In a move that will further delay the already controversial Cape Wind project, the National Park Service announced Monday that Nantucket Sound was eligible for listing on the National Register of Historic Places. This decision came as a reaction to a request from the Mashpee Wampanoag of Cape Cod and the Aquinnah Wampanoag of Martha’s Vineyard, who claim the 130 proposed wind turbines would thwart their spiritual ritual of greeting the sunrise and disturb ancestral burial grounds.

In the works since 2001, this extensive wind project is the nation’s first planned offshore wind farm. It would cover 24 square miles in the sound, an area roughly the size of Manhattan. This latest development creates new hurdles by requiring more negotiations, further delaying the project. Locals hope that these new restrictions will convince the project’s developer, Energy Management Inc., to move the site. Interior Secretary Ken Salazar set a deadline of March 1 for the tribes and the project’s developer to figure out a solution.

Cedric Cromwell is the chairman of the Mashpee Wampanoag tribe. He told the New York Times  that the decision confirms “what the Wampanoag people have known for thousands of years: that Nantucket Sound has significant archaeological, historic and cultural values and is sacred to our people.” Further, the tribes feel that the proposed wind turbines could destroy long-submerged tribal artifacts from thousands of years ago, when the sound was dry land.

The state says it is puzzled by the ruling. “The decision is without precedent in terms of implicating many square miles of what is, legally speaking, the high seas,” said Ian A. Bowles, the Massachusetts secretary of energy and environmental affairs. Nantucket Sound encompasses more than 500 square miles and is by far the largest body of water ever found eligible for listing on the national historic register. Bowles adds that things are not quite over for the energy project. “… As a procedural matter, it’s a good thing a decision was reached, and the secretary is getting personally involved to get it over the finish line.”

Cromwell’s tribe, which won federal recognition in 2007, is also currently seeking build a casino in the coming years.