from Robert Wenzel's Economic Policy Journal
By James Stafford
The 2010 Kalamazoo spill and the 2013 Exxon leak in Arkansas are the most glaring incidents, but these are just the big leaks that are found right away and reported.
Most leaks are found eventually—but
there is money to be saved and damage to be avoided by catching them at
the smallest rupture. Right now, we rely on pigs in the pipeline to do
this.
It's called "pigging". Pigs are
inspection gauges that can perform various maintenance operations on a
pipeline—from inspection to cleaning—without stopping the pipeline flow.
The first "pigs" were used strictly for cleaning and they got their
name from the squealing noise they emitted while travelling through the
pipeline. The current generation of "smart pigs" can detect corrosion in
the pipeline and are thus relied on for leak detection.
The Kalamazoo and Arkansas leaks
were massive and caused by complete pipeline ruptures. These are rare
incidents that account for less than 10% of leaks. But the small
leaks--those that traditional pipeline detection systems don't
catch—account for more than 90% of US pipeline leaks.
According to a recent report from
the U.S. Department of Transportation Pipeline and Hazardous Materials
Safety Administration ( PHMSA) ,
the majority of leaks are smaller but can persist for months or even
years, and those that are even reported are generally done so by people
who have stumbled upon them by accident.
The fact remains that current
systems and technologies only detect 50% of leaks. We need new solutions
if we want to avoid another Arkansas, or another Kalamazoo.
The "pigs"
are the darlings of the regulators, who force operators who have had
any problems to "pig" their lines at a massive cost of over $1,000 per
kilometer.
Certainly, today's smart pigs are
well advanced beyond their ancestors—the balls of rags wrapped with
barbwire, but they have their shortcomings.
Pigs can spot general corrosion and
identify potential areas of concern, but they cannot detect pinholes in
pipelines as their spatial resolution is poor and they can only see
corrosion that is 1-2 inches in size. This is significant because a
small leak of 10 barrels per day from a liquid pipeline operated at a
standard pressure would come from a hole much smaller than this.
They are also only deployable over tens of kilometers, not the thousands needed.
Even if all the pipelines in the
world were "pigged" every year, a pipeline operator would still not be
able to ensure that small leaks are being detected.
For the larger pipes, the industry
relies on SCADA. SCADA is a basic infrastructure monitoring system,
where remote hubs relay data back to central monitoring point, using
fiber-optic cable or other communications equipment. But it is not
enough on its own.
A case in point is this: A SCADA system was
working normally on the Pegasus pipeline in Arkansas at the time of the
rupture and helped Exxon verify that an accident had occurred. Pegasus
did not, however, have a Computational Pipeline Monitoring (CPM) program
in place on the pipe. It wasn't enough. Indeed, in late 2012, PHMSA
issued a 17-page warning to Exxon about its insufficient pipeline leak detection.
Then we have Keystone XL, which is
always in the spotlight, most recently when TransCanada said it would
opt out of new pipeline leak detection systems and stick with
traditional methods that many believe are not good enough.
The 90%+ of leaks are small and more
of a concern for the miles and miles of aging pipelines that crisscross
the US, while new pipelines, like Keystone XL will benefit from new
technologies during their construction, such as better pipe metallurgy
and better welding. This will mean less chance of leaks, but not a zero
chance. The fact is that the leak detection systems that will be used by
new pipelines like Keystone XL (assuming it gets the green light), are
not really any better than the current fare.
There is new technology floating around out there—but it's new and relatively untested in the marketplace.
RealSens remote-sensing
pipeline detection technology aims to pick up where SCADA and the pigs
leave off, detecting leaks over an entire pipeline network.
According to Banica,
Synodon's CEO, realSens can actually save companies money by detecting
the leaks sooner and faster and thus reducing the amount of spilled
product and the environmental damage. But it's a new technology that was
only introduced into the market 12 months ago.
Still, some of the big operators
remain skeptical of new pipeline leak detection systems, as their
cost-saving applications are as yet unproven.
"The first hurdle is that operators
might not be aware that it exists and what the capabilities are. The
second hurdle is that they have a hard time believing it works and have
to see proof through customer field tests, which are currently ongoing,"
Banica told Oilprice.com.
But the issue of pipeline leak detection will increasingly be on everyone's radar following the Quebec train disaster that
killed at least 38 people, and counting. No pipeline failure has ever
come close to this level of human carnage. This will help shape the
transport debate.
What the Quebec tragedy
demonstrates, says Banica, is that pipelines are a far better option
than rail. "Whereas pipelines do not kill as many people as rail (or
even truck transport, as more drivers die due to accidents), they do
pose a bigger environmental risk than rail due to larger potential leaks
and releases."
