"We're in favor of making sure our plant has state-of-the-art equipment," said Damon Gross, a spokesman for Arizona Public Service, which operates the 1,027-megawatt Cholla Power Plant near St. Johns. "The question becomes, what is the benefit you're getting versus the cost of what customers are going to assume because of that."
EPA's proposal would mean a $436 million investment among Cholla's owners, which Gross said would be passed on to ratepayers. The bill for residential users would go up nearly $19 a year, while small business customers would pay almost $32 more annually, he said.
The Salt River Project, which owns and operates the Coronado Generating Station near Holbrook, said it would be on the hook for another $119 million under the EPA's proposal. Kelly Barr, the senior director of environmental management policy and compliance for SRP, said that's on top of a $500 million investment that partly came out of a previous consent decree with the EPA for upgrades.
"We felt like we had met a very high standard of compliance," she said. "We felt like we would be done at that facility for a while."
A spokesman for Arizona Electric Power Cooperative wrote to the EPA earlier this year to say the company estimated it could be forced to spend up to $219 million. The cooperative runs the Apache Generating Station near Cochise.