A race is on to extract natural gas from vast swathes of the US. But is hydraulic fracking the cure for an energy-hungry country or a fatally flawed process that will have disastrous consequences for people and the environment?
Estimates of vast deposits of shale gas under US soil have led to intense pressure from industry and the government to extract it - in a process known as hydraulic fracturing or fracking.
Its backers say that hydraulic fracking is the answer to the US' energy crisis and a way to prise the US away from its dependency on foreign oil.
But there is increasing evidence that fracking comes at an enormous cost to health, with reports of highly toxic chemicals seeping into water supplies.
The industry has spent vast sums of money lobbying the US Congress to avoid government regulation of its practices.
But now there are even new doubts emerging over the much-touted positive economic benefits fracking brings to the communities it so profoundly affects.
So, does hydraulic fracking come at too great a cost to our health and environment?
Joining Inside Story Americas, with Shihab Rattansi, to discuss this are: Bernard Goldstein, an emeritus professor from the University of Pittsburgh Graduate School of Public Health who has testified before Congress on this issue; Michael McKenna, formerly with the energy department and now president of the corporate communications company MWR Strategies; and Josh Fox, the director of the Oscar-nominated documentary, Gasland, about the natural gas drilling industry.
- Hydraulic fracturing or fracking is used to extract gas from shale rock
- Fracking involves pumping water and chemicals into the veins of shale rock
- Marcellus Shale is the largest known natural gas reservoir in the US
- Marcellus covers parts of New York, Pennsylvania, Ohio and West Virginia
- Most of the shale gas reserves in the Marcellus area remain untapped
- More than 4,000 fracking wells are in operation in Pennsylvania
- Potentially toxic methane levels have been found in drinking water near the wells
- Many residents who live near fracking wells say their water has been contaminated
- Air pollution from drilling wells has also increased
- Wyoming failed to meet air quality standards due to fumes from wells
- Fracking backers say it will help reduce dependence on foreign oil
- Fracking backers say natural gas is two-thirds cheaper than oil
- The Obama administration has promoted the increasing use of natural gas
- Obama says the US has enough natural gas supply to last 100 years