Gov. Martin O'Malley ordered Monday a study of the impacts of drilling for natural gas in Marcellus shale deposits in westernMaryland.

Acting on legislation passed by the General Assembly, the governor directed the Department of the Environment and the Department of Natural Resources to consult with an advisory commission yet to be appointed that will examine potential environmental and economic issues around the use of hydraulic fracturing to extract the gas.

Reports of well blowouts, spills, leaks and fires in neighboring states prompted the call for a study. Two companies have applied for permits to drill inGarrett County, in one case more than a year ago.

A report is due Dec. 31, in time for next year's legislative session, dealing with potential liability issues around the drilling technique and recommending whether to levy a state severance tax on gas production to pay for overseeing the industry. Another report recommending "best practices" for Marcellus shale drilling is due Aug. 1, 2012, with a final report on any other findings and recommendations by August 2014.