Environmental groups filed suit May 23, seeking a federal court order to make the U.S. Environmental Protection Agency update a long-expired cooling water discharge permit for the coal-fired Four Corners plant that was last issued in 2001.
Pinnacle West Capital Corp. subsidiary Arizona Public Service Co., or APS, owns 70% of the 1,540-MW plant on Navajo Nation land in San Juan County, N.M. PNM Resources Inc., the Salt River Project and Fortis Inc. subsidiary Tucson Electric Power Co. own remaining shares.
The permit expired in early 2006 but was administratively extended, and APS, as the plant operator, submitted a revised application in early 2013 with plans to close three of the plant's five units, according to the EPA. APS shut units 1, 2 and 3 at the end of 2013 to comply with the EPA's air pollution rules.
The cooling water for the two remaining operational units, units 4 and 5, comes from the man-made 1,200-acre Morgan Lake next to the plant, which draws water from the San Juan River.
After the water cools the plant's steam turbines, it is discharged back into Morgan Lake, but an outfall pipe discharges from the lake to the No Name Wash, a tributary of the Chaco River, which drains to the San Juan River. The discharges are intermittent and average 4.2 million gallons per day for 2.5 days per week for about six months a year, according to the EPA's account of APS' permit application.
Diné Citizens Against Ruining Our Environment, Amigos Bravos, San Juan Citizens Alliance, Center for Biological Diversity and the Sierra Club filed suit in the U.S. Court of Appeals for the 9th Circuit for an order requiring the EPA to finalize the plant's water pollution permit.
The environmentalists contend the delay is causing significant water pollution, including mercury contamination, because a new permit would require updated pollution control and monitoring equipment.
APS spokeswoman Suzanne Trevino said, "We have maintained compliance with all of the environmental regulations concerning water quality, including the permit that has been administratively continued throughout the years, and have passed numerous on-site inspections from EPA during the time period."
