Earlier this month, researchers from Johns Hopkins University published a study in the journal Environmental Health Perspectives detailing the increase in radon concentrations in homes in the state of Pennsylvania since 2004, particularly in those near to fracking operations. This is a serious issue that deserves more attention. I will explain why after providing the nickel summary of fracking.
Many underground rock formations, shale formations in particular, contain natural gas that is trapped in small pockets. To retrieve it, gas companies drill vertically to the depth where the natural gas resides, then drill horizontally in multiple directions, and finally fracture the rock by pumping millions of gallons of a high-pressure mixture of water, sand, and toxic chemicals down into the rock formation.(1) After the rock has been fractured, approximately 60% of the water is withdrawn from the well, while the sand and some of the chemicals remain in the ground. After this water has been removed, the previously-trapped natural gas can flow horizontally to the vertical hole and then up to the surface for recovery.
The graphic below from Energy Tomorrow shows the general configuration of a fracking well. The vertical portion of the well crosses through an underground aquifer on its way downward. Underground aquifers are the water source for drinking water and agricultural irrigation wells. In order to try to prevent contamination of the aquifer with either fracking fluids or the components of natural gas, the vertical portion of the well that crosses the aquifer is encased with concentric layers of steel piping and concrete.
The cracks in the rock formation made by fracking, which can be as long as 500 feet, are shown above and below the horizontal portion of the well. In order to avoid opening a pathway for toxic fracking fluids to contaminate the aquifer, fracking operations should be performed at a depth which is at least 1,000 feet below the bottom of the nearest aquifer.(2) In this particular graphic, the vertical separation is shown as 6,000 feet, which is rather far removed from the aquifer. In practice, the separation is often much less than this. It should not surprise you to learn that Energy Tomorrow is a natural gas industry lobbying group.
Public concern about the health risks of fracking have focused primarily on the possibility that the toxic chemicals used in fracking will contaminate aquifers. As I discussed in Methane in the Water Part I: Toxicity, cases of this occurring, at least thus far, seem to be rare. What is quite common, particularly near the Marcellus Shale formation in Pennsylvania, is increased concentrations of methane – the primary component of natural gas – in the aquifers. A study published by researchers from Duke University concludes that methane is entering the local aquifers not through underground cracks formed in the fracking process but rather via leaks in the steel and concrete casing of the vertical portion of the well. While methane infiltration of the aquifers does present some fire and explosion risk(3), it is not toxic to humans.
OK, that may have been a bit more than the nickel summary, but the background is necessary to explore the radon-related problems of fracking. Radon is a radioactive gas which is produced during the natural decay of uranium and other radioactive elements. Therefore, areas of the country that have underground rock formations which contain radioactive elements also have radon. Homes in these areas tend to accumulate radon gas, particularly in basements and crawlspaces. Radon enters homes by diffusing through the ground and then through cracks in a home’s foundation, as a dissolved gas in the water supply, and as a minor component in the natural gas burned by the homeowner. Since radon is an inert gas, it will not be destroyed or impacted in any way by passing through the flame zone of any natural gas burners in the home. Therefore, all radon atoms in the natural gas supply to the home will escape into the indoor air.
Even without the impact of fracking operations, radon gas has long been a problem in Pennsylvania. According to the Department of Environmental Protection, approximately 40 percent of homes in Pennsylvania have radon levels that exceed recommended limits. This is an issue with which I have personal experience. In order to sell my home in Pennsylvania in 2000 to move to Chapel Hill, I had to apply sealant to the basement floor and walls, install a vapor barrier for the sump pump, and improve ventilation for our home to meet approved radon levels.
Radon exposure is a serious matter. Since it is a gas, you can breath this highly radioactive material directly into your lungs. As a consequence, radon exposure is the second leading cause of death by lung cancer in the United States, killing 21,000 people per year. While the key safety parameter is the amount you breathe in, radon limits for drinking water have been established as well. Radon dissolved in the water you drink is not considered to be particularly harmful. However, if radon is dissolved in your water, it will slowly evaporate into the surrounding air.
When natural gas is liberated from a rock formation, any other gases trapped in the formation will come along for the ride. The Marcellus Shale formation – the primary location for fracking in Pennsylvania – contains 20 times more radioactive material than a typical shale formation. Studies have shown that natural gas produced from fracking in the Marcellus Shale formation has 40 to 70 times more radon than the U.S. average.
Since we already know from the Duke study that methane from fracking wells is infiltrating drinking water aquifers in PA, we can be nearly certain that radon is as well. Once the concentration of radon increases in the local aquifers, its concentration will increase in nearby houses as well via the pathways I outlined above. With this knowledge in hand, we should not be surprised that the Hopkins study found “statistically significant correlations” between household radon concentrations with both the 2004 onset of fracking operations in PA and the distance between the house and the nearest fracking well.
On March 18th of this year, the permitting process for fracking began here in North Carolina. Despite having written about fracking and its potential risks many times, until now I overlooked the now-obvious potential radon exposure issues. Fortunately, those of us in the Tar Heel State are at less risk than my old friends in the Keystone state. According to the map on the NC Department of Health and Human Services website, the levels of radon in the counties being targeted for fracking are rather low. Therefore, our risk of radon exposure here, at least in the aggregate, is lower than in Pennsylvania. Nevertheless, there may be localized areas in which dangerous radon levels could be reached. As the NC Oil and Gas Commission reviews its regulations for fracking, this risk should be taken into consideration.
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1. For a more detailed background on fracking, please read To Frack or Not to Frack. For information on which chemicals are used in the fracking process, please read Fracking Gag Rule Part I: Trade Secret?
2. Please note that different states have adopted different regulations on the minimum vertical distance between fracking operations and aquifers. The recommendation of 1,000 feet, twice the length of the longest expected fracture, is based on my own engineering judgment and is more conservative than some state statutes.
3. For more details, please read Methane in the Water Part II: Fires and Explosions.
The odorless, colorless gas radon is the second leading cause of deadly lung cancer in the U.S. – and too often, it’s found in our homes.
January is National Radon Action Month.
The North Carolina Radon program has distributed approximately 7,000 free radon testing kits across the state, and Orange County only received about 30 of them.
“They are available on a first-come-first-serve basis, said Stacy Shelp, public information officer for the Orange County Health Department. “Anyone’s eligible. There’s no income requirement, etc. People just have to stop by the Environmental Health Dept. in Hillsborough, starting on the 12th of January, or give us a call.”
They’re available through January 30th, or while supplies last.
Thirty test kits aren’t a lot, obviously. But Shelp said there’s no need to panic.
“The good news is that Orange County is not particularly prone to radon,” said Shelp. “You typically find radon in places that, geographically, have high presence of granite-type bedrock. So, the North Carolina mountains, particularly, would be more concerned.
Still, she added, radon is not found more often in any particular kind of structure, so we should all take precautions against it.
Shelp said that once the supply of free kits runs out, the NC Radon Program will return to providing kits for $5.35, at a savings of nearly $10.
You can also buy a kit for around $15 at a big-box home improvement store, or just about any small hardware store.
The Orange County Environmental Health Department is located at 131 West Margaret Lane, Suite 100.
You can call the EHD at 919-245-2360.
For more information on radon and how you can lower your family’s risk of lung cancer, you can visit www.ncradon.org.http://chapelboro.com/news/safety/oc-health-dept-offers-limited-free-radon-test-kits-month/
CHAPEL HILL – Monday night, the Council Committee on Boards and Commissions in Chapel Hill held its first of five community input sessions.
Stemming from Chapel Hill 2020, the Council Committee on Boards and Commissions has arranged for five advisory boards to meet in order to further the Town’s development progress.
The first of these meetings hosted the Transportation and Connectivity Advisory Board.
The topics covered in four following community input sessions include community design, environmental stewardship, community housing, and planning.
The Council Committee on Boards and Commissions arranged these sessions in order to gain participation from community members.
These meetings will be conducted at 6:30 PM at the Chapel Hill Public Library, located at 100 Library Drive.
If you would like to attend a meeting, click here.
The Land Use Management Ordinance of Chapel Hill has instituted rules for political signs to prepare for the upcoming municipal and school board elections in November.
Temporary political signs promoting candidates or topics are permitted, as long as they are at most four square feet in area.
Political signs erected on private land must be taken down seven days after the election has ended.
Signs located in the public right-of-way may be assembled up to 45 days before the election and must be taken down within 12 days after the election.
Signs may not block the traffic signals or road signs. In addition, signs may not use terms or images that could confuse drivers with directional or regulatory traffic signs.
Many families are not aware that they may be at risk of lung cancer, due to inhaling radon gas.
Radon gas comes from the decay of Uranium in soil and can sneak into homes by air movement through soil, cracks in foundation, well water, and some building materials, like concrete.
Radon stands as the chief source of radiation for Americans. Also, radon can attack sensitive tissues in the lungs, resulting in cancer.
Using Radon Resistant New Construction, home builders can construct new homes to prevent radon intrusion.
The North Carolina Radon Program is providing a limited number of free radon test kits, specially for NC families with newborns. Also, test kits can be bought at hardware stores and the N.C. Department of Health and Human Service’s website.http://chapelboro.com/news/news-around-time/community-input-sessions-for-chapel-hill-development-process-political-sign-regulations-radon-prevention/