BOB O'NEILL cannot see the beast. He cannot hear the beast, touch it or smell it, but he knows it is there because it keeps tweaking the meters on the bank of refrigerator-door-sized Sony monitors stretched out in front of him.

Bob, whose position in front of a dizzying array of power-plant readouts draws an inescapable comparison to that Hollywood control room where everything goes to hell in "The China Syndrome," is only here to baby-sit the beast. He watches it work, lighting up whatever gets lit out here in Klickitat County, a half-day's cattle drive above the Columbia River Gorge.

"It's a living, breathing thing," Bob says.

The cage for the beast: More than 20 miles of plastic pipe connecting subterranean "wells," then funneling into this plant, the nicest and cleanest one he's worked in, says Bob — who once baby-sat a beast of an entirely different order downriver at the former Trojan nuclear plant.

This beast is mildly fickle, changing in intensity from season to season and even day to day. Fact is, a trained eye can watch it wax and wane and, based on that, predict the weather. (Yes, yes, trained eyes also could predict the weather with a common dime-store barometer, rather than the sensitive instruments on a $70 million gas-turbine plant. But that's beside the point.)

No dime-store barometer can do for local humans what the beast is doing right at this minute, and should keep doing, 24/7, for a century: Providing the electricity to light tens of thousands of homes.

The beast is an invisible army of bacteria, hard to fathom in size and scope, churning away beneath the surface at Roosevelt Landfill, one of the largest and most high-tech solid-waste facilities in North America. The bacteria eat garbage and emit methane gas, which is sucked into Bob O'Neill's power plant, constantly, under a very slight vacuum.

The beast, in some ways, is the future. And the best thing about it, for people in Klickitat County, is that nobody down here has to feed it. All of us loafer-wearing westsiders do that for them. Every time we take out the trash.

THIS TRASH-TO-GAS concept — part of the raison d'être for the Roosevelt plant since its inception in the late 1980s — really is sort of a miracle. As you watch, it's tempting to suspect it's too good to be true.

The power plant is a nondescript block building, one of the few structures at the landfill, about an hour away from anywhere. Behind the building, amid the Rube Goldberg network of piping, rise two large emission stacks. Aha, you think: The business end. Flip side of the shiny coin.

Yet as the plant hums away, injecting, at that moment, 17.6 megawatts of power into the Bonneville Power Administration grid — enough to power more than 15,000 homes — out of those stacks comes ... nothing. No smoke. No discernible fumes. No smell.

"There's a heat signature," says site manager Kevin Ricks, "and that's it."

A bit of steam does rise nearby, from one of the plant's boilers. It's about what you might see when pulling the lid off a household rice cooker.

Sensors are on watch for stuff you can't see. But this is about as green as energy production gets. The newest methane-burning electrical plants actually strip pollution from the air by disposing of methane, an extremely potent greenhouse gas. Nothing goes to waste here; even the heat generated as exhaust by huge gas-burning turbines is recaptured, making steam that turns its own generator crank.

The plant is the second built here under a partnership between the local public utility district and Republic Services (previously Allied Waste, before that, Rabanco), which runs Roosevelt. It went online earlier this year, replacing a smaller, less-efficient plant.

The power generators were a cornerstone of this place from the get-go. Roosevelt — get this straight — is not a dump, which is a hole in the ground into which garbage is strewn, left to rot and, ultimately, contaminate the local water table.

"Dump is a dirty word in our business," says Art Mains, Roosevelt's environmental manager. Easy joke, serious point. "This was designed as a purpose-built facility from day one."

When they opened bidding for a gigantic regional landfill two decades ago, Klickitat County commissioners had three goals: Provide living-wage jobs where the local economy was overdependent on timber and aluminum. Produce power. And create a final resting place for much of the Northwest's trash.

Twenty-two years after accepting its first container-loads, Roosevelt appears to have succeeded. Power is flowing, and even as the nearby aluminum smelter is dismantled, Roosevelt sustains 170 family-wage jobs.

"I really don't know how we would function without it," says Ray Thayer, a county commissioner for 16 years.

Roosevelt's "tipping fees" and taxes contribute between $7 million and $8 million a year to the county's $25 million budget, he says. Without it, county employee roles would be cut by half.

Twenty years ago, a few local residents protested the notion of their homeland becoming the Northwest's regional garbage can. Today, Thayer says, "I never hear one word about it."

The most angst caused by the landfill, he says, comes from potential customers who tour the facility and are struck with garbage guilt, asking, "Are you sure it'd be all right for us to send all our garbage to your county?"

Thayer just smiles and shoots back: "It sure would!"

TO THE SHORT list of life's certainties — death, taxes — add this one, courtesy of Art Mains: "The garbage is going to keep coming."

Despite the best efforts at recycling, people produce trash. Republic Services, which also runs one of the nation's largest recycling facilities, in South Seattle, has both ends covered. The more recyclables it diverts from the waste stream, the more room it has at Roosevelt to accommodate population growth — and all the discarded Silly Slides, inflatable Santas and other stuff that comes with.

The beast beneath Roosevelt does not consume all of Western Washington's trash. Some of the garbage from King County and all garbage from the cities of Seattle and Portland is similarly disposed of at Columbia Ridge Landfill near Arlington, Ore., right across the Columbia River. That landfill, run by industry giant Waste Management, is of comparable size and has its own, smaller methane power plant.

Roosevelt swallows up most everything else from the region: Snohomish County, the largest customer, shipped nearly 433,000 tons last year. Other major customers include Whatcom, Skagit, Thurston, Island and Jefferson counties, most of southwest Washington and the Olympic Peninsula, and portions of Eastern Washington.

Spokane County ships incinerator ash here, and trash arrives from Oregon, Idaho, Alaska, even Guam. Every scrap of refuse from the self-proclaimed uber-green alpine village of Whistler, B.C., gets entombed here, too.

In all, the landfill last year digested more than 2.1 million tons of garbage — down, during the recession (the economy is a reliable indicator for garbage volume), from 2.4 million tons in 2008.

Ninety-seven percent of it arrives in steel containers on trains mustered in Everett, Centralia and Seattle. (Would it spoil the romance to know that some of those train whistles we hear at Safeco Field are mile-long strings of rotting garbage?)

Two Burlington Northern Santa Fe trains per day pull into the yard at Roosevelt, which sits hard by the Columbia about 130 miles east of Vancouver. Each carries 125 to 150 containers. Each of these 48-foot boxes holds 28 to 32 tons of compressed garbage.

At the Roosevelt siding, containers are unloaded onto semi trucks, which make their way across Highway 14 and three miles up a special "haul road" to the landfill. There, the containers are tipped, emptied, then returned to the rail yard. It takes about four hours to unload a train and turn it around to head back west — usually hauling fruit, grains or other cargo.

Yes, in separate containers.

HOW BIG a pile does all this trash make? If you could see into Roosevelt with X-ray vision, the accumulation would be mind-blowing.

Roosevelt lies in a natural bowl on the Horse Heaven Plateau, and the landfill's daily diet of 6,000 to 9,000 tons of trash is dumped in 200-foot-wide "cells" — the only part of the landfill that's ever exposed. After compaction by heavy equipment, it is covered with soil before nightfall to curb smell and discourage birds and rodents (none of which are in evidence here). The next day, the soil layer is removed, and dumping resumes.

The scale of it all is difficult to fathom: Roosevelt covers about 2,500 acres in all (think 10 Green Lakes). Its current dumping-permit area is 915 acres. And of that, about 360 acres is full or near-full, of garbage compressed in layers taller than a 15-story building. If just the permitted area is filled, the garbage would cover about 80 football fields with trash 140 feet deep. But all of that will be capped by a layer of earth that should be clean enough, in the end, to revert to grazing land.

"It's a construction project that never ends," says Mains, 43, who grew up in nearby Bickleton and studied engineering at the University of Washington. "That creates a little job security."

Mains is way ahead of the next question: Even though it's removed from sight, won't all this trash leave a toxic legacy?

Yes, but no. The garbage is being entombed, he notes, in a place that couldn't be designed more perfectly for trash. The site gets about 9 inches of rain a year — one-fourth that of Western Washington. The land is separated from the water table of the Columbia River by hundreds of feet of solid basalt. Atop that is a natural layer of clay more than 300 feet thick — 10 times less water-permeable than federal regulations require for engineered clay liners beneath landfills.

And atop that, designers have exceeded federal regulations with an additional layer of clay, topped by a seamless composite liner that traps, and recycles, any leachate. The water is collected in pipes and recirculated to promote bacterial growth — and more methane gas. All feed for the beast.

Sensors monitor the water. But if the liner ever failed, Mains says, it would take 15,000 years for groundwater to reach the river, thanks to the local geology.

The landfill itself is so well-hidden by the ridgeline, most people drive right by it on Highway 14 without ever realizing it's looming right over their shoulders.

IT RAISES a question for any nature-loving Northwesterner with built-in recycler's guilt: Is all that invisibility bad? Should everyone whose trash comes here be required to spend a day seeing what gets buried by giant earth movers with spiked metal wheels as large as Smart Cars?

Perhaps. Here is what they would see on this lonesome ridgetop, surrounded by massive white turbines that harness the incessant wind:

A lot of unidentifiable, already decaying organic material. Busted-up furniture. A plastic truck-bed liner. A TV stand orphaned by the flat-screen revolution. One kiddie wading pool, cracked. Numerous 5-gallon buckets, same. Various plastic patio furniture. A Coffee Mate jug. Various forms of insulation. A queen-size mattress, extra-well-used.

"That pile, right there, that's yesterday's daily cover," Mains says, pointing to a layer of soil to the east.

Sticking out from it: A red sofa pillow. A child's shoe. Chunks of foam rubber. A Papa Murphy's Pizza menu. A bowling shoe. Styrofoam takeout containers, lots of them. One big Burger King soda cup. Cookie wrappers. A Darigold chocolate milk container, 2 percent.

A water truck moves in and out, spraying to keep the dust down as two massive, D-10 Caterpillars roar through the trash.

The rubber tongue of a flip-flop. A shredded blue tarp. A cherry yogurt carton. A child's soccer cleat. Oreo wrappers. Latex gloves, numerous. Brown shag carpet. Green garden hose. A broken laundry basket

And seemingly everywhere: plastic grocery bags, dancing on the wind and, eventually, snagging in large mesh fences erected along the ridgelines specifically for that purpose. Every night, a squad of "garbage pickers" walks the line and pulls them off. End of the next day, they're baaack, by the hundreds, some of them seeming to rise from the dead through the loose soil, yanked free a fraction of an inch at a time by the wind before achieving enough exposed critical mass to set sail one last time.

It's enough to make anybody watching Roosevelt's stunningly efficient, relentless enterprise leave with mixed feelings about whether it should ease, or heighten, trepidation about one's impact on Mother Earth.

Perhaps it's more instructive to simply look at where we are today in the trash world, and where our grandparents have been.

Only three generations ago, in the 1920s, Josie Razore, one of the forefathers of Rabanco, the company that built this landfill, picked up garbage in Bellingham, trucked it to barges — and then at night, hauled it out and dumped it straight into Puget Sound. And nobody thought twice about it.

Today, some people's very big ideas are turning the same trash into clean power. But there's still plenty of room, Art Mains points out, for little ideas to make a difference — both at home, and down here where everything winds up.

Watching those plastic shopping bags swirl on the winds, Mains frowns and gestures at a hillside alive with waving white — flags of surrender for even the most high-tech landfill.

The beast beneath will, over time, eat just about anything. But even insatiable bacteria have their limits.

"That slope was completely clear yesterday," he laments.

The guy is an engineer and takes no position on shopping-bag bans. But Mains does have a simple request for all those folks at the other end of the garbage trains who insist on using the bags and then tossing them:

"Just tie a knot in them," he pleads.

That, literally, is the least you can do.

Ron Judd is a Pacific NW staff writer. Mike Siegel is a Seattle Times staff photographer.