If you live on a country road or own acreage in Macoupin County, chances are you have questions about radon and private well water. You want a safe home, clear answers, and simple steps that fit real life here. In this guide, you will learn what radon is, how it connects to well water, when to test, what fixes work, and what Illinois expects in a real estate sale. Let’s dive in.
Radon basics in Macoupin County
Radon is a colorless, odorless radioactive gas that can build up inside homes and raise lung cancer risk over time. There is no known safe level, and risk rises with both concentration and duration of exposure, according to the U.S. EPA. The standard unit is picocuries per liter (pCi/L). The EPA recommends action at or above 4.0 pCi/L and attention even between 2.0 and 4.0 pCi/L.
Macoupin County sits in an area of moderate to high radon potential on the EPA’s radon zone map. Local public health officials emphasize that any home can have elevated radon, regardless of age or neighborhood. The Macoupin County Public Health Department (MCPHD) notes that about one in three local homes have tested high and offers low‑cost test kits through its radon testing program.
Why well water matters
If you rely on a private well, you should know that radon can dissolve into groundwater. When you run showers, laundry, or faucets, some of that radon can release into indoor air. A common rule of thumb is that about 10,000 pCi/L of radon in water can add about 1 pCi/L to indoor air, though actual transfer depends on how your household uses water and how your home is ventilated, per the University of Massachusetts’ radon in private wells guidance.
For most homes, soil gas entering through the foundation is the main source of radon. Still, if your indoor air is elevated and you use a private well, testing the water helps you understand the full picture. MCPHD issues well permits, offers inspections, and can advise on testing through its private well program.
How to test: air and water
When to test
Test the lowest lived‑in level of every home. Test before you buy or soon after move‑in, after major renovations, and every few years as a routine check. If you have a mitigation system, retest regularly to confirm performance.
Air testing options
Short‑term tests give a quick snapshot and are common during real estate inspections, while long‑term tests provide a better year‑round average. The CDC outlines testing types and timing in its step‑by‑step guide. For transactions, many buyers and sellers use an Illinois‑licensed measurement professional, which you can find through the IEMA license lookup.
Well water testing
If your indoor air is high and your home uses a private well, add a water test. You collect a sample and send it to a qualified lab following exact instructions. MCPHD can help you navigate local options through its well water program.
Interpreting results
If your indoor air test reads 4.0 pCi/L or higher, confirm with a second test and plan next steps. Even 2.0 to 4.0 pCi/L deserves attention. The EPA explains how radon exposure affects health and why lowering levels matters in its radon health overview. If air is elevated and you have a well, test the water to see whether waterborne radon is contributing.
Fixing high radon: what works and costs
Air mitigation systems
The most reliable fix for homes with basements or slabs is active sub‑slab depressurization. A fan draws radon from beneath the foundation and vents it outside above the roofline. Systems often reduce indoor radon by 80 to 99 percent, and you should always retest after installation. National averages place installed costs roughly between $800 and $2,500, according to National Radon Program Services.
Treating well water
If testing shows high radon in well water, whole‑house treatment at the point of entry is the goal. Two common options are:
- Aeration systems that bubble air through water and vent the radon outdoors. These deliver high removal rates and usually cost several thousand dollars to install.
- Granular activated carbon (GAC) systems that filter radon from water with carbon media. They typically cost less up front, but the media can accumulate radioactivity at higher levels and needs proper handling.
You can compare methods, when to use them, and cost ranges in this overview of radon removal from water. Always retest after installation to confirm performance.
Buying or selling a home in Illinois
Illinois’ Radon Awareness Act requires sellers of most residential properties to provide the state radon pamphlet and disclose any radon test results they have, but it does not require testing or mitigation. You can read the statute summary here: Illinois Radon Awareness Act. As a buyer, plan a short‑term test during your inspection window and hire an Illinois‑licensed professional if you want third‑party documentation. As a seller, consider pre‑listing testing and keep all records of any mitigation and post‑mitigation results.
Quick Macoupin checklist
- Get an indoor air test for the lowest lived‑in level. If you prefer DIY, MCPHD offers local radon test kits.
- If results are at or above 4.0 pCi/L, confirm with a follow‑up test and request estimates from Illinois‑licensed mitigators via the IEMA license lookup.
- If you use a private well and indoor air is elevated, test your well water and discuss point‑of‑entry treatment options with qualified providers. MCPHD’s well program can guide local steps.
- Keep records of test results, system invoices, and retests. These documents support future sales and long‑term peace of mind.
Ready to plan your next move with confidence? For straight talk on radon and wells during a Macoupin County purchase or sale, reach out to Brad Graham. We know country homes and rural systems, and we are here to help you navigate the process.
FAQs
Do I need a radon test if I live in Macoupin County?
- Yes. The EPA places the area in a moderate to high radon potential zone, and MCPHD reports many homes with elevated levels. Testing is the only way to know your home’s number.
How often should a Macoupin homeowner retest for radon?
- If you do not have a mitigation system and previous tests were low, retest every 2 to 5 years or after major renovations. If you have a system, retest regularly to confirm performance.
If I use a private well, should I test the water for radon too?
- Test the well if indoor air is elevated or if you suspect waterborne radon. Water testing shows whether point‑of‑entry treatment is needed in addition to air mitigation.
Which fix should come first, air or water?
- In most homes, soil gas is the main source, so start with an air mitigation system. If water testing shows high radon and indoor air is still elevated, add water treatment.
What budget should I plan for mitigation?
- Air systems commonly range from about $800 to $2,500 installed. Whole‑house water aeration often costs several thousand dollars, while GAC filters are usually lower cost up front but need proper media handling over time.
