The 7½-Foot Trench: Slough-In at 4:15
Columbus, Ohio - 90°F, no rain in nine days. A utility crew is installing 8-inch sanitary line in a trench 7 ft 6 in deep, 5 ft wide, 60 ft long, cut through undisturbed clay and silt that the subcontractor's competent person classified as Type B. At 2:00 p.m. that competent person leaves for another job and does not return; no protective system has been installed. Spoil is piled 4 ft high with its toe 2 ft 6 in from the trench edge, and the excavator is parked 12 ft back. A pump runs continuously, but 6 in of water stands in the bottom. The only ladder is at the north end; the pipe layer is working 34 ft south of it. At 4:15 p.m. the east wall sloughs and buries him to the knees. Crew members dig him out; he is admitted overnight with a fractured tibia.
1. List each hazard in this trench, the OSHA requirement it violates, and the threshold that makes the requirement apply.
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Protective system - 1926.652(a)(1). At 5 ft and deeper, employees in an excavation must be protected by sloping, benching, shoring, or a shield unless the competent person makes a documented determination that the excavation is in stable rock. The depth is 7 ft 6 in, so the exception is unavailable regardless of soil type. For Type B soil, sloping at 1:1 (45°) or an engineered system is required.
Spoil and equipment placement - 1926.651(j)(2). The toe of the spoil pile must be at least 2 ft from the edge; here it is 2 ft 6 in from the edge but piled 4 ft high, which imposes a surcharge load right at the crest of a wall that has no protective system. The excavator at 12 ft is acceptable for vibration and surcharge only if the wall is protected.
Egress - 1926.651(c)(2). A ladder is required within 25 ft of lateral travel; the worker is 34 ft away, and egress is required at 4 ft of depth.
Water - 1926.651(h)(1). Standing water requires special precautions and, absent protection, removal of employees.
Competent person inspections - 1926.651(k). Daily before entry and after any event that could change conditions. The competent person left at 2:00 p.m. and no one inspected again, which is a distinct violation from the missing protective system.
2. What must the employer report to OSHA and when, and what must appear on the OSHA 300 log?
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OSHA reporting - 29 CFR 1904.39. Two thresholds have to be separated. A fatality must be reported within 8 hours. An in-patient hospitalization for treatment (not just observation) must be reported within 24 hours of learning of it. This worker was admitted overnight, so the 24-hour clock applies. The report goes to OSHA by telephone to the nearest area office or through the online reporting portal, and the employer must supply the establishment name, location, time and date of the event, injured person's name, a brief description, and a contact person.
OSHA 300 log - 1904.7 and 1904.29. The case is work-related and resulted in medical treatment beyond first aid plus days away from work, so it is recordable. Enter it within 7 calendar days of learning of the event, and complete the 301 Incident Report. Do not treat the report to OSHA as satisfying the log entry, or the log entry as satisfying the report - they are separate obligations with separate clocks.
Practical note: reporting the hospitalization does not require the employer to admit fault, and the employer should not delay the call while investigating.
3. The general contractor argues the trench was only 7½ feet and 'clay holds fine.' How should the competent person respond, and what must be true before anyone re-enters?
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On the argument: 'Clay holds fine' is folklore, not a protective system. The standard does not ask whether soil looks stable; it asks for a classification by a competent person and a protective system matched to that classification. Increasing depth is not even the controlling variable here - water, a 4-ft spoil pile at the crest, and nine days of drying followed by a pump running in the bottom all change the load on that wall. The slough is the proof: an unprotected Type B wall failed in a 7½-ft cut.
Before re-entry:
- A competent person inspects the excavation and the adjacent areas after the slough, because the failure changed conditions.
- A protective system is installed: 1:1 sloping, benching for Type B, or a shield rated for the depth.
- Spoil is moved back beyond 2 ft from the crest or hauled out.
- Water is controlled and the bottom is stable enough to stand on.
- A ladder is placed within 25 ft of each worker.
- Entry is limited to authorized personnel, and the excavation is barricaded or marked.
Note that 1926.651(k)(2) requires removal of employees from the excavation if the competent person finds evidence of a situation that could result in a cave-in - that authority is the whole point of the designation.