High-Level Waste (HLW) refers to highly radioactive materials that result from the reprocessing of spent nuclear fuel or from the production of nuclear weapons. This waste generates significant heat and radiation, requiring careful handling and long-term storage solutions to protect human health and the environment. HLW is typically stored in specialized containers and facilities designed to contain radiation and prevent leaks. The management of HLW is a critical aspect of nuclear energy and waste disposal, involving regulatory oversight and advanced technology to ensure safety. Long-term disposal solutions often include deep geological repositories, where waste can be isolated for thousands of years.