Unintentional roof fall discovered while traveling return airway. Fall pulled 4 roof bolts. Top previously supported with 6' full grout resin bolts. Area mined at or about 1/15/07. Fall measured approximately 6'HX15'LX17'W. Fall location: 11 Belt, 19 Block, 3 Hdg. No injuries or property damage. Investigated by T. Smallridge, WVMHS&T and J. Lyll, MSHA.