155 0.106

1 mg/L (ppm).

2 Within the range 6 to 9.