Nexen spills 5 million litres of oil in Northern AB

[Darkane]

So much misinformation! Must resist.... Just a couple points.

I will say one thing - for those of you who think this is a "pipe blowout" you couldn't be more wrong.

These types of leaks happen as a pinhole on a weld, likely on an elbow UNDER insulation. It will drip, then slowly piss and finally "let go" and it won't be larger than say a toonie or if it's a crack a pencil.

Also, it's not like this is a transportation "pipeline". It's a produced fluid return header from the well pads. It has back pressure from the front end treaters and the wells on the back. You do not notice a drop in production header pressure unless it is a true blow out. Such a blow out will never truly happen on the line as pipe leaks don't work like that - unless you have water/steam hammer which you would not within this line. It's always hot normally when the plant is up.

The DCS may or may not have interlocks for ESD's due to a low production header pressure condition. Most likely just an alarm for the control room to investigate and send a field operator to physically look.

What bugs me is the lack of redundancy in their physical checks. They should have the wellhead field operator doing 2-3 well site and line rounds, the team lead should also do this, followed by maintenance EVERY SHIFT. Obviously they didn't, or didn't look to hard.

[pheoxs]

Originally posted by Freestylin


Yes. There should have been some sort of SCADA system involved, which should either trigger the ESD valve to close at the wellhead or perform some sort of callout to the Operators to have the well shut-in manually at the detection of a pressure drop on the line. It could be possible that the SCADA system was not working at all or the setpoints were not implemented correctly? Maybe the ESD or isolation valves were stuck or leaking and have never been checked?

It also depends what kind of leak we're talking. We do the best we can with the instruments we have but nothing is 100% accurate so if it was a slow leak, you'd never notice unless someone physically spots it.

Sure I can make alarms that will notify them if the flow rate deviates from what is expected, but you always have tolerances on these otherwise you have hundreds/thousands alarms a day and then you miss the important ones.

[Sugarphreak]

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[Redlined_8000]

Originally posted by Sugarphreak


You can have a blow out if you get a slug.

Basically if the heavier material being transported through the settles to the bottom of the line (either because of changes in temp, turbidity, or lack of velocity), it then finds it's way to a low point somewhere along the line. Then this material gets "whipped up" the faster moving commodity passing over it at higher speeds. With enough material it can create a slug, which is a momentary blockage of the line... and with that much pressure behind it, it creates an explosion or blow out.

It is more common on high pressure steam lines, which is why most pipelines have steam traps. However, I don't see why an emulsion line couldn't be the victim of this type of event.


To have a line spew out 8 million liters of emulsion, I can't see how this could be anything less than a total line failure, unless there has been a major leak going on for months... which seems unlikely.

I dont think that slug theory is what happened.

I agree with the pin hole leak.... Gotta remember that once a pin hole is formed it will erode at the metal and the leak will get worse and worse and worse especially with that produced fluid having alot of sand and grits in it. It would not take alot of time at all to go from pin hole to full out line rupture. It might have been blowing out for a good while without anyone noticing it.

[Sugarphreak]

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[DTTB_36]

Calgary Herald title for the latest article says fish mouth leak so it was a good blow out I would bet.

[msommers]

Anyone notice so many animal names associated with O&G? Kind of ironic really

[g-m]

Originally posted by Sugarphreak
Looks like this was an underground pipe

That means it was doubled walled with leak detection. It is connecting to Kinosis, so that also means it is a fairly new line too and not a victim of long term erosion.

The pinhole leak theory works if the detection system had completely failed... but to me it looks like a sudden blow out. I am sticking with the slug.

oh really? Are all underground pipes double walled?

[btimbit]

Originally posted by g-m
oh really? Are all underground pipes double walled?

No, but this one was

[Sugarphreak]

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[msommers]

Sounds like it was 33% oil, and the pipeline was pretty damn new - put in last year.

[dirtsniffer]

Alberta wilderness. AKA industrialized land. as you can see in the photo practically zero natural habitat will be disrupted by this spill / clean up

[msommers]

Wishful thinking lol.

[Seth1968]

Originally posted by Sugarphreak
CBC has a new measurement system for dramatic effect today:

A broken pipeline in Alberta has leaked the equivalent of two Olympic-sized swimming pools of bitumen, water and sand into the Alberta wilderness

Next headline:

If the amount of oil spilled was changed into a gaseous form, it could possibly be enough of an atmospheric air pollutant to kill all living things.

[ZenOps]

I don't know that the CBC measurement is all that bad. People don't know what 5 million litres looks like.

People don't know what a trillion gallons of water looks like either, which is the amount needed to grow almonds in California each year.

Same with 3.4 tons of gold of Canadian reserves, which works out to be 0.1 grams per person.

[Sugarphreak]

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[AndyL]

This is just CNOOC getting around royalties don't pay royalty cleaning up spill - and they'll be cleaning it up all the way to bedrock

Long lake the new open pit cleanup project...

[rage2]

Originally posted by Sugarphreak
They should give a measurement in terms of how many extra-big-gulps it would fill.

3.85 million super big gulps.

[lilmira]

Hippies don't drink big gulp, they have no idea what the heck you are talking about. 165 million shots of espresso, enough for 1000 hippies for like a year.

[Sugarphreak]

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