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Green thumb
Green thumb
Several lush gardens will be irrigated with the headquarters building's wastewater. The plants and trees help keep the environment cool and absorb carbon dioxide.

NEXT: A clean ride
Last updated December 03 2008: 10:34 AM ET
Eco-friendly city of the future The Emirate of Abu Dhabi begins construction on its green city, Masdar. See the plans for this $15 billion undertaking. More video