California Code, Labor Code - LAB § 7954

To assist the unit of safety engineers in determining the safety of tunnel construction and mine operation, the division shall make available at least one industrial hygiene engineer and one chemist.  A laboratory for analysis of dust, gas, vapors, soil, or other materials shall be available to members of this unit.  Contracts to provide for geological and other services may be signed by the division whenever it is necessary to assure safety for employees engaged in mining or tunnel work.