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Additional sources of WET program information

EPA WET Test Methods and toxicity information

Test methods designed specifically for measuring whole effluent toxicity (WET) have been codified at 40 CFR part 136 [60 FR 53529; Oct. 16, 1995]. Three EPA WET Methods Manuals (two freshwater, one marine) were incorporated by reference into 40 CFR part 136 in the 1995 rule. On Nov. 19, 2002, EPA revised these methods and made available updated method manual editions.

As regulations, use of these methods and adherence to the specific test procedures outlined in these documents is required when monitoring WET under the National Pollutant Discharge Elimination System (which is where Wisconsin's WPDES permit program originates). The state of Wisconsin Aquatic Life Toxicity Testing Methods Manual is intended to comply with the requirements of 40 CFR part 136, and all permittees and laboratories must follow the requirements found in this document in order to submit tests for compliance with a WPDES permit and/or to maintain laboratory certification or registration.

The following websites contain information related to EPA and NELAC WET requirements and toxicity information:

  • EPA WET Methods Manuals and WET Guidance Documents
  • The ECOTOXicology knowledgebase (ECOTOX) is a comprehensive, publicly available knowledgebase providing single chemical environmental toxicity data on aquatic life, terrestrial plants and wildlife.
  • The NELAC Institute (TNI) is a 501(c)(3) nonprofit organization whose mission is to foster the generation of environmental data of known and documented quality through an open, inclusive and transparent process that is responsive to the needs of the community. The TNI home page contains documents and files on TNI’s constitution and bylaws, all the current standards, as well as all proposed changes to these documents. Also included are a history of NELAC, minutes of recent meetings, announcements of upcoming conferences and meetings, related information, the NELAC directory and an open forum for discussion of NELAC issues.