Facilities that discharge wastewater to a publicly owned treatment works?

Facilities that discharge wastewater to a POTW (publicly owned treatment works) are known as subject to pretreatment requirements and indirect dischargers. EPA's pretreatment program regulations are originated at 40 CFR Part 403. The term "discharger" will be used in this document to signify a permittee, applicant, discharger, or other entity regulated under EPA's wastewater regulations. Under the regulations every discharger is required to monitor its effluent for compliance with any and all relevant Federal and State discharge boundaries, and use the 304(h) methods to demonstrate compliance with NPDES and pretreatment program limitations. The Regulatory authorities have accepted primacy for execute the Clean Water Act and with that responsibility have authority to be more restrictive than the federal regulations.

The 304(h) processes are incorporated or published by reference at 40 CFR Part 136 or 40 CFR Parts 405 - 500 and are usually known as the "Part 136 methods." For numerous analytes, these methods comprise methods published by EPA by the U.S. Geological Survey (USGS) by voluntary consensus standards bodies for example ASTM International (formerly known as the American Society for Testing and Materials International) as well as by manufacturers of instruments and testing devices.

The Part 136 methods comprise methods approved for use in all of EPA's ambient water programs and wastewater (example- methods for general use). A method approved for common uses are listed in tables at 40 CFR Part 136.3(a) including