Volunteers with Pacific Northwest Search and Rescue will conduct training at Multnomah Falls on Sunday.  As a safety precaution, the Larch Mountain Trail, from the plaza to the top of the falls, will be closed on Sunday from 6 a.m. until midafternoon.  The all-volunteer search and rescue team will practice rope and rescue skills on the steep slopes, while also removing trash from hard-to-reach areas around the falls.  Forest Service officials say the work will help keep the popular recreation site clean and safe for visitors.  Pacific Northwest Search and Rescue provides ground search and rescue resources to agencies across the region.  Team members train regularly and remain on call around the clock.