The Wyoming State Geological Survey (WSGS) published a new
 study in its ongoing series that examines water quality in selected Wyoming energy-producing basins. The latest report focuses on the Greater Green River Basin in southwestern Wyoming.

“This report is a continuation of a series that considers groundwater salinity, which is one method to determine the quality of water for various uses,” says WSGS Director and State Geologist, Dr. Erin Campbell. “The study was done in the Greater Green River Basin, an area where natural gas drilling continues, and the need for water to support oil and gas production is important.”

Earlier this year, the WSGS published a statewide salinity report, and previous to that, published studies about the Denver-Julesburg and Powder River basins. The reports are available as free downloads on theWSGS website.

“Salinity,” or total dissolved solids, is the amount of dissolved material that remains as residue after the liquid portion of a water sample evaporates. The Wyoming Department of Environmental Quality uses salinity to determine if groundwater resources are suited for human consumption or agriculture. In Wyoming, saline groundwater is encountered most frequently as a byproduct of oil and gas exploration in deep basin aquifers.

For this report, WSGS geoscientists considered groundwater salinity at depths of 1,000–7,000 feet in certain geologic structures within the Greater Green River Basin, including the Green River Basin, Overthrust Belt, Great Divide Basin, Washakie Basin, and Rock Springs Uplift.

The study shows groundwater salinity commonly exceeds 5,000 parts per million at depths greater than 3,000 feet throughout the basin, says Karl Taboga, WSGS hydrogeologist.

“In fact, saline groundwater can be found in the 1,000–2,000-foot depth interval in wells along the Lincoln-Sweetwater county line, as well as the southern boundary of Carbon and Sweetwater counties,” Taboga says. “Groundwater resources are more limited in the Greater Green River Basin than elsewhere in the state, so it is important to conserve fresher waters for domestic and agricultural use by using saline water for energy development and mining, whenever possible.”

The report additionally details current beneficial uses of saline groundwater in Wyoming, industrial applications for saline groundwater, and methods used in the study.