Seven federally regulated industrial categories have pretreatment standards established for total toxic organics (TTO). The term TTO is defined as the sum of specific toxic organic compounds found in the process discharge at a concentration of 0.01 mg/l (10 ppb) or more.

Industrial Categories Requiring TTO Limit

Categories affected by a TTO limit include:

Electroplating (40 CFR 413),
• Metal Finishing (40 CFR 433),
• Electrical and Electronic Components (40 CFR 469),
• Metal Molding and Casting (40 CFR 464),
• Coil Coating (40 CFR 465),
• Aluminum Forming (40 CFR 467), and
• Copper Forming (40 CFR 468).

In addition to these seven categories, Pharmaceutical Manufacturing (40 CFR 439) is subject to a specific list of toxic organics with individual discharge limits.

Non-Stormwater Discharge At Industrial Facility Identified During SWPPP Inspection

Non-Stormwater Discharge At Industrial Facility


What Is A Total Toxic Organics Management Plan?

Compliance with the pretreatment standards may be demonstrated in several different ways, including to develop and certify the implementation of a toxic organic management plan (TOMP). The TOMP details Best Management Practices or BMPs to be used to implement the general prohibitions listed in 40 CFR 403.5(a)(1) and specific prohibitions listed in 40 CFR 403.5(b). BMPs could include treatment requirements, operating procedures, and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw materials storage.

This photo shows an example of a Leaking Waste Solvent Hazardous Waste Tank identified during a hazardous waste inspection

Leaking Waste Solvent Hazardous Waste Tank


Caltha LLP provides expert consulting services to facilities nationwide which are subject to Categorical Discharge Standards, or other requirements imposed by the local sewer authority, including the preparation of a a toxic organic management plan (TOMP).

Click here to review an example TOMP project

Request a quote or ask for further information at the Caltha Contact page, or email


Caltha LLP | Your EH&S Compliance, Auditing and EMS/SMS Partner

%d bloggers like this: