Permit Scope Versus What Is Actually Built
A permit was issued for a conventional trench absorption field with three 60-foot trenches. During inspection you find the contractor has installed two 80-foot trenches and connected them to a distribution box intended for three laterals. The contractor says the designer approved the change verbally because the soils were better than expected and the shorter field would not fit the cleared area. No revised drawing has been submitted. The installed field is in a different location than shown on the approved plan, closer to a slope break. The homeowner has already paid the contractor in full.
1. How do you handle the field change administratively, and what is the status of the installation?
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The installation is not approvable as built. A verbal designer approval is not a permit modification. The approved plan governs until a revised plan is submitted and the permit is revised.
Steps:
- Stop and document. Record the as-built configuration (two 80-foot trenches, D-box sized for three, relocated field) with measurements and photos.
- Do not approve or reject the design merits yourself. The change may be technically sound, but it is outside the permitted scope and outside your authority to accept verbally.
- Require a revised submittal from the designer showing the actual layout, trench lengths, D-box configuration, and the relocated field relative to the slope break, with supporting soil information.
- Route it through plan review and issue a permit revision if it complies.
- Notify all parties in writing of the deficiency and the path to compliance; the homeowner's payment status is irrelevant to the code decision.
The permit file should show the deficiency notice, the required corrective action, and the re-inspection trigger.
2. What specific technical concerns does the relocated, reconfigured field raise that the revised submittal must address?
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The revision must demonstrate:
- Setbacks and separation at the new location, including distance to the slope break, property lines, wells, and watercourses.
- Slope stability and surfacing. A field near a slope break risks surfacing or slope failure; the designer must show the field is set back appropriately and that the slope is stable.
- Hydraulic balance. Two 80-foot trenches provide 160 feet of lateral versus the permitted 180 feet across three trenches. Confirm the reduced length still meets the required infiltrative area for the design flow and soil loading rate.
- Distribution. A D-box built for three laterals feeding two means one outlet is unused or the flow splits unevenly; the submittal must show how flow is balanced (e.g., a two-way D-box or flow-equalizing devices).
- 100 percent replacement area at the new location, if required.
Approval should be conditioned on these being shown, not assumed.