The Science Council of Japan has expressed concerns about the country's nuclear waste disposal policies.

The Science Council advocates keeping radioactive debris from the country's nuclear reactors in "temporary safe storage" sites. The problem within Japan is to find a geologically safe storage area, given the country's history of seismic activity.

"Based on current scientific knowledge, we cannot determine a geological formation that would be stable for hundreds of thousands of years," Science Council of Japan member Harutoshi Funabashi, a professor at Hosei University, told The Japan Times.

"And thus the best possible option is temporary storage. This does not mean postponing the problem irresponsibly to the future. It is to secure time to find ways to more appropriately handle the matter."

Safe disposal of nuclear waste is a growing problem worldwide among the countries operating nuclear power plants.

Concerns about nuclear power and waste disposal are highest in Japan, where on March 11, 2011, Tokyo Electric Power Co.'s Fukushima Daiichi NPP was rattled by an offshore magnitude-9.0 earthquake. The tremor generated a tsunami that effectively destroyed the complex.

Dry casks containing nuclear waste at the Fukushima Daiichi were knocked over but no radiation leaked from them. There was, however, release of radiation from spent fuel pools.

Japanese government officials estimate that the radiation spewed from the crippled Fukushima Daiichi reactor complex affected anywhere from 386 to more than 1,500 square miles.

Concerns about the eventual disposal of nuclear waste are also high in the United States, where the first civilian NPPs for generating electricity were built. There are 104 commercial reactors, generating about 20 percent of the nation's electricity.

From the 1980s to 2008, the U.S. government developed a plan to shift nuclear NPP waste to a permanent storage facility at Yucca Mountain in Nevada. But four years ago, the Yucca Mountain Repository development ended when scientists established the proposed facility's high risk for groundwater contamination.

Until another geological repository can be developed, the Nuclear Regulatory Commission's plan is to continue to store spent nuclear fuel at the plants where it is generated.

Tokyo's proposed current solution to its mounting nuclear waste problem is to reprocess spent nuclear fuel into vitrified high-level radioactive waste, which is to be placed in a final disposal site more than 1,000 feet underground after being stored for about three-to-five decades for cooling.

Another advanced nuclear society, Germany, in the wake of the Fukushima Daiichi NPP emergency, decided to abandon nuclear power production entirely. German Chancellor Angela Merkel announced that Germany, the world's fourth-largest economy and Europe's biggest, would shutter all of its 17 nuclear power plants between 2015 and 2022.

Seeking alternative sources of power, Germany's German Development Bank announced its intention to underwrite renewable energy and energy efficiency investments in Germany with $137.3 billion over the next five years.