The Earth Centre in Conisbrough, near Doncaster, was built on a former pit at a cost of 55m and was meant to be a major national visitor attraction, focusing on environmental issues.
However, it closed down in the autumn of 2004 owing to disappointing visitor numbers.
Now, plans have been announced by a consortium which plans to turn 50 acres of the 400-acre site into a 12m "Life Park". Derelict land would be restored as nature habitats, while a "solar park" would also be set up as a research area to investigate the potential of solar farms as food sources.
A spokesman for the Rapid Technology Transfer Group, one of the bidders with an interest in the site, said it was still waiting for a response to its proposal from Doncaster Council but was "confident" that its plans would be agreed later this month.
The spokesman said: "Investor interest in the Life Park has been aroused by the quality of the consortium's partners, like Arup, and by the plan to combine business, education, ecology and community interests in a single commercial operation – including three industry and university teaching and demonstration facilities.
"The first restoration activities will focus on areas of productive land that have become overgrown. The consortium's ecology and community partners hope to plant enough cleared land by April to begin the site's food and nutrition programme, with the Life Park aiming to become a specialised training centre in the World Health Organisation's 'Regions for Health' network for Europe.
"The conversion work will create workspaces for businesses with strong environmental credentials and will provide conference and exhibition space plus theatres, classrooms and research areas."
A spokesman for Doncaster Council said the authority had had a "healthy level of interest" in the site and added: "We're looking at a number of bids but no final decision has been made as yet."
Last year, Doncaster Council revealed it cost 200,000 to maintain the site and said it would be inviting tenders for the land, after being unable to find a viable alternative use. Mayor Peter Davies also described the Earth Centre as "one of the largest disasters in the country".