30 CFR § 75.212 Rehabilitation of areas with unsupported roof.
(a) Before rehabilitating each area where a roof fall has occurred or
the roof has been removed by mining machines or by blasting--
(1) The mine operator shall establish the clean up and
support procedures that will be followed;
(2) All persons assigned to perform rehabilitation work
shall be instructed in the clean-up and support procedures; and
(3) Ineffective, damaged or missing roof support at the
edge of the area to be rehabilitated shall be replaced or other equivalent
(b) All persons who perform rehabilitation work shall be experienced
in this work or they shall be supervised by a person experienced in
rehabilitation work who is designated by the mine operator.
(c) Where work is not being performed to rehabilitate an area in
active workings where a roof fall has occurred or the roof has been removed
by mining machines or by blasting, each entrance to the area shall be
supported by at least one row of posts on not more than 5-foot centers, or
equally effective support.