ASHLAND, Wis. (WRN) — A northern Wisconsin tribe says a recent leak on an oil pipeline project requires its shutdown.

The Bad River Band of Lake Superior Chippewa want Canadian firm Enbridge Energy to shut down its Line 5 reroute project after drilling sludge leaked at a site in Iron County and into waterway.

The Milwaukee Journal Sentinel reports about 16 hundred to 19 hundred gallons of fluid spilled last weekend near Vaughn Creek which flows into the Bad River Reservation. While Wisconsin Department of Natural Resources and Enbridge report the spill contained, the Tribe says the incident proves the project threatens natural resources.

Enbridge is rerouting Line 5 because of the tribe’s successful legal action to remove it from the reservation.