Proposal to conduct a “July dry run” to prepare for the Nankai Trough Earthquake

1. Purpose of the Proposal
This proposal envisions the massive damage caused by a Nankai Trough earthquake, and proposes that July 2025 be designated as a “dry run month” in which the government, local governments, and citizens work together to implement disaster prevention actions.

 

2. Background and Issues

• The government’s damage estimate predicts a tsunami of over 10 meters along the Pacific coast from Shizuoka to Miyazaki prefectures. (NHK [1])
• According to the Cabinet Office, the focal region of the Nankai Trough earthquake includes a wide area south of the Median Tectonic Line. This region is highly likely to experience a large earthquake directly beneath it. (Cabinet Office [2])
• Manga artist Ryo Tatsuki has publicly announced a prophetic dream about a “huge tsunami in July 2025,” and her past predictions of earthquakes have also come true.
• As for nuclear power plants, one reactor is still in operation at the Ikata Nuclear Power Plant (located on the Median Tectonic Line). In addition, a total of 1,900 tons of spent nuclear fuel is stored at the Ikata Nuclear Power Plant and the Hamaoka Nuclear Power Plant (located on the boundary between three plates). Both nuclear power plants are located in the epicenter of the Nankai Trough earthquake, and due to their geographical characteristics of being on the Median Tectonic Line and on the boundary between three plates, strong shaking is expected that far exceeds the seismic limit of 1,000 gals for nuclear power plants. In the event of a Nankai Trough earthquake, there are fears that a chain of serious nuclear disasters could occur, starting with loss of control of the operating Ikata reactor, followed by the meltdown of spent nuclear fuel in cooling pools, and the loss of control of the Shimane Nuclear Power Plant, four nuclear power plants in Wakasa Bay (Takahama, Oi, Mihama, Tsuruga) and 400 kg of plutonium at Monju.

3. Summary of the proposal
July will be designated as “Disaster Preparedness Practice Month,” and the following measures will be recommended and implemented nationwide.

Proposal 1

Conducting earthquake and tsunami evacuation drills at the citizen level

• Target audience:
  – Citizens living in areas expected to be inundated by tsunamis
  – Citizens living in dilapidated buildings in the epicenter of a Nankai Trough earthquake
• Main actions:
  – Encourage people to live in safe buildings and areas during July
  – Similarly, encourage schools, businesses, and hospitals to operate in safe buildings and areas during July

Proposal 2
Emergency risk reduction measures for nuclear power plants

• Measures for Ikata and Hamaoka nuclear power plants:
  – Shutdown of the Ikata nuclear power plant reactor, and transfer of the nuclear fuel in the reactor to a safe location using transportation casks
  – Emptying and dispersing the spent fuel pools at Ikata and Hamaoka

• Measures for 11 operating nuclear reactors in Kyushu and Western Japan:
  – Temporary suspension of 11 reactors

4. Expected effects

1. Preemptive measures for those who have difficulty evacuating in the event of a tsunami
2. Possible to reduce human casualties caused by building collapses
3. Prevent accidents in nuclear reactors and cooling pools, fundamentally reducing the risk of radiation disasters
4. Permanent strengthening of disaster prevention systems

5. Issues and countermeasures for implementation

1. Securing a destination for nuclear fuel:
   Temporary storage will be done using vacant space in cooling pools at other nuclear power plants and the Mutsu Interim Storage Facility. (July Rehearsal [3])
2. Power shortages due to nuclear power plant shutdowns:
   Adjustments will be made through requests to conserve electricity and the use of renewable energy
3. Living burdens due to evacuation of citizens:
   Utilization of evacuation assistance systems and public facilities
4. Social skepticism towards “predictions”:
   Raising awareness as “training” linked to seismology

6. Conclusion

Even if an earthquake does not actually occur in July, the dry run will prepare people to protect their lives from tsunamis, strong shaking, and nuclear disasters.
Now is the time for realistic action to be taken nationwide to prepare for the “worst case scenario.”

 

Reference:

[1] NHK, Damage estimation of Nankai Trough Earthquake, https://www3.nhk.or.jp/news/html/20250331/k10014762791000.html#anchor-20
[2] Cabinet office, Seismic source zone of Nankai Trough Earthquake, https://www.bousai.go.jp/jishin/nankai/taisaku/pdf/1_1.pdf
[3] July Rehearsal, Dry Run in July for Nankai Trough Earthquake, https://july-reh.org/