TORONTO - Ontario's privacy commissioner is again ordering the release of key data related to a planned landfill site north of Barrie, Ont.

Ann Cavoukian says she will take "all possible steps," including legal action, unless Simcoe County turns over hydrogeological data.

She says the order follows one issued in mid-May to Simcoe County telling it to obtain records from an engineering consulting firm.

But Cavoukian says in failing to obtain the records from the consultants, the county has failed to comply with the initial order.

The proposed landfill, known as Site 41, is facing strong opposition from area residents who fear the site will poison a pristine aquifer.

On Thursday, noted U.S. environmental activist Ralph Nader appealed for a halt to construction on the landfill project. In a letter to Dalton McGuinty, Nader asked the premier not to rush to dump "putrid waste" atop the Alliston aquifer.