Not sure who put the anchor there, but there is as of 4/21/07 a rap station less than half a rope length up from the terrace belay so that you can rap back down to the terrace and not have to walk up and around to get off the climb.
edit-
http://www.stanford.edu/~clint/pin/flumes.htmjust after the last bolt shown on the route in this topo. Route # 289a.