Powerful Presence : Nuclear, Gas Facilities Energize North County

Inside the Encina Power Plant in Carlsbad, bicycles are casually parked everywhere.

The bikes are essential for employees to get around the plant: It is a block wide and a block-and-a-half long.

The whine of fans and churning turbines in the plant combine with the hum of electric monitoring equipment, heat blasting furnaces and clanging metal. Most workers are dressed casually, in blue jeans and running shoes.

A few miles up the coast, at the San Onofre Nuclear Generating Station, there are no bicycles.

Concrete encased nuclear reactors are sited in an imposing jumble of hoses, ladders, security checkpoints, green-glass guard towers, barbed wire loops, catwalks and cranes. There are occasional glimpses of employees wearing protective jumpsuits and signs warning of radioactive material.

Tremendous amounts of power are produced at the two North County power plants, each planted on the ocean’s edge. One is fueled by the burning of natural gas and oil; the other by controlled nuclear reaction.

The plants give North County what are probably its most dramatic man-made landmarks: the cherry-light topped domes at San Onofre and the box-shaped, steel-facaded plant and 380-foot-tall tower at Carlsbad.

The Encina plant is owned by San Diego Gas & Electric; the San Onofre plant is owned primarily by Southern California Edison, but in part by SDG&E.;

Homer Simpson, the bumbling nuclear plant worker from the television show “The Simpsons” is not a popular figure among the 2,300 men and women who work at San Onofre.

In one episode, set in a San Onofre-like plant, Homer drives a forklift into barrels of radioactive materials.

“The writers for the Simpsons were here for a tour a couple of months back. . . .They came here for a general impression,” said engineer Eugene Cramer.

Cramer pointed to a nearby door and said in dismay, “They made it look as if the doors at the plant were rolled-up garage doors.” The door in question appeared, in fact, to be a formidable combination of bank vault and submarine hatch.

“What I would have liked is for them to have written in a serious way about the serious job people do here for a serious purpose,” Cramer said.

David Barron of Southern California Edison’s corporate communications department wasn’t amused by the portrayal in the Simpsons either. “You know, there’s a poster of that guy hanging around here--with a bar across it. It says ‘No Homers Here.’ ”

When nuclear power station workers aren’t warding off questions like “Do you glow in the dark?” or “Do you get your tan indoors?” they battle other misperceptions.

“People think of nuclear power as a mysterious, freaky, unusual thing,” said Cramer. “Actually it uses appropriate technology, proven by time and physical principles as old as the hills.”

Although San Onofre does not have the ominous reputation associated with some nuclear power plants--like Three Mile Island, Diablo Canyon, Seabrook or Shoreham--it is not free of controversy.

Last year, a 15-year, $46 million study of the station’s environmental impact was completed. It cited a 200-acre reduction in the size of the San Onofre kelp bed as among the adverse effects of the plant. After its release, the study was criticized by one of its three authors as inadequate. Biologist Rimmon Fay disagrees with the conclusion that nearby sea life is not being significantly harmed.

The biggest recognized danger from a nuclear reactor is uncontrolled release of radioactive material. Nuclear power plants are layered with security and safety precautions designed to prevent that from happening.

Once a year, a full-scale emergency drill is staged at San Onofre. About a dozen groups--ranging from the county emergency preparedness office to the Red Cross--participate in the drill. There is a 12-mile radius around the plant designated as an emergency planning zone. Some 900 Marine housing units fall within the zone.

Inside the gas-fired Encina plant, the 10-story furnace and boiler can be glimpsed through small portholes. Violet and yellow flames seem to press against the medallion-shaped windows. The fire is burning at temperatures of 2,500 degrees.

Those flames are fueled most of the time by natural gas from Oklahoma or Texas, said John Pruyn, an executive at San Diego Gas & Electric. About 7% of the fuel is low-sulfur fuel oil from Indonesia or Alaska. Natural gas arrives at the plant via underground pipelines. The oil is delivered by tankers that anchor off Carlsbad.

In the 36 years the plant has been operating, only the smallest spillage has occurred, according to Pruyn.

Once a year, the plant stages an oil containment exercise to prepare it to deal with an oil spill, should one occur.

A staff of about 125--engineers, mechanics, maintenance workers, and control room technicians--keeps the Encina plant in operation 24 hours a day.

The power plant, switchyard and other property covers about 800 acres, including the adjacent lagoon. Encina uses water from the Agua Hedionda Lagoon to cool its interior pipes.

Pruyn shouts above the roar of the plant as he explains how electricity is generated.

“It’s like a giant tea kettle,” he said.

The tea kettle analogy works this way: The furnace heats purified water, the water turns to steam, the steam rises through pipes to the top of the boiler to a drum. The drum pipes the steam to a turbine.

The steam, pressing at about 1,900 pounds of pressure per square inch, spins the blades of a turbine (there are five of them at Encina).

The turbine operator shaft, spinning faster than the speed of sound, creates a magnetic field. Electricity is generated by rotating this magnetic field between thick coils of heavy wire.

The electricity then rides through two-inch thick cables out the side of the building, through the switchyard and to neighboring substations and then to local transformers (there is about one on every block), and from there to houses and businesses.

Nestled between the Camp Pendleton Marine Corps Base and the Pacific, San Onofre’s three nuclear reactors straddle 257 acres leased from the Department of the Navy.

Two reactors are under concrete domes; the other is in an earlier-style, flat-roofed, cylinder-shaped building.

The reactors are fueled by uranium pellets that arrive by truck. The fuel is mined, refined and purified by the federal government. The uranium reaches a high level of radioactivity only after it is in the reactor and the chain reaction begins.

The tea kettle principle in use at the Carlsbad site is, in many ways, also the axiom in action at San Onofre.

The difference is in how the water is brought to a boil.

Nuclear heat within the reactor core is developed when atoms of uranium fuel are split apart. This fissioning process, as it is called, is limited by control rods. When control rods are inserted the chain reaction is stopped; when they are withdrawn, that reaction resumes again.

In addition to producing huge amounts of electricity, the process produces radioactive waste.

High-level radioactive waste is stored at the plant in fuel storage pools made of reinforced concrete and steel.

Items such as jumpsuits, towels, gloves and shoe covers worn by workers become contaminated with low level radiation. The contamination typically occurs when maintenance, surveilance personnel, mechanics or craftsmen work with electrical components or piping inside the reactors.

The protective garments are run through a washing machine equipped with a filter designed to collect radioactive particles. If the radioactivity cannot be washed out, the items join other low-level radioactive waste material that is packed in barrels and shipped to Beatty, Nev., where it is buried.

“People flip that switch and they never realize the amount of expertise, fine tuning, and technology it takes to produce a watt,” said Pruyn of SDG&E.;

Utilities measure and bill consumers for electricity by kilowatt hours.

One kilowatt hour, which costs about 9 cents, is equivalent to one 100 watt light bulb illuminated for 10 hours. A typical household uses about 500 kilowatt hours a month.

Despite the power it draws from San Onofre, Encina and a third plant in Chula Vista, SDG&E; must still import almost half its power. The utility serves 900,000 households in San Diego County and about 50,000 in southern Orange County.

Nearly two years ago, a merger between SDG&E; and Southern California Edison was proposed. The merger, if approved, would create the nation’s largest electric utility, with 4.8 million customers. State and federal regulators won’t finish their reviews of that proposal for several months, but many observers believe that some version of the merger will eventually be approved.

Meanwhile, North County’s two giant power plants continue to produce electricity for consumers in this area and beyond.

Last year, Encina and San Onofre combined produced 17.7 billion kilowatts.

Which is enough to boil the water in a lot of tea kettles.

ENCINA POWER PLANT

Where: Carlsbad

Owner: San Diego Gas & Electric. Supplies power to San Diego County and parts of Orange County.

Employees: 125

Fuel: Natural gas, fuel oil

Output: 960 megawatts at peak capacity. Last year, 2.7 billion kilowatt hours produced

Built: 1954

SAN ONOFRE NUCLEAR GENERATING STATION

Where: Camp Pendleton

Owned: Southern California Edison (80%) and SDG&E; (20%). Supplies power to users throughout Southern California, including most of Orange County and parts of Ventura County.

Employees: 2,300

Fuel: Uranium

Output: 2,650 megawatts at peak capacity. Last year, 15 billion kilowatt hours produced

Built: Construction began on Unit 1 in 1964, completed in 1969. Unit 2 began in 1974, completed in 1983. Unit 3 began in 1974; completed in 1984.