Fleck Radon in Water Filter

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What Certified Laboratory Testing Reports About Radon and How to Interpret Results

Certified laboratory testing for radon in water measures the concentration of radon-222, a radioactive gas naturally found in some groundwater sources. Test results are typically reported in picocuries per liter (pCi/L). For household water, a certified lab report tells you the radon level specific to your sample but does not automatically categorize the water as unsafe or requiring treatment. The U.S. Environmental Protection Agency offers guidance levels for radon in water; however, it is important to understand that a detection or a level below these guidelines does not mean a health hazard or violation.

Influence of Sample Depth, Well Depth, and Source Type on Expected Radon Levels

The depth of a well or sampling point can affect radon concentration because radon originates from the decay of uranium in soil and rock. In Anne Arundel County’s aquifer 217PPSCU, government samples came from wells between 200 and 439 feet deep. Typically, deeper wells may show different radon levels than shallow wells due to varying geology and radon generation. Sample type also matters; groundwater from private wells can differ in radon concentration compared to municipal sources that blend or treat their water.

Comparing Radon Data from Anne Arundel County with Neighboring Areas Without Overinterpretation

Anne Arundel County’s groundwater radon data reports a median of 57.0 pCi/L with a range from 29.0 to 124.0 pCi/L, based on three wells sampled over several years. When comparing this with nearby counties, it is important to avoid assuming your specific well matches these values. Regional data show what has been detected historically in the aquifer area, but actual conditions vary widely. Area medians provide context but are not definitive for any household’s water.

Pathways for Radon Entry into Groundwater in Anne Arundel County

Radon-222 in groundwater results from the natural radioactive decay of uranium present in underground rock formations. In Anne Arundel County’s aquifer 217PPSCU, radon enters groundwater through contact with radium and uranium in the local geology. Once dissolved, radon gas can accumulate in water sources, especially in deep wells that tap into confined aquifers. Radon found in water can then potentially transfer to indoor air during water use, which is a consideration for household exposure.

Differences Between Public Water System Records and Private Well Testing in Establishing Radon Levels

Public water systems in Anne Arundel County regularly test for radon and publicly report results. These systems often blend water from multiple sources and may apply treatment, resulting in radon levels that reflect the system overall rather than specific well concentrations. Private household wells do not benefit from such blending or treatment unless the homeowner takes action, making private testing essential to know individual water conditions. Area sampling data give a regional overview but cannot substitute for a household’s own water test.

What Area Radon Data Should Not Lead You to Conclude

Government sampling data from Anne Arundel County’s aquifer provide a general picture of radon-222 presence but do not specify the radon level in your well or household water. Detection across sampled wells is not a violation or indication of unsafe water by federal thresholds. You should not assume your water’s radon level is at the median or within the sampled range without individual testing. To address radon in your water effectively, consider obtaining a certified laboratory test of your household water. For proven mitigation, the Fleck Radon in Water Filter ships ready to configure for residential water systems, reducing radon concentrations documented in similar water sources.

Where this information comes from

Source: USGS groundwater sampling. Sampled 2016-11-30. These figures describe groundwater sampled in this area. They are not a test of any individual private well - only a test of that well can establish its own water.

On record: U.S. Geological Survey sampling of Radon-222 in the 217PPSCU aquifer (Anne Arundel County): 3 results from 3 wells, median 57.0 pCi/L, range 29.0-124.0 pCi/L; none above any federal threshold