Abe's Military Base Plan for Okinawa Sinking in Mayonnaise

The Asia Pacific Journal:Japan Focus
February 15, 2019

Abe's Military Base Plan for Okinawa Sinking in Mayonnaise: Implications for the U.S. Court and IUCN

Yoshikawa Hideki

Abe Government's Reluctant Admission

After a long silence, the Abe government has finally admitted that the construction of a U.S. military base at Henoko-Oura Bay in Okinawa requires significant changes to the original land reclamation plan (see Asahi Shimbun). Parts of the seafloor of the construction site have proven to be extremely fragile, having the consistency of mayonnaise. To solidify the seafloor sufficiently to support a functional airport, a "sand compaction pile method" needs to be carried out (see this video for sand compaction pile method). Casing piles will be driven into the seafloor as deep as 60 meters (or 90 meters below the water surface), and the piles, which are hollow, will be filled from the top with sand and other compacting materials. Then the piles are raised or removed slowly leaving the compacting materials in the form of a pillar, thus solidifying the seafloor. This procedure is to be repeated 76,000 times, implanting 76,000 compacting pillars in the seafloor (see Ryukyu Shimpo).


© Asahi Shimbun

Reclamation experts have said that while the sand compaction pile method has been successfully carried out in other regions within Japan, it has never been done to a depth of 90 meters, and there are no pile drivers in Japan capable of reaching to that depth. On this problem the government has so far offered no comment.


Sand Compacting Pile Method © FUDO TETRA.

read more・・・