Two trails actually; one for peds and one for bikes. the one for peds is singletrack the other for bikes is an old double track that is now in most places a wide single track. This trail is always steep up or down and always rocky
From 32nd turn West and go dowm two or three blocks until the road dead ends turn right and follow the road until pavement ends. From there it's pretty obvious where the trail is.
http://www.singletracks.com/item.php?c=1&i=3397