this really doesn't have anything to do with Y2K computer problems, but it speaks volumes of how stupid my electric provider is. God help us next winter.

http://chicagotribune.com/business/businessnews/article/0,2669,ART-29923,FF.html

Dead zebra mussels may haunt ComEd plant this summer

By Peter Kendall Tribune Environment Writer June 8, 1999

One could not have picked something more unlikely, more ridiculous even, to cause the first stumble in Commonwealth Edison's campaign to provide reliable electric service this summer.

On Monday, one of the first scorching-hot days of the season, ComEd executives swallowed hard and acknowledged that their LaSalle Nuclear Power Station was running at reduced capacity because its cooling systems had been clogged -- with dead zebra mussels.

Throughout the summer, utility officials expect they will have to power down one of the two reactors at the plant periodically so workers can suction out pungent masses of dead zebra mussels that have gummed up one of the plant's cooling systems.

Although officials say they believe they can manage the problem so that it does not affect the supply of electricity to the region this summer, they are painfully aware that it is just the kind of goof-up that has landed the utility in trouble before.

Last summer, the legacy of years of mismanagement kept ComEd from running all its nuclear plants -- contributing to dire shortages of electricity when the season heated up.

Going into this summer, a beefed-up, buffed-up ComEd has pledged: "All 10 units, all summer." And the showpiece of the promised turnaround has been the rehabilitation of the long-troubled LaSalle County plant, about 55 miles southwest of the Loop.

Oliver Kingsley, ComEd's nuclear power boss, said the zebra mussel problem at LaSalle is "not a dagger in the heart." But he acknowledged that the company missed a chance last summer to clear out the tunnels and now will have to live with the problem, which officials hope will wane as summer progresses.

"Would I have liked it if we had gone in there and cleaned out those zebra mussels?" he asked. "You are damned right."

On Saturday, for the second time in just three weeks, one of the two reactors in the LaSalle plant had to be powered down to 60 percent capacity to be cleaned of zebra mussels. In the three weeks between cleanings, dead mussels had clogged 40 percent of the pipes in a cooling system needed to run the plant.

Once the mussels are sucked away, the plant can be throttled back to full power. But because of a completely unrelated problem -- a leak in a uranium fuel rod inside the reactor -- operators have to bring the plant back to full power more slowly than usual.

By Tuesday, ComEd is expecting both reactors at LaSalle to be humming at 100 percent power.

Nevertheless, as summer approaches, ComEd has a plant that will have to be powered down more often than it would like and can't be powered up as quickly as it would like. Officials said they don't know how many times they will have to power down the plant.

Kingsley said that by monitoring the problem, plant operators can schedule the mussel-clearing work for weekends, when demand for electricity is lower.

But he said he could not rule out work being done during the week.

The problem does not affect safety systems at the plant, which are used to cool down the reactors quickly. Those cooling systems have been checked and are clear of mussels, officials said.

At LaSalle, the hot nuclear fuel cooks water into steam, which drives the turbines that turn the generators that make electricity.

The steam is then condensed back into water when it passes over pipes filled with water from a lake alongside the Illinois River. Those are the pipes that are being clogged by the mussels.

As part of their underwater march across the Midwest since the 1980s, zebra mussels made their way into the Illinois River from the Great Lakes via the Chicago River.

Like any power plant situated on a body of water infested with the mussels, the LaSalle nuclear station has an elaborate set of systems to stop the mussels from glomming onto every surface they can reach.

The plant employs two mussel-killing poisons, a carbon-dioxide injection system and a periodic scraping and sucking.

But while ramping up the plant last summer to get it on-line during the power shortages, the LaSalle crew made what officials now acknowledge was a serious error.

They operated the plant for about 30 days without using the mussel-killing poisons that zap the larvae at the intakes. That monthlong lapse apparently allowed the mussels to begin colonizing a 1,500-foot-long, 16-foot-wide intake tunnel leading to the plant, company officials said.

ComEd continued to run the plant, unaware that a burgeoning mussel colony was blossoming along the interior of the tunnel.

Once the mussels were established, turning on the poisons, called "biocides," at the intakes did nothing to kill them.

"They just clam up when the biocides are introduced," said Jeff Benjamin, the top boss at the LaSalle plant.

But what the poisons couldn't do, rising temperatures have.

As the lake began to heat up in May, the mussels started dying and loosening their grips on the tunnel walls.

In quantities that could fill the scoop of an earthmoving machine, they began washing along the 300,000-gallon-per-minute torrent rushing into the cooling system -- clogging it.

To solve the problem, that torrent would have to be stopped, which would require the entire plant to be shut down -- a process that is extraordinarily expensive and time-consuming.

-- PLONK! (realaddress@hotmail.com), June 08, 1999

Answers

At least we finally figured out what kills zebra mussels!

-- Brooks (brooksbie@hotmail.com), June 09, 1999.

Thanks fo the post,

My heart pounds - I am pissed..... There is just ABSOLUTELY POSITIVELY NO EXCUSE FOR US TO NEED NUCLEAR POWER!!!! There, I feel better now. We as a society have become glutenous pigs when it comes to power and these kinds of amazing scenarios are the result (if we are lucky). Can you imagine, someone forgot to clean out the COOLING TUBES! Hey HOMER, didn't you clean out the cooling tubes? Duh... God please save us from ourselves.

Sorry to rant I just can't believe we have built this mess for ourselves and our children.

Mellowing out now,

Kristi <:

-- Kristi (securx@succeed.net), June 09, 1999.

It's always the "little things" that we tend to overlook that come back to haunt us later.

-- Tim (pixmo@pixelquest.com), June 09, 1999.