Acidizing oil and gas field wells on a contract basis

Building oil and gas well foundations on a contract basis

Building, erecting, repairing, and dismantling oil and gas field rigs and derricks on a contract basis

Cementing oil and gas well casings on a contract basis

Chemically treating oil and gas wells (e.g., acidizing, bailing, swabbing) on a contract basis

Cleaning oil and gas field lease tanks on a contract basis

Cleaning out (e.g., bailing out, steam cleaning, swabbing) wells on a contract basis

Cleaning wells on a contract basis

Cleaning, repairing, and dismantling oil and gas field lease tanks on a contract basis

Contract services (except site preparation and related construction contractor activities) for oil and gas fields

Core cutting in oil and gas wells, on a contract basis

Core drilling, exploration services, oil and gas field

Cutting cores in oil and gas wells on a contract basis

Derrick building, repairing, and dismantling at oil and gas fields on a contract basis

Dismantling of oil well rigs on a contract basis

Drill-stem testing in oil, gas, dry, and service well drilling on a contract basis

Drilling rat holes and mouse holes at oil and gas fields on a contract basis

Drilling shot holes at oil and gas fields on a contract basis

Drilling site preparation at oil and gas fields on a contract basis

Excavating mud pits, slush pits, and cellars at oil and gas fields on a contract basis