A move is under way in the U.S. to quantify human health risks, if any, from the radioactive constituents of the produced brines and brine by-products that are associated with produced oil and gas streams.
Residents that live near producing sites in Mississippi and other states have sued several current and former operating companies for damages related to alleged increased health risks. The risks relate to production streams, pipe scale, and sludge that may contain naturally occurring radioactive materials (NORM).
A lack of data makes such cases difficult to defend. Researchers are compiling a database of the NORM content of produced brines and scale leachate. The database could be used in epidemiological studies anywhere in the world.
Research in progress
NORM contamination has been found in wells in several states, including Louisiana, Texas, Oklahoma, Mississippi, and California (OGJ, Apr. 22, 1996, p. 65). Very little data exist on the concentrations and isotopic composition of radium, the main radioactive element contained in this type of NORM.Radium is considerably more soluble than either of its parents, uranium or thorium. Radium can become concentrated in pipe scale and sludges that may form during the production of oil and gas.
The Mississippi Office of Geology in Jackson is conducting a 4-year study with funds from the U.S. Department of Energy and the Office of Geology. The DOE grant resulted from a proposal made by the principal investigator, Rick Ericksen, of the Office of Geology.
Part of the study involves the collection of pipe scale and sludge to determine their mobility within the environment, such as under acid rain conditions. Samples of soils with elevated NORM readings from nonproducing areas have also been collected.
All samples will be analyzed for radium content and isotopic composition and further exposed to environmental conditions to determine the mobility of any radium they contain.
Researchers have collected nearly 1,400 l. of oil field brines from 172 wells in several fields and formations in the Black Warrior and Mississippi Interior Salt basins. More fluid samples are being collected, and researchers may also examine cuttings and cores where warranted.
Copyright 1998 Oil & Gas Journal. All Rights Reserved.
