Updated

South Park, PA -- One day before the Pennsylvania primary, a critical battleground state in the upcoming general election, Mitt Romney addressed what will likely become a key issue during the fall - energy.

Surrounded by employees at Consol Energy's Research and Development Facility, Mr Romney assailed President Obama's policies, blaming them for the increase in energy prices.

"The onslaught of regulations -- holding off on drilling in the Gulf; holding off on drilling in the Outer Continental Shelf; holding off on drilling in Alaska; trying to impose the federal government into fracking regulations...all the regulations relating to coal," Mr Romney said, ticking off a list of policy decisions made or continued by the Obama Administration. "These things have made the cost of energy go up."

Mr Romney has made energy independence a continual refrain on the campaign trail, advocating a policy using all energy sources in order to break America's dependence on foreign sources of energy. He has repeatedly criticized the President for relying too heavily on renewable energies - solar and wind - at the expense of more traditional, carbon based fossil fuels.

"How in the world the President says, as he did the other day, he's for all of the above when it comes to energy," Romney pondered before the crowd of about 150 people. "I couldn't figure that out given his policies. And then it struck me - he's for all of the sources of energy that come from above the ground, alright. Wind and solar. He just doesn't like the things that come from below the ground."

The Obama campaign quickly fired off a release, defending the President's record, while attacking Mr Romney for not telling the truth about his own energy record as Governor of Massachusetts and accusing Romney of being in the oil industry's pocket.

"President Obama has aggressively pursued an all-of-the-above energy strategy. As domestic oil production has reached an 8-year high and our dependence on foreign oil has fallen to a 16-year low, the President has also made historic investments in renewable energy, reduction of energy waste, the R&D of clean coal technology and expanded safe natural gas extraction," campaign spokesperson Lis Smith said in a statement.

"Mitt Romney, on the other hand, raised a gas tax by 400% as governor of Massachusetts and has opposed increased fuel economy standards that will save families $8,000 at the pump on the average vehicle."

Consol Energy, where Mr Romney spoke today, is the largest coal producer east of the Mississippi River, according to their website, and has become a large player in Marcellus Shale - a layer of rock below large portions of Pennsylvania, Ohio, New York, and West Virginia rich in natural gas. They employ more than 8,880 people across the country, 2,400 of whom work in Pennsylvania.

Over the past decade, shale gas has become one of the largest industries, and a source of hope, in a region devastated by the collapse of the American steel, auto, and coal industries. New technologies and drilling techniques have opened vast reserves previously thought unobtainable.

And Pennsylvania sits at the center of this boom. Some industry experts estimate up to 100,000 energy related jobs have been created in the state, contributing tens of billions of dollars to the state's economy.

But it's not without controversy.

The potential for accidents and an unwillingness by energy companies to be fully transparent with their operations have pitted economic expansion against environmental protection. Shoddy drilling methods and poor well casings have led to water supplies being contaminated. And the process of extracting the gas through hydraulic fracturing - or "fracking" - has been extremely controversial.

Fracking involves pumping millions of gallons of water mixed with sand and chemicals - some hazardous - at high pressure down a well and into fractures in the rock in order to release trapped gas. The wastewater produced must be stored and treated to remove toxins before being reused, but has on occasion leaked out of storage ponds.

New York State has had a moratorium on fracking for the past three years pending the results of an environmental impact report for fear of contaminating New York City's water supply (reservoirs for the city are upstate, where the Marcellus shale runs). Governor Andrew Cuomo supports developing the gas industry, which is estimated to create up to 54,000 much needed jobs, but says he wants it done safely and correctly.

Pennsylvania is one of the friendliest states in the country toward the gas industry, encouraging growth through a light tax burden and keeping regulations at a minimum. It also has the largest number of reported accidents related to gas drilling of any state, according to a study published by the Massachusetts Institute of Technology.

Consol Energy prides itself on being environmentally aware, promoting its green record and history of environmental protection on its website. And while its fracking operations have had no reported incidents, the company paid a $5.5 million dollar fine to the United States Department of Justice in 2011 in association with a fish kill in West Virginia. The Environmental Protection Agency claimed that Consol's mining operations polluted a nearby creek, resulting in a large algae bloom, but the company maintains it was never found liable for the fish kill.