According to Japanese authorities, the leak of highly contaminated water from the cable storage pit located next to the Unit 2 inlet point at Fukushima Daiichi nuclear power plant has stopped as of 20:38 UTC on 5 April.
Workers had employed measures to stop the flow of water directly to the sea since 2 April, when the leak was first observed.
On April 2, concrete was poured into the pit in an attempt to stop the water leakage to the ocean, but no significant decrease in leakage was observed.
From 4:47 to 5:30 UTC on April 3, the top of the trench was broken open and polymer was poured into the trench to stop the leakage of water, but this measure was not successful.
Approximately 13 kg of liquid tracer was injected into the pit at 22:08 UTC 3 April. The tracer was also injected into two new bore holes that had been drilled near the pit.
At 4:15 5 April UTC it was confirmed that the tracer was seen leaking from the crack into the sea.
At 6:07 UTC 5 April coagulation agents (liquid glass) were injected into the holes drilled around the pits.
The leakage was reported to have ceased at 20:38 UTC on April 5.
Work continues to prevent further releases to the sea.