MAN KILLS SELF SLIDING DOWN MOUNTAIN ON FOAM PAD (A.P. Mammoth Lakes) A San Anselmo man died yesterday when he hit a lift tower at the Mammoth Mountain ski area while riding down the slope on a foam pad, authorities said. Matthew David Hubal,22, was pronounced dead at Centinela Mammoth Hospital. The accident occurred at about 3:00 AM, the Mono County Sheriff's Department said. Hubal and his friends apparentlyhad hiked up a ski run called Stump Alley and undid some yellow foam protectors from the lift towers. The pads are used to protect skierswho might hit the towers. The group apparently used the pads to slide down the ski slope and Hubal crashed into a tower. It was not known if the tower he hit was one with it's pad removed.