The Clean Water Act requires that registered biocides discharged to waters of the United States from a point source must be regulated such that water quality-based effluent limits (WQBELs) for that biocide are established in a National Pollutant Discharge Elimination System (NPDES) permit to meet State water quality standards. There must also be compliance with each State’s Antidegradation Policy. Thus, discharge limits of the chemical control compound depend on local, State, and Federal water restrictions as permitted under the NPDES program to regulate the amount of pollutants that may be discharged to waters by each discharger. Effluent guidelines are technology-based and are usually given on a case-by-case basis for individual facilities.
While commercial molluscicide labels may include specific NPDES discharge limits for that compound, many labels point out that the user must obtain an NPDES permit from the appropriate State/Tribal agency or USEPA Regional Office and comply with State water quality requirements.
Products registered as pesticides by the USEPA must be handled and applied within the limits of the label instructions.
Although most molluscicides are biodegradable, some detoxification or deactivation may be required to meet State and Federal discharge requirements. See the topic "Adjuvant/Detoxicant/Deactivant Use.”
Zebra Mussel Chemical Control Guide
The Use Guide Outline