IE was walking leaving Unit 2 RM 1 and was struck by rock that fell from the roof. Small pieces fell first, then a piece measuring (3'.5"" L x 2'.2"" W x 4' T) struck EE in the hip area. The ER X-rays were negative, and IE was released to work as tolerated. A follow up MRI showed a closed stress fracture of left inferior pubic ramus of the pelvis.