Evidence of Fracking Risks Grow in Texas and Other States, Scientists and the government do not yet know the full extent of the hazards of hydro fracking, but increasing evidence suggests that fracking is not as safe as was once thought

Evidence of Fracking Risks Grow in Texas and Other States, Scientists and the government do not yet know the full extent of the hazards of hydro fracking, but increasing evidence suggests that fracking is not as safe as was once thought Press Release by OIl and Gas Injury Lawyers, August 24, 2012, Ditgital Journal
The testing of water wells and aquifers near Pennsylvania’s Marcellus Shale showed that the naturally occurring brine had likely migrated upward, contradicting the belief that the layers of rock will always seal in material that is injected through drilling. The oil and gas industry and a scientist who is a member of the National Academy of Science’s peer review panel have criticized this study, noting that it cannot be determined that the salty fluids actually came from the Marcellus shale, what path the fluids took or the exact length of time that passed. The scientist did not, however, dispute the finding that the brine did move upward — implying that fracking fluids could as well. Months earlier, a separate study predicted that contaminants from fracking could reach the surface within 100 years. And last year a study found that methane gas was more likely to contaminate water supplies in locations adjacent to drilling. In Wyoming, the EPA has concluded that contamination of groundwater in central Wyoming was linked to fracking. Residents had complained that their well water turned brown after gas wells were fracked nearby. In 2008, the samples from the water wells showed hydrocarbons and traces of contaminants that could be related to fracking. The EPA cautioned residents not to drink the water and to ventilate their homes when they bathed because methane in the water could cause an explosion. The EPA later found that pollution from abandoned oil and gas waste pits were responsible for some groundwater pollution, but contamination in two deep test wells had to have been caused by fracking. Increasingly, it appears that the evidence continues to point to a wide range of potential hazards for people who work and live near wells.
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Earlier this year, federal workplace regulators issued a hazard alert because workers may be exposed to dust with high levels of silica during the fracking process. Silica can cause a disease called silicosis. When breathed in, silica can cause inflammation and scarring, reducing the lungs’ ability to take in oxygen. A chemical safety expert says that at a high enough level, even short term exposure can cause long-term damage. In one air sample taken for the study, silica levels were more than 10 times the safe limit.
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Medical groups and government agencies are beginning to raise concerns about the potential for oil drilling, including the fracking process, to damage the health of residents and workers. The extent and cause of health problems, however, is not yet known, because state and federal governments have not comprehensively examined how drilling affects human health. As worries about the potential health and environmental hazards of fracking grow, governments and residents in areas where fracking is used extensively are increasingly vocal about their opposition to the process.