Nearly 4,000 oil and gas structures currently exist in Federal waters of the U.S.outer continental shelf (OCS), with the vast majority present in the Gulf of Mexico. The primary purpose of these structures (e.g., fixed platforms) is to develop and produce oil, natural gas, and gas condensates from offshore hydrocarbon reservoirs. When offshoreproduction from a producing field becomes uneconomic, the lease(s) may be terminatedby the operator. As one of its lease conditions, the Minerals Management Service(MMS) requires that operators (responsible for installation and operation of a platform)subsequently remove the structure within a year of lease termination