Quantifying the Impact to Surface and Ground Waters Using Oklahoma Corporation Commission Compliance Reporting

Abstract

Given increasing oil and gas drilling activity as a result of the new technologies of horizontal drilling and hydraulic fracturing, many Oklahomans have been concerned about pollution to surface and ground waters. Two studies were conducted to quantify the potential impact to the state waters using Oklahoma Corporation Commission (OCC) compliance reporting. The first study was focused on ground water and analyzed alleged pollution to water wells and documented salt water spills. A total of 38 water wells were allegedly reported contaminated by their owners between May, 2012 and May, 2013. Eight of these water wells were referred to pollution abatement by the OCC as confirmed cases of oil and gas related water pollution. Five of these incidents were surrounded by a mix of older and newer production wells and two incidents were surrounded exclusively by newer production wells. During the same period, 333 saltwater spills were recorded by the OCC. The potential of those spills to pollute shallow ground water was determined using DRASTIC indices assigned by the Oklahoma Water Resources Board. It was determined that 25% of the reported salt water spills had occurred above high or very high vulnerability aquifers. The second study focused on the potential impact from salt water spills to drinking water surface intakes using data from the OCC and the Oklahoma Department of Environmental Quality. It was concluded that 16 surface water bodies had been affected by salt water spills. The most proximal distance of a salt water spill to a surface drinking water intake was two miles.