Oilfield brines wasting into the Green River created an acute pollution problem over 100 miles in extent. Before August, 1958, the water was moderately hard, of the calcium magnesium bicarbonate type, and had an average chloride concentration of less than 10 ppm. With the disposal of brines coincident with the rapid development of the Greensburg oilfield in the spring of 1958, the water became very hard, changed to a sodium chloride type, and chloride concentrations frequently exceeded 1,000 ppm. The effects this pollution had on the water quality, fish fauna, and macro-invertebrate bottom fauna were determined and evaluated in a study that began in the summer of 1960 and continued through 1963. Domestic and industrial use of the water was seriously affected, as were private springs and wells. Ground water contamination was concentrated in the areas of greatest brine production in Green and Taylor Counties, but was noticeable as far as Brownsville, 100 miles downstream. The two large springs in Mammoth Cave National Park, known as Echo River and Styx River, also became contaminated. Population sampling showed that the Green River supported an extremely rich and varied fish fauna, especially in the unpolluted sections. One hundred seven of the 177 species known to occur in Kentucky were identified from the river during the 4-year study. As the brine pollution diminished from its peak intensity in 1960, the number of species occurring exclusively in the unpolluted section decreased from 27 in 1960 to 13 in 1963. The unpolluted section supported an average annual standing crop ranging between 85 and 156 pounds per acre. The standing crop in the polluted section increased from 10 pounds per acre in 1960 to 47 pounds per acre in 1963. The effects of brine pollution on the macro-invertebrates were just as pronounced. The upstream, unpolluted section of the river supported a rich and varied bottom fauna. Productivity in this section averaged 90 organisms and 1.78 cc, per square foot, over the 4-year period. Procductivity values in the polluted section during the year of greatest pollution ranged from an average of 26 organisms and 0.18 cc at Station +6.2 (closest to pollution source) to 78 organisms and 0.64 cc at Station +80.4 (farthest from pollution source). The quality (i.e., as potential fish food) of the bottom fauna in the polluted section was extremely poor. However, both quality and productivity showed improvement as the brine pollution gradually diminished.
