Hmmm. I thought most buildings already had that -- at least for basic
systems like exit and power-failure lights. One of the lessons learned in
the first Wold Trade Center bombing was that a central emergency system
generator, if destroyed -- which it was, can't do any good when the power
failures. The WTC replaced stairway lights with local battery-power units
which did work on 9/11.
I see battery-powered egress lights in restaurants, churches, stores, etc.
now. Something for elevators sounds a bit more expensive especially for
tall buildings, but even a system that returns the elevator cab to the main
floor could be powered by something like a car battery for the bit of power
and limited time required.
There was an a outage, the cause of which is still undetermined.
"Two nuclear reactors at Florida Power & Light's Turkey Point station in
South Florida shut down Tuesday afternoon, the Nuclear Regulatory
It is unclear if the loss of power caused the outage or if the outage
caused the reactors to trip. "Turkey Point temporarily lost off-site
power, and both reactors tripped," said NRC spokesman Roger Hannah.
The cause of the outages remains unclear, Tampa Electric spokeswoman
Laura Duda told the newspaper.
She described a "significant disturbance" on the state's electric grid.
It could have been a transmission problem, or a large electricity
generating unit unexpectedly going off line, or another problem
altogether. "We are working with other utilities to figure out what the
problem was," she said."
Whatever it was, it was purely operational, not safety-related.
A switch failed causing a huge "ripple" in the grid, which in turn
caused the nuke plants to react defensively by shutting down to avoid
being overstressed by the sudden imbalance. IOW, they shut down for
Probably ought to clarify that a bit--the LOCA (loss of coolant
accident) part wasn't actually an operator error; it occurred when the
PORVs (pilot-operated relief valves) did not automatically reseat after
The problem occurred on the operator response to the incident wherein
they interceded w/ the HPI (High pressure injection) systems and later
the RCPs (reactor coolant pumps) on the basis of their misinterpretation
of the pressurizer level instrumentation indication and the fact they
did not recognize they had a leak (stuck PORV).
This came about because the PORV location was close enough to the
pressurizer outlet that the liquid-water interface became comingled
owing to the flow disturbance. This confused the level indication which
was a dP cell across the interface.
Consequently, they erroneously concluded that somehow they were in
danger of filling the pressurizer solid w/ water which is a no-no, hence
they turned off the HPI to avoid (they thought) doing that. Then, after
a while as they continued to lose cooling water, the RCPs began to
cavitate and they were turned off to prevent damage to them. At that
point they then had a core becoming uncovered and no longer had forced
circulation of what coolant they did have and things went downhill from
As I noted previously, the shift which came on next recognized the
symptoms when they were going through the shift turnover meetings and
began recovery operations immediately.
As a very brief synopsis, this leaves out a lot of detail, of course,
but is a general description of what went wrong at TMI. There are a
couple of obvious things here, the most obvious of which was the
question of how, if the system were in danger of going solid, could
there have been such low coolant level as to have caused RCP cavitation?
What went right, of course, was that HPI was incorporated in the system
and once it was restarted to cover the core and the RCPS were again on
to circulate flow, the accident was on its way towards mitigation.
Of course, the sad part is that if the operators had simply left the
system alone, there would have been nothing but an operational incident
of the stuck PORV (for which there was already a pending corrective
action/notice in place) and after a short outage to repair/correct it,
the plant would have been back in operation.
TMI-2 was virtually a non-accident: A small volume of irradiated steam was
released to the atmosphere. There was no injury to any thing or any one.
It's all about timing, folks...
March 16, 1979 - The China Syndrome starring Hanoi Jane
and Jack Lemmon opens in theaters.
March 28, 1979 - Three Mile Island Unit 2 incident
April 26, 1986 - Chernobyl #4 disaster
"Slightly" different containment philosophy, too. U.S. reactors are housed in
containment structures consisting of 3-4-foot-thick, steel reinforced concrete
able to withstand the direct impact of a Boeing 727.
The Soviet Union's idea of containment at Chernobyl (and others to this day)
is the equivalent of a metal-sided pole shed.
TMI-2 "belched" some bad steam.
Chernobyl-4 exploded, melted-down and killed virtually everyone that worked on
the subsequent job of encasing the core in concrete. The direct fallout
"nuked" a nearby, evacuated city. It is still abandoned but barely "hot".
*Normal* wildlife and flora flourish there and have for years.
Kudos to George W. Bush to be the first President since the 1970s to have the
guts to actually call for more nukes. We can (and should) build more nuke
could of been much worse if cooling hadnt been restored..... there was
concern of a explosion in the containment too
not strong enough for larger planes espically with a full load of fuel
in use today and they have been used as weapons:(
yeah like the spent fuel storage rods in cooling pools nationwide.
perfect terrorists targets........
have you looked at the zone of exclusion, far more than one city its a
entire region where humans cant safely live for probably a thousand
theres lots of wildlife, but those animals suffer from tumors cancer
and early death. true humans arent around to bother them. animals move
into the thousands of abandoned but still standing buildings
Well good old bush isnt exactly known for being a intelligent
president, his legacy is one of failure. his approval rate under 30%
the vast majority dont trust his judgement
for the pro nuke plant people...........
long term can you guarantee safe storage of spent fuel till its
how about short term storage in pools near reactors?
imagine a plane laden with explosives being flown into a storage pool.
how would the nuke power industry pay for long term thousand year
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