Septic suitability in Apache County, AZ
Very limited
USDA puts Apache County, AZ at "Very limited" for septic absorption fields, the dominant reading across 66.5% of the county's soil. Practically, that rules out a simple gravity system for most of the county - 66.5% of it sits in USDA's most-constrained bucket. The county spans 11,198.31 square miles, home to 64,800 people.
What this number does and doesn't tell you
Two lots a mile apart in Apache County can carry different soil, even though they share one countywide rating. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.
Apache County: conventional vs. engineered cost
66.5% of Apache 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, Apache County, AZ ranks 2,571 most-constrained nationally, and 10 of 15 within Arizona.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems