June 19, 1969 The summer season on the beaches begins this Saturday, and today city lifeguards were nearing the end of a training program for thirty-five lifeguard trainees. About a dozen will be selected from the thirty-five hopefuls for summer jobs on the beaches to bring the total number of lifeguards to 120. Today's exercise at Casa Pool and Boomer Beach in La Jolla involved the use of a land line -- a long reel of rope carried from the beach to the victim so he can be towed ashore. Lifeguards have to be 18 years of age, good swimmer, high school graduates and satisfactorily complete a practical and written exam.