STOCKHOLM – A Swedish nuclear industry group applied to authorities Wednesday for permission to bury nuclear waste for the period it is unsafe, but Greenpeace protesters warned of the risks of leakage.

If the plan is approved, Sweden could become the first country in the world to bury spent nuclear for the whole time it is considered dangerous, which is around 100,000 years.

The Swedish Nuclear Fuel and Waste Management (SKB) applied to build an end-repository in Forsmark, in the centre of the country, and a mid-term storage capsule in Oskarshamn in the south, company spokesman Carl Sommerholt said.

The application handed to the Swedish Radiation Safety Authority would see the waste from the country's 10 nuclear reactors buried 500 metres (1,640 feet) underground.

"After 30 years of research, we feel we have a solution that, if built the way we suggest, will provide a secure end-storage system," Sommerholt told AFP.

Sommerholt said the proposal would be assessed and it would likely take a few years at least before SKB could receive the green light to begin building.

"We hope we will be able to start construction around 2015," he said.

SKB is owned by Sweden's nuclear power plant owners.

Around 25 Greenpeace protestors gathered outside the company's offices in downtown Stockholm Wednesday before it handed in its application, saying there was no guarantee against leakage and asking SKB to reconsider lodging the bid.

"There is still a lot of criticism from many scientists saying the methods they are using cannot guarantee that no radioactivity will leak out during the 100,000 years that this is dangerous waste," Martina Krueger, who is in charge of energy matters at Greenpeace, told AFP.

The protesters were dressed in white nuclear protection jumpsuits and masks resembling a mix of yellow radiation warning signs and Norwegian master Edvard Munch's Scream.

The message the protesters wanted to convey to SKB, Krueger said, was: "Do further investigations to find a way to do this where you can really guarantee that no radioactivity will leak out, and don't pretend that you have the answer."

"The dangers of radioactivity are quite obvious today," she said, referring to the nuclear catastrophe in Japan but adding the protest was not linked to fears over the quake-hit plants there.