... map of the OSPER ‘A’ site showing the locations of the oil pits, other production features, drilled water wells and outline of the impacted area. Environmental impacts of petroleum production: ... settings of the Lester and Branstetter leases resemble that of much of the major southern mid-continent oil- and gas-producing area of the U.S. The leases are also typical of many depleted and aging ... wells, and simply running the water over the ground. Impacts of these past practices are apparent in salt scars, dead trees and other vegetation, contamination of soil and surface water, and plumes...