EE was descending from haul truck. EE continued to try and descend with lunch box in one hand and the seat cushion in the other, while holding handrail. EE slipped on the last step and fell approximately 30"" to the ground, landing on back side. EE didn't wish to see a doctor until the following Tuesday (10/18) EE was put on light duty and went on vacation effective 10/19/16.