AN UNINTENTIONAL ROOF FALL OCCURRED IN #8 RETURN ENTRY 2 X-CUTS OUTBY SURVEY SPAD #277; THE FALL MEASURED APPROX. 20' W, 40' L, 8' HIGH. THIS AREA HAS BEEN EXPERIENCING ADVERSE ROOF CONDITION S (SLICKEN SIDED STRATA); AREA WAS SUPPORTED WITH A 6' POINT ANCHOR AND 8' #804 BOLTS.