Hyde County, SD radon potential

EPA places Hyde County in Zone 1 - Highest Potential — a predicted county-wide average indoor radon level above 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 66th percentile for radon potential — Hyde County outranks 66% of every county EPA has rated.

Hyde County by the numbers

Hyde County, South Dakota is home to about 1,215 people across 860.629 square miles. Population density there runs about 1 people per square mile. Within its own EPA zone, Hyde County is bigger by population than 1% of the counties that share it. Hyde County falls in EPA Radon Region 8, one of 291 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Outdoor air nationally averages about 0.4 pCi/L, indoor air about 1.3 pCi/L — Hyde County's Zone 1 prediction clears both of those and EPA's fix-it threshold besides. Some Hyde County homes will test comfortably under the action level despite the county's Zone 1 rating — the only way to know which kind of home you have is an actual test.

Testing and mitigation in Hyde County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find South Dakota's state radon program

For Hyde County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Hyde County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

Where Hyde County's figures come from

Hyde County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Hyde County carries, the zone explainer covers what it does and doesn't tell you about any one house.