30 CFR § 57.3401
Examination of ground conditions.
Persons experienced in examining and testing for loose ground shall be
designated by the mine operator. Appropriate supervisors or other designated
persons shall examine and, where applicable, test ground conditions in areas
where work is to be performed, prior to work commencing, after blasting, and
as ground conditions warrant during the work shift. Underground haulageways
and travelways and surface area highwalls and banks adjoining travelways
shall be examined weekly or more often if changing ground conditions
warrant.
For further information: See MSHA's Program Policy Manual