NORM In Produced Water Discharges in the Coastal Waters of Texas

Abstract

ABSTRACT The Louisiana Department of Environmental Quality has reported elevated levels of naturally occurring radioactive material (NORM) in some discharges of waters produced in association with oil and gas production in Louisiana.1 Also, a NORM survey conducted by the American Petroleum Institute (API) found elevated NORM levels in production equipment in certain geographical areas of Texas.2 The Railroad Commission of Texas (RRC) became concerned about the possibility of elevated levels of NORM in produced waters being discharged to surface waters in Texas. However, the Railroad Commission realized it did not have the staff resources to undertake a massive NORM study. Therefore, RRC staff sought a means to utilize existing data to predict NORM levels in produced waters discharged in Texas. Barium is required to be reported as part of the RRC's discharge permit application. Barium is chemically very similar to radium. Therefore, RRC staff felt there might be a relationship between barium and radium levels in produced waters. A NORM survey was conducted on produced waters being discharged along the coast of Texas. Thirty-five discharges were selected for this survey based on their geographical location and varying concentrations of barium in their produced water discharges. The operators responsible for these discharges were asked to sample and test the discharges for certain chemical parameters, and to determine radioactive exposure levels in these discharges. In addition, the responsible operators were asked to submit geographical and geological information relevant to their discharges. The information supplied by operators was studied to determine whether correlations existed between radium 226 and other chemical constituents of produced waters. Geological information was also studied to try to determine if geologically "hot" formations could be identified. The studies showed that the Frio formation produces water with higher NORM levels than the Miocene formation. No direct relationship between barium and radium 226 could be found, but test analyses did show that a relationship exists between total dissolved solids and radium 226. This relationship was used to project levels of radium 226 in other active produced water discharges along the Texas coast.