Underground mine service and support workers perform a range of duties related to the operation of orepasses, chutes and conveyor systems, the construction and support of underground structures, passages and roadways, and the supply of materials and supplies to support underground mining. They are employed by coal, metal and non-metallic mineral mines.

Oil and gas well drilling workers operate drilling and service rig machinery as intermediate members of the rig crew. Oil and gas well services operators drive trucks and operate specialized hydraulic pumping systems to place cement in wells or to treat wells with chemicals, sand mixtures or gases to stimulate production. They are employed by drilling and well service contractors and by petroleum producing companies.