What EPA's radon map says about Pottawattamie County

EPA's own radon map rates Pottawattamie County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Nationally that's the 93rd percentile for radon potential — Pottawattamie County outranks 93% of every county EPA has rated.

Where Pottawattamie County sits nationally

About 93,529 people live in Pottawattamie County, Iowa, spread over 951.284 square miles. Population density there runs about 98 people per square mile. Among counties sharing Pottawattamie County's EPA zone, it outranks 81% of them by population. Geologically, Pottawattamie County is grouped into EPA Region 7 alongside 411 other counties that share its rock and soil setting.

Zone vs. an actual test

Pottawattamie County's predicted average sits above EPA's own action level of 4 pCi/L — the concentration at which EPA recommends fixing a home — versus a national average around 1.3 pCi/L indoors and 0.4 pCi/L outdoors. A Zone 1 rating means testing is worth doing sooner rather than later, but it is still county-wide average, not a reading for any single house — some homes in Pottawattamie County will test well under the action level, and EPA's guidance is to test regardless of zone.

If Pottawattamie County tests above the action level

Mitigation cost doesn't depend on Pottawattamie County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Iowa's state radon program

Pottawattamie County's test kit answers today; a Airthings radon monitor keeps answering for Pottawattamie County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

More on how this number was built

Pottawattamie County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.