Breckinridge County, KY: the USDA septic-suitability picture
Very limited
USDA puts Breckinridge County, KY at "Very limited" for septic absorption fields, the dominant reading across 74.7% of the county's soil. Practically, that rules out a simple gravity system for most of the county - 74.7% of it sits in USDA's most-constrained bucket. The county spans 569.725 square miles, home to 21,221 people.
What this number does and doesn't tell you
This is a countywide, area-weighted figure across every soil survey map unit in Breckinridge County, KY - never a reading for one specific parcel. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.
Breckinridge County: conventional vs. engineered cost
74.7% of Breckinridge County carrying a "Very limited" reading changes the realistic budget here. 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, Breckinridge County, KY ranks 2,300 most-constrained nationally, and 98 of 119 within Kentucky.
Further reading
How this rating is built, and its real limits · Conventional vs. engineered septic systems