Interesting info TC. So they should have been re-applying epoxy periodically....didn't know that. It's tough on the feet when pebbles start coming apart, gotta get this resolved!
Someone clearly spent a good chunk of change or had friends in the business because there's well over 1,000 sq ft. of total pebble tec coverage between the paths, hot tub area, and covered patio.
Some good reading here:
http://www.epoxyproducts.com/riverstone.html