​New UVM task force aims to reduce road salt on campus

Vermont Business Magazine A group of faculty, staff and students at the University of Vermont has been studying the negative impacts of road salt on campus and exploring ways to reduce its use.

“Making sure pedestrians on campus are safe while being cognizant about environmental damage salt causes is a delicate balance,” said Lynn Wood ’20, physical plant facilities manager at UVM.

Professionals charged with applying salt where it is needed at UVM have continued to introduce new materials and methods to reduce usage. Matt Walker, grounds manager for the physical plant department, has been experimenting with the use of magnesium chloride, an anti-icing liquid which helps break the molecular bond between ice and paved surfaces and makes cleanup more efficient. The department had previously used rock salt for this purpose.

Among the solutions being explored by the university’s Salt Mitigation Task Force is new equipment and technology with potential to reduce salt consumption. An especially equipped truck is being tested this winter. It can distribute both a liquid de-icing agent and rock salt on walkways. Spreading of either product can be pre-programmed using geo-tracking software. “It helps take a lot of the guesswork out of the equation,” Walker said.

Application of road salt, even on newer infrastructure on campus, can cause steel doors and frames to rust prematurely, concrete sidewalks and stairs to crack, and mortar in brick and stone structures to corrode.

And that’s just the above ground infrastructure. Salt also can eat away at underground utility vaults, concrete chambers that house valves and other key components that deliver steam to campus buildings. Kevin Sweeney, UVM’s deferred maintenance project manager, has the tricky job of keeping systems running while repairing vault damage.

He noted that rebuilding and waterproofing a utility vault near the University Heights complex recently cost $167,000. “We ended up increasing the elevation of the vault and bringing the vents above grade so runoff into vault wouldn’t be an issue,” Sweeney said.

As any UVM chemistry student can tell you, salt and concrete just don’t mix. Calcium hydroxide present in concrete reacts with the calcium chloride in salt, creating calcium oxychloride. When forming inside concrete, calcium oxychloride crystals expand, causing internal cracks and crumbling.

Still, salt is a natural solution for preventing accidents in wintery weather. Salt lowers the freezing temperature of water, preventing ice from forming. The problem is that salt not only damages buildings but contaminates drinking water, kills plants, reduces soil permeability and damages freshwater ecosystems.

Associate professor Kristine Stepenuck, extension program leader for Lake Champlain Sea Grant, has dedicated her career to understanding human impacts on freshwater resources. She’s explored the history of using salt as a melting agent since the early 1940s when salt was first used by the New Hampshire Department of Transportation.

“At that time about 5000 tons of salt were used per year in U.S.,” she said. “Fast forward to 2015, about 20 million metric tons of salt were used each year.”

How much is that? Stepenuck provides this illustration: “If each salt truck holds 10 tons of salt, 120 million metric tons would create a traffic jam of salt trucks from Burlington to Seattle, back to Burlington, and back again as far as Glacier National Park.”

Funding for the task force’s work comes from UVM’s Sustainable Campus Fund (SCF), which supports proposals aimed at improving campus sustainability. The SCF is funded through a $10 per semester student fee, so projects are essentially supported by the entire student body.

College of Engineering and Mathematical Sciences (CEMS) senior lecturer John Lens led a student project last year in conjunction with physical plant employees. An undergraduate intern in the civil and environmental engineering program documented salt damage to exposed steel and concrete structures across campus. Lens and Courtney Giles, lecturer in civil and environmental engineering and director of Curricular Enrichment in CEMS, are also planning on detailed chemical analyses of de-icing salts used on campus to identify specific trace constituents potentially more harmful to infrastructure and the environment.

“Ultimately the material engineering aspects of our work will hopefully lead to design recommendations for new structures we build,” Lens said.

And, through an REU (Research Experience for Undergraduates), environmental engineering

students have been working for the past nine months to collect and analyze samples from five of UVM’s containment ponds. The data they collect will serve as a baseline as the Task Force continues to explore solutions. Student researchers don’t yet have a full year of data—they will continue to take measurements through the summer to complete the baseline.

Robby Tschiember, one of the students collecting water samples, is gratified that the work he’s doing is more than just an academic exercise. “It’s great to be able to do this along with faculty advisors who are showing me the ropes of how research works and how it can have real outcomes.”

Likewise, Liza Mclatchy, another one of the students, knows the work she’s doing will result in real-world benefits. “I know the work I’m doing is going to make an impact on the Burlington community. It makes me feel like it’s part of something bigger than me. It’s not just a job—it’s way more than that.”

Since 1791, the University of Vermont has worked to move humankind forward. UVM’s strengths align with the most pressing needs of our time: the health of our societies and the health of our environment. Our size—large enough to offer a breadth of ideas, resources, and opportunities, yet intimate enough to enable close faculty-student mentorship across all levels of study—allows us to pursue these interconnected issues through cross-disciplinary research and collaboration. Providing an unparalleled educational experience for our students, and ensuring their success, are at the core of what we do. As one of the nation’s first land grant universities, UVM advances Vermont and the broader society through the discovery and application of new knowledge.