If you draw your drinking and bathing water from a private well in or around St. Charles, radium is one contaminant worth asking about by name. Radium is a naturally occurring radioactive element that can move into groundwater from rock and soil. Standard home kits and basic hardness checks do not reveal it, so the test has to be requested on purpose.
Why radium gets its own line on the list
Most private well tests in the area focus on bacteria, nitrate, and hardness, which are the common concerns for homeowners. Radium and uranium are different. They occur naturally in some geology, and levels can vary from one well to the next, even on the same street. Many nearby wells tap the Missouri River alluvial aquifer, which is a mix of river influence and local rock, so a neighbor's result may not describe your well.
Homeowners near the documented Weldon Spring site often ask about radium first. Local context treats naturally occurring radium and uranium as a more relevant concern in that part of St. Charles County. A well in that vicinity is a reasonable reason to request a lab test instead of relying on a general screen. Being near a known site does not mean your water is affected, and being farther away does not rule it out.
What a useful radium test looks like
Radium testing is a laboratory job. Ask a state-certified laboratory for a radium test in drinking water, and confirm whether they report the two main radium isotopes separately or together. If uranium is also a concern, ask for it in the same order so you do not need a second sampling visit.
- Request a sample bottle from the laboratory and follow its collection instructions exactly.
- Collect from a cold tap that has not passed through a softener, filter, or treatment unit, unless you specifically want to test the treated output.
- Record the date, the time, and whether the water had been sitting in the pipes overnight.
- Ask how long results take and whether the laboratory will send them to you directly.
Reading the result without guessing
A laboratory report lists the measured amount for each isotope along with a reporting limit. Read the units on the report and compare the result against the drinking water standard the laboratory cites, not a number you saw online. Keep in mind that one sample is a snapshot. If the result is higher than you expected, contact your state drinking water program or a qualified professional about a confirmation sample and the next steps. A home test strip or a neighbor's experience is not a substitute for a laboratory result.
If the result comes back high
A high result is a reason to act, not to panic. Start by confirming it with a second sample collected the same way. Then look at the source. Radium levels can be tied to the aquifer and to the well's depth and construction, so the answer may involve the well itself, not only the water coming from the faucet. A licensed well contractor or your local health authority can explain which steps fit your property. Avoid buying treatment equipment before you know exactly what you are treating.
Keep the test on your calendar
A laboratory test is a point-in-time result, so it helps to retest after major well work, after flooding, or when ownership changes. Keep every report in one folder with the date, the well location, and the sampling method noted. A clear record makes it much easier to see whether anything has changed over time.