30 CFR § 75.389
Mining into inaccessible areas.
(a)(1) The operator shall develop and follow a plan for mining into areas
penetrated by boreholes drilled under §75.388
(2) Mining shall not resume into any area penetrated by boreholes
until conditions in the penetrated area can be determined under
and the plan for mining-through into the
area has been approved by the district manager.
(3) A copy of the procedures to be followed shall be posted near the
site of the mining-through operations and the operator shall explain these
procedures to all miners involved in the operations.
(b) The procedures specified in the plan shall include--
(1) The method of ventilation, ventilation controls, and the air
quantities and velocities in the affected working section and working
(2) Dewatering procedures to be used if a penetrated area contains a
water accumulation; and
(3) The procedures and precautions to be followed during
(c) Except for routine mining-through operations that are part of a
retreat section ventilation system approved in accordance with
and (x), the following provisions
(1) Before and during mining-through operations, a certified person
shall perform air quality tests at intervals and at locations necessary to
protect the safety of the miners.
(2) During mining-through operations, only persons involved in these
operations shall be permitted in the mine; and
(3) After mining-through, a certified person shall determine that the
affected areas are safe before any persons enter the underground areas of the mine.