40 CFR 420.123: Effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable (BAT).

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

(a) Galvanizing, terne coating and other coatings—(1) Strip, sheet, and miscellaneous products scrubbers.

Subpart L

Pollutant or pollutant property BAT effluent limitations

Maximum for any 1 day Average of daily values for 30 consecutive days

Kg/kkg (pounds per 1,000 lb) of product

Lead 0.00113 0.000376

Zinc 0.00150 0.000500

Chromium (hexavalent) 1 0.000150 0.0000501

1 The limitations for hexavalent chromium shall be applicable only to galvanizing operations which discharge wastewater from the chromate rinse step.

(2) [Reserved]

(b) Galvanizing and other coatings—(1) Wire products and fasteners.

Subpart L

Pollutant or pollutant property BAT effluent limitations

Maximum for any 1 day Average of daily values for 30 consecutive days

Kg/kkg (pounds per 1,000 lb) of product

Lead 0.00451 0.00150

Zinc 0.00601 0.00200

Chromium (hexavalent) 1 0.000601 0.000200

1 The limitations for hexavalent chromium shall be applicable only to galvanizing operations which discharge wastewaters from the chromate rinse step.

(2) [Reserved]

(c) Fume scrubbers.

Subpart L

Pollutant or pollutant property BAT effluent limitations

Maximum for any 1 day Average of daily values for 30 consecutive days

Kg per day

Lead 0.0368 0.0123

Zinc 0.0491 0.0164

Chromium (hexavalent) 1 0.00490 0.00163

1 The limitations for hexavalent chromium shall be applicable only to galvanizing operations which discharge wastewaters from the chromate rinse step.

The above limitations shall be applicable to each fume scrubber associated with any of the coating operations specified above.