On any given evening, Nixon Field hums with the shouts of rugby players practising a lineout or the sounds of intramural athletes’ laughter echoing through the night air. The patch of green beside Kingston Hall is the home turf of the multi-championship-winning Gaels rugby teams, and of intramural flag football and ultimate frisbee leagues. Nixon Field has been a gathering place for the Queen’s community since the earliest days of the university. And this green space at the heart of campus recently got a climate-friendly makeover.
The new Nixon Field has an innovative Field Turf surface that removes carbon dioxide from the atmosphere. The design uses a mineral called wollastonite, mined at the Canadian Wollastonite mine about 35 kilometres northeast of Kingston. Wollastonite naturally absorbs carbon through a process known as enhanced rock weathering. Carbon in the air chemically bonds to it and attaches permanently to the wollastonite. Over its 10-year lifespan, Nixon Field’s new surface will absorb about as much carbon as 12 acres of forest.
“Wollastonite naturally absorbs carbon dioxide, and when you pulverize it, more of the mineral is exposed to the air, and it absorbs dramatically more carbon dioxide,” says Warren Mabee, Director of the Queen’s Institute for Energy and Environmental Policy.
To maximize Nixon Field’s carbon sequestration potential, a thin layer of wollastonite dust was included in the field’s infill layer — the materials below the turf that act as a cushion for the field above. At a glance, the new Nixon Field looks no different than any other but, below the surface, the wollastonite gradually draws carbon out of the atmosphere – a bit like an invisible forest.
“You need an open area to do this, and wollastonite is sometimes spread on large warehouse roofs to absorb carbon,” says Dr. Mabee. “When it is spread thin, more of the mineral is exposed to the air, so there are more chemical bond sites for carbon to attach to. Nixon Field is a great place for this because it is right in the middle of the city. So, it absorbs carbon emissions essentially at their point of origin.”
Over the coming decade, it’s estimated the new Nixon Field will absorb about as much carbon as 165 trees. But this partnership between Queen’s, FieldTurf, and Canadian Wollastonite will put more concrete numbers to the design’s capabilities. Queen’s researchers will undertake a long-term study to quantify how much carbon is sequestered.
“This is a great opportunity to put this technology to work and see if it can deliver what it promises,” says Dr. Mabee. “Wollastonite is not a super expensive material, and it doesn’t require a lot of engineering to do this. It’s a great opportunity to demonstrate a new technology.”
