Union County, SC: the USDA septic-suitability picture

Very limited

Union County, SC: USDA's soil survey calls 62.2% of the county "Very limited" for a septic leach field. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 62.2% of the county. For scale: 513.604 square miles and 26,678 people call Union County home.

Before you rely on this for one lot

USDA's survey covers the whole of Union County, SC at once, not any single address. The real answer for one lot is still a site-specific perc test, running about $750-$1,850 (typically near $1,300).

Budgeting for a system in Union County, SC

Union County's soil reading pushes the likely outcome toward an engineered system rather than a conventional one. Conventional systems run $3,000-$8,000 where they pass; where they don't, engineered alternatives (mound or aerobic treatment, whichever the health department requires) run $10,000-$40,000 - budget toward the higher figure until a perc test says otherwise.

Where this sits nationally

Among the 3,058 rated counties on this site, Union County, SC ranks 2,685 most-constrained nationally, and 32 of 46 within South Carolina.

Further reading

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