Uranium in Well Water: What Colorado Homeowners Need to Know

Dustin Bartel
Oct 2, 2023
4 min read

Updated: Jul 22

By Healthy Home Solutions | Serving Conifer, Evergreen & the Foothills

Why Uranium Matters in Mountain Well Water

Uranium is a naturally occurring metal found in the granite-rich bedrock of the Rocky Mountain region—including Conifer, Evergreen, and surrounding foothills. Nearly all private wells in our area draw water from fractured bedrock aquifers, where uranium and other minerals are present in the rock itself. As water moves through these cracks and fractures, it can dissolve uranium and carry it into your well.

How Does Uranium Get Into Well Water?

Geology, Not Construction: Uranium in well water is a direct result of the local geology. The granite and crystalline rocks beneath our feet contain uranium, which leaches into groundwater as water flows through natural fractures in the bedrock.
Aquifer Depth & Location: Uranium concentrations can vary even between neighboring wells, making regular testing essential. Well construction (depth, casing, etc.) is important for other contaminants, but does not influence whether uranium is present—if your well draws from uranium-rich rock, it’s at risk.
Regional Reality: This is a widespread issue throughout the Rocky Mountain region, not just isolated properties.

Health Risks of Uranium in Drinking Water

Kidney Health: The most significant risk from uranium in drinking water is chemical toxicity, particularly damage to the kidneys. The kidneys filter uranium from the blood, and long-term exposure can impair their function.
Cancer Risk: Uranium is radioactive and classified as a carcinogen by the EPA and World Health Organization, though the cancer risk at typical environmental levels is lower than the risk of kidney damage.
No Immediate Symptoms: Uranium is tasteless, odorless, and colorless. Only laboratory testing can detect its presence.
Sensitive Groups: Children, pregnant women, and people with pre-existing kidney conditions may be more vulnerable to uranium’s effects.

What Levels Are Safe?

The EPA has recognized that the only truly safe level of uranium in drinking water is zero. Because uranium is both chemically toxic and radioactive, even very low levels can present some risk—especially over long-term exposure. The EPA’s Maximum Contaminant Level Goal (MCLG) for uranium is therefore set at zero, reflecting the fact that any exposure is considered to carry potential health risks.

However, when it comes to enforceable regulations, the EPA must also consider the limits of available water treatment technology and the practicalities of nationwide implementation. In the year 2000, the EPA established the Maximum Contaminant Level (MCL) for uranium at 0.03 mg/L (30 parts per billion). This standard was set as close to zero as feasible, based on the best available treatment technology and cost considerations at that time.

In summary:

EPA Public Health Goal (MCLG): Zero uranium—no known or expected risk at this level.
EPA Legal Limit (MCL): 0.03 mg/L (30 ppb)—the enforceable standard, based on what was achievable with technology in 2000.
Local Action: Healthy Home Solutions recommends addressing any detection at or above the MCL, and encourages regular testing even at lower levels, as sensitive individuals may be at risk.

Remember, while the MCL is the legal threshold, the safest approach is to minimize uranium exposure as much as possible.

How Are We Exposed?

Drinking and Cooking Water: The main route for most people is through ingestion of water from private wells. Uranium can also be found in some root vegetables grown in uranium-rich soils.
Other Routes: Inhalation is a minor exposure route for the general population, more relevant for those working in uranium mining or processing.

What Do Uranium Test Results Mean?

Below 0.03 mg/L: Meets EPA standard, but consider retesting annually.
At or Above 0.03 mg/L: Action recommended—consider available treatment options.
Testing: Only a certified laboratory can accurately measure uranium levels. Home test kits are not reliable for uranium.
Levels Can Change: Uranium concentrations can fluctuate over time due to changes in groundwater flow, seasonal variation, or increased well usage. Annual testing is best practice.

Solutions Available for Uranium in Well Water

If uranium is detected in your well water, several treatment options are available (not a sales pitch—just the facts):

Whole-House Filtration: Removes uranium at the point where water enters your home, protecting all taps and fixtures.
Reverse Osmosis (RO): Highly effective for removing uranium at a specific tap, usually for drinking and cooking water.
Ongoing Monitoring: Uranium levels can fluctuate, so regular testing (at least annually) is recommended.
Certified Systems: Look for systems certified by NSF International or the Water Quality Association for uranium removal.

No single solution fits every home—your choice may depend on water use, family needs, and budget.

Uranium in Well Water—FAQs

Q: How can I tell if uranium is in my water?

A: Uranium is invisible and tasteless. Only a certified laboratory test can detect it.

Q: Is uranium in water a problem for children or pets?

A: Yes. Young children and pets are especially sensitive to contaminants, making safe water essential.

Q: How often should I test for uranium?

A: Annual testing is recommended, or after major weather events or changes in your water’s taste or odor.

Q: Will a standard pitcher filter or boiling remove uranium?

A: No. Most pitcher filters and boiling are not effective. Only specialized treatment systems certified for uranium removal will work.

Q: What are the main treatment options?

A: Options include whole-house filtration, reverse osmosis for drinking water, and ongoing monitoring.

Q: Why does the EPA set the goal at zero if the legal limit is higher?

A: The legal limit (MCL) is based on what’s practical to achieve with current technology, but the health goal (MCLG) is zero because any uranium exposure carries some risk.

Q: Who can help me interpret my water test results?

A: A state-certified water professional or your local health department can help you understand your results and next steps.

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