Statutes, codes, and regulations
Oklahoma Administrative Code
Title 252 - Department of Environmental QualityChapter 740 - Implementation of Oklahoma's Water Quality Standards
Subchapter 5 - Implementation of Numerical Criteria to Protect Fish and Wildlife from Toxicity Due to Conservative Substances
Section 252:740-5-4 - pH and hardness dependent toxicity

Okla. Admin. Code § 252:740-5-4

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Current through Vol. 41, No. 19, June 17, 2024
Section 252:740-5-4 - pH and hardness dependent toxicity

The criteria for some of the substances listed in OAC 252:730-5-12(f)(6) are hardness or pH dependent. The segment-averaged pH in Appendix B of this Chapter shall be used to determine the criterion if there is insufficient site-specific data to determine receiving stream pH. The mean hardness of the receiving stream, collected near the outfall but not affected by the discharge (as CaCO3) may be used if at least 10 monthly samples were collected over a ten-month period. The segment-averaged hardness in Appendix B of this Chapter shall be used in the determination of the criterion if there is insufficient site-specific data to determine receiving stream hardness. If the required pH or hardness is not specified for a particular waterbody segment, appropriate data from surrounding waterbody segments may be used.

Okla. Admin. Code § 252:740-5-4

Adopted by Oklahoma Register, Volume 40, Issue 6, December 1, 2022, eff. 10/25/2022
Adopted by Oklahoma Register, Volume 40, Issue 24, September 1, 2023, eff. 9/15/2023