Cement is one of the most ubiquitous and GHG-intensive construction supplies used in the world. Nearly every structure, whether it is a barn or a skyscraper, contains concrete. Nearly three tons of concrete are used annually for each man, woman and child. Few people, however, even those in the construction industry, are aware of concrete’s huge environmental impact.
By most estimates, concrete production accounts for 5% of total man-made GHG emissions.
According to the EPA, cement production in the United States emits large amounts of mercury, hydrochloric acid, hydrocarbons and soot. Not to mention, the cement industry is the fourth-largest emitter of mercury in the United States.
Huge amounts of energy are needed to produce cement, partly because of the extreme temperatures (as high as 1,450 Celsius) needed to bake the limestone in a kiln, which is one of the first stages of the post-extraction process.
Other stages in production can be equally harmful to the environment. Standard cement is made up of limestone and other materials like clay which must be extracted from quarries, each of which can have a devastating impact on landscapes.
Employee health and safety is also a huge concern for companies. The concrete industry’s accident and injury risk is higher than others such as petrochemical and petroleum refinery industries, according to their own admissions. Many aspects of cement production are inherently dangerous, but improvements can be made.
Although the object of my post is to highlight the negative environmental impacts of the concrete industry, cement is sustainable in many ways. The environmental benefits of concrete range from strength and durability, versatility, low maintenance, affordability, and fire-resistance to excellent thermal mass, locally produced and used, and albedo effect. For more information on concrete’s “sustainability” visit WBCSD.
Luckily the trust World Business Council for Sustainable Development has created the Cement Sustainability Initiative (CSI), an effort to reduce the harmful environmental impacts of the worldwide cement industry by enlisting some of the world’s biggest concrete companies.
The CSI began in 1999 when ten of the world’s biggest concrete companies joined together to “pave way for a more sustainable cement industry.” Since its inception, the initiative has successfully developed best practice plans and carbon accounting standards for the international cement industry.
Once companies join the initiative they are given four years to complete the requirements outlined in the CSI’s charter. The charter includes six sections: C02 and climate change, responsible use of fuels, employee health and safety, emissions reductions, local impacts on lands and communities, and reporting and communications.
Just to give you an idea of what each section entails, the three requirements under the CO2 and Climate Change section are mandatory public disclosure of GHG emissions, development of emissions mitigation strategy, and annual reporting of emissions. As the list above shows though, the initiative takes into account everything from GHG emissions and the health of employees, which are not given preference by the CSI.
The CSI has created a Health and Safety task force that will tackle employee concerns and attempt to streamline the way the cement industry reports their accidents and injuries. Despite its successes, the concrete industry still has a long way to go to consider itself “sustainable.”
For more information, go to: wbcsdcement.org.