(a) For all Wyoming surface waters, pollution attributable to the activities of man shall not be present in amounts which will cause the pH to be less than 6.5 or greater than 9.0 standard units.
(b) For all Class 1, 2 and 3 waters, pollution attributable to the activities of man shall not change the pH to levels which result in harmful acute or chronic effects to aquatic life, directly or in conjunction with other chemical constituents, or which would not fully support existing and designated uses.
020-1 Wyo. Code R. § 1-26
Amended, Eff. 4/24/2018.