At noon on Monday, snowboarder Mark Bauhs, 15, was eight feet above the snow after launching off a jump in the Boreal terrain park. Seconds later, he was back on the snow in a lot of pain - the result of a bad landing that left him with a fractured radius in his forearm and a lot of explaining to do to his volleyball coach.Two hours later, his became the first signature to go up on the Tahoe Forest Hospital's 2003-04 Wrist Fracture Hall of Fame.Bauhs, a Junior Olympic-caliber volleyball player from the Bay area, was on a trip with …