40 CFR 421.245: Pretreatment standards for existing sources.

Except as provided in 40 CFR 403.7 and 403.13, any existing 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 existing sources. The mass of wastewater pollutants in secondary nickel process wastewater introduced into a POTW must not exceed the following values:

(a) Slag reclaim tailings.

PSES for the Secondary Nickel Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/kg (pounds per million pounds) of slag input to reclaim process

Chromium (total) 5.653 2.313

Copper 24.410 12.850

Nickel 24.670 16.320

(b) Acid reclaim leaching filtrate.

PSES for the Secondary Nickel Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/kg (pounds per million pounds) of acid reclaim nickel produced

Chromium (total) 2.198 0.899

Copper 9.491 4.995

Nickel 9.590 6.344

(c) Acid reclaim leaching belt filter backwash

PSES for the Secondary Nickel Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/kg (pounds per million pounds) of acid reclaim nickel produced

Chromium (total) 0.528 0.216

Copper 2.278 1.199

Nickel 2.302 1.523