Radon Reality in Dillon: Testing and Mitigation Basics

Buying or owning a home in Dillon comes with big mountain perks and a few hidden risks. Radon is one of them. You cannot see or smell it, and levels can be higher in Colorado mountain homes. In this guide, you’ll learn what radon means for Summit County, how to test the right way, and how mitigation works for basements and crawlspaces common in Dillon. Let’s dive in.

Radon in Dillon: What to know

Radon is a colorless, odorless radioactive gas that forms naturally in soil and rock. It can enter homes through small openings in foundations and accumulate indoors. The EPA action level is 4 pCi/L, where mitigation is recommended to reduce exposure. You can find clear guidance on risks and action steps from the U.S. Environmental Protection Agency’s radon page.

Much of Colorado, including Summit County, has elevated radon potential due to local geology and fractured bedrock. Many Dillon homes have finished basements or crawlspaces where radon can collect. Winter heating and closed-house conditions can increase indoor levels, which is common across mountain communities. The Colorado Department of Public Health & Environment (CDPHE) Radon Program tracks statewide risk and offers consumer resources.

How to test in Dillon

Pick the right test type

• Short-term tests. Charcoal canisters, electret ion chambers, or professional continuous monitors run for 2 to 7 days. These are common for real estate transactions and initial screening.
• Long-term tests. Alpha-track or electret detectors stay in place for 90 days to 1 year. These capture seasonal swings and provide a better average.
• Professional monitors. Certified measurement pros use continuous radon monitors that show hourly readings and help diagnose patterns.

For step-by-step instructions and protocols, review EPA guidance on how to test your home.

Set up your test correctly

• Use closed-house conditions for short-term tests. Keep windows and exterior doors closed, except for normal entry and exit, for at least 12 hours before and during testing.
• Place the device in the lowest lived-in level, like a finished basement family room or bedroom. Set it 2 to 6 feet above the floor, away from drafts, exterior walls, and direct sun.
• If your short-term result is near the action level, follow up with another short-term test or a long-term test to confirm.

Where to get kits or help locally

• Local programs. Summit County often supports low-cost or community kit distribution and can point you to trusted resources. Start with Summit County Public Health.
• State resources. The CDPHE Radon Program lists certified professionals and current testing initiatives.
• Retail options. Home improvement stores and reputable online retailers sell EPA-approved kits.
• Certified testers. For real estate transactions, hire a certified measurement professional to run a defensible test and explain the results.

Reading your results

• EPA action level: 4 pCi/L. At or above this level, plan to mitigate.
• If your number is below 4 pCi/L, many homeowners still consider mitigation, especially if results hover around 2 to 4 pCi/L or if you want added peace of mind.
• Remember that radon fluctuates by hour and season. A single short-term test is a snapshot. If your first test is close to 4 pCi/L, confirm with a second test or a long-term test.

You can find clear interpretation tips in the EPA’s radon guidance.

Mitigation basics for Dillon homes

Radon mitigation reduces indoor levels by preventing soil gas from entering living areas and by venting gases safely outside above the roofline.

Basements and slabs: sub-slab depressurization

The most common system is Active Soil Depressurization, sometimes called Sub-slab Depressurization. A contractor creates one or more suction points through the concrete slab or via a sealed sump pit. PVC piping carries air to a continuously running in-line fan, which exhausts gas above the roofline. A small gauge, or manometer, lets you confirm the fan is working.

Crawlspaces: encapsulation and sub-membrane suction

For crawlspaces, pros typically install a durable sealed membrane across the floor and walls, then draw suction from beneath it to a vent stack and fan. This approach controls radon while addressing moisture. Some projects condition the crawlspace as part of the home’s envelope, which requires careful HVAC planning.

Sumps and complex foundations

Sump pits are common entry points. Mitigators often seal the pit or tie it into the radon system. Larger or mixed-foundation homes, such as walkout basements or homes with additions, may need multiple suction points or a hybrid design.

What performance to expect

A well-designed system typically reduces radon by 50 to 99 percent and brings levels below the EPA action level in most homes. Post-installation testing verifies performance, and ongoing retesting every couple of years helps ensure the system continues to work. Learn more in the EPA’s mitigation overview.

Note: If a property uses a private well, ask your contractor about radon-in-water testing and treatment options.

Cost, timing, and permits

Every house is different, but EPA guidance notes that many homes can be fixed for a cost similar to other common repairs, typically ranging from the hundreds to a few thousand dollars depending on complexity. Straightforward installations often take a day, while larger projects can take longer. Roof penetrations, fan placement, and electrical work may require permits and inspections, so check requirements with the Town of Dillon and Summit County building departments.

Hiring the right pro

Look for certification from national credentialing organizations. These directories help you verify credentials and find local providers:

• National Radon Proficiency Program (NRPP)
• National Radon Safety Board (NRSB)

Ask for a written estimate, system design for your foundation type, expected post-mitigation level, warranty, and whether the contractor handles permitting and follow-up testing. Get more than one bid when you can.

Smart questions to ask

• Are you certified through NRPP or NRSB? Can you share your certification number?
• Have you installed systems in homes with basements or crawlspaces like mine in Summit County?
• Do you handle permits and inspections, if required?
• What post-mitigation level do you expect? Do you include follow-up testing?
• What are the warranty terms for the fan and labor?

Simple next steps

1. Assume risk in Dillon and plan to test if a home has not been tested.
2. Use an EPA-approved short-term kit or hire a certified pro for a transaction-grade test.
3. Follow closed-house conditions and place the test in the lowest lived-in level. If you see 4 pCi/L or more, plan mitigation. If results are 2 to 4 pCi/L, confirm with a follow-up test.
4. Hire an NRPP- or NRSB-certified mitigator. Ask for a written design, permit confirmation if needed, warranty, and post-mitigation testing.
5. Retest after installation to confirm results, then test every couple of years or after major renovations.

Trusted resources

• EPA: big-picture guidance on testing, action levels, and mitigation. Start here: EPA radon overview
• Colorado: local maps, kits, and pros. Visit the CDPHE Radon Program
• Summit County: community programs and local updates. See Summit County Public Health
• Certified professionals: verify credentials at NRPP and NRSB

Ready to talk through testing during due diligence, options for a second home, or planning mitigation before listing? Reach out to Unknown Company to Request a Personalized Market Consultation. We can help you move forward with clarity and connect you with trusted local pros.

FAQs

Is radon dangerous in mountain homes like Dillon?

• Yes. Radon is a leading environmental cause of lung cancer, and levels can be elevated in Colorado mountain counties. Testing is the only way to know your level.

What is the EPA action level for radon?

• The EPA recommends mitigation at 4 pCi/L or higher; consider follow-up testing and mitigation discussions when results are around 2 to 4 pCi/L.

Do I need to retest if a previous test was low?

• Yes. Retest every couple of years or after renovations, foundation work, or major HVAC changes, because radon levels can shift with seasons and home use.

How long does a radon mitigation system last?

• Fans run continuously and often last many years; plan for periodic fan replacement and simple checks of the system gauge to confirm operation.

How long does installation take and what does it cost?

• Many systems install in a day, and costs typically range from the hundreds to a few thousand dollars depending on the home and system design.