In some cases, no drilling occurs and the lease simply expires. However, a well may in fact be drilled. We'll assume here that drilling is viewed as a good thing by Jun 27, 2018 A map illustrating oil and gas wells within the City of Los Angeles can of Public Works – Office of Petroleum and Natural Gas Administration Oct 15, 2018 Media captionThe BBC's David Shukman explains how fracking works. Drilling companies suggest trillions of cubic feet of shale gas may be Hydraulic fracturing, or fracking, is a technique designed to recover gas and oil from shale high pressure which allows the gas to flow out to the head of the well.