"Two and a half years after the worst nuclear disaster since Chernobyl, the operator of Japan's wrecked Fukushima plant faces a daunting array of unknowns."

"Why the plant intermittently emits steam; how groundwater seeps into its basement; whether fixes to the cooling system will hold; how nearby groundwater is contaminated by radioactive matter; how toxic water ends up in the sea and how to contain water that could overwhelm the facility's storage tanks.

What is clear, say critics, is that Tokyo Electric Power Co is keeping a nervous Japanese public in the dark about what it does know.

The inability of the utility, known as Tepco, to get to grips with the situation raises questions over whether it can successfully decommission the Fukushima Daiichi plant, say industry experts and analysts."

Antoni Slodkowski and Mari Saito report for Reuters July 30, 2013. [2]