---
kind: "section"
citation: "30 C.F.R. § 75.1322"
title: "30"
number: "75.1322"
heading: "Stemming boreholes."
url: "https://uscodex.org/cfr/30/75.1322"
---

# §75.1322. Stemming boreholes.

- (a) Only noncombustible material shall be used for stemming boreholes.
- (b) Stemming materials other than water stemming bags shall be tamped to fill the entire cross sectional area of the borehole.
- (c) Stemming material shall contact the explosive cartridge nearest the collar of the borehole.
- (d) Each borehole 4 or more feet deep shall be stemmed for at least 24 inches.
- (e) Each borehole less than 4 feet deep shall be stemmed for at least half the depth of the borehole.
- (f) When blasting off the solid in bituminous and lignite mines, only pliable clay dummies shall be used for stemming.
- (g) The diameter of a water stemming bag shall be within 1/4 of an inch of the diameter of the drill bit used to drill the borehole.
- (h) Water stemming bags shall be constructed of tear-resistant and flame-resistant material and be capable of withstanding a 3-foot drop when filled without rupturing or developing leaks.

## Notes

### Source

Source: 53 FR 46786, Nov. 18, 1988, unless otherwise noted.

### Authority

Authority: 30 U.S.C. 811, 813(h), 957.

### Source

Source: 35 FR 17890, Nov. 20, 1970, unless otherwise noted.