40 CFR 463.32: 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 must achieve the effluent limitations guidelines (i.e., mass of pollutant discharged) representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available, which are calculated by multiplying the average process water usage flow rate for the finishing water processes at a point source times the following pollutant concentrations:

Subpart C

[Finishing water]

Concentration used to calculate BPT effluent limitations

Pollutant or pollutant property Maximum for any 1 day (mg/l) Maximum for monthly average (mg/l)

TSS 130 37

pH (1) (1)

1 Within the range of 6.0 to 9.0 at all times.

The permit authority will obtain the average process water usage flow rate for the finishing water processes from the permittee.