AGL Energy Limited · ASX:AGL
AGL Energy — Technical Presentation (September 2011)
30 slides from AGL Energy's technical presentation, Sep 14, 2011
Slide 1: Water Studies Update – AGL Upstream Gas – CSG Projects
Water Studies Update – AGL Upstream Gas – CSG Projects John Ross| 14 September 2011| Sydney
Slide 2: CSG developments: Community and regulatory issues
CSG developments: 2 Community and regulatory issues Land access, compensation and regulatory approvals Hydraulic fracturing Water resource impacts › Impact of exploration / production programs on water resources › Integrity of gas well construction › Connectivity of aquifers with deep coal seams Lon
Slide 3: Groundwater 101
3 Groundwater 101 Conceptual groundwater occurrence and flow Typical spring locations in the landscape Alluvial aquifers Shallow fractured rock aquifers CSG water bearing zones NOTE - This is a schematic only of groundwater flow through porous rocks and is not necessarily representative of any parti
Slide 4: Importance of hydrogeology in CSG developments
4 Importance of hydrogeology in CSG developments Today: › Why is NSW different to QLD? › Water resource impacts » NSW groundwater resources » Gas well construction » Connectivity – investigation methodology » Hunter conceptual model » Hunter Investigation Proofs Water levels Water quality Isot
Slide 5: NSW vs Queensland
NSW vs Queensland _ NSAGL
Slide 6: Why are NSW water issues different to QLD
6 Why are NSW water issues different to QLD It’s all about knowing the geology and hydrogeology (both regionally and locally): › Permian-Triassic basins » Older rocks » Lower permeabilities » Few (low value) aquifers » Lower water volumes › Jurassic-Cretaceous basins » Younger rocks » Higher permeab
Slide 7: AGL (NSW) PEL and PPL areas
7 AGL (NSW) PEL and PPL areas AGL knows the (coastal) Permian-Triassic Basins in NSW: › Southern Sydney Basin (Camden Gas Project) › Northern Sydney Basin (Hunter exploration program) › Gloucester Basin (Gloucester Gas Project) Compared to QLD (Surat, Galilee, Cooper), coastal NSW has: › Tighter geo
Slide 8: CSG water volumes
8 CSG water volumes Total Field Produced Water Volumes Produced water volumes are a function of: 180 › Geology (rock type and permeability) 160 › Proximity to shallow aquifers and recharge areas 140 › Degree of confinement/isolation 120 Produced waters are small for NSW ML per year (coastal) Permian
Slide 9: CSG water chemistry
9 CSG water chemistry Groundwater chemistry is a function of: Total Dissolved Solids › Geology (rock type) mg/L 40,000 › Proximity to recharge areas, recharge rates and flow 35,000 › Residence time Produced waters are typically slight to 30,000 moderate salinity: 25,000 › Camden (Na-HCO3) » 4500 to
Slide 10: Water resource impacts
10 Water resource impacts › CSG – A Sustainable Australian Energy Source 31 March 2011 EIANZ Presentation
Slide 11: Important NSW groundwater resources
11 Important NSW groundwater resources › Murray Darling Basin Salinity of Shallowest Groundwater Sources » Top 6 alluvial valleys / fans ▪ Gwydir ▪ Namoi ▪ Macquarie ▪ Lachlan ▪ Murrumbidgee ▪ Murray › Great Artesian Basin › Oxley Basin › Coastal NSW » Alluvial sediments » Sand dunes » Basalt platea
Slide 12: Water management in NSW
12 Water management in NSW › Water Act (1912) » Part V bore licences (CSG wells and monitoring bores) ▪ 137 for Camden ▪ 30 for Gloucester ▪ 10 for Hunter › Water Management Act (2000) » Water Sharing Plans ▪ Greater Metropolitan (July 2011) » Aquifer Interference Approvals › Other Policies » Buried
Slide 13: Gas production well design and construction
Gas production well design and construction 13 (1) Well design and (2) From non aquifers Sucker rod Water Supply Production tubing Aquifers Production casing Cement CSG Water Surface casing Bearing Zones Centraliser Cement Cross section of well design Typical vertical well design » Industry Briefing
Slide 14: Connectivity: Investigation methodology - Groundwater
Connectivity: Investigation methodology - 14 Groundwater AGL’s staged approach to groundwater studies involves: › Phase 1: Desktop study – review of existing data, field visit, compilation of an initial conceptual hydrogeological model and recommendations regarding future phases. › Phase 2: Detailed
Slide 15: Hunter water studies
15 Hunter water studies › CSG – A Sustainable Australian Energy Source 31 March 2011 EIANZ Presentation
Slide 16: Initial conceptual model: Recharge, discharge and flow
Initial conceptual model: 16 Recharge, discharge and flow › Hunter (Bulga- Broke) SW Regional hydrogeological conceptual model NE Catchment Boundary Catchment Boundary Rain Rain » Direct rainfall Rain recharge to the Narrabeen alluvium Group Evaporation + Transpiration (Rn) Runoff Lateral Flow Evapo
Slide 17: Permian geology
17 Permian geology Schematic of geological sequence at Broke, Hunter Valley » Industry Briefing – Water Studies » 14 September 2011 » AGL External
Slide 18: Aquifer and coal seam permeabilities
18 Aquifer and coal seam permeabilities › Many coal seams across the Sydney Basin are NOT aquifers Low High to moderate permeability aquifers (sand, gravel and highly Very low permeability zones (clay, coal seams, permeability fractured rocks) claystones, unfractured rock etc) aquifers Permeability
Slide 19: Updated conceptual model: Recharge, discharge and flow
Updated conceptual model: 19 Recharge, discharge and flow › Geology › Hydrogeology › Hunter (Broke-Bulga) › Hunter (Broke-Bulga) » Siltstones and cemented sandstones » Shallow (limited extent) alluvial common within and above the coal aquifer measures ▪ Shallow water – fresh to brackish » Claystones
Slide 20: (Lack of) connectivity proofs
20 (Lack of) connectivity proofs
Slide 21: Water level proofs
21 Water level proofs 12 Day Pumping Test › Hunter (Broke) example Broke – Alluvium ~10m » 12 day pumping test (2009) » 150 day flow test (2010) › Pumping test: » Shallowest gas well (HB02) operational » Slotted opposite Blakefield CS (~323 m) » Drawdown to 130 mbgl (Q averaged 0.17 L/s) Broke - Why
Slide 22: Water chemistry proofs
22 Water chemistry proofs › Hunter (Broke) water types Hunter (Broke) Sampling Program – September 2009 » Uppermost (alluvial) aquifer – mostly Na- Alluvial and shallow fractured Cl rock water samples » Deep coal seam water bearing zone – Na- Cl-HCO3 » Discrete differences between alluvial groundwat
Slide 23: Water chemistry proofs
23 Water chemistry proofs › Hunter (Broke) – deep coal Hunter (Broke) 2009 seams Sampling Program (HB02) » Water types remained unchanged for coal seams over both 2009 pumping test and 2010 flow testing programs Hunter (Broke) 2010 Sampling Program (HB01 and HB02) Water type » Industry Briefing – Wa
Slide 24: Isotope proofs
24 Isotope proofs › Environmental isotopes (H2 and O18) » All groundwater is derived from rainfall All shallower aquifers plot here » More depleted signatures with depth suggest older water and longer residence times › Radiogenic isotopes (H3 and Hunter (Broke) examples C14) » Tritium only present i
Slide 25: Hunter monitoring networks
25 Hunter monitoring networks › Hunter (Broke) » 9 (dedicated AGL) bore locations 6 alluvial 2 fractured rock 1 coal seam › Other Hunter » 9 (dedicated AGL) bore locations 2 alluvium 2 fractured rock 5 coal seam (3 MB and 2 VWP) › Monitoring programs » Baseline monitoring 6 months + in
Slide 26: Other monitoring networks
26 Other monitoring networks › Gloucester » 28 (dedicated AGL) bore locations 2 seepage 2 gas drainage 6 alluvial 14 fractured rock 4 coal seam » 3 surface water locations › Camden » 15 (dedicated AGL) bore locations 3 sandstone/shale (new) 12 coal seam (for WQ) › Galilee » 6 (dedicate
Slide 27: Produced water management
27 Produced water management › CSG – A Sustainable Australian Energy Source 31 March 2011 EIANZ Presentation
Slide 28: Produced water management
28 Produced water management › Think strategically but act locally Project Specific › Cost effective and sustainable solutions » Industrial and commercial » Mining Beneficial » Primary production reuses » Raw water for domestic water supply » Offsite disposal at licensed facility » Reinjection » Env
Slide 29: Conclusions
29 Conclusions Water levels, quantity and quality are directly related to the geological and hydrogeological characteristics › Different basins have different characteristics » In Sydney Basin ▪ Permian coal seams are overlain by low permeability cap rocks › Hunter hydrogeology » Groundwater in the
Slide 30: Links
30 Links › Links » Camden - http://www.agk.com.au/camden/ » Hunter - http://www.agk.com.au/hunter/ » Gloucester - http://www.agk.com.au/gloucester/ » Industry Briefing – Water Studies » 14 September 2011 » AGL External