What Hempstead County, AR's soil rates for a septic system
Very limited
93% of Hempstead County, AR's surveyed soil comes back "Very limited" in USDA's own SSURGO data, the county's dominant condition for a septic absorption field. Practically, that rules out a simple gravity system for most of the county - 93% of it sits in USDA's most-constrained bucket. Hempstead County covers 727.2 square miles and counts 19,105 residents.
This is a county figure, not a parcel figure
Hempstead 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 Hempstead County.
System cost, conventional vs. engineered
Given Hempstead 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 Hempstead County, AR compares
Nationally, Hempstead County, AR is the 931-most-constrained of 3,058 rated counties for septic soil. Within Arkansas alone it ranks 23 of 75.
Before you act on this
How this rating is built, and its real limits · Conventional vs. engineered septic systems