How Gas from the English #1 Well Escaped and Invaded Residential Homes Causing One to Explode, Geauga County, Ohio
Early in the morning on December 17, 2007, stray gas from construction of the English #1 gas well in Bainbridge Township, Ohio, caused a residential house to explode and a nearby water well to spout 15 feet above the land surface. Beginning that afternoon and continuing for two years, the Ohio Department of Natural Resources (ODNR) routinely measured methane concentrations (i.e., lower explosive limits) in basements of homes and in the headspace of residential wells. A lawsuit filed in county court centered on interpretation of how the methane traveled from the gas well to nearby properties. In an effort to settle the lawsuit through arbitration, ODNR, which was not a party in the lawsuit, set-up a panel of experts to review existing data and to identify additional types of data it needed to determine of how the stray gas migrated to the other properties. The expert panel consisted of professors from three different universities in Ohio: a petroleum engineer, an aqueous geochemist, and a hydrogeologist.
Construction of a site-specific, structure-contour map of the top of the Berea Sandstone, the major aquifer tapped by local water wells, indicated that stray gas from the English #1 well would migrate northward into a dome-like structure, overlain by the highly-jointed Cuyahoga Shale, with a spillover point on its eastern edge. The methane measurements made in residential wells confirmed this migration pattern. Borehole videos taken in several residential wells directly after the home explosion were repeated in 2009. Comparison of videos made in the same wells showed the bottom of the (stray) gas cap was migrating vertically out of the Berea Sandstone, up into the Cuyahoga Shale. The deliberate overpumping of 16 residential wells for up to 7 months augmented this natural attenuation of stray gas. The upward movement of the gas cap indicated accidental overpressurizing of the annular space following a substandard cement job in the English #1 well did not create multiple networks of fractures connecting the Clinton Sandstone production zone at a depth of 3700 feet with the Berea Sandstone aquifer, as posited by one expert. The upward movement of gas cap also indicated that natural gas from the production zone would not act as a perpetual source of hazardous gas that could invade homes and water wells forever, as alleged in the lawsuit.
AAPG Search and Discovery Article #90154©2012 AAPG Eastern Section Meeting, Cleveland, Ohio, 22-26 September 2012