Saturday, December 1, 2012

Radon in Natural Gas from Marcellus Shale

Radon is a radioactive gas that is produced whenever gas is extracted. It travels with the gas through pipelines to the point of use. Radon has always been present in natural gas, and is currently present in the NYC gas supply. Prior to the use of high-volume, slick water, hydraulic fracturing (fracking), the gas coming to New York City was supplied from areas in Texas, Louisiana and the Southwest, or as the map above indicates (in blue), from areas of low radioactivity and at great distance.
Radon has a half life of 3.8 days. Using the general rule of thumb of 10 half lives to decay to 1/1000 of original concentration, that would be 38 days, or roughly one month, depending on how radioactive it was to start. With radon gas, the minimum dangerous concentration is much lower if breathed in. Twenty half lives (or 1/1,000,000 of original concentration) would require 76 days or two and a half months. When fully decayed, radon converts to polonium and lead, also dangerous substances.

In the old days, much of our gas supply came from from “conventional” sources, i.e., as the by-product of oil extraction, or via simpler vertical drilling or vertical low-volume fracking. The problem is that conventional gas supplies are running out. It is now estimated that 80-90% of our overall gas supply is fracked; both Mayor Bloomberg and former Chesapeake Energy CEO Aubrey McClendon have stated that “all” gas is fracked now.

As shown on the map above (in pink) The Marcellus shale play is particularly high in radioactivity; by some estimates as much as 70 times more radioactive than average. Following the development of the fracking, the gas supply to New York City is changing. as more and more of our gas supply will be coming from this area. The proposed Spectra pipeline has been leased to Chesapeake Energy, one of the prime Marcellus drillers.

The fact that this source is much physically closer to New York also means that the radon has less time to decay in transit, a matter of hours from drill sites in Pennsylvania. It follows that radon levels in city apartments will therefore be higher as the proportion of Marcellus gas in our supply increases. During winter months, when demand is higher, gas is delivered faster, and, with apartment windows tending to be closed, the risk would be even greater.

Of particular concern is the typical New York City kitchen, which tends to be small, poorly ventilated, and usually without a window or hood vented to the outside. New York City building codes now prohibit external vents for cooking odors, and most apartments have only a recirculating hood or a passive wall vent. Passive vents are connected to other apartments and release to the roof of the building. In many homes, that vent is often sealed to block neighbor’s cooking odors, exacerbating the problem of poor ventilation.

Although–like asbestos–when inhaled, there is no safe amount of radon, the EPA has set a measure of 4 picocuries per liter (pCi/L) as the “actionable” level inside a home. The majority of readings from a recent citywide baseline test of the gas supply in NYC kitchens, conducted by Sane Energy Project, ranged from .3 to 2.6 pCi/L. At the moment, our radon levels are below actionable, and we want to keep it that way.

The Spectra pipeline, and other planned pipelines, could increase the risk that NYC residents will inhale radon when they cook with their gas stoves, do laundry with their gas dryers, or maintain their gas boilers. Radon is the second leading cause of lung cancer after smoking, and the increased exposure could potentially cause an additional 30,000 lung cancer deaths.
Radon is even more of a danger to children and pets, because it “sinks,” meaning it is heavy (it decays to lead) and seeks the lowest level of the space it occupies. Combined with studies that link gas cooking emissions with lowered infant development, this is truly cause for alarm. The draft EIS (Environmental Impact Statement) of the Spectra pipeline does not include radon in its review of issues. This is a subject which deserves further study before this, or any other supplies of Marcellus gas, are delivered to the residents of the five boroughs, where it may endanger the health of tens of thousands of citizens.

In addition to the inhalation risk, radon and its source, radium, create other problems with pipelines: As the gas travels, decay causes radioactive elements (the so-called, “daughters of radon”) to plate out on the sides of the pipelines, eventually creating radioactive “hot pipes.” Replacement, disposal, and cross-contamination with nearby water pipes and utilities could be yet another result of the use of high-radon fracked gas.


Map: US Geological Survey
Chart: Comparative danger of radon

Radon in Natural Gas from Marcellus Shale By Marvin Resnikoff, Radioactive Waste Management Associates

Sierra Club filing regarding Radon Study by Dr. Resnikoff

Sierra Club Atlantic Chapter press release quoting Professor James W. Ring, Professor Emeritus of Nuclear Physics at Hamilton College

Gas Emissions can Stifle Infant Development, Environmental Health News

EPA guide to Radon


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