Enbridge has had at least 28 “frac-outs” while tunneling under Minnesota streams and wetlands to install its Line 3 tar sands pipeline. These have released between 10,000 and 13,000 gallons of “drilling mud,” according to data released by the Minnesota Pollution Control Agency (MPCA).
The drilling process requires using a special drilling mud that helps lubricate and cool the drill bit. The mud is under pressure and can get forced into subsurface soil cracks and pushed to the surface. This is called a frac-out. They can happen on land, in wetlands and in rivers and streams.
Line 3 drilling under the Mississippi River in Aitkin County resulted in the largest single spill, estimated between 6,000 and 9,000 gallons. It occurred in a wetland about a quarter-mile from the river, the MPCA said.Continue reading