The company behind Huntington Beach’s proposed ocean desalination plant has failed to provide key information to state coastal regulators such as cost estimates and seismic risks needed for the project’s approval, according to a letter issued last week by the California Coastal Commission.

Ten months after the commission’s most recent request, Poseidon Resources “provided some of the necessary information, but was only partially responsive to other requests or provided information other than what we requested,” wrote Tom Luster, an environmental scientist at the Coastal Commission, in a March 20 letter to the company.

The letter details 18 specific items of information regulators say they requested last May but that Poseidon has either not provided, declined to provide or given an inadequate response.

The requests include an on-site verification of whether wetlands exist at the site, the expected acidity of the plant’s discharge into the ocean, the latest expected project costs and required studies of seismic hazards. An earthquake fault runs directly under the project site, the letter states.

According to the letter, Poseidon also declined to provide the expected velocity of seawater into its intake. Luster wrote that the data is needed to calculate effects on marine life.

Poseidon, however, says it has both fully addressed the commission’s concerns and “plans to complete” the intake velocity calculations.

“We feel we have more than adequately responded to all those questions,” said project spokesman Brian Lochrie. Back-and-forth communication between the company and coastal regulators has gone on for years, he said. “It’s par for the course for the Coastal Commission.”

As planned, the Huntington Beach plant and a similar proposed Poseidon facility in Carlsbad would be the largest desalination plants in the Western Hemisphere.

Supporters say the Huntington Beach plant would create jobs, produce a local, reliable water supply for southern Orange County and ultimately cost less than imported water.

But the project has met stiff opposition from environmentalists, who say large-scale desalination is highly energy-intensive, damages marine ecosystems and costs significantly more than current water prices.

The Coastal Commission staff is reviewing Poseidon’s application for a conditional use permit for its Huntington Beach facility, which is required before construction can start.

Another concern raised by the commission is the project’s increasing cost estimates.

As part of the Coastal Commission’s review, it conducts an “independent assessment” of alternative intakes and other components to ensure the plant has the least impact on the environment while still being a financially feasible project.

In order to do that analysis, Luster wrote, the commission needs updated figures on the plant’s expected cost, which Poseidon declined to provide.

The expected cost for Poseidon’s Carlsbad project recently increased from $270 million at the time of its Coastal Commission hearing to more than $800 million, according to Luster. The increase was “well above the $150 million Poseidon estimated for at least one of the alternative intakes that it said would make the project economically infeasible,” Luster wrote.

In an email, Poseidon Vice President Scott Maloni said the Huntington Beach project’s increased budget hasn’t changed the overall project’s feasibility. The company will provide updated budget figures in their next response to the commission, he said.

A local environmental group says it plans to hold Poseidon’s “feet to the fire” over its permit application.

“If a contractor promises to bring in a project at a set cost, as Poseidon did in Carlsbad, and suddenly that cost increases by 300 percent, it’s time to start asking some hard and fast questions, and we intend to get the answers,” asserted Garry Brown, executive director of Orange County Coastkeeper, in a prepared statement.

Poseidon, meanwhile, is confident that coastal regulators will approve its permit even if it requires some brinkmanship.

Lochrie said that with the Carlsbad project, Poseidon ended up telling the commission’s staff that the company would go straight to the commission itself for approval. “Once we said that, then suddenly the staff agreed that the application is complete,” he said.

You can reach Nick Gerda at ngerda@gmail.com, and follow him on Twitter: twitter.com/nicholasgerda.

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