Stadium could unearth buried pollutant

Brad Unangst

It’s thick and black and causes cancer, but it’s not the tar found in cigarettes.

It’s creosote – a wood preservative once used on telephone poles and railroad ties – and it can be found beneath the Huron Boulevard Parking Complex, according to a 1997 environmental report commissioned by the University.

The pollution poses no danger while covered by asphalt, but construction of a proposed Gophers/Vikings football stadium on the site could increase the risk of further contamination, University and Minnesota Pollution Control Agency officials said.

The Gophers and Vikings have proposed building a 64,500-seat stadium on the Huron complex site, but the plan needs state legislative approval before moving forward.

University hydrogeologist Roman Kanivetsky said ground water contamination is the most critical issue for construction on the site.

“The area is highly susceptible to contamination because the soil is permeable,” Kanivetsky said. “It’s mainly sand and gravel.”

Chemicals uncovered during digging could easily seep through the sand and gravel down to the 20-foot ground water level, Kanivetsky said.

Those same types of chemicals would also contaminate soil in the area, said Calvin Alexander, University geology professor.

But ground water and soil pollution isn’t the only concern, said Gerald Stahnke, an MPCA project manager.

Construction workers and others at the site risk coming in contact with exposed creosote, Stahnke said.

“Creosote is a carcinogen, which can cause cancer,” Stahnke said.

He said exposure could occur through touching, inhaling or ingesting the substance.

University and MPCA officials said they are unable to determine the extent of possible contamination until a site analysis detailing the concentration levels and kinds of contaminants is completed.

Stahnke said the creosote contamination could possibly be linked to Republic Creosote, a creosote treatment facility that once operated on the site of the University’s Buckeye lot before closing in 1916.

Stahnke said Republic created a “pond” of creosote to soak wood poles. When finished with the treatment process, the company covered the pond. Over time, the creosote could have seeped into the ground water or sat until disrupted by soil removal around the pond and contaminated the land.

In 1995, prior to the University’s purchase of the land, the MPCA supervised a cleanup of the site, which removed 5,500 cubic yards of contaminated soil, Stahnke said.

“We encountered contamination that expanded beyond the cleanup site,” Stahnke said. “But we were limited to how far we could dig (out the pollution) by the road.”

According to a 1997 environmental report issued by Peer Environmental and Engineering Resources for the University during construction of the bike path along Sixth Street Southeast, polluted ground water was found in the area.

Water sampling showed pollution underneath Sixth Street just south of the Buckeye lot and under the parking lot north of the transitway.

Lynne Grigor, an MPCA hydrogeologist who helped evaluate the Republic site, said it is difficult to determine exactly where the creosote comes from without further investigation.

“Contamination could be coming from below the parking lot or left over from the cleanup site,” Grigor said.

The report indicated additional soil and water cleanup would be required before any future University construction could occur.

The proposed $500 million stadium has contingencies built into the cost to help with unexpected construction costs such as pollution cleanup, said University chief financial officer Richard Pfutzenreuter.

“The (stadium estimate) doesn’t have a specific line for the environmental costs,” Pfutzenreuter said. “You’re never sure at this stage of the game specifically how much the environmental issues may be.”

Alexander said the site has a better chance of getting cleaned up when a large stadium is built. The site has some things to check up on, but he does not think any are “show stoppers,” he said.

“If you’re going to build a half-billion-dollar building, the cost for cleanup is a drop in the bucket,” Alexander said.

Brad Unangst welcomes comments at [email protected]