In the ThorCon system, no complex repairs are attempted on site. Everything in the fission island except the hull itself is replaceable with little or no interruption in power output. Rather than attempt to build components that last 40 or more years in an extremely harsh environment with nil maintenance, ThorCon is designed to have all key parts regularly replaced.
Up to 50 ThorCon plants are supported by a Centralized Recycling Facility (CRF) and a separate Fuel Handling Facility (FHF). Normally, the Cans are changed out every four years. When the Cans need replacing, they are shipped to the CRF in a special purpose Canship. The video above shows a Can being transferred to the Canship. At the CRF, the Cans are disassembled, cleaned, inspected, and worn parts replaced. The problems of decontamination and waste disposal are shifted from the plant to this facility.
This system of regular replacement of the most critical components means that major upgrades can be accomplished without significantly disrupting power generation. And since the returned Cans are disassembled and fully inspected, incipient problems will be caught before they can turn into casualties.
Such renewable plants can operate indefinitely; but if a ThorCon is decommissioned the process is little more than pulling out but not replacing all the replaceable parts.