EXH1047037430

+Ur.tedStates Office of Water J_ L(_(_i/_ ' EPA-823-B-S4-005a Env_ronmenta!Protection (4305) - August 1994 Agency _EPA Water Quality Standards Handbook: Second Edition "... to restore and maintain the chemical, physical, and biological integrity of the Nation's waters." Contains Update #1 Section 101 (a) of the Clean Water Act August 1994 AR 037430 1047 APPENDIX L Interim Guidance on Determination and , Use of Water-Effect Ratios for Metals WATER QUALITY STANDARDS HANDBOOK SECOND EDITION AR 037431 FEB 22 1994 EPA-823-B-94-001 SUBJECT: Use of the Water-Effect Ratio in Water Quality Standards FROM: Tudor T. Davies, Director Office of Science and Technology TO: Water Management Division Directors, Regions I - X State Water Quality Standards Program Directors PURPOSE There are two purposes for this memorandum. The first is to transmit the Interim Guidance on the Dete_miDa_0n and use of Water-E_fecD Ratios for Metals. EPA committed to developing this guidance to support implementation of federal standards for those States included in the National Toxics Rule. The second is to provide policy guidance on whether a State's application of a wa_er-effect ratio is a site_specific Criterion adjustment sub_ _oEPA review and al. BACKGROUND In the early 1980's, members of the regulated community expressed concern that EPA's laboratory-derived water quality criteria might not accurately reflect site-specific conditions because of the effects of water chemistry and the ability of species to adapt over time. In response to these concerns, EPA created three procedures to derive site-specific criteria. These procedures were published in the Water Oualitv Standards Handbook. 1983.…

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PSCAA Advisory Council Meeting Agenda
Add to CalendarMWednesday Mar 11, 9:00am - 11:35am
1904 3rd Avenue, Suite 105, Seattle, WA 98101
Call to order – Roll Call – Quorum Established – Land Acknowledgement We would like to acknowledge that our Agency operates in four present-day counties, which are the traditional lands of the Coast Salish people, past and present. This acknowledgement does not take the place of authentic relationships with indigenous communities in our jurisdiction and [...]