Nuclear power. Japan's nuclear renaissance dogged by waste challenge.

Later this spring, Japan is likely to restart the first two of the 48 nuclear reactors idled in the aftermath of the 2011 meltdowns at the Fukushima Daiichi Nuclear Power Station. But the resumption of nuclear power generation is refocusing attention on a lingering challenge: what to do with the spent fuel. When Japan turned to nuclear power in the 1960s, it worried about uranium supplies and wanted to minimize the amount of nuclear waste. So it planned on spent fuel reprocessing, which reduces the volume of waste needing long-term storage and produces fresh fuel for reactors. A private firm owned by the country9s nuclear utilities started building a reprocessing plant in the northern village of Rokkasho in 1993. But it took more than 2 decades to work the kinks out of an experimental vitrification process. The plant is finally due to come online in spring 2016. But the country is still searching for a site for a deep underground repository for the highly radioactive nuclear waste left over from reprocessing. For the time being, it will be encased in glass and stored until a permanent solution is found.