Porter ranch methane leak
Porter ranch methane leak
(OP)
The Aliso Canyon gas leak:
https://en.wikipedia.org/wiki/Aliso_Canyon_gas_lea...
is a leak in a gas well connected to the sort of underground natural gas storage facility, which now is supposed to represent 1/4 of california's global warming footprint, and is sickening thousands in the nearby neighborhoods, not to mention the freaky infrared pictures of the methane plume
Apparently the self-regulated utility removed a shutoff valve decades ago http://www.laweekly.com/news/what-went-wrong-at-po...
I think environmentally, this will make the VW scam look like peanuts.
https://en.wikipedia.org/wiki/Aliso_Canyon_gas_lea...
is a leak in a gas well connected to the sort of underground natural gas storage facility, which now is supposed to represent 1/4 of california's global warming footprint, and is sickening thousands in the nearby neighborhoods, not to mention the freaky infrared pictures of the methane plume
Apparently the self-regulated utility removed a shutoff valve decades ago http://www.laweekly.com/news/what-went-wrong-at-po...
I think environmentally, this will make the VW scam look like peanuts.





RE: Porter ranch methane leak
http://www.hcn.org/articles/slow-motion-methane-di...
RE: Porter ranch methane leak
Data Point: They're re-opening an old coal mine at Donkin, Cape Breton, NS, Canada. The powers that be have explicitly stated that the 'fugitive emissions' of methane (from the COAL mine) will be equivalent to a million tonnes of CO2 per year. It's not clear which methane-to-CO2 equivalence ratio they're assuming, but it's tens of thousands of tonnes of methane emissions per year. Apparently on-going for as long as they mine coal.
Point being, methane emissions can occur even with COAL.
Hopefully those making the decisions of coal vs natural gas aren't ignoring the methane emissions from mining coal.
RE: Porter ranch methane leak
STF
RE: Porter ranch methane leak
- The gas released is primarily methane with a trace of mercaptan.
- The release rate is 1200 tonne/day (58 MMSCF/day)
- The Clean Air Act explicitly does not allow methane (or CO2 for that matter) to be classed as a pollutant because it is not a pollutant.
- The Santa Barbara seep has been estimated to release 60 MMSCF/day, and the recently discovered seep off the coast of BC and Alaska has been estimated at 600 MMSCF/day. Naturally occurring methane releases (both contemporary biogenic sources and leaking natural reservoirs of fossil methane) have been estmated at 500,000 tonnes/day--this leak is 0.2% of the total
- BTEX at the site of the leak is non-zero, but lower than the average BTEX measured at locations all over the LA Basin.
- No one's health has been adversely affected, and the people who have evacuated claiming a range of health impacts from migranes to cancers are all the same hypochondriacs who crawl out of the woodwork to jump on any bandwagon hoping for their 15 minutes of fame without have to submit to invasive probing by aliens
- From a business perspective, this leak will have a significant impact on the owner's 4th qtr 2015 profit, but will have no impact on the pollution in the LA Basin or the the world's climate.
In short, it is unfortunate that this industrial event has become a focus for hysteria and scare mongering, but it is anything but a "disaster"David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
Dan - Owner
http://www.Hi-TecDesigns.com
RE: Porter ranch methane leak
John R. Baker, P.E.
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Irvine, CA
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RE: Porter ranch methane leak
This has gotten very muddied over the last 4 months and I'm not sure that anyone knows, or that there is just one answer. There were people on TV the night that the leak was discovered saying "they were forced to leave their homes", but listening to those interviews I was never able to tell if they were forced by their own sense of caution or by the government (but it seemed too soon for coordinated government actions). It looks like some time later (again, the early stories are so conflicting that it is hard to put a time on it, the later stories are so coherent that they appear to be professionally stage managed, but foster more hysteria than information transfer) some government agency (don't know if it was state or local) suggested on TV that "anyone concerned for their family's health evacuate", but I am pretty certain that if police or National Guard had gone to their doors to force evacuation those actions would be on the Interwebz and I can't find any video or news stories.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
RE: Porter ranch methane leak
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
RE: Porter ranch methane leak
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
John R. Baker, P.E.
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
RE: Porter ranch methane leak
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
John R. Baker, P.E.
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
RE: Porter ranch methane leak
In 36 years of doing engineering work I have never once used an exclamation point. Not once. I'm kind of proud of that.
I don't know what I said that can be taken as "self-righteous". I was just including an example like I prefer to do to make my points more memorable. And then I was defending that reference against a charge of being disingenuous and un-called for. Sorry if that reference caused you to drag the conversation into the weeds.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
John R. Baker, P.E.
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
RE: Porter ranch methane leak
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
A similar thing happened in Hutchison Kansas many years ago, except they had several building destroyed by fire. And no mercaptans had been added.
The fires were several miles from the leakinging storage facility.
However in Kansas the cause was over pressure of the salt formation.
RE: Porter ranch methane leak
RE: Porter ranch methane leak
My colleagues who live very close aren't worried. One colleague who lives very close thinks it's all hysteria, and hasn't even thought about evacuating even though he has an under-one-year-old baby. He says he's just caught a whiff of the mercaptan a couple of times.
No one has been "forced to leave their homes" in the sense of mandatory evacuation. Yes, many people have thought that it would be prudent to evacuate, and loosely speaking, have felt "forced", but my understanding is that the majority of people in even the closest neighborhoods have stayed.
When I first moved to LA, I was literally across the streets from the La Brea Tar Pits ("the the tar tar pits", my kids liked to joke when they studied Spanish). You could watch the methane bubbling up non-stop there. While I lived there, there was an explosion in a nearby store from methane buildup. Now most (all?) of the buildings around there have prominent methane detectors.
RE: Porter ranch methane leak
Thanks for bringing up "the the tar tar pits" (I had a teacher in 5th grade in Lakewood point it out to us, but I hadn't thought about it in years). I bet the businesses around the pit do have considerably more methane in their buildings than the houses around the "disaster".
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
There's an old joke in LA that "they ruined a perfectly good oil and gas field by building a city on top of it". There are many, many battles around the LA area about emissions from oil and gas drilling for neighbors that don't make national news.
After that methane explosion in the late 1980s, the local congressman, Henry Waxman, pushed through an amendment in Congress that banned the use of federal funds for subway construction in that area, on "safety" grounds. This derailed the planned "Subway to the Sea", and a lot of people thought that the real reason for the ban was that the subway would allow the "wrong kind of people" to get easily from downtown to the affluent communities nearer the ocean. Beverly Hills was particularly opposed.
Now the area is completely gridlocked at rush hours, so there is the political will to extend the subway through this area. I've talked to people in this field, and they tell me that any underground work anywhere in LA must always be vigilant for methane buildups, with constant monitoring and extensive ventilation. They don't see that the Tar Pits area is significantly worse than others. So now my old apartment building is slated to be torn down for a station by the Tar Pits.
RE: Porter ranch methane leak
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RE: Porter ranch methane leak
Thanks for the link. Very interesting! But there's a huge difference between the levels to be able to detect a substance like mercaptan and the levels that could cause harm. The sources I've seen give a 1.6 ppb typical detection threshold, which is very likely far, far below the levels that could cause any harm. The only case of harm I've been able to find was a worker who was dealing with tanks of the "pure" stuff.
I agree with those who think that without the mercaptan, there would probably be no story, even though it's a tiny, tiny component of the leak. It is ironic that the whole point of adding the mercaptan is to annoy the hell out of people, but that's really for fire safety purposes.
RE: Porter ranch methane leak
TTFN
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RE: Porter ranch methane leak
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RE: Porter ranch methane leak
Keith Cress
kcress - http://www.flaminsystems.com
RE: Porter ranch methane leak
http://www.huffingtonpost.com/entry/california-nat...
John R. Baker, P.E.
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Irvine, CA
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RE: Porter ranch methane leak
• one inch in 16 miles,
• one second in 11.5 days,
• one minute in two years, or
• one car in bumper-to-bumper traffic from Cleveland to San Francisco.
The major fate of atmospheric methyl mercaptan is photooxidation. The estimated atmospheric lifetime is only 1.2 hours.
The daily California smog has more effect than the mercaptan.
RE: Porter ranch methane leak
TTFN
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RE: Porter ranch methane leak
http://www.arb.ca.gov/research/aliso_canyon/commun...
http://oehha.ca.gov/public_info/emergency/alisocan...
Regarding "Mercaptan is heavier than air, so children who are closer to the ground would be more susceptible."
That is a stretch.
RE: Porter ranch methane leak
http://www.porterranchlawsuit.com/wp-content/uploa...
Porter Ranch is in an area that can often get high winds, so open areas are likely to get swept clear of gas, otherwise, people would be dropping like flies. Nevertheless, enclosed or walled areas might not get swept, and might accumulate mercaptan in higher concentrations. Even the guy from AQMD on NPR this morning seemed somewhat unclear about the fact that methane is odorless, and should have be referring to the mercaptan. But mercaptan is simply mixed with the methane, so there's no mechanism for keeping them together. You could blow away all the methane yet still retain the mercaptan, since it's heavier than the methane.
"That is a stretch."
Why is that a stretch? That was directly from the CDC.
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RE: Porter ranch methane leak
RE: Porter ranch methane leak
How is that the case, given that both your link and mine show measurements of higher than background concentrations in the middle of neighborhoods, and these are only spot checks? Even your citation of 230 ppm, which was measured on Nov 11, was measured in the vicinity of the cul-de-sac on Turtle Springs Ct, where there were at least 9 houses within 100 ft of that measurement.
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RE: Porter ranch methane leak
RE: Porter ranch methane leak
RE: Porter ranch methane leak
I don't think your units are right. The injected number is in the ppb range, not ppm. My experience agrees with yours. With widely differing gas densities it is a real chore to get them to break back up, and you get no measurable gravity separation of gases.
bimr,
Thanks for the time series data on concentrations, I've seen some of it, but not that much.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
Sorry for the digression.
A.
RE: Porter ranch methane leak
I've seen samples taken at the top, middle, and bottom of very tall towers that were shut in and the mix of gases was the same in each location as the other locations.
Gases do not gravity separate. We get the idea that they will because if the combined mix of gases (say, you've mixed hydrogen and helium with propane until the blended specific gravity is greater than 1.0) then the mix will settle and you can get hydrogen and helium in a sample taken at ground level. Over time the mixture will blend with air until our three added gases can no longer be found, but as long as there is a substantial portion of the propane the mix will stay close to the ground.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
I read the odorant laws for 5 states, the ISO, and 4 countries and they were all about the same. Several industry documents had much the same data. All say that the threshold for reliable detection is 10 ppbv (it has a scent at 1 ppb, but less than half of the population can pick it out). They all say that there should be enough odorant in the natural gas to detect it at 1/5 of LEL (generally taken as 1/5 of 5% or a methane concentration of 10,000 ppmv. That is where all the laws and industry guidance stop.
To have at least 10 ppb in a mixture that is 99% air and 1% natural gas, it seems to me that the natural gas must have had a concentration of 1% odorant. That seemed like a lot, but I've approached it from a couple of different directions and got the same answer. Does that number seem right to anyone else? The permissible exposure limit is 10 ppmv for "methyl mercaptan" (there really isn't any product by that name still on the market, but the name persists).
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
In terms of my mixing question, I think what you're telling me is that unmixed volumes of heavy vapour tend to sink before they inevitably mix with everything else; that, once mixed, they stay mixed (in the mixed state, the heavier components no longer sink relative to the others) and that it is the difference between these two behaviours which is counterintuitive enough to the lay observer to make it worth pointing out. Makes sense - just never had to worry about it before. Thanks.
A.
RE: Porter ranch methane leak
Common mercaptan doses are in the range of 2 – 4 ppm (by volume, to gas).
RE: Porter ranch methane leak
Take for example salt and water. Salt is denser than water and will sink rapidly. It can sit in the bottom of a glass for hours or days but eventually it will completely dissolve and be at a uniform concentration throughout the glass. What drives the mixing is molecular diffusion, which also causes Brownian motion (think marbles bouncing around in a box).
Salt water can form a fairly stable layer under a layer of fresh water. But eventually the layers will mix. Once mixed, salt never separates from water due to gravity. In gasses the rate of diffusion is orders of magnitude greater than in liquids.
RE: Porter ranch methane leak
http://highline.huffingtonpost.com/articles/en/ame...
John R. Baker, P.E.
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
RE: Porter ranch methane leak
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
John R. Baker, P.E.
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
RE: Porter ranch methane leak
I've been poor. I've lived in very poor communities. I've never found "poor" an adequate excuse for "slovenly". The problem in New Orleans (where there are still neighborhoods that still have more condemned houses than occupied houses) was an "entitlement" mindset that has pervaded the community. There are some great people who call New Orleans home, many of them are quite poor, none of those folks saw FEMA as a long-term solution and had arranged for alternate accommodations within a few months of Katrina. There were too many people of every race that just changed their address for their welfare checks to the FEMA trailer.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
RE: Porter ranch methane leak
I made an offhand comment that the people who chose to leave their homes (there really wasn't any "forcing) were similar to the people who continued to live in FEMA trailers for years after Katrina. Mr. Baker took very strong offence and claimed that I was denigrating the noble inhabitants of New Orleans who had no choice by to live on the dole for a decade. I thought that conversation was over until the Mr. Baker posted the picture this morning. I am not wired to let something like that stand. I should have been the bigger person and just ignored it, but I've seen what other Gulf Coast communities did after the storm and find it amazingly offensive to attribute any nobility to New Orleans.
A post above from cswilson indicated that his office is in the area and many of his co-workers stayed in their homes through all of this "disaster". The implication I made was that the "thousands" of displaced families are the moral equivalent of the citizens of New Orleans living in FEMA trailers for years, except those "FEMA Trailers" are hotels located closer to their workplaces than their actual homes are.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
Possibly so. John isn't the only one who took exception to your assessment. You're only making it worse with every post, as well. Please move on.
RE: Porter ranch methane leak
I do not know ZDAS04 or anything about him, but I know ZDAS04 is only communicating with best intentions what he knows in his heart is the solution to adversity. He is communicating that hard work, perseverance in the face of adversity is what allows us to succeed everyday. We, as a self-selected group of engineers participating in an engineering forum, all embrace these tactics every single day in our engineering duties. If your are an engineer with any experience you have been kicked when down, failed, laughed at probably behind your back, and had to make do with scarce or non-existent resources. But we keep coming back, we fight, we persevere through our mistakes and ultimately we succeed. Many of us also apply these lessons to our life outside of work. We hold ourselves to this standard so why cannot we hold others to this standard? Do we think others are inferior and not capable of commitment, perseverance, and hard work? I would question those with their immediate negative outlook on ZDAS04 what their true feelings really are. He knows what would work for him, get out clean up the trash, bucket out the water, and find a way to make it work...one 2x4 at a time. No one is coming to help you and it is up to you. When you make a mistake, have a construction company calling telling you that you are holding up a $100K a day operation does anyone bring dinner and make sure the coffee is still on at 1:00 AM? No, you stick it out most often because by that time all the project champion cheerleaders are long gone and now it is your fault the company is loosing money and your neck is on the line.
You can say that a small example is not as great as loosing your home, however, the philosophy and answer is the same. We succeed through self-reliance, it does not mean we have not been helped or exist in a vacuum, but when things get rough it comes down to you.
We of all groups, the engineers, the problem solvers of the world know what it takes to get things done and succeed. To not communicate and share this knowledge of how we operate would be a failure. We hold ourselves to these standards, why should we not hold others to this standard? View it from the constructive side, if everyone had the resolve and perseverance the country would be a better place. There are countless examples of this at work all over the country; towns flood, tornadoes come through, peoples homes burn down, businesses burn. It is the reaction to these occurrences which determine the final outcome.
Instead of looking at it as negative, please view it as constructive, he is sharing what he knows works and wishes others could perceive there problems in the same light. It has worked for us, why cannot it work for others?
RE: Porter ranch methane leak
Latest news and commentary:
Political commentary is interesting yet:
This article has a pretty good context for where 'The Porter Ranch Leak' falls in the scheme of methane released into the atmosphere, which many have touched on, already, in this thread:
and then it turns into a sales pitch for biogas. I'm not criticizing biogas - I'm rather ignorant of the hard facts about it on a macro scale.
The frustrating reality of most legislation persists across all sectors... react to the popular problem, not the most effective problem.
RE: Porter ranch methane leak
The first quote was pretty consistent with most of the reporting on this leak. The references to "spewing", "disaster", and "save our community" have filled the media for months.
The second quote was quite useful and brings some information that has not been readily available. The "evil corporation" rhetoric that has been so common has been toned down to "we tried to adjust our rate base to be able to afford to address our aging infrastructure, but were denied". Much the same comments as [finally] came out months after the San Bruno explosion and the Plains All American Pipeline oil leak into the ocean last summer.
The third quote was a touch premature. At natural gas prices less than $2/MSCF, developing widespread biogenic methane harvesting would be very much like our current wide-spread wind power exercise--we keep dumping federal and state money into companies that have no intention of deploying a competent product. The biogenic methane harvesting effort is developing in the private sector and the rate of evolution is staggering. A number of cities are harvesting land-fill gas to run turbines for power generation quite successfully (and there are conferences where municipalities share best practices). A large number of cities are looking at or have started processes to configure new land fills to better facilitate harvesting methane with an eye towards generating power in the future. It is very common in feed lots, pig farms, and dairy farms to take the animal waste to anaerobic digesters and using the waste heat to heat barns and greenhouses while extracting the methane to generate electricity and the sterilized waste as a soil supplement. Hundreds of fantastic examples of great engineering. I am really scared that once it gets on EPA's radar we'll see federal dollars flowing into the field in magnitudes that attract the hucksters. Low natural gas prices are slowing the government-ization of this field (it makes sense to process waste to avoid paying for power as long as you can use the waste heat and sterilized waste productively, but processing waste for the natural gas grid puts you in the position of spending $6/MSCF to sell it for $2/MSCF).
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
TTFN
I can do absolutely anything. I'm an expert!
homework forum: //www.engineering.com/AskForum/aff/32.aspx
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers
RE: Porter ranch methane leak
Your house vent is pretty common.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Porter ranch methane leak
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Porter ranch methane leak
TTFN
I can do absolutely anything. I'm an expert!
homework forum: //www.engineering.com/AskForum/aff/32.aspx
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers
RE: Porter ranch methane leak
On the other hand, street lights can be of several different colors, or sizes (light output or shape), where gas lights seem to have a limit on the shapes.
RE: Porter ranch methane leak
http://www.pddnet.com/news/2016/04/california-face...
RE: Porter ranch methane leak
RE: Porter ranch methane leak
The problem is not the facts, or lack of facts provided. It's that some people live on feelings and don't care about facts.
Sort of like NIMBY, and bury all the power lines. Facts don't matter.
For a parallel look at the fires a number of years ago, in Hutchinson Kansas.
RE: Porter ranch methane leak
http://www.huffingtonpost.com/entry/pge-fine-gas-e...
Anyway, it looks like PG&E dodged a big bullet...
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
RE: Porter ranch methane leak
There is a closed thread on this topic in thread378-281116: San Bruno 30" Natural Gas Transmission Line, -FAIL-
B.E.
You are judged not by what you know, but by what you can do.
RE: Porter ranch methane leak
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without