After years of spreading cinders on city streets for snow removal, Columbia is beginning to lay the groundwork to use salt as the primary snow-removing substance.
Cinders, a waste product from the coal-fired Municipal Power Plant, are economical because they’re free. And cinders aren’t corrosive to pavement or vehicles.
But complaints about the mess that cinders create are as predictable as the arrival of winter, and there’s $125,000 in the budget this fiscal year to buy property for a salt storage facility.
“There’s a perception in the community that salt is cleaner,” said Dennie Pendergrass, chief of operations for the Columbia Pubic Works Department. “People don’t like cinders being tracked into homes and cars.”
Cleaner, but at what cost?
But the cleaner salt has its own set of problems, including higher costs and corrosion. The Public Works Department estimates that switching to salt would cost $375,000 for new facilities and equipment alone.
Though switching to salt is a multistep process that would need approval of the Columbia City Council, Pendergrass said it’s possible, but not likely, that everything could be in place as early as the winter of 2004-2005.
Fourth Ward Councilman Jim Loveless said salt might not be the only solution. He pointed out the negative aspects of using salt, including the amount of money needed to switch.
“If the primary complaint is that it makes your rugs dirty, then maybe we need to reconsider the other costs involved,” Loveless said. “It’s corrosive to cars, a soil sterilant, a relatively pervasive pollutant of water, not as stable as cinders (because it binds in chunks when it gets wet), plus it creates a new problem — getting rid of the cinders.”Converting to salt would require a dome-style storage building with a conveyor system, new spreader meters for trucks and a 10,000-gallon liquid-calcium-chloride dispenser.
New storage and new materials
Along with more salt and liquid calcium chloride, about 500 tons of sand would be needed as well.
“Under this strategy, we’ll replace all cinder with salt and sand,” Pendergrass said. He said the liquid calcium chloride is used when temperatures fall to 5 or 10 degrees.
Current storage facilities hold 500 tons of salt and about 10,000 gallons of liquid calcium chloride. Pendergrass said a new building would likely hold 4,500 to 5,000 tons of salt and another 10,000 gallons of liquid calcium chloride.
“If you’re going to build a building, you want to have enough to last for the entire winter,” Pendergrass said. He said price and availability are better in the summer.
Snow and ice removal mixtures
During his 28 years with Public Works, Pendergrass has seen a slow shift from using only cinders to a mix including other materials. A storage facility built in the early 1980s enabled the city to switch from bags of salt to bulk salt. Around that time, Pendergrass said, liquid calcium chloride also was added to the mix.
Two decades later, cinders, salt and liquid calcium chloride are still the materials used by the city for snow and ice removal.
The Boone County Public Works Department uses a slightly different formula that varies depending on the type of road, according to Public Works Director David Mink. On paved roads, fine rock and salt is used; 3/8-inch limestone chips for traction are applied to chip-and-seal and gravel roads. He said some contractors in subdivisions use salt but only at intersections and steep hills.
Ted Johnsen, superintendent of the city power plant, said he doesn’t foresee a problem in disposing of the cinders because they are used by the state and agencies in other counties. “When we don’t have a lot of snowfall it builds up,” he said, “and when the snow comes, it goes pretty fast.”