Alaska Oil Pipeline
Extreme Environments
Syllabus Ref
• Mineral extraction.
Periglacial areas: examine the opportunities and
challenges posed by permafrost and other
characteristics of periglacial areas for resource
development (mineral extraction and any
associated settlement and communications).
Challenges and Opportunities
• To build the pipeline in such extreme
conditions, several challenges had to be
• On your handout match the problem to the
Problem - Permafrost
• The oil must be heated in order to flow
through the pipeline. It is 32 degrees when it
reaches Valdez. Heat from the oil must not
melt the permafrost, otherwise the ground
will become boggy and could crack the pipe.
Solution 1 permafrost
• The pipeline above the
permafrost is raised
above ground and a
layer of gravel and
insulation is placed
beneath it to insulate
the ground and prevent
the permafrost from
Problem - Expansion & Contraction
• Alaska is cold in winter, but warm in summer.
This and the heated oil, causes the pipeline to
expand and contract and risk breaking
Solution – expansion & contraction
• To allow for expansion
and contraction, the
pipe does not always
travel in a straight line
and instead zigzags to
allow for sideways
movement of the pipe.
Problem – Tundra Environment
• There are many sensitive species of lichen and
plants which can be easily damaged by
vehicles. North of the Brooks Range there are
treeless plains which are particularly
• There is a gravel road
built alongside the
pipeline, which vehicles
must use to try to
protect the surrounding
4. Mountains
• Alaska is mountainous!
• The Alaska range crosses the state
Mountains - solution
• There are 12 pump
stations along the
pipeline to pump the oil
up the mountains.
• The pipeline route crosses 34 rivers and over
800 streams
Rivers - solution
• Across the largest river,
the Yukon, a bridge has
been built to carry the
road and the pipeline.
Across the smaller
rivers and streams the
pipeline is laid across
them rather than
• Valdez and southern Alaska are in an
earthquake zone
Earthquakes - solution
• The oil tanks at Valdez
are designed to
withstand major
earthquakes up to 8.5
on the Richter scale.
Theyare sited high
above sea level so are
not at risk from tsunami
• Caribou migration routes cross the pipeline.
Caribou do not like the man made pipeline
Wildlife - solution
• Animals can move
under the pipeline.
Where migration routes
cross, the pipeline is
buried underground
and insulated.
Exam qu
• Examine the challenges presented in
periglacial areas for mineral extraction.
• 10 marks
• You should include detail about the nature of
the environment (ie it is extreme)
• Clearly link the extreme conditions to
• You should discuss oil extraction at Prudhoe
Bay and the associated pipeline, transport
routes, settlement at Deadhorse and Valdez