30 CFR § 75.1319 Weight of explosives permitted in boreholes in bituminous and lignite mines.
(a) The total weight of explosives loaded in any borehole in
bituminous and lignite mines shall not exceed 3 pounds except when blasting
solid rock in its natural deposit.
(b) The total weight of explosives loaded in a borehole less than 6
feet deep in bituminous and lignite mines shall be reduced by 1/2 pound for
each foot of borehole less than 6 feet.
