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SPEAKER 1: Gentlemen, this is Mr. George Soya. He's the resident engineer assigned to the plant, and he'll briefly describe the operation on this overlay that we have. And from there, I will take you through the facility and try and explain it as we go along.

GREG BARRON: Chicago's Northwest incinerator plant in operation for about three years now is said to be one of the largest and most efficient solid waste disposal systems in the world. The plant receives raw trash from city trucks then burns the trash and uses the heat to convert water to usable steam. The steam can then be used to generate electricity or as it's proposed for the Chicago plant, it can be piped for sale to nearby industry.

The plant's chief engineer said the energy crisis is driving the price of steam upward. This he said means that if current negotiations are successful, a local food processor will buy the steam at a price high enough to offset much of the plant's operational cost. With this in mind, we set off on our tour of the plant.

GEORGE SOYA: We're overlooking incredibly deep pit into which large packer trucks are dumping tons and tons and tons of refuse obviously have been picked up just recently and coming in from the street. The sound you're hearing are these large conveyors running back and forth the length of a long pit room.

Right in front of us now, two giant scoops have come up holding what must be five tons of trash, trash bags. I have been asked to stand back. It makes one dizzy. Just to look over the side and see the pit, the bottom of the pit where the trucks are dumping the refuse, it must be hundred feet down. Could it be? I think it could.

We've just been told that in heaping these piles of trash, they're being prepared to go into a giant hopper. At that point, they'll go on a conveyor belt into a burning grate. Truck after truck after truck backing into the area and opening up the back side letting loose its load of garbage.

The place smells very foul, I must say. It smells like the bottom of the rankest trash and garbage can I've ever smelled. But I understand here in Chicago, all these men are unionized and very well paid for it. I must say one would have to be. They've piled this up into large mounds. Now, where will it go?

SPEAKER 1: Well, the reason for that is that they make room for the trucks to dump down there as they come in. Otherwise, you would have to dump on the floor instead of into the pit. So the crane operator will make his lifts and pile up the material at each end of the pit. Then after the trucks are through dumping, he starts feeding these hoppers from these mountains that you see up here now.

GEORGE SOYA: And the material goes from the hoppers to the burner?

SPEAKER 1: Down into the furnaces, yes. Into the boilers.

GEORGE SOYA: What is this area we're entering here?

SPEAKER 1: This is your stoker floor now. You see the hopper up here?

GEORGE SOYA: Oh, the hopper is above us now. And these are the burners?

SPEAKER 1: No, these are the rams. The stoker rams that feed the material onto the burning grate.

GEORGE SOYA: The area we're in looks like a pipe fitters dream. There's what appears to be miles and miles and miles of pipes presumably carrying steam. As we've just heard, this area is the area where large hydraulic rams, as they're called, are called into action to push the material that has come down from the hoppers, which are now above us, into the actual burning grates where they'll be ignited. All right, we're on our way down again, down to a lower level.

This area, again, is other pipe fitters dream. A maze of tubing pipes, conduits, blowers. If I understand correctly, the machinery on this level is designed to blow air into the fire area to improve the combustion of the refuge which is actually burning in the burners. Now, apparently, these fans are driven by steam turbines. That steam, of course, coming from the steam generating capability of some of the burners.

SPEAKER 1: What you're seeing on the inclined plane here is what you showed you in the drawing. This is the reverse reciprocating traveling grate which tumbles and rolls the waste while it's in the burning process, which of course, this one is shut off at the moment.

GEORGE SOYA: Now we're looking into the inside of a burner.

SPEAKER 1: That's right.

GEORGE SOYA: That is--

SPEAKER 1: And we're about--

GEORGE SOYA: About a 4 foot square door.

SPEAKER 1: --to get out here and look at one that's actually working.

GEORGE SOYA: There's a small peep hole that we're gathering around now as we watch the actual flame in the combustion chamber where the refuge is being burned. Maybe a foot square heavy door here. I don't know if you can see this bright orange flame appears to be a very, very hot flame in a pile of trash burning away in this giant incinerator.

What temperatures are involved in this burning process here? How high do they get?

SPEAKER 1: We run between 16 and 1,800 degrees Fahrenheit.

GEORGE SOYA: That heat goes above us to the boilers.

SPEAKER 1: This whole unit is surrounded by water tubes. So the heat is extracted right here in the unit itself in the boiler. There's a drum above. And of course, this acts also as a means of generating the steam. So the whole area is enclosed in water tubes, which of course, creates your steam.

GREG BARRON: It takes only six men to run the entire operation. Most of the functions are run by remote control from a small room located in the bowels of the plant surrounded by the omnipresent maze of pipe, innumerable valves, and whirring turbines. The control room itself resembles Captain Nemo's bridge aboard the Nautilus, walls of gauges, dials, levers, and lights.

Obviously at home here, we found Chief Operator Walter Danning. He's in charge of monitoring every aspect of the plant's operation. At one point, he discussed the plant's pollution control device, a system which traps 97% of all gas and smoke.

WALTER DANNING: Over here, those four cabinets are controlled for precipitators. The smoke, which is being drawn out of the boilers, the gases, go through those electrostatic precipitators. The fine particles like carbon, sulfur, and so on are held by a charged wire system.

These systems are charged either positive or negative. So are the particles which are going out atoms are charged either positive or negative and being held by the opposite charge in the precipitators. This accumulates then into fly ash. And the fly ash is dropping down into hoppers. It's taken away by conveyors and being brought into ash discharges and put on the conveyor which goes up to the ash house where we separate all the refuse, the leftover.

But unburnt stuff coming out of the boilers falls in the same discharger and also falls on that conveyor belt. The conveyor brings it to a separator where the finer particles are being separated. And the heavy metal is going to a different hopper. Both hoppers, they have one hopper for the fine stuff which falls into one truck and the metal in another.

GREG BARRON: The recovered metal, like steam, is a saleable commodity. And the city sells it to recover a portion of the cost of operation. With the metal removed, the final remaining ash represents only 1/12 the volume of the same material before incineration. In the end, this relatively small amount of biologically inert ash is dumped in a conventional landfill. Eventually, it's said, even the ash will be commercially valuable.

SPEAKER 1: Don't touch the [INAUDIBLE].

GEORGE SOYA: Smells like garbage in here.

GREG BARRON: On Chicago's solid waste disposal system, this is Greg Barron.