Maine Water Radon

If you have a home in Maine, you’ve most likely heard of or dealt with Radon at some point in your life.

In this issue we’ll offer our thoughts on the 2 available methods for removing Radon from your home’s water supply.

We’ll look at the pros and cons of each, so hopefully you’ll have a better idea as to which method is best for your family.

When to Treat for Maine Water Radon?

If you have a home that has tested above the recommended Maximum (4,000 pCi/L) for Radon in its water supply, both the the EPA and the State of Maine recommend mitigating your water for safety.

We won’t spend a lot of time in this article discussing the health risk factors associated with Maine water Radon. If you are reading this article we’ll assume you most likely already have concerns about the risks. We’ll also assume you’d like to know how to get rid of Radon so your family is safe.

How does Water Radon affect my Family?

Maine water Radon is a gas. When the Radon is underground, the gas can enter your water supply. The gas travels through the veins that feed your well. It’s then released back into your home’s air once it exits through points like shower heads (highest concern), dish washers (2nd highest concern) and washing machines (3rd highest).

When you directly breathe in Radon gas, especially at close proximity, this is when the concerns start.

How do I get rid of Radon from my Water?

I wish I could tell you that there are multiple options for removing Radon from your home.  But, unfortunately, that really isn’t the case.

At this point in time there are two feasible options for removing Radon from your water, based on the technology that’s currently available:

  1. Aeration Ventilation (bubble-up systems)
  2. Granulated Activated Carbon Adsorption (charcoal adsorption)

There are vast differences between the two methods of Radon mitigation. Each has their own pluses and minuses.

We’ll be very up front here by saying that as water treatment professionals; we deal solely in Bubble Ventilation for our clients.

We feel the upsides far outweigh the downsides in the vast majority of situations for most people. Units like the Repco Bubble-Up Radon System have proven extremely reliable over the years throughout thousands of homes in New England.

Having said that, there are occasional situations for a homeowner when a GAC system might be a viable option to look at.

Let’s take an objective look at those plusses and minuses for both methods, so that you can make your own decision as to which system might be right for you and your family.

1.        Bubble Up Aeration | What is it?

Do you remember when you were a kid and you used to blow bubbles down through a straw in your glass of Soda? Well, whether or not you knew it, you were actually practicing Bubble Up Ventilation.

Water Radon Ventilation systems do the same basic thing for your home.

Untreated well water passes into a Radon Bubbling System (before entering the rest of the home).

Once inside the system, a blower unit forces air down inside the tank. Gas bubbles then rise to the top of the water’s surface.

Once the bubbles reach the surface, a vent line captures the gas and then directs it to a point outside the home. In essence, the system simply “vent’s” the gas before it can be vented into the home through fixtures & appliances.

maine water radon bubble up

The remaining “treated” water is now safe to use and able to continue its journey throughout your home.

That’s really how these systems operate. Pretty simple in actuality, but extremely effective and reliable.



The Pros

  • 95-99% removal rate
  • Effective at extremely high concentrations of Radon (well into the tens of thousands of pCi/L)
  • Lower long-term costs
  • No removal or disposal of Radioactive material needed
  • No need to follow rigid State or EPA testing & removal schedules
  • Typically increases home’s water pressure and flow


The Cons

  • Higher up-front costs (typical systems averaging between $4500-$4900 installed)
  • Requires outside venting line
  • Requires electricity
  • Larger than GAC systems


2.       Granular Activated Carbon Adsorption (GAC) | What is it?

Carbon Adsorption, in its simplest form, is exactly like it sounds; it adsorbs Radon gas.

GAC systems use actual granules of charcoal to adsorb Radon gas from a home’s water supply, before it exits the shower heads and appliances that we talked about earlier.

An upright torpedo style filter tank is filled with GAC particles. The home’s main water supply runs through this filter tank and literally acts like a sponge to remove Radon contaminant from the water, before passing along to the rest of the home.

GAC tanks adsorb Radon gas until the charcoal granules are saturated and can no longer work properly. The tank(s) then require disposal and replacement.

The installing water treatment professional and the homeowner follow a program called Carbdose. This is a program structured by the State and EPA to monitor safe usage and insure proper timing for re-testing and tank replacement.


The Pros

  • Lower up-front cost (about half the cost of Bubbling systems)
  • Smaller than Bubbling Systems
  • Requires no electricity
  • Requires no venting

The Cons

  • 85-99% removal rate
  • Effective and safe only at lower Radon concentrations (5,000 pcI/l or less)
  • Higher long-term costs (requires continual tank replacements)
  • Requires adherence to State & EPA Carbdose program
  • Requires proper shielding of units
  • Requires “Radioactive Material” stickers on units  
  • Typically less appealing to prospective home buyers


The above information is a “nutshell” version of the 2 methods of Maine water Radon mitigation available today, and how these systems function. Hopefully this will give you a basic idea of each’s pros & cons as well as which might be a suitable option for your home and your family.

In future articles we’ll go into more depth on how these systems work.

For now, if you have any questions about these treatment methods, or if you have questions about Radon in general, feel free to contact us directly at (207) 675-3272.

You can also review more information about Radon in the following articles:

Radon 101 | Is my Water safe if it has Radon?  

DIY Water Radon Test | Maine Water