Power Plant Must Prove Cooling System Safe

May 15 - Oakland Tribune

The operator of a controversial power plant that draws 226 million gallons of water a day from the San Francisco Bay to cool its turbines has 21/2years to either prove its pumps cause no harm to the Bay or shut them down.

The compromise decision, handed down last week by the San Francisco Regional Water Quality Control Board, pleased activists and the power plant's operator, Mirant California LLC.

Activists are certain Mirant will never prove that such a massive draw from the Bay -- 26,000 gallons in the time it takes to read this sentence -- causes no harm to the Bay's environment or wildlife. Mirant, however, was happy to get its permit and confident that studies under way would show that the impact is minimal.

"The board was balanced," said Jeff Russell, Mirant's vice president of business operations. "They came to a good decision and were very reasoned in their approach."At issue is a 40-year-old cooling system at the Potrero Power Plant in one of San Francisco's poorest neighborhoods. City officials and community and environmental activists have long wanted to shut the plant, saying it is a blight on the neighborhood and an inefficient and polluting power source.

On Wednesday, a coterie of opponents, including two San Francisco city supervisors, the city attorney and the director of the city's Public Utilities Commission, asked the board to deny or sharply restrict the plant's permit, which expired in 1999.

The evidence, they said, was irrefutable:

- Mirant's own consultant concluded upward of 300 million fish eggs and larvae are destroyed every year as they are sucked into cooling system's twin pumps.

- Water gushing out of the plant is 10 degrees warmer and scours the bottom of the Bay, kicking up a plume of sediment.

- The sediment contains PCBs, mercury, lead, arsenic, chromium and other industrial pollutants that would otherwise remain undisturbed on the Bay floor.

- State and federal regulations prohibit the construction of any new plants with so-called "once-through" cooling systems, based on the environmental cost such systems exact.

Water board staff members disputed many of those points, saying the evidence was uncertain. But the board overruled them.

"Pulling 226 million gallons a day out of the Bay just doesn't sound right," said water board member Clifford Waldeck. "No new 'once-through' cooling plants are being built. This is a once- through plant. Why would we as a board want to go forward with a process that's not being used anymore?"

Voting 7-1, the board shaved 21/2 years from Mirant's proposed permit and vowed not to renew the permit unless Mirant could show it caused no harm. The new permit expires at the end of 2008.

Mirant was unconcerned by the change or the saber rattling. Under federal rules the company must make a similar case about its cooling system to the U.S. Environmental Protection Agency next year.

"We would have to present that stuff and lay out the plan for how we're going to get there anyway," Russell said.

The 362-megawatt plant is considered necessary to meet San Francisco's power needs under state rules; Mirant, in other words, must run it. If the water board in 2008 requires Mirant to upgrade its cooling system, that cost would be passed on to ratepayers.

But the city is building new gas-fired power plants that would likely render Mirant's Potrero facility surplus in the state's eyes. If that happens, Mirant would foot the bill for any upgrades required by the water board.

And that has activists confident the board's ruling sounded the plant's death knell.

"Three hundred million larval fish killed per year, not to mention other impacts -- that's a pretty high hurdle to get over. And the burden's on Mirant," said Greg Karras, senior scientist for Oakland-based Communities for a Better Environment.

"The board did what we wanted. ... (The discharge) harms the Bay. Let's recognize that and deal with that by the real solution of getting it out of the Bay."