The new New MEG (Maximum Exposure Guideline) for radon in water is 4,000 pCi/L. The State of Maine has established this as the level at which you might consider remediation. This new MEG should not be confused with the take action level of 10,000 pCi/L at which point remediation is strongly recommended. This can be confusing when home owners are trying to decide exactly what they should do. It can also contribute to the stress of buying or selling a home so for clarification we suggest contacting the Maine Radon Control Program office at 1-800-232-0842. As always we would be happy to answer any questions you have.

Radon in Water Options

There are two options for removing radon from your well water, one is an aeration system and the other is a GAC system (Granulated Activated Charcoal). Although there is a significant price difference between the two – the aeration system costing about twice as much as the GAC, most customers and radon contractors prefer the aeration system and here is why…


There are strict guidelines that must be followed when installing this system to avoid potential health hazards. Some of those health hazards include the likelihood of bacterial growth in the media, harmful gamma radiation, and possible low level nuclear waste. This system option is not something I would install in my home, so I choose not to offer it to my customers. Please read this for more detail GAC for Radon in Water


A much safer and easier way to remove radon from water is by aeration. Most of these systems will reduce the waterborne radon by 99%+. There are several different manufacturers of aeration systems, the most commonly used are the Bubble-Up series by Repco and the AIRader series. Bubble Up interactive brochure

Radon in water is easily removed. That is both a pro and a con. As stated above, nearly 99% of the radon in the water can be removed by using the aeration technique. The con is, every time the faucet is turned on, a shower is taken, or laundry is done, the water is being aerated. It is this process that strips radon from the water and then contributes radon to the air.