EMPLOYEE WAS TAKING DOOR OFF OF SAND TANK AT LOWER LOADING. THE DOOR CAME OFF AND SOME WATER CAME OUT THE EMPLOYEE JUMPED BACK TO KEEP FROM GETTING WET TO PULLED MUSCLE IN LOWER BACK AREA. E MPLOYEE WENT ON VACATION THE NEXT DAY AND DID NOT WANT TO GO TO THE DR EMPLOYEE CAME BACK FROM VACATION AFTER A WEEK OFF.