CHESTERTON, Ind. (AP) — Construction has resumed on a private, yearslong project to redevelop a historic pavilion at Indiana Dunes State Park.

Pavilion Partners LLC member Tom Collins says new windows will be installed soon, and the private group aims to complete all work by May 2020 on the pavilion that’s set among the dunes.

Collins tells The (Northwest Indiana) Times that Pavilion Partners received a construction design release from Indiana in January allowing work to continue.

Environmental groups oppose elements of the privatization deal awarded to developer Chuck Williams, who’s the Indiana Republican Party’s treasurer.

Dunes Action co-founder Jim Sweeney says Indiana’s Department of Natural Resources still hasn’t obtained a historic preservation certificate of approval.

DNR spokeswoman Tara Wolf says it’s received a letter of clearance.