(Billings, MT – YPR) – The Montana Department of Transportation uses a “green” anti-corrosion inhibitor in its liquid chemical road de-icer.
The state agency recently awarded a one-year contract to Rivertop Renewables of Missoula, MT to provide about 110,000 gallons of corn-sugar to mix with its salt brine de-icer.
“Essentially MDT will put sugar and salt on our roads to keep winter drivers safe and our state’s economy flowing, while protecting infrastructure investments and our environment,” says Rivertop President Jere Kolstad in a press release.
Dr. Dave Wilkening is the company’s manager of corrosion sciences. He says he’s been working to develop an inhibitor that’s bio-based and bio-degradable. Wilkening says he grew up in the Midwest, “and have vivid memories of cars with holes in the floor boards and fester rusted off” from either road salt or liquid de-icers sprayed on the roads during the winter.
He says the alternative – phospate-based corrosion inhibitors – aren’t environmentally friendly and are being phased out at the request of state transportation departments.
Montana, Idaho, Washington, Oregon and the Canadian province British Columbia joined together several years ago to develop specifications for the chemicals used to combat snow and ice on roadways. The group is known as the Pacific Northwest Snowfighters Association. According to its website, it was formed to evaluate and establish specifications “for products used in winter maintenance that emphasize safety, environmental preservation, infrastructure protection, cost-effectiveness and performance.”
MDT winter maintenance specialist Justun Juelfs is a member of the committee. He says bio-inhibitors are a fairly new product in the market. He says Montana has been producing a liquid salt brine de-icer for the past 5 years, “So we asked the industry to develop a product that meets or exceeds our corrosion protection standard.”
Juelfs says using a “green” corrosion inhibitor is not new to MDT. “Essentially the product that we’re using this year, that was sourced through Rivertop, is essentially the same active ingredient that we’ve been using for years in the past.”
Juelfs says while Rivertop Renewables is a Montana-based company, that fact did not lead to any special preference. He says every bidder has to abide by the same rules. “Rivertop was the successful bidder based on low bid,” he says.
Juelfs says the company was awarded a one-year contract for its anti-corrosion inhibitor and that was done purposely.
“We have more and more players at the table each year,” he says. “So multiple year contracts would discourage future competition. And until salt brine corrosion inhibitor becomes more readily available and there’s additional vendors willing to supply that, we just stick with an annual contract because at this point it is in the state’s best interest to do so.”
Juelfs says Montana doesn’t require vendors for an anti-corrosion additive to be bio-based, but he says the state has stringent environmental requirements. For example, he says the state tests for heavy metals, Ph, and the biological oxygen demands, “so we know we’re not impacting the adjacent streams and rivers to our highways.”
“I think the positive effect is we’re able to provide an adequate level of service and provide safety to the traveling public,” Juelfs says. “That’s certainly on the forefront and has to be balanced with environmental stewardship, as well.”
Rivertop’s Dave Wilkening says the industry is responding to the needs of the pacific northwest states. He hopes it spread. “The trend in the industry,” he says, “is to do when possible ‘green chemistry.’ There’s a lot of momentum behind that.”
Wilkening says the East coast and Midwestern states that use a lot of solid salt are beginning to adopt liquid de-icers, but still haven’t fully embraced anti-corrosion inhibitors.
“But there’s a growing understanding that corrosion is a large expense,” Wilkening says. “For example, a bridge deck costs multi-millions of dollars. So if you can reduce that by reducing the corrosive effects of de-icing salts you’ve saved the taxpayers millions of dollars in replacement fees just by increasing the service life of bridge decks, equipment, guard rails, signage.”
Wilkening says while that might be hard to quantify because of the long-term effect, there’s a growing awareness that you need to consider those things in the overall costs of a road maintenance program.