Physical Demands: When working in the field, must possess the strength, stamina, and mobility to perform light to medium physical work; to sit, stand, and walk on level, uneven, or slippery surfaces; frequently reach, twist, turn, kneel, bend, stoop, squat, crouch, grasp, and make repetitive hand movement in the performance of daily duties; to climb and descend ladders; to operate various equipment and tools; to operate a motor vehicle and visit various District sites; and vision to locate utilities and read printed materials. • Observes various tests of raw materials or finished products as required by the approved plans and specifications, including, but not limited to: • Concrete test cylinders • Concrete slump tests • Hydrostatic pressure tests • Air and mandrel tests • Sand equivalent and graduation tests • Soils compaction tests • Spark tests • Conducts bacteriological sampling of water systems and relinquish the samples to the IRWD laboratory.