Five sites in Scotland which were considered for dumping nuclear waste, have been publicly unveiled for the first time.
The list was disclosed by Nirex
The list was obtained under the Freedom of Information Act after being kept under wraps for 20 years.
Scotland's sites were identified as Dounreay and Altnabreac in Caithness, an under-sea site off Hunterston and two small Hebridean islands off Barra.
The sites were revealed on Friday by the nuclear disposal company Nirex.
Campaigners said publication of the list of locations, which were never used, only came after a long fight and a request under the Freedom of Information Act.
They appeared on the Nirex website under the title "Nirex publishes historic site list".
It names the uninhabited island sites as Fuday and Sandray in the Western Isles which critics describe as the "most interesting" on the map.
An application was eventually put in to use a site at Sellafield, but was rejected by the government.
A new site selection process will start, however, in a couple of years.
The independent Committee on Radioactive Waste (CoRWM) is currently considering the disposal of long-standing radioactive waste in the UK.
A spokeswoman said: "The list was an early part of a previous process which came to a halt in 1997 and has nothing to do with our process. We had not seen the list and it will not be used in our work.
"We have no pre-conceptions about the right way to manage wastes and deep disposal is only one of the options we are assessing."
She continued: "We appreciate that people in the named areas may feel concerned.
"We are committed to involving the public in our deliberations and invite people to direct their energy into the current policy process. Transparency is the watch word."
But environmental campaigners fear nuclear disposal experts may yet return to the previously hidden list as they seek a long-term solution to the radioactive waste issue.
Opponents stressed that Nirex had made it clear that since the geology of Britain had not changed, all the original sites could be considered again to host a radioactive dump.
Nirex managing director Chris Murray said: "Radioactive waste exists and needs to be dealt with whether or not there is any programme of new-build in the UK.
"Many things have changed since this old list was drawn up, but what has not changed is that the waste still exists and needs to be dealt with in a safe, environmentally sound and publicly acceptable way for the long term. Responsibility lies with this generation to ensure this is done".
He added: "Dealing with the waste is as much an ethical and social issue as a scientific and technical one. This is the key lesson we have learned from the past. Openness and transparency must underpin everything that is done in this area."
However, critic Rob Edwards, who writes for The Sunday Herald and New Scientist, said: "It's just a sign of the inherent characteristic secrecy of the whole nuclear operation in the past.
"I and others have been asking for this for more than 15 years. Nirex wanted to keep it out of the general election but they have now agreed and government ministers have agreed.
"The government feared that releasing this information could cause planning blight and panic in the areas.
"I don't think it was logical or sensible to keep it secret because by releasing it now they're going to create more trouble for themselves than had they released it 15 years ago."
He added: "None of us got the list completely right. I don't think we'd got these two islands around Barra and there were a couple of sites in England that we hadn't guessed either. It came as a surprise.
"Assuming we decide to bury our waste deep underground, which is what most countries and most experts think is right, we will have to go through this exercise again.
"Nirex itself says that if we do that we are likely to end up with a similar, but not identical, list.
"Any of the sites that have been previously selected could well be selected again. It's common sense."
Mr Edwards, who said the confidential list was regarded as "incredibly sensitive" by the authorities, went on: "We know more about the risk of climate change, which could rule out coastal sites for example.
"But if you are on the old list, you stand a very good chance of being on any new list.
"All we do with our waste at the moment is leave it where we produce it, at the nuclear power station sites. There are very high concentrations of waste at Dounreay and Sellafield in Cumbria."
Duncan McLaren, of Friends of the Earth Scotland, said: "It is an absolute disgrace that the location of these sites has been kept from the public for so long.
"However, the way in which the details of this list have now finally been forced into the public domain has been a complete shambles, too. It certainly does not inspire any confidence in the nuclear industry or the government on this subject."
He added: "Despite what ministers might say, Nirex has made it quite clear that each of the sites considered geologically suitable in the past could just as easily be considered suitable in the future.
"We therefore urge every community named on this list to begin taking steps to help halt plans to expand nuclear power in the UK."
Scottish National Party environment spokesman Richard Lochhead said: "Radioactive waste must be stored safely. However, it is not acceptable that five of the 12 short-listed sites selected as possible nuclear dumps are in Scotland.
"This can only suggest that Scotland was being lined up as the UK's nuclear waste dump and no doubt, it will continue to be the case that the people of Scotland will have to pay the price for Labour's nuclear obsession."
Scottish Green MSP Chris Ballance said: "This list should have been made public long ago.
"Contrary to claims from Nirex and government ministers, this is not a shining example of open government but more an example of government bodies finally giving in after their arms have been twisted."