How to Remove Radon From Well Water

Well Water Radon Removal

How to Remove Radon From Well Water Nobody likes the idea of radioactive gasses seeping into their home. Fortunately, while radon can be quite dangerous and is surprisingly common, there are several ways to protect you and your loved ones from this naturally occurring hazard. The health risks presented by radon make it worthwhile to educate yourself about what radon is, how you detect it in your well water and the mitigation options available to protect your home.

After being in the real estate business for the past twenty eight years, I have come to realize that most people have no idea that radon can be found in well water. This becomes readily apparent when working with clients who are either buying or selling a home.

When meeting with a seller I always inform them of the most common inspections a buyer will have when purchasing a home. If the seller has a well, a large percentage of the time the buyer will have the well tested for both quality and quantity. Most of the time however, the standard quality testing for well water does not include scanning for radon. This is something you have to specifically ask to get tested.

A good buyers agent will recommend their client do this as part of the home inspection process. When selling a home it is a good idea to be prepared for the buyers home inspection. If the home inspection reveals the presence of radon in the well water it is generally accepted that the seller will address this issue. In real estate however nothing is cast in stone. You could find yourself in a transaction where the seller is a stubborn coot and doesn’t agree to mitigate the issue. If this is the case you are going to need to understand how to remove radon from well water. It is not all that difficult just not that cheap to remedy! First you will need to know what radon is and what it can do to you.

What is Radon?

Radon is a gas created by the breakdown of uranium. Many people are surprised to discover just how prevalent uranium is. It can be found in the water, rocks and soil surrounding many homes in the United States. How much uranium is present and how much radon is produced will vary widely from place to place. Often times I will hear my clients make statements like “my neighbors sold their home and did not find any radon so I know I don’t have any either. This statement is 100 percent false! First of all everyone has radon in their homes. It is just a question of how much and if you fall under what the EPA considers passable for health purposes.

It is important to understand that just because your neighbor has a passing radon level does not mean you will have the same results. Radon is found in pockets. The gas could easily be more prevalent in your home even though your neighbors have passed. Radon is not something you should take lightly. The buyer certainly won’t! In fact radon is one of the top home inspection problems to avoid. If you are going to be selling your home and have never tested either the air or water, it wouldn’t be a bad idea. Some buyers will pass on a home where radon is discovered even if you agree to rectify the problem.

A few years ago I was selling a home in Upton Massachusetts and the seller remembered that he may have had a failing radon test when he purchased his home years prior. My advice was to see if he could find the records from when he bought to see exactly what the level came in at. If it was close to the 4.0 pCi/L  requirement I would have just suggested to see what happens when the buyer does their test, as levels can fluctuate over time. If however, the test was significantly over the requirement one would assume it would fail again.

What Are The Health Risks of Radon Exposure?

Radon Health Risks According to the Environmental Protection Agency, or EPA, radon causes thousands of deaths every year in the U.S. The gas is radioactive, but it has no smell or taste, making it essentially invisible to our senses. If the concentrations in the air are high enough radon will cause lung cancer. The EPA says that the only thing responsible for more lung cancer deaths than radon is cigarette smoke. Of course, if you smoke and are breathing in radon, your risk of developing lung cancer becomes much higher.

Well water in particular can become contaminated with radon. The EPA indicates that about 168 people die each year from cancer caused by drinking water containing radon. The majority of these deaths – 89% – occur from lung cancer as the radon is released into the air from the well water. The other 11% of deaths occur from stomach cancer related to ingesting the water.

Most scientists and those in public health agencies believe that health risks from direct consumption of well water are generally of minor significance. The day to day breathing of air is what provides the greatest exposure to radioactivity. There is a constant exposure when breathing air vs infrequent ingestion of drinking water.

The risk of dying from lung cancer as a result of airborne radon is estimated to be 1-2% for each 4 pCi/L of lifetime exposure. For drinking water, it is estimated that there is an additional lifetime risk of dying from cancer (mostly stomach cancer) of 1-2% per 20 to 40 thousand pCi/L in the water, depending on house size and ventilation.

These radon risk estimates however should be viewed with some caution. The estimates are based on assumed projections of high-level radiation risks to low-level risks. In the case of radon in the air, the lifetime exposure assumes 60 years and 100 years exposure in a closed home. The reality, however is that people spend time outside or away from their homes. Additionally, radon exposure is reduced when windows are opened in the summer or in bedrooms during sleeping hours.

It should be noted that failing radon levels are far more prevalent in air than in water when it comes to our homes.

How Do You Test For Radon in Well Water?

We are lucky to live in a time when the dangers of radon exposure in the home are well-understood. This means that testing your well water is easy to do and usually inexpensive – even free in some areas. The EPA actually recommends that people using wells for their water perform a radon test on the water. There is a Safe Drinking Water Hotline – 1-800-426-4791 – where you can find the phone number for your state’s laboratory certification office. This office will usually have contact information for laboratories that can test your well water for radon.

Keep in mind that you should follow all the instructions provided by the laboratory for the collection of the well water. You want to make sure that the test sample you send them is properly gathered and arrives intact to the testing facility. In Massachusetts, most home inspectors will provide well quality testing as part of their services. They will take a sample of the water for you and send it off to a lab for analysis. The testing generally takes around ten days to complete from the time it is received by the lab.

Do keep in mind however, that the standard battery of tests performed during a Massachusetts well test does not include radon. You need to specifically ask for your inspection to include this as a separate screening! Over the years, I have seen numerous real estate agents representing buyers, miss this aspect of the sale. Whenever there is a well it makes sense to test for the presence of radon. This will be one of the costs buyers have in purchasing a home. There is nothing more important than your health so it is worth checking.

How Do You Remove Radon From Your Well Water?

Radon Removal Methods Although there are devices that can remove radon from your well water at the tap, these are not the recommended method of radon mitigation. The best way to tackle the problem is by removing the radon before the water ever makes its way into your home. This way all water sources in the house are free of radon, not just the ones you happen to filter.

There are two main types of radon removal methods for well water:

Granular activated carbon – This filter installs outside of your home and uses activated carbon to remove the radon from the water. It is capable of removing around 95% of the radon in the water, making the water safe enough to use in your home. Granular activated carbon systems have several advantages – they are usually inexpensive to install and maintain, and are not prone to breakage due to the simplicity of the device. However, there are some long-term challenges when using this type of system.

The longer the filter is in place the more radioactive material is collected, meaning that disposing of the used filter may require special equipment and professional assistance. When enough radioactive particles are present the filter itself can be considered dangerous. The approximate cost of removing radon in water via the granular activated carbon method is about $1000-$2000.

Aeration – Because radon is a gas, it is possible to remove it from the water by simply blowing air through the water and pushing the resulting vapor out away from the home – typically through a pipe on the roof. Usually these aeration systems work by having an air source at the bottom of a water storage tank. The air source pushes air up through eh tank and on through a vent pipe. There are even units available that utilize air when filling the tank as well.

With both the bottom air ventilation and the filling aeration, it is possible to remove up to 99% of the radon from the well water. An aeration system will typically cost more when you purchase it and install it, but the long-term costs of owning it may be less because you will not need any sort of specialized disposal to get rid of radioactive filters.

It is recommended that you test your water periodically after you install the radon removal system. You will want to verify that it is working as it should. The typical cost of removing radon from well water with an aeration system is approximately $3000-$6000.

Several Benefits of Radon Filtration

The health benefits of removing radon from your well water are obvious. The money you spend on a filtration system is not just beneficial for your health, though. If you ever decide to sell your home you can expect buyers to question your home’s radon exposure.

The fact that you have addressed the problem beforehand will make your home more appealing to buyers and therefore easier to sell for a good price. There are very few buyers who will be willing to accept failing levels of radon in water. It makes sense you will want to address this issue not only for your families benefit but for the ease in which you will sell your home.

Additional Helpful Articles About Removing Radon From Well Water

Use these additional resources to make smart decisions when purchasing a home. There is nothing more important than being well informed when purchasing a home. If you happen to find radon in the water of the home you love don’t panic, as it can be corrected!


About the Author: The above Real Estate information on how to remove radon from well water was provided by Bill Gassett, a Nationally recognized leader in his field. Bill can be reached via email at [email protected] or by phone at 508-625-0191. Bill has helped people move in and out of many Metrowest towns for the last 28+ Years.

Thinking of selling your home? I have a passion for Real Estate and love to share my marketing expertise!

I service Real Estate sales in the following Metrowest MA towns: Ashland, Bellingham, Douglas, Framingham, Franklin, Grafton, Holliston, Hopkinton, Hopedale, Medway, Mendon, Milford, Millbury, Millville, Northborough, Northbridge, Shrewsbury, Southborough, Sutton, Wayland, Westborough, Whitinsville, Worcester, Upton and Uxbridge MA.

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  1. Alex Jennings says

    I had no clue what radon was until I read this article. Do you think I should hire someone to see if there is radon in my water? Is radon amounts regulated by the city?

  2. says

    This is great info about radon in well water. I think that it is a common misconception that you can assume you are safe if your neighbors are. The fact that radon can be found in small pockets is frightening. I remember hearing on the local news about a family that had radon poisoning. I had little to no reaction because I didn’t know what it was at the time. This is a great reminder.

  3. says

    Great article on radon in your home Bill! I’m a home inspector in Michigan and your exactly correct about Realtors not informing their clients about the dangers of radon in their water.

  4. says

    Good afternoon Bill. I have a home in Conway, NH that I am purchasing and the Radon water test came back as a fail. The level on the test were 15700 +- 300. The home already has radon gas mitigation. The NH acceptable level is <10,000. Is that the level for most states? The information on websites I have visited referenced on the GSA website that processed the test for me seem to be outdated with much of the information dating back prior to 2000. Are there any updates pending that you are aware of and do you have any additional recommendation for me?

    Regards, Susan

    • says

      Hi Susan – the passing radon level for water does vary from state to state. Here in Massachusetts the passing level is also 10,000 or less. Getting rid of radon is water is much more expensive than air. Plan on spending around $5000 to get a radon mitigation system.

  5. says

    Great article! I have been a home inspector since 2014 and also perform radon testing. It amazes me how uninformed people are about the reality of radon’s dangers. Thank you for writing this!

  6. Jan says

    I did a radon test and I was at 4.2. The EPA says I need to have remediation. Is there anything small I can do in my house like run the fan more to get rid of the radon

    • says

      Jan you are referring to radon in the air. You could seal any cracks you find in the basement floor. This might bring the radon levels under the action level of 4.0. Keep in mind you still will have radon in your home. The only way to bring the radon levels down substantially is to get a radon mitigation system. You should check for radon in your water as well.

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