Version 2
Updated May 2014
International
Association
of Oil & Gas
Producers
WE ARE WORKING FOR SAFE, SUSTAINABLE
GAS FROM SHALE…
EXPLORATION & DEVELOPMENT IN EUROPE
• Is an affordable, efficient energy source.
Successful exploration of gas from shale could
potentially provide Europe with an additional
source of secure and competitive energy that
could make an immediate and positive impact
on reaching the EU’s ambitious CO2 reduction
targets. OGP members are committed to work for
its safe, responsible development in Europe.
• Has a smaller environmental footprint with
lower GHG emissions and a lower surface
footprint than other conventional energy.
WHAT IS GAS FROM SHALE?
It is natural gas that can only be economically
extracted from sedimentary shale rock through the
combined use of horizontal drilling and hydraulic
fracturing. It shares many of the advantages of
natural gas that has been produced safely in
Europe for many years.
• Reduces CO2 emissions. Between 2007
and 2012 the US cut CO2 emissions by
450 million tons thanks to the shift from
coal to gas in power generation.
• Is abundant. IEA estimates show that
reserves of natural gas extracted from
unconventional sources, like gas from shale,
coal bed methane and tight gas almost
double recoverable gas resources (using
current technology and economic models).
• Has potential for economic benefits such as
increased employment, tax revenues and
royalties.
• Contributes to supply diversity and security
for Europe by increasing domestic supplies.
RESPONSIBLE DEVELOPMENT
EXISTING REGULATION REDUCES RISK
OGP acknowledges the importance of industry
and authorities cooperating and establishing a
dialogue to address public concerns through the
open sharing of information and knowledge.
Industry experience has demonstrated that
early dialogue with local communities is the
most important element of maintaining the trust
necessary for successful development.
European legislators have ensured that the
exploration and production of natural gas in Europe
is one of the most highly regulated processes in
the world. In fact, gas from shale development is
regulated by 14 different pieces of EU legislation,
as well as a strong existing regulatory regime at
national and local level. OGP and its members
work within the effective implementation of existing
regulations and recognise that this is an important
factor in reducing risk for all gas operations.
As part of our efforts to build trust OGP has
developed a Transparency Initiative for European
drilling projects. It has created a public hydraulic
fracturing disclosure website where members of
the public can search for nearby well sites that
have been hydraulically fractured to see what
chemicals were used to fracture natural gas
resources on a well-by-well basis.
You can fin
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the most
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– F.A.Q.s on seism
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What happened in
the Blackpool area
of the UK in 2011?
ring
It is an onlin
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easy-to-und
answers to
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questions c
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the US (Texas, 2008/
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reg
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risk assessments
to set
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prior to drilling
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wells for fluid
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should be avoided
should be set
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CHEMICAL
S
GREENHOU
SE
GASES
SEISMICITY
WATER
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
1
Do you sample groundwater when drilling and
hydraulic fracturing a well?
OGP companies believe it is best practice to sample existing groundwater sources in a
predetermined vicinity of a new well site both prior to and after drilling and fracturing, as well as
during the production phase. Such testing is normally part of an Environmental Impact Assessment
and/or part of the drilling permit.
Depending on applicable regulations, local conditions and operator’s policies, the testing may
include surface water such as rivers, ponds or lakes but also water wells to sample aquifers.
Understanding the quality of water is an important component of water source management.
For example, The Polish Geological Institute tested 17 water wells and one creek in the vicinity
of the Lebien LE-2H well before and after drilling and completion. They found no evidence of any
change in surface or ground water quality.
FIGURE 1: GROUNDWATER IS TESTED BEFORE AND AFTER DRILLING AND COMPLETION
Baseline tests measure:
Levels of iron & solids
Organic matter
Methane
NORM
2
Testing also
occurs after drilling
& fracturing
How much water do you use to drill a well and to
hydraulically fracture it?
To drill a vertical exploration well to a depth of about 3500m approximately 500 to 750 m3 of water
will be used to formulate the drilling mud. To perform a multi-stage hydraulic fracturing operation
one will use an average of 10,000 to 20,000 cubic metres (m3) of water. In Poland, the water used
for the Lebien LE-2H well totalled approximately 18,000 m3 (to drill the well to a depth of 4,000
metres and perform 13 hydraulic fracture stages over a horizontal distance of 1,000 metres).1
Note: 20,000m3 represents the annual water usage (direct and indirect) of 8 to 16 people.
http://www.waterwise.org.uk/data/resources/25/Water_factsheet_2012.pdf
FIGURE 2: TYPICAL WATER USE FOR HYDRAULIC FRACTURING OPERATIONS IN EUROPE
WELL DRILLING
500-750m
3
FRACTURING
ANNUAL WATER USE OF
(5-15 STAGES)
8-16 PEOPLE
10,000-20,000m3
10,000-20,000m3
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
3
How much water is used to develop a typical shale
gas deposit?
According to the Massachusetts Institute of Technology, in the United States, water used for drilling
and hydraulic fracturing shale gas wells represents less than one percent of total water usage in the
areas where major shale gas deposits are being developed.3
Operations for a typical shale gas basin in early production phase could require drilling about 100
hydraulically fractured wells per year (multi-well drill pads with 10–20 wells). At 18,000 m3 per well
(and assuming no water re-use) it would result in annual water use of less than 0.02% of annual
industrial water use in Poland4.
Water from shale gas operations is commonly re-used. Between 20 and 40% (sometimes up to
70%) of the water injected in the geological formation as part of a hydraulic fracturing treatment is
recovered on the surface and stored. Typically the water recovered approximately 2-5 weeks after
a hydraulic fracturing treatment is known as flowback water (see Section 5). Gas wells will also
deliver to the surface water bearing the gas formation. This water is typically non-potable (salty)
and is know as produced water. The reuse of produced and flowback waters reduces the amount
of water needed. In the Marcellus Basin in Pennsylvania, some operators reuse nearly 100% of the
flow back/produced water, while in other basins the reuse if less prevalent than in the Marcellus, is
generally increasing.
FIGURE 3: EXAMPLES OF WATER USAGE IN SHALE GAS OPERATIONS
100 X 18000 m3 = less
than 0.02% of annual
freshwater industrial
water use in Poland
In the US, water used for
drilling & hydraulic fracturing
shale gas wells represents
less than 1% of total water
usage in the areas where
the deposits are being
developed.
In the Marcellus Basin, in
Pennsylvania, recycling
of produced water is
approaching 100%
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
4
Reducing the surface footprint:
Figure 4 shows a typical example of
a multi-well pad development. In this
case, 8 horizontal multifractured wells
have been drilled from a single pad.
This technology reduces the surface
footprint while efficiently producing
the resource. The hydraulic fracturing
process normally lasts 3-5 days and
takes place after the eight wells have
been drilled, cased and cemented,
and the drilling rig has been removed.
FIGURE 4: MULTIPLE HORIZONTAL WELLS FROM
SINGLE PAD
MULPTIPLE HORIZONTAL WELLS FROM SINGLE PAD
3000m
1.5km
The most widely metrics used to
quantify the level of water used in
shale production, is energy water
intensity which compares the volume
of water used to produce a fuel to
the amount of energy produced (e.g.
cubic meters of water per megawatt
hour). There is consensus among
researchers that the energy water
intensity of shale gas is relatively
small compared to that of other types
of fuels. This has been documented
by the Groundwater Protection
Council for the US Department of
Energy and a comparison of energy
water intensity for the production of
various sources of energy is shown in
Figure 5.5.
FIGURE 5: ENERGY WATER INTENSITY
0.450
0.400
CUBIC METRES/MWh
5
Energy water intensity:
0.350
LOW
0.300
MEDIUM
0.250
HIGH
0.200
0.150
0.100
0.050
0.000
DEEP SHALE
GAS
NUCLEAR
COAL
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
6
Where do you get the water required to drill a well
and hydraulically fracture it?
Before drilling and fracturing a well, operators commission comprehensive studies to evaluate
the sustainability of the water supply and to develop a resources management plan. This process
includes consideration of volume and water quality requirements, regulatory and physical
availability, competing uses, proximity, means of transport and characteristics of the geologic
formation to be fractured (including water quality required to fracture it). The range of water sources
available can include:
• freshwater water sources produced from water wells specifically drilled
• surface water, such as rivers and lakes
• municipal water supplies
• treated waste water
• deep non-fresh water sources
• recycled water from earlier fracturing operations
FIGURE 6: A WATER SUPPLY EVALUATION IS COMPLETED PRIOR TO DRILLING
The range of water sources might include:
Surface water
Recycled
fracturing water
Wells connected to known
water sources
Treated waste water
Municipal water
supplies
Deep non-fresh
water sources
Approved permits consider:
Availability
Competing uses
Proximity
Geologic formation characteristics
Water is drawn over time & stored for
use when larger amounts are required
minimising impact on water availability
for other uses.
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
7
What happens to the hydraulic fracturing fluid
injected into the ground?
8
Can hydraulic fracturing fluid affect our drinking
water?
The water injected during hydraulic fracturing either stays in the formation or is returned to the
surface mixed with the natural gas resource during production. Depending on the nature of the
geological formation, between 20 and 40% (sometimes up to 70%) of the water used for hydraulic
fracturing is recovered during the first two to five weeks of hydrocarbon production. This part of
injected water recovered is known as flowback water. Shale formations also have naturally water
within its pore spaces and part of this water can be recovered to surface too. This is known as
produced water. Flowback and produced water is collected stored in open pits or closed tanks and
then recycled, treated or disposed of according to government approved methods.
There has been no proven
documented case of hydraulic
fracturing operations contaminating
drinking water resources. Natural
shale gas-bearing formations
generally tend to be separated
from underground water sources
by 1-3 kilometres of rock. During
the hydraulic fracturing process,
water is injected into these deposits,
along with proppant (sand) particles
and additives. The composition of
the hydraulic fracturing fluid varies
according to the properties of the
shale target formation. The volume
of the fluid is about 90% water,
9.5% proppant (sand) particles, and
on average 0.5% additives. The
additives can serve a number of
purposes, including:
• friction reduction
(as the fluid is injected)
• prevention of bacterial growth)
• scale inhibition (to prevent mineral
precipitation)
• corrosion inhibition
• clay stabilisation (to prevent swelling
of expandable clay minerals)
• viscosifying the water for supporting
proppants
FIGURE 7: WHAT IS IN A TYPICAL FRACTURING
FLUID?
90%
water
9.5%
proppant (sand)
particles
0.5%
additives
WHAT DO THE ADDITIVES DO?
reduces friction (as fluid is injected)
prevent bacterial growth (biocides)
inhibit scale (to prevent mineral
precipitation)
inhibit corrosion
stabilise clay (to prevent swelling of
expandable clay materials)
support proppants (gelling agent)
promote fracturing (surfactant)
clean (well bore & formation)
FIGURE 8: MICROSEISMIC MEASUREMENTS OF
DISTANCE FROM FRACTURES TO WATER SOURCE
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
OGP supports the on-line disclosure of the chemical additives used in hydraulic fracturing and
has developed a website where companies operating in Europe can disclose the chemicals used
in their wells: ngsfacts.org Similar initiatives are www.fracfocus.org in the United States or are
currently listed on several of our member’s web sites.
The fluid injected into the shale formation bearing gas creates fractures that allow the trapped gas
to flow to the wellbore. The hydraulic fracturing process only stimulates the geologic formation of
interest. The extent of such fractures generates small seismic events. They can be measured by
using highly sensitive seismic recorders and allow to map the vertical fracture extension. Typically
the fracture zone extends a few tens to a few hundred meters upward from the well bore. According
to several thousands of seismic measurements, the probability that any fractures extend vertically
upward beyond 1000 feet (350 metres) is nearly nil. This is because layered sedimentary rocks
provide natural barriers to the progression of the fracture and prevent any water, gas or chemicals
from reaching a shallow water source6. Figure 8 (above) shows through a series of micro seismic
measurements performed in the United States the extent of the fracture top7.
For a typical European shale gas well such results leave a distance of 1 to 3 kilometres between
the top fracture and the water source. Figure 9 provides a scale illustration of the distance between
the ground water aquifers and the rock formations that are being fractured.
FIGURE 9: WELL CONSTRUCTION AND DISTANCES EXAMPLE
EIFFEL TOWER
AQUIFER
324m
conductor casing
surface casing
intermediate casing
production casing
QUADRUPLE CASING
Layers of steel encased in
cement protect ground water
3000m
1000–
3000m
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
9
10
11
Can drilling fluid affect our drinking water?
Although the well bore penetrates water sources near the surface, it is protected from produced
water or hydrocarbons by multiple layers of impermeable cement and steel casing. As shown at the
top of Figure 9, integrity of each cemented casing is tested prior to hydraulic fracturing. This type
of well design and construction is a standard oilfield technique that prevents hydrocarbons from
entering any water source.
Is hydraulic fracturing a mature technology?
Hydraulic fracturing has been used in over 1 million wells world-wide since the 1940’s8 and
comprehensive studies have found no historical cases in which hydraulic fracturing has
contaminated drinking water 9. The UK Department of Energy and Climate Change (DECC)
concluded early 2012 that “In the light of the robust controls in place to protect the environment and
ensure safe operation, DECC see no need for any moratorium on shale gas’development”. This
is also the view of the (UK) Energy and Climate Change Select [parliamentary] Committee, which
held an inquiry into shale gas in 2012 and took evidence from government, regulators, the British
Geological Survey, the oil and gas industry. The UK Energy and Climate Change Select committee
also concluded that hydraulic fracturing does not pose a direct risk to water sources, provided that
the well-casing is intact. Any risks that do arise are more likely to be related to the integrity of the
well, and are no different to issues encountered when exploring for and producing hydrocarbons
from conventional geological formations10.
Can you recover the water used in hydraulic
fracturing?
This depends on the geology of the
shale formation. During hydraulic
fracturing typically 20% to 40% of
the water used is recoverable in
the first 2-5 weeks of production.
This is termed “flowback” water.
The flowback water flows to the
surface and is separated from the
natural gas. This water may contain
suspended clay particles, dissolved
inorganic components from the
shale, inorganic compounds from
the hydraulic fracturing fluids and
hydrocarbons from the reservoir as
well as sand and silt particles from
the shale or proppant. Some of the
time, producing gas wells will also
deliver water to the surface from the
gas bearing formation,
FIGURE 10: CAN USED WATER BE RECOVERED?
Water flows to the
surface & separates
from the gas
iron & solids
organic matter
methane
NORM
Water is shipped to
processing facility or
recycled at surface
& re-used
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
the water is typically non-potable (salty) and is know in the industry as produced water. Appropriate
government authorities issue permits for handling and disposal of flowback/produced water. This
procedure is consistent with the EU Mining Waste Directive.
The water can then be shipped to licensed water processing facilities or recycled at the surface
and re-used for subsequent hydraulic fracturing operations. As a reference, the British Columbia
Oil and Gas Commission has estimated that 20% of the water used in hydraulic fracturing for Horn
River Basin, Canada comes from the reuse of flowback water11. Various treatment technologies
allow the produced water to be reused for other drilling and hydraulic fracturing operations or other
industrial uses.
FIGURE 11: VARIOUS WATER MANAGEMENT STEPS
Source
Transport
Recycle/disposal
Store
Treat
12
Store
Utilise
Does the water used in drilling or hydraulic
fracturing have radioactive material in it?
Some rocks naturally contain trace levels of minerals that are radioactive. Depending on the
regional and sedimentary environment, water used in the exploration and production process
(whether in typical sandstone reservoirs or shale) may contain low levels of radioactivity through
contact with this naturally occurring radioactive material (or ‘NORM’). NORM is also found in the
air, soil, water, and in many of our foods low (normal) background levels.
Any radioactive material exceeding regulatory requirements that would be leached from the
subsurface during drilling, hydraulic fracturing or production operations and flown back up the well
bore would be contained and disposed of at certified waste treatment/disposal facilities. NORM
contained in flowback and produced waters typically presents very low risks. In a recent study of
outflow from treatment plants or water used in the Marcellus Basin in Pennsylvania, the test results
showed that treated water contained levels of radioactivity lower than normal background levels.12
.
…SHALE GAS OPERATIONS
Frequently asked questions about water
This document provides factual information about shale gas operations and water
FIGURE 12: WHAT IS NORM?
Naturally Occurring Radioactive Material is found in:
air
soil
Water may absorb low
levels of radioactivity
through contact with
NORM
food
water
Any radioactive material absorbed
during operations that flows back up
the well bore is contained & disposed of
The resulting
NORM in
recovered
water is very
low
References
Polish Geological Institute – Environmental impact of hydraulic fracturing treatment performed on the Lebien LE-2H well, 2012
http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Water_statistics
3
Polish Geological Institute – 2010 figures
4
Massachusetts Institute of Technology – The Future of Natural Gas, 2011
5
Ground Water Protection Council, for U.S. Department of Energy
6
Richard J. Davies et al – Hydraulic Fractures, How far can they go? Durham Institute, Marine and Petroleum Geology, 2012
7
Kevin Fisher – “Data Confirm Safety of Well Fracturing,” The American Oil & Gas Reporter, July 2010
8
SPE – Hydraulic Fracturing, History of an Enduring Technology, 2010
9
USDOE and GWPC Study – State Oil and Natural Gas Regulations Designed to Protect Water Resources, 2009
10
UK Department of Energy and Climate Change – http://www.decc.gov.uk/en/content/cms/meeting_energy/oil_gas/shale_gas/shale_gas.aspx
11
Campbell Matt Horne and Karen Campbell – Shale gas in British Columbia: Risks to B.C.’s water resources, Pembina Institute, September 2011
12
Pennsylvania Department of Environmental Conservation –
http://www.portal.state.pa.us/portal/server.pt/community/newsroom/14287?id=16532&typeid=1
1
2
…SHALE GAS OPERATIONS
Frequently asked questions about chemicals
This document provides factual information about shale gas operations and chemicals
1
Are you prepared to carry out baseline testing of
drinking water sources? What is typically included
in baseline testing?
OGP companies believe it is best practice to sample existing groundwater sources in a predetermined vicinity of a new well site both prior to and after drilling and fracturing. Depending on
applicable regulations, local conditions and operator policies, the testing may include water wells
and surface water such as rivers, ponds or lakes in the immediate vicinity of the planned well.
Such testing is normally part of an Environmental Impact Assessment and/or part of the drilling
permit. Baseline testing is also one of the IEA’s “Golden Rules for a Golden Age of Gas” (Measure,
Disclose, Engage)
Providing authorities with a clear understanding of the chemical status of water sources before
and after drilling and completion is an important part of water source management and should be
done in line with local laws and regulations. Authorities may then choose to make this information
publicly available to local communities.
Baseline tests typically include measuring levels of iron, solids, organic matter, naturally occurring
radioactive material (or ‘NORM’) and methane.
Measuring baseline methane is an important way to differentiate between thermogenic methane
originating from an oxygen deficient environment and biogenic methane that can be found in
environments such as lakes, ponds and shallow water sources/water wells before development
activities even commence.
FIGURE 1: GROUNDWATER IS TESTED BEFORE & AFTER DRILLING AND COMPLETION
Baseline tests measure:
Levels of iron & solids
Organic matter
Methane
NORM
IEA’s
ULES
GOLDEN R
Real-world example
MEASURE
DISCLOSE
What is NORM?
Naturally Occurring
Radioactive Material is found in:
ENGAGE
AIR
Testing also occurs after
drilling & fracturing
SOIL
Water may absorb low
The Polish Geological Institute tested 17 water wells and
one creek in the vicinity of the Lebien LE-2H well before
and after drilling and found no evidence of any change in
surface or ground water quality as a result of the drilling
or hydraulic fracturing processes for the well.
Source: Polish Geological Institute – Environmental impact
of hydraulic fracturing treatment performed on the Lebien
LE-2H well, 2012
…SHALE GAS OPERATIONS
Frequently asked questions about chemicals
This document provides factual information about shale gas operations and chemicals
2
Are you prepared to disclose chemicals in
fracturing fluids publicly?
Yes, we are committed to keeping people well informed about additives used in their local
area. Many OGP members who are active in shale gas exploration in Europe already disclose
information via various industry initiatives or on their company websites, even though the number
of shale gas fracturing operations in Europe is currently very small.
In order to address the need for greater transparency, OGP supports the public disclosure of the
additives used in hydraulic fracturing (such as fracfocus.org in the United States or as currently
listed on several of our members web sites). The full disclosure of fracturing fluid additives and
volumes is one of the IEA’s “Golden Rules for a Golden Age of Gas” (Measure, Disclose, Engage).
3
What proportion of the fracturing fluid is made
up of chemicals?
All hydraulic fracturing fluids contain
a small proportion of additives. These
fulfil very specific purposes, such as
controlling the physical properties of
the fracturing fluids and its interaction
with the formation racks and fluids,
controlling rust or reducing bacteria
levels and to improve the overall
productivity of the well. On average,
chemical additives make up only
0.5% of a fracturing fluid. Most of
the chemicals are used in everyday
life by individuals as food additives,
in personal hygiene products or in
household cleaners
FIGURE 2: OGP SUPPORTS PUBLIC DISCLOSURE
.
E ON..
OSUR
DISCL
als
Chemic
es
Additiv
g
in
k
Frac ons
operati
use
Water
REGULATORS
COMMUNITIES
4
Are you prepared to register your fracturing fluid
additives under REACH?
5
Are you prepared to list components by proportion/
by %?
Yes. All additives in fracturing fluids that exceed the one metric tonne threshold and other
requirements set by REACH must be registered at ECHA by the manufacturer or importer.
Yes, OGP supports the public online disclosure of the additives used in hydraulic fracturing (such
as ngsfacts.org in Europe, fracfocus.org in the United States or as currently listed on several of our
members websites), which includes maximum component concentrations.
…SHALE GAS OPERATIONS
Frequently asked questions about chemicals
This document provides factual information about shale gas operations and chemicals
6
Are you prepared to disclose specific details of
individual fracturing operations?
7
Are you prepared to disclose water use per well?
Yes, OGP supports the public on-line disclosure of the additives used in hydraulic fracturing on-line
(such as ngsfacts.org in Europe, fracfocus.org in the United States or as currently listed on several
of our members’ websites), which includes well-by-well statistics.
Yes, OGP recognises the importance of appropriately managing and conserving water. It is
accepted industry practice in the United States to disclose how much water has been put into a well
during hydraulic fracturing and OGP supports this practice.
It is also important for operators to record water usage and in some countries, such as Poland,
operators must measure and report all water used in order to comply with the terms of permits.
8
What is your position with regard to “intellectual
property”?
OGP supports the public disclosure
of additives used in fracturing
operations consistent with the
European regulatory structure and
REACH processes. Our suppliers
are already aware of the importance
of public disclosure of additives and
are in dialogue with our members
about the best way to do this for
European audiences.
Geologic and reservoir
characteristics such as mineralogy,
rock strength, permeability, reservoir
fluid composition, pressure, and
temperature are just a few of the
factors considered in selecting an
appropriate fracturing fluid. Service
companies have developed a number
of different hydraulic fracturing
fluid recipes to more efficiently
induce and maintain productive
fractures. These solutions have
unique characteristics and therefore
the exact concentrations of some
additives are protected as proprietary
information. OGP recognises
that intellectual property rights
FIGURE 3: STRIKING A BALANCE ON DISCLOSURE
OGP supports
disclosure as per EU
regulations & REACH.
Suppliers understand the
importance of such
disclosure
Companies
need to protect their
intellectual property to remain
competitive & benefit from their
investment, which drives further
innovation & investment
…SHALE GAS OPERATIONS
Frequently asked questions about chemicals
This document provides factual information about shale gas operations and chemicals
are critical for businesses – these rights enable business to benefit from their investments and
remain competitive in the global marketplace. Any disclosure process needs to include protection
for the intellectual property represented in some chemical makeups and concentrations in the
hydraulic fracturing fluid. We believe fracfocus.org in the United States has managed to provide
unprecedented amounts of information on hydraulic fracturing fluids, including even non-hazardous
constituents, while protecting vital intellectual property that allows for continued innovation and,
hence, improvement.
9
What is NORM?
A NORM is Normally Occurring Radioactive Material that is also found in the air, soil, water, and
in many of our foods at normal background levels. Some rocks naturally contain trace levels of
minerals that are radioactive. NORM in water used in the exploration and production process
typically presents very low risks. A recent Pennsylvania Department of Environmental Conservation
study of the outflow from treatment plants for water used in the Marcellus Basin in Pennsylvania
showed that treated water contained levels of radioactivity lower than normal background levels.
Depending on the regional geological and sedimentary environment, water used in the exploration
and production process (whether in typical sandstone reservoirs or shale) may absorb low levels
of radioactivity through contact with this naturally occurring radioactive material. Any radioactive
material that is absorbed from the subsurface during drilling, hydraulic fracturing or production
operations and flows back up the well bore is contained and disposed of at certified waste facilities.
FIGURE 4: WHAT IS NORM?
Naturally Occurring Radioactive Material is found in:
air
soil
Water may absorb low
levels of radioactivity
through contact with
NORM
food
water
Any radioactive material absorbed
during operations that flows back up
the well bore is contained & disposed of
The resulting
NORM in
recovered
water is very
low
…SHALE GAS OPERATIONS
Frequently asked questions about seismicity
This document provides factual information about shale gas operations and seismicity
1
Does hydraulic fracturing increase the risk of
earthquakes?
No. A recent study from the Department of Environmental Conservation of New York State reached
the conclusion:
“There is a reasonable base of knowledge and experience related to seismicity induced by
hydraulic fracturing. Information reviewed in preparing this discussion indicates that there
is negligible increased risk to the public, infrastructure, or natural resources from induced
seismicity related to hydraulic fracturing. The microseisms created by hydraulic fracturing
are too small to be felt, or to cause damage at the ground surface or to nearby well”1.
2
What are the magnitude and intensity ranges of
earthquakes (natural seismicity)?
FIGURE 1: EARTHQUAKE CAUSED
BY FAULT SLIP
Earthquake is a term used to describe the ground shaking
and radiated seismic energy caused by sudden slip on
a fault, or by volcanic or magmatic activity, or by other
sudden release of built up stress in the earth.
The effect of an earthquake can vary from minute tremors
not felt at the surface to extreme ground shaking causing
very heavy damage. The strength of an earthquake can
be expressed in terms of both magnitude and intensity as
described below.
Earthquakes occur when ruptures or fractures
in the earth slip along a plane, such as a fault
or joint, releasing energy as seismic waves
that can cause shaking and movement of the
ground at the surface
The Magnitude Scale2 is related to the amount of seismic
energy released at the hypocenter of the earthquake.
It is based on the measurement of the amplitude of
the earthquake waves recorded on instruments which
have a common calibration. The Magnitude Scale is a
base10 logarithmic scale obtained by calculating the
logarithm of the amplitude of seismic waves measured by
a seismograph. For example, a magnitude 4 earthquake
generates a seismic wave amplitude 10 times larger (or
31 times more energy release) than a seismic amplitude
created by a magnitude 3 earthquake.
The Modified Mercalli Intensity scale2 is based on the
observed effects of ground shaking on people, buildings,
and natural features. It varies from place to place within the
disturbed region depending on the location of the observer.
The relationships between the effect of an earthquake and
its magnitude and intensity scales are summarized
in Table 1.
…SHALE GAS OPERATIONS
Frequently asked questions about seismicity
This document provides factual information about shale gas operations and seismicity
TABLE 1: MAGNITUDE AND INTENSITY SCALES – TYPICAL EFFECTS AND FREQUENCY OF EARTHQUAKE2
Perceived
Shaking
Potential
Damage
Not felt
Weak
Light
Moderate
Strong
Vibration
similar to
the passing
of a truck
Felt
indoors
by many,
outdoors
by few
during
the day
Felt by
nearly
everyone;
many
awakened
Felt by all
Very Light
None
Very
Strong
Severe
Violent
Extreme
Light
Moderate
Moderate to
Heavy
Heavy
Very Heavy
Some
dishes,
windows
broken
Some
instances
of fallen
plaster
and heavy
furniture
movement
Slight to
moderate
damage in
well-built
ordinary
structures
Considerable
damage in
ordinary
substantial
buildings
with partial
collapse
Great
Damage in
substantial
buildings
with partial
collapse.
Buildings
shifted off
foundations
Most
masonry
and frame
structures
destroyed
with
foundations.
Rail bent
VII
VIII
IX
X+
15 per year
1 per year
Modified
Mercalli
Intensity
I
II-III
IV
V
VI
Richter
Magnitude
<2
2 to 2.9
3 to 3.9
4 to 4.9
5 to 5.9
Frequency
of
Worldwide
Occurrence
Continual
1,300,000
per year
(est.)
130,000
per year
(est.)
13,000
per year
(est.)
1,319 per year
3
7+
6 to 6.9
134 per year
What is induced seismicity?
Induced seismicity is the phenomenon where human activity alters the frequency of occurrence
and the magnitude of seismic events from natural levels.
Industrial activities that can induce seismicity include:
• Construction (e.g., impounding water behind a dam, tunneling, pile driving)
• Mining activity (e.g., quarrying, coal mining)
• Industrial presses
• Heavy vehicle movements (e.g., vibrating rollers)
• Underground injections for fluid disposal
• Oil and gas operations
• Geothermal energy production
…SHALE GAS OPERATIONS
Frequently asked questions about seismicity
This document provides factual information about shale gas operations and seismicity
4
What is hydraulic fracturing?
FIGURE 3: HYDRAULIC
FRACTURING
In shale gas operations, hydraulic fracturing is a part of
well completion process and involves injecting a fluid into
a formation at a pressure sufficient to generate a crack or
fracture. Shale gas is produced by drilling horizontally and
hydraulically fracturing a target shale formation, typically
one to three kilometers beneath the surface. Hydraulic
fracturing operations involve many injection stages with
each stage lasting a few hours and the total operation
may last up to 5 days per well. This completion process
results in injection of water, proppant (sand) and a small
concentration of chemical additives into the shale under
controlled pressures to create fractures, enhancing the
formation surface area exposed thus improving the natural
gas and liquids flow to the surface.
Hydraulic fracturing releases energy deep
underground, creating low levels of
siesmic activity that generally cannot be
felt at the surface
5
What are the risks of induced seismicity from
hydraulic fracturing?
Hydraulic fracturing releases energy deep underground, creating extremely low levels of seismic
activity typically below minus 0.8 (-0.8) on the Richter scale that generally cannot be felt at the
surface. The energy release by this extremely low level of seismicity is less than 0.01% of an
earthquake of magnitude 2. Moreover, it is a temporary process, generally lasting only a few hours.
Over one million wells have been hydraulically fractured worldwide. Until the end of 2013, there
are only three known cases —Bowland shale near Blackpool (UK), Horn River in British Columbia
(Canada), and Eola in Oklahoma (USA), where hydraulic fracturing could be linked to the
occurrence of seismic events with magnitude between 2 to 3.8 (at most equivalent to vibration of a
passing truck—see Table 1). In these rare cases, a number of risk factors coincided, including the
potential for re-activation of existing faults.
In addition, a study by the Nation Research Council of the National Academies (USA) made
the following findings on hydraulic fracturing and induced seismicity: “The process of hydraulic
fracturing a well as presently implemented for shale gas recovery does not pose a high risk for
inducing felt seismic events”3. Other recent governmental or academic studies lead to similar
conclusions 4,5,6,7.
…SHALE GAS OPERATIONS
Frequently asked questions about seismicity
This document provides factual information about shale gas operations and seismicity
6
What happened in the Blackpool area of the UK in
2011?
In the UK, hydraulic fracturing was suspended at Cuadrilla Resources’ Preese Hall exploratory
site after a magnitude 1.5 event on 27 May 2011 in the Blackpool area and in light of a preceding
magnitude 2.3 event on 1 April 2011 5, 8, 9.
At that time the British Geological Survey (2011) commented: “We understand that fluid injection,
between depths of two to three kilometres, was ongoing at the Preese Hall site shortly before both
earthquakes occurred. The timing of the two events in conjunction with the fluid injection suggests
they may be related. It is well-established that fluid injection can induce small earthquakes.
Typically, these are too small to be felt.”
In a recent report, the UK Department of Energy and Climate Change (DECC) recognises the
low level of risk of induced seismicity below 3 on the Richter scale. Such events are “unlikely to
cause structural damage” and therefore the DECC could “see no reason why Cuadrilla Resources
Ltd. should not be allowed to proceed with their shale gas exploration activities. DECC went on
to recommend cautious continuation of hydraulic fracture operations, at the Preese Hall site.”10 In
December 2012, the UK government announced its decision to allow hydraulic fracturing to resume.
7
What measures are taken to further reduce the
potential risk of induced seismicity from HF in
active tectonic areas?
Sound pre-planning and surveying are measures that should be taken into account by operators and
reviewed by the regulator 10, 11. We support the inclusion of best practice in developing guidelines
appropriate for local conditions, which would enable exploration and production while addressing
public concerns. OGP is happy to offer assistance to the development of these guidelines.
FIGURE 3: SOUND PRE-PLANNING & SURVEYING CAN MITIGATE RISK IN AREAS PRONE TO
SEISMICITY
Geological risk assessments
should be conducted prior to
drilling fluid disposal wells
Faults with large, pre-existing
stress in brittle rock
formations should be avoided
Proper limits on flow rate
should be set
…SHALE GAS OPERATIONS
Frequently asked questions about seismicity
This document provides factual information about shale gas operations and seismicity
8
Is it likely that seismic activity would damage well
integrity and lead to leakage?
A study by the Department of Environmental Conservation of the New York State considers it very
unlikely, based on the existing track record of earthquakes in oil and gas producing areas of the
United States 12. In addition, the National Resource Council released a 225-page report on induced
seismicity in June 2012 that reinforces this position13.
References
1.
Department of Environmental Conservation, New York State — Revised Draft SGEIS on the Oil, Gas and Solution Mining Regulatory
Program (September 2011)
2.
California Geological Survey, Note 32, How earthquakes and their effects are measured (2002)
See also: US Geological Survey Website
3.
National Research Council - Induced Seismicity Potential in Energy Technologies (2012)
4.
Worldwatch Institute, Natural Gas and Sustainable Development Initiative — Addressing the Environmental Risks from Shale Gas
Development — Mark Zoback, Saya Kitasei and Bradford Copithorne, (July 2010)
5.
A report by researchers at the Tyndall Centre University of Manchester — Shale gas: an updated assessment of environmental and
climate change impacts, (January 2012)
6.
New York State Department of Environmental Conservation Division of Mineral Resources — Supplemental generic environmental
impact statement on the oil, gas and solution mining regulatory program (2011)
7.
Both carbon sequestration and liquid waste injection can induce seismic activity. Induced seismic events caused by deep well fluid
injection are typically less than a magnitude 3.0 and are too small to be felt or to cause damage. Rarely, fluid injection induces
seismic events with moderate magnitudes, between 3.5 and 5.5, that can be felt and may cause damage. Most of these events have
been investigated in detail and have been shown to be connected to circumstances that can be avoided through proper site selection
(avoiding fault zones) and injection design (Foxall and Friedmann, 2008). Department of Environmental Conservation, New York
State - Revised Draft SGEIS on the Oil, Gas and Solution Mining Regulatory Program (September 2011)
8.
Preese Hall shale gas fracturing — Review & recommendations for induced seismic mitigation (April 2012)
9.
Shale gas extraction in the UK: a review of hydraulic fracturing, Royal Society and Royal Academy of Engineering (June 2012)
10.
Preese Hall shale gas fracturing — Review & recommendations for induced seismic mitigation (April 2012)
11.
US department of Energy — Protocol for Addressing Induced seismicity Associated with Enhanced Geothermal Systems, DOE/EE0662, (January 2012)
12.
Wells are designed to withstand deformation from seismic activity. The steel casings used in modern wells are flexible and are
designed to deform to prevent rupture. The casings can withstand distortions much larger than those caused by earthquakes, except
for those very close to an earthquake epicenter. The magnitude 6.8 earthquake event in 1983 that occurred in Coalinga, California,
damaged only 14 of the 1,725 nearby active oilfield wells, and the energy released by this event was thousands of times greater than
the microseismic events resulting from hydraulic fracturing. Earthquake-damaged wells can often be re-completed. Wells that cannot
be repaired are plugged and abandoned (Foxall and Friedmann, 2008). Induced seismicity from hydraulic fracturing is of such small
magnitude that it is not expected to have any effect on wellbore integrity. Department of Environmental Conservation, New York State
— Revised Draft SGEIS on the Oil, Gas and Solution Mining Regulatory Program 6-326, (September 2011)
13.
National Research Council - Induced Seismicity Potential in Energy Technologies (2012)
…SHALE GAS OPERATIONS
…SHALE GAS OPERATIONS
– F.A.Q.s on greenhouse gases
Frequently asked questions about Green House Gases
This document provides factual information about shale gas operations and GHG
1
What is shale gas and what is the difference
between natural gas from shale and from other
reservoirs?
Shale gas is natural gas produced from sedimentary shale rock composed of organically rich mud
and clay. There is no difference in the natural gas produced from shale reservoirs and conventional
sources, such as sandstone, siltstones, limestone or dolomite reservoirs. Natural gas is essentially a
combustible mixture of hydrocarbon gases predominantly consisting of methane (CH4).
FIGURE 1: SHALE GAS IS NATURAL GAS
Hydraulic fracturing is
required to extract shale
gas from otherwise
impermeable shale
2
Once extracted, there is no
difference between natural
gas from shale rock and
from other reservoirs
Shale rock formations are found miles
below the earth’s surface. Generally,
the rock qualities for fluid storage
and flow capacity decrease as depth
increases due to the pressures
exerted by the earth’s weight. At great
depths, there may not be sufficient
permeability to allow hydrocarbons
to flow from the targeted formation
into the wellbore. Hydraulic fracturing
operations are essential to increase
the interconnectivity (permeability)
between pore spaces in the formation
in order to allow the hydrocarbons
to be exploited. Extraction of these
resources on a commercially viable
basis has been made possible by
the combination of two conventional
techniques called ‘horizontal drilling’
and ‘hydraulic fracturing’. Without
hydraulic fracturing, the shale rock is
simply too impermeable and valuable
gas would remain locked underground.
How does the Greenhouse Gas (GHG) footprint of
shale gas compare to that of conventional gas?
The Green House Gas (GHG) footprint of shale is comparable to that of natural gas produced from
other types of reservoirs.
Several studies have emerged in the past four years to estimate life-cycle emissions associated
with natural gas production, including shale gas. Given the early history of shale gas production and
assumptions involved in their estimates, results of these studies may vary and uncertainties in the
GHG estimates are recognized by these studies.
A study carried out by Prof William Griffith et al. of Carnegie Mellon University concludes that the
lifecycle footprint of shale gas from the Marcellus formation is only 3% higher than that of average
conventional gas in the United States1. The U.S. Argonne National Laboratory2 estimated that shale
…SHALE GAS OPERATIONS
…SHALE GAS OPERATIONS
– F.A.Q.s on greenhouse gases
Frequently asked questions about Green House Gases
This document provides factual information about shale gas operations and GHG
gas life cycle emissions are of the same magnitude as those of conventional natural gas1.
Two recent independent studies by the EPA and The University of Texas arrived at similar
conclusions in that the overall total emission from gas produced from shale and conventional
reservoirs are comparable. The University of Texas study, led by Dr. Allen, found that 2011
methane emissions from shale were 0.42% of natural gas produced in the US. In comparison,
the 2011 national emission inventory, reported by the EPA in 2013, estimates methane leakage at
0.47% of total US natural gas production3,4.
From these studies, it is clear that estimating and comparing the life-cycle GHG emissions from
natural gas production by conventional reservoirs and shale formations is a challenge due to a lack of
reliable data on emission rates for some of the phases and activities involved in shale gas production.
In general, the life-cycle of natural gas involves a number of phases, with varying amounts of GHG
emissions through each phase, as outlined below:
• Exploration. The same geophysical and geological methods are used to explore for shale gas
and conventional gas.
• Drilling and Completions. The only area where emissions from shale gas may differ from
gas produced from sandstone reservoirs is in the extraction process after drilling has been
completed. The difference in GHG emissions is only marginal due to the use of more energyintensive equipment to process produced gas into pipeline quality natural gas.
In addition, emissions of methane may occur following hydraulic fracturing and during well
completion. Some methane discharge can occur during the “flowback” step when the formation
fluids return to the surface with the hydraulic fracturing fluids (primarily water), immediately prior
to the well being routed to a gas/liquid separator, especially if using open disposal pits.
An industry practice known as reduced environmental completions (REC), or green completions,
can be used to limit GHG emissions from flowback activities. RECs involve routing gas during
flowback from the gas/liquid separator to a gas gathering line. If a gas gathering line is not
available flowback gas can be routed to a flare to reduce GHG emissions. However, GHG
emissions can also occur from flaring prior to being pipeline ready.
• Production, gathering and processing. There is no difference between the production,
gathering and processing of natural gas from different reservoirs.
• Transportation and Distribution. There is no difference between the transportation of
natural gas from different reservoirs. Emissions in this phase are dependent upon the mode
of transportation (truck, pipeline or LNG), the distance to the consuming market, and the
complexity of gas distribution. On average, transport-related emissions would be lower within
Europe than in Russia and most parts of the US, due to the proximity of these resources to
consumers5.
• Combustion. Over three quarters of the life-cycle emissions of natural gas are generated
during the combustion by the end-user. There are no additional emissions in the combustion of
shale gas compared to those of natural gas from other types of reservoirs.
…SHALE GAS OPERATIONS
…SHALE GAS OPERATIONS
– F.A.Q.s on greenhouse gases
Frequently asked questions about Green House Gases
This document provides factual information about shale gas operations and GHG
FIGURE 2: SHALE GAS GHG FOOTPRINT IS COMPARABLE TO GAS FROM OTHER RESERVOIRS
3/4 of
natural gas
life-cycle emissions
are generated here
Extraction
Processing
Transportation
Combustion
GHG emissions for shale
gas are marginally higher
due to more energyintensive equipment &
higher water use
Processing shale gas is
no more emission
intensive than gas from
other formations
There is no difference
between the emissions
of transportation of gas
from different reservoirs
There are no additional
emissions during
combustion of shale gas
compared to other types
of natural gas
When gas is used to generate
electricity the life-cycle GHG footprint
of shale gas is:
Less than 1/2
of hard coal
Less than 1/3 of
lignite-fired coal power
3
Is the emissions footprint of shale gas less than
other energy sources, and can it be further reduced?
Yes. The life-cycle GHG footprint of shale gas is less than half that of hard coal and less than a
third of lignite-fired coal power Industry6. Tighter pollution controls and technologies instituted by
the industry have already reduced the emissions of methane (CH4) and carbon dioxide (CO2) from
natural gas production. The gas industry is committed to further reduce emission from the life-cycle
of shale gas in the future7,8.
Preference for natural gas as energy source instead of coal or biomass also has an important
positive effect on today’s air quality. Burning gas emits very low emissions of nitrogen oxides and
sulfur dioxide – reducing acid rain and smog – and virtually no emissions of mercury or particulates
(PM2.5 or fine dust). Compared to coal, shale gas results in a 400-fold reduction of PM2.5, a
4,000-fold reduction in sulphur dioxide, a 70-fold reduction in nitrous oxides (NOx), and more than
a 30-fold reduction in mercury 9, 10.
…SHALE GAS OPERATIONS
…SHALE GAS OPERATIONS
– F.A.Q.s on greenhouse gases
Frequently asked questions about Green House Gases
This document provides factual information about shale gas operations and GHG
The 2013-published EU (UK)-centered study11 provides few quotable comparative emission
estimates, including:
“The carbon footprint (emissions intensity) of shale gas extraction and use is likely to be in
the range 200 – 253 g CO2e per kWh of chemical energy, which makes shale gas’s overall
carbon footprint comparable to gas extracted from conventional sources (199 – 207 g CO2e/
kWh(th)), and lower than the carbon footprint of Liquefied Natural Gas (233 - 270g CO2e/
kWh(th)). When shale gas is used for electricity generation, its carbon footprint is likely to be
in the range 423 – 535 g CO2e/kWh(e), which is significantly lower than the carbon footprint
of coal, 837 – 1130 g CO2e/kWh(e).”
Further improvements are expected to cut emissions from the drilling and production phases by
utilising additional or more efficient equipment and practices to prevent or capture CH4 emissions.
Implementation of rigorous preventative maintenance programs also helps reduce emissions.
• Use of efficient equipment. The use of natural gas or electricity instead of diesel to power
engines and equipment at the well-site is a potential source of emission reductions. Similarly, the
use of pipelines instead of trucks for the transport of water to and from the well-site can, under
certain conditions, further reduce the life-cycle carbon footprint of shale gas.
• Reduced Emission Completion (REC) well technologies. The water returned from the
hydraulic fracturing treatment may contain high concentrations of methane, some of which may
be flared or vented at the well-site. Reduced Emission Completion (REC) technologies — also
known as green completions — are techniques that separate and capture methane emitted
during well completions and flowback. This technique uses a system of piping, separators and
sometimes dehydration equipment to capture the gas during a completion, clean it and send it to
the sales line instead of flaring or venting it. This technology requires that a pipeline be laid up to
the well-pad and is now applied to many new gas wells in the United States. This technique uses
a system of piping, separators and sometimes dehydration equipment to capture the gas during
a completion, clean it and send it to the sales line instead of flaring or venting it. This technology
is now used in the majority of new wells in the United States.
Use of REC depends on the characteristics of the basin and the area it is located, but with
advanced and proper planning of field development, including gas pipeline construction and
installation and coordination with drilling, the industry is striving to reduce emissions.
• Monitoring. Responsible monitoring of all phases of operations allows for timely identification of
leaks and fast response mechanisms to reduce emissions.
• Carbon capture and storage. Carbon capture and storage technologies have the potential to
reduce life-cycle emissions from natural gas to very low levels. These technologies are not costeffective at present, but a number of pilot projects are on-going and the technology is expected
to be commercially viable after 2030 if a favourable regulatory, commercial and political
framework is in place.
…SHALE GAS OPERATIONS
…SHALE GAS OPERATIONS
– F.A.Q.s on greenhouse gases
Frequently asked questions about Green House Gases
This document provides factual information about shale gas operations and GHG
FIGURE 3: FURTHER REDUCING THE SHALE GAS GHG FOOTPRINT*
Natural gas or electricity instead
of diesel
Water pipelines
instead of trucks
Responsible
monitoring of all
phases
REC well technologies (green completions)
for example:
separator
gas
dehydrater
wellhead
sand
trap
separator
condensate
tank
wastewater
tank
*Experience shows that once
operations begin & big businesses
dedicate significant resources to
continuous improvement,
emissions will be even further
improved
CSS technologies (potentially viable post-2030)
for example:
CO2 source
4
CO2 capture &
sepration
CO2
injection
CO2
compression
CO2
storage
How can burning shale gas help regulators efforts
to reduce emissions?
On a well-to-wires basis, natural gas power plants emit around half the CO2 of coal power plants. The
relative emission rates depend on the type of gas plant and the type of coal plant being compared.
Natural gas, including shale gas, is a critical fuel for many countries to further reduce national emissions
of greenhouse gases12 (as recognised for example in the EU Energy Roadmap 205014).
…SHALE GAS OPERATIONS
…SHALE GAS OPERATIONS
– F.A.Q.s on greenhouse gases
Frequently asked questions about Green House Gases
This document provides factual information about shale gas operations and GHG
Coal-to-gas switching has been the largest contributor to the United States’ 13 and Europe’s
GHG emission reductions in the last several years. Europe achieved emission reductions of
11% reductions from 1990 levels due to fuel-switching. IHS-CERA calculated that emission
reductions of up to 58% could be achieved if all EU oil- and coal-fired power plants were converted
simultaneously to best performance combined cycle gas turbines (CCGT). In the long-term,
investment in natural gas, including shale gas, will not drive investment away from renewable
sources. Gas-fired power plants can serve both for base-load power generation and peak
consumption and are characterised by relatively low capital requirements and rapid cost recovery.
After 2030, European gas-fired power plants should be fully amortised and could serve as a flexible
back-up for variable renewables such as wind and solar or be retrofitted with Carbon Capture and
Storage (CCS) technologies, offering a long-term low-emission solution.y
FIGURE 4: GAS FROM SHALE CAN HELP THE EU REDUCE ITS EMISSIONS
On a well-to-wire basis,
natural gas power plants emit
less than 1/2 the CO2 of coal
In the long-term:
Base-load power
Peak consumption
low capital
rapid cost recovery
Emissions could be reduced by
if all EU oil- & coal-fired
power plants were converted to
best performance CCGT
Fully amortised by 2030
Flexible back-up
for renewables
CCS
Coal-to-gas switching has been
the largest contributer to
Europe’s
emission
reduction from 1990 levels
Could be retro-fitted
with CCS technologies
Shale gas can offer a long-term
low emission solution
…SHALE GAS OPERATIONS
…SHALE GAS OPERATIONS
– F.A.Q.s on greenhouse gases
Frequently asked questions about Green House Gases
This document provides factual information about shale gas operations and GHG
5
Is the current European regulatory framework
relating to high emission standards adequate?
Yes. Natural gas developments in Europe are tightly regulated activities. The current European
regulatory framework already covers emissions resulting from the extraction, processing, transportation
and combustion of shale gas with the EU Emission Trading Scheme (ETS), the Industrial Emissions
Directive and various emission performance standards.
References
Prof William Griffith et al. of Carnegie Mellon University , - Life cycle greenhouse gas emissions of Marcellus shale gas , (2011)
1.
2
. Updated Fugitive Greenhouse Gas Emissions for Natural Gas Pathways in the GREET October 25, 2013, A. Burnham, J. Han, A.
Elgowainy, and M. Wang. http://greet.es.anl.gov/publication-ch4-updates-13
3.
Draft Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2012, EPA. (open for public comment until end March 2014),
https://www.federalregister.gov/articles/2014/02/24/2014-03862/inventory-of-us-greenhouse-gas-emissions-and-sinks-1990-2012
David T. Allen1, Vincent M. Torres1, James Thomas1, David Sullivan1, Matthew Harrison2, Al Hendler2, Scott C. Herndon3,
Charles E. Kolb3, Matthew Fraser4, A. Daniel Hill5, Brian K. Lamb6, Jennifer Miskimins7, Robert F. Sawyer8, and John H.
Seinfeld9. “Measurements of Methane Emissions at Natural Gas Production Sites in the United States”. 2013.
4.
5.
EPA - Methane emissions from the natural gas industry, 1996; Kirchgessner - Estimate of methane emissions from the US natural
gas industry, (1997), Chemosphere 35: 1365–1390; Lelieveld et al. - Low methane leakage from gas pipelines, Nature 434:841–
842, (2005)
Mott MacDonald - Update on UK Electricity Generation Costs, (2011)
6.
7.
US DoE National Energy Technology Laboratory (NETL), Life Cycle Greenhouse Gas Analysis of Natural Gas Extraction &
Delivery in the United States (2011);
Deutsche Bank & WorldWatch Institute, Comparing Life-Cycle Greenhouse Gas Emissions from Natural Gas and Coal (2011)
8.
EIA 1999. Natural Gas 1998, Issues and Trends. Energy Information Administration document DOE/EIA-0560(98). http://www.eia.
gov/pub/oil_gas/natural_gas/analysis_publications/natural_gas_1998_issues_trends/pdf/it98.pdf
9.
10.
EIA 2009. Modern Shale Gas Development in the United States – A Primer. United States Energy Information Administration. April
2009. http://www.netl.doe.gov/technologies/oilgas/publications/epreports/shale_gas_primer_2009.pdf
11.
Potential Greenhouse Gas Emissions Associated with Shale Gas Extraction and Use, UK Department of Energy and Climate
Change, 2013. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/237330/MacKay_Stone_shale_
study_report_09092013.pdf
12.
Venkatesh et al. - Uncertainty in Life Cycle Greenhouse Gas Emissions from United States Natural Gas End-Uses and its Effects
on Policy, (2011); http://www.ncbi.nlm.nih.gov/pubmed/21846117
13.
International Energy Agency, Redrawing the energy climate map, 2013. http://www.worldenergyoutlook.org/media/
weowebsite/2013/energyclimatemap/RedrawingEnergyClimateMap.pdf
14.
European Commission, 2011 - Energy Roadmap, http://ec.europa.eu/energy/energy2020/roadmap/index_en.htm
ABOUT OGP
OGP represents the upstream oil & gas industry before
international organisations including the International Maritime
Organization, the United Nations Environment Programme
(UNEP), Regional Seas Conventions and other groups under
the UN umbrella. At the regional level, OGP is the industry
representative to the European Commission and Parliament
and the OSPAR Commission for the North East Atlantic.
Equally important is OGP’s role in promulgating best practices,
particularly in the areas of health, safety, the environment and
social responsibility.
Web: www.ogp.org.uk
E-mail: [email protected]
London office:
209-215 Blackfriars Road,
London SE1 8NL, UK
Tel: +44 (0)20 7633 0272
Fax: +44 (0)20 7633 2350
Brussels office:
165 Bd du Souverain,
B-1160 Brussels, Belgium
Tel: +32 (0)2 566 9150
Fax: +32 (0)2 566 9159