Final Inspection Under a Closing Deadline
A final inspection is scheduled for a 4-bedroom, 480-gpd pressure-distributed system. The as-built shows five trenches at 72 ft instead of six at 60 ft, for the same total length of 360 ft. The tank is 1,500 gal; measured scum is 12 in and sludge is 24 in. The outlet baffle has a 3-in gap at the top, and the effluent filter is missing. The pump runs for 4 minutes and delivers about 120 gal; the design dose is 165 gal. A squirt test shows weak flow at the last lateral, and one orifice is plugged with soil. The installer's report says “system meets design, inspection passed” and asks the inspector to sign because the homeowner is closing on the sale tomorrow.
1. Determine whether the system should pass or fail, and justify the decision with the measured findings.
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Fail. The as-built deviates from the approved plan in trench count and length, and the dose is only 120 gal against a 165-gal design-about 73% of the required dose-so distribution is not as designed. The 3-in baffle gap and missing effluent filter are deficiencies. Scum at 12 in plus sludge at 24 in totals 36 in; in a typical 1,500-gal tank with about 72 in of liquid depth, that is 50% of liquid depth and likely exceeds the common 25% scum and 50% sludge limits, so pump-out is required. The plugged orifice and weak last lateral also fail the distribution check.
2. What verification tests and measurements should the inspector perform or require before reconsidering approval?
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Measure tank liquid depth, scum and sludge thickness, outlet invert, baffle integrity, and filter presence. Run the pump and measure delivered volume over time with a calibrated container or flow meter; record dose, run time, off time, alarm operation, and high-water float. Perform a squirt test at every orifice and check lateral level, orifice size, and plugging. Verify as-built trench dimensions, separation, slope, and distribution-box elevations. Record all measurements and photographs. Approval should be based on the corrected system meeting the approved design, not on the closing schedule.
3. How should the inspector respond to the installer's request to sign the report?
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Do not sign the installer's report. The report is inaccurate, and signing it would misrepresent the inspection. Issue an independent report with measured findings, photographs, a fail determination, and required corrections. Tell the homeowner that closing may need to be delayed or handled with an escrow until corrections are verified. If pressured, escalate to a supervisor and the permitting authority. Ethical reporting requires independence and truthfulness; a sale deadline is not a technical basis for approval.