Here is recent AP article HollyFrontier planning injection well & having wastewater / disposal issues with Selenium-contamination. The Cheyenne Refinery/Coker has been revamped to handle both Heavy Canadian Crude and nearby
Shale Oil crude from Niobara & Bakken Shale Oil.
Most of the Shale Oil Crudes like Utica, Niobara, Bakken are known to have high levels of Arsenic, Selenium, Strontium, Barium and sometimes Mercury levels instead of normal Crude high levels of Vanadium, Nickel, Silicon, Iron and Copper.
The difference in type metals are going to be hard on wastewater disposal given the serious nature in these metals (especially Arsenic, Selenium, Strontium and Mercury) compared to conventional crude heavy metals. Perhaps this is early indicator of the problems?
Regards, Charlie Randall
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