Following the intense gas-transmission line fire that started last night at San Bruno, CA: a local article is here.
This article from the San Jose Mercury says it was an 8-alarm fire and the radiant heat was enough to ignite furniture through a plate glass window.
In a Time blog on "natural gas industry under new scrutiny," there's a map of the pipelines feeding into CA.
Natural gas is a rare energy source in that (until the hydro-fracking controvery, anyway) it has generated little concern on a national level although there have been some catastrophic events on a local scale and a number of regional controversies about proposed LNG terminals.
Big gas-line breaks are statistically rare but release a great deal of energy.
Causes are usually construction machinery damage or corrosion. One of the worst US gas-line blasts caused was due to untended corrosion and caused fatalities at a camping site on the Pecos River near Carlsbad, NM, in 2000. The NTSB report on that one is here.
Friday, September 10, 2010
Wednesday, September 8, 2010
BP's Story
BP is distributing its version of events: full PDF is here.
It's a mix of lawyerly conclusions (BP's errors are characterized as forgivable ones of inadequate communications across work teams and faulty analysis of test results), some rather blurry diagrams, and many pages of extremely technical material about well control and design. A subsea engineer could follow it but the rest of us struggle.
Even BP execs would be hard pressed to say that it's a complete and convincing picture. For one thing, the report predates the recent recovery of the BOP -- and the BOP hasn't been taken apart and studied yet -- so a disaster report from BP is premature.
But rather than get into a book review, let me suggest that detail-hounds check out some descriptions of key hardware (such as the MUX reels to control the BOP and how they may have been damaged in the blast, accumulators to energize the rams and how they're normally recharged, the twin control pods, and how fault reporting on the BOP alarm board didn't alert the subsea engineer to weak batteries), fault trees, and new detail about events not previously reported.
On pp 163-166 is a description of pipe anomalies in the BOP, which includes a mention of the "drift-off" that must have occurred after the explosion, before the rig sank, and what it likely did in bending the riser above the blowout preventer.
Drift-off is when a floating rig loses power and ocean currents or winds try to drag it off station, while it is still connected via the riser to the BOP and wellhead. Since dynamically positioned deepwater rigs like the DH have no anchor lines to keep them on station, a loss of power to the thrusters puts a strain on the drill string, even in calm weather. As I read the report, the DH's drift-off began to drag drill string up and out of the wellhead. Has that ever happened before?
Also there's a photo of a section of deeply striated tool joint, apparently eroded by the enormous flow of sand, gas and fluids up the wellbore.
Also catching my eye was mention of ROV operations, undertaken before the rig sunk, in hopes of forcing the rams to close off the blowout. It didn't work but that must have been a time of high drama, and high frustration.
It's a mix of lawyerly conclusions (BP's errors are characterized as forgivable ones of inadequate communications across work teams and faulty analysis of test results), some rather blurry diagrams, and many pages of extremely technical material about well control and design. A subsea engineer could follow it but the rest of us struggle.
Even BP execs would be hard pressed to say that it's a complete and convincing picture. For one thing, the report predates the recent recovery of the BOP -- and the BOP hasn't been taken apart and studied yet -- so a disaster report from BP is premature.
But rather than get into a book review, let me suggest that detail-hounds check out some descriptions of key hardware (such as the MUX reels to control the BOP and how they may have been damaged in the blast, accumulators to energize the rams and how they're normally recharged, the twin control pods, and how fault reporting on the BOP alarm board didn't alert the subsea engineer to weak batteries), fault trees, and new detail about events not previously reported.
On pp 163-166 is a description of pipe anomalies in the BOP, which includes a mention of the "drift-off" that must have occurred after the explosion, before the rig sank, and what it likely did in bending the riser above the blowout preventer.
Drift-off is when a floating rig loses power and ocean currents or winds try to drag it off station, while it is still connected via the riser to the BOP and wellhead. Since dynamically positioned deepwater rigs like the DH have no anchor lines to keep them on station, a loss of power to the thrusters puts a strain on the drill string, even in calm weather. As I read the report, the DH's drift-off began to drag drill string up and out of the wellhead. Has that ever happened before?
Also there's a photo of a section of deeply striated tool joint, apparently eroded by the enormous flow of sand, gas and fluids up the wellbore.
Also catching my eye was mention of ROV operations, undertaken before the rig sunk, in hopes of forcing the rams to close off the blowout. It didn't work but that must have been a time of high drama, and high frustration.
Tuesday, September 7, 2010
Offshore Workers' Heli-Phobia
Read a Men's Journal piece out on the Deepwater Horizon, "The Well from Hell." Readers may puzzle at a comment to the effect that offshore workers rank helicopter travel near the top of their fears. I came across this opinion also, when researching the loss of the Ocean Ranger rig off Canada.
The main reason for the workers' worry is that helicopters tend to roll over soon after ditching in an emergency. This can happen very quickly, so each passenger must unbuckle and find his way out of a flooding, crowded, inverted, dark compartment at the same time that other highly motivated people are trying to do the same. Although there is time to do it right (a flipped aircraft doesn't sink like a stone, even when the doors are open) but people who heard a safety briefing beforehand sometimes forget this in the excitement. The challenge is compounded greatly if this happens in a storm in frigid seas because the survivors must also find and don their survival suits, before the helicopter sinks. There are companies that train offshore workers specifically in how to get out of an inverted helicopter in the water.
Why do standard copters tend to roll over in the water? Think of the difference in how weight is distributed in an airplane compared to a helicopter. The heaviest portions of an airplane are the engines, payload, fuel, wings, and the landing gear assembly. In airplanes these are near the center of gravity or below. But a transport helicopter carries some heavy iron above the CG: commonly powerplant, transmission, main rotorhead, and main rotor blades. In short, it's top-heavy.
The most likely rotorcraft to stay upright in the water are ones with permanent flotation gear like Navy Sea King rescue helicopters. But the helicopters the offshore workers are worried about aren't the Sea Kings - they're worried about commercial transport helicopters that roll over after ditching.
The main reason for the workers' worry is that helicopters tend to roll over soon after ditching in an emergency. This can happen very quickly, so each passenger must unbuckle and find his way out of a flooding, crowded, inverted, dark compartment at the same time that other highly motivated people are trying to do the same. Although there is time to do it right (a flipped aircraft doesn't sink like a stone, even when the doors are open) but people who heard a safety briefing beforehand sometimes forget this in the excitement. The challenge is compounded greatly if this happens in a storm in frigid seas because the survivors must also find and don their survival suits, before the helicopter sinks. There are companies that train offshore workers specifically in how to get out of an inverted helicopter in the water.
Why do standard copters tend to roll over in the water? Think of the difference in how weight is distributed in an airplane compared to a helicopter. The heaviest portions of an airplane are the engines, payload, fuel, wings, and the landing gear assembly. In airplanes these are near the center of gravity or below. But a transport helicopter carries some heavy iron above the CG: commonly powerplant, transmission, main rotorhead, and main rotor blades. In short, it's top-heavy.
The most likely rotorcraft to stay upright in the water are ones with permanent flotation gear like Navy Sea King rescue helicopters. But the helicopters the offshore workers are worried about aren't the Sea Kings - they're worried about commercial transport helicopters that roll over after ditching.
Monday, September 6, 2010
Shaped charges, and a call for new engineers
In the last five years when researching stories on technology I've commonly heard concerns from industries about a demographic crisis in getting enough people with specialized training, now that old hands are retiring: such as inert gas welding, underwater engineering, numerically controlled machinery, and explosives. Here's a Wash Post article where this concern has come up in air traffic control. Sort of a "human infrastructure" crisis.
When researching my piece on shaped charges, I heard from both the explosives companies and the mining school at Rolla, Missouri, that there's a strong demand for young explosive engineers. If you know of high-schoolers interested in the subject, have them take a look at Rolla's summer school in explosives. I interviewed Prof. Paul Worsey of Rolla ... very helpful! Here's a link to his series on explosives for Discovery.
Re: shaped charges, here's a Wikipedia link ... the penetrating effect comes not from a jet of "white hot plasma" but rather in how it forges a rod of metal from a sheet of metal (it's hot, but not necessarily molten) and projects it forward at supersonic speed. When striking armor plate, this rod actually shoves aside molecules of metal in the armor and opens a cavity in the direction of travel. In a 1997 military test, one shaped charge opened a hole through 11 feet of armor plate. Numerically, the vast majority of shaped charges now manufactured are pocket-sized devices used in the oil and gas industry, quite effective at perforating steel pipe and opening up rock formations to production.
For armchair historians interested in the history of the WWII bazooka (a marriage of the shaped charge warhead and the solid fuel recoilless rocket), here's an excerpt from my article. Two things to note: first, the M1 was not a great antitank weapon but still proved its worth in taking out pillboxes and giving heart to our infantry; second, how very quickly industry was able to produce the weapons in quantity (GE had 30 days from working out the first prototype manufacturing article, to finishing the production run). I might add some posts in the future on lessons in rapid production from WW2, by far the most productive period in US history.
When researching my piece on shaped charges, I heard from both the explosives companies and the mining school at Rolla, Missouri, that there's a strong demand for young explosive engineers. If you know of high-schoolers interested in the subject, have them take a look at Rolla's summer school in explosives. I interviewed Prof. Paul Worsey of Rolla ... very helpful! Here's a link to his series on explosives for Discovery.
Re: shaped charges, here's a Wikipedia link ... the penetrating effect comes not from a jet of "white hot plasma" but rather in how it forges a rod of metal from a sheet of metal (it's hot, but not necessarily molten) and projects it forward at supersonic speed. When striking armor plate, this rod actually shoves aside molecules of metal in the armor and opens a cavity in the direction of travel. In a 1997 military test, one shaped charge opened a hole through 11 feet of armor plate. Numerically, the vast majority of shaped charges now manufactured are pocket-sized devices used in the oil and gas industry, quite effective at perforating steel pipe and opening up rock formations to production.
For armchair historians interested in the history of the WWII bazooka (a marriage of the shaped charge warhead and the solid fuel recoilless rocket), here's an excerpt from my article. Two things to note: first, the M1 was not a great antitank weapon but still proved its worth in taking out pillboxes and giving heart to our infantry; second, how very quickly industry was able to produce the weapons in quantity (GE had 30 days from working out the first prototype manufacturing article, to finishing the production run). I might add some posts in the future on lessons in rapid production from WW2, by far the most productive period in US history.
By late 1941 the Army had a lightweight warhead able to destroy the era's lightly skinned tanks, but it lacked a delivery system with which an infantry-man could confront an oncoming tank. Meanwhile, two American Army officers had overcome all hurdles to build a workable shoulder-fired rocket launcher. But they had no lightweight, armor-busting warhead to fire. Soon thereafter these two projects would intersect and spawn almost a half-million offspring known as bazookas.
The search for an effective shoulder- fired rocket launcher had begun long before, most notably in 1866 with the pyrotechnics manufacturer Gustavus Adolphus Lilliendahl and the one- armed whaling captain Thomas Roys, who began selling a shoulder-launched rocket system. It fired an explosive- tipped rocket intended to harpoon whales at distances up to 130 feet. In both appearance and function, the whaling rocket was a closer kin to the eventual bazooka than the solid-fueled, man-portable launch weapon developed by the rocket pioneer Robert H. Goddard during the First World War.
Unfortunately for Goddard, the Armistice came less than a week after he demonstrated his rocket, and the Army declined to proceed. After recovering from tuberculosis, Goddard shifted to liquid-fueled rocket research. But his coworker, graduate student Clarence N. Hickman of Clark University, continued in the field. (During the war, the university would support more rocket research at its Allegany Ballistics Laboratory in Rocket Center, West Virginia.) And in 1931 the Army detailed Maj. Leslie Skinner to serve as a one-man rocket research center. Skinner's program doubled with the addition of Lt. Edward Uhl, expanding again in 1940 after Hickman pointed the new National Research Defense Committee toward rocket research. Working in a basement lab at George Washington University, Uhl and Skinner progressed from a closed launcher with tremendous recoil to an open- ended tube that allowed each rocket to discharge its exhaust out the back.
Top Army Ordnance officials happened to be visiting Aberdeen in May 1942, when Skinner and Uhl were firing their prototype at a moving target. Although the launcher only mounted dummy warheads, the flame and whoosh drew their attention. Skinner gamely let them test-drive it even with its rudimentary gunsight. On his first try, Gen. Gladeon Marcus Barnes, who headed weapons research and development at Ordnance, hit the target squarely. “The other staff people fired until all our rounds were gone,” Skinner would recall. “Right there and then the Bazooka was ordered into pilot production design.” In one of the fastest procurement decisions ever, the Army contracted a few days later with General Electric for 5,000 M1 launchers, and with Edward G. Budd Manufacturing Company for 25,000 M6 rockets employing a shaped charge like that in the M9 rifle grenade.
The companies had 30 days to deliver. By 1942 much American war production happened at a sprinter's pace, but this particular job gave a new meaning to “rush order.” Working 24 hours a day, General Electric engineers spent more than two weeks building and testing a dozen prototypes before the Army approved a production model. That left eight days for a converted refrigerator factory in Bridgeport, Connecticut, to turn out the goods. The supply chain included police officers who picked up pieces at the airport, hurled them in the trunks of their squad cars, and raced to the factory. General Electric finished with 89 minutes to spare.
At first the troops dubbed it the “Buck Rogers gun” but then settled on “bazooka,” because it resembled a musical instrument of the same name that movie and radio comedian Bob Burns had improvised out of pipe. The tube was made long so that the propellant would have burned out by the time the rocket left the tube, thus avoiding injury to the operator's face by exhaust flame. The Army's publicity machine was quick to celebrate this paragon of American ingenuity: the bazooka was a miracle weapon, Ordnance chief Gen. L. H. Campbell Jr. told reporters in March 1943, enabling any GI “to stand his ground with the certain knowledge that he is the master of any tank which may attack him.”
In truth the early bazookas fell short of actual panzer-stopping power. Commanding officers, including Lt. Gen. James Gavin, reported back to Ordnance that German tanks had flattened GIs who had stood their ground. Moreover, the rush of battle easily damaged the long tube. The battery circuit wasn't reliable, many troops lacked training, and some rockets misfired or bounced off their targets. But even the early M1 models were good pillbox wreckers; after the M9A1 was available, Allied soldiers were able to disable light and medium tanks, some-times working in concert with tracked tank destroyers. All told, American companies produced 441,000 bazookas and 15 million rocket warheads.
After the bazooka appeared, the Germans fielded their own tank- busting rockets: the shoulder-fired Panzerschreck (tank terror) and the short-range, single-use Panzerfaust (tank fist). Franz Thomanek insisted after the war that these were no mere knockoffs of the M1 and M9 bazookas. (This is probably true in the case of the Panzerfaust.) In any case, most GIs who tried both German and American models agreed that the bigger German weapons inflicted more damage than their 2.36-inch-diameter counterparts.
Reacting to the competition, the Army commissioned the M20 Super Bazooka, but this did not materialize in time for World War II, even arriving a bit tardily on Korean battlefields. Task Force Smith and other American units first thrown into action against the North Korean 105th Armored Brigade found that their war-surplus M9A1 bazookas had no effect on the Russian-built T-34s. On its arrival in September 1950, however, the Super Bazooka helped turn the tide, remaining in use until the one-shot, disposable M72 Light Antitank Weapon replaced it during the Vietnam War.
Saturday, September 4, 2010
From Red Flags to Torpedoes
Railroads switched from flagmen to automatic block signals long ago, so it's time to freshen up some metaphors, particularly the shopworn red flag of danger. If an editorial writer is trying to make the point that some earlier incident should have given regulators a clear warning about some company's recklessness long before things blew up, he could toss out the red flag and say instead, “There was a torpedo right there on the track but the agency rolled over it and kept on going.” Laid on a rail to warn of sure danger ahead and detonated by pressure, torpedoes were flat, round noisemakers that would detonate with a cannon-like report at the first touch of a locomotive wheel. An engineer might miss noticing a man on the right of way waving a red flag, but he wouldn't miss the sound of a torpedo.
"That project was a complete train wreck that took out all the investors" could be freshened up to "That whole project was a snakehead." In the early decades of railroading, a rail was not the sturdy round-topped bar of rolled steel we know today, but a long board laid on its edge and topped along its length with a wrought-iron strap, nailed on. Sometimes one end of a strap worked loose and bowed upward as a train was rushing by. If snagged by running gear the iron bar would fly loose and smash through the wooden floor of a moving coach, killing or maiming all passengers within reach, however wealthy. So when a big pyramid scheme goes bust and takes out hundreds of families' savings, that's a snakehead.
"His reputation is shot" could be railroadized to "His reputation is on the hammer track." That's a salvage siding used for tearing apart old boxcars and locomotives.
"That project was a complete train wreck that took out all the investors" could be freshened up to "That whole project was a snakehead." In the early decades of railroading, a rail was not the sturdy round-topped bar of rolled steel we know today, but a long board laid on its edge and topped along its length with a wrought-iron strap, nailed on. Sometimes one end of a strap worked loose and bowed upward as a train was rushing by. If snagged by running gear the iron bar would fly loose and smash through the wooden floor of a moving coach, killing or maiming all passengers within reach, however wealthy. So when a big pyramid scheme goes bust and takes out hundreds of families' savings, that's a snakehead.
"His reputation is shot" could be railroadized to "His reputation is on the hammer track." That's a salvage siding used for tearing apart old boxcars and locomotives.
Friday, September 3, 2010
NPR's summer jobs series
Enjoyed this series a lot, and the way it gave listeners the opportunity to speak for themselves. My jobs through graduation: construction work, haying, summer camp counselor and cook, freight handler in an oil warehouse, roofer, bus driver, law clerk, freelance writer, and a brief stint of logging in Missouri and mining in New Mexico.
Most miserable times on a job: installing fiberglass insulation in an attic in July 1980 – it was so hot that I started feeling cool and knew it was time to get out. Flip side of that: standing in a January blizzard in North Dakota as a reporter, watching tower hands stumble around trying to find structural steel in hard-packed drifts. Their Bobcat kept running into buried steel so they gave it up.
Though I had on every bit of arctic gear I had bought while living in Fairbanks, Alaska, the 30-mph wind was cutting through every gap and I was delighted to head for shelter when they did.
Sounds dangerous but wasn't really: working with high explosives on a construction job. As long as some critical mistakes are avoided, modern nitrate explosives (we used DuPont's Tovex, plus detonating cord for the primers) and electric detonators are quite safe to handle. Odd fact: when a cartridge is cut open, Tovex has the appearance of tapioca pudding.
Sounds risky and it was: Most dangerous five minutes had to be riding on an MD 500 helicopter with a power line maintenance crew in Pennsylvania. Their job was to replace metal spacers that separate the conductors of a high voltage power line. I think of it as hazardous not because the powerline was energized (it was, at 230Kv), or because the crew lacked skill (they were very good) but because the situation had no room for error or malfunction.
Normally, almost any industrial operation has enough slack – call it margin of error -- that one mishap doesn't turn into a disaster, but this job had no slack. It was a single engine helicopter hovering at a low altitude, so an engine failure or rotor strike was guaranteed to end in a crash; the work required the pilot to hover the left side of the aircraft within a foot of the power line with his main rotor overlapping the line, and the tail rotor within two feet; and as an observer I didn't get a crash-rated seat. The pilot had a military-style model with shock absorbers to cushion a vertical impact and save helicopter pilots from permanent back injury (think compressed vertebrae) in the case of a crash, but in the back seat I had a plywood special. Anyway, it was a thrilling chance to see experts at work and it turned out fine but it's not something I would want to do on a regular basis.
Stuff I'd have to do more to be safe: cutting down trees with a chain saw. Even with all the safety devices and PPE this takes constant attention and I found when I got tired the odds of a mistake went way up. The mishaps I've had have been comparatively minor (except for one cut that got infected and took some special antibiotics.) The dilemma is that it takes a lot of hours to be good, but using one for lots of hours is also risky. I can see why logging is one of the riskiest jobs there is.
Most motivated moment: my brothers and cousin Rich had the chance to do some drilling on a mountaintop in New Mexico, for a gold company that needed work done so as to hold its claim. Our job was to get up there towing an air compressor and use a jackleg to drill holes in the rock face and collect rock samples to bring back. The compressor was a good sized one and burned a lot of gasoline so we brought along a drum of fuel, which we decided to leave chained upright on the back of the truck since it weighed about four hundred pounds. One night a thunderstorm came up and we realized at about the same moment that the pump handle on the drum would act a lot like a lightning rod once rain started, which would put water on the tires and act as a ground. The next thought: the image of a fireball in the middle of our camp, like in the movies. With one mind we piled out of our sleeping bags and divided up the work: One man to unscrew the pump and close up the hole with a bung, two guys to clear a path through the junk on the flatbed, and one to round up a pair of timbers so we could roll it off. Within two minutes we had the drum off the truck and laying sideways in the lowest spot available. Teamwork!
Most miserable times on a job: installing fiberglass insulation in an attic in July 1980 – it was so hot that I started feeling cool and knew it was time to get out. Flip side of that: standing in a January blizzard in North Dakota as a reporter, watching tower hands stumble around trying to find structural steel in hard-packed drifts. Their Bobcat kept running into buried steel so they gave it up.
Though I had on every bit of arctic gear I had bought while living in Fairbanks, Alaska, the 30-mph wind was cutting through every gap and I was delighted to head for shelter when they did.
Sounds dangerous but wasn't really: working with high explosives on a construction job. As long as some critical mistakes are avoided, modern nitrate explosives (we used DuPont's Tovex, plus detonating cord for the primers) and electric detonators are quite safe to handle. Odd fact: when a cartridge is cut open, Tovex has the appearance of tapioca pudding.
Sounds risky and it was: Most dangerous five minutes had to be riding on an MD 500 helicopter with a power line maintenance crew in Pennsylvania. Their job was to replace metal spacers that separate the conductors of a high voltage power line. I think of it as hazardous not because the powerline was energized (it was, at 230Kv), or because the crew lacked skill (they were very good) but because the situation had no room for error or malfunction.
Normally, almost any industrial operation has enough slack – call it margin of error -- that one mishap doesn't turn into a disaster, but this job had no slack. It was a single engine helicopter hovering at a low altitude, so an engine failure or rotor strike was guaranteed to end in a crash; the work required the pilot to hover the left side of the aircraft within a foot of the power line with his main rotor overlapping the line, and the tail rotor within two feet; and as an observer I didn't get a crash-rated seat. The pilot had a military-style model with shock absorbers to cushion a vertical impact and save helicopter pilots from permanent back injury (think compressed vertebrae) in the case of a crash, but in the back seat I had a plywood special. Anyway, it was a thrilling chance to see experts at work and it turned out fine but it's not something I would want to do on a regular basis.
Stuff I'd have to do more to be safe: cutting down trees with a chain saw. Even with all the safety devices and PPE this takes constant attention and I found when I got tired the odds of a mistake went way up. The mishaps I've had have been comparatively minor (except for one cut that got infected and took some special antibiotics.) The dilemma is that it takes a lot of hours to be good, but using one for lots of hours is also risky. I can see why logging is one of the riskiest jobs there is.
Most motivated moment: my brothers and cousin Rich had the chance to do some drilling on a mountaintop in New Mexico, for a gold company that needed work done so as to hold its claim. Our job was to get up there towing an air compressor and use a jackleg to drill holes in the rock face and collect rock samples to bring back. The compressor was a good sized one and burned a lot of gasoline so we brought along a drum of fuel, which we decided to leave chained upright on the back of the truck since it weighed about four hundred pounds. One night a thunderstorm came up and we realized at about the same moment that the pump handle on the drum would act a lot like a lightning rod once rain started, which would put water on the tires and act as a ground. The next thought: the image of a fireball in the middle of our camp, like in the movies. With one mind we piled out of our sleeping bags and divided up the work: One man to unscrew the pump and close up the hole with a bung, two guys to clear a path through the junk on the flatbed, and one to round up a pair of timbers so we could roll it off. Within two minutes we had the drum off the truck and laying sideways in the lowest spot available. Teamwork!
INPO - the magic bullet?
Saw a string of articles in mid-August about INPO (Institute of Nuclear Power Operators) as a potential breakthrough model for improving offshore rig safety. Presidential commission chair Bill Reilly says he likes the idea. INPO harnesses the "enlightened self interest" of the nuclear industry to assist with some self-policing, since all operators are going to be threatened by one disaster. INPO reviews each power reactor every two years and delivers a confidential report to the operator that can be blistering. All in all, INPO has proved its worth.
An INPO-like group for offshore oil is worth considering as an adjunct to regulation by a non-industry-controlled agency, but there would be problems in transferring the model to offshore oil and it's not a miracle worker. Two words to make the point that INPO can't do everything: the Davis-Besse nuclear power plant at Oak Harbor, Ohio. In 2002 maintenance work to check nozzles at a difficult-to-reach portion of the reactor pressure vessel at Davis-Besse coincidentally revealed that boric acid corrosion had over the course of years eaten a football-sized hole through more than six inches of steel, leaving less than half an inch of stainless steel to contain the steam pressure inside.
This was an extremely serious lapse in safety by the operator FirstEnergy, despite multiple warnings that boric acid corrosion if neglected could cause a loss of coolant accident. It was coincidence that caught the problem, not INPO or the NRC.
INPO visits have merit because they offer more expertise and more independence than the NRC or most companies have been able to muster, but they can't substitute for what the operator should be doing.
The other limitation of the INPO model when it comes to deepwater oil is the difficulty of cross-inspection by an outside industry team. How would such a team evaluate a new combination of methods, never tried on any rig before? How would they have been able to comment on the maintenance needs of MUX-style blowout preventers versus hydraulic ones, when the former came into use?
Compared to the deepwater oil play, boiling water reactors and pressurized water reactors are a mature technology. In deepwater exploration and production the methods are changing all the time, the operating environment is dynamic rather than controlled, and much of the equipment is inaccessible to inspection.
An INPO-like group for offshore oil is worth considering as an adjunct to regulation by a non-industry-controlled agency, but there would be problems in transferring the model to offshore oil and it's not a miracle worker. Two words to make the point that INPO can't do everything: the Davis-Besse nuclear power plant at Oak Harbor, Ohio. In 2002 maintenance work to check nozzles at a difficult-to-reach portion of the reactor pressure vessel at Davis-Besse coincidentally revealed that boric acid corrosion had over the course of years eaten a football-sized hole through more than six inches of steel, leaving less than half an inch of stainless steel to contain the steam pressure inside.
This was an extremely serious lapse in safety by the operator FirstEnergy, despite multiple warnings that boric acid corrosion if neglected could cause a loss of coolant accident. It was coincidence that caught the problem, not INPO or the NRC.
INPO visits have merit because they offer more expertise and more independence than the NRC or most companies have been able to muster, but they can't substitute for what the operator should be doing.
The other limitation of the INPO model when it comes to deepwater oil is the difficulty of cross-inspection by an outside industry team. How would such a team evaluate a new combination of methods, never tried on any rig before? How would they have been able to comment on the maintenance needs of MUX-style blowout preventers versus hydraulic ones, when the former came into use?
Compared to the deepwater oil play, boiling water reactors and pressurized water reactors are a mature technology. In deepwater exploration and production the methods are changing all the time, the operating environment is dynamic rather than controlled, and much of the equipment is inaccessible to inspection.
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