Tintina Resources has released a document explaining in detail the facility that they proposed in their permit application for storage of the acid-producing tailings from the Black Butte mine.
Here is a map from that document showing the close proximity to Sheep Creek of all the mining facilities. Tailings and storage ponds But note in particular the topographic elevation lines showing that the tailings storage area is at the top of a valley that descends down toward the access road, the county road and Sheep Creek.
Below is a closer view of the tailings facility that shows a stream running just east of the facility and the runoff catchment pond. This stream may only run seasonally but it shows the course that water naturally takes as it flows downhill toward Sheep Creek. If at some future time, leakage or seeps from the tailings facility develop, acid-laced water would follow that small stream down to Sheep Creek. The process water pond looks like it would sit to the northwest across a small ridge from the tailings storage area so leaks from there would not have as direct a route but it would still flow downhill to Sheep Creek.
To read more about the facility, you can download the document here.