Welcome to Japan, land of cherry blossoms, sushi and sake, and 17,000 metric tons of highly radioactive waste.

That's what the country has in temporary storage from nuclear plants. Supporters of nuclear power say it's cleaner than fossil fuels for generating electricity. Detractors say there's nothing clean about what's left behind, some of which remains a deadly environmental toxin for thousands of years.

Since nuclear power was first harnessed more than 70 years ago, the industry has been trying to solve the problem of safe disposal of the waste. Japan has been thrown into the center of the conundrum by the decision in recent months to retire five reactors after the Fukushima disaster started in 2011, while the restart process for one reactor was recently approved despite public opposition.