More information from O*NET OnLine:

Wellhead Pumpers - 53-7073.00

O*NET-SOC Description

Operate power pumps and auxiliary equipment to produce flow of oil or gas from wells in oil field.

53-0000	Transportation and Material Moving Occupations
53-7000	Material Moving Workers
53-7070	Pumping Station Operators
53-7073.00	Wellhead Pumpers

47-5012.00	Rotary Drill Operators, Oil and Gas
47-5013.00	Service Unit Operators, Oil and Gas
47-5071.00	Roustabouts, Oil and Gas
51-8013.00	Power Plant Operators
51-8013.04	Hydroelectric Plant Technicians
51-8021.00	Stationary Engineers and Boiler Operators
51-8092.00	Gas Plant Operators
51-8093.00	Petroleum Pump System Operators, Refinery Operators, and Gaugers
53-7071.00	Gas Compressor and Gas Pumping Station Operators
53-7072.00	Pump Operators, Except Wellhead Pumpers

Attach pumps and hoses to wellheads.
Change water filters.
Gauge oil and gas production.
Mix acids, chemicals, or dry cement as required for a specific job.
Monitor control panels during pumping operations to ensure that materials are being pumped at the correct pressure, density, rate, and concentration.
Monitor pumps and flow lines for gas and fluid leaks.
Open valves to return compressed gas to bottoms of specified wells to repressurize them and force oil to surface.
Operate engines and pumps to shut off wells according to production schedules, and to switch flow of oil into storage tanks.
Perform routine maintenance on vehicles and equipment.
Prepare trucks and equipment necessary for the type of pumping service required.
Repair gas and oil meters and gauges.
Start compressor engines and divert oil from storage tanks into compressor units and auxiliary equipment to recover natural gas from oil.
Supervise oil pumpers and other workers engaged in producing oil from wells.
Unload and assemble pipes and pumping equipment, using hand tools.

Calculate weights, volumes or other characteristics of materials.
Connect hoses to equipment or machinery.
Control pumps or pumping equipment.
Direct material handling or moving activities.
Inspect gas systems or components to identify leaks or other potential hazards.
Install machine or equipment replacement parts.
Install parts, assemblies, or attachments in transportation or material handling equipment.
Maintain vehicles in good working condition.
Measure equipment outputs.
Monitor equipment gauges or displays to ensure proper operation.
Monitor equipment operation to ensure proper functioning.
Prepare chemicals for work application.
Repair precision devices or workpieces.
Set up laboratory or field equipment.