There are hundreds of thousands of oil, gas and water wells in West Virginia. How likely are they to cause problems for each other?
In West Virginia's natural gas boom, a potential concern is what might happen when the maze of underground wells intersect. There have been documented cases of deep Marcellus drilling and high-pressure fracking connecting with older wells.
Jim O'Reilly is an expert in regulation and liability. He says given the hundreds of thousands of wells, it's likely there are more problems no one knows about, that could be more frequent in the future. O'Reilly says a lot depends on the stability of underground concrete well casings. He adds, "Anyone that's walked on a crumbling sidewalk realizes that concrete has a life. It may be a matter of a year, it may be several years - but inevitably, the concrete in the wells will fail."
According to the West Virginia Geological and Economic Survey, the industry has drilled more that 150,000 oil and gas wells in the state. The industry and state regulators contend that a properly constructed well casing should keep the pressure from Marcellus wells from traveling along natural cracks in rocks and connecting with other wells.
