Stuck Pump, Wet Pit, and Unsafe Pulling
At a farm in St. Lawrence County, a two-person crew is pulling a 2-hp submersible pump from a 300-foot, 6-inch well. The pump is stuck at 280 feet. The wellhead is in a 4-foot-deep concrete pit with 8 inches of standing water; a portable generator sits on wet grass 15 feet away. The hoist is mounted on a backhoe bucket, and the cable has a nick with exposed conductor. The helper is standing in the pit guiding the drop pipe by hand while the operator bumps the hoist. The pressure tank is not valved off, and the pump leads are still connected to the control box. The farmhand wants to use a chain and another truck to pull harder. The nearest hospital is 35 minutes away. The crew has no lockout tags, no GFCI, and no fall protection.
1. Identify the principal hazards and state the immediate stop-work actions.
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The hazards include electrical shock from the damaged cable, an ungrounded generator, and energized pump leads; mechanical failure from using a backhoe bucket as a hoist and shock-loading a stuck pump; stored water pressure because the tank is not isolated; a fall and drowning or contamination risk in the wet pit; and manual crushing or amputation risk from hands on the pipe under load. Treat the pit as a confined space until tested and controlled; do not enter it. Immediate actions: stop pulling, lower or secure the suspended load, shut off and lock out the pump circuit, disconnect the pump leads, isolate and bleed the pressure tank, clear personnel from the pit, and remove the generator from wet ground or shut it down. Do not use a truck or chain to jerk the pump; that converts a stuck-pump problem into a cable or rigging failure.
2. Describe a safe sequence for freeing or replacing the pump.
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First complete lockout/tagout and verify zero energy. Isolate the pressure tank and relieve pressure. Set up a rated hoist or tripod with a proper base, use pipe slips and a safety line, and keep hands off the pipe while it is under tension. Use the manufacturer's or a fishing-tool method to work the pump free; do not shock-load the cable. If the pump cannot be freed, call a drilling or pump contractor with proper fishing and rigging equipment. Replace the damaged cable and any questionable splices, use GFCI protection and a grounded generator, and keep cords out of water. Control the pit with ventilation and atmospheric testing if entry is unavoidable, and use a harness, tripod, and attendant. Only after the pump is secured and the electrical system is repaired should the well be returned to service.
3. If the pit must be entered, what controls are necessary?
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Assume the pit is a permit-required confined space unless a competent evaluation shows otherwise. Test the atmosphere for oxygen, combustible gas, hydrogen sulfide, and carbon monoxide before entry and continuously during work. Ventilate mechanically. Provide a harness, retrieval line, tripod, and a trained attendant outside the pit. Keep the generator and fuel outside the pit and away from the opening. Use nonconductive PPE and GFCI-protected equipment. Have rescue equipment and a rescue plan ready; the nearest hospital being 35 minutes away makes self-rescue and rapid retrieval critical. If any test fails or conditions change, exit and reassess. Never use the pit as a workspace simply because it is only 4 feet deep and already has water in it.