Water Treatment
Publicly Owned Treatment Works
Maximum Achievable Control Technology
Environmental Protection Agency
An A. & L. Shatto Advisory
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The Clean Air Act as Amended 1990 Section 112 requires Maximum Achievable Control Technology (MACT) promulgation for many categories. Publicly Owned Treatment Works (POTW) is one of these.  The Regulation resides in 40 CFR 63 Subpart VVV. The "Hammer date" was May 15,1999.  This regulation is intended to control the release of any or all of 188 Hazardous Air Pollutants (HAPs). The HAPs are not considered to originate at the POTW, but are assumed to be in the industrial and commercial wastestreams entering the collection system.

If you accept a wastestream which contains sufficient HAPs, you must control the emissions.  If you are treating a wastestream for a facility in order to control a HAP in accordance with a National Emission Standard for Hazardous Air Pollutants (NESHAP), then you are an agent of that facility and an "Industrial POTW".  Legally very interesting! The date that this affects you is determined by the date for the specific NESHAP or the date of initial wastestream acceptance.

Compliance consists of:

• Installation and operation of emission control devices of MACT quality, determined by the NESHAP.

• Performance tests.

• Routine monitoring - wastestream and air emissions.

• Record-keeping

• Reporting.

• Maintenance and inspection program.

This requires permitting for construction (installation) and operation of the devices.  The permitting may be Part 70 (Title V) federally enforceable permitting, not State.

How do you know what your status is? You must have detailed knowledge in the following areas:

• All wastestreams entering your collection system, including industrial, commercial, and other facilities.

• Analytical data of your wastestream for all 188 HAPs, including Volatile Organic Compounds (VOCs) and Base/Neutral/Acid (BNA) organic analyses.

A well run pretreatment program and routine influent monitoring should give you what you need to make your determination.  Based on the information you have, emissions modeling can be done to see if you hit either the 10 tons per year for a single HAP or 25 tons per year for any combination of HAPs thresholds.

Control technology is not specified by the EPA, but must be equal to the standard of control set by the EPA for the NESHAP, which is based on the best performing technology.  Consider what is involved. First you must capture the HAPs and then treat to something over 85% removal Who pays?  Depends on the status you want and the degree of shared responsibility you want with your industrial and commercial customers.