What does the installer or site evaluator need from me before breaking ground?

At minimum the permitting authority requires a completed application, a legal description of the property, the site evaluation report, and a scale drawing showing the OSSF, all structures served, and every feature and separation distance from §§285.30(b) and 285.91(10) (30 TAC Chapter 285, §§285.3, 285.5). TCEQ's application form asks for the property legal description with verification attached (deed, plat map, or survey), acreage and plat date, the source of water (private well or named public supplier), and the number of bedrooms and living area in square feet (TCEQ OSSF Permit Application, form TCEQ-0235). Counties add to that: Williamson County requires the warranty deed, a survey, the full OSSF design plan with soil report and site plan, separate copies of the soil evaluation and site plan, a floor plan with the address marked, and — for aerobic systems — the maintenance contract and maintenance affidavit (Williamson County); Travis County's plot plan must show property lines and dimensions, all proposed buildings/pools/driveways/patios, wells and OSSFs within 150 ft including on adjoining property, potable water lines, north arrow, nearest public road, easements, creeks and ponds, slopes ≥15%, and the 25-year floodplain (Travis County OSSF permit).

Reviewed August 2026. Links go to the sources this answer was checked against.