Environmentalists point to various dangerous consequences of using fracking technology, but none can be compared to the issue of radiation exposure and radioactive contamination of the development areas it poses.
Deep down in the earth, there is a lot of radioactivity, which is safe enough, so long as it is not brought up to the surface. The technical term is NORM (Naturally Occurring Radioactive Material). When it is brought to the surface it becomes Technologically Enhanced, or TENORM, and it is a serious health problem near oil wells and gas production sites. It is in the production water, in the oil, in the gas, around the production sites, the groundwater, in the pipes and tanks – and in your kitchen.
The shale strata are between 1,000 and 8,000 feet deep. Owing the weight of rock above, the pressure on the rocks in the gas bearing strata at these depths is enormous. The drill has to pass a tube (the “gun”) along the stratum for as long a length as possible and then this has to become perforated along its length with holes that allow the gas or oil to get into the tube and up to the surface.
Historically difficult. But technology has come to the rescue in the manifestation of specially designed explosives called “shaped charges.” These are cone-shaped dense metal explosive devices that send the explosive energy in an enormously powerful directed jet of metal atoms that act as a drill and melt the rock or shale along the length of the jet. This creates a radially distributed set of channels along and around the length of the drill tube, in the shape of a bottle-cleaning brush. Once this is done, water containing a whole range of acids and chemical additives is injected under immense pressure and this is followed up by small balls and sand or grit, termed “proppant” like the pit props in a mine, to hold the channels formed open. The extreme pressure pushes the weight of the upper layers of rock upwards and releases the tension in the strata where the gas is trapped. It has been noticed that the effect of all this on geophysical stability of the local deep earth results in small earth tremors and shocks, noticed by people living nearby. But the real cause of these tremors may be more sinister.
The metal which was formerly employed for the shaped charge head or “gun” was copper. This creates a pressure of 300,000 atmospheres which pushes the rock aside by plastic deformation. But in 1984 a US patent (US 4441428) was filed by one Thomas Wilson, entitled “Conical Shaped Charge Liner of Depleted Uranium.” The patent begins: “this invention relates to a novel blasting device especially adapted for drilling oil and gas wells.” Wilson records that DU is 5-times as efficient as copper in terms of the length of the jetted hole, creating a pressure of 600,000 atmospheres. Because of the uranium’s greater chemical reactivity it actually creates new chemical compounds with the material in the rock (and the oil and gas).
Radon has a half-life of about four days, and so if the gas takes a short time to get from the well production site to the consumer, then levels in the kitchen can be significant. He calculated that there would be between 1,000 and 30,000 extra lung cancers in New York State from such an exposure. And that no one in environmental protection agencies had paid any attention to this issue.
This is certainly of concern, but there are other issues. The process water (and chemicals) certainly contaminates the areas around the gas production machinery. In a recent court case I was involved with in Louisiana there was a gas distribution plant that was scarily radioactive, and the land around it was also radioactive. I also studied oil well production areas in a Kentucky court case. The process water dissolves Radium-226 and this precipitates as scale on the pipes and tanks and is left on the ground near the wellheads and distribution facilities. The transfer pipes are radioactive. One of the worst radionuclides left behind is the Radon daughter Lead-210 which has a longish half-life (22 years) and builds up in these situations as a fine dust. It gets into the gas stream as nanoparticles and I believe it remains in the gas stream. It decays to Bismuth-210 which immediately decays to the alpha emitter Polonium-210 with a half-life of 138 days.
Fracking will increase the amount of Radon in the extracted gas. Why? Because of the high surface area created by smashing up the rock. In the simple gas or oil well there is a big cavern. The radon seeps out of the wall which has a surface area equal to that of the cavern wall. But in the case of the fracked strata, the surface area out of which the Radon can seep is enormously enhanced. So a faster Radon transfer can occur.