Hanson County, SD's soil, for a septic absorption field
Very limited
In Hanson County, SD, 90.2% of the surveyed land carries a "Very limited" rating for a standard septic drain field. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 90.2% of the county. Hanson County, SD is 434.582 square miles with a population of 3,477.
What Hanson County's reading doesn't cover
Nothing about Hanson County, SD's SSURGO figure applies to a specific address - it's a county-wide average. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Hanson County will actually do.
What a system would cost here
With 90.2% of Hanson County rating "Very limited", a standard gravity system is not a safe assumption here. 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.
Hanson County's rank among South Dakota counties
Nationally, Hanson County, SD is the 1,252-most-constrained of 3,058 rated counties for septic soil. Within South Dakota alone it ranks 25 of 66.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems