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From: jgd@rsiatl.UUCP (John G. De Armond)
Subject: Terrorist attacks (was Re: More myth busting )
Message-ID: <2332@rsiatl.UUCP>
Date: 19 May 90 03:11:37 GMT

mdbomber@portia.Stanford.EDU (Matt Bartley) writes:

>The remaining trouble with terrorist threats is what one guy I talked
>to said.  He said all they have to do is set up an artillery piece on
>a nearby hill overlooking the power plant and start taking potshots.
>I don't see much of a way around that.  Just hopefully the military
>would have time to attack and destroy the terrorists before they
>nailed the reactor core.

Even this kind of attack is taken into consideration in the design of
a containment vessel.  The "standard missile" in most FSARs is a
60 ft telephone pole propelled by tornado winds to >100 mph.  This
delivers more ft-lbs on impact than even a cannon round.  The containment
is designed to withstand this missile with no damage and no breach of
containment.  It is also designed to withstand a direct airplane crash,
usually assumed to be a private plane.

An AP round would likely penetrate the outer containment wall and probably
even the inner steel containment vessel.  Loss of containment integrety
would result and probably some equipment would be damaged.  However,
for reasons mostly other than missile resistance, all equipment (reactor,
pressurizer & steam gens (PWR), recirc pumps (BWR), etc) is encased in
several feet of steel-reenforced concrete.  And in the case of the
reactor vessel, it is below grade and is covered with a missile/radiation
shield that is typically from 15 to 20 feet thick concrete.

As a point of interest, French terrorists fired (I believe it was) a
SAM-7 at the Super Phoenix breeder containment in France.  Nuclear
News published a closeup photo of the impact area.  It looked like someone
had dinged the concrete with a big hammer.  penetration was no more than
2 or 3 inches.  The concrete used in most containments is a special mix and
usually contains fly ash from coal burners.  This stuff is resilliant
and tends to deform rather than crack.  I've watched workmen bury the bit
of a jackhammer up in the stuff trying to demolish a structure and do
nothing more than make a hole.

Probably better targets for terrorist attacks would be the substation,
the emergency diesel generators or the cooling water intake structures.
These are much more vunerable and could conceivably case some minor
degree of core degradation.  This would likely manifest itself as
excessive leaky fuel cladding that results from overheating.


From: John De Armond
Newsgroups: sci.environment,
Subject: Re: Kudos to people really working to save the planet
Message-ID: <>
Date: 26 Jun 92 09:03:25 GMT (R. Cage) writes:

>I've never seen a missile shield on a cutaway view of an LWR
>containment, nor have I ever heard of them before.  35 feet
>is an awful lot of material to hide.  Just where is this located,
>is it standard, and why isn't it well-known?

It is well known among nukes.  A couple of places to look.  Any
FSAR. An old book perhaps still available in libraries "Systems
Summary of  Westinghouse PWR Nuclear Steam Supply Systems."
Every Westinghouse plant I've ever been to had the same framed
pictures of various large  systems components.  The containment
is one of these.  Westinghouse and B&W missile shields are quite
similar in design, involving typically two layers.  GE uses a
different design with the missile shield above the inner
containment.  BTW, the term "missile" used in this context
refers to any kinetic penetrator such as steam driven pipe
fragments, tornado-driven telephone poles, errant  planes and
the like. It does not necessarily refer to military missiles.
The missile shield is probably the heaviest thing handled during
refueling and is the reason for the huge polar crane at the top
of the containment.

>Solution to this:  HTGR's, LMBFR's and CANDU's.  All of these
>reactors can be piece-built rather than having huge pressure
>vessels which must be shipped from the factory, and could be
>built underground where they are safe even from thermonukes.
>One good site is the ex-Morton salt mines under Detroit.

It would require a site hundreds of feet below ground to reliably
defend against either bunker buster conventional or high yield
nukes specifically designed for deep penetration.  Not much of a
risk  these days.


From: John De Armond
Subject: Yack's daemons (was Re: Nuke Stupidity Rebuttal)
Message-ID: <>
Date: 28 Sep 92 07:39:09 GMT (victor yodaiken) writes:

>>My point is this:  I don't see how the kind of scenario you're so concerned
>>with can occur without some kind of release of highly radioactive material
>>from the reactor.  And as far as I know (this could be sheer ignorance on
>>my part, of course), the only way such a release can occur is when the
>>containment is breached.  After all, the *job* of the containment is to
>>prevent such a release, yes?

Let's take a look at what our resident armchair reactor engineer, yackadamn

>Well, that's the big question isn't it? What if a TMI style
>screwup happens at an older plant and when they finally start
>cooling it the reactor vessel splits open due to the loss of
>ductility associated with nuclear radiation,

If you're going to walk the walk, at least talk the talk.  The theoretical
problem is called Neutron-Enhanced Nil Ductility Elevation or simply
Neutron embrittlement.  Not a problem, of course, since a) all reactors are
now charged with fuel enrichments that minimizes neutron irradiation of
the pot and b) since the problem has been identified, all cooling water
including the passive accumulator cooling system is heated at all times
to a temperature above the theoretical worst case nil ductility point.  End
of problem.  As long as we're postulating, we can also postulate that the
same core melt that would set up the conditions for nil ductility failure
would also heat the pot hot enough to anneal out the neutron induced defects.
As long as we're postulating.

But let's assume for the sake of argument that the pot breaks.  What then?
Well either the bottom of the pot falls off or it stays partially in place.
If it falls off, it falls into the reactor sump and is cooled by the couple
of million gallons of water present.  If it stays in place, it is cooled
by the safety injection system, HPSI, LPSI, passive accumulator, concensate
cooling system, and/or river water system.  Yeah, we really do think
of these kinds of things when we design the multiply redundant safety

>suppose that the
>plant has a weaker containment dome than did TMI (which was
>especially strengthened due to the nearby airport),

No it wasn't.  All containment buildings must withstand the impact of
the largest known aircraft that would be flying in the area.  Most all
FSARs I've read use the 747 as the prototypical crasher.

>suppose that a
>venting valve from containment is stuck open,

Then the operator would simply close one of the other redundant valves
in the train.  All containment penetrations have two valves inside and
two valves outside, all in series and all designed to fail closed.

>or that there is a
>lightening strike and the operators lose instrument power,

Then the PWR plant would cool on natural circulation until power was restored.
Natural circ cooling is a test performed ALL PWRs.  BWRs are cooled by
first the HPSI and then the LPSI pumps.  Both are steam driven turbine
pumps that require no outside power to function.  I startup tested these
pumps at Browns Ferry NP, Unit III.  One of the tests performed is to
rack out the control panel power breakers and verify the pumps operate
normally and that all valves fail in the proper direction.  Note too
that all components including the heat sink are located inside the secondary
containment building so containment isolation does not affect their
operation.  (I've saved the definitions of the acronyms for later in
order to watch Yackadamn stumble over these new-to-him terms.)

>or that
>someone panics and opens a venting pipe

Then the SRO, the shift supervisor or the STA, all of which are licensed and
all of which are required to be in the control room at all times,
would override the operator and close the valve.  Since only the shift
supervisor, with the agreement of either an SRO or STA can override
a written procedure, "someone panics" would not happen.  If a sudden
fit of insanity should overtake one of the operators, the armed guard
posted at the entrance to the control room would remove him.

>or that the turbine cracks and
>sends a large metal fragment through the containment wall

A massive turbine failure with half the largest wheel escaping at best
velocity and penetration angle is a design-basis accident that is planned for.
Half the wheel is used because if a fragment constitutes more than half,
it won't be able to escape the shaft.  No credit is taken in the analysis
for the fragment penetrating the turbine casing (about 6" thick alloy
steel), the turbine building or aero drag during its trip.  Gee, Yack,
maybe you outta actually READ an FSAR sometime.
In other words, the turbine cannot penetrate the containment.

...., suppose
>its(sic) a BWR plant and the rods won't withdraw,

BWR rods insert from the bottom for shutdown, therefore your pretend is
irrelevant.  Assuming you knew enough to correctly phrase the hypothetical,
since each rod and associated drive in a BWR is a separate system, with
banks of drives located in at least 4 physically separated areas, and
since the rod insertion is a passive process driven by reactor pressure,
"rods" can't fail to insert.  A rod MIGHT.  "Rod Ejection" accidents,
as these events are known as, are planned for.

But let's pretend that something could happen to cause a massive failure
to insert.  The RO would simply lift the cover on the Standby Liquid
Control system  activation button and press it.  This would fire explosive-
activated valves and start up a DC motor driven pump, driven from
batteries in the same room, that injects a concentrated boric acid solution
into the reactor to shut it down.  If that failed, he'd simply lift
the cover on one of the other three of the quadruply redundant trains
and fire it.  If all of those failed, he'd just sit back and let HPSI
do its thing.  As soon as the pressure drops in the reactor with the recirc
pumps off, steam voiding automatically shuts down the nuclear reaction.
The operator might occasionally trim the pressure control to keep the
cladding below the ignition point but other than that, not much to do.

>and the cladding catches fire

The cladding burned at TMI.  HoHum.  Oh, maybe a few thousand people we
somehow missed died because of this.

>or that a fuel barge tips over on the cooling water intake or  ....

All plants are required to impound enough cooling water inside the compound
to achieve cold shutdown.  Assuming by "fuel" you mean diesel, the fish
might not like it.

>Is the probability of all this equivalent to the probability of a meteor
>strike? If so, what's the evidence?

Well.. Let's see.  Meteors strike the earth every day.  None of your
fantasy has ever happened so one can step out on a limb and say
that the probability of your fantasy is a bit less than a meteor strike.

>>regard?  Why is it that your decisions with respect to transportation
>>(to name one example) are not similarly based primarily on the spectacular?

>We have to make decisions about what we think are credible scenarios and
>what we think are worthwhile risks.

In the venerable words of Tonto, "What's this WE shit, white man?"

[The rest of Yackadamn's interminable anal discharge mercifully deleted]

Yack, you've again ventured out of your normal demagoguery and have tried
to act like you know something about nuclear power.  As usual you failed
miserably.  Maybe you ought to stick to safe areas like telling us how
you quake in the night from your fear of nuclear power.


From: John De Armond
Subject: Re: Yack's daemons (was Re: Nuke Stupidity Rebuttal)
Message-ID: <w++pn!>
Date: 29 Sep 92 06:06:52 GMT (victor yodaiken) writes:

>Your point is nonsense, despite the
>long words you seem so proud of. Anyone wanting technical information
>on this issue could consult the record of the NRC hearings which closed
>Yankee Rowe precisely because of concerns about loss of ductility.

I performance-tested the coolant heating system at TMI-1 and my employees
did the same at several other plants.  But what do I know?

Now yack, I know that being there and doing things does not in your book
qualify one next to words printed on paper but maybe, just maybe this time
you'll listen.  NOT!

BTW, Yankee Rowe was closed because it was deemed not economically
practical to bring the plant up to current standards.  Since it is a tiny
plant and a very old one, this makes sense.  Should be an interesting
decommissioning experience to watch.


From: John De Armond
Subject: Re: Nuclear Power and Climate Change
Message-ID: <>
Date: Thu, 07 Jan 93 06:44:45 GMT (William Carroll) writes:

>I do not know how USAF "hurricane-proof" specs compare with NRC "hurricane-
>proof" specs, but I doubt they vary by a factor of two or three. I'll
>repeat what I said: FPL was very lucky to escape Andrew with as little
>damage to Turkey point as they sustained.

Visit a plant sometime and observe the construction and you will understand
just how "lucky" TP was.  Not meaning to sound smart-assed with that
suggestion, simply suggesting a fact-finding trip.

I don't know what the USAF does but for nuclear power plants, its design
must be able to withstand a wide variety of design-basis insults.
These include the effects of the worst 100-years flood, earthquake,
tornado, hurricane and anything else deemed credible.  Not only
must all safety related structures withstand the wind forces, it
must also withstand wind-propelled missile impact.  The worst threat
is generally considered to be a telephone pole propelled at maximum
wind velocity.  The telephone pole turns out to be the worst in terms
of objects likely to withstand being accelerated by the wind, in
terms of ballistic coefficient, and in terms of its penetrative ability
on impact.

The end result of all this is walls constructed of several feet of
concrete.  At Sequoyah, for example, the aux building (where all
ex-containment safety related equipment resides) walls are 6 feet
thick, the diesel generator building walls are 6 feet thick and
the containment is constructed of several walls of concrete and steel
and inside that is is the many-feet-thick (~20) missile shield that
protects the primary system and instrumentation.

Bottom line, the reason the TP plant, anthromorphicly speaking, yawned
at the hurricane was not luck but design.  There WAS an environmental
incident at TP during the hurricane.  About 10,000 gallons of fuel
oil was spilled from a non-safety-related storage tank.


From: John De Armond
Subject: Re: Nuclear Power and Climate Change
Message-ID: <>
Date: Fri, 08 Jan 93 09:28:52 GMT (William Carroll) writes:

>Suppose the damaged stack had gone over in the wind, with some pieces
>falling on one of the containment buildings, knocking some concrete off,
>but only some chunks a foot or two deep. No breaching of the containment,
>and no real danger of it either.

>The news reports would say "Containment vessel at Turkey Point damaged",
>the layman would think that means breached, the Greenpeacers (who have
>a good presence here) would pitch their tents at the plant entrance and
>the plant would be years, if ever, before splitting atoms again.

While I don't disagree with the predicted media and political reactions,
at some point in time, someone's going to have to say "f*ck the lay
opinions when making these decisions."  The health equivalent would
be to ban blood donations because of some small segment of the population's
irrational fear that AIDS can be caught during donations.  It, like
fear of nuclear power, is thoroughly irrational and not based on fact
but it won't go away.  Even if one does not want to say f*ck it,
the problem still remains of how to pick what irrationality will pop
up next.

As far as a falling brick causing damage, remember the containment is
designed to withstand everything from an airliner crash on down.
When the terrorists fired anti-tank missiles into the
French Super Phoenix, the explosions only chipped out a couple of inches
of concrete.   The brick is not very aerodynamic and thus its terminal
velocity - if it could be achieved in the distance involved - would be
fairly low.

The concrete used in containment and other safety
structures is fairly special and not like anything you're liable to run
into elsewhere.  TVA pioneered a process for using fly ash as an additive
to increase the strength and make it resilliant.  I believe this process
was used for most NP construction.  At Sequoyah, during the interminable
rip-outs-and-redos in an attempt to chase the ever-moving NRC regs,
I watched workers trying to break out this concrete.  Jackhammer
bits would bury up in it without causing cracking.  When hit with a
hammer, the blow was highly damped with no bounce.  Amazing stuff.


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