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Key Concepts of Impaired Waters and Developing TMDLs

An Online Introductory Course

What is the 303(d) list? What is a total maximum daily load (TMDL)? How is a TMDL developed? The answers to these and many other questions related to TMDLs can be found in Listing Impaired Waters and Developing TMDLs, a Web-based training course designed by EPA's Office of Science and Technology for state and tribal employees and the general public. Information on your state's 303(d) list and TMDLs can be found on EPA's ATTAINS site or on your state's water quality agency Web site.

This course is not only an introductory unit for those with little familiarity with impaired waters, the 303(d) list and TMDLs but also a refresher course for those with experience in the subject. The course concludes with a brief quiz intended to touch on some of the key concepts. The main pages and quiz are designed to take users approximately 20 minutes to complete. (Note that quiz responses are not scored or recorded.)



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