During November 1975 and September 1976 a number of air samples were collected at ground level in an attempt to define the background concentrations of methane and ethane in a nonurban area south of Youngstown, Ohio. The area is primarily agricultural and is centered on a natural gas storage field. This region was chosen in order to determine whether the background concentrations of methane and ethane were being affected by leakage of natural gas from the storage field.