In Hopes of Early Decontamination - AESJ Clean-Up Subcommittee s Activities -

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1 In Hopes of Early Decontamination - AESJ Clean-Up Subcommittee s Activities - February 4, 2012 Tadashi Inoue Clean-Up Subcommittee Chair (Fukushima Decontamination Advisor)

2 Activities of Clean-Up Subcommittee Proposal to set up an environmental monitoring center and an environmental remediation center Production of a catalog of environmental remediation technologies and its supplement Produced a list of applicable remediation technologies. Evaluated findings on domestic and overseas remediation technologies and incorporated them into the catalog. Presented the catalog to central and local governments responsible for environmental remediation. Analysis of environmental remediation strategies, scenarios and technologies EURANOS: Analysis of environmental remediation technologies based on the case in the Chernobyl accident and description of their features (carried out with an EU fund) Demonstration of remediation technologies Example: Bench-scale testing of rice field-puddling technology Communication with local communities Essential for developing a remediation plan and selecting remediation technology The AESJ, as a group of experts, bridges the Central Government with local governments and communities. Held a Safe and Security Forum with Fukushima Prefecture. 2

3 4 Proposals for Remediation Proposal 1: Set up an Environmental Radiation Monitoring Center and an Environmental Remediation Center at the earliest possible time. Proposal 2: Develop environmental remediation strategies for removal of radioactive materials. Proposal 3: Present an environmental remediation program at the earliest possible time. Proposal 4: Have the local community involved in activities. 3

4 Example of Rice Field Puddling Demonstration Radiation measurement after draining the field Soil sampling after draining the field In the first step, the weeds were removed. After removal of weeds with high Cs concentrations, the surface soil was plowed along with the root of the weeds. [Radiation dose rate (provisional data) at 1 cm height Before plowing: micro Sv After plowing: After rough puddling: NaI detector (w/ a 3.5 cm lead shield) The radiation level of the first water introduced into the field should be checked. Water source 3. Radiation measurements of water (1) Cs-137 concentration in water Rice field water Rice field water Rice field water Before After draining/ After After draining/ Because the accumulated radioactive materials (in the mud and moss, etc.) were washed away. 4

5 Process for Return Home of Residents & Its Key Points 1. Produce a detailed contamination map m mesh map Search for hot spots in the map 2. Set a target dose. (Realistic target level for early return home) A realistic target level is 5 to 10 msv. Example:5 msv Achieve 1 msv as a medium-term target. Determine the target through communication with the residents. 3. Provide a temporary storage facility in each area. (From on-site (pretemporary) storage to temporary storage) Provide a storage facility in the village. (Communication and agreement with the residents is essential.) A temporary storage facility must be determined to start decontamination operations. 4. Develop decontamination and implementation plans. (Reflection of the desire of the residents and agreement with the residents) Decontamination plan (including the budget): previously mentioned submission to the Government and the Prefecture (apply for a budget) Implementation plan: Priority in decontamination according to the contamination map, lifestyle and production activities; public facilities such as schools Cooperation and advice from experts are essential. 5. Perform decontamination operations. (The presence of experts is important.) Decontamination operations by individuals or companies Reference to a decontamination manual Decontamination operations in the presence of experts 6. Return home 5

6 Wrap-Up Set a realistic target decontamination level to start full-scale decontamination operations at the earliest possible time. Everything, including houses, housing land, agricultural land and forests, must be decontaminated. (Change from scattered to integrated government services) Expectations on the Office of Fukushima Environmental Restoration 6