---
kind: "section"
citation: "30 C.F.R. § 780.35"
title: "30"
number: "780.35"
heading: "Disposal of excess spoil."
url: "https://uscodex.org/cfr/30/780.35"
---

# §780.35. Disposal of excess spoil.

- (a) Each application shall contain descriptions, including appropriate maps and cross section drawings, of the proposed disposal site and design of the spoil disposal structures according to [30 CFR 816.71-816.74](/cfr/30/816.71-816.74.md). These plans shall describe the geotechnical investigation, design, construction, operation, maintenance, and removal, if appropriate, of the site and structures.
- (b) Except for the disposal of excess spoil on pre existing benches, each application shall contain the results of a geotechnical investigation of the proposed disposal site, including the following:
  - (1) The character of bedrock and any adverse geologic conditions in the disposal area,
  - (2) A survey identifying all springs, seepage, and ground water flow observed or anticipated during wet periods in the area of the disposal site;
  - (3) A survey of the potential effects of subsidence of the subsurface strata due to past and future mining operations;
  - (4) A technical description of the rock materials to be utilized in the construction of those disposal structures containing rock chimney cores or underlain by a rock drainage blanket; and
  - (5) A stability analysis including, but not limited to, strength parameters, pore pressures and long-term seepage conditions. These data shall be accompanied by a description of all engineering design assumptions and calculations and the alternatives considered in selecting the specific design specifications and methods.
- (c) If, under [30 CFR 816.71(d)](/cfr/30/816.71.md?p=d), rock-toe buttresses or key-way cuts are required, the application shall include the following:
  - (1) The number, location, and depth of borings or test pits which shall be determined with respect to the size of the spoil disposal structure and subsurface conditions; and
  - (2) Engineering specifications utilized to design the rock-toe buttress or key-way cuts which shall be determined in accordance with [paragraph (b)(5)](#b-5) of this section.

## Notes

### Amendments

[79 FR 76229, Dec. 22, 2014, as amended at 81 FR 93330, Dec. 20, 2016; 82 FR 54949, Nov. 17, 2017]

### Authority

Authority: 30 U.S.C. 1201 et seq. and 16 U.S.C. 470 et seq.

### Source

Source: 44 FR 15357, Mar. 13, 1979, unless otherwise noted.

### Amendments

[79 FR 76229, Dec. 22, 2014, as amended at 81 FR 93330, Dec. 20, 2016; 82 FR 54949, Nov. 17, 2017]