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Install and get inspected before backfilling

Installation quality decides how long a system lasts. Most authorities inspect tanks and drainfields before they are covered.

How

1. Keep heavy machinery off the drainfield and reserve area before, during and after construction to avoid compacting the soil.
2. Do not install or work on drainfields when the soil is wet.
3. Check that trench bottoms and distribution devices are level so effluent spreads evenly.
4. Fit risers to the surface and check baffles are in place.
5. Book the authority inspection before backfilling, and photograph everything with a tape measure in shot.
6. Divert roof and paved-area runoff away from the drainfield.

Safety: Trench collapse is a serious risk. Never enter trenches deeper than your local safety rules allow without shoring.

Sources

1. Decentralized Systems Technology Fact Sheet: Septic Tank Soil Absorption Systems (EPA 932-F-99-075). US Environmental Protection Agency, accessed 2026-11
2. Septic Tank Maintenance (EC 1343). Oregon State University Extension Service, accessed 2026-11

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