A chemical smell that has wafted through the West Bank campus since February should soon go away for a month before returning.
The smell comes from the process of cleaning carcinogenic compounds from soil at Minnegasco’s former Minneapolis Gas Works site. The first phase of the cleanup project should be completed in the next two weeks, but the second phase of the project is scheduled to begin in late August.
The project has an estimated price tag of $7 million to $10 million, which will be paid entirely by Minnegasco, said Patty Pederson, spokeswoman for the company.
Minnegasco has already disassembled a machine located on the treatment site, which is on the west bank of the Mississippi River almost underneath the Interstate 35 bridge. This machine heated soil to about 1,100 degrees Fahrenheit to break down the contaminating compounds.
Emmy Reppe, spokeswoman for the Minnesota Pollution Control Agency, said the smell came from moving and crushing the contaminated soil, and people who notice the odor are not put at a health risk.
“It’s true that the odor will sometimes make people who are sensitive to smells sick to their stomach,” Reppe said. “But as far as health concerns go, there aren’t any.”
She added that the air around the site was carefully monitored.
“We had air-quality monitors around the site at all times and any time the odor got particularly bad, the crew would walk around with a hand-held monitor,” Reppe said.
But some people on the West Bank have complained of bad smells.
Last winter, some employees in the West Bank Office Building, which houses the Department of Epidemiology and other University offices, said they had more headaches and other symptoms of illness than usual.
Bill Ryan, a network administrator who worked in that building, reported blinding headaches.
“I wouldn’t have it and as soon as I got (to the building), I’d have it in half an hour,” he said.
The workers’ symptoms might have been caused by a broken ventilation system in the building, rather than the soil treatment project. Gordon Girtz, project manager for Environmental Health and Safety, works on an advisory committee that makes recommendations to Minnegasco about how to handle the cleanup. He said symptoms might also have been caused by fumes from traffic on the nearby interstate.
“The symptoms could not be attributed to Minnegasco exclusively or the building exclusively,” Girtz said. The ventilation system has since been fixed.
Minnegasco’s Pederson said when the second phase of soil treatment begins, a temporary structure will cover the area where soil is being handled. The structure will include an air-filtering system, which should help reduce odors.
A structure was not used during the first phase of cleanup because the cleanup took place in a limited space and was originally scheduled to end before summer arrived and heat intensified the odor, Pederson said.
Tracy Siegfried, maintenance assistant at the Seven Corners Apartments across from the Law School, was skeptical that the temporary structure would make much of a difference.
“If they built a brick structure with a vent, that’s the only thing they can do to get rid of that smell,” Siegfried said.
Second-year law student Jen Willey lives in the same apartment building, but she said the smell hasn’t bothered her. “I really haven’t noticed anything.”
During the current phase, workers treated about 60,000 cubic yards of soil held in a tank at the site. During the 90 years when the facility turned coal into natural gas, the tank held manufactured gas. That gas circulated in Minneapolis through hollow logs and was used in stoves and street lights before the natural gas pipeline was installed.
In late August, Minnegasco plans to treat soil in a larger area east of the current work site. As workers treat this soil, they will also grade a road bed for the last link of the West River Parkway. When that link is completed, the road will stretch continuously from St. Anthony Falls to Minnehaha Falls. If the soil cleanup is completed this year, as planned, and the park board acquires 2 to 3 acres from Minnegasco, construction of the road might begin as soon as spring.