What is Coal Seam Gas

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Dr Gavin M. Mudd
Environmental Engineering (Gavin.Mudd@monash.edu)
What the ‘Frack’?
Coal Seam Gas,
Fracking & Groundwater
DCQ-RAPAD Coal Seam Gas Forum, 21st-22nd April 2012
eng.monash.edu.au/enveng
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam
Gas & Groundwater
Courtesy:
W. Miller
21-22 April 2012 / 2
Presentation Overview
•
•
•
•
What is Coal Seam Gas (brief !)
Common Environmental Concerns
Groundwater Risks and Impacts
Need for Thorough Research &
Evidence of ‘NO HARM’
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 3
What is Coal Seam Gas ?
• Coal can often contain significant amounts
of methane – also called ‘natural gas’ –
hence the name ‘coal seam gas’ (CSG)
• CSG is a major problem for coal mining –
especially underground (CSG is the
principal cause of coal mine accidents, &
historically simply vented to the air)
• You can extract CSG before coal mining, or
even separately through bores & pipes
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 4
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 5
CSG Exploration or ‘Appraisal’ Well
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam
Gas & Groundwater
Gladstone
EIS,
21-22 April 2012 / 6
Santos, 2009
CSG Production Well
Gladstone EIS, Santos, 2009
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 7
Common Environmental Concerns
• Major environmental issues with CSG
include:
– compatibility of land use (eg. farming v CSG)
– surface water impacts (toxics, erosion, floods,
…)
– groundwater impacts – quantity & quality
– toxic pollutants released – accidents or
ongoing operations
• The extent of scientific research
documenting these risks is MINIMAL …
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 8
CSG & Water Issues
• Water WATER
WATER
18,000
240
15,000
200
CSG Water (ML)
CSG (PJ)
12,000
160
9,000
120
6,000
ML/PJ
Average: ~92 ML/PJ
3,000
0
2004
80
40
2005
Data: QDERM
0
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012
2006
2007
2008
2009
2010
2011/ 9
CSG Production (PJ/year); ML/PJ
CSG Water Produced (ML/year)
Queensland CSG
Aerial view of a CSG Water Pond
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 10
Salt storm from CSG Water Pond
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 11
Case Study: Condamine Alluvium, Qld
1.4
Daandine Condamine Alluvium Bore
-10.3
1.2
-10.4
1.0
-10.5
0.8
-10.6
0.6
-10.7
0.4
42230179 Water Level
Daandine and Kogan North Water Extraction
-10.8
0.2
Daandine Water Extraction
Water Extraction during 6 Month
Periods (ML)
Groundwater Depth from Surface (m)
-10.2
Kogan North Water Extraction
0.0
1970
1973
1976
1979
1982
1985
1988
1991
1994
1997
2000
2003
2006
2009
Groundwater Depth from surface
(m)
-15.5
1.8
42231177
42231280
Tipton West Water Extraction
-16.5
42231279
42231281
1.5
-17.5
1.2
-18.5
0.9
-19.5
0.6
-20.5
0.3
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
Courtesy: A. Brown
-21.5
1985
21-22 April 2012 / 12 0.0
1990
1995
2000
2005
2010
Annual Water Extraction (GL)
-10.9
1967
Groundwater Concerns v CSG
• Groundwater is a COMPLEX resource to
assess & manage … Australia’s track record is
widely acknowledged to be poor
• Major groundwater concerns vs CSG include:
1. Altering groundwater flow regimes, especially
deep to shallow aquifers
2. Poor quality of CSG formation waters
3. Potential for explosive buildup of methane gas
4. Dependence of rural communities & industries
on groundwater
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 13
Duke Uni. – GW, Shale Gas & CH4
• Osborn et al., 2011, Proc. Nat. Acad. Sci.
• Study of CH4 in groundwaters of shale gas
extraction and background (non-gas) areas
– for shale gas areas, showed that CH4
concentrations in groundwater are
significantly higher than background norms
– isotope fingerprinting clearly showed shale
CH4 as the source
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 14
Duke Uni. – GW, Shale Gas & CH4
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
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DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
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Need for MUCH Better Monitoring …
• CSG industry in Australia is closely related
to the use of fracking chemicals
• Yet we still do not understand the full
extent of groundwater risks – in space &
time
• Both industry & government have been too
lax in simply believing minimal impacts
• Need much greater monitoring &
transparency
• Track record is poor on both fronts …
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 17
Summary & Choices …
• CSG is a technically viable way to
produce gas, often very profitable BUT
• CSG has major issues around water
– Often poor quality water extracted with CSG
– Can be major impacts on groundwater
resources – still major uncertainty with extent
• Whether CSG should muscle out
renewable energy is yet to be seen
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 18
Acknowledgements
• John Polglase (photo’s!)
• Andrew Brown (GW graphs!)
• Many community groups in NSW and
Qld working on CSG issues
• Any questions, please contact me:
Gavin.Mudd@monash.edu
(Office 03 9905 1352 / Mobile 0419 117 494)
DCQ-RAPAD Coal Seam Gas Forum: Fracking, Coal Seam Gas & Groundwater
21-22 April 2012 / 19
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