A Non-Injury Roof Fall occurred in the Pillar Line on the MMU. 003-0 Section on the 1 Rt. Panel off the 1 North Submains. A section of the mine roof approximately 20' long x 4' thick set down on the No. 1 Mobile Roof Support while the continuous miner was cutting the No. 3 Pillar Block on the run No. 3 between X-cut # 20 and X-cut # 21. ( MSHA was immediately notified.)