Yes, every last bit of anything that wasn't there before Burning Man will be removed. A cleanup crew literally sweeps the entire area in a very fine grid pattern and cleans up every last bit...even picking up sequins with tweezers. A truly amazing effort IMO. I haven't found a report for this year's event (the cleanup is probably still under way) but you can learn about the details of the Afterburn efforts in previous years here: http://afterburn.burningman.com, and specifically about last year's cleanup effort here: http://afterburn.burningman.com/06/dpw/setup_cleanup.html
--C

Energy consultant, writer, blogger www.getreallist.com

It should now be called Suburban Man----
We have come a long way from Baker Beach.