Vapors from petroleum leak on University of Minnesota detected miles from scene

Vapor readings connected to a reported petroleum leak at the University of Minnesota were detected miles away from the campus, the Metropolitan Council revealed on Wednesday, as the investigation into the leak continues.

In an investigation update on Wednesday, the Met Council, which oversees the regional sewers, says investigators are working to determine where the suspected petroleum came from.

Residents near the campus were evacuated late Tuesday morning after contractor crews with the council stumbled upon the apparent petroleum in the sewer tunnels near 5th Street SE and Oak Street, not far from Huntington Bank Stadium.

The Metropolitan Council says the crews experienced low oxygen and eye irritation from the fumes but were able to track the vapors north to Hennepin Avenue stretching to the area of Stinson Boulevard.

The incident this week followed another round of evacuations in late June after another sewer leak caused an explosion that knocked off manhole covers along University Avenue. Vapor readings from that incident stretched from the university to the area of Fridley, Minnesota, the Met Council reported Wednesday. That's about an 8-mile stretch as the crow flies.

The agency says they are working to determine if the substance was directly discharged into the City of Minneapolis sewer system or the regional sewer system -- which the Met Council oversees.

According to the Met Council, both sets of pipes show signs of a "black, oily substance" or an odor. They are also now checking with industries in the area with large petroleum storage tanks.

The Met Council is working with the state's Pollution Control Agency to test samples from the incident as well. According to the council, they were able to collect multiple samples from this week's incident.