The USS Grampus (SS-523), a Tench-class submarine, was laid down on 8 February 1944 at Boston Navy Yard and launched on 16 December 1944. The USS Grampus (SS-523) served as a prototype for the GUPPY submarines, including numerous characteristics that would later emerge aboard nuclear submarines, due to the innovative snorkeling equipment that allowed it to stay underwater for far longer durations than the World War II fleet submarines. The USS Grampus (SS-523) was decommissioned and struck from the Naval Vessel Register on 13 May 1972, and sold under the Security Assistance Program to Brazil, where was renamed Rio Grande do Sul (S-11). After six years of service, it was decommissioned on 16 November 1978 and scrapped on 18 June 1981. Navy veterans are at the greatest risk of developing asbestos-related diseases. Although the Navy stopped filling Navy vessels with asbestos in the 1970s, the vessels that did contain asbestos remained in service for many years after manufacturing ceased. Because of the many applications for asbestos aboard ships, as well as the tight confines, Navy personnel were frequently exposed to asbestos fibers. Navy veterans affected by asbestos exposure may be eligible for disability benefits through the U.S. Department of Veterans Affairs.