25 Pa. Code § 91.38
Except when the use of an algicide, herbicide or fish control chemical would be in violation of a specific order or permit, the use is authorized only in the following instances:
The provisions of this § 91.38 issued under section 5 of The Clean Streams Law (35 P. S. § 691.5); and section 1920-A of The Administrative Code of 1929 (71 P. S. § 510-20).
The provisions of this § 91.38 adopted January 28, 2000, effective January 29, 2000, 30 Pa.B. 521.