By Val Sears, Science

Toronto Star
Sunday, July 18, 1982

We're spending $140 million a year so we'll be ready when the world wants nuclear power

CHALK RIVER - Curiously enough, the federal government is spending more than $100 million a year figuring out cleverer ways of boiling water.

Oh, they've got the basics down about right - you burn wood or oil or gas or coal or uranium and that heats the water.   With the steam you drive a turbine and that produces electricity.

But most of these fuelish things come out of the ground and they won't last forever.   And we'll still need energy.

So what Atomic Energy of Canada Ltd. (AECL) is doing in this woodland setting down by the Ottawa River is dreaming up some new fuels - thorium, for instance - that will help keep us warm in the light until fusion or maybe solar energy comes in, perhaps in the next century.

Atomic furnace

Of course, they also produce radioactive isotopes for medicine, gamma ray scanners to detect knots in logs and accelerators that shoot photons for research.

And they'll soon have a dandy little atomic furnace that will heat your apartment building in winter.

But most of the $140 million in tax money spent here and at a smaller research establishment at Whiteshell in Manitoba is devoted to Candu, the all-Canadian nuclear reactor, its fuel, its efficiency and its waste.

Why?

The technology is well-known, hardly anyone is ordering nuclear power stations anymore and, last time they were asked, only a bare majority of Canadians figured the power that levelled Hiroshima was such a good way of making electricity anyway.

The simple answer, the theology of Chalk River, is: Someday, after the oil glut and the coal pollution, the world is going to turn to nuclear power in a big way again and we want to be ready.

More to the point, it is the Candu (Canadian Deuterium-Uranium) scientists believe will be the ultimate winner.   The first six best performing nuclear reactors in the world are operated by Ontario Hydro and they're getting better all the time.

Pickering plant

"If we'd only had the Pickering plant operating 10 years earlier," mourns John Slater, head of Chalk River's Advanced Projects Division, "we would have captured a large share of the world market."

As it is, 28 Candu reactors have been sold or are on order, with five multi-unit plants in Ontario, a single reactor in Quebec, one in New Brunswick and the rest overseas.

"That's still about 5 per cent of the market," says Archie Robertson, Chalk River's assistant administrator.   "How many other Canadian products have captured 5 per cent of the world market?"

By 1990 half of all Ontario's electric power will be generated by Candus and there could be more for export.

"And it is no accident," says Robertson, "that there has not been an accident."

Yet there is an air of unreality here and in the community of Deep River, 200 kilometres northwest of Ottawa, six hours by car to Toronto. It is Brigadoon, for 5,500 people.

On weekends, the river is alive with sailboats, the Deep River Players play, the Arts and Crafts Society paints and something called Theop gets everybody into books and live theatre.   The Thing is playing at the tiny local theatre and a heavy metal band called Pressure blows everyone's mind at the motel.

There is no Three-Mile Island, no China Syndrome, no nuclear protest marches, no sense there is anything wicked or dangerous about splitting the atom to power hair dryers.

"The anti-nuclear people are simply a vociferous minority using the nuclear issue to effect social change," says Robertson. And that's that.

In general, Canadians seem to agree that nuclear is the way to go - but not by much.

Since 1978, only once has nuclear lost majority support in the Gallup poll.   That was in 1979 when, after the Three-Mile Island accident in Pennsylvania, 49 per cent of Canadians thought nuclear power was not such a good thing, compared to 39 who were in favor of it.

The last poll, in November 1981, showed 42 per cent of Canadians in favor and 36 opposed with 22 don't-knows.

Meanwhile . . . back among their aging reactors - the latest of the two was commissioned in 1962 - Chalk River's 2,300 scientists, engineers, technicians and office workers remain dedicated to the future of fission.

Their establishment, guarded by fences, monitored by TV cameras, everyone wearing a radiation detector, is a sprawling collection of old wooden, "temporary" buildings, sleek laboratories, metal working shops and cavernous, metal-lined rooms where bolts of lightning arc from the walls.

There are deep pools of water, glowing softly blue (the Cerenkov radiation) from spent uranium fuel rods stored at the bottom.   In the giant reactor rooms, students from Guelph and McGill perform abstruse experiments with streams of gamma rays led out from the hellish heart of the radioactive core.

All this grew out of experiments in Ottawa between 1940 and 1942 when small amounts of uranium oxide were stuck in a wooden barrel and surrounded by paper bags full of coke to see how many neutrons from the uranium could be captured.

Later, a laboratory was established in Montreal staffed by some brilliant - but by all accounts, quarrelsome - scientists determined to test the theory of fission: that by splitting an atom of U235 with a neutron, the nucleus breaks apart, the parts collide with other atoms and heat results.

Chain reaction

If there are enough collisions and breakups, the process will produce a chain reaction and go on for a long time.

The American scientists at Los Alamos made the whole process work very quickly, producing an atomic bomb.   In Canada, the reaction was slowed down by a blanket of heavy water to produce a controlled reaction.

The decision was made to build the reactor - zero energy experimental pile (ZEEP) - out in the boonies.   So a plant, Chalk River, and a community, Deep River, were built way out by the Petawawa River.

The reactor went critical, that is began operating, on Sept. 5, 1945.   It was the first time a nuclear reactor had been operated outside the United States.   Reactors have been producing energy at Chalk River ever since.

Two things distinguish the Candu reactor: It operates on natural uranium and fuel can be added while it is still under full power.

In effect, while most other reactors enrich the uranium and use ordinary water, Canada uses ordinary uranium and enriches, the water.

Enriched uranium reactors have to be closed down to be refuelled and they use uranium that is nasty enough to make weapons from. Canada's uranium is really quite nice.

But there is one singular disadvantage to Candu that is particularly troublesome to the International Atomic Energy Agency (IAEA), charged with inspecting signatories reactors to see that none of the fuel is diverted to weapons.

Because Candu is not shut down to refuel - and the spent rods removed can be processed to remove the weapons-grade plutonium - inspectors have a tough time getting a close look at what's going in and coming out.

Activated cameras

So Chalk River scientists have come up with a "safeguards program," a collection of geiger counters, film cameras activated by any flicker of movement, television surveillance and wave detectors that can tell if a fuel rod, underwater, has been moved.

Once this tamper-proof equipment is in place, it would be almost impossible to hide fuel rod diversion.   Although Chalk River scientists add, ruefully, that India didn't bother to hide its diversion of fuel to weaponry at its Candu reactor.

But the biggest safety challenge at both Chalk River and Whiteshell - costing 30 per cent of AECL's budget - is research into permanent storage of dangerously radioactive fuel rods.

Since the first reactors began operating in Canada, all the spent fuel has been packed in bundles of metal containers and stored under 12 metres of water.   There are two reasons: Less than one per cent of the energy in the rods has been burned and more may need to be recovered some day; and, as the fuel has to be safely stored for thousands of years, AECL wants to be sure it's going to do it right.

The underwater storage is good for at least another 50 years at current fuel consumption, so there's plenty of time for the research.

Still, AECL figures that, in theory at least, they have the waste-management problem beaten.

The Canadian shield, that massive rock plain in Canada's North, has various solid rock plugs, called plutons, scattered throughout.

Geologists are now examining these plugs to find which have the fewest cracks and just how long, in the soundest ones, it would take water to seep to the surface.

When, sometime in the next century, a decision is made to bury the fuel, bore holes 1,000 metres deep will be drilled in the plutons and a chamber hollowed out.   The fuel, in containers, will be buried in the chamber floor and backfilled.   Finally, when the vaults are full, the whole things will be sealed.

Scientists say this storage method will keep the fuel safe for a geological age, long enough for the fuel's radiation to die.

There are still risks.   The site could be disrupted by earthquakes, although the Canadian shield is stable; thermal radiation could create cracks - that's what the research is about now - or there could be intrusion by man.

"However," says an AECL study, "even if penetration (by man) is made, it is not likely that a society with technology capable of drilling to such depths would not be able to recognize the hazard of radioactivity and take remedial action."

AECL plans an underground research laboratory to study waste storage at Lac du Bonnet in Manitoba.

At Chalk River, only about one-third of the budget exclusive of waste disposal studies - is devoted to Candu and that, mostly on improving valves and plumbing.   The remainder goes to more advanced research.

A major task is to study ways of making thorium - a relatively abundant substance - fissile, that is capable of sustaining a nuclear reaction.

Thorium can be combined with a small amount of fission material - say plutonium from the spent fuel rods - and then behave just like uranium.   A thorium cycle in a Candu reactor would be almost a "breeder." It comes close to producing as much fuel as it consumes.

"With a thorium cycle," says physicist Slater, "we would have sufficient fuel for a century or more."

Using electricity

Slater and his group are working with a proton accelerator to devise a unique means of making thorium fissile using electricity as the power source rather than plutonium.

At the same time, Chalk River scientists are keeping their fingers in fusion power research, a technique that requires fusing atoms rather than fissioning them to produce heat, using abundant hydrogen.

In another part of the forest, nuclear physicist John Hilton [sic - should be John Hilborn] is working on an improved version of SLOWPOKE (safe, low-power, critical experiment).

This very safe, low-power reactor can be used to heat an apartment or a supermarket.

Even anti-nuclear researcher Norm Rubin of Energy Probe is at least lukewarm about the early SLOWPOKES.

"I'm fairly relaxed as far as SLOWPOKES-1 and -2 are concerned," he says. "They're nice, well behaved little reactors . . ."

While scientists and engineers are working on more abstruse projects, Chalk River is running a tidy little business in nuclear spin-off products, from isotopes to valves, from brain-scanners to reactor cleaning technology.

The Crown Corporation earns $30 million a year from its products, its research contracts and its licensing arrangements - enough to keep the establishment ahead of inflation.

Chalk River men like Archie Robertson, who came to AECL from the British Atomic Energy Authority in 1957, have an almost theological faith in atomic power.   The current turndown in nuclear enthusiasm is simply a blip on the long-term energy screen.

"Decisions not to buy nuclear power plants are purely economic," he says, dismissing any suggestion they are related to public concern about safety or the efforts of anti-nuclear power lobby groups.

When the economy turns up again - and it has to or all bets are off anyway - the demand for nuclear power will return," he says. "The public wants it."

"Why Ontario alone is bringing on line the energy equivalent of a Hibernia oil field with additions to the Pickering and Bruce plants.   Think of the fuss that would be made if we found a Hibernia oil field in Ontario. But no one celebrates this."

So they go back to their towering reactors, their accelerators, their thorium cycles . . . their sailboats.

Canada's nuclear Brigadoon will be discovered again someday, they're sure, and they want to have a big warm, glowing welcome ready.

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