What Cumberland County, NC's soil rates for a septic system
Very limited
In Cumberland County, NC, 68.7% 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 68.7% of the county. Cumberland County, NC is 652.566 square miles with a population of 338,430.
What Cumberland County's reading doesn't cover
USDA's survey covers the whole of Cumberland County, NC at once, not any single address. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Cumberland County will actually do.
What a system would cost here
With 68.7% of Cumberland 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.
How Cumberland County, NC compares
Nationally, Cumberland County, NC is the 2,508-most-constrained of 3,058 rated counties for septic soil. Within North Carolina alone it ranks 55 of 97.
Further reading
How this rating is built, and its real limits · Conventional vs. engineered septic systems