7 ft Trench, an Absent Competent Person, and a Sub Who Said "Out by Friday"
You are the GC's superintendent on an addition to an occupied building. At 9:40 a.m. you see two of a subcontractor's laborers working in a 7 ft deep utility trench on the north side. The walls are cut vertical and unstabilized. Spoil is piled 3 ft back from the trench edge and a backhoe idles 12 ft away. The nearest ladder is set 32 ft from where the men are working. The soil is moist cohesive sandy clay over previously excavated fill. Your site safety plan assigns daily excavation inspections to the excavation subcontractor's competent person, who has not been on site for two days. You warned this sub about trench protection last week; their project manager replied, "We'll be out by Friday."
1. Analyze the GC's exposure here. Why isn't this solely the subcontractor's problem?
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On a multi-employer site, OSHA can cite more than the employer of the exposed workers. The controlling employer - the one with general supervisory authority over the site - has a duty to exercise reasonable care to prevent and detect violations, even where it did not create them and does not employ the exposed workers. You are that employer. You also have a general-duty obligation for conditions you knew or should have known about, and you knew: your plan named the inspection responsibility, and you saw the violation with your own eyes.
What you are looking at, requirement by requirement:
- 7 ft depth - over 5 ft, so a protective system (sloping, shoring, or a trench box) is mandatory. Vertical, unstabilized walls: no system at all.
- Spoil at 3 ft from the edge - kept material must be at least 2 ft back, so the spoil itself is passable but its interaction with vibration and surcharge is not.
- Ladder 32 ft away - lateral travel to a means of egress must not exceed 25 ft. It fails.
- Competent person absent two days - daily inspection of excavations, by a competent person, is required before employees enter and as conditions change. No inspection occurred.
- Backhoe idling 12 ft away - equipment vibration and surcharge near a vertical cut in Type B material; also requires consideration.
A cave collapse at 7 ft in Type B soil is a fatality scenario, not a near miss. The sub's schedule promise is irrelevant to your exposure.
2. What do you do in the next ten minutes, and why in that order?
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- Order the men out of the trench. Nothing else happens first. Do not get a tape measure, do not take a photo, do not find the sub's foreman. This is your stop-work authority and you use it before you use anything else. If they resist, they are removed from the site.
- Secure the perimeter. Barricade and flag the trench edges at a safe offset, and shut down or reposition the backhoe so it is not operating at the crest. Two barricades protect the public and the trades who walk that side of the building.
- Notify the sub's PM in writing, immediately, from your phone - timestamp matters more than tone. State what was observed, that work is stopped, and what must be in place before it resumes.
- Notify the owner's representative and your safety director the same hour. On an occupied site with a public exposure, a same-day record is your defense.
- Photograph and log - depth, wall condition, spoil distance, ladder distance, the absent competent person. Do this after the men are out and the area is barricaded.
- Re-inspect before restart: written competent-person inspection, protective system in place with tabulated data, ladder within 25 ft, spoil back, then a restart authorization signed by you.
3. The sub's PM argues the work is nearly done and a trench box would cost them a day. How do you handle the follow-up administratively?
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Do not trade a day of schedule for a fatality risk, and do not let the argument stay verbal.
- Written stop-work, with a stated cure. Identify the specific deficiencies and the specific standard they must meet, and set the condition for restart - not a vague "make it safe."
- Backcharge exposure: if you must supply a trench box, shore, or a competent person to keep the project moving, issue a backcharge notice the same day under the subcontract's safety and indemnity provisions, and notify the surety if the sub refuses.
- Escalate one level above the PM, to the sub's principal, in writing. A PM saying "out by Friday" has made a schedule argument, which means they have not understood they can be removed from the site.
- Assess the whole subcontract, not just this trench. If they cut this corner they cut others - pull their excavation plan, their competent-person designation letter, and their daily inspection records for the last two weeks.
- Correct the program gap. Your site safety plan delegated the daily excavation inspection to the sub's competent person and then never verified it happened for two days. That is a supervisory failure on your side of the line. Name a GC competent person with backup coverage, require the inspection log at the morning coordination meeting, and audit it.
- Follow up in the weekly owner's report. Undocumented good judgment looks like no judgment at all if the trench collapses on Saturday.