The Genius of Louis Pasteur

just a containment structure around the
steam collectors and headers, not
around the entire reactor. (This is like
putting the hood of your car over the
radiator part only.)
The Soviets went with this design in
the early 1970s because it was easier
for them than mass producing the more
technologically sophisticated light
water reactors used in the West. In
particular, their scaled-up graphite reactor
avoided the problem of producing
large pressure vessels. In addition,
of course, the graphite-moderated reactorcan
produce weapons-grade plutonium,
a fact about which the Soviets
have remained silent.
The Soviets put their first two 1,000megawatt
graphite reactors at a site
near Leningrad in 1973 and 1975, and
by 1982, they built eight more, which
produced at the time 64.5 percent of
all electric power produced by nuclear
plants in the Soviet Union. Today, there
are 17 graphite reactors, known as
RBMK-1000, and the Soviets have plans
for a 1,500 megawatt version.
From a safety standpoint, the Chernobyl
reactor is a "nightmarish problem,"
according to Robert Bernaro, director
of boiling water reactor licensing
at the Nuclear Regulatory Commission.
The engineering difficulties
are inherent in the use of the graphite
as a moderator, among other things.
U.S. reactors have what is called a negative
coefficient, which means that
when the coolant temperature goes up,
the reactor shuts down. In the graphite
reactor, if the coolant temperature
goes up, the reactivity goes up, which
requires the Soviets to have a variety
of special emergency measures to ensure
that the graphite does not ignite.
Bernaro, who was also quoted by
Diamond, commented on the question
of safety: "I'm unwilling to hinge
the acceptability or unacceptability of
U.S. reactors on what the Russians do
or do not do. If we can learn something
from what the Russians have done
or have not done, fine. . . . But in the
meanwhile, I think that our primary attention
ought to be on our own reactors."
Antinuclear Advertising
That the New York Times's Diamond
crafted his article solely to make the
antinuclear case is amply demonstrated
by the accompanying full-page ad
Continued on page 60
WHAT THE EXPERTS SAYl
An Interview with
Dr. Joseph M. Hendrie
Joseph M. Hendrie, former chairman
of the U.S. Nuclear Regulatory Commission,
is now a consulting engineer.
He served on the NRC from 1977
through mid-1981. He was interviewed
May 5.
Question: How would you assess the state
of U.S. nuclear safety, compared to Soviet
safety systems?
The U.S. water reactors are simply
incapable of producing the sort of gross
release that has occurred in Russia. We
don't have the flammables in core that
would provide the kind of driving force
they had there in the fire. Our systems
are engineered with more extensive
safety provisions and we then encapsulate
the whole reactor system in a
very strong and tight containment
structure.
Another point is that after Three Mile
Island we made a very extensive reassessment
of the safety of U.S. plants
from all kinds of standpoints and all
kinds of accidents and found it appropriate
to upgrade a number of areas.
We have concentrated attention on
operator training and expertise and on
a drive to achieve real excellence in
operation at all U.S. plants. This is reflected
in the industry efforts as well as
in the regulatory incentives.
Furthermore, we undertook after
Three Mile Island, a very extensive upgrading
of the ability both on-site and
off-site to take emergency measures in
the event of accidents. I think those
provisions are particularly notable
against the background of the Russian
accident.
Question: Most of the material written
in the 1970s on the Soviet safety question
indicates that their attitude toward safety
is very different from that of the United
States. They are very scornful of the
Americans for spending so much money
on what they consider unnecessarily redundant
safety systems.
I think that may have been the attitude
in some quarters earlier on. My
impression is that in the last five, six,
or seven years there has been a move
in the Soviet Union toward safety standards
and arrays of safety systems in
the plants more like the Western standards.
Those are reflected, for instance,
in the designs of the new PWR
[pressurized water reactor] line, 1,000megawatt
line, which does have emergency
core cooling systems similar to
U.S. designs and does have containment.
Or at least the outline drawings
I've seen for what they were regarding
as their standard 1,000-megawatt PWR
did have a containment that looked
very much like a standard U.S. reinforced
concrete prestressed containment.
So I think there's been a move
in the Soviet Union in thelastfewyears
for reactor safety standards more nearly
like those in the Western world.
But, of course, these graphite machines
are in many ways a design and
reactor concept from an earlier time. I
think they have a number of features
about them which are not desirable
from a safety standpoint.
Question: It's curious, given this, that the
Soviets claimed in some of their publications
that the graphite reactor was actually
safer than the PWR.
I think in part that grew out of a concern
on the part of the Soviets that was
really one of the bases for the effort
they put into the graphite machines: it
was a long time before the Soviets were
confident about their ability to fabricate
large pressure vessels of the necessary
quality for a large reactor. That's
really a central reason why they went
into that pressure tube design—to
avoid having to fabricate very large size
reactor vessels.
Remember that the 440-megawatt
PWR, which has a substantially smaller
pressure vessel, and which has been
Continued on page 67
Nuclear Report FUSION September-October 1986