Do it ASAP

Ben, aged 72, continues to work an eight-hour day at a large corporation. He is in frail health and was off work for an extended period of time when he had heart surgery. He enjoys collecting his full Social Security check as well as the corporate check. Unfortunately, he falls asleep at his desk and sleeps for many hours during the day. Other employees notice and resent this behavior. What employment laws apply here? What is a good business decision for Ben's manager