Overview
- The patrol vessel Zao leaked up to 14.8 kiloliters of heavy oil while moored at Shiogama Port on March 25, producing a surface slick that spread to roughly a 2.7-kilometer diameter.
- Investigators reported that a crew member failed to press an automatic-stop button when operating a pump, a tank alarm failed to sound because of a malfunction, and a night-duty watch officer overslept and did not perform onboard patrols.
- The 2nd Regional Coast Guard publicly released the causation findings on June 19 and has launched an investigation into the Miyagi Coast Guard for suspected breach of the Marine Pollution Prevention Law.
- Local aquaculture was directly hit: wakame, kombu and nori were contaminated, the fisheries cooperative discarded this season’s shipments, and reported losses to marine products have risen above ¥500 million.
- The case highlights gaps in government-vessel safety practices and alarm reliability and could lead to administrative or legal penalties and further remediation measures as the probe continues.