This is incredible.
New info in the Salem, Westmoreland Co., PA failure of the TETCO (Spectra).
in 2012. An inline inspection found 30% wall loss!! New info in the Salem, Westmoreland Co., PA failure of the TETCO (Spectra).
And Spectra took no action.
Four years later it failed, scarred a man for life, destroyed his home,
http://www.alleghenyfront.org/pipeline-inspectors-saw-corrosion-on-texas-eastern-back-in-2012/
Spectra says, essentially, it failed sooner then we expected.
Andy Drake, vice president of operations for the Houston-based company, says the corrosion was revealed during a 2012 inline-pipeline inspection. It showed a 30 percent decrease in the thickness of the pipeline's wall.
"It was very small. It was smaller than any threshold we would have been required to [take] action on or investigate," Drake says. "The anomaly grew at a significantly higher rate than anything we've seen in the past."
Spectra says, essentially, it failed sooner then we expected.
Wow. 30% wall loss seems like significant corrosion to me.
Why did Spectra do nothing?
The Spectra rep quoted in this article indicates they have prioritized all of their anomalies, and concluded a spot of 30% loss in a Class-1 area, doesn't make the cut in 4 years.
This makes perfect sense from a cost-benefit equation,
but is astounding from a pipeline safety perspective.
but is astounding from a pipeline safety perspective.
Line 27 was installed in 1981.
So even if we assume linear rate of corrosion,
then we have about 1% wall loss per year.
30% in 30 years.
The Spectra guy is saying is they took no action
(essentially) because 1% corrosion per
year is nominal, 30% loss is not an action threshold
(at least not in Class-1), and they have worse problems
in the field.
Sweet baby Jesus.
So he is implying, something site-specific happened since 2012
which increased the rate of corrosion FASTER than 1% per year,
which is what they expected.
My head is swimming contemplating this question:
If 1% per year is considered nominal wall loss
even with best technology in 1981 inc. CP,
and a spot of 30% loss is non-actionable... wow.
even with best technology in 1981 inc. CP,
and a spot of 30% loss is non-actionable... wow.
What does this imply about the shape of our national pipeline system?
IMO-- PIPELINE OPERATORS should prioritize the following sites- 1) wet areas (e.g., creekbeds)
- 2) within 5 miles downstream of a compressor
- 3) nearby sources of stray DC, such as CP systems from foreign pipelines (at crossings and/or co-located ROWs), bridges, railroads, storage tanks, or other sites where CP is used.
See:
http://www.desmogblog.com/2015/04/30/exclusive-transcanada-keystone-1-pipeline-suffered-major-corrosion-only-two-years-operation-95-worn-one-section
http://www.desmogblog.com/2015/07/28/evidence-released-transcanada-s-keystone-xl-permit-renewal-hearing-sheds-light-serious-pipeline-risks
BH
--
--
May you, and all beings
be happy and free from suffering :)
-- ancient Buddhist Prayer (Metta)
May you, and all beings
be happy and free from suffering :)
-- ancient Buddhist Prayer (Metta)
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