Japanese engineers conceded on Friday that burying a crippled nuclear plant in sand and concrete may be a last resort to prevent a catastrophic radiation release, the method used to seal huge leakages from Chernobyl in 1986.
But they still hoped to solve the crisis by fixing a power cable to two reactors by Saturday to restart water pumps needed to cool overheating nuclear fuel rods.
It was the first time the facility operator had acknowledged burying the sprawling 40-year-old complex was possible, a sign that piecemeal actions such as dumping water from military helicopters or scrambling to restart cooling pumps may not work.
"It is not impossible to encase the reactors in concrete. But our priority right now is to try and cool them down first," an official from the plant operator, Tokyo Electric Power Co, told a news conference.
As of now, the world's worst nuclear crisis since Chernobyl and Japan's worst humanitarian crisis since World War 2 looked far from over.