TEPCO plans to spray resin on the ground around the plant to keep radioactive particles from spreading or seeping into the ocean. The company will test the method Thursday in one section of the plant before using it elsewhere, Nishiyama said.
"The idea is to glue them to the ground," he said. But it would be too sticky to use inside buildings or on sensitive equipment.
The government also is considering covering some reactors with cloth tenting, TEPCO said. If successful, that could allow workers to spend longer periods of time in other areas of the plant.
The spread of radiation has raised concerns about the safety of Japan's seafood, even though experts say the low levels suggest radiation won't accumulate in fish at unsafe levels. Trace amounts of radioactive cesium-137 have been found in anchovies as far afield as Chiba, near Tokyo, but at less than 1 percent of acceptable levels.
Experts say the Pacific is so vast that any radiation will be quickly diluted before it becomes problematic. Citing dilution, the U.S. Food and Drug Administration has played down the risks of seafood contamination.
As officials seek to bring an end to the nuclear crisis, hundreds of thousands in the northeast are trying to put their lives back together. The official death toll stood at 11,257 on Wednesday, with the final toll likely surpassing 18,000.
The government said damage is expected to cost $310 billion, making it the most costly natural disaster on record.
In the town of Rizukentakata, one 24-year-old said she's been searching every day for a missing friend but will have to return to her job at a nursing home because she has run out of cash.
Life is far from back to normal, she said.
"Our family posted a sign in our house: Stay positive," Eri Ishikawa said. But she said it's a struggle.
Associated Press writers Eric Talmadge in Fukushima, Jay Alabaster in Rikuzentakata, and Shino Yuasa, Noriko Kitano and Elaine Kurtenbach in Tokyo contributed to this report.