A proposal to impose limits on chemical de-icers used on Montana’s highways is headed to the Senate floor after getting the green light Wednesday from the Senate Finance and Claims Committee.

The bill initially passed the Senate Highways and Transportation Committee on Tuesday by a 7-5 vote, and was referred to the finance committee during Wednesday’s morning floor session.

State Sen. Dee Brown, R-Hungry Horse, is sponsoring Senate Bill 369, which would bring down the amount of liquid chloride-based chemicals, such as sodium chloride and magnesium chloride, used on state roads over several years. Environmentalists voiced concerns about the chemicals, which ultimately can wind up in rivers and creeks.

During her testimony Wednesday, Brown said that the use of those chemicals increased six-fold over seven years, and in 2013 totaled more than 80 pounds of salt per mile of roadway receiving the treatment.

Brown said the state used 6 million gallons of salt brine in 2014, compared to just over 1 million gallons in 2007.

Amy Seaman, a Montana Audubon spokeswoman, admitted that little is known about how the road chemicals impact the environment, but said she was still concerned with the increasing rate at which the department uses them.

“Chloride doesn’t naturally filter out through soils or groundwater bodies, so it actually can move completely through groundwater into injection wells, where you might have drinking water coming out, or back into surface waters.”

However, Jon Swartz, a spokesman for the Montana Department of Transportation, warned the bill would prove costly to the state and require higher volumes of sand and rock salt on the roads.

“Current level of service could not be sustained and we would likely revert back to how events were managed over 30 years ago, which would result in increased snowpack and ice on our Montana highways for longer periods of time during the winter,” Swartz said.

Explaining his “nay” vote, Sen. Eric Moore, R-Miles City, also noted safety concerns.

“I’ve driven too many trucks on icy roads,” he said. “If this is going to compromise safety on icy roads, I don’t think it’s worth the cost.” 

Under the proposed law, chloride chemical road treatment would be limited to Dec. 1 through March 31 each year. Those chloride-containing chemicals, including road salt, would be phased down over up to 10 years, with 10 percent reductions mandated each year until the amount being used is equal to the average amount from Dec. 1, 2007, through March 31, 2010. The bill would not apply to sand with 10 percent rock salt.

Brown noted that she introduced a bill during the 2013 session that would have completely banned the use of the liquid de-icers, but the $29 million price tag for the highway department was too prohibitive. The fiscal note for the current bill estimates an annual cost between $8 million and $10 million.

Responding to concerns about the chemicals’ effect on vehicles, Swartz said a corrosion inhibitor is added to reduce property damage.

“I don’t care if you’re putting an inhibitor in it. It isn’t good for our environment,” Brown responded.

The bill passed the finance committee 13-6, sending it back to the full Senate just ahead of Friday’s deadline by which bills must pass at least one chamber of the Legislature.

Reporter Samuel Wilson can be reached at 751-4407 or by email at swilson@dailyinterlake.com