The Environmental Protection Agency says it has narrowed the source of salt contamination in an Osage County creek to three nearby oil and natural gas injection wells.
The Tulsa World reports the contamination was first reported in August 2016 when an oily sheen appeared on North Bird Creek on the Chapman Ranch in Osage County, a few miles from the Tallgrass Prairie Preserve.
The contaminated water would be deadly to cattle and horses. Ranch operators moved livestock about two miles away from the stream. Hundreds more were sold.
EPA District 6 spokesman David Gray says an investigation has identified three injection well operators as likely sources. They were not identified.
Gray says EPA scientists are recommending the companies test their systems to see if they are impacting Bird Creek.