In the wake of Pacific Gas & Electric's bankruptcy
due to the devastating wildfires, death, and destruction caused by its aging
and vulnerable transmission lines, the big question is, how safe and secure is its
"grid tied" Diablo Canyon nuclear power plant?
Diablo is dependent upon the electric grid to function. Without
electricity, the operator would lose instrumentation leading to the inability
to cool both reactor cores. Unfortunately, out-of-control forest fires and
damaged power lines could cause a "station blackout" in which all
off-site power is lost.
Every nuclear power plant has emergency diesel generators to counter
off-site power loss. Now, especially because of President Trump's threat to cut
back on inspections at atomic power plants, including the Diablo Canyon Power Plant,
my main concerns are whether Diablo's emergency generators are in good working
order and will there be enough on-site diesel fuel to power the facility if the
regional electric grid goes down for a couple of weeks or longer? In the event
of a station blackout, core damage is estimated to begin in approximately one
hour if the auxiliary feed-water system and high pressure injection flow aren't
reestablished in time.
The loss of off-site power could also cause a failure of the spent-fuel-rod
cooling systems. When the spent-fuel cooling pumps stop working, the water in
the pools starts to boil off. Once the Diablo Canyon nuclear power plant's overcrowded
spent-fuel assemblies become uncovered, the fuel rods cladding will start to
melt. As bits of the melting fuel fall into what's left of the water, the water
will flash to steam causing the pressure in the buildings to increase.
Radioactive particles carried in the steam would then begin to exit the
buildings through non-sealed portals and doors.
Exposing hot zirconium fuel-rod cladding to the air causes an exothermic
reaction; the cladding will actually catch fire at about 1,000 degrees centigrade
causing toxic radioactive isotopes to be released into the atmosphere. Even the
Nuclear Regulatory Commission concedes that this type of fire cannot be
extinguished.
Another reason why PG&E is caught between a rock and a hard place is
because of its mandatory power cut-offs during hot, dry, and windy weather.
Will Pacific Gas & Electric have to choose between power outages to curb
the possibility of raging wildfires and the threat of a "station blackout"
at its more-than-hazardous Diablo Canyon nuclear power plant? What if a major
Fukushima-like-earthquake were to occur during a "station blackout" during
which all off-site electricity is lost due to a mandatory power cut-off? This
definitely is a lose-lose situation! Why must we continue to live with
this unnecessary danger?
Now more that ever, it's time to Close Diablo Down!