By Jim T. Ryan Staff WriterDuncannon and The Nature Conservancy are expected to close in September on their deal to preserve the borough's watershed properties along Shermans Creek and the north wing of Cove Mountain, according to an update from the conservancy.Josh Parrish, the conservancy's working woodlands director who helped broker the deal last year, told borough council in July that all fundraising is complete and the expected closing date is Sept. 15. As part of the deal, the conservancy will give the borough $550,000 at closing to buy the development rights on the nearly 1,600...…By Jim T. Ryan Staff WriterDuncannon and The Nature Conservancy are expected to close in September on their deal to preserve the borough's watershed properties along Shermans Creek and the north wing of Cove Mountain, according to an update from the conservancy.Josh Parrish, the conservancy's working woodlands director who helped broker the deal last year, told borough council in July that all fundraising is complete and the expected closing date is Sept. 15. As part of the deal, the conservancy will give the borough $550,000 at closing to buy the development rights on the nearly 1,600...WW…