Engineering ingenuity is unlocking a vast storehouse of natural gas buried beneath American soil from Texas to New England. The sudden great promise of clean, homegrown shale gas has all kinds of people excited. National-security types see it as a replacement for foreign oil and gas, environmentalists as a replacement for dirty coal and even oil. And because it yields only 45% of the carbon dioxide emissions of coal, advocates of taming global warming see it as a temporary crutch while carbon-free energy sources are developed and deployed. Everyone seems to agree with a March study by IHS Cambridge Energy Research Associates that concluded that shale gas "provides the potential to transform North America's energy landscape." The problem is that word "potential." Every link in the chain between the newly abundant domestic energy source and its transformative impact is still shrouded in uncertainty. And a rising tide of NUMBY—not under my backyard—that's greeting shale gas in the Northeast could hobble the revolution (see sidebar).
Full story at http://www.sciencemag.org/cgi/content/full/328/5986/1624?sa_campaign=Email/sntw/25-June-2010/10.1126/science.328.5986.1624
Now that drillers have figured out how to extract gas trapped in shale rock (see main text), a new and perhaps more hazardous style of drilling is coming to parts of the country unfamiliar with the ways of the oil and gas industry. To those outside the industry, the scariest part of the new drilling might be the way drillers unleash the gas. They drill straight down, turn the drill to go horizontally, and then pump in chemically treated water to pressurize a horizontal section of the well until surrounding rock fractures and begins to give up its gas. Many local residents and environmentalists have worried that this "fracing" (pronounced and sometimes written "fracking") might propagate fractures upward into overlying aquifers so that escaping gas, chemicals, and brine will contaminate groundwater.
Full story at http://www.sciencemag.org/cgi/content/full/328/5986/1625?sa_campaign=Email/sntw/25-June-2010/10.1126/science.328.5986.1625