EE WAS RIDING MANTRIP TO SECTION FROM SURFACE. MANTRIP RAN OVER A PIECE OF ROCK. MANTRIP BOUNCED AND JARRED HIS BACK WHCIH RESULTED IN PAIN LATER THAT DAY. CALLED IN 2/17/05 INFORMING ME ABOUT ACCIDENT, SAID EE WAS GOING TO HAVE BACK CHECKED AT HOSPITAL