Responsible development of shale natural gas in Ohio could spark resurgence of the economy for the state, a trade group said. Ohio hosts portions of the Marcellus and Utica plays, two of the richest shale deposits in the United States. Chesapeake Energy, one of the largest gas producers in the United States, said Utica could hold as much as 25 billion barrels of oil equivalent. American Petroleum Institute President Jack Gerard told officials in Cleveland that the Marcellus and Utica shale deposits could revitalize the state\'s economy. \"Responsible energy production has already generated more than $22 billion for the Buckeye State,\" he said. API is among those pushing for greater state control over hydraulic fracturing, the process used to extract natural gas from shale formations. The practice is controversial because of the potential for groundwater contamination from fluids used in the process. A series of small earthquakes in Ohio recently were attributed to the pumping of wastewater from shale gas operations.