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PG&E control-room operator: 'We're screwed'
San Francisco Chronicle ^ | 3/8/11 | Eric Nalder, Chronicle Staff Writer

Posted on 03/08/2011 10:28:51 AM PST by SmithL

A "screwed-up" repair project at a Pacific Gas and Electric Co. control station in Milpitas caused pressure levels to rise on all the natural gas transmission lines serving the Peninsula just 50 minutes before the San Bruno pipeline exploded, newly released federal documents show.

The repair project set in motion a chain of unforeseen problems and blunders leading up to the Sept. 9 explosion that killed eight people and destroyed 38 homes, records released by the National Transportation Safety Board show.

Electricity was cut off to equipment that controls gas pressure in the Peninsula pipelines, two backup power supplies failed to work and critical communications between PG&E's gas control center in San Francisco and the Milpitas control station were lost, the records show.

When the power was cut to the control station in Milpitas, a system set up by PG&E automatically increased pressure on all three Peninsula pipelines, including the one coursing through San Bruno, according to PG&E employees interviewed by the safety board. The federal agency is investigating what caused the explosion.

Through it all, operators in the San Francisco control room proved powerless to fix the problem.

"We're screwed, we're screwed," one operator said minutes before the 30-inch gas transmission line exploded.

(Excerpt) Read more at sfgate.com ...


TOPICS: Business/Economy; Extended News; US: California
KEYWORDS: pgande; pipelineexplosion; sanbruno
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The San Bruno pipeline explosion and fire in September killed eight people and destroyed 38 homes.
1 posted on 03/08/2011 10:28:58 AM PST by SmithL
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To: RhoTheta

Ping.


2 posted on 03/08/2011 10:36:56 AM PST by Egon (The difference between Theory and Practice: In Theory, there is no difference.)
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To: Egon

How did this happen under all the California Regulations.


3 posted on 03/08/2011 10:40:52 AM PST by scooby321
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To: SmithL

Time to fire some people and for them to financially pay for it to those who were affected.


4 posted on 03/08/2011 10:42:12 AM PST by archivist007
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To: scooby321
How did this happen under all the California Regulations.

Affirmative Action?

5 posted on 03/08/2011 10:43:17 AM PST by dfwgator
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To: dfwgator

Union affirmative action.


6 posted on 03/08/2011 10:44:41 AM PST by Parley Baer
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To: SmithL

Umm, just a naive question.

Why aren’t there safety precautions in place that can prevent this from happening?

I’ve designed Hydraulic testers for a living, every one of them had EMERGENCY precautions to prevent this sort of thing from happening, yet these testers dealt with very high pressures and flow rates. Yes, if left without safety bypass valves - this was a very dangerous piece of equipment.

There is an Operational Range of pressure - then there is the HOLY S**T range where automatic safeguards SHOULD have kicked in, shut down the pumps, and bled off the pressure before something like this happened.

What happened to very basic safety design reviews?


7 posted on 03/08/2011 10:44:48 AM PST by Hodar (Who needs laws .... when this "feels" so right?)
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To: SmithL
a system set up by PG&E automatically increased pressure on all three Peninsula pipelines

An interesting fail-safe response.

Now the media often screws up this kind of reporting but will be interesting to see follow up info.

8 posted on 03/08/2011 10:45:15 AM PST by nascarnation
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To: SmithL

Another instance of the Pepsi Syndrome?


9 posted on 03/08/2011 10:47:04 AM PST by A. Patriot (CZ 52's ROCK)
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To: scooby321

Looks like they need mooooore regulation /s


10 posted on 03/08/2011 10:48:51 AM PST by MaxMax
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To: Hodar
I’ve designed Hydraulic testers for a living, every one of them had EMERGENCY precautions to prevent this sort of thing from happening, yet these testers dealt with very high pressures and flow rates. Yes, if left without safety bypass valves - this was a very dangerous piece of equipment.

I think this will be blamed as the precipitating reason for the failure, however I believe the line was already damaged from previous sewer line "burst" construction upgrades. From experience I believe this line would have failed anyways, but could not predict the severity. It may have started out with a slower detectible leak.
11 posted on 03/08/2011 10:52:09 AM PST by PA Engineer (Liberate America from the occupation media. There are Wars and Rumors of War.)
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To: dfwgator

Nepotism is RAMPANT there. You know.


12 posted on 03/08/2011 10:52:09 AM PST by SMARTY (Conforming to non-conformity is conforming just the same.)
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To: Hodar

This is what happens when a repair crew isolates the pressure gauges to the regulators, which thinks the pressure is dropping when in fact it is increasing. Bad data = bad results.


13 posted on 03/08/2011 10:54:08 AM PST by BipolarBob (I'm BiPolar,BiWinning AND have a clean drug test. Questions? Call 1-800-CharlieSheen)
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To: A. Patriot
Another instance of the Pepsi Syndrome?

But, you spilled a Coke.

14 posted on 03/08/2011 10:57:26 AM PST by dfwgator
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To: Hodar

Why no failsafe built into the system? If electrical power is a critical component, the absense of it should trigger a failsafe to avoid such a catastrophe.

Or am I missing something?


15 posted on 03/08/2011 11:02:43 AM PST by AFreeBird
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To: scooby321

Union workers, probably on break.


16 posted on 03/08/2011 11:03:38 AM PST by org.whodat
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To: SmithL

I work for a company that does control systems for these type of operations and this is inexusable. There should have been multiple fail-safes and some method of shutting down the lines in such an emergency. It also appears a pressure sensor or sensors were reading wrong. I’d love to know who manufactured that sensor.


17 posted on 03/08/2011 11:05:55 AM PST by Peter from Rutland
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To: AFreeBird

I agree, every safety device I have used was fully automatic. Never used a computer to respond to an emergency (computers can lock-up), never made a signal’s absense allow flow (wires get cut).

The default condition was zero flow. Things had to be perfect before flow was allowed - any failure shut the system down. The simple trick, is to make the safety system easy enough to understand, quick enough to matter, and robust enough to withstand an emergency.


18 posted on 03/08/2011 11:07:18 AM PST by Hodar (Who needs laws .... when this "feels" so right?)
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To: _Jim

ping


19 posted on 03/08/2011 11:08:16 AM PST by null and void (We are now in day 776 of our national holiday from reality. - tic. tic. tic. It's almost 3 AM)
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To: AFreeBird
Why no failsafe built into the system?
All systmes are subject to failure. When a fail safe system fails, it fails by failing to fail safely.
20 posted on 03/08/2011 11:49:02 AM PST by dblshot (Insanity - electing the same people over and over and expecting different results.)
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