Comment by mkaufmann | Hacker News Reader

Comment by mkaufmann | Hacker News Reader

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On the topic of what went wrong I think this LA weekly[3] article is a much better source. The main problem why the well can't be shut down is that the security valve was removed about 40 years ago: "He pointed out that the valve was old at that time and leaking. It also was not easy to find a new part, so the company opted not to replace it.". Certainly a bad decision and it should be checked if regulations need to be changed to avoid similar problems in the future.

EDIT: The old version had used the wrong conversion factors, now corrected

The central number is the exhaust mass of 110,000 pounds per hour. So how much is this really? This is about 50 metric tons of methane per hour. To be able to compare it with other greenhouse emissions we can calculate the CO2 equivalent by multiplying with 0.01133[1] giving the rate of: 1247 metric tons CO2e per hour.

Using the EPA Online tool[2] we can relate this to the toal emissions in Calfornia or the US. The total emission of methan measured in CO2e for California in 2014 was: 9,546,270 metric tons CO2e. Converted to a rate per hour this gives: 1089 metric tons CO2e per hour.

So while the well is leaking it is releasing 114% of the normal methane emissions of California.

Compared to all greenhouse gas emissions the well is causing an increase of 10% in california and 0.3%at the US national level compared to the emissions from large facilities.

[1] http://www3.epa.gov/gasstar/tools/calculations.html

[2] http://ghgdata.epa.gov/ghgp/main.do

[3] http://www.laweekly.com/news/what-went-wrong-at-porter-ranch...

> we can calculate the CO2 equivalent by multiplying with 3.6

3.6x is how much CO2 is produced by burning methane (i.e. converting CH4 + 2 O2 => CO2 + 2 H2O).

Methane released into the atmosphere is 25x more potent as a greenhouse gas compared to CO2. See Global Warming Potential of methane in your [1] link.

So 50 metric tons of methane per hour is equivalent to to 1,250 tons of CO2e.

There's probably a really obvious answer to this really stupid question, but why don't they light the leak on fire until they stop it?

From what I understand, the gas is not flowing out of a pipe at ground level; the leak is deep underground and it is diffusing into rock and coming up over a wide area. It's not clear that combustion could be sustained in that configuration. I have as much oil/gas industry experience as rube goldberg, but I suppose if they put a huge upside-down funnel over the area maybe they could collect it and light the top, but I have no idea whether the radius of that funnel would have to be 10m or 10km.

I feel a good solution would be to implement a carbon tax, and an unburnt methane tax at the greenhouse equivalent, and start charging the company the estimated leak. I imagine their engineers would become more motivated.

This video shows the gas coming right out of the pipe:

http://arstechnica.com/science/2015/12/infrared-video-of-hug...

http://www.laweekly.com/news/what-went-wrong-at-porter-ranch... has a very clear diagram of what's happening. The inner casing of the well sprang a leak. The gas is blowing all the way back down the outer casing of the well, then exiting adjacent to the casing. So, while the leak is concentrated to an area directly adjacent to the well, it's not a matter of simply capping the pipe.

If you argue that the motivation of the engineers is at all an issue, I invite you to present yourself on the south field at dawn. Bring your second.

perhaps more acurately, it would motivate the budget holders... engineers work with the resources their company allocates. a large tax/fine would certainly help incentivise the right kind of response. although, the fine should be large enough to have prompted the correct behaviour in 1979!

That's how the Door to Hell[1] was made.

1: https://en.wikipedia.org/wiki/Door_to_Hell

I corrected the analysis, thanks for the clue, this paints a completely different picture. I corrected the analysis

But the atmospheric residence time of methane is short - a decade or something. Nothing to worry about in the grand scheme of things, once the leak is plugged.

The factor of 25 accounts for this - over a 100-year timespan, methane is 25x worse than the equivalent weight of CO2.

Over a shorter 20-year timespan, it is 86x worse.

https://en.wikipedia.org/wiki/Global-warming_potential#Value...

You're right, the LA Weekly article is superior. Its author has been reporting around LA for a long time.

Porter Ranch is an interesting place for this to happen. It is a cluster of gated communities with $1M+ homes. People generally move there to be left alone, and watch their property values increase -- this gas leak is deflating both of those dreams.

Sounds like a great time to buy one of these homes.

The figure used for converting metric tons CH4 to metric tons CO2e seems quite low, and I'm not sure what exactly it means in the context of the chart you cite. Indeed, if you plug "110,000" into the calculator [1] references you get 1,247 metric tons CO2e as a result.

That calculator uses a figure of 22.7 for conversion from metric tons CH4 to metric tons CO2e. Many other sources use the number 25.

25 is the correct number.

22.7 is used to convert short tons CH4 to metric tons CO2e. (A "short ton" is what we call a "ton" in the US)

Right. I still wasn't looking closely enough.

I corrected my calculation (using the correct 25 factor for metric tons). Thanks for the hint!

Ok, we changed the URL from http://motherboard.vice.com/read/why-we-cant-stop-the-enormo... to the more substantive LA Weekly article. Thanks.

I grew up in Southern California and the tone of the LA Weekly Article reflects the reputation of The Gas Company as we knew it, conservative, safety oriented, safe.

I guess a culture built around nothing going wrong doesn't always respond well when something does.

Another perspective, this accounts for 0.17 % of US total GHG emissions (for all sources excluding land use change and forestry; source: World Resources Institute, for 2010). One might argue that means it's "small" or insignificant, but I'm going to argue that the lesson should be how staggeringly large our emissions are. Change needed, and soon!

Thank you for the coherent and quantitative analysis. The original article is an example of the rampant & incoherent innumeracy that dominates reporting on quantitative issues.

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