e
For acute conditions the default assumption is that salmonids could be present in cold water segments and should be protected, and that salmonids do not need
to be protected in warm water segments. For chronic conditions, the default assumptions are that early life stages could be present all year in cold water segments
and should be protected. In warm water segments, the default assumption is that early life stages are present and should be protected only from April 1 through
August 31. These assumptions can be modified by the commission on a site-specific basis where appropriate evidence is submitted
f
Unless the stability of the chromium valence state in receiving waters can be clearly demonstrated, the standard for chromium should be in terms of chromium
VI. In no case can the sum of the instream levels of Hexavalent and Trivalent Chromium exceed the water supply standard of 50 ug/l total chromium in those
waters classified for domestic water use
g
Selenium is a bioaccumulative metal and subject to a range of toxicity values depending upon numerous site-specific variables
3 Surface Water Quality and Analysis
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