Apple's enormous Campus 2 building site in Cupertino, CA, has been pretty much off limits since construction began (excepting hard-to-restrict aerial photography), but San Francisco public radio station KQED got a quick on-the-ground tour of the site which, well, it's very much a construction site right now. Lots of concrete and steel and whatnot, just arranged in the ring of the Apple Campus 2 design instead of more traditional right-angled structures.
The new complex is being built on a former HP campus site. Said KQED's Amy Standen:
"What Apple inherited on the property was several older buildings, all of which were broken down and deconstructed. Much of the material from those old buildings was recycled into new building material to make the new campus, according to Apple."
Apparently 95% of the debris from the old buildings is being recycled and will be reincorporated into the new structures. The prodigious use of on-site recycled materials means that Apple's reduced the impact of the construction on the surrounding community — nowhere near as many concrete trucks have been rumbling through Cuptertino to pour the building's enormous foundation and subterranean parking structure, for example.