×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

San Bruno 30" Natural Gas Transmission Line, -FAIL-
10

San Bruno 30" Natural Gas Transmission Line, -FAIL-

San Bruno 30" Natural Gas Transmission Line, -FAIL-

(OP)
This is just a notice to the folks who haven't heard about the recent pipeline disaster in San Bruno California.  The San Francisco airport is in the small town of San Bruno.

http://www.cnn.com/2010/US/09/10/california.utility/index.html?eref=rss_latest&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2Fcnn_latest+%28RSS%3A+Most+Recent%29

http://www.mercurynews.com/ci_16051111?nclick_check=1

Keith Cress
kcress - http://www.flaminsystems.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

There is extensive coverage in the San Francisco Chronicle website SFgate.com

It is now thought by some that the fault was caused, possibly, by sewer replacement work in 2008 which may have damaged the 30 inch HP gas transmission line at the corner of Glenview and Earl Streets in San Bruno. The sewer work had to pass under the gas line. Some commentators have posted a google street view that clearly shows asphalt patches near the gas line. Residents had complained of gas oders for weeks previously, but no action was apparently taken.

The gas line was built in 1948, some say 1956, at that time possibly in open country before the subdivision was developed.

This raises questions as to why it was allowed to build houses only a few tens of feet away from the line.

One view is that the gas leakage was into the sewer main which had to be only vented via house vents, manholes would have had new sealed covers to avoid I and I as this was not a combined sewer (no stormwater). My opinion only.

Another commentator mentioned that the pipe was blown out of the ground, indicating an explosion from below. 40 feet of pipe were ejected, the fire crater was 167 feet long, per one report.

rasevskii
 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

(OP)
I have problems with the, "reports of gas odor and nothing was done".   PGE immediately checks any and all reports of leaking gas and I would expect major attention when it's reported around a transmission line that is ranked as one of their most dangerous.

Time will tell I suppose.

Keith Cress
kcress - http://www.flaminsystems.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

2
From the wall St Journal:

"SAN BRUNO, Calif.—The ruptured natural-gas pipeline that exploded and destroyed 58 homes in the San Francisco suburb of San Bruno contained a longitudinal seam and numerous welds indicating it had been made from many small segments of steel pipe—an unusual configuration—federal investigators said Saturday"

http://online.wsj.com/article/SB10001424052748704644404575482634243573338.html?mod=WSJ_hpp_MIDDLENexttoWhatsNewsThird

I bet that there was damage done the this 40-50 year old line and an inadequate repair during the sewer work.

You know how organizations work.......ummmm....PG&E was very busy at that time......we meant to go review the low-bid contractor's work....they filled in the hole before our inspectors got there......they ran out of approved weld rod....so they used coat-hanger wire.

I can see the MBAs making excuses now......

What I truly want to know is this:

In the USA, how many other 50 year old high pressure mains run through neighborhoods with families, women and children ?

To what standard and HOW OFTEN ARE THESE MAINS INSECTED ?

DON'T THE PEOPLE WHO LIVE ABOVE THESE MAINS HAVE A RIGHT TO KNOW ABOUT THE DEADLY THREAT UNDER THIER PROPERTY ?

ANYBODY ?????????????????????????????????????????

-MJC

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Well, it seems that the sewer replacemrent was done by trenchless technology involving pipe bursting of the old sewer line. Old diameter 6 inch, new PVC liner 10 inch. Unlikely that the old line in Earl Street was only 6 inch dia. Distance between sewer and HP gas line...? Was anything inspected...

Should be interesting...

rasevskii

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

2
MJC,

i find it difficult to believe that an operating would casually treat/dismiss or otherwise a "known" or needed repair on a HP gas transmission P/L in a HCA.  if so, then hopefully the responsible people are prosecuted to the fullest extent possible.

"In the USA, how many other 50 year old high pressure mains run through neighborhoods with families, women and children ?"
There are many and they are required to be inspected IAW PHMSA 192.
(http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr;rgn=div5;view=text;node=49%3A3.1.1.1.4;idno=49;sid=2a78ba43e64defb9760c86d446d934ba;cc=ecfr#49:3.1.1.1.4.4.9.16)

I know of several installed before WWII and these pipelines are still in operation.

"To what standard and HOW OFTEN ARE THESE MAINS INSECTED ?"
see previous answer . . . + ASME B31.8 & other associated stds.

"DON'T THE PEOPLE WHO LIVE ABOVE THESE MAINS HAVE A RIGHT TO KNOW ABOUT THE DEADLY THREAT UNDER THIER PROPERTY ?"

you need to understand that many pipelines were built long before the population swelled to current levels; thus, development in areas close to pipeline ROWs.  so, when people build near pipelines (transmission or otherwise), there right to know is dependent upon the survey data they obtained before they purchase of property.  Also, when people/organizations plan to develop near p/l's then the operating company is most likely well-informed either by notification or when aerial patrols are conducted.

hope this helps.
-pmover

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Third party damage is responsible for about 75% of all pipeline ruptures.

Inspection is required by Federal Law for Interstate Pipelines - those Covered by CFR 49 Part 192.

Inspection is also required for intrastate pipelines by all state laws that I've read (but I haven't read all of them).

Gathering system pipelines, except in federal offshore areas, are seldom regulated at all.

          Maximum Interval between Patrols
Patrol Frequency for Natural Gas Transmission Pipelines

Characteristics of Area Consisting of  220 yards of 1-mile Length of Pipeline described by Cat I, II, III

(Cat I) Any location having fewer than 46 buildings intended for human occupancy

At Highway and RR Crossings    At All Other Places
 7.5 months; but at least        15 months; but at least
 2 each calendar year.           1 each calendar year.

(Cat II) Any location having 46 or more buildings intended for human occupancy or where the pipeline lies within 100 yards of a building

At Highway and RR Crossings    At All Other Places
 4.5 months; but at least        7.5 months; but at least
 4 times each calendar year.     2 each calendar year.

(Cat III) Any location where buildings with four or more stories above ground are prevalent

At Highway and RR Crossings    At All Other Places
 4.5 months; but at least       4.5 months; but at least
 4 times each calendar year.    4 times each calendar year.

The problem with those regulations is that the method consists of patrol and visual site inspection and does not attempt to evaluate the pipe, which will be buried underground 99.999% of the time.

If the patrol misses any construction activity being conducted along the RoW, there of course can be high potential for damage.  Future inspections should take careful note of any patches, dead bushes, deep marks or gouges in surrounding curbs, etc. and a further more detailed investigation undertaken, but I believe that such measures are seldom sufficient, if accomplished at all.

Pipelines are required to upgrade the area class and make alterations to the pipe design when any area classes change, but there can be a significant number of changes needed to finally jump class, so that can leave gaps in the safety level required in the prevalent area class verses what might be actually happening within some part of the area.  I.e. should safety requirements really be any less of a concern, if there happened to be 45 houses in the area rather than 46.  Or possibly even 1 house, if it happened to be your house?


 

"I am sure it can be done. I've seen it on the internet."  BigInch's favorite client.

"Being GREEN isn't easy." Kermitfrog http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

When buying a house the survey would show easements and property might have deed restrictions related to a pipeline on that lot.  Pipeline markers are normally located at streets and periodically along the line.  Still it is possible that some of the general public would be unaware of a pipeline in their neighborhood.

I have a crude pipeline in the back yard of my 31 year-old home; closer to 6 NPS than 30 high pressure gas.  I don't know if the crude line is in operation or not.

Perhaps rather than operating, it seams reasonable to replace a 30-inch high pressure gas pipeline that is over 50-years old.  However I bet that replacement would entail lots of legal action.  Regardless expect to hear plenty about this over the next few years.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

JLSeagull:

Hardly anyone in a neighborhood would know the existence of a pipeline, except an engineer who had interest in such things. Not likely any Real Estate agent would tell a prospective buyer or that he would even know himself.

The current other big pipeline accident of a 34 inch crude pipeline at Romeoville. Ill, runs right down the street of an industrial park, and appears to run under streets of an adjacent suburbia. Google "Enbridge Pipeline Accident" or similar. There is a pdf with a map. Search Enridge_pipeline_map.pdf (the name is spelled wrong actually)

How are pipelines marked under paved streets, what do the markers look like?

rasevskii

 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

JLSeagull et al,

pipelines regulated by PHMSA 192 are required to have pipeline markers identifying pipeline installations.

from:http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr;rgn=div5;view=text;node=49%3A3.1.1.1.4;idno=49;sid=2a78ba43e64defb9760c86d446d934ba;cc=ecfr#49:3.1.1.1.4.4.9.16

§ 192.707   Line markers for mains and transmission lines.

(a) Buried pipelines. Except as provided in paragraph (b) of this section, a line marker must be placed and maintained as close as practical over each buried main and transmission line:

(1) At each crossing of a public road and railroad; and

(2) Wherever necessary to identify the location of the transmission line or main to reduce the possibility of damage or interference.

(b) Exceptions for buried pipelines. Line markers are not required for the following pipelines:

(1) Mains and transmission lines located offshore, or at crossings of or under waterways and other bodies of water.

(2) Mains in Class 3 or Class 4 locations where a damage prevention program is in effect under §192.614.

(3) Transmission lines in Class 3 or 4 locations until March 20, 1996.

(4) Transmission lines in Class 3 or 4 locations where placement of a line marker is impractical.

(c) Pipelines aboveground. Line markers must be placed and maintained along each section of a main and transmission line that is located aboveground in an area accessible to the public.

(d) Marker warning. The following must be written legibly on a background of sharply contrasting color on each line marker:

(1) The word "Warning," "Caution," or "Danger" followed by the words "Gas (or name of gas transported) Pipeline" all of which, except for markers in heavily developed urban areas, must be in letters at least 1 inch (25 millimeters) high with1/4inch (6.4 millimeters) stroke.

(2) The name of the operator and the telephone number (including area code) where the operator can be reached at all times.

while the requirement is "vauge" insofar as distance between markers, the operating company will need to exercise "due judgement".  for example, a pipeline across the desert SW USA (Class 1 location) with no dwellings or nearby roads will likely not have any pipeline markers.  however, the ROW "may" be cleared and maintained allowing good visual observation.  in class 2, 3, or 4 locations, pipeline markers are placed per the regulations; however, "some" operating companies place more pipeline markers so as to be visually observable from other p/l markers.

MJC,
i do not believe that p/l operators install 5d bends in pipe that large.  they "may" have done so back when the pipeline was installed, but not these days (3D or smaller for pipe that size) simply because of the pigging requirements/operations.

believe me, the PHMSA/PGT investigators will investigate the cause, conduct further research, and institute more regulations . . .

yes, when HP pipeline rupture, it creates one heckuva roman candle, but there is ample energy sitting in the fuel tank of the vehicle you drive too.

hope this helps.
-pmover

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

They should make land developers pay for the pipeline relocation if they want to develop over existing pipelines... It amazes me they let this happen, and still today, residential developments are being constructed over high pressure gas, oil, and products transmission lines. I have investigted failures at a couple of these similar scenarios...

I often target pup or tie-in locations for SCC digs (not saying this failure has anything to do with SCC). These are higher areas of residual stress which do not help matters, especially if there is 5 in row. If you have ever seen some construction crews "fit" these in, especially in 1950's era.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

So that begs the question: Was the San Bruno pipeline actually marked? It was under a paved  street (Glenview Drive) Do the markings still exist over the undamaged portion?
Were they removed/paved over when the development was built?
This would be an interesting site survey, for all similar situations...

rasevskii

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

rasevskii et al,

do bear in mind that there are hundreds/thousands of pipeline crossings under paved roadways/surfaces.  my experience has been that a thorough engineering analysis is done for all road crossings to minimize any impact loads onto the pipeline.  some crossings are cased and others are not.

brimmer,
operating companies do generally charge developers for relocating pipelines to meet the needs.  bear in mind that relocating a HP gas transmission pipeline does require engineering analysis as their could be impacts to other facilities.

btw, good to hear of the target areas you mentioned . . . there are others to consider.  yes, construction and inspection crews in the 1950s is certainly different than today's standards.  the objective is to minimize all risks and hazardous situations.

hope this helps.
-pmover

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

(OP)
I'm surprised that a transmission main was only 3ft down.  I'd have guessed 6ft for more protection.   Is 3ft a typical depth of transmission lines?


-------------------
How come they aren't having service problems?  They've lost a 30 inch high pressure line!  Why isn't there a gas shortage somewhere in the region?  What diameter line would one need to supply a large metropolitan area?  Say 4 million people?

Keith Cress
kcress - http://www.flaminsystems.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

it appears to me that the permanent pipeline markers in the street are not required by the standards since there is a damage protection program in place. Underground Service Alert (USA) one call notification is a key part of the damage protection plan and virtually all utility companies participate in the plan. Temporary marking with paint is about all you can expect to see and will only be done when a contractor calls in a request for marking.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

30" depth of cover is the minimum for newly installed lines, but you aren't required to maintain 30" cover.  It could be reduced because of farming, grading, etc.  

I would say that anywhere from 30" - 60" of cover is pretty normal, with a handful of lines being deeper.  

I would imagine that there aren't service interuptions because it isn't winter, so the load isn't at a peak level.  (Assuming that the primary load is residential heating).  They may have curtailed industrial customers.  

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

cvg:

In fact, tracing the San Bruno line northwards, up Glenview Drive, using Google Maps and Street View, there are only USA markings seen in the streets. There are two 90 deg bends, then it passes crosswise under Sneath Lane, through an empty lot, (no house could be built there on top of the pipe) under a basketball court, then through 10 or more back yards (off street) before reaching a valve station in a fenced area....The route is easily seen by an expert...

I hardly imagine many of the homeowners/renters have any idea about this...

Hard to imagine this line ever going back into service in this environment on this routing.

rasevskii

 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Here's your answer to your right to know...

www.npms.phmsa.dot.gov

Locations of underground pipeline or facilities is not a secret the big bad companies are keeping from you.  But no one comes knocking on your door to remind you that there's a pipeline in your backyard, radon in your basement, acid in the rain, or that the sky is going to fall on your little head.  State/Fed Regulations however stiff and ridiculous they may seems do try to, in my opinion, balance both the operating requirements of the company in terms of inspection, monitoring, maintenance, and repair, and overall risk mitigation to the general public.

High pressure gas lines, large and small, run in all sorts of places you would never expect...next to schools, through mall parking lots, in back yards of million dollar homes.

It's an absolute trajedy that this happened in a location such as this.  PG&E should be liable for every dollar those people are out.

I'm don't doubt that the line will go back in service, but it won't be next week and not with out a load of hydro testing or smart pig runs or maybe both.
 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

(OP)
A large damage multiplier was the fact that even with two 30" openings the pipe bled huge volumes for hours.  Because of the active leak fire responders.. don't!  They waited until The Jets were out before they did very much.

Over and over this happens.  Remember CalNev?  A pipe ruptured at the bottom of Cajon Pass and 90 octane gasoline at 2000psi sprayed all over a housing tract.   The safety officer said the most horrid mind altering result for him were the screaming crying people begging him to "shut it off".  It couldn't be shut off.   All they could do was wait until the line drained from Barstow to San Bernardino - about a day.

They now have commanded valves scattered about.

Why not put in valves every hours worth of volume?

Keith Cress
kcress - http://www.flaminsystems.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

More valves would help limit the volumes released after a break up to a point, however the argument in that situation is that each added valve actually increases the likelyhood of leaks to some extent.  Although specific maximum distance limits between valves is mandated by the pipeline codes, during the valve location study, the potential spill volume contained between any two valves is balanced against a risk factor associated with spilling such a volume within the resulting pipeline segment and an optimum distance between valves, often less than the maximum permitted distance, is so obtained.

The danger of such a logical implementation of valve distancing is that the exercise is often limited to being choosen only by a computer program that balanced calculated risk with volume and without any consideration of other factors within the resulting segments.  Valves were placed without regard to what was actually located in the route, without regard to actual hydraulic profiles and leak-driving pressures after the valves were cosed, valves being located without regard to the "gravitational flow" and placed on the downstream side of rivers and population centers where the closed valve would actually direct flow to the most sensitive area within the segment, (gravitational flow actually having reversed the usual flow direction), valves being located at local high points, such as at mountain ridge crossings where a break on either side would not have limited flow at all, valves located at local low points where, if a leak occured just upstream of one of them, the whole volume in the segment would be dumped into an adjoining river, valves sites being located within the flood zone of a nearby river, or even chosen without verifying that there is quick and convenient access to the valve sites.   

"I am sure it can be done. I've seen it on the internet."  BigInch's favorite client.

"Being GREEN isn't easy." Kermitfrog http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

At this point in the discussion, it would be interesting to compare the current regulations for USA gas pipe routing to those in Europe.

Anybody ?

It seems to me that, despite additional inspections and living with a complex piping network, that replacement improvements can be made, especially where residences are concerned or where there is a high probability of death.

Despite a vigorous and well designed inspection programs, at what point in time does it make sense to simplyreplace the underground piping ?

After 30 - 40 - 60 Years ?  Was the piping system meant to last forever ? Many bridges do not last for 50 years.

Yes, of course it will be very expensive....

But everything, sooner or later, wears out or corrodes away.

Also, am I to understand, based on the discussion above, that a 30 inch diameter pipe can have as little as 30 inches of cover ?

What would be the cover requirements in Europe ?

My opinion only...

-MJC

 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Let's keep in mind that the first responders to this incident did not realize that this was a pipe failure. Being rather close to SFO (San Francisco International Airport), they assumed they were responding to a major aircraft incident. Took roughly half an hour to determine that they were dealing with a pipeline problem. I don't think this was so much of a question of deinventorying the pipe as it was of simply getting around to turning the wheel to close the valve.

The NTSB is looking into PG&E's slow response in cutting off the source: National Transportation Safety Board vice chairman Christopher Hart said Tuesday that constructing a timeline of how PG&E crews based at a pipeline-monitoring terminal reacted to the blast would be important to determining why it took the utility two hours and 46 minutes to cut the gas that fueled Thursday's devastating blaze.

Let's all keep in mind that virtually everything at this point of the investigation is somewhere between outright speculation and eyewitness accounts. The investigation will take time to complete - I'd expect to get some preliminary reports from the investigators in 30-60 days and final reports will take about a year.

jt

 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Just because a pipeline is X years old doesn't mean that it is in good or bad condition.  There are lines that are 80+ years old that are still in service with no problem, and there are also lines that haven't lasted 10-20 years before failing completely.  I'm not sure that mandatory replacement at some arbitrary age will make pipelines any safer.  

Natural gas pipelines are obviously used to supply fuel to people, so they need to go where people are.  Since many of these lines were constructed years ago, there wasn't much there when they were built.  It is amazing how land developers will try to crowd pipelines in order to get a little more developable land.  

 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

MJC,

Cover requirements in most places would be 36", but yes you are correct, it can be reduced to 30" when the trench is excavated in hard rock.  Outside the USA, 1 meter (39.4") cover is commonly used, sometimes reduced when extra protection is provided as a compensation for the clearance reduction.

During the last few years it became mandatory in the USA to build in the capability to run instrumented pigs for periodic internal spections.  The wall thickness remaining, localized corrosion and other irregularities captured during such inspections are used to determine the repair and/or retirement schedules, rehydrotest, or operating pressure reductions that might be needed to keep the risk down and safety levels high... if everything were to work like it should.

2 hours to stop a gas pipeline leak and fire would be a fine achievement by most standards.  Some large diameter, high pressure pipelines with valves at maximum spacing requirements can burn for 24 hours or more until they finally run out of gas and flame out.  For a significant rupture it is quite unusual to be able to put them out by any means before the gas is totally consumed by flame.  In fact, its quite difficult to get near enough to them just to spit and run.  

There was some guy just a month ago that was asking for advice on how to build some kind of garage over a gas pipeline RoW on his property.  We red-flagged it as one of those things that simply should not be discussed in these forums and the thread was removed.  No point promoting those kind of ideas in any manner, even by just giving them "press coverage".   The internet has proven that 1 idiot + 1 idiot can equal millions.

"I am sure it can be done. I've seen it on the internet."  BigInch's favorite client.

"Being GREEN isn't easy." Kermitfrog http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

I lived in the same subdivision in two different houses for 31 years.  In the first house part of the rear of my property was a ROW for a 30" and a 24" NG pipeline.  If you burned gas in the Cleveland, OH area, it probably passed through my property on its way to you.  I later moved to another residence, and the pipeline ROW was immediately across the street from my front yard.  My bedroom window was ~60 ft from the ROW.

A piece of one of the lines blew out of the ground in a low swampy spot about 2 miles away and something like 21 ft of 30" pipe landed more than several hundred yards away, so it wasn't like it couldn't happen here.

I only worried about those lines in the low boggy or swampy points.

To the subject of the pipeline companies paying attention, once I had some dirt hauled and borrowed a tractor with a back hoe to move it around.  I had the tractor parked on the ROW (this was at the residence where the ROW was in my back yard) and within hours a pickup truck drives onto my property and the district Sup't introduces himself.  When he was satisfied that my intentions were not to dig on the pipeline, just to push some dirt around away from the ROW, he left, but not until.

I was impressed at how soon after I parked the tractor that he showed up and it was a Sunday afternoon too.  They regularly had an airplane fly the line and look for and report problems and things like earth moving equipment parked on the line.  If you knew what to listen for you could hear or see them with regularity.

His visit gave me a real comfort with respect to living next door to that next door neighbor.

For me personally, heck, I was constantly in and out of Nuclear power plants, super critical power plants, paper mill chemical recovery boilers, chemical plants that made lethal stuff, (Phosgene the one I can remember).  And, I had to drive the public highways to get to and from them.  I always figured that if the Good Lord wanted me home, He had plenty of ways to take me.  Frankly, I didn't worry much about the pipeline.

rmw

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

(OP)

Quote (jte):

The NTSB is looking into PG&E's slow response in cutting off the source: National Transportation Safety Board vice chairman Christopher Hart said Tuesday that constructing a timeline of how PG&E crews based at a pipeline-monitoring terminal reacted to the blast would be important to determining why it took the utility two hours and 46 minutes to cut the gas that fueled Thursday's devastating blaze.

Wow.  That is ridiculous.  How could the operators 20 miles away, as the crow flies, not have noticed 40 feet of a 30" line missing?!  I can hardly wait to read the report on that.

Shades of that Siberian train-in-canyon disaster.  "Pressures dropping Igor, adjust it back up."

Keith Cress
kcress - http://www.flaminsystems.com

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

pmover, et al..

I think that the most important bit of information in the preliminary investigation is:

"Investigators found that while the longitudinal seams on some of the pipe segments were fusion-welded from both inside and outside the pipe, some were fusion-welded only from the outside of the pipe. In order to understand this variance, investigators are in the process of researching pipe welding standards and practices in effect at the time the pipeline was installed in 1956."

My Translation:

"... the piping met the (logitudinal seam-welded) quality standards of that time (54 years ago) BUT if we were to produce such pipe now, we would be a lot more careful"

I stand by my intuition:

Old piping standards + 54 years + unknown pressure surges + California real estate market + marginal cover = disaster

Nothing lasts forever,

-MJC


 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

As I understand it, longitudinal seam welded pipe made before 1970 is a well kown problem.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

In a recent past life, I drove daily within 10 ft of a NG pipeline valving and/or metering station so old that it has riveted pipe.  And it is still going....

Too bad I live 300 miles away now or I'd post a photo.

rmw

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Actually, it's probably a good thing you live 300 miles away.   

Mike McCann
MMC Engineering
Motto:  KISS
Motivation:  Don't ask

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

I don't believe you saw riveted pipe, but maybe a separator/filter since riveted pipe use was stopped at the turn of the 20th century.  

BUT, from a the sprial weld pipe company,there is some possibility read this


"The first recorded installation of steel pipe with riveted seams occurred in Railroad Flat, California, in 1858. Records show that some installations of steel pipe in San Francisco laid in 1863 are still in use today. Large diameter riveted steel pipes supplied the needs of our growing nation for more than 50 years. The labor intensive assembly of riveted pipe seams and joints were replaced by the development of the lock seam method in 1905. In the early 1900s electric welding processes were being developed
and, by 1932, replaced the lock seam joining method for forming steel pipe."

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

I would like to know the original design operating specifications for the pipe. Pressure, flow rates and design factor(safety factors). I suspect orginally this pipeline was designed for lower specifications and at some later date there was approval to utilize this pipeline at higher pressure and flow rates. The higher specifications would probably not be a great concern however the higher specifications allowed higher flucuations in pressures during normal operations causing additional fatigue problems in the welds. I suspect the final cause will be metal fatigue in the weld joint or in the heat affected zone in the parent material.  

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

dcasto,

You may be right about that.  It may well have been a vessel in the pipe manifold although the gas field common to the area dated back to the turn of the last century.  I have seen and been around several riveted drum boilers dating from earlier last century, so I didn't think too much about it either way other than to note that it was older than dirt as indicated by its being of riveted construction.

rmw

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Here is an update from NTSB, did not see it in posts above.

NTSB ISSUES UPDATE ON INVESTIGATION INTO FATAL PIPELINE
RUPTURE IN SAN BRUNO, CALIFORNIA
************************************************************
This is an update on the continuing investigation of the
natural gas pipeline rupture and explosion that killed eight people in San Bruno, Calif., on September 9, 2010.
The investigative group conducting the metallurgical
examination of the pipe is chaired by the National
Transportation Safety Board and includes technical experts
from the Pipeline and Hazardous Materials Safety
Administration (PHMSA), the California Public Utilities
Commission (CPUC), and Pacific Gas & Electric (PG&E). This
group is in the midst of an exhaustive evaluation of the
ruptured pipe pieces. What follows is factual information
that has been developed at this early point in the
investigation.
PG&E survey sheets and charts for the rupture location
indicate that the pipeline was constructed of 30-inch-
diameter seamless steel pipe (API5L Grade X42) with a 0.375-inch thick wall. Evidence obtained so far, however,
indicates the pipeline in the area of the rupture was
constructed, at least in part, with seam-welded pipe.
After the ruptured pipe surfaces were thoroughly surveyed,
all of the asphalt coating was removed and the pipe was
cleaned to allow for visual inspection and nondestructive
testing (NDT) of the surfaces. The condition of the welds
was evaluated by visual inspection, x-ray radiography, and
magnetic particle inspection to document any defects or
irregularities in the material. Pipe thickness surveys were conducted using ultrasonic thickness testing. Additionally, the pipe pieces were laser scanned for complete dimensional documentation.
The fracture surfaces of the ruptured pipe pieces were
examined using low-magnification optical microscopes.
Samples were then cut from the ruptured pipe pieces for
detailed metallurgical examination. The fracture surfaces
were examined under both high-magnification optical
microscopes and scanning electron microscopes to identify
and document specific fracture features. Metallurgists are
currently in the process of using this information to
determine the direction of crack propagation and the
fracture origin and failure mechanisms.
Investigators found that while the longitudinal seams on
some of the pipe segments were fusion-welded from both
inside and outside the pipe, some were fusion-welded only
from the outside of the pipe. In order to understand this
variance, investigators are in the process of researching
pipe welding standards and practices in effect at the time
the pipeline was installed in 1956.
The outer surfaces of the ruptured pipe pieces revealed no
evidence of external corrosion. No dents, gouges, or other
physical indications consistent with excavation damage were observed. Additionally, no physical evidence suggests that a pre-existing leak occurred in the ruptured pipe pieces.
The following laboratory work is ongoing:
Chemical compositional analysis and mechanical property
testing of samples taken from the ruptured pipe pieces.
Evaluation of environmental factors at the accident site.
The investigation is still in an early phase and there is
much factual information to be developed before the Safety
Board is positioned to determine the probable cause of the
accident.
Other areas that investigators are examining include
pipeline control and operations, regulation and oversight,
human performance, survival factors, and pipeline
maintenance and records.
Additional factual updates will be provided and distributed via media advisory as investigative information is developed.
 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

All,

"While it may seem like a small paperwork error, if companies are basing operating pressures on inadequate or erroneous information contained in their records, safety may be compromised," said NTSB Chairman Deborah A.P. Hersman.

Duuhhhhh...!!!!

Nope,... As a practicing Mechanical Engineer the loss or confusion of important design information does not seem like a "small paperwork error" to me Debby....

When you cannot determine the MAOP of an entire pipeline; one that has been operating for 54 years, it is not a small paperwork error....

When innocent people have been burned alive; in thier homes, it is not a small paperwork error....

But perhaps to a "lifetime federal employee" making a large salary looking forward to a huge pension, detailed and accurate welding records means very little.

Anyone ????

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

not disagreeing with you at all . . .

obviously, the gov-trained employee "assumes" the contractor followed design docs/dwgs and "assumes" the inspection records (if any) concur (lacking as-built data) with the design.

i could rant more, but not worth it for now . . .
-pmover

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

bureaucrats aside, they don't do the work, where is the operating company engineer or the inspection protocols

have to say there has been a lot of residential property sold in Tx where the dotted line on the plot plan was glossed over at closing, only for the home owner to discover latter that it was a high pressure pipe line right-of-way...

you wouldn't think a right minded builder or a right minded realtor, or a mortage lender would allow it, but it seems that money changes a lot of attitudes when the risk is beyond the horizon.

Have to say that engineered designs are generally considered unsafe unless they are routinely inspected.     Thats why we have the Boiler Codes...

Amazing failure.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

They are considered safe only at the time of design.  54 years later.... well that's entirely another story.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Hacksaw, let me tell you about TX developers:

Back in the late 80's/early 90's our 2260 psi line went through Friendswood, along with other lines in a cooridor.  A developer came in and set aside the surface near the coridoor as a open space. That developer went belly up and a new developer comes in building smaller and cheaper homes and replats the land with lots ON the pipeline ROW!!!

Friendswood had enacted a law that required that a foundation of a home must be 15 feet from a easment, sounds nice huh?

Nope, our line was less than 10' from the easment edge making the line 15 feet from the homes.

As the homes went up, we glued API signs to the fences over our pieplines.  Needless to say that one homeowner was upset because they had paid the home builder extra money to pour a concrete patio out the back to a point where it would meet the apron of the prefab pool they had bought.

About the same time, our pipeline markers were disapearing as our lines crossed under the grand entry to the subdivision.  I paid a vist to the developer and gave him a copy of the latest DOT rules that increased the fines for removing or damaging pipeline markers, I believe it went up to $25000 from $5000.  He told me that if I and my company interfeered with his business he'd sue us both for millions.  We parted without a handshake that day.

Two weeks later we recieved a letter from a mortgage company asking if we would acknowlege that our pipelines wer covered by DOT safety rules and that we followed the DOT rules.  If we did not, the person could not get an FHA backed loan.  That letter went in to a file cabinet.

I was under no obligation to return the letter timely.  About the same time, people buying homes near high powerlines had to read a report and sign a paper that declared that they understood the dangers of high power lines.

Back to the developers office I went and said that we would not release any information on our pipelines unless he provided an acknowlegment from a buyer that they were aware of our lines.  He refused and nobody could qualify for an FHA loan.  stalemate.  His company went under a year later.
 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

engineering safety, is it ever complete?

Had not heard the Friendswood account, but have been there, beautiful city at least before the floods. In my own case it was in the far northwest of Houston, lots of gas there, and ambition, but I am afraid "let the buyer beware" is not enough. My own family member was fortunate enough to have a license engineer in the family who said wait a minute what's this...threats of suits followed due to refusal to close on the home...ultimately only the earnest money was lost, we were lucky...I can't say that for the ultimate purchaser. Lets see that was in 1980, so in anouther 23 years (54-31), we'll find out how lucky we were...

Have to say any HP gas line, whether 4" or 30" routed under residential property is criminal. I cannot imagine the potential for disaster when the underground sanitary piping goes out.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Again, aside from all of the junior metaphysics of wondering is "anything really safe" the question remails:

What are reasonable rules for high pressure gas mains and what is a reasonable ROW in a residential neighborhood ?

Again, as I stated above:

"At this point in the discussion, it would be interesting to compare the current regulations for USA gas pipe routing to those in Europe."

I am willing to bet that the German gas piping standard is far different than the rules used in California and Texas....

Anybody ?

 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

They seem to be on the trail ... left by somebody else.

Don't really want to use this analogy, but they do say, "Vultures perform a most necessary service."  

Must be a lesson in here somewhere.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

More fun with ancient piping systesms......only a few killed.... this time it's Cast Iron pipe.

http://online.wsj.com/article/SB10001424052748704132204576136011490120274.html?mod=WSJ_hp_MIDDLENexttoWhatsNewsThird

Ill bet that the brutal Pennsylvania cold and the Nil Ductility Transition temperature of ancient Cast Iron will be investigated...

Wait......I can hear it now.....from an MBA at the Gas Pipeline Company.....ACT OF GOD....ACT OF GOD......ACT OF GOD...

 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

so far there is no reporting I have seen which would indicate that a natural gas pipeline leak has been identified as the cause of this unfortunate accident. Assuming it was caused by gas, it could have been a leaking service line, a leaking pipe inside the building or even a missing plug in the gas meter. Probably should hold off on the finger pointing at the old cast iron pipe for a while...

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Many gas utilities don't have a clue what's in its sytems. I remember once finding redwood gas piping still in use after nearly 100 yrs. Or better yet, the steel, low pressure, distribution lines had completely corroded away and the gas containment was the hardened clay originally surrounding it - gas still made it to the residential customers through the still intact risers.  

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

MJC,

I've seen your posts for years in this forum and have found them valuable.

However, it seems that you really have a burr under your saddle about this topic.  Nothing personal, but am I wrong????

I've always worked around a lot of dangerous stuff, high pressure gas, steam, poisionous stuff, rotating machinery, etc as well as having lived right next to HP pipelines - pipelines that blew up within hearing distance of my dwelling on more than one occasion.  I've seen all of it reach out and kill and injure people around me.  Maybe I've just become stoic.

I decided long ago that when the good Lord was ready to take me, He had beau coup different ways to do it.

rmw

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

rmw,

Thank you for your remarks, I also have great respect for your contributions to these fora.

Yes, I do have a bit of a burr under my saddle. I hate liars and managers/bureaucrats who hide behind others.......you should too ! These are the people who will publicly gloss over the real villan here..... a lack of risk based analysis as the piping system ages

Part of my purpose here is to learn something and to flush out the truth about the status of gas pipelines and thier maintenance.

I do not believe that there is adequate and reasonable care taken based on the age and locations of our gas piping infrastructure.

We are going to find that the San Bruno accident involved an ancient pipeline running at the maximum pressure allowed for a new line. Eight human beings barbecued...

A four month old boy was burned to death in Pennsylvania....

Based on the speed everthing else happens in this corrupt state, we will get some kind of report in 2014 calling the accident an act of God....advocating more study and recommending eventual  replacement of piping installed just after World War I.

I guess nobody else seems to get excited about this....

I only hope and pray that the next fire and explosion takes out a Senator or Congressman ..... (CNN and FOX will have many close-ups of the charred carcass) because that seems to be the only way anything productive really happens in the US of A.

Sorry, ...I have been sick lately ...and I only go on eng-tips when I have been drinking...

regards, rmw

-MJC

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

MJC,

I had wondered if maybe you had some relatives involved in the carnage.

But is this any different than electric companies, for example, operating 50-60 year old coal burners that pollute like mad?

They try to build new modern efficient plants with latest technology and the greenies fight them at every turn.

I would think that it is next to impossible to get a new pipeline permitted since most people seem to want nothing in their back yard these days.

So an apathetic public heavily influenced by a bunch of tree huggers seems to bear some of the brunt of the responsibility too, don't they?

rmw

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

rmw and MJC,
Sorry to put my two cents in, but;
As an outsider with very little knowledge of natural gas distribution, it seems to me that there is no reason that this should happen.  The owner of the lines is responsible and any gas line that is run with a strong possibility of causing loss of human life (i.e. in a residential area) should be legally required to have an inspection regime in place and a process in place to replace the lines when deteriorated.
This is the U.S. and there is no excuse for aging infrastructure causing loss of life, as in this case or the I-35 bridge collapse.  As engineers we are all aware of the relationship between perfect safety and economic reality.
rmw,
Although I agree with your assessment of power plant politics, it is spurious to compare a higher pollution power plant, which causes no direct loss of life, with a completely avoidable gas main explosion which instantly causes the death of several people.  

The elected representatives of this country are supposed to be wiser than the rabble who vote for them.  That is why we have a Senate.  I would guess, knowing what lobbyists do, that the natural gas industry has many people whose job it is to schmooze and bribe the Congress to avoid any onerous regulations which would affect the bottom line.  MJC is right.  If this happened to a congressman or his family there would be serious repercussions.  As long as it doesn't happen to the rich or powerful it doesn't matter.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

jgailla,

"natural gas industry has many people whose job it is to schmooze and bribe the Congress to avoid any onerous regulations which would affect the bottom line.  MJC is right.  If this happened to a congressman or his family there would be serious repercussions.  As long as it doesn't happen to the rich or powerful it doesn't matter."

i will ask you to prove your comment.  i know you cannot . . .

do you really think that a pipeline operator (i.e. PG&E or otherwise ) wants to operate an section or portion of pipeline knowing there is a high-risk or non-compliant section of pipeline (San Bruno or otherwise)?  and lobby a politician to avoid responsibility?  get your thoughts corrected forthwith!

hell no!

complacency . . . and ignorant decisions . . . we may never know.  HOPEFULLY, the regulatory agencies will implement changes resulting from these accidents.  no different than the improvements made in the BPVC since the 1850's (boiler explosions on trains).  it may take awhile, but . . .

do not ever think that a loss of life, regardless of social class, age, status, etc. is meaningless.

i am certainly not defending the pipeline operators, but i do believe that no pipeline operator wants to operate an unsafe or high-risk pipeline.  if so, than repercussions await them.  the facts cannot be hidden!

-pmover

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

pmover,

I will have to mostly agree with jgailla on this one, and I can prove it. Although the gas companies aren't interested in purposely blowing anyone up they also aren't interested in seeing greater restrictions on what they can do, and they fight restrictive policy (safety and/or environmental) tooth and nail. There is a long history of the companies and their money influencing bureaucratic policy. Just read the report on the Deepwater Horizon (http://www.oilspillcommission.gov/final-report), particularly Chapter 3. Here's a direct quote from it:

"Revenue generation—enjoyed both by industry and government—became the dominant objective. But there was a hidden price to be paid for those increased revenues. Any revenue increases dependent on moving drilling further offshore and into much deeper waters came with a corresponding increase in the safety and environmental risks of such drilling. Those increased risks, however, were not matched by greater, more sophisticated regulatory oversight. Industry regularly and intensely resisted such oversight, and neither Congress nor any of a series of presidential administrations mustered the political support necessary to overcome that opposition. Nor, despite their assurances to the contrary, did the oil and gas industry take the initiative to match its massive investments in oil and gas development and production with comparable investments in drilling safety and oil-spill containment technology and contingency response planning in case of an accident."

Regards,
K
 

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Risk assessment is often problematic with respect to costs incurred from potential damage, injury, loss of life, etc. especially when the costs of inspection, testing, replacement are highly quantifiable.

Many years ago, I was able to dissuade operations from their desire to substantively increase operating pressure on old gas pipelines which crossed major faults and which were subject to major earth quakes thereon and were subject to known subsidence and earth slides. I was also acutely aware of the flaws(now rejectable) inherent in the long seams of pipe manufactured in the early 1950's. With today's emphasis on the quantifiable bottom line, it might be much more difficult to adequately (in the bean counters' eyes) do do the same.  

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Thank you all for your contributions...

Sometimes, it is only by making an extreme point that the true feelings of professionals can be teased out.

I would like to hope that the San Bruno accident will eventually result in a change of regulation and not be forgotten.

Just recently, PG&E decided to reduce operating pressure in high hazard sections of thier system

Perhaps a program of intensive inspection and replacement of all piping (over say...um 40 years old) in high hazard areas would be reasonable.

We are going to only use more natural gas, at higher pipeline pressures. MBAs will only be under more pressure to trim corners and push the system to it's limits.

RMW, I have visited and worked at old fossil poer stations where boiler tubes have failed. It is only the people who have consented to work at the station who are injured....not children asleep at home....

Again, thank you....all

regards

MJC

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Update......Update....  April 05 2011 !!!!

Government officials have finally recognized that there is a problem and are "unveiling a plan" !!!!

WHHHHHOOOOOOO !!!!!

"We're going to be very aggressive on this," Transportation Secretary Ray LaHood said in unveiling his plan, though he acknowledged that many of the details have yet to be worked out. Among the unanswered questions is what it might cost to upgrade the nation's pipeline network and who would pay for it.

"We're trying to work with the pipeline companies to assess what it is they believe needs to be replaced," he added, noting that his agency will hold a pipeline safety forum April 18 in Washington to hash out such issues. "We'll figure out what it costs."

Some pipeline experts generally applauded the move. But they noted that key elements of the plan -- including raising the maximum daily fine from $1 million to $2.5 million -- already are proposed in pending federal legislation and said they would reserve judgment until more about LaHood's ideas are revealed.

Does this sound like the US FEDERAL GOVENMENT ?????

WE HAVE A PLAN !!! ( But most details have yet to be worked out..)

http://www.mercurynews.com/bay-area-news/ci_17769040?nclick_check=1

As you read the article.....note that the only item of substance in the proposed plan by the Transportation Secretary is to RAISE THE AMOUNT OF THE DAILY FINE...!!!

It makes me proud to be an American ......  


Anyone ???

 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

I think the only unanswered question is what it might cost to upgrade.  I'm relatively certain, within all margins of error, who will pay for it.

 

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

A million dollars a day, or a billion dollars a day, is not an incentive if you never bother to collect it.

It smells like ol' Ray is going to get maneuvered into making US pay for fixing up the decrepit pipelines.  


Toyota is now advertising its product as 'NASA certified'.  Unbelievable.

Where does Barack get these people?  Or is it the air inside the Beltway?

 

Mike Halloran
Pembroke Pines, FL, USA

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

My first guess is that it probably won't be the stockholders... not even in the beginning.

Let your acquaintances be many, but your advisors one in a thousand'  ...  Book of Ecclesiasticus

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Another update:   June 10th 2011

"California Orders Utilities to Test or Replace Old Gas Lines"

"The 55-year-old pipeline that ruptured last September in San Bruno, California, had welding flaws, federal investigators have said. PG&E had also misidentified its construction design and poor record keeping on pipelines could mean a line is operated at a higher pressure than it is built to withstand, investigators said.

Pipelines installed before 1962 were not required by state law to have pressure testing"

http://www.bloomberg.com/news/2011-06-09/california-orders-utilities-to-test-or-replace-old-gas-lines.html

Hhhhhmmmm.......

Test or replace old piping ???

Who would have suspected ??? !!!!

 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

And it only took those Californicating genius statesmen 7 monthe to figure out the obvious.  At least no more disasters have happened in that time.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Another update !!!

Looks like there is a preliminary conclusion that it was sewer work that caused the San Bruno explosion.

http://www.mercurynews.com/science/ci_18244524?source=rss

The expected cawing and braying of elected officials cuts through the night:(Rep. Jackie Speier, D-Hillsborough)


"PG&E failed to have a supervisor present during the sewer project located by the segment of pipe that eventually ruptured," she said. "If PG&E had done its job, the assumption is that it would have witnessed the patchwork construction on its pipeline and that, in turn, would have triggered an immediate inspection, if not repair. Instead, eight people died."

I revise my equation above:

Old piping standards + 54 years + unknown pressure surges + California real estate market + Lawyers and CA politicos = disaster snd death

Wait for the next one......


 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Well PG&E should have had an inspector at site for this ground distrubance. But speaking from experience, it probably wouldn't have prevented the explosion. Typically it will be someone in operations watching this type of work with no experience or knowledge in integrity. They would essentially be there to make sure the third party doesn't hit the pipe. Unfortunately, that's about as in depth of supervision these inspectors provide.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

For some great pictures see:

http://en.wikipedia.org/wiki/2010_San_Bruno_pipeline_explosion

Lawyers are dancing........ In a bizzare California twist:

"In its court filing, PG&E also said the blast victims themselves "may have been legally responsible under a doctrine of comparative negligence (or) contributory negligence" - factors that assign a portion of blame to a plaintiff.

PG&E's filing did not specify how residents might have been negligent, or how that negligence contributed to the fireball that consumed their homes."

It's too bad that this legal tactic cannot be explained to those victims who were burned beyond recognition in thier homes by the 1000 ft high fireball

PG&E claims that they had a "state of the art" piping system.

You be the judge....does the system need to change ?

What about other states ?

For example, do the jobs-for-life slugs working for the Commonwealth of Pennsylvania need to change thier inspection program ?
            
            
            
            
            
            
 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

I'm guessing that they'll argue that most of the residents ignored the smell from the gas leaking from their pipeline, and therefore contributed to the lack of urgency on PG&E's part to repair the leak.  Obviously, if there are few complaints, it can't be a big enough problem, right?

Additionally, the increase in population in the area would have "forced" PG&E to run the pipe at a higher than recommended pressure, to supply sufficient gas for the usage demand.  Since the customer demanded the increase in gas supplies, they must have implicitly borne the increased risk to the pipeline.

TTFN

FAQ731-376: Eng-Tips.com Forum Policies
Chinese prisoner wins Nobel Peace Prize

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

New Developments !!!

At near lightning speed, the NTSB completes its one-year investigation !!!

Grandfathering by Accountants Kills yet Again !!!

http://www.allheadlinenews.com/articles/90058686?Federal%20probe%20on%20San%20Bruno%20blast%20blames%20PG%26E%20pipeline%20management

"The NTSB also cited federal and state regulators for allowing the "grandfathering" of pipes that lets companies operate older lines without performing hydrostatic pressure tests that expose defects.

The California Public Utilities Commission permitted grandfathering beginning in 1961 while the U.S. Department of Transportation did the same in 1970.

The NTSB previously found that PG&E had listed the San Bruno line as constructed of seamless pipe when in fact the line was made of six sections of seam-welded pipes.

Fabrication of five of the sections would not have met safety protocols when the line was installed five decades ago, while the sixth section was the visibly defective pipe that burst, the agency said.

The internal line pressure before the explosion did not exceed the maximum allowable pressure for the pipeline and would not have caused an accident if the line had been properly constructed."

http://www.ntsb.gov/news/events/2011/san_bruno_ca/index.html




 

   

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

PG&E president Chris Johns said in a statement his company  "fully embrace[s]" the findings.

"Because we firmly share the Board's commitment to seeing that such a terrible accident never happens again, we are grateful for its meticulous review of evidence, finding of facts and thoughtful recommendations," he said.


Horseshit.  PG&E does not seem to intend to ever hydro-test their existing ancient untested lines, relocate pipe to non-residential areas, or run "smart pigs" through their ancient lines and then dig at the 'suspect' and 'bad' areas identified by the 'smart pigs'.

If they never test, then they don't OFFICIALLY "know" that there are problems.  And since they don't "know" of any problems, they have no requirement to repair, replace, or reroute any pipelines.  Looks like the lawyers and accountants have wone this round.  Like usual.

Now we get to wait to see if the next big leak kills fewer, or more people, than the San Bruno one did.  

This is probably how the ASME Boiler committes folks felt from its founding in 1911 on thru the 1930's, when ASME was "recommended" but not mandatory.  Boilers kept exploding and people kept dying, culminating in a few horrific school explosions in the 1920's and 1930's.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

2
Just remember: government is bad, regulations are bad, big business is good.  And go drink some tea.

I should probably red flag this as it's a political statement -- but what do people expect when that's the US political philosophy these days?

Patricia Lougheed

******

Please see FAQ731-376: Eng-Tips.com Forum Policies: Eng-Tips.com Forum Policies for tips on how to make the best use of the Eng-Tips Forums.

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

tea sounds good to me, regulaton is bad until you findout why we need them, but they have to have teeth in them, safety is cheap when the real cost is tallied

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

The need for more regulation is implicit whenever more profit is the sole motivating factor.

We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us.  Lisa Gansky

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

I avoided this thread while it was active, but a client in CA asked me what code changes would this disaster cause to happen.  I decided to read the thread before going much farther.  It developed pretty much the way I expected when I decided to avoid it.

One recurring theme above is that companies are money-grubbing slime that don't care about public safety.  PG&E is going to spend a couple of billion dollars defending and settling the lawsuits.  There was no doubt that that would be the outcome of a major failure, and that a major failure was inevitable.  They knew it decades ago.  Their half-hearted efforts to avoid something like San Bruno met with regulatory and environmental resistance and it didn't take much resistance to cause them to divert the repair funds to executive compensation.  

I saw an internal analysis from another interstate pipeline operator done in 1989.  Their conclusion back then was that testing/repairing/replacing the High Consequence piping should be a priority (22 years ago) and they started down that road only to find that shutting down a 30" high pressure line for two weeks to test it WOULD NOT BE ALLOWED BY REGULATORS because the disruption of supply would cause "unreasonable hardship" (direct quote from a California regulator) on consumers.  I'm serious.  The company also looked at replacing sections that had evolved from unpopulated land to under an elementary school playground--the greenies blocked every alternative route, gotta protect the snail darter and spotted owl.  A decade after the report I saw very little had been done because of insurmountable barriers not the bottom line.

Companies make decisions that suck.  Always have.  Always will.  But when companies try to do the right thing they're blocked by regulators who are trying to do the right thing (for themselves and their patron's reelection) and misguided environmentalists who see any industrial activity as evil.  It doesn't take much obstructionist nonsense to cause a company to revisit the cost benefit analysis and say that a couple of billion in law suits and legal fees is a cost of doing business since they are not allowed to fix the problems.

David

RE: San Bruno 30" Natural Gas Transmission Line, -FAIL-

Bravo zdas04.....

But, everyone should note that PG&E has finally decided to get off of thier dead asses an attempt to become responsible:

http://www.pge.com/myhome/edusafety/systemworks/gas/pipelinesafety/

In my post above, on 12 Sept 2010, I said:

"To what standard and HOW OFTEN ARE THESE MAINS INSECTED ?"

It appears to me that CA utilities/regulators make up thier own inspection and testing standards and change them at whim...

Little comfort for those burned alive....





 

   

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources