Correction: Power Plant-Lawsuit story

The coalition of environmental groups, including the San Juan Citizens Alliance and Dine Citizens Against Ruining Our Environment, argues in a 58-page complaint that the defendants failed to thoroughly assess the potential impact the plant and surface coal mine could have on the environment and public health before approving the 25-year extension last July.

The lawsuit names the Interior Department, the Bureau of Indian Affairs, the Bureau of Land Management, Interior Secretary Sally Jewell, the Fish and Wildlife Service and the Office of Surface Mining, Reclamation and Enforcement as defendants.

"The Department of the Interior followed a comprehensive, thorough and transparent evaluation of the environmental impacts of the plant, the mine and the transmission line rights-of-way in coming to its conclusion," said Steven Gotfried, a spokesman for the utility company.

The Navajo Transitional Energy Company would consider as an option its own legal action against environmental groups, arguing that the energy project is protected by tribal sovereignty and treaty rights, according to company spokesman Erny Zah.