According to TEPCO’s storage management plan, secondary wastes from water treatment stored in adsorption towers that contain large amounts of radioactivity will be prioritized for storage in the building.

For the secondary waste generated from contaminated water treatment, a large waste storage facility is under construction as a storage facility for adsorption towers and the like. In addition, the ALPS slurry generated from the multi-nuclide removal system, etc., which has high water content rate and is fluid, will be stabilized (dehydrated) (treatment facilities to be installed in FY2026)), and the sludge from the decontamination system will be transferred to a storage facility on higher ground (collection to be started in FY2025).

Considering the radiation effects of the slurry, the transfer of slurry from the HIC, whose integrity cannot be confirmed in the event of a fall, is being conducted with the aim of completing the transfer before the start of operation of the slurry stabilization treatment facility.

At the Radioactive Material Analysis and Research Facility Laboratory-1, efforts are being made to use analytical methods to obtain data easily and quickly as a standard analytical method.

In order to obtain analytical data on high-dose waste, on-site demonstration of a technology for collecting adsorbent material from cesium adsorption vessels is being conducted.

As a countermeasure against hydrogen generation during storage of high-dose waste, factors (hydrogen embrittlement, radiation degradation, etc.) affecting filter degradation (blockage, damage, etc.) and methods to confirm these factors have been investigated.

From the perspective of treatment, the low-temperature treatment technology is undergoing full-scale testing to confirm the prospects for application in actual facilities, meanwhile, further investigation of solidification feasibility testing methods and evaluation methods for the stability (leaching characteristics, long-term alteration phenomena, radiation effects, etc.) of solidified products produced by various treatment technologies are also being studied. In addition, the intermediate treatment technologies such as pyrolysis treatment, the confirmation of those technologies to detoxification of organic matter and inactivation of reactive and corrosive substances has been initiated.

For disposal, a survey of the necessary information and knowledge about waste which is being considered in the waste streams is being conducted in order to build measures to address the needs required for the disposal concept, meanwhile, the establishment of storyboards on the progress of key events at disposal facilities have been initiated.

Detailed visual inspection outside the pedestal, sediment thickness measurements, sediment debris detection and evaluation (neutron flux level, etc.), and sediment 3D mapping measurements are being conducted as part of the Unit 1 PCV interior investigation. The sediments have been successfully sampled and will be analyzed in the future. In March 2023, an underwater ROV successfully entered the pedestal for the first time, and much information was obtained on the state of concrete loss at the bottom of the pedestal, sediments and fallen objects at the bottom of the pedestal, and upper structures such as the control rod drive mechanism housing.