A conservation group has agreed to buy 171 acres of Lake Michigan shoreline sand dunes in Saugatuck from Aubrey McClendon, co-owner of the NBA's Oklahoma City Thunder.

The Land Conservancy of West Michigan has been working with The Nature Conservancy and the city of Saugatuck to acquire the property. The cost would be about $23.2 million.

The deal hinges on getting a $12.6 million state grant in early December. Contributions would cover the rest.

About $6.1 million has been donated. If the grant goes through, the Land Conservancy would temporarily take ownership of the property in late December and a campaign would begin to raise the remaining $4.5 million.

The goal is to complete fundraising within three years, at which time the city would take permanent ownership.