From the U.S. Government Accountability Office, www.gao.gov

Transcript for: U.S. Energy Gas Pipeline Safety

Description: The U.S. energy pipeline network is composed of over 2.7
million miles of pipelines transporting gas and hazardous liquids. What
are these pipelines made of and how are they maintained?

Related GAO Work: GAO-17-639: Pipeline Safety: Additional Actions Could
Improve Federal Use of Data on Pipeline Materials and Corrosion

Released: August 2017

[ Background Music ]

[ Susan Fleming: ] Pipelines are a relatively safe mode of transporting
dangerous materials. However, things can happen.

[ Sarah Kaczmarek: ] Welcome to GAO's Watchdog Report, your source for
news and information from the U.S. Government Accountability Office. I'm
Sarah Kaczmarek. The U.S. Energy Pipeline network is composed of more
than 2.7 million miles of pipelines, transporting gas and hazardous
liquids. Pipelines are a relatively safe mode of transportation, but
incidents caused by material failures and corrosion may result in
fatalities and environmental damage. A team led by Susan Fleming, a
director in our Physical Infrastructure team, recently looked into gas
pipeline materials and corrosion. So I asked her, what are these
pipelines typically made of?

[ Susan Fleming: ] The vast majority, about 95 percent of pipelines, are
constructed of either steel and plastic with some minor use of other
materials such as composites and iron. But the extent of steel and
plastic in our network really varies. The pipelines that gather natural
gas or hazardous liquid materials from production wells and transport
these materials to processing facilities. Nearly all of these pipeline
systems are made of steel. Transmission pipelines transport gas and
natural liquids sometimes over hundreds of miles at very high operating
pressures to communities and large volume users such as facilities.
Proposed Dakota Access or Keystone pipeline would be an example of a
transmission line. And those are also primarily made of steel. Lastly,
distribution pipelines which really transmit natural gas to homes and
businesses, there's been kind of shift away from steel to plastic and
about half of all of those lines are made of plastic currently.

[ Sarah Kaczmarek: ] So my house actually backs up to a large gas
pipeline and I, and I'm sure many other homeowners worry about leaks. So
how do you go about preventing corrosion in these pipelines?

[ Susan Fleming: ] Our report focused on the technologies that pipeline
operators use to prevent corrosion in pipelines. And along with material
and weld failures, they do account for about a third of all significant
incidents with pipelines. Operators use primarily two technologies to
try to protect steel from corrosion. The first is on the surface of the
actual pipeline. Operators apply a coating which is a protective layer
of plastic material or other chemical compound and it's applied and
bonded across the surface of the pipeline. Second, to supplement these
coatings pipeline operators then have to use cathodic protection which
applies an electric current in the pipe and it prevents the chemical
reaction that causes corrosion.

[ Sarah Kaczmarek: ] So, how does the federal government go about
overseeing the safety of pipelines that it regulates?

[ Susan Fleming: ] PHMSA which is in -- within the U.S. Department of
Transportation works hand in hand with state pipeline safety offices to
oversee and inspect federally regulated pipelines. As you can imagine,
PHMSA basically is responsible for transmission pipelines which cross
state boundaries while states are primarily responsible for intrastate
pipelines which are those gathering and distribution lines. And PHMSA
basically uses a model to try to determine how frequently to inspect
particular segments. We basically looked at that approach and we found
that PHMSA uses its own professional judgment but didn't really document
key decisions and also didn't take that necessary step to determine
whether or not it's overall approach is effective and prioritizing the
right segments for inspection.

[ Background Music ]

[ Sarah Kaczmarek: ] Given the challenges of ensuring pipeline safety, I
wondered how the government uses its limited inspection resources
effectively. I asked Susan to talk about some of the recommendations her
team made in this report.

[ Susan Fleming: ] Ultimately we recommended that PHMSA take two steps.
First, it document those decisions and assumptions in the model that
were used to really determine whether or not the right factors and the
right weights were assigned. And also to take that step back and to
really look at whether or not their overall approach and effect and
model is really effective in prioritizing inspections.

[ Sarah Kaczmarek: ] So finally, what do you see as the bottom line of
this report?

[ Susan Fleming: ] You know pipelines -- I think it's important to note
that pipelines are a relatively safe mode of transporting dangerous
materials. However, things can happen. There are risks imposed just by
the fact that they are in your neighborhood. They're in facilities.
They're in communities. And I think it's really important that PHMSA
really assess the threat that these systems can pose and really take a
step back and think about its overall approach and to make sure that
it's managing those limited resources effectively and maximizing safety
benefits to the public.

[ Sarah Kaczmarek: ] Thanks for listening to the Watchdog Report. To
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