The decommissioning of the Taiwan Research Reactor (TRR) is the first large-scale nuclear reactor decommissioning project in Taiwan. The TRR underground dry storage facility (DSP) provides a storage site for spent nuclear fuel from the TRR. However, after many years of operation and waste disposal, the surface structure, soil and interior of the storage pits have become radioactively contaminated. According to the decommissioning plan for the TRR, all contaminated waste in the storage pit area must be removed. NARI has independently developed a removal method and waste management technology as described below:
(1) The design and development of the removal equipment: Given the challenging circumstances of the waste being located underground, including 175 storage pits and the soil between the storage pits, which are up to 5 m deep, and the distance between the storage pits being only 60 cm, the specifications and work methods were necessarily restricted. The removal process involved the use of circular saws for cutting, electric excavators for soil removal, drilling equipment for structure separation, and a double winch for lifting and removing the storage pits. This approach not only reduced the radiation operation time but also enhanced safety.
(2) Waste measurement technology: NARI has developed a rapid screening technology for measuring radioactive waste and constructed equipment for detecting soil and concrete waste. Once calibrated and tested, the system can rapidly and accurately measure the activity concentration of waste, thereby improving processing efficiency.
The waste management system: A waste management information system has been implemented to integrate measurement data and radiation protection information. The system offers automatic feedback, real-time query and APP operation functions, providing an effective solution for waste management and enhancing operational safety.

To overcome the difficulties of removing underground dry fuel storage facilities, it is essential to consider the space limitations of the plant, ensure the safety and protection of workers operating on the ground, develop storage pit removal technology, build waste measurement technology and develop an information management system, and study the optimal operating conditions. The key technical application results are described below:
(1)  In light of the considerable depth of the 175 storage pits (5 m below ground level) and their location in a radiation-controlled area, it is vital to consider factors such as personnel safety and radiation contamination dispersion. In view of the limited space on the site, NARI has developed the removal equipment required for each stage of DSP removal. An automatic circular saw is utilized to cut through the upper concrete layer, which has the dual benefit of reducing the time for personnel required to spend at the site for the duration of the operation and minimizing the overall time spent on-site. Furthermore, the use of a remote-controlled electric excavator with a modified arm and bucket allows us to complete the soil excavation between the storage pits, thereby reducing the time spent on-site. Subsequently, drilling equipment is utilized to operate the machinery remotely above ground, with the objective of separating the underground concrete layer structure. The mobile platform and fixed crane with double winches represent a significant improvement in radiation protection. They enable the safe and effective storage, lifting and moving of storage pits, reducing the radiation operation time and enhancing the safety of personnel and waste disposal. In line with the principle of radiation protection "ALARA", this technology significantly enhances the safety of the radiation environment.
(2)  To ensure effective waste management and compliance with regulations, NARI has developed a technology for measuring and screening radioactive waste, constructed equipment for measuring and detecting soil and concrete waste, and applied the Institute's own calibration source (caesium-137) to calibrate the system. NARI has also conducted tests on measurement distances, contamination shapes, and system stability, which have been validated through on-site sample simulation tests. The design meets all the required specifications. The equipment boasts automatic positioning, rapid operation and a brief measurement time, enabling precise activity concentration readings and enhanced waste treatment efficiency. It also facilitates the implementation of measures to reduce waste capacity and volume. Furthermore, the source coding of waste allows the system to record the source information of the tested material during the measurement process.
The substantial volume of data produced from waste measurement and classification is managed through the Waste Management Information System. The system offers a solution to the complexity of records, effective waste data management and traceability. The system offers a range of functions, including automatic return of measurement data, real-time query, information management of the warehouse and convenient control through the app, which collectively enhance the efficiency of waste management. 

Unlike general dismantling operations, decommissioning project management focuses on radiation safety and waste management in addition to general industrial safety management. Therefore, NARI can participate in the decommissioning project of the domestic nuclear power plant after completion of the removal of the TRR underground fuel dry storage facility (DSP), by using its accumulated technology and experience in project management and waste management to assist in radiation protection and waste management. This will contribute to the localization of decommissioning technology in the future.