La. Admin. Code tit. 43 § XV-5395

Current through Register Vol. 50, No. 9, September 20, 2024
Section XV-5395 - Coal Processing Waste: Dams and Embankments-Design and Construction
A. The design of each dam and embankment constructed of coal processing waste or intended to impound such waste shall comply with the requirements of §5333. A and C, modified as follows.
1. The design freeboard between the lowest point on the embankment crest and the maximum water elevation shall be at least 3 feet.
2. The dam and embankment shall have a minimum safety factor of 1.5 for the partial pool with steady seepage saturation conditions, and the seismic safety factor shall be at least 1.2.
3. The dam or embankment foundation and abutments shall be designed to be stable under all conditions of construction and operation of the impoundment. Sufficient foundation investigations and laboratory testing shall be performed to determine the safety factors of the dam or embankment for all loading conditions appearing in §5395. A.2 and for all increments of construction.
4. Each dam or embankment constructed of coal mine waste or intended to impound coal mine waste that meets the criteria of 30 CFR 77.216(a) shall have sufficient spillway capacity to safely pass, adequate storage capacity to safely contain, or a combination of storage capacity and spillway capacity to safely control, the probable maximum precipitation of a six-hour precipitation event, or greater event as specified by the office.
B. Spillways and outlet works shall be designed to provide adequate protection against erosion and corrosion. Inlets shall be protected against blockage.
C. Dams or embankments constructed of or impounding waste materials shall be designed so that at least 90 percent of the water stored during the design precipitation event can be removed within a 10-day period.
D. For dams or embankments constructed of or impounding coal mine waste, at least 90 percent of the water stored during the design precipitation event shall be removed within the 10-day period following the design precipitation event.

La. Admin. Code tit. 43, § XV-5395

Promulgated by the Department of Natural Resources, Office of Conservation, LR 5:395 (December 1979), amended LR 14:441 (July 1988), LR 20:447 (April 1994).
AUTHORITY NOTE: Promulgated in accordance with R.S. 30:901-932.