The new buildings at One World Trade
Center are being built with green concrete.
This post provides highlights from a session of The CR CommitForum, held earlier this week in New York City. Find a mistake in the text? Write us here to share the correction.
Michael Gentoso, VP, Atlantic Region, US Concrete
David Green, Eco-Efficiency Analyst, BASF Corporation
Durability From the Ground Up
On September 11, 2011, many of us turned to our televisions to watch the memorial ceremonies at the World Trade Center complex. While our eyes were drawn to the waterfall and the stunning new building, we may not have noticed the miles of new concrete that fill the area. When complete, Towers 1, 2, and 3, the transportation hub, and the museum and memorial will have close to a total of 1 million yards of concrete.
Sustainability experts, however, paid attention. One World Trade Center is being built from the ground up with Green Concrete, a new material for reducing landfill waste and improving a building’s carbon footprint.
Cement, the powder we combine with stone, sand, water and other elements to make concrete, is one of the world’s leading contributors of carbon dioxide to the environment. Replacing cement with other materials – especially recycled materials that otherwise would have been hauled to a landfill – is one of the building industry’s growing strategies for being more sustainable.
Green Concrete uses fly ash (a byproduct of burning coal) and slag (a byproduct of steel manufacturing) to replace cement.
“This is the most effective means of reducing carbon dioxide emissions in our industry,” said Michael Gentoso, VP of US Concrete. “For every ton of cement we take out of our mixes, we’re saving a ton of carbon dioxide in our atmosphere.”
“It’s our responsibility to seek smarter ways to protect our environment,” says Gentoso.
At One World Trade Center, the use of Green Concrete saved 12 million pounds of carbon dioxide emissions, 8 million kWh of energy, and 30,000 gallons of fresh water. US Concrete used up to 70% replacement materials in the One World Trade Center mix.
Elsewhere government agencies are beginning to encourage the use of replacement mixes in concrete. The California Department of Transportation requires a minimum of 25% replacement materials in their construction work. As a result the Oakland Bay Bridge is being rebuilt with Green Concrete, in mixes as high as 60% replacement materials.
BASF contributes to US Concrete’s green concrete efforts by providing an eco-efficiency analysis that considers the life-cycle costs of a product, including its toxicity levels, to understand the human impact of a project.
(Note: the EPA does have restrictions on the use of fly ash. A web search of “EPA fly ash” will provide you with additional details.)
Move beyond greening to a place where sustainability drives innovation. Join our Senior Executive Roundtable with business sustainability pioneer Stu Hart, on Friday, Oct. 14th. More information at www.cvdl.org/roundtable.
For more details on the Center for Values-Driven Leadership, visit our web site, www.cvdl.org.