Back to Home Page RHMM
Previous Page



Radon may occur in well water or water from public sources (Community Water Supplies). As of this moment no regulations or guidelines are applicable, but there are indications that by the year 2004 the EPA will adopt guidelines for companies that deliver water to the public.
Currently there are two levels mentioned in this discussion:
For states that implement a multimedia mitigation (MMM) program (i.e. inform the public that radon can be caused by various sources: soil and water) the radon concentration level may be 4000 pCi/L (per liter of water). This is known as the Alternate Maximum Contamination Level (AMCL).
For states that do not implement a multimedia mitigation (MMM) program the level will probably be set at 300 pCi/L (per liter of water). This is known as the Maximum Contamination Level (MCL).

In comparing the guideline for the action level concentration of radon in air - 4 pCi/L (per liter of air) - with the action levels in water as indicated above there is a large difference because of the higher density of water than air. For example from previous scientific studies it was derived that on the average every 10,000 pCi/L per liter water in a home contributes approximately 1 pCi/L per liter of air to the indoor air environment.
For this reason it makes sense to test the well water in a home where high indoor air levels exist as part of the testing before mitigation of the indoor air environment starts. Nevertheless at the same time it makes sense to mitigate the indoor air quality based on soil-gas release first, because this contribution to the indoor air radon concentration is usually higher.

For example if a well in a house has 50,000 pCi/L per liter water and the radon concentration in air is measured to be 45 pCi/L per liter air, the contribution of the radon in water to the indoor air can be estimated to be 5 pCi/L. The usual soil type mitigations (ASD such as SSD or SMD) alone (even if done completely) will on the average not be able to bring the radon concentration in the indoor air in this house down to below 5 pCi/L. Here both types of mitigations would be necessary to reach the EPA indoor air Action Level of 4 pCi/L per liter air.

How Can I Perform a Radon-in-Well-water test myself?

Contact us via our phone number (970) 416-0196. After a deposit by mail or credit card is processed we can send you three test bottles with instructions how to properly extract water from your well. Send these bottles to us by express mail using enough packaging material around it and the analysis can be done within 24 hours after we get your sample. For fastest result we fax or e-mail the written report. The following photo shows the test emenation process that follows manufacturer's guidelines.

35f1 Test of water for concentration of Radon-222

We can also perform Radium-in-Well-water tests for you?

Contact us via our phone number (970) 416-0196. See photo below of two sample radium-226 tests.

36f1 Test of water for concentration of Radium-226

Back to Home Page RHMM
Previous Page