Forecast Rain with Four Competing BMP Failures on a 14-Acre Grading Site
You are inspecting a 14-acre residential grading project in a region forecast to receive 0.6 inch of rain in 14 hours. You find: a 300-foot silt fence segment along the downslope perimeter with 40 feet of fabric sagging and 6 inches of sediment accumulated at the toe; a stabilized construction entrance with 25 feet of trackout on the public road; a concrete washout pit within 15 feet of a storm drain inlet with no liner; and an 80-cubic-yard stockpile of fill without cover. The SWPPP designates the silt fence as a perimeter control and requires daily inspections during rain. The general contractor's superintendent says trackout will be cleaned "after the storm." The concrete subcontractor has a pour scheduled in two hours. You must decide priorities and leave the site with a defensible record.
1. Rank the four findings by corrective-action priority before the forecast rain. State the reasoning for each.
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Rank by pollutant risk, proximity to a receiving water, and time available before rain:
- Concrete washout near the storm drain: highest priority. Concrete washout water is highly alkaline and can be toxic to aquatic life; 15 feet from an inlet with no liner means a short spill path. Stop or relocate the pour until the pit is lined and moved.
- Silt fence sag with 6 inches of sediment: high priority. The design intends this as the downslope perimeter control. Forty feet of sag is a structural failure, and the stored sediment will mobilize in 0.6 inch of rain.
- Trackout on the public road: high priority, but controllable by sweeping. The road is an off-site discharge pathway and the public sees it. Cleaning before rain prevents wash-in to the inlet.
- Uncovered 80-cubic-yard stockpile: moderate to high. The volume is large and will generate sediment-laden runoff; cover or perimeter controls are needed before rain, but it is farther from the inlet than the washout.
The ranking is not the same as the work list. All four need action before rain; the ranking tells you what to stop first and what to verify personally.
2. List immediate field actions and the documentation you would complete before leaving the site.
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Immediate actions:
- Direct the concrete subcontractor to halt the pour until the washout is lined and relocated outside the inlet's immediate drainage path.
- Photograph the washout, inlet, and distance between them; note the absence of a liner.
- Require the silt fence crew to reset the sagging fabric, remove accumulated sediment, and re-anchor the posts.
- Order street sweeping of the 25 feet of trackout, with a repeat sweep after any further tracking.
- Require the stockpile to be covered or contained before the rain.
Documentation before leaving:
- Time-stamped photos with location references.
- A written inspection report listing each deficiency, the specific SWPPP BMP affected, the corrective action, the responsible party, and a deadline.
- A corrective-action log entry that distinguishes "notified" from "verified corrected."
- Names of the superintendent and subcontractor representatives who received the notice.
Do not sign off on a correction you have not seen. The record should show the condition found and the action required, not an assumption that someone will act.
3. The superintendent defers trackout cleanup until after the storm. How do you respond, and what escalation path applies?
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Treat the deferral as a refusal to implement a required control, not a scheduling preference. Explain the consequence in operational terms: 0.6 inch of rain will wash the trackout into the curb inlet, creating an off-site sediment discharge and a likely notice of violation. If the superintendent still refuses, issue a written correction notice with a short, specific deadline tied to the rain forecast, and escalate to the project manager and the owner's representative. If the site permit or contract gives the inspector stop-work authority for imminent discharge, use it for the trackout and the concrete pour. Otherwise, document the refusal, the time, the names, and the potential receiving water, and notify the QSD/QSP and the municipal stormwater contact as required by the project's approved procedures. The key judgment is proportionality: the trackout is cleanable in under an hour, so the cost of refusal is high and the justification for escalation is strong.