A radioactive waste dump has been banned in South Australia - but only for four months.

After a day-long special sitting, the State Government's Bill, banning a dump and the transportation of waste in SA, was pushed through the Upper House last night, with help from independents and the Australian Democrats.

But Environment Minister John Hill had to compromise to secure the passage, agreeing to a sunset clause that the legislation expire on July 19.

He agreed to produce a strengthened Bill after that period, which would have to go back to Parliament.

The compromise came after No Pokies MLC Nick Xenophon and rebel Liberal Julian Stefani sought advice on the Bill from legal experts Andrew Tokley and Simon Ower.

"The gist of the advice from the two constitutional lawyers was that the legislation should be improved," Mr Xenophon said.

Last night Mr Hill hailed the vote, saying: "This is an excellent outcome for South Australia.

"All but a handful of Liberal members voted for the Government's position so this is a great outcome," he said.

"Then state now has legislation to say 'no' to a radioactive waste dump."

But Opposition environment spokesman Iain Evans said the outcome showed the Bill was ineffective.

"We know that that the Government's own Bill is flawed to such an extent that we have to come back and re-debate it in four month's time," he said. "The Government's got 200 Crown solicitors that worked on this for a year. One private lawyer in less than 24 hours has sent the Minister's policy into a spin to such an extent that we're back in four months re-debating the issue." Mr Evans said there was "absolutely no doubt" that the Government had committed to launching a High Court challenge - at a cost of more than $2 million ? if a dump were forced on SA.

A series of meetings yesterday afternoon between the independents and the Government sealed the deal.

Mr Xenophon, Mr Stefani, Australian Democrats leader Sandra Kanck, Family First MLC Andrew Evans and independent Terry Cameron were briefed by the constitutional lawyers on the ramifications of the Bill and also met Solicitor-General Chris Kourakis.

Then after 4pm yesterday, Mr Xenophon moved the amendment to the Bill in the Upper House, surprising and angering Opposition MLCs who were set to vote against the legislation.

"At the end of the day, South Australians will have a stronger piece of legislation that will have a much greater chance of withstanding any Commonwealth challenge," Mr Xenophon said after the vote.

Liberal MLC Angus Redford told the Upper House: "I have never been so embarrassed and so ashamed of being a member of this council, having watched the shenanigans that have gone on over the last few hours."

THE workings of the Upper House of the South Australian Parliament may well be beyond most of us at the best of times. On a day like yesterday, it is no contest.

The manoeuvrings and pure farce which accompanied the Legislative Council debate on the proposed national radioactive waste dump in northern SA were, unfortunately, classic.

At least by the end of the day's proceedings, there was a result - a vote banning a dump in this state. Well, there was a result for a short time, for Environment Minister John Hill had to compromise to ensure his Bill's passage.

That compromise is a sunset clause which expires on July 19 and which proponents claim will result in legislation which is strong and more effective still.

That does not change the fact that regardless what the elected representatives of SA vote, they will be arrogantly ignored by the Federal Government. This is a government which decided from day one the dump was coming to SA come hell or high water.

Forget public consultation before any decision; forget actually asking the people of this state what they feel; forget democracy.

The truth is the Federal Government does not need our permission to establish the dump on crown land. The truth is it dimisses our reasonable concerns out of hand.

This is the very heart of the debate, not the petty politicking which has erupted in recent months. Of course the Government's stand will ultimately be fruitless. Of course SA will, through common sense, ultimately use the national repository.

In this matter, Premier Mike Rann and his Government clearly speak for the people. The state with a clean, green image does not want to become a national dumping ground. It is a pity nobody in Canberra can be bothered listening.