What Sullivan County, MO's soil rates for a septic system

Very limited

Soil across 98.8% of Sullivan County, MO rates "Very limited" in USDA's septic-absorption-field interpretation. That reading means a conventional system is a poor bet here - 98.8% of Sullivan County lands in the strictest "very limited" bucket USDA uses. Sullivan County covers 647.982 square miles and counts 5,750 residents.

This is a county figure, not a parcel figure

Sullivan County's rating is an average across the whole county, not a promise about any one lot inside it. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Sullivan County.

System cost, conventional vs. engineered

Given Sullivan County's rating, plan for the engineered-system range rather than the conventional one. The engineered-system range, $10,000-$40,000 (mound or aerobic treatment), is the more realistic number to plan around, against $3,000-$8,000 for a conventional system on the rare lot that passes.

How Sullivan County, MO compares

Nationally, Sullivan County, MO is the 125-most-constrained of 3,058 rated counties for septic soil. Within Missouri alone it ranks 19 of 114.

Further reading

How this rating is built, and its real limits · Conventional vs. engineered septic systems