25 Pa. Code § 89.112

Current through Register Vol. 54, No. 50, December 14, 2024

Section 89.112 - Impoundments

An impoundment shall be designed in accordance with the United States Natural Resources Conservation Service's Pennsylvania Field Office Technical Guide, Section IV, Standards 350, "Sediment Basin," and 378, "Pond," or United States Natural Resources Conservation Service Technical Release No. 60, "Earth Dams and Reservoirs," whichever is applicable. The standards are incorporated by reference. In addition to the requirements in "Sediment Basin," a minimum static safety factor of 1.3 is required. Each impoundment shall be certified that it has been constructed and is being maintained as designed and in accordance with the approved plan and all applicable performance standards. These structures shall also meet the following requirements:

(1) The entire embankment, including the surrounding areas disturbed by construction, shall be stabilized with respect to erosion by a vegetative cover or other means immediately after the embankment is completed. The active upstream face of the embankment where water is being impounded may be riprapped or otherwise stabilized. Areas in which the vegetation is not successful or where rills and gullies develop shall be repaired and revegetated in accordance with § 89.86 (relating to revegetation).

(2) Ponds shall be examined annually by the operator for structural weakness, erosion and other hazardous conditions. If structural weakness, erosion or other hazardous conditions exist, the operator shall immediately notify the Department.

(3) Plans for enlargement, reduction in size, reconstruction or other modification of dams or impoundments shall be submitted to the Department and shall comply with the requirements of § 86.52 (relating to permit revisions). Except when a modification is required to eliminate an emergency condition constituting a hazard to public health, safety or the environment, the plans shall be approved by the Department before modification begins.

(4) Emergency spillways may not discharge unless precipitation exceeds a 10-year, 24-hour rainfall event. Precipitation includes:

(i) Snow melt, or a combination snow melt and rainfall event.

(ii) Multiple rainfall events occurring within the design drawdown period of the pond.

25 Pa. Code § 89.112

The provisions of this § 89.112 adopted July 30, 1982, 12 Pa.B. 2473, effective 7/31/1982, 12 Pa.B. 2382; amended June 15, 1990, 20 Pa.B. 3383, effective 7/27/1991, 21 Pa.B. 3316; amended December 15, 1995, effective 12/16/1995, 25 Pa.B. 5821; amended March 13, 2020, effective 3/14/2020, 50 Pa.B. 1508.

The provisions of this § 89.112 amended under the Surface Mining Conservation and Reclamation Act (52 P.S. §§ 1396.1-1396.19a); The Bituminous Mine Subsidence and Land Conservation Act (52 P.S. §§ 1406.1-1406.21); The Clean Streams Law (35 P.S. §§ 691.1-691.1001); section 1920-A of The Administrative Code of 1929 (71 P.S. § 510-20); and section 3.2 of the Coal Refuse Disposal Control Act (52 P.S. § 30.53b).

This section cited in 25 Pa. Code § 89.89 (relating to permanent impoundments).