North Carolina water quality officials have dealt a major blow to Alcoa in its effort to obtain a new hydropower license on the Yadkin River. The Division of Water Quality is revoking its endorsement of the project because it says Alcoa intentionally withheld key information. Until last Friday, the state Division of Water Quality was in Alcoa's corner, testifying on the company's behalf in a lawsuit over what's called a "401 water quality certificate." The state issued the certificate in 2009, but some of Alcoa's opponents appealed it. Then in court on Friday, state water quality officials discovered they'd been double-crossed. Division of Water Quality spokeswoman Susan Massengale says Alcoa "intentionally withheld some information" from the state. "What the emails that were entered into the hearing indicate is that Alcoa felt their technology was not going to meet water quality standards 100 percent of the time, and that is required." says Massengale. Now the Division of Water Quality is revoking the 401 certificate it had previously issued. That's a big problem for Alcoa. The company must have the certificate in order to keep operating four dams on the Yadkin River and selling the electricity for a profit. Alcoa spokesman Mike Belwood says the company will appeal the decision to revoke its certificate. "It's important to put this in perspective," adds Belwood. "Developing a compliance plan is complex and involves a lot of discussion and debate. The messages that are in question are just a few conversations among thousands that occurred over a long period of time and they weren't material to the final result." Regardless of those emails, Belwood says Alcoa's dams will meet state water quality standards. But state officials now wonder if they were too trusting of Alcoa in the certification process. The emails would not have come to light had the original water quality certificate not been challenged by the Yadkin Riverkeeper and Stanly County. They want the state to take over the hydropower project. Alcoa originally built the dams nearly a century ago to power an aluminum smelter, which it has since closed.