Thick, black smoke billowed out of the University’s Southeast Steam Plant late last Tuesday morning, creating a cloud that could be seen from several blocks away.

The release lasted approximately 10 minutes — not long enough to result in any environmental fines but prompted several phone calls to Minneapolis firefighters and environmental inspectors.

Workers at the facility, which is privately operated for the University by Foster Wheeler Twin Cities, corrected the problem before firefighters and inspectors arrived.

University Services spokesman Tim Busse said a malfunctioning damper in one of the plant’s burners caused the plume. When working properly, the damper automatically regulates the amount of oxygen allowed into the burner. Last Tuesday, as staff was changing the plant’s fuel source from natural gas to oil, the damper didn’t let enough oxygen in, and the result was the thick, dark smoke, Busse said.

“It’s probably similar to what comes out of your car,” city environmental inspector Jennifer Tschida said of the substance. “Whenever you’re burning something, you get particulates in the air. You get carcinogens. You get benzenes.”

Black smoke is regulated according to opacity, or the amount of light that can pass through it, Tschida. In this case, the smoke had dissipated before she or her co-workers could attempt to get a measurement.

Tschida said it’s doubtful any fines would have resulted if she obtained a reading that warranted an offense because there are start-up exemptions for most machinery. The Southeast Plant had just started burning fuel oil from one of its above ground storage tanks.

Busse said the plant switched from natural gas to fuel oil to drain the storage tank so that Foster Wheeler could upgrade it to meet federal safety rules.

The Southeast Steam Plant, located at 600 Main St. S.E. near the Stone Arch Bridge, previously has prompted noise and aesthetic complaints from Marcy Holmes neighborhood groups. Busse said the University is working closely with those groups and that protests have calmed in the past couple of years. Plans to renovate parts of the facility are being finalized.

Dan Haugen welcomes comments at [email protected]