|States such as Ohio face high unemployment, so residents often welcome gas extraction [GALLO/GETTY]
A new technique to extract lucrative hard-to-reach natural gas is causing earthquakes across Middle America, literally.
Hydraulic fracking - pounding streams of high pressure water and chemicals into rock formations to loosen gas deposits - has been hailed as a solution to the US's dependence on foreign petroleum. But residents of Ohio and other states worry the technology is moving the earth beneath them.
Susie Beiersdorfer was sitting in a deli in Youngstown, Ohio, on New Year's Eve, when she felt the 4.0 magnitude quake which made headlines across the US. "It felt like a truck hitting the side of a building," Beiersdorfer, a geologist who used to work in the energy industry, told Al Jazeera.
While this quake was one of the biggest to be linked to fracking and disposal of waste water from the process, it would not be the last. "They [state authorities] just released information on another quake that happened on January 13," she said.
In early January, the state government - which is responsible for regulating the industry - ordered the shutdown of five wells near Youngstown, after quakes rocked the area.
At least 11 earthquakes have been recorded around Ohio since March, causing controversy for the 177 deep well injection sites in the state which are being pumped full of nearly 37,000 barrels of toxic waste water daily.
"In the case of Youngstown, if we had reacted at the time of the first earthquakes, this well could have been stopped nine months earlier," John Armbruster, a professor of geology at Columbia University who has studied fracking, told Al Jazeera. "The earthquakes were there to provide a warning: Stop injecting."
By altering underground rock formations, fracking can expedite and accentuate earthquakes which - under normal circumstances would happen in the next 100 or thousand years, he said. "There should be a long-term concern about earthquakes that can result in a situation like this."
A spokesman for D&L energy, the company which allegedly caused the problem by sending waste-water deep underground, told reporters there is no proof his company caused the quake.
"It is in the best interest of the community to allow the research process to play out," Vince Bevacqua, a company spokesman, told a press conference in mid-January. "The well that people are concerned about - rightly or wrongly - is offline and will stay offline until we have answers."
Kate Sinding, an attorney with Natural Resources Defence Council, said environmentalists are "concerned these seismic events could be exacerbating cracks and fissures which can serve as pathways for toxic waste water - really nasty stuff - which could migrate over time to impact drinking water."
A study from The Proceedings of the National Academy of Sciences, published in May 2011, found that water samples taken closes to gas wells had on average 17 times more contaminants than normal.
In some cases, particularly in Western Canada, residents living close to gas installations have been able to light their tap water on fire because of contamination.
A draft study of drinking water in Wyoming, released by the US Environmental Protection Agency (EPA) in August, found clear links between fracking and water pollution.
"The way these earthquakes are trending is towards the northwest, where our source of drinking water is located," said Beiersdorfer, who has lived in Ohio for the past 18-years. "They [companies] are using two to eight millions gallons (seven to thirty million liters) for each well. There are documented fish-kills in our streams."
Larry Douglas Brown, a geologist at Cornell University, believes earthquakes linked to waste water are "a fairly rare occurrence" and that "risks have been magnified by a politicised environment".
Some water contaminates linked to extraction including "radioactive elements" and other "noxious stuff" have, however, "raised special concern", Brown told Al Jazeera.
View No fracking around: Protests against unconventional gas extraction in a larger map
Similar seismic events have hit the UK, where government regulators have been accused of "appalling complacency" by opposition politicians after earthquakes linked to fracking shook the city of Blackpool.
In the US, public opinion is mixed in the battle between job creation through energy exploitation and environmental protection.
Seventy-two per cent of Ohio voters want to see fracking stopped until more studies are done on its environmental and geological impacts, according to a Quinnipiac University poll released on January 19. However, 64 per cent of voters think drilling should continue despite possible harms.
"We really don't know what this technology means for the environment over the long-term," Sinding, the lawyer, told Al Jazeera. “Our primary concern is that the rush to develop these unconventional supplies is resulting in real health and environmental impacts because of a lack of appropriate safeguards at the state and federal level.”
People living near unconventional gas facilities have complained of skin rashes, headaches, neurological damage and other ailments, but data does not exist to conclusively link this anecdotal evidence to gas extraction.
A thorough study of the problem could cost upwards of $100m, officials from the US Agency for Toxic Substances and Disease Registry told Abrahm Lustgarten, a reporter with the investigative site ProPublica who has covered the issue extensively.
While thorough data on the long-term effects on fracking does not exist, policymakers and energy companies are moving full steam ahead to increase extraction.
Natural gas, much of it unconventional and requiring hydraulic fracking "has the potential, at least, to cause a paradigm shift in fuelling North America's energy future", Cambridge Energy Research Associates, a consultancy, noted in a 2010 report.
Are we entering a Golden Age of Gas? wonders a special report from the International Energy Agency from 2011. The US alone possesses 2,074 trillion cubic feet of gas, according to numbers cited by America's Natural Gas Alliance, an industry lobby group.
"The combination of two technologies - horizontal drilling and hydraulic fracturing - made it possible to produce shale gas economically, and from 2006 to 2010 US shale gas production grew by an average of 48 per cent per year," the US Energy Information Administration noted in its 2011 Annual Energy Outlook.
Opposition to the process has, however, intensified along with extraction, even in economically troubled regions such as Ohio, which has seen its manufacturing base hammered by outsourcing and foreign competition in recent years.
"This shale [gas] boom does not have a safety net, for the workers or local infrastructure," Beiersdorfer said. "It's another example of industry coming here, extracting the resources, taking the profits out and leaving the devastation behind."
Like other environmentalists, she is happy that President Barack Obama recently issued a temporary block on the Keystone XL pipeline, which proposed to move massive amounts of unconventional oil from Canada's tar-sands through the US heartland.
Concerns about water contamination have led several jurisdictions, including the state of New York, France, the Canadian province of Quebec and Bulgaria to suspend or ban hydraulic fracking. Images of blue flames gushing from rural faucets, along with pipelines and drilling stations cutting through rolling fields entered the popular imagination with the release of the Oscar-nominated documentary film Gas Land.
"We are seeing a lot of litigation, where individuals are claiming their drinking water is being contaminated or they are otherwise facing health risks from gas development," Sinding said.
While earthquakes have garnered significant media attention, problems like water quality - which often are presented as a clash of numbers between various scientists - are harder for the press to explain. Contamination happens over time, rather than in sudden shifts of tectonic plates, so it can be harder for people to notice.
"With the attention this [earthquakes and problems linked to fracking] is getting now, I hope we don't just go back to business as usual," professor Armbruster said.
Follow Chris Arsenault on Twitter: @AJEchris