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The single most common cause of pipeline failure is
mechanical damage from third-party contractors encroaching on pipeline
rights-of-way. According to the US-based Pipeline Research Council International,
this is certainly the case in America – “and this picture is
repeated in many other countries throughout the world.”
To illustrate the nature and extent of this problem,
consider a recent natural-gas pipeline explosion outside a town in northern
Texas. It killed one person, injured several others and sent flames high into
the air. The dead and injured were employees of a contractor replacing
power-line poles when they hit the pipeline. These victims didn’t even
know they were working in a pipeline right-of-way.
To actively prevent this kind of pipeline damage,
operators have to look high – a lot higher, according to Moness Rizkalla. Increasingly,
he says, pipeline companies should be looking to the dozen or so radar
satellites among the roughly 13,000 space vehicles now circling the earth.
A long-time pipeline integrity specialist, Rizkalla is president of Visitless
Integrity Assessment (VIA). So far, his clients have included El Paso
Corporation, Sempra Energy, General Electric, the Virginia Utility Protection
Service and Alliance Pipeline. VIA uses satellites to track areas of pipeline
risk, Reflecting levels of increasing urgency, the company gives its
customers “notices, alerts and alarms” if their lines are in
peril because of men and machines.
“When damage is caused by (this kind of)
third-party encroachment,” Rizkalla
deadpanned, “it isn’t the operator’s fault but it sure is
the operator’s problem.” He reached for his notes.
“Seventy-five per cent of online pipeline ruptures are caused by third
parties, and 90% of those failures occur immediately upon contact with the
line. And about 70% of those incidents involve unauthorized encroachment
taking place without any contact being made with the local one-call
organizations. Sixty-five per cent occur on pipelines where signage
exists.”
The Costs
The costs of third-party damage can be immense.
Apart from fatalities and injuries to workers, there are other public safety
implications. Canada’s single worst episode – it occurred in 1979
– illustrates the safety issue well. A heavy-equipment operator
ruptured a major propane pipeline. The product exploded, nearly killing the
worker, who suffered third-degree burns over most of his body. In what was
then Canada’s biggest-ever peacetime evacuation, more than 19,000
people were ordered from the suburban Edmonton neighbourhood
– Millwoods by name – where the
disaster occurred.
The non-safety issues can also be huge. Rizkalla ticked them off on the fingers of one hand: The
cost of repairing damage so you can resume pipeline service can be huge. If
the product ignites “there could be an ignition dimension,” which
can lead to property and environmental damage. Lost product – usually
small amounts, but sometimes large – means lost income and the time and
expense of recovery. Delayed delivery could lead to contractual problems and
possible lawsuits. Then there are the corporate image and public relations
impacts, which can take the form of lower stock prices and penalties from
regulators.
Three decades on, it is obvious that Alberta
ultimately benefited from the Millwoods calamity.
In response a consortium of municipalities, utilities and private sector
companies created the Alberta One-call Corporation. Best known for the
tagline “Call before you dig,” the corporation now receives
around 400,000 calls per year asking for utility locations from individual
homeowners, contractors and corporations wanting the safety, savings and
convenience of a less complicated operation.
One-call and utility companies try to prevent all
potential problems. Alliance Pipeline, for example, asks people to call
before they do deep ploughing; install drain tiles;
construct fences or driveways; or even plant a tree.
One-call systems are an excellent first line of defense,
but they represent passive prevention. As long as people wanting to dig make
the call, public safety is the winner, and companies don’t have to be
proactive. The drawback to this model, of course, is that right-of-way
infringement still exists, so there is a need for operators to actively
pursue pipeline integrity.
High Technology
A fervent advocate of pipeline monitoring (“a
step improvement to traditional company monitoring”), Rizkalla described the system as “a peerless
form” of active prevention. A pilot study by the Virginia Utility
Protection Service confirmed that satellite-based monitoring can contribute
significantly to pipeline protection within a jurisdiction that already has a
one-call service.
Relative to the communities where we live, even
low-orbit satellites are about the highest technology to have a major impact
on our daily lives. By buying services from Canada’s two low-orbit Radarsat satellites, VIA uses right-of-way snooping to
guard against damage from third-party encroachment. The satellites are owned
and operated MacDonald Dettwiler, an aerospace
company based in Richmond, B.C.
Other countries have developed similar SAR
(synthetic aperture radar) technology – notably Italy, an Anglo-German
consortium and Japan – but “Canadians should be very proud that
we are a world leader in it.” These systems are not for communications
but for earth observation. They are like good cameras in the sky – but,
because they are based on radar, cameras that are effective despite cloud,
fog and smog.
The VIA system is based on satellite images of
contracted sections of pipeline right-of-way. Properly analysed,
Radarsat images can reveal whether the right-of-way
contains vehicles that are not supposed to be there. By identifying big hunks
of metal – generally heavy construction equipment, including pickup
trucks, backhoes and bobcats – that have suddenly appeared on a
client’s right-of-way, VIA can establish that mechanized activity is
taking place, and by comparing images, create a simple record of what took
place over what period of time.
“From the satellite you can accumulate a
series of images of what’s been going on there. And then, through
computerized change detection software, you can work out the history,”
according to Rizkalla.”If you subtract one
image from the other, you can identify a target – something metallic
which is simply not supposed to be there. Moreover, you can detect the
precise location of the target. You can do all of this from GIS
layers.”
“The operator knows where the risks
are,” he added, “and they go out and check. Sometimes it ends up to be a false alarm. However, false alarms are less than
10%. Detection accuracy is greater than 80%, and we can prepare reports
within three hours of image acquisition. It’s a near-real-time
detection scenario.” As part of the process, pipeline integrity wonks
compare identified encroachment incidents with service tickets that have been
issued by the area’s one-call service. Those that can’t be
unaccounted for are the subject of immediate investigation.
Potentially, satellite monitoring provides a
valuable contribution to the risk management toolbox. “The big pipeline
operators are becoming very sophisticated at risk management, and this is a
risk mitigation technology which needs to be deployed in high-risk
areas,” according to Rizkalla. “One of
the areas that we (as a business) are finding to be particularly high-value
is in the outskirts of big cities where there is a great deal of construction
activity going on – where there are known areas of major
development.” Prices go up with greater surveillance, but the more
satellites you use the more detailed the coverage you get.
Geohazards
While VIA’s main focus is to help reduce risk
from third-party intrusion, the company has also identified the mitigation of
geohazard risk as a business opportunity. In this
case, geohazard refers to ground movement as subtle
as the shift of soil from winter-freeze-up. Over time, these movements can
cause damage to underground pipe and even surface equipment.
The word “geohazard”
normally refers to phenomena in the physical environment such as earthquakes,
landslides, floods or volcanic eruption that can occur naturally and can
threaten artificial structures. In the context of pipelines, however, the
term refers to a wide range of environmental loads and effects, some of which
are actually triggered by pipeline installation or operations. Some 35 years
ago, an Alaska Pipeline task force defined geohazards
as “natural hazards of a geotechnical, geological, hydrological, or
tectonic origin that represent potential threats to the pipeline,
right-of-way and/or ditch, including hazards induced by pipeline installation
and/or operation.”
You can often anticipate emerging geohazards through ground movement monitoring, and VIA
says satellite tracking can sometimes be a viable competitor. To monitor
ground stability, you need to tag key pieces of equipment with markers or
transponders that the satellite can identify. As the satellite passes over
the area, every 15 to 30 days it takes images of the markers. Automated
systems then compare the target images for ground stability.
However, the use of slope indicators for geohazard measurement has “been around for many,
many years,” according to Rizkalla, so doing
the same thing by satellite “really is a price
play.” The use of satellites to measure ground stability can be
cost-effective for operators, but mostly in areas like Swan Hills, the Peace
country and the Fort McMurray region, where they can monitor many pieces of
pipe and equipment with a single flyover. “The more innovative product,
which I believe is going to be a step-change worldwide, is the monitoring of
third-party encroachment. Protection against third-party encroachment is the
real innovation we are taking to market.”
Peter McKenzie-Brown
Language Instinct
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