Radiological contaminants in drinking water
Radiological contaminants are not added to drinking water by anything a treatment plant does. They are naturally radioactive elements that reach the water through erosion of the natural deposits the water passes through, which is EPA's own account of where they come from — so a system can carry them with nothing having gone wrong at the plant. 4 measures are covered here.
Two of the four are gross-alpha measures rather than a single element, and the difference is in their names: EPA's 15 pCi/L limit is written for gross alpha particle activity excluding radon and uranium (40 CFR 141.66), which is the second of the two.
The 4 in this group
Each page answers the same questions for its own contaminant: where it has been recorded, what the limit is, and what removes it — with the source for every answer.
Which limits are enforceable
Each of the 4 carries its own enforceable EPA limit — the maximum contaminant level (MCL) a public water system must meet. Every figure is on the contaminant's own page, with the unit it is set in.
What removes a contaminant, which certification covers it, and what boiling does to it are answered by name on each page above, with the source for each answer.
Where they come from
- Erosion of natural deposits of certain minerals that are radioactive and may emit a form of radiation known as alpha radiation
- Erosion of natural deposits
Collected from the source list each contaminant page publishes, where each line is attributed.
Is it in your water?
Each page above lists the water systems that reported a result above the health guideline for that contaminant. To start from a place instead of from a compound, look your system up directly.
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