LEED certification applies to not only how a building is built, but also how that green space is maintained. Once a building has been granted LEED certification there are certain maintenance requirements that have to be upheld under the LEED certification guidelines. The link below details all of these maintenance requirements. Turn to page 110 for specific details about the required low-environmental impact cleaning and maintenance of these buildings.
http://www.usgbc.org/Docs/LEEDdocs/EB-final%20content%20version.pdf