415.542—Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT).

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 practicable control technology currently available (BPT):

Subpart BB—Sodium Bisulfite

Pollutant or pollutant property	BPT effluent limitations
Pollutant or pollutant property	Maximum for any 1 day	Average of daily values for 30 consecutive days
	Kg/kkg (or pounds per 1,000 lb) of product
TSS	0.32	0.080
COD	3.8	0.95
Chromium (T)	0.0020	0.00063
Zinc (T)	0.0051	0.0015
pH	(1)	(1)
1 Within the range 6.0 to 9.0.