Hydraulic fracturing, or fracking, is used to increase the flow of oil or natural gas from a well. It has been used safely around the world since 1949 in over two and a half million wells. Santos has used fracking to produce oil and gas in South Australia and Queensland for nearly 50 years. It has also been used in other industries to increase the flow of water wells or to clean up hazardous waste sites4. In over 60 years of operations, there has not been one proven case of water contamination as a result of fracking. Studies in the United States, United Kingdom and here in Australia have concluded that fracking can be undertaken safely.

1. Find out more about...
Hydraulic fracturing (fracking)
Did you know?
Both state and federal
government in Australia strictly
regulate fracking and fracking fluid.
Fracking has been used
in Australia for over 50 years
without incident.
Fracking fluid contains 99 per cent
water and sand and only small
quantities of common chemicals1
.
Fracking was first used
commercially in the U.S. in 1949.
Fracking is a proven and accepted
technology used worldwide to make
oil and gas wells more productive.
A U.S. EPA report on fracking
concluded that it “poses little
or no threat to underground
sources of drinking water”2
.
+ Hydraulic fracturing is a proven technology
used globally for over 60 years.

2. Santos Sustainability Report 201322
Understanding
hydraulic fracturing
Hydraulic fracturing has been used since 1947 to enhance the
permeability of hydrocarbon reservoirs. We have used fracture
technology in the Cooper Basin for nearly 50 years without incident.
Wells are constructed to best industry practice, lined
with steel casing and cemented in place to isolate
aquifers overlaying the reservoir. Pressure tests of
casing and cement are conducted prior to fracture
stimulation to guarantee the integrity of the well.
Well integrity
Fluid is pumped into the well at high pressure
and forced through perforations to create
fractures. Sand stays in the reservoir to keep
the fractures open, allowing the gas to flow
through to the well.
Hydraulic fracturing process
Geological integrity
The length of a fracture is carefully monitored.
Santos measures downhole pressure data onsite, in
real-time, to ensure the fracturing process pressure
signature matches planned modelled pressures.
The majority of fluids are recovered and any waste is
disposed of appropriately. Any fluid that remains in the
reservoir post completions process will be recovered
during normal production.
Waste water treatment
and recovery
Confining layers
Confining layers
Schematic: not to scale
Production zone
Aquifer
Conductor casing and cement
Surface casing and cement
Intermediate casing and cement
Production casing and cement
Fracturing can be conducted circa 500 to 3,500 metres
below the surface
What is hydraulic
fracturing?
Hydraulic fracturing, or fracking, is used
to increase the flow of oil or natural
gas from a well. It has been used safely
around the world since 1949 in over two
and a half million wells3
.
Santos has used fracking to produce
oil and gas in South Australia and
Queensland for nearly 50 years. It has
also been used in other industries to
increase the flow of water wells or
to clean up hazardous waste sites4
.
In over 60 years of operations, there
has not been one proven case of water
contamination as a result of fracking5
.
Studies in the United States6
, United
Kingdom7
and here in Australia have
concluded that fracking can be
undertaken safely.
How does hydraulic fracturing work?
A well is drilled into an underground layer that contains oil or gas. The well is
surrounded by steel and concrete to ensure there is no link between the oil or gas
layer and other underground layers, such as aquifers.
Fluid is pumped into the layer containing oil or gas at high pressure. The pressure
of the fluid fractures the layer to produce tiny cracks. The fluid contains sand,
which remains underground to hold open the tiny cracks. This creates pathways
for oil or gas to flow more easily, increasing the productivity of the well.
The rest of the fluid is pumped back to surface and stored in specially designed
dams or tanks. The fluid is then reused in hydraulic fracturing, treated or disposed
at an approved facility.
Why do you need to use fracking?
Fracking enables extraction of oil and gas trapped in tight underground layers
that were not previously accessible. In this way, the increased use of fracking is
providing more energy to meet growing global demand and keep prices reasonable
for consumers.
Because fracking increases the flow from a well, it also means fewer wells need
to be drilled to deliver the same amount of oil or natural gas. This is good news for
landholders and for the environment.

3. See next page
for industry
references to
more information
Santos
and fracking
Santos has been fracking wells
in Australia safely for almost
50 years. Most of these wells
have been conventional oil and
gas wells. Contrary to popular
misconceptions, fracking is
not widely used in Coal Seam
Gas (CSG). Of the 1,844 CSG
wells drilled in Australia over
15 months during 2012 and
2013, only 6 per cent were
hydraulically fractured.10
At Santos, we’ve used
fracking to prolong the life
of depleted reservoirs in the
Cooper Basin. In NSW, the
CSG underpinning the Narrabri
Gas Project is unlikely to
require fracking. Horizontal
drilling is the preferred method
of developing NGP coal seams.
How is underground water protected?
According to the CSIRO, groundwater contamination from fracking fluids is
considered a low risk8
.
The underground layers containing gas are geologically separated from other
underground layers and all wells are surrounded by steel and concrete. This ensures
no movement of fracturing fluid into aquifers.
Even in the highly unlikely event that there was some connection between
fracturing fluid and an aquifer, the CSIRO concludes that the risk of contamination
would be minimised because during production water would flow away from the
aquifer and towards the well9
.
TAS
VIC
NSW
QLD
SA
NT
WA
Australian Gas Reserves – conventional,
unconventional & coal bed methane
What’s in
fracking fluid?
Fracking fluid is 99 per cent water
and sand. A very small amount of
chemicals are also used to reduce
friction, remove bacteria, dissolve
some minerals and improve the
transportation of sand.
The chemicals are not unique to the
oil and gas industry and are found in
many household products such as
toothpaste, baked goods, ice cream,
food additives, detergents and soap.
Detailed information about the
chemicals used in Santos’ operations
is available at www.santos.com/coal-
seam-gas/hydraulic-fracturing.aspx.
90%
9.5%
0.5%
Water
Sand
Chemical additives

4. Registered and Head Office
Ground Floor, Santos Centre
60 Flinders Street
Adelaide South Australia 5000
GPO Box 2455
Adelaide South Australia 5001
Telephone: 61 8 8116 5000
Facsimile: 61 8 8116 5050
www.santos.com
Santos – an Australian Pioneer
An Australian energy pioneer since 1954, Santos is
a leading oil and gas producer, supplying Australian
and Asian customers. With over 3,000 employees
across Australia and Asia, Santos’ foundations are
based on safe, sustainable operations and working
in partnership with host communities, governments,
business partners and shareholders.
Industry references
1. What is hydraulic fracturing?, CSIRO, 2012
2. Evaluation of Impacts to Underground Sources of Drinking Water by Hydraulic Fracturing of Coalbed Methane Reservoirs, US EPA, June 2004a
3. Hydraulic fracturing 101, Society of Petroleum Engineers, 2012 (http://www.kgs.ku.edu/PRS/Fracturing/Frac_Paper_SPE_152596.pdf)
4. A Citizen’s Guide to Fracturing, US Environmental Protection Agency, 2001
5. Just the facts, Energy In Depth, 2015 (http://energyindepth.org/just-the-facts/). The US Department of the Interior, US Environmental
Protection Agency and regulators in 11 US States have confirmed no proven water contamination from hydraulic fracturing.
6. Hydraulic fracturing 101, Society of Petroleum Engineers, 2012 (http://www.kgs.ku.edu/PRS/Fracturing/Frac_Paper_SPE_152596.pdf)
7. Shale gas extraction in the UK: a review of hydraulic fracturing, Royal Society & Royal Academy of Engineering, 2012 (https://royalsociety.
org/~/media/policy/projects/shale-gas-extraction/2012-06-28-shale-gas.pdf)
8. Frequently asked questions on coal seam gas extraction and fracking, GISERA (CSIRO & APLNG), 2011 (http://www.gisera.org.au/
publications/faq/faq-csg-extraction-fraccing.pdf)
9. What is hydraulic fracturing?, CSIRO, 2012
10. Hydraulic fracturing background review, Australian Department of Environment, June 2004.
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