The process included lower faces and digging up bunkers so that they cut up into greensites instead of resting above them. New sand and drainage were also part of the project, as were efforts to enable easier access into the bunkers. Here is a video (slightly larger version at Vimeo) demonstrating the before/after views of the holes:

La Cumbre Country Club Bunker Renovation from Geoff Shackelford on Vimeo.