40 CFR § 429.95 - Pretreatment standards for existing sources (PSES).

Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart which introduces process wastewater pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and meet the following pretreatment standards for existing sources (PSES):

Subpart H

[PSES Effluent Limitations]

Pollutant or pollutant property	Maximum for any 1 day (mg/l)
Oil and grease	100
Copper	5
Chromium	4
Arsenic	4

In cases where POTWs find it necessary to impose mass limitations, the following equivalent mass limitations are provided as guidance.

Subpart H

[PSES Effluent Limitations; grams per cu m of production]

Pollutant or pollutant property	Maximum for any 1 day
Oil and grease	20.5
Copper	.62
Chromium	.41
Arsenic	.41