| (iii) Oyster waters should be maintained so that concentrations
of toxic materials do not cause edible species of clams, oysters,
and mussels to exceed accepted guidelines for the protection of public
health. Guidelines are provided by the United States Food and Drug
Administration Action Levels for molluscan shellfish, but additional
information related to human health protection may also be considered
in determining acceptable toxic concentrations.
(4) Additional criteria.
(A) Chemical parameters. Site-specific criteria for
chloride, sulfate, and total dissolved solids are established as averages
over an annual period for either a single sampling point or multiple
(B) pH. Site-specific numerical criteria for pH are
established as absolute minima and maxima.
(C) Temperature. Site-specific temperature criteria
are established as absolute maxima.
(D) Toxic materials. Criteria for toxic materials are
established in §307.6 of this title (relating to Toxic Materials).
(E) Nutrient criteria. Numeric and narrative criteria
to preclude excessive growth of aquatic vegetation are intended to
protect multiple uses such as primary, secondary, and noncontact recreation,
aquatic life, and public water supplies. Nutrient numeric criteria
for specific reservoirs, expressed as concentrations of chlorophyll a in water, are listed in Appendix F of §307.10
of this title.
(5) Additional uses. Other basic uses, such as navigation,
agricultural water supply, industrial water supply, seagrass propagation,
and wetland water quality functions must be maintained and protected
for all water in the state where these uses can be achieved.
|Source Note: The provisions of this §307.7 adopted to be effective July 10, 1991, 16 TexReg 3400; amended to be effective July 13, 1995, 20 TexReg 4701; amended to be effective August 17, 2000, 25 TexReg 7722; amended to be effective July 22, 2010, 35 TexReg 6294; amended to be effective March 6, 2014, 39 TexReg 1450; amended to be effective March 1, 2018, 43 TexReg 1102