Xcel Energy demolishes coal-fired power plant in Granite Falls
GRANITE FALLS, Minn. — Nearly 94 years of history disappeared with a boom and plume of black carbon as Xcel Energy imploded its decommissioned Minnesota Valley coal-fired electric generation plant Thursday morning in Granite Falls.
“Unbelievable,” Dallas Iverson, a former employee of that plant, said as he watched it crumble onto itself in mere seconds. “I just can’t imagine that it would come down like that. All that steel.”
Xcel Energy will now clean up and recycle the concrete, brick and metals from the plant’s structure, including iron, steel, copper, aluminum and brass, according to John Marshall, Xcel Energy regional vice president for Minnesota, South Dakota and North Dakota. Marshall said the removal will continue through the remainder of the year, and possibly into early next year.
The plant site on the east side of Granite Falls will be returned to a green site. Xcel Energy will continue to maintain and operate a large electrical substation at the site for its transmission grid in western Minnesota.
The coal-fired plant was originally built in the late 1920s, and began producing 20 megawatts of electricity in 1930.
“It was quite a beast for its time,” Marshall said.
The plant powered rural communities and farms in southwest Minnesota all the way to Sioux Falls, S.D.
The plant was expanded in 1953, and generated 70 megawatts of electricity for many of its operating years. While new and larger plants were coming online, it remained important for maintaining voltage in the transmission grid, Johnson said. It ended electric generation in 2004.
The implosion by Veit Construction, of Rogers, followed a process that began with the plant’s official retirement in 2009. In the past decade, Xcel Energy has removed the ash from its on-site landfill. The asbestos and equipment in the plant was removed in recent years to set the stage for the carefully choreographed implosion.
Many former power plants have been destroyed in recent years. As part of its transition away from coal and toward cleaner fuel options, the Tennessee Valley Authority used dynamite to demolish an old fossil plant in Alabama last year. Similar demolitions also happened in Florida, Arizona and Illinois.
The Granite Falls demolition required the temporary closure of U.S. 212 where the plant and its twin stacks towered 280 feet over the Minnesota River Valley.
“Now you’ll never know you’re coming into Granite,” Verlyn Kling, a former employee of the plant who joined Iverson in witnessing the implosion, said of the loss of the longtime landmark. “You could see the stacks four to five miles down the road.”
Now, Kling opined that motorists coming through town will wonder: “What little town is this?”
“That was our life,” Kling said as he and Iverson watched as dust continued to waft from the pile of rubble.
Iverson said he suspects that the plume of black that occurred as the plant crumbled came from the west stack erected in 1929. It emitted coal smoke nonstop until 1973, when it was replaced by the east-side stack that was installed with pollution-control equipment.
Iverson had worked at the plant from 1964 through 1996, and Kling from 1966 through 2000.
A part of the town’s heritage is gone with the plant’s disappearance, said Granite Falls Mayor Dave Smiglewski. Granite Falls had long called itself the “power city,” and its high school teams were once known as the Kilowatts.
“It’s a loss, for sure,” Smiglewski said. There were ups and downs in the city’s relationship with Xcel Energy, but the plant was always important. It was one of the town’s largest employers through most of its history, he noted.
The plant was also an important part of the city’s tax base. The mayor said the tax loss is lessened by the fact that the electrical substation remains on the site.
“It was a big part of the town’s life,” the mayor said. Now, he pointed out, all that is left is a large pile of debris for Xcel Energy to remove.
3 weeks of prep, 250 pounds of explosives
It took three weeks of preparation work, 250 pounds of explosives and a push of a button to send the ignition to those explosives at a speed of 6,000 feet per second to collapse the structure, according to Jerry Carlson, project manager for Veit Construction.
The explosive charges had been placed on three of five rows of steel columns on the second floor of the structure. In a microsecond, two explosions occur. The first explosion cuts the steel columns “like a razor,” he said. Charges fastened behind the columns explode and blow or push the columns in one direction, he explained.
It worked perfectly, dropping the building on itself in a north to northeast direction, and preventing harm to the electrical substation and a transmission line at the site, according to the project manager. The farthest any of the debris from the implosion traveled from the center of the building would have been 1,000 feet, and anything that went that far would have been very small in size, he said.
His crew had removed 200 tons of steel from the structure as part of the preparation for the implosion, and wrapped the columns with rubber belting once the charges were fastened to help contain the material.
The structure contained about 5,500 tons of steel total, he said.
This was the third coal-fired power plant in as many weeks that he and his crew have imploded. Overall, he said the size of this plant ranks as “average” in comparison to the power plants he has imploded.