Japan earthquake: Radioactive leak plugged at reactor

Tepco said it had injected chemical agents to solidify soil near a cracked pit that was the source of the leak.

Engineers have been struggling to stop leaks since the plant was damaged by the earthquake and tsunami on 11 March.

They are currently discharging less contaminated water into the sea so more radioactive water can be stored.

Since the earthquake knocked out cooling systems workers have been pumping water into reactors to cool fuel rods, but must now deal with waste water pooling in and below damaged reactor buildings.

Engineers also face a potential new problem of a build-up of hydrogen gas in one of the reactors at the six-unit plant. Tepco said it could inject nitrogen gas into the No 1 reactor to prevent an explosion.

Blasts caused by a build-up of hydrogen gas took place in three reactors in the aftermath of the earthquake.

'Water glass'

Plugging the leak from the pit in the No 2 reactor represents a measure of success for engineers at the plant, analysts say.

It is thought to have been the source of high levels of radiation found in seawater close to the plant.

In order to stem the leak, Tepco (the Tokyo Electric Power Co) injected ''water glass'', or sodium silicate, and another agent into the pit.

Desperate engineers had also used sawdust, newspapers and concrete in recent days to try to stop the escaping water; Kazinform cites BBC News.

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