The owner of a former cement works earmarked for a renewable energy village has confirmed it is in exclusive talks with a private buyer.
Lafarge Tarmac was planning to sell the £1.4m site at Eastgate in Weardale at auction on Thursday.
But the company has now confirmed it withdrew the property from public auction after entering private talks.
Meanwhile, Durham University hopes new owners will continue to explore the site's geothermal potential.
A spokeswoman for Lafarge Tarmac said: "We can confirm we are no longer putting the Weardale site up for public auction.
"We are in exclusive talks with a private buyer. We cannot comment further at this stage."
The former cement works closed in 2002 with the loss of nearly 200 jobs.
The 431-hectare (1,065-acre) site contains two of the most recent deep geothermal boreholes to be drilled in the country.
Dr Charlotte Adams, research manager for BritGeothermal at the Department of Earth Sciences at Durham University, said: "The boreholes at Eastgate are an important resource for understanding the UK's geothermal potential.
"Geothermal energy can help the UK become more self-sufficient and resilient with respect to energy in the future.
"We therefore hope that any subsequent site owner will view the boreholes as an asset and continue to support their use for Research and Development purposes."
The site's quarry is currently being used by ITV for filming of a series based on Beowulf.