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Oil, gas and geothermal well drilling, cementing and pressure grouting services; construction and installation of pneumatic bulk material handling systems comprised of pipes, tubing, couplings, pumps, blowers, filters, valves, and electrical controls and switches

Oil, gas and geothermal well treatment, perforating fracturing, stimulating and plugging

Engineering, geological estimations and research and computer programming for others, all in the field of oil, gas and geothermal well drilling; testing analysis and treating of oil, gas and geothermal well workings; and oil, gas and geothermal field exploration