Native American tribal leaders are protesting a proposed giant solar power project in southern California they say will do irreparable harm to nearby historical artifacts. The tribal leaders asked the California Energy Commission to make substantial revisions to the project to safeguard their heritage.

The Quechan Indian Tribe’s Historical Preservation Office filed comments with the California Energy Commission (CEC), blasting the design of the project and what it says is a rush by CEC and the federal Bureau of Land Management (BLM) to approve the solar project.

Palen Solar Holdings, a joint venture by BrightSource Energy and Spanish company Abengoa S.A, proposed the solar project, known as the Palen Solar Electric Generating System.

Designed to generate up to 500 megawatts of power, the project would be located on 5,200 acres of BLM land about 60 miles east of Indio, California. The project would feature two 750-foot-tall power towers surrounded by 85,000 reflecting mirrored heliostats.

CEC originally approved a giant solar facility on the site in 2010, but ownership of the development has changed since then. More importantly, the project’s new owners radically redesigned the plans for the project. The new owners have asked the CEC to amend its original certification to account for the new design, and to do so by the end of the year.