Hydrogeological Assessment for Multi-Well Exploration and Appraisal Production Testing from Deep Coal in PEL 96 Southern Cooper Basin
Prepared for: Strike Energy Limited 16 December 2014
hydrogeologic Hydrogeologic Pty Ltd ABN 51 877 660 235 PO Box 383, Highgate South Australia 5063
hydrogeologic OVERVIEW
Strike Energy is conducting an exploration and appraisal program to evaluate the gas resource in Permian coal seams at depths up to about 2100 metres in the Weena Trough in the southern Cooper Basin about 100 km south of Moomba in South Australia. This report provides hydrogeological information to support the Environmental Impact Report (EIR) prepared under the Petroleum and Geothermal Energy Act 2000 to cover proposed multi- well production testing from deep coal in the Patchawarra Formation in Petroleum Exploration Licence (PEL) 96. Through 2013 and 2014, Strike Energy has drilled, stimulated and flowed back two wells (Klebb- 1 and Le Chiffre-1) in PEL 96, which have confirmed the presence of gas and water in the coals. Through the latter half of 2014 and into 2015, Strike is proposing to drill additional wells at the Klebb and Le Chiffre sites and then undertake multi-well production tests by pumping water for several months to initiate gas flows and test production. This small scale exploration, production testing and appraisal program proposed by Strike aims to determine the reservoir pressure at which gas production commences (the critical desorption pressure), to achieve sustained gas flows to surface and to obtain data on gas composition, reservoir fluid composition, formation water production volumes and pressure effects. Subsequent multi‐well testing will focus on well spacing and production optimisation. Hydrogeological information will also be obtained to support detailed assessments in further project stages, and to reduce uncertainties and data gaps on aquifer inter-aquifer connectivity and potential effects on the mapped GAB spring at the north-western end of Lake Blanche (contained within the PEL 96 boundary). While there is a reasonable level of broad hydrogeological knowledge in the region, notably documented in the 2012 CSIRO studies of the GAB (Eromanga Basin), there is limited specific hydrogeological data available on the underlying Cooper Basin aquifer and aquitard systems, including in the PEL 96 project area. It is also noted that Cooper Basin aquifers have very limited utility as a water resource as they are overlain by the productive aquifers of the GAB, and deep (expensive) bores would be required, not justifying the low yielding and brackish to saline water. The available knowledge base has been updated by the drilling and stimulation activities to date at Klebb-1 and Le Chiffre-1. This information has been used to undertake a hydrogeological impact assessment, with an overall conservative approach that assumes that the PEL 96 activities are occurring within the overlying GAB aquifers, rather than the deep Cooper Basin units. Strike modelling undertaken prior to the draft EIR preparation indicated water production rates may be in the order of 1500 bpd (barrels per day i.e. 240 kL/day) per well. Over the six month appraisal testing program, this would equate to approximately 44 ML per well (i.e. conservatively assuming that there would be no decline in production over this period). Assuming 10 wells (and there will likely be less than 10 wells for the appraisal program), this could conservatively amount to a volume of 440 ML over six months. This is equivalent to 2.4 ML/day, which is 4% of the water allocation plan allowance of 60 ML/day for the petroleum sector, and would amount to a 7% increase on the current production rate of about 33 ML/day (likely to decrease as water production declines during the appraisal test). Early results (to December 2014) of ongoing flow testing at Klebb-1 and Le Chiffre-1 have indicated that the wells are co-producing less water than expected when the draft EIR was developed. Klebb-1 is producing water at 200 bbl/day (32 kL/day), Le Chiffre-1 is producing 1200 bbl/day (190 kL/day), and production has shown rapid declines. The total production rate per site is demonstrably less than 1 ML/day.
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 2 hydrogeologic The appraisal testing project parameters and predicted hydrogeological impacts have been assessed under a highly conservative set of assumptions as being completely consistent with the requirements of the Far North PWA Water Allocation Plan (SAALNRM Board, 2009), including (see also Figure 18 for locations of spring exclusion zones): highly conservative conceptualisation (e.g. all water production from the Hutton Sandstone not the Patchawarra Formation), conservative aquifer parameter values (representative of a high permeability GAB aquifer) and application of the WAP- specified (de Glee) analytical modelling methodology the water balance assessment considers an appraisal program of up to 10 wells extracting at up to 0.24 ML/d per well, totalling 2.4 ML/d (or 440 ML volume over 6 months), which is 4% of the sustainable diversion limit established by the WAP of (60 ML/d), or 2% of the annual volume allocated to the petroleum sector (21.9 GL/a) the water balance assessment conservative assumptions include more wells than are actually planned and that there would be no decline in water production over this period (although this is very likely) ongoing flow testing has confirmed that actual production rates are much lower than initially predicted, amounting to less than 1 ML/day total at each site, consistent with principle 17 of the WAP the 5 km spring exclusion zone is located at a distance of 47 km from Klebb (the closest site), whereas the predicted 0.5 m drawdown is calculated (using the WAP-specified steady state method) to apply at a distance of just 40 km for an assumed extraction of 5 ML/d (which is more than twice the amount required for the appraisal test) the edge of the Southwest Springs Zone is located 41 km from Klebb, and the cumulative drawdown impact assessment is calculated as 0.5 m at 40 km, well within the 1 metre constraint (assuming 5 ML/d and steady state drawdown) sensitivity analysis with Patchawarra aquifer properties and Roseneath-Murteree aquitard properties results confirms the robust conservatism in the calculations the State border drawdown trigger (10% of the aquifer pressure head) amounts to 10 m at a distance of 90 km, whereas a maximum of 0.5 m drawdown is predicted at a distance of 40 km (i.e. compliance with the spring constraint in this case ensures compliance with the border constraint). The proposed data gathering during and following the appraisal testing will provide detailed and site-specific data for more detailed assessments in the future. A program for data gathering and future monitoring of hydrogeological parameters has been developed and will be progressively refined as the project develops, but would nominally involve: Collection of confined aquifer pressure, water production and water quality data for the Patchawarra Formation during the production testing Collection of baseline data on confined aquifer pressures and water quality in the Hutton during the drilling and appraisal program Collection of unconfined groundwater quality data Collection of detailed hydrochemistry and isotope data from GAB bores and springs GAB spring monitoring Aquifer pressure monitoring in GAB wells Water level monitoring in other non-GAB wells Possible conversion of one of the Klebb wells to a GAB monitoring well after the production testing program.
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Contents 1 INTRODUCTION ...... 7 1.1 Background on PEL 96 Program ...... 7 1.2 SEO, EIR, EAR and Hydrogeological Assessments for PEL 96 ...... 9 1.3 Multi-Well Production Testing and Appraisal ...... 9 2 Contextual Information ...... 11 2.1 Geological Setting ...... 11 2.2 Geographical Setting ...... 13 2.3 Climate ...... 14 2.4 Land Systems and Physiography ...... 15 2.4.1 Tingana Land System ...... 15 2.4.2 Collina Land System...... 15 3 Hydrology ...... 16 3.1 Regional Drainage Systems ...... 16 3.2 Strzelecki Creek and Wetland System ...... 16 4 Geology ...... 19 4.1 Cooper Basin, Eromanga Basin and Lake Eyre Basin ...... 19 4.2 Local Geological Setting (Weena Trough) ...... 21 4.3 Weena Trough Stratigraphy and Hydro-Lithology ...... 22 5 Hydrogeology ...... 24 5.1 Regional Hydrogeology ...... 24 5.2 Lake Eyre Basin ...... 27 5.3 Great Artesian Basin (GAB) ...... 27 5.3.1 Central Eromanga Basin ...... 27 5.3.2 Upper and Main Confined GAB Aquifer ...... 28 5.3.3 Hydrogeological Properties of GAB Formations ...... 30 5.3.4 GAB Groundwater Levels, Flow, Recharge and Discharge ...... 30 5.3.5 GAB Groundwater Use and Water Balance ...... 33 5.3.6 GAB Groundwater Quality ...... 34 5.3.7 GAB Groundwater Dependent Ecosystems (GDEs) ...... 35 5.4 Cooper Basin Hydrogeology ...... 36 5.5 Local Hydrogeology ...... 37 5.5.1 Weena Trough ...... 37 5.5.2 Local Hydrogeological Properties ...... 39 5.5.3 Potential Vertical Connectivity ...... 39 5.5.4 Local Groundwater Levels, Salinity, Flow, Recharge and Discharge ...... 40 5.5.5 Local Groundwater Use ...... 43 5.5.6 Local Groundwater Quality ...... 43 5.5.7 Local Groundwater Dependent Ecosystems (GDEs) ...... 44 6 Impact Assessment ...... 46 6.1 Assessment Approach ...... 46
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6.2 Far North Water Allocation Plan (WAP) ...... 46 6.3 Groundwater Management Criteria ...... 47 6.3.1 Sustainable Diversion Limits ...... 47 6.3.2 Confined Aquifer Pressure and Spring Drawdown Triggers ...... 47 6.3.3 Cumulative Drawdown Impact Assessment ...... 48 6.3.4 Drawdown Constraint at SA Border ...... 50 6.3.5 Salt Balance ...... 51 6.4 Third Party Issues ...... 51 6.5 Hydrogeological Data Gathering and Monitoring ...... 51 7 Conclusions and Recommendations ...... 53 8 References ...... 54
Tables Table 1 - Location of Klebb and Le Chiffre well sites ...... 9 Table 2 - Temperature and rainfall records for Moomba Airport (BoM station 017123) ...... 14 Table 3 - Summary of stratigraphy and hydro-lithology in central Weena Trough (Strike Energy, 2014) ...... 23 Table 4 - Summary of the regional hydrogeology (modified from Santos, 2003) ...... 25 Table 5 - Mean porosity and permeability values of GAB Formations in Central Eromanga Basin (CSIRO, 2012a) ...... 30
Figures Figure 1 - Location of Cooper and Eromanga Basins (after CSIRO, 2012b) ...... 7 Figure 2 – Location of PEL 96, Klebb-1, Le Chiffre-1, Strzelecki Creek and Lake Blanche (Strike Energy) ...... 8 Figure 3 - Location of PEL 96 and Klebb and Le Chiffre sites ...... 11 Figure 4 - South Australian Cooper-Eromanga Basin structural elements (DMITRE, 2012) ...... 12 Figure 5 - Central Eromanga region of the GAB, showing selected rivers, springs and GAB recharge areas (after CSIRO 2012c) ...... 13 Figure 6 - Regional Hydrology ...... 18 Figure 7 - Regional basins stratigraphic chart (PIRSA, 1996) ...... 20 Figure 8 - Structural elements of the southern Cooper Basin (Source: Strike, 2014) ...... 21 Figure 9 - Geographic extent of the Great Artesian Basin and selected overlying sedimentary basins (after CSIRO 2012a) ...... 24 Figure 10 - Three dimensional illustration of a slice through the GAB (after CSIRO 2012c). .... 28 Figure 11 - Stratigraphy at Klebb and Le Chiffre ...... 29 Figure 12 – Groundwater level time series - main confined GAB aquifer (CSIRO 2012c) ...... 31 Figure 13 – 3D view of GAB showing principal flow paths relatively stagnant in depocentre (after CSIRO 2012b, Figure 8.9) ...... 32 Figure 14 – Groundwater Balance of Eromanga Basin (after CSIRO, 2012b) ...... 33 Figure 15 – Salinity in the main confined GAB aquifer (a) and the upper confined GAB aquifer (b) and their equivalents (after CSIRO 2012c) ...... 34 Figure 16 – Spring complexes of the Central Eromanga region (after CSIRO 2012c)...... 36 Figure 17 - PEL 96 Conceptual Geology ...... 38 Figure 18 – Groundwater Bores and Springs ...... 41 Figure 19 - Digital Elevation Model showing water table groundwater discharge areas, after CSIRO 2012c. The red box indicates the approximate location of PEL 96...... 42 Figure 20 - Lake Blanche spring (6839-5) ...... 44 Figure 21 - de Glee calculation of steady state drawdown within 0.5 m spring constraint (after SAALNRM Board, 2009) ...... 50
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Appendices Appendix A – Groundwater Data
hydrogeologic Prepared by: Hydrogeologic Pty Ltd (ABN 51 877 660 235) PO Box 383, Highgate, 5063, South Australia email: [email protected] mobile: +61 438 983 005 Authors Hugh Middlemis (Principal Groundwater Engineer, Hydrogeologic) Revision a 10 Sept 2014 Draft report for review by Strike Energy and JBS&G Revision b 23 Sept 2014 Updated draft, more detailed impact assessment and improved figures Revision c 30 Sept 2014 Addressed reviews by Strike Energy, JBS&G, Innovative Groundwater Solutions Revision d 30 Sept 2014 Updated certain details and figures, fixed cross-references Revision e 16 Dec 2014 Addressed comments from DEWNR and IESC
This report should be cited/attributed as: Middlemis, H. (2014). Hydrogeological Assessment for Multi-Well Exploration and Appraisal Production Testing from Deep Coal in PEL96, Cooper Basin. Prepared by Hydrogeologic Pty Ltd for Strike Energy Limited and JBS&G Pty Ltd.
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1 INTRODUCTION 1.1 Background on PEL 96 Program Strike Energy is conducting an exploration and appraisal program to evaluate the gas resource in deep coal seams in the Weena Trough of the Cooper Basin, about 100 km south of Moomba in South Australia. Petroleum Exploration Licence (PEL) 96 is situated at the southern end of the Cooper Basin and within the Eromanga and Lake Eyre Basins of central and eastern Australia (indicated by small red box in Figure 1, see more detail in Figure 2). Figure 1 - Location of Cooper and Eromanga Basins (after CSIRO, 2012b)
This hydrogeological report has been prepared to support the Environmental Impact Report (EIR) prepared under the Petroleum and Geothermal Energy Act 2000 to cover multi-well production testing from deep coal in the Patchawarra Formation in PEL 96 (Figure 2). Through 2013 and 2014, Strike Energy has drilled, stimulated and flowed back two wells (Klebb-1 and Le Chiffre-1) in PEL 96 (Figure 2). These activities are part of a program to confirm the presence and prospectivity of the Permian coals at depths up to about 2100 metres in the Weena Trough. Results of this program to date have indicated the presence of gas and water in the coals. Through the latter half of 2014 and into 2015, Strike is proposing to drill several additional wells at the Klebb and Le Chiffre sites and then undertake multi-well production tests, which will involve pumping water for several months to initiate gas flows and test production.
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Figure 2 – Location of PEL 96, Klebb-1, Le Chiffre-1, Strzelecki Creek and Lake Blanche (Strike Energy)
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While there is a reasonable level of broad hydrogeological knowledge in the region, notably documented in the 2012 CSIRO studies of the GAB (cited herein), there is limited specific hydrogeological data available on Cooper Basin aquifer and aquitard systems in the PEL 96 project area (Figure 2). The small scale exploration, production testing and appraisal program proposed by Strike will improve the hydrogeological information and reduce uncertainties and data gaps on aquifer inter-connectivity and potential drawdown at GAB springs to the south-west at Lake Blanche. The proposed data gathering during and following the appraisal testing will provide detailed and site-specific data for more detailed assessments in the future. 1.2 SEO, EIR, EAR and Hydrogeological Assessments for PEL 96 All regulated activities under the Petroleum and Geothermal Energy Act 2000, including drilling, fracture stimulation and production testing activities must be covered by an approved Statement of Environmental Objectives (SEO). All wells are drilled, cased and cemented in accordance with the requirements of the Cooper Basin Drilling and Well Operations SEO (Santos 2009). Strike has completed the PEL 96 stimulation activities to date under the existing Beach Energy SEO for fracture stimulation in the Nappamerri Trough (Beach, 2012), combined with a specific Environmental Assessment Report (EAR) prepared for Strike by RPS (2014a). A new SEO to cover the exploration and appraisal multi-well production testing is being developed in parallel with the new Environmental Impact Report (Strike, 2014). This desktop hydrogeological study is based on the previous hydrogeological report (RPS, 2014b) that was prepared to support the previous EAR that covered activities to date (RPS, 2014a). The previous EAR (RPS, 2014a) was based on the available geology and hydrogeology information and limited site-specific data. The available knowledge base has been updated since that time by including data from the drilling and stimulation activities to date at Klebb-1 and Le Chiffre-1. This information has been used to undertake a more detailed hydrogeological impact assessment (this report). This report version E (Dec 2014) includes updates to address comments from government agencies on draft version D. 1.3 Multi-Well Production Testing and Appraisal The objective of production testing at the Klebb site is to: determine the reservoir pressure at which gas production commences (the critical desorption pressure) achieve sustained gas flows to surface obtain data on gas composition, reservoir fluid composition, formation water production volumes and pressure effects. Subsequent multi‐well testing including at the Le Chiffre site will also investigate well spacing and production optimisation. Hydrogeological information will also be gathered so that it can be used for detailed assessment of any further project stages. The multi-well production testing will be undertaken at the Klebb-1 and Le Chiffre-1 sites in the Weena Trough in PEL 96 (see Figure 2 and Table 1). Table 1 - Location of Klebb and Le Chiffre well sites Name Easting Northing Klebb-1 400563 6789507 Le Chiffre-1 407750 6786090
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The initial production test is planned to be undertaken at the Klebb site and will initially involve two additional wells to about 2100 m depth, plus the Klebb-1 well. The requirement for subsequent wells at the Klebb site will be assessed once initial production test results are obtained. Since initial flow-back information suggests that the Le Chiffre-1 well has greater productivity than the Klebb-1 well, it is possible that production testing at the Le Chiffre site may involve more than two additional wells. Well spacing will be in the order of 200 m for the initial Klebb testing but may be increased in subsequent test locations, and notably at the Le Chiffre site, where the multi‐well testing will focus on well spacing and production optimisation. The new wells will be drilled to about 2100 m depth and will be completed for production, with pumps installed. The production testing will involve pumping from the multiple wells to draw down water in the target Patchawarra coals and initiate gas production. Water will be directed to ponds for storage and evaporation. Once gas flow commences, it will be monitored to establish production and reservoir parameters, with the produced gas sent to a flare. All wells will be drilled, cased and cemented in accordance with the requirements of the Cooper Basin Drilling and Well Operations Statement of Environmental Objectives (Santos 2009). Given the results obtained to date from Klebb-1 and Le Chiffre-1, fracture stimulation is not expected to be undertaken at these additional wells due to the natural permeability of the coals. If it is required to be undertaken, any fracture stimulation would be small scale and designed to be confined within the target coal seam, similar to the fracture stimulation undertaken at Klebb-1 and Le Chiffre-1. Any fracture stimulation required would be undertaken under the existing SEO (Beach 2012b). Strike’s modelling in early 2014 indicated water production rates may be in the order of 1500 bpd (barrels per day i.e. 240 kL/day) per well. Over the six month appraisal testing program, this equates to about 44 ML per well (i.e. conservatively assuming that there would be no decline in production over this period, but acknowledging that this is very likely). The total (10 well) maximum production rate is predicted to be equivalent to 2.4 ML/day or 440 ML over six months. Early results (to December 2014) of ongoing flow testing at Klebb-1 and Le Chiffre-1 have indicated that the wells are co-producing less water than expected when the draft EIR was developed. Klebb-1 is producing water at 200 bbl/day (32 kL/day), Le Chiffre-1 is producing 1200 bbl/day (190 kL/day), and production has shown rapid declines. The total production rate per site is demonstrably less than 1 ML/day, consistent with principle 17 of the Far North Water Allocation Plan (WAP). This lends a further degree of conservatism to the EIR assessment, which demonstrates that, even using extremely conservative assumptions (e.g. that the water is being extracted directly from the GAB), potential impacts are not significant and are well within the sustainable extraction settings and constraints established in the Far North WAP.
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 10 hydrogeologic 2 CONTEXTUAL INFORMATION 2.1 Geological Setting The Cooper Basin and the overlying Eromanga Basin are located in north-east South Australia and south-west Queensland (Figure 1). The region forms Australia’s largest onshore oil and gas development and has been a major supplier of gas and a significant supplier of oil and LPG to south-eastern Australia for over forty years. Strike holds Petroleum Exploration Licence (PEL) 96, located in the southern portion of the Cooper and Eromanga Basins, roughly 100 km south of Moomba (Figure 3). The licence encompasses the Weena Trough, which comprises a syncline or graben structure up to about 2200 m deep, with a Permian sequence of up to about 750 metres thickness (Figure 4). The target Weena Trough is indicated by orange shading in Figure 3 within the extent of the Cooper Basin (olive shading; after Strike Energy, 2013). Figure 3 - Location of PEL 96 and Klebb and Le Chiffre sites
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Figure 4 - South Australian Cooper-Eromanga Basin structural elements (DMITRE, 2012)
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The PEL 96 permit is underexplored. Historical drilling in the permit area failed to discover commercial hydrocarbons, although that exploration targeted stratigraphic highs where conventional accumulations are more likely to occur. Recent drilling activities in the Basin, in PEL 96 in the Weena Trough, and in the Milpera Trough to the north (PEL 94 and PEL 95, Figure 2) have focused on the deeper part of these troughs, and also the Battunga Trough (Figure 4), rather than the structural highs where drilling has traditionally focused. Coal in the central, deeper part of these troughs appears to be better developed than shallower coals in the structural highs. 2.2 Geographical Setting The licence area lies within the Strzelecki Desert (red box in Figure 5), which comprises one of the largest linear sand dune environments in the world (these can be seen in Figure 2). The dominant surface water feature in the region is the Cooper Creek, which originates in catchments in south-west Queensland and drains into the Lake Eyre Basin (Figure 5). The Strzelecki Creek is an overflow of the Cooper Creek and runs off the main channel just west of the South Australian border, flowing southward into the Lake Frome catchment. Figure 5 - Central Eromanga region of the GAB, showing selected rivers, springs and GAB recharge areas (after CSIRO 2012c)
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The Strzelecki Creek is part of an ephemeral wetland system that extends 200 km south from Cooper Creek to Lake Blanche at the centre of a string of interconnected ephemeral lakes, including Lake Gregory (north-west of Lake Blanche) and Lake Callabonna (south-east of Lake Blanche), with the predominantly dry salt pan of Lake Frome further south. Lake Blanche is contained within the PEL 96 boundary; it is about 20 km wide and 40 km long. Lake Blanche is an ephemeral freshwater lake that becomes saline as it dries out, and it has a mapped GAB spring at its north-western end (Figure 2). Away from the Strzelecki Creek floodplain, the dunefields are extremely arid, lacking any permanent surface water with significant drainage lines generally absent. 2.3 Climate The region has an arid climate, with low rainfall and high evaporation. A summary of climate records for Moomba Airport, which has the most complete data set nearest to the site (roughly 100 km north), is provided in Table 2. Seasons are generally characterised by hot dry summers and mild dry winters. Rainfall in the area is highly erratic, with no distinct seasonal rainfall pattern. Annual average rainfall is about 200 mm and this amount can be recorded in a single rainfall event due to localised, intense rainfalls associated with thunderstorm activity. Temperatures follow a seasonal trend, with cool winters and hot summers. The maximum recorded temperature at Moomba Airport is 47.3°C and the minimum is -0.5°C (BoM 2014). Table 2 - Temperature and rainfall records for Moomba Airport (BoM station 017123)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual Average Daily Max 39 37 34 29 24 20 20 23 28 31 34 36 29 Temp (C) Average Daily Min 25 24 20 16 11 7 6 8 12 16 19 22 16 Temp (C) Average Monthly 13 33 24 7 10 10 16 5 14 10 22 14 177 Rainfall (mm)
Evaporation is a specific term applied in relation to evaporation from open-water surfaces, and is usually based on pan evaporation data. The closest pan evaporation site is at Moomba (BoM station 017096; about 100 km north of the site), with recorded average pan evaporation of 9.7 mm per day, or about 3500 mm per year. The national distribution map of pan evaporation indicates an average annual rate of 3200 mm (BoM, 2014) in the area of PEL 96. When estimating evaporation from facilities such as water management ponds, the pan evaporation rates is often used, usually with a reduction factor applied (to account for pan measurement issues). Evapotranspiration (ET) is a collective term (i.e. distinct from pan evaporation) for the transfer of water (vapour) to the atmosphere from vegetated and/or un-vegetated land surfaces (BoM, 2001). ET is a large component of the water balance of a catchment, with around 90% of the precipitation that falls on the Australian continent being returned through ET to the atmosphere (BoM, 2001). ET is affected by climate, availability of water and vegetation.
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Evapotranspiration has been mapped by BoM across Australia, with the following definitions applying (BoM, 2001), in very simple terms: Actual ET is the rate of evapotranspiration expected broadly across the landscape (e.g. where the water available is subject to constraints, typically by the rainfall). At the project site, the average annual actual ET is mapped at around 100 mm. Areal Potential ET is the rate of evapotranspiration that is not constrained by water availability (e.g. would apply to areas with a very shallow water table). At the project site, the average annual areal potential ET is mapped at around 1300 mm. 2.4 Land Systems and Physiography The area hosting PEL 96 is characterised by the dunefields of the Tingana land system (formerly part of the Strzelecki land system). A portion of PEL 96 is also mapped as the Collina land system, which is a transitional land system between the large ephemeral lakes (Lake Callabonna, Lake Blanche and Lake Gregory) and the extensive dunefields in the region. However, landscape and vegetation associations in the PEL 96 locality are more typical of the Tingana land system. The characteristics of the Tingana and Collina land systems are provided below as described in the Marree Soil Conservation Board District Plan (Marree SCB 2004). 2.4.1 Tingana Land System The dunefields of Tingana land system comprise long parallel sand ridges with semi-mobile crests, sandy and clayey inter-dunes, and numerous claypans and internal soakages. Dunes are red siliceous sands, deep, with semi-mobile crests and relatively stable slopes. Lower slopes and narrower inter-dunes are clayey sands to red sandy clay loams. Narrow inter-dunes (<300 m wide) are characteristically massive (non-cracking) red sandy clay loam, usually with a shallow veneer of loamy sand to a maximum of 20 cm depth. Wider inter-dunes, (up to 1 km between crests), have red self-mulching cracking clay soils with frequent areas of claypan and non-cracking massive red earths. Claypan swamps may be present in any inter-dune zone but are largest and most frequent in the wider inter-dunes. Margins of swamps have massive red earths with little vegetation, with brown or grey cracking self-mulching clays in lower parts of the swamp. Grey clays occur at the terminus of drainage. Claypan swamps diminish in size and importance to the south. While claypans remain frequent, the development of the productive grey cracking clays of swamp centres is limited. Low limestone or kopi rises are present in some inter- dunes as a minor component. Surface soils remain sandy loams, becoming calcareous at depth. 2.4.2 Collina Land System The Collina land system consists of a highly eroded and saline dunefield of truncated parabolic dunes adjacent and north of the Lake Callabonna-Blanche-Gregory complex with predominantly nitre bush dunes with broad saline flats and small plains and many small saline depressions.
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3 HYDROLOGY 3.1 Regional Drainage Systems The surface water system in the region is dominated by the Cooper Creek, which originates in catchments located in south-west Queensland and drains south-westerly direction into the Lake Eyre Basin (Figure 6). Strzelecki Creek is an overflow of the Cooper Creek. It breaks away from the main Cooper channel near Innamincka, just west of the South Australian border, and flows southward into the Lake Frome catchment. The region is covered by the Simpson–Strzelecki Dunefields (DEH, 2009), which provide drainage features in the Cooper Creek and Strzelecki Creek systems that consist of complexes of waterholes, braided streams, channels, floodplains and ephemeral saline lakes which vary considerably depending on frequency and intensity of flooding (Figure 6). 3.2 Strzelecki Creek and Wetland System The Strzelecki Creek is associated with the ephemeral Strzelecki Creek wetland system, which extends 200 km south from the Cooper Creek divergence to Lake Blanche (Figure 6). Lake Blanche is about 20 km wide and 40 km long and is contained within the PEL 96 boundary. The north-eastern margin of Lake Blanche is located about 30 km from the Klebb and Le Chiffre sites, while the south-western margin is about 50 km distant. There is a mapped spring about 50 km from Klebb-1 on the western margin of Lake Blanche. The Strzelecki Creek system is a complex, low gradient, low topography, poorly coordinated, extensive and extremely variable river-floodplain system. It consists of channels, temporary waterholes, swampy flats, sandy plains and low sand dunes, and is recognised as a nationally important ephemeral wetland (DEH 2009). Locally to the project area, the Strzelecki Creek runs between the Klebb and Le Chiffre well sites at distances of about 3-5 km from each site (the creek meanders in this area), but the sites are isolated from direct interaction with the creek. These issues are discussed in detail in the EIR (Strike, 2014), along with the site environmental management procedures. Lake Blanche is linked to Lake Callabonna further to the south-east (Figure 6). Both lakes can also receive inflows from the Flinders Ranges. Another lake associated with the wetland system is Lake Gregory, located about 20 km to the north-west of Lake Blanche. Mapping indicates that Lake Gregory is not directly linked to Lake Blanche nor the Cooper Creek nor Strzelecki Creek, and presumably receives most of its inflow from the Flinders Ranges. When flow occurs down the length of Strzelecki Creek, it feeds into Lake Blanche, with very high flows permitting water to flow into Lake Callabonna about 20 km further south-east. About 40 km further south from Lake Callabonna is Lake Frome, which is usually a dry salt pan unless it receives exceptional overflow from Lake Callabonna or water from heavy rainfall in the Flinders Ranges (DEH, 2009). Streamflows in this region are unregulated and highly variable (Puckridge et al., 1998; Knighton and Nanson, 2001). Rivers and creeks are intermittent to ephemeral, with short periods of flow following rain, and long periods with no flow at all. They transform from dry channels with occasional waterholes in dry times to slow moving 'inland seas' up to several kilometres wide during floods (DEH, 2009; McMahon et al, 2005). Strzelecki Creek is predominantly dry; it can receive some localised inflow from heavy rainfall events but generally only flows during large Cooper Creek floods. Some flow in the Cooper Creek occurs almost every year (DEH 2008), however flows large enough to initiate flow in Strzelecki Creek occur relatively infrequently. Flows large enough to result in flow into Strzelecki Creek (but not as far as Lake Blanche) have been estimated as occurring (on
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 16 hydrogeologic average) every ten years, while flows large enough to fill Lake Blanche have been estimated to have a 20 year frequency (Puckridge et al, 1998). The Strzelecki Creek wetland system supports numerous aquatic and terrestrial species and is recognised nationally and internationally as a wetland of significance due to its species richness and abundance. Maintaining water flows, including overflows from the Cooper Creek system, is essential to conserving the unique vegetation communities and fauna associated with the Strzelecki system (DEH, 2009). The Strzelecki system “represents an extreme example of ecological processes and adaptations within arid river systems in that it receives flows from the Cooper Creek system only under extreme flood conditions” (DEH, 2009). Within the dune system, surface water is ephemeral and typically restricted to individual claypans and swales within the inter-dune corridors. Water ponds in swales and may remain for a few days to a few weeks or more, depending on the volumes of drainage from the rainfall event and rates of evaporation and infiltration. Significant local rainfall events can result in shallow inundation of floodplains, inter-dune claypans and other areas of poorly drained impermeable soil, which can persist for days to weeks or longer. A network of small, defined drainage lines from the Tibooburra and Barrier Ranges in New South Wales flow west toward Lake Callabonna and Lake Frome through the southern Strzelecki Desert, but runoff is generally insufficient to reach the distant lakes except after larger rainfall events (DEH, 2009).
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 17 235000 285000 335000 385000 435000 485000 535000 COOBER PEDY INNAMINCKA ! !
ROXBY DOWNS !
BROKEN HILL CEDUNA ! ! PORT AUGUSTA ! WHYALLA !
RENMARK ! ! 6908000 6908000 PORT LINCOLN ! ADELAIDE MILDURA ! SWAN HILL ! MOOMBA QUEENSLAND !
LEGEND
! Locality
6858000 6858000 !( Drilling Site K
E E A@ R GAB Spring C MERTY MERTY I ! K Watercourse C EK E CO RE L Track OPER C E Z R T Main Highway S Gas Pipeline
6808000 6808000 Oil Pipeline A@ LAKE GREGORY State Boundary KLEBB 1!( !( LE CHIFFRE 1 Petroleum Exploration Licence PEL 96
Patchawarra (Vm3 coal)
A@ PEL 96 Inland Water LAKE BLANCHE National Park 6758000 6758000
Recreational Reserve
SOUTH AUSTRALIA SOUTH NEW SOUTH WALES SOUTH NEW
A@ A@A@ A@A@ A@ ± 15 0 15 30 MARREE ! Kilometres A@A@A@ A@ A@ A@ A@ A@ APPROX SCALE 1:1,750,000 @ A4 A@ A@ @A@A@AA@A@A@A@A@ LAKE CALLABONNA A@A@A@ AA@ GDA 1994 MGA Zone 54 6708000 6708000 WITCHELINA A@ !
DATA SOURCES RPS Geoscience Australia SARIG FARINA !
Disclaimer: While all reasonable care has been taken to ensure the information contained on this map is up to date and accurate, no guarantee is given that the information portrayed is free from error or omission. Please verify the accuracy of all information prior to use. 6658000 6658000 LYNDHURST ARKAROOLA VILLAGE ! ! A@ FIGURE 6 LAKE FROME Regional Hydrology 235000 LEIGH CREEK285000 335000 385000 A@ 435000 485000 535000 ! A@ ! A@A@ ! hydrogeologic
4 GEOLOGY
This section provides a broad regional geological context along with more detail on the local geology of the Weena Trough and PEL 96 area based on information provided by Strike Energy including seismic interpretation and from the drilling and testing to date at Klebb and Le Chiffre, published reports, and information from the State government’s SARIG database (https://sarig.pir.sa.gov.au/Map). 4.1 Cooper Basin, Eromanga Basin and Lake Eyre Basin PEL 96 is situated within the Cooper, Eromanga and Lake Eyre Basins of central and eastern Australia (Figure 1 and Figure 2). The stratigraphy of the Cooper and Eromanga Basins is shown in Figure 7. The Cooper Basin is a north-east to south-west trending basin that extends over an area of about 153,000 km2 in north-east South Australia and south-west Queensland (Stanmore, 1989). The Permian age Cooper Basin is underlain by pre-Permian basement and overlain (unconformably) by the Mesozoic age Eromanga Basin. The Cooper Basin sediments are characterised by fluvial, deltaic, and swamp deposits that include some coal measures (Thornton, 1979). The sediments contain petroleum reservoirs (mainly gas) and some aquifers, with sediment accumulations exceeding 1,500 m thickness in some places. In the project area, the Cooper Basin sediments are typically 600-750 m thick, to depths up to about 2200 m. The Eromanga Basin unconformably overlies the Cooper Basin, and extends over a much larger area of around one million square kilometres, covering parts of Queensland, New South Wales, South Australia and the south-east corner of the Northern Territory (Figure 1). The Mesozoic age Eromanga Basin sediments were deposited under fluvial (river), lacustrine (lake) and later shallow-marine conditions, and are broadly continuous across the Basin (Vine, 1976). These sediments are gently folded in some areas and contain a succession of geographically extensive sandstone formations that serve as oil reservoirs and also as regional aquifers of the Great Artesian Basin. The Eromanga Basin sediments in the PEL 96 area are typically around 750 m thick, to depths of 1300-1400 m. Consultation with DEWNR in December 2014 identified that the Eromanga Basin sediments have been recently re- mapped. Although this new data was not available in time for this report version E (Dec 2014), the information will be utilised in ongoing investigations, including to update the conceptual hydrogeological understanding, 3D block models and cross-sections. The near-surface sediments of the Lake Eyre Basin consist generally of floodplains, wetlands, tablelands, gibbers and salt pans. At depth (but above the Eromanga Basin), Tertiary age units include the Yandruwantha Sand (medium to coarse grained sand), the Namba Formation (deltaic and lacustrine clay, silt and sand), and the Eyre Formation (sandstone and shale). The thickness of Lake Eyre Basin sediments in the project area is about 250 m, with about 400-450 m thickness of Winton Formation below that and above the Eromanga Basin. The tectonic history of the Cooper and Eromanga Basins is complex and has been characterised by several periods of rift-related subsidence and compressional uplift and erosion. This history has resulted in the Cooper Basin being subdivided into a number of large scale sub-troughs separated by fault bounded ridges (Figure 4, Figure 8). The historical evolution of the Cooper and Eromanga Basins is discussed by Kuang (1985), Finlayson et al (1988), Gallagher (1988), Hunt et al (1989) and Stanmore (1989). The PEL 96 sites target the Weena Trough on the southern margins of the Cooper Basin (Figure 2). The Weena Trough is broadly analogous with the Milpera Trough, separated from it by the Milpera Ridge (Figure 4, Figure 8).
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Figure 7 - Regional basins stratigraphic chart (PIRSA, 1996)
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Figure 8 - Structural elements of the southern Cooper Basin (Source: Strike, 2014)
4.2 Local Geological Setting (Weena Trough) The Weena Trough lies in the most southern part of the Cooper Basin in South Australia and is separated from the rest of the basin by the Milpera Ridge and Tinga Tingana Ridge to the north and north-east (Figure 8). The Patchawarra coals (in particular the Vu coal) are the primary target of the proposed multi-well production test. The target coals occur at depths of about 1900-2100 m in the Weena Trough depocentre. The Weena Trough can be divided into two distinct portions, bounded laterally and underlain by pre-Permian basement: the main Weena Trough is aligned south-west to north-east and is roughly V shaped with the southern tip of the V being shallowest the western portion is bound at the north by an east-west trending normal fault and can be defined as a half graben. The Weena Trough (Cooper Basin) underwent sedimentation from Late Carboniferous to Early Triassic times. The orientation of the Weena Trough is postulated to be due to the glacial reactivation of underlying lineaments in the Cooper Basin. The structural evolution comprised an early extensional regime and three subsequent compressional stages, each separated by gentle subsidence. The extensional regime was active during the deposition of the Merrimelia Formation and Lower Patchawarra Formation and is witnessed by growth mapped on the northern and southern bounding structural features of the Weena Trough. The first compressional stage occurred during the deposition of the Middle Patchawarra Formation. The second compression occurred after the regional deposition of the Daralingie Formation, which whilst not present in the Weena Trough, resulted in the Tinga Tingana reverse fault and Daralingie Unconformity. The final compressional stage occurred at the
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 21 hydrogeologic end of sedimentation in the Cooper Basin in Mid Triassic times, as indicated by the unconformity at the top of the Cooper Basin (Simon, 2000). Seismic data is limited in the Weena Trough however there are a number of 2D lines mostly from the 1960s and 1980s, which were used to delineate major structural features and infer coal development. In 2012, the PEL 94 Davenport-1 well (Figure 2) was drilled in the depocentre of the Milpera Trough (immediately to the north of the Weena Trough) and encountered the thickest coal intersection seen up until that time in the Cooper Basin. Strike believed the Milpera Trough to be analogous to the Weena Trough, and this was confirmed when Le Chiffre-1 and Klebb-1 both encountered thick (600-750 m) and almost complete Permian sections in the Weena Trough depocentre, with total coal sequences of the order of 100 m, greater than that found at Davenport-1. The Permian section in the Weena Trough occurs at least 1000 m shallower than in the Nappamerri and Patchawarra Troughs of the main Cooper Basin (see Figure 4). 4.3 Weena Trough Stratigraphy and Hydro-Lithology A summary of the stratigraphy and hydro-lithology intersected in the Weena Trough is shown in Table 3. Table 3 shows that the Triassic Nappamerri Group (regional aquitard/seal) was not identified during the drilling of Klebb-1 and Le Chiffre-1 and recent age dating by Strike confirmed its absence, presumably due to a combination of deposition and erosion processes at the Jurassic unconformity. However, the Permian age Roseneath Shale and Murteree Shale were identified in the depocentre, with thicknesses of 16-33 m. Seismic data indicates that these Permian seal units extend across the bulk of the Weena Trough, but it is not confirmed exactly how far (i.e. it is possible but not confirmed that these aquitard units may not extend to the extremities of the main south-west trough and the western half-graben). In these south-western and western extremities, the Permian sandstone-siltstone formations could be directly overlain by the basal Jurassic Hutton Sandstone. In other words, in some localised areas in this southern Cooper Basin region there is a possible absence of intervening aquitard units (Roseneath and/or Murteree), and direct connection between GAB and Cooper Basin units (Dubsky and McPhail, 2001). For example, the Tinga Tingana-1 well is located 7 km north-east of the Le Chiffre-1, on a structural high on the eastern margins of the Weena Trough. At this location, the Hutton Sandstone directly/unconformably overlies the Patchawarra Formation. The Patchawarra DST salinity in 1968 was measured at 2338 mg/L TDS in this well, which is interpreted as due to downward leakage from the typically lower salinity GAB aquifers (Dubsky and McPhail, 2001). This is similarly apparent with Cherri-1 located about 17 km south-east of Le Chiffre, which is logged as Algebuckina Sandstone directly over Epsilon Formation. Cherri-1 had a Patchawarra DST salinity measurement in 1970 of 2050 mg/L Dubsky and McPhail, 2001). These wells are located within PEL 96 - see Figure 2 for locations. Dubsky and McPhail (2001) suggested that "As formations become hydraulically connected both vertically and areally, their hydrodynamic and hydrochemical properties tend to become similar. An areal example is the interconnected Algebuckina Sandstone. Units are separated vertically but connected areally, and hence pressures and salinities are quite similar. Cooper Basin is vertically connected to the overlying Eromanga in the southern areas, such that salinity and pressure near Eromanga values." Until further data can be obtained on the detailed structure and properties, particularly in the western areas of the Weena Trough (i.e. in the vicinity of the GAB spring at the north- western end of Lake Blanche), it is considered prudent that the hydrogeological impact assessment of the appraisal testing program (refer to Section 6) conservatively assume production directly from the Hutton Sandstone (the deepest GAB aquifer).
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Table 3 - Summary of stratigraphy and hydro-lithology in central Weena Trough (Strike Energy, 2014) Formation Weena Trough thickness (m) (Eromanga Basin Classification Lithologies Cooper Basin) Klebb-1 Le Chiffre-1
Eyre Basin sediments Mainly Quaternary sediments (Namba Formation, Aquifer/Aquitard 285 246 and Tertiary sands Eyre Formation) siltstone, sandstone, minor Winton Formation Aquifer 340 400 claystone, coal Mackunda Formation Aquifer siltstone, sandstone 132 55 Oodnadatta Formation Aquitard siltstone 138 158 Coorikiana Formation Minor Aquifer siltstone, minor limestone 14 7 Bulldog Shale Aquitard siltstone, minor sandstone 194 224 Formation siltstone, fine grained Cadna-owie Formation Aquifer 45 53 sandstone Murta Formation Aquitard siltstone, sandstone 42 38 McKinlay member Minor Aquifer sandstone, siltstone 17 17 Namur Sandstone Minor Aquifer sandstone, siltstone 182 174 siltstone, sandstone, Birkhead Formation Minor Aquitard 12 5 mudstone Hutton Sandstone Aquifer sandstone, siltstone 46 54 Nappamerri Group Aquitard siltstone, sandstone 0 0 sandstone, siltstone, Toolachee Formation Reservoir 147 104 mudstone, coal Roseneath Shale Aquitard mudstone, siltstone 17 16 Epsilon Formation sandstone, siltstone, Reservoir 150 140 (multiple sands) mudstone, coal Murteree Shale Aquitard mudstone, siltstone 26 33 Patchawarra Fm. sandstone, siltstone, 331 305 Reservoir (including coals) mudstone, coal (89) (66) Tirrawarra / sandstone, siltstone, Potential reservoir 69 24 Merrimelia Formation mudstone Source: Adapted from RPS (2014b), which was adapted from Beach (2012a), with consideration of the Strike post drilling geological review.
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 23 hydrogeologic 5 HYDROGEOLOGY 5.1 Regional Hydrogeology The Great Artesian Basin (GAB) dominates the regional context. The GAB is one of the largest multi-layer aquifer systems in the world. It underlies one fifth of Australia (Figure 9) and comprises Jurassic and Cretaceous sediments of three large sedimentary basins, the Eromanga, Carpentaria and Surat Basins, of which the (geological) Eromanga Basin is by far the largest. In the project area (red box in Figure 9), the Eromanga Basin is overlain by the Lake Eyre Basin and is underlain by the Cooper Basin. A summary of the regional hydrogeology is provided in Table 4 (some units identified by Strike drilling as absent in the Weena Trough are not included; e.g. Adori, Westbourne). Figure 9 - Geographic extent of the Great Artesian Basin and selected overlying sedimentary basins (after CSIRO 2012a)
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Table 4 - Summary of the regional hydrogeology (modified from Santos, 2003)
Basin Reservoir / Aquifer Use Extent Salinity Pressure System Permeability Eyre Basin Limited use aquifer Tertiary-Quaternary aquifer system. Eyre Formation for petroleum Basin wide Unclear, typically high (>9000 mg/L) Low-Moderate (Quaternary- exploration (rig water) Unknown pressure, probably less than GAB Tertiary) Part of upper confined GAB aquifer. Unknown Winton Formation Limited use aquifer Basin wide As above Low-Moderate pressure, probably less than GAB Part of upper confined GAB aquifer. Known to Mackunda Formation Limited use aquifer Basin wide Unclear, typically high (>9000 mg/L) be less pressure than GAB (Della 20 Low-Moderate evidence) Minor GAB Aquifer above Bulldog Shale. Restricted to marginal Generally low Coorikiana Minor Aquifer and Unclear, typically high (>9000 mg/L) southern and central One data point indicates pressure apparently but local areas Sandstone Potential Reservoir dataset, may be high or low areas of Basin less than GAB. Unclear if in communication up to moderate with GAB in Cooper area. Eromanga Bulldog Shale Major Aquitard Basin wide High (>10,000 mg/L (Appendix A) Main GAB aquitard unit Very Low Basin Stock watering (upper Cadna-owie Main confined GAB Aquifer (Cretaceous). Low-Moderate unit of main confined Basin wide 500-1500 mg/L (generally) (Cretaceous- Formation Potential for artesian conditions. (avge = 100 mD) GAB aquifer) Jurassic. Part of main confined GAB aquifer (data on Basin wide, but sands Limited data (2000-3000 mg/L) for Low (multiple Murta Formation Minor Aquitard pressures variable and source not verifiable, Great may be limited in extent Murta sands milliDarcy) Artesian possible problem with mixing McKinlay data). Basin Namur Sandstone Minor aquifer and Part of main confined GAB aquifer. May have Low (multiple (GAB)) (includes McKinlay Basin wide 2000-3000 mg/L (generally) reservoir local depleted zones milliDarcy) member) Minor Aquifer- Birkhead Formation Part of main confined GAB aquifer. May have Highly variable Aquitard. Potential Basin wide 3000-4000 mg/L (generally) (multiple sands) local depleted zones (moderate) Reservoir Stock watering (lower Main confined GAB aquifer (Cretaceous). 1000-3000 mg/L (generally) Moderate Hutton Sandstone unit of main confined Basin wide Algebuckina Sandstone equivalent. May have 1000-1800 mg/L (southern Cooper) (avge = 130 mD) GAB aquifer) local depleted zones Note: Selected salinity values in table adjusted from Santos (2003), to be more consistent with Dubsky and McPhail (2001), including to indicate “typical or average” salinity, as well to be consistent with data obtained during PEL 96 investigations.
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Table 4 (continued) - Summary of the regional hydrogeology (modified from Santos, 2003)
Basin Reservoir/ Aquifer Use Extent Salinity Pressure System Permeability 3000-7000 mg/L. Local variations Generally Basin-wide, In general: may be same or greater or less Nappamerri Group appear to depend on connection with Major Aquitard sands of local extent. pressure than GAB. May have local depleted Very Low (multiple sands) GAB. Absent at Klebb-1 and Le Absent in Weena Trough. zones. Absent at Klebb-1 and Le Chiffre-1. Chiffre-1. Potential for very high pressures in centre of Basin. May be same or greater or less than Generally Basin wide, but 4000 to 13,000 mg/L apparently GAB generally, and may have local depleted Highly variable, Toolachee Formation sands of local extent. depending on connection with GAB. Reservoir zones. In southern Cooper Basin, expect likely low (multiple sands) Complex inter- Data set combined with Daralingie; similar pressures to GAB due to proximity of permeability connections across Basin average about 5000. overlying Hutton Sandstone (Dubsky & McPhail, 2001). Roseneath Shale Aquitard Generally Basin-wide Uncertain, likely high As above Very Low Generally Basin wide, but As above, but also influenced by regional seal Cooper Limited dataset, 5000 to10,000 mg/L Highly variable, Epsilon Formation sands of local extent. units of Roseneath (overlying) and Murteree Reservoir apparently depending on connection likely low (multiple sands) Complex inter- (underlying). See also comment below re (Triassic- with GAB; average about 5000 mg/L permeability connections across Basin Patchawarra.
Permian- Murteree Shale Aquitard Generally Basin-wide Uncertain, likely high As above Very Low
Dubsky & McPhail (2001) corrected Carbon- potentiometric surface maps indicates iferous) Prior to Strike program, believed to Patchawarra Formation pressures in the order be in range 3000-18,000 mg/L, of 100 mAHD in the area about 30 km north of Highly variable. average about 9000 mg/L. Weena Trough (i.e. broadly consistent with Patchawarra Patchawarra Strike program found moderate GAB pressures). coals exhibit low Formation Reservoir Generally Basin-wide salinity in Weena Trough depocentre Pressures are influenced by regional permeability (multiple sands) (6000-7000 mg/L; samples affected aquitard/seal units of Roseneath and (typically 1-15 by stimulation fluid), where Murteree. Where aquitards present, expect mD, up to 25 Roseneath & Murteree Shales some pressure differences from GAB; where mD max.) provide an aquitard/seal. aquitards absent (e.g. certain parts of Weena Trough), expect pressures and salinity similar to GAB. Generally Basin wide Limited dataset for Tirrawarra 5000 to Tirrawarra Formation Potential reservoir except for south east and 17,000 mg/L, average about 10,000 As above Highly variable around local highs mg/L Highly variable, Pre-Permian Potential for high pressures in centre of Basin. Warburton Reservoir Basin wide Unknown may include Basement May be same or higher or less than GAB. natural fractures Note: Selected salinity values in table adjusted from Santos (2003), to be more consistent with Dubsky and McPhail (2001), including to indicate “typical or average” salinity, as well as to be consistent with data obtained during PEL 96 investigations.
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 26 hydrogeologic 5.2 Lake Eyre Basin In central Australia the shallow sediments overlying the GAB comprise the Lake Eyre Basin of Tertiary age. These sediments consist mainly of sands but also contain beds of lignite and clay. The Lake Eyre Basin sediments are recharged via rainfall and surface water infiltration from the ephemeral creeks. Shepherd (1978) reports that salinities vary from 1000 mg/L to greater than 100,000 mg/L and transmissivities are inferred to be less than 100 m2/day. In the project area, the salinities typically range from 10,000 to 20,000 mg/L. The depth to water table is typically several metres to several tens of metres (in the project area, typically 5-10 m). The sand units can host useful local aquifers that are often exploited for stock water. Localised aquifers can also be found in Quaternary alluvial sands and gravel. Information on the groundwater discharge mechanism from the Tertiary aquifer is limited in literature, although groundwater has potential to be discharged along waterways where the sediments have been eroded and the water table is shallow. However, in the project area, the depth to water is typically in excess of 5 m, and the Strzelecki Creek is ephemeral and dependent solely on local rainfall-runoff or on major flood flows from the Cooper Creek. The combination of topographical elevations and regional groundwater system discharge areas shown in Figure 19 (after CSIRO, 2012c; figure 19 is presented in Section 5.5) confirms that Lakes Blanche, Gregory and Callabonna are the only areas in the region with aquifer pressure levels above ground level, indicating potential for groundwater discharge. Even then, the only known natural GAB discharge within 50 km of the site is the spring at the northern end of Lake Blanche. Water quality data (9000 mg/L TDS) indicates that this spring may be influenced by discharge from the Tertiary aquifer (i.e. above the Bulldog Shale), which typically has salinity in excess of 10,000 mg/L, rather than discharge from the main confined GAB aquifers (1000-1800 mg/L in study area). It could also be influenced by discharge from Cooper Basin formations (6000-7000 mg/L, or 2000-3000 mg/L where influenced by downward leakage from GAB). This is considered further in Section 5.5, and further investigations and monitoring will be designed to obtain data to refine the assessment. 5.3 Great Artesian Basin (GAB) The GAB is a complex hydrogeological system comprised of (geological) Eromanga Basin sediments of variable character that form aquifers and aquitards of regional significance (see Table 4), variably confined with groundwater generally under artesian conditions (CSIRO, 2012c). A regional conceptual model of the (hydrogeological) GAB is shown in Figure 10, illustrating the relationship between the regionally extensive (geological) Eromanga Basin and the underlying and much less extensive (geological) Cooper Basin. The east-west section line (indicated in the small inset) is roughly aligned with the SA-NT border. 5.3.1 Central Eromanga Basin PEL 96 lies within the Central Eromanga Basin of the GAB (Figure 9), and on the southern margin of the Cooper Basin. The Eromanga Basin is dominated by a sequence of sandstones and siltstones of the Jurassic to Cretaceous period (DERM, 2005) which overly the Cooper Basin sands and shales of the Carboniferous to Triassic period (Draper, 2002). The Central Eromanga Basin of the GAB occupies an area of around 690,000 km2 predominantly across Queensland with small portions extending into South Australia and New South Wales. The southern boundary of the region is the Frome Embayment, which is located about 200 km south-east of the PEL 96 project area, and is characterised by a series of ranges surrounding the low relief area of Lake Frome (Davey, 2010; Davey and Hill, 2006).
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The Flinders Ranges, situated to the west of Lake Frome and south-west of PEL 96, form the highest features in this landscape, ranging from 500 to 600 mAHD (Davey, 2010). Figure 10 - Three dimensional illustration of a slice through the GAB (after CSIRO 2012c).
In various locations across the Cooper Basin, including the project area, erosion of the Cooper Basin sediments and subsequent deposition of the overlying Eromanga Basin sediments has resulted in contact or mixing between the two formations. As a result, over geologic time, hydrocarbons have migrated from the Cooper Basin into the Eromanga Basin in certain areas. Indications of trace oil and gas are typically seen in the Jurassic (GAB) aquifers during drilling into the Cooper Basin due to this migration, and in certain areas the Eromanga Basin sediments (i.e. the GAB aquifers) are oil exploration and production targets. 5.3.2 Upper and Main Confined GAB Aquifer Across the Eromanga Basin, the major GAB confined aquifer and aquitard systems are identified (CSIRO, 2012b) as the following, from shallow to deep (see also Figure 11): the “Upper Confined Aquifer (Cretaceous)” sediments of the Winton and Mackunda Formations (generally confined by the clays and shales of the Winton Formation itself and the overlying Tertiary sediments of the Lake Eyre Basin) the intervening “Main Aquitard (Cretaceous)” units of the Bulldog Shale and Oodnadatta Formation the “Main Confined Aquifer (Lower Cretaceous-Jurassic)” sediments of the Cadna- owie Formation and the Hutton (or Algebuckina) Sandstone (generally underlain by the Nappamerri Group aquitard, although this is absent at Klebb and Le Chiffre).
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Figure 11 - Stratigraphy at Klebb and Le Chiffre
The upper confined aquifer system is not artesian and is not as widely utilised as the deeper and better quality artesian aquifers of the main confined GAB aquifer system. Between the upper and main confined aquifer systems, an intermediate aquifer also exists in the Coorikiana Sandstone. The discrete Coorikiana aquifer has high salinity and low permeability in north-eastern S.A., and is generally not exploited due to its poor water quality and low yield. The confining beds separating the sandstone units of the main confined GAB aquifer pinch out over the Birdsville Track Ridge (west of PEL 96 and on the western margin of the Central Eromanga Basin). The individual sandstones (Hutton etc) merge into the Algebuckina Sandstone westwards. While the main confined GAB aquifer system is referred to as the Cadna-owie – Algebuckina aquifer system in South Australia, that technically relates to these more western areas, and the term main confined GAB aquifer will be used in this report. To the east of the Birdsville Track Ridge, and overlying the Cooper Basin in the PEL 96 area, the main confined GAB aquifer includes sediments of the Cadna-owie Formation, and the
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Murta Formation, McKinlay Member and the Namur Sandstone (a combined sequence equivalent to the Hooray Sandstone in QLD), plus the Birkhead and Hutton Sandstones (the Adori Sandstone aquifer and Westbourne Formation aquitard are both absent). 5.3.3 Hydrogeological Properties of GAB Formations An analysis of porosity and permeability data contained within the Petroleum Exploration and Production System - South Australia and Queensland Petroleum Exploration databases has been undertaken by CSIRO (2012a) for the Central Eromanga region (Table 5). Table 5 - Mean porosity and permeability values of GAB Formations in Central Eromanga Basin (CSIRO, 2012a)
Formation Number of Mean Number of Mean horizontal Hydrogeological porosity Porosity permeability permeability classification measurements (%) measurements (mD) Cadna-owie Formation 405 15 331 96 leaky aquitard Hooray Sandstone 4438 16 4222 131 aquifer Westbourne Formation 951 14 896 105 leaky aquitard Adori Sandstone 64 22 71 813 aquifer Birkhead Formation 1578 14 1348 130 partial aquifer Hutton Sandstone 2928 17 2687 452 aquifer Note: mD = milliDarcy. Darcy is the fundamental unit for intrinsic permeability, and 1 Darcy is approximately equal to 9.869233×10−13 m2 (sic, IESC 2014). For typical GAB aquifers, 100 mD translates to an equivalent aquifer hydraulic conductivity of about 0.1 m/d (IESC, 2014), which is better characterised as an aquitard rather than a productive aquifer (CSIRO, 2012b). The CSIRO study (2012a,b; summarised in Table 5) concluded that the geological formations that contain GAB aquifers have average permeability values between 100 and 1000 mD (roughly 0.1 to 1 m/d in aquifer terms), with a few measurements below 10 mD. These are somewhat low values for an aquifer, equivalent to approximately 0.1 to 1 m per year of advective horizontal groundwater movement (CSIRO 2012b). Spatially, the permeability decreases along a south-westerly gradient (i.e. towards the project area). For comparison purposes, the permeabilities of the target coal units of the Patchawarra Formation in the underlying Cooper Basin have been estimated by Strike at up to 25 mD (roughly 0.03 m/d). In the central portion of the Eromanga Basin, the Cadna-owie Formation (upper part of the main confined GAB aquifer) has an average permeability of 96 mD, which is a low value for an aquifer (roughly 0.1 m/d), and in many areas the permeability characteristics would be better described as an aquitard (CSIRO, 2012b). The upper Wyandra Sandstone member of the Cadna-owie is identified in regional terms as a nominal aquifer (CSIRO 2012b). However, in some areas of the Eromanga Basin, explorers and producers have encountered serious difficulty trying to recover water or oil from the Cadna-owie. The geological formations known to contain GAB aquitards (e.g. Westbourne Formation) have average permeability values between 10 and 100 mD (i.e. consistent with the means of the aquifer units), and is equivalent to about 1 cm per year of horizontal groundwater movement (CSIRO, 2012b). Aquifer storage coefficient information is limited. Storage coefficients calculated from petroleum well log data and independently from bore testing range from 1x10-4 to 1x10-5 (GABCC, 2010), which is at the low end of the expected range for a productive aquifer. 5.3.4 GAB Groundwater Levels, Flow, Recharge and Discharge Groundwater levels in the main confined GAB aquifer are shown in Figure 12 for a series of timeframes since 1900 (CSIRO, 2012c). The groundwater flow in the GAB is generally to the south-west within the central Eromanga Basin. Figure 13 shows groundwater flow directions within the entire GAB. Recharge primarily occurs through infiltrating surface water and rainfall in formation outcrops in northern Queensland and in the high rainfall areas on
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 30 hydrogeologic western slopes of Great Dividing Range (see also Figure 5). There is also some leakage upwards to the GAB from deeper units (Figure 13). The aquifers of the GAB are also recharged in the south-eastern portion of the Northern Territory and the northern section of the Flinders Ranges in South Australia (CSIRO, 2012c). Figure 12 – Groundwater level time series - main confined GAB aquifer (CSIRO 2012c)
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 31 hydrogeologic
Figure 13 – 3D view of GAB showing principal flow paths relatively stagnant in depocentre (after CSIRO 2012b, Figure 8.9)
With reference to Figure 13, the 2012 CSIRO study identified that significant regional groundwater flow in the GAB is relatively limited to areas adjoining the recharge zones where the aquifer has shallow burial (i.e. remote from the Central Eromanga Basin and the project area). The deeper regions of the GAB have very low flow and are characterised as “relatively stagnant” (flow velocities of 0.03 to 0.3 m per year) in contrast to the moderate velocities of 1.2 to 2.5 m per year for younger waters. This is illustrated in Figure 13 (after CSIRO 2012b, Figure 8.9), which shows very little through-flow in the Eromanga depocentre (shown as the dark blue area) and also on southern margins near the project area (indicated by the red box). The yellow to orange shading on the flow arrows indicate increasing salinity along the southern flow path in the project area. The vertical connectivity of the GAB with the overlying shallow Cainozoic sediments is poorly understood but assessments of the pressure differences have indicated a potential for interconnection (CSIRO, 2012b). Across most of the GAB, particularly in the Central Eromanga Basin, the groundwater levels in the main confined GAB aquifer are higher than the water table in the overlying shallow units. This indicates that the majority of the GAB has the potential to be subject to artesian conditions and that upward vertical leakage could occur through leaky aquitards, including in the project area. However, the drilling at Klebb-1 and Le Chiffre-1 has identified a Bulldog Shale thickness of about 200 metres, which would substantially reduce the potential for cross-formational flow. Overall, the latest understanding from the recent CSIRO (2012a) study suggests that there is a minor component of groundwater that is very slowly traversing the entire GAB to discharge on the south-western margin in the Cooper region, and also that there is an
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 32 hydrogeologic unquantified component of upward leakage from the underlying Cooper Basin contributing to through-flow in the Eromanga system (see also Figure 14). A schematic (water balance type) representation of the GAB recharge and discharge mechanisms is presented in Figure 14. Groundwater from the GAB discharges naturally in the form of concentrated outflow from springs, along with vertical leakage from the lower GAB to upper GAB and upwards to the regional water table, and subsurface outflow to adjoining basins (Habermehl, 1980). Other discharge occurs by means of free or controlled artesian flow and pumped abstraction from the water bores drilled within the GAB. Flowing artesian springs within the Basin and discharge areas are associated with structural features such as faults, folds, monoclines, and intersections of structural lineaments. Upward groundwater flow along faults is understood to be the source of many springs. For comparison purposes in relation to the water balance volumes of Figure 14 (and as explained in detail in Section 6), the projected groundwater production volume from the 6-month Strike appraisal test amounts to 0.44 GL (based on very conservative assumptions). Figure 14 – Groundwater Balance of Eromanga Basin (after CSIRO, 2012b)
Note: Cooper Basin area is shown by left-most upwards blue arrow. 5.3.5 GAB Groundwater Use and Water Balance The main confined GAB aquifer in the Central Eromanga region is the principal source of water for industry in the north of the South Australia (SAALNRM Board, 2009). Artesian water is primarily used for stock watering and/or road maintenance purposes, often accessed through converted exploration wells (due to drilling depth/cost issues). The petroleum industry also extracts water from the Eromanga (GAB) and Cooper Basins as a result of petroleum production. The majority of oil producing reservoirs in the Cooper and Eromanga Basins are classified as ‘water drive’ reservoirs. The hydraulic head (pressure) from the water in the sandstone unit provides a source of pressure that flushes the oil through the pore space of the rock towards the wellbore. As a result water is produced with the oil. This water is separated from the oil stream at production facilities, with disposal typically to surface evaporation ponds, consistent with Statements of Environmental Objectives. The Far North Water Allocation Plan (SAALNRM Board, 2009) has established an “indicative allocation volume” for co-produced water at 60 ML/d (21.9 GL/a) and the Minister for
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 33 hydrogeologic
Mineral Resources and Energy holds a water licence for this allocation. The historical peak in 1994 was estimated at 34 ML/day, of which 3 ML/d was estimated from the Cooper Basin. More typically over subsequent years, the co-produced volume has been about 25-33 ML/day (DMITRE, 2014), mostly from the Eromanga Basin (and mostly concentrated near Moomba), with perhaps 1 ML/day from the Cooper Basin. In water balance terms, sustainable diversion limits have been established by the Water Allocation Plan (WAP). For co-produced water the limit is 60 ML/d (as discussed above), which is about twice the current volume that is produced and about twice the historical peak. Further detail is provided in Section 6 when discussing the impact assessment in the context of the Far North WAP. 5.3.6 GAB Groundwater Quality Depending on location, groundwater salinity in the GAB aquifers can range from fresh to saline (Figure 15). Groundwater in the most widely exploited confined aquifers in the Lower Cretaceous-Jurassic sequence generally contains about 500 to 1500 mg/L total dissolved solids (CSIRO, 2012c). Higher concentrations have been noted within the central and southern part of Central Eromanga Basin (Figure 15), in the region of the project area (shown as a small red box). The yellow to orange shading on the flow arrow in Figure 13 (presented above) indicates increasing salinity along the southern regional flow path in the project area SA government records of GAB bores within 100 km of the site (mostly south and west of Klebb) are presented in Appendix A. Figure 15 – Salinity in the main confined GAB aquifer (a) and the upper confined GAB aquifer (b) and their equivalents (after CSIRO 2012c)
Artesian groundwater has pH values that are usually between 7.5 and 8.5 (CSIRO, 2012c). Near the recharge areas, concentrations of Ca, Mg and SO4 are proportionally higher, but these decrease towards the centre of the basin. Variations of the major ion concentrations and ratios occur along the flow lines in most parts of the GAB, including concentrations of Na and HCO3, resulting in elevated sodium adsorption ratios (SAR) and alkalinities, respectively (CSIRO, 2012c), which can limit the suitability of water for irrigation purposes. Analysis of historical groundwater sample data (Appendix A) on major ion composition from different aquifers in the PEL 96 region reveals characteristic water types that provide clues
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 34 hydrogeologic on the source water for GAB springs in the area (a Piper diagram is presented in Appendix A). The hydrochemical analysis undertaken for this assessment is comprehensive and included unpublished data on the Lake Blanche and other GAB springs provided by BHP Billiton but without authority to publish the data herein. Please note that this data is not plotted in the Piper diagram presented in Appendix A, although the interpretations presented herein are based on this comprehensive data and are valid. A draft monitoring plan has been developed to obtain detailed information from a range of GAB bores and springs to confirm these interpretations. Consultation is in progress with DEWNR on the draft monitoring plan, leading to development of a monitoring and management plan, and the data obtained will be published in due course. In general, groundwater from the Tertiary aquifers is Na-Cl dominated, consistent with the elevated salinities of these formations. In contrast, groundwater from the main confined GAB aquifer in the region surrounding PEL96 is Na-HCO3-Cl dominated. Importantly, the composition of Lake Blanche spring water is Na-Cl dominated, providing further evidence that this spring may be substantially influenced by components of discharge from the Tertiary aquifer (and/or possibly by leakage from the Cooper Basin) and may not be sustained wholly by discharge from the main confined GAB aquifer. The chemical and isotopic composition, and therefore likely source aquifers, of the other spring complexes within the Lake Frome supergroup will be assessed during the appraisal program. 5.3.7 GAB Groundwater Dependent Ecosystems (GDEs) Certain ecosystems may depend on groundwater from the GAB aquifers (e.g. GAB springs) including wetlands and terrestrial vegetation that may also rely on the availability of shallow groundwater (CSIRO 2012c). Wetland GAB springs are often referred to as either recharge or discharge springs (Fensham and Fairfax, 2003; Fensham et al., 2012). Recharge springs have been defined by their occurrence in the outcropping sandstone formations on the eastern margin of the GAB in Queensland (i.e. remote from the Central Eromanga Basin and the project area). In these areas the groundwater level of the source GAB aquifers is lower than the local ground topography except at the immediate location of the spring (non-artesian). Discharge flow from these “recharge springs” subsequently infiltrates and potentially adds to the recharge zone processes on the margins of the GAB. Discharge springs are sourced from aquifers of the GAB with a groundwater level that is historically higher than the ground topography at the location of the spring (artesian), and where there is a structural feature that allows for hydraulic connection to the surface. In general, a range of hydraulic connections have been interpreted: 1) geological structures, where water flows upward through a fault 2) abutment, where aquifers abut against an impermeable outcrop, or 3) where groundwater breaks through to the surface through a thin confining layer (CSIRO, 2012c). Figure 16 shows the distribution of groundwater fed spring complexes in the Central Eromanga Basin, some of which are EPBC Act listed. Of the springs in the Lake Frome Supergroup, most are very remote from the drilling sites, with the closest being a mapped spring (and related set of 10 potential spring vents) on the north-western margin of the bed of Lake Blanche, mapped at about 50 km from the site (these are shown in some detail in Figure 18, presented later).
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 35 hydrogeologic
Figure 16 – Spring complexes of the Central Eromanga region (after CSIRO 2012c).
The red box in Figure 16 shows the approximate location of the site, and the dashed line on the background map is an indicative Lake Frome spring supergroup boundary, which must not be confused with the Southwest Springs Zone that is referred to in the Far North WAP, and is shown in Figure 18 (presented later). The boundary of PEL 96 extends to the western shore of Lake Blanche, and thus lies just inside the boundary of the Southwest Springs Zone, and within the 5 km exclusion zone around the mapped Lake Blanche spring group. 5.4 Cooper Basin Hydrogeology The Cooper Basin is comprised of sedimentary rock layers of variable character that typically form reservoirs for gas (including coal gas) and may also form aquifers and aquitards. The Cooper Basin is not traditionally associated with groundwater resources, largely because of the importance, quality and accessibility of the overlying groundwater system in the GAB. Other factors reducing the relative value of potential Cooper Basin aquifer resources include the drilling depth and cost involved and the lower yield and brackish to saline water quality. The Cooper Basin and the GAB are generally separated by the Nappamerri Group (an aquitard and regional seal), which has a substantial thickness in most areas. Recent drilling at Klebb and Le Chiffre has confirmed the absence of the Nappamerri Group aquitard at Klebb-1 and
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 36 hydrogeologic
Le Chiffre-1, although the Roseneath Shale and Murteree Shale aquitard units are present, with identified aquitard thicknesses of 16-33 m each (see Figure 11 and also Table 3). There is limited hydrogeological information available on the properties of the Cooper Basin aquifer and aquitard units (Table 5). Youngs (1971) noted that too few data were available at the time to produce reliable potentiometric surface maps, but noted that the Upper Member had a very undulating potentiometric surface; a feature thought to be caused by considerable infiltration of foreign groundwater. Dubsky and McPhail (2001) prepared a corrected potentiometric surface map, but that did not extend to the Weena Trough. However, it indicated Patchawarra Formation regional flow gradients towards the south and pressures in the order of 100 mAHD in the area about 30 km north of Weena Trough (i.e. broadly consistent with GAB pressures). Gravestock et al (1998) indicate Patchawarra Formation permeability typically in the order of 1 to 10 mD (roughly 0.001 to 0.01 m/day) and rarely exceeding 100 mD, representing aquitard properties. Very limited groundwater quality data is available for Cooper Basin formations in this region. Analyses for the Klebb-1 and Le Chiffre-1 wells from flowback after stimulation (which are affected by the stimulation fluids and are not representative of the Cooper Basin) indicate a salinity of 6,000-7,000 mg/L and pH of 7.6 to 7.8. Apparent resistivity log data for Waitpinga-1 (about 20 km north of Klebb-1, but in PEL94 – see Figure 2) provides an indicative salinity of about 3300 mg/L. Lower salinities of 2,338 mg/L and 2,050 mg/L were recorded during drilling of the Tinga Tingana-1 well (7 km north-east of Le Chiffre-1) and Cherri-1 well 17 km (south-east of Le Chiffre-1) in 1968-70 (see Figure 2 for localities). In this structurally high are of the Weena Trough, the Patchawarra Formation is directly overlain by the Hutton Sandstone at Tinga Tingana, and the Hutton overlies the Epsilon at Cherri-1. The lower salinities have been interpreted as due to downward leakage from the typically lower salinity GAB aquifers (Dubsky and McPhail, 2001). Reliable salinity data for the Patchawarra coals at Klebb and Le Chiffre will be obtained after the wells have been flowing for several weeks. At the project sites, there is similar potential for connection between the upper Cooper Basin unit siltstones and sandstones of the Toolachee and/or Epsilon (overlying the Roseneath aquitard) and the basal Eromanga unit of the Hutton Sandstone. There is also potential for interconnection in the extreme south-western and western parts of the Weena Trough, as discussed in sections 4.3 and 5.5. It is planned to obtain data on aquifer pressures and water quality in the Hutton and Toolachee during and following the appraisal program, to improve the hydrogeological understanding. 5.5 Local Hydrogeology 5.5.1 Weena Trough The site lies within the Weena Trough (Figure 8), which is itself located on the southern margin of the Cooper Basin. Figure 17 presents a conceptual hydrogeological model visualisation using seismic interpretations from the SARIG knowledge base, which does not extend across the entire PEL 96 area, and shows major gaps in some units (notably Eromanga), which defies clarity of presentation in 3D block models or cross-sections. Consultation with DEWNR (Dec 2014) has identified new data from their re-mapping of the Eromanga, which will be used to improve the conceptual 3D block model, and if practicable to develop cross-sections across the Weena Trough, as the project progresses. Within PEL 96, the shallow Cainozoic Sediments are about 250 m thick and form the topmost Tertiary aquifer, while the underlying GAB has a thickness of around 1100-1300 m (Table 3). The deeper Cooper Basin formations in the Weena Trough are generally thicker towards the centre of the Trough and tend to pinch out towards the structural highs (Figure 8). In the Weena Trough depocentre, the Cooper Basin sediments are about 600 m thick, while along the structural highs the thickness reduces to less than 200 m.
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GEOLOGY ± Tertiary Eromanga (Data limited to extent shown) Cadna-Owie
6939-13 Permian 6939-12 6939-3 Basement Warburton 50m 6939-2 6939-15 6939-14 MONTECOLLINA BORE (GAB) 6939-11 6839-2 6839-3 6939-9 (5500-7100mg/L TDS) -250m LE CHIFFRE-1 BOBS BORE (2470mg/L TDS) 6939-10 (TERTIARY WATER BORE (8800mg/L TDS) 8500mg/L TDS) -550m 6939-24 6839-1
6939-19 -850m 6839-10 KLEBB-1 mAHD -1150m (TERTIARY WATER BORE 12,000mg/L TDS) LAKE BLANCHE
-1450m
6839-5 (LAKE BLANCHE SPRING) -1750m (9170mg/L TDS)
INDICATIVE KLEBB-1 -2050m
-2350m
-2650m ± LEGEND !( Strike Energy Well HORIZONTAL SCALE ! COOBER PEDY 5 0 5 10 !( GAB Bore ROXBY DOWNS FIGURE 17 ! Kilometres !( Strike Energy Drilling Water Supply Bore BROKEN HILL CEDUNA ! ! GDA 1994 MGA Zone 54 !( PEL96 Conceptual Geology ! Tertiary/Quaternary Bore ! WHYALLA
RENMARK DATA SOURCES Watercourse ! ! PORT LINCOLN Geoscience Australia ! ADELAIDE MILDURA ! SARIG SWAN HILL ! Strike Energy PEL 96
HORSHAM Disclaimer: While all reasonable care has been taken to ensure the information contained on ! BENDIGO! ! this map is up to date and accurate, no guarantee is given that the information portrayed is SEYMOUR free from error or omission. Please verify the accuracy of all information prior to use. ! ! hydrogeologic
The hydraulic connection between the GAB aquifers and overlying shallow groundwater systems is poorly known (CSIRO, 2012a), but is considered to be limited in the depocentre area, based on the following (further detail is provided in sub-sections below): the 200 metre thickness of Bulldog Shale encountered at the sites there is only one mapped GAB spring identified within 50 km of the site, located on the north-western corner of Lake Blanche, exhibiting low pressure and with a salinity of 9170 mg/L (suggesting influences of discharge from a Tertiary aquifer source) of the 18 GAB wells identified within 100 km of the site, there is only one bore within 40 km (Montecollina Bore) which has salinity values in the range 5500-7100 mg/L, also indicating some influence from the more saline shallow Tertiary formations (and/or perhaps the Bulldog Shale). This investigation has not identified any specific data on vertical gradients in the Montecollina bore area, other than the information from reports cited herein (notably CSIRO, 2012; Dubsky and McPhail, 2001). Section 5.5.3 presents further information and interpretations regarding vertical aquifer connectivity and direct contact between the Hutton and Patchawarra formations in certain nearby areas (e.g. Tinga Tingana-1 and Cherri-1). Recent drilling at Klebb and Le Chiffre at the Weena Trough depocentre confirmed the absence of the Nappamerri Group aquitard/seal in this area (see also Table 3 and Figure 11). At these sites, the Permian Toolachee Formation is in direct unconformable contact with the Jurassic Hutton Formation (the deepest GAB formation). Underlying the Toolachee Formation, the Roseneath Shale forms a 16-17 m thick aquitard/seal to the Epsilon Formation. Similarly, the Murteree Shale forms a 26-33 m thick aquitard/seal between the Epsilon Formation and the Patchawarra Formation. These aquitards/seals should provide an effective barrier to potential leakage to/from overlying aquifers. The drilling at Klebb and Le Chiffre has also confirmed 90-120 m thicknesses of low permeability siltstones and sandstones in both the Toolachee Formation and the Epsilon Formation, and 300-330 m thicknesses of low permeability siltstones and sandstones in the Patchawarra Formation (with intervening coal seams). The PEL 96 target Patchawarra coal seams (Vm3 and Vu) were thicker than expected (up to 66-89 m) with an additional coal unit (16 m thick) below the Vu coal. Potential reservoir sands were water saturated with low permeability siltstones present between sandstones and the target coals. 5.5.2 Local Hydrogeological Properties There are limited site specific quantitative hydrogeological parameters (hydraulic conductivity, porosity and storage parameters) available for the Weena Trough. The drilling and testing to date at Klebb and Le Chiffre indicate low coal unit permeability values, ranging from 2 to 25 mD (roughly 0.002 to 0.03 m/day), with a typical value of about 15 mD (roughly 0.01 m/d), confirming low aquifer potential and low potential for inter- connection between the Patchawarra Formation and other units vertically or laterally. 5.5.3 Potential Vertical Connectivity The geological units of the Weena Trough pinch out on all margins of the Weena Trough (east, south and west - Figure 8). In the absence of the Nappamerri Group aquitard/seal at the sites, there is potential for connectivity between the sub-cropping Cooper Basin formations and the GAB. For example (and as outlined previously, e.g. Section 4.3), Tinga Tingana-1 is located about 7 km north-east of Le Chiffre-1 (within PEL 96), where the Hutton is in direct contact with the Patchawarra, and it shows a salinity value of 2050 mg/L. Cherri-1 is located about 17 km
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 39 hydrogeologic south-east of Le Chiffre-1, with similar geology and a salinity value of 2338 mg/L. This is notable as it is demonstrates that within certain areas of PEL 96 (e.g. where aquitards are absent), there is substantial downward leakage from the Jurassic GAB to the Permian Cooper units (Dubsky and McPhail, 2001). This is interpreted as being mainly due to the absence of the Nappamerri Formation regional aquitard/seal, as well as the Roseneath and Murteree Shale aquitard units. The presence of the Roseneath and the Murteree Shale at the Klebb and Le Chiffre sites, however, would substantially constrain the potential for downward leakage from the GAB during the appraisal testing program. While there is evidence that downwards leakage from the GAB has already occurred within PEL 96 (north-east and south-east of the site, where aquitards are absent), in other areas nearby, the east-west trending fault-bounded graben structures of the Weena Trough (Figure 4, Figure 8) are at the Permian level and are syn-depositional. This indicates low potential connection for Permian water to interact with the Jurassic GAB aquifers via fault structures in the Weena Trough project area. 5.5.4 Local Groundwater Levels, Salinity, Flow, Recharge and Discharge Appendix A shows the results of a search of the South Australian government’s WaterConnect database for bores within 100 km of the Klebb and Le Chiffre sites. The results are also plotted spatially in Figure 18. The search identified 185 bores in the shallow Tertiary sediments (typically less than 150 m depth) and located within a 100 km radius from the site. Of these bores, 104 are listed as being ‘Operational’. Groundwater levels recorded for these bores range from 0.3 to 90 m below ground level (Appendix A). The data available indicates that Bobs Bore was pumped at 3 L/s, with a salinity of 8800 mg/L TDS, while Strez Bore yielded 1.8 L/s at 16,000 mg/L TDS. Strike Energy has also drilled water supply bores at the Klebb and Le Chiffre sites to depths of up to 120 metres to support drilling activities. These bores yielded TDS values of 12,000 and 8500 mg/L (for Klebb and Le Chiffre sites, respectively) and pH values of 7.5. The Tertiary aquifer is recharged via locally infiltrating surface water and rainfall (CSIRO 2012a; 2012c). The search identified 18 GAB wells within a 100 km radius, drilled to depths of 280-1100 m. Groundwater level data indicates that, of these wells, over 60% are flowing under artesian conditions (Appendix A). The majority of these wells remain open (Figure 18) and operate either as ‘Controlled Flowing wells’, ‘Controlled Shut-in wells’ or ‘Uncontrolled Flowing wells’ (WaterConnect Groundwater Data, 2013). Groundwater levels in the main confined GAB aquifer system range from 17 m below ground level (i.e. sub-artesian, possibly a well completed in the Coorikiana aquifer) to 80 m above ground level (artesian). The upper confined GAB system (including Coorikiana) is sub- artesian. The closest GAB well to the site is 6839-3 (Montecollina Bore and its related bore-fed wetland), which is located adjacent to the Strzelecki Track about 40 km south of Klebb and Le Chiffre (and about 40 km east of the spring at the northern end of Lake Blanche – see Figure 18). It is drilled into the Cadna-owie Formation, with data indicating a temperature of about 45C, artesian pressure of up to 22 m, and salinity in the range 5500 to 7100 mg/L. The remainder of the identified GAB bores in the region are located more than 70 km away from the site, mostly to the south-west of Lake Blanche. The groundwater in the GAB in this region flows towards the south-west, with indications of increasing salinity in that direction (Figure 13). The GAB and Cooper Basin systems have no identified recharge within the PEL 96 area (Figure 5). South and west of PEL 96, the GAB aquifers can also receive some recharge inputs from the northern section of the Flinders Ranges (CSIRO, 2012c).
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 40 285000 335000 385000 6941-227 435000 485000 6941-213 COOBER PEDY ! 6841-69 6941-226 6941-225 MOOMBA 6841-14 ! 6941-85 6841-84 6841-23 6941-86 ROXBY DOWNS 6841-13 ! 6841-66 6841-22 6941-224 6941-270
6841-68 6941-537 BROKEN HILL CEDUNA ! 6941-169 ! PORT AUGUSTA 6841-67 ! *#*# 6941-171 WHYALLA *# *# ! 6841-82 #* *# * *#*# *# *# 6941-176 6941-638 7041-42 RENMARK 6841-71 ! ! 6941-74 PORT LINCOLN *# 7041-250 ! ADELAIDE MILDURA 6841-79 *# *# *# ! # *# 6941-236 ! 6841-80 *# *# * *# *# 7041-251 6841-9 *# *# *# 6941-497 6941-542 7041-249 *# 6841-62 QUEENSLAND 6841-4 *# *# *#*# 6941-24 *# 6841-61 6941-496 6858000 6841-8 *#*## 7041-46 6858000 *# 6841-31 *# 6941-181 *# 6841-7 7041-38 6841-58 6841-63 *# 6940-56 6841-6 6941-40*#
6841-59 6841-64 *# 6940-31 *# 7040-16
6940-140 *#*# LEGEND * 6841-78 *# *# *# 7040-17 #
*# *# 6940-12*# *#
K 6841-74 7040-45 Strike Energy Drilling Water Supply Bores * # MERTY MERTY E # Klaus Bore E 6941-235 * 7040-23 ! CR 6841-77 *# *# R 6840-14 *# *# *# Strike Energy Proposed Wells E 6841-73 6940-32 *# OP *# O 6840-12 *# *# C 6940-26 6940-2 *# *# Potentially Operational GAB Bores
6840-11 *# 7040-15 7040-18 *#
6940-162 *# 6940-74*# Within 100km Radius of Site * 7040-7 *# # 6940-54 7040-14 6840-9 6940-33 *# 6940-66 *# 7040-27 # Potentially Operational Tertiary/Quaternary 6840-17 6940-45 *# 7040-6 * Bores Within 100km Radius of Site
1m Pressure Target *# 6940-27 6940-65
6840-16 Popes Bore 7040-25 A@ * # 6940-87 Spring 6840-15 6940-75 7040-4
Waitpinga BP10 Maslins WB 7039-17
6840-18 *# *# 6940-64 *# ! 6808000 7039-9 6808000 Locality
*
# 6940-306940-29 # 7040-5 * *
LAKE GREGORY 6840-25 6940-70 # 6940-28 *# *# * *# # *#*# 6940-105 7040-32 7040-8 7040-31 1m Pressure Target 6939-11 6940-106 Seacliff *# 7039-10 6940-44 Strez Crossing bore Watercourse 6939-9 6939-10 *# 7039-20*# # *# 6939-12 *#*# *# *# *# *#**# 6739-11 *# *# *# *# 6939-13 Track KLEBB 7040-26 7039-5 *# *# 6939-24 7039-4 7040-29 6739-16 5km Spring 6839-1 LE CHIFFRE 6939-19 7039-11 State Boundary *# 7039-7 Exclusion Zone 6839-10 6940-73
6739-10 *# *# 5km Spring Exclusion Zone
6939-3 *# * *# *# 6939-15 # 7039-18 *# 6939-14 # 6939-2 7039-19 # Inland Water PEL 96 *# *# * 6739-7 *# 6839-2 Bobs Bore 7039-8 LAKE BLANCHE A@ 6839-5 Petroleum Exploration Licence A@*# *# 7039-25 SPRINGS *# *#7039-16
6739-2 LAKE BLANCHE *# PEL 96 NEW SOUTH WALES SOUTH NEW *# AUSTRALIA SOUTH 6939-23 7039-6 6758000 6758000 6739-3 *# 6939-22 *# *# REEDY 6839-3 7039-1 6839-8 *# SPRINGS 6838-10 *# *# 7039-15 6739-17 *# 6838-44 # 6739-6 *#6839-6 6838-5 * ± *#*# *# 6838-11 6838-6 15 0 15 30 Kilometres A@ 6738-73 6838-4 6739-5 A@ 6838-43 APPROX SCALE 1:1,250,000 @ A4 6738-189 A@A@ *# *# 6838-42 7038-1 # GDA 1994 MGA Zone 54 6739-12 A@*#* 6838-54 6838-53 7038-4 *# *# *#*# *# 6838-15 7038-2 *# 6738-75 6738-24 *# *# *# 6838-8 6838-3 6838-7 6738-7 *#*# *# 6838-9 *# 6838-14 6838-33 DATA SOURCES RPS *# 6838-48 Geoscience Australia 6838-13 # SARIG 6738-70 *# *# A@A@A@A@A@A@A@A@A@A@A@ LAKE CALLABONNA 6708000 PUBLIC HOUSE/PETERMORRA A@A@ *# 6708000 6838-45 *# Disclaimer: While all reasonable care has been taken to ensure the information contained on SPRINGS *# 6838-29 this map is up to date and accurate, no guarantee is given that the information portrayed is 6838-306 6838-32 6938-5 free from error or omission. Please verify the accuracy of all information prior to use. A@ *# A@ *# 6938-2 6838-25 *# *# 6938-3 6838-51 6838-27 *#*# *# *# 6838-22 *# 6838-35 TWELVE *# *# FIGURE 18 SPRINGS 6838-23 6838-55 6838-59 6838-56 6838-28 Groundwater Bores and Springs ! 285000 335000 6838-47 385000 6838-24 435000 485000
! ! hydrogeologic
There is limited hydrogeological information available on the Cooper Basin formations. While Dubsky and McPhail (2001) prepared a corrected potentiometric surface map, it did not extend to the Weena Trough. However, it indicated Patchawarra Formation regional flow gradients towards the southern Cooper area and pressures in the order of 100 mAHD in the area about 30 km north of Weena Trough (i.e. broadly consistent with GAB pressures). Groundwater discharge occurs mainly from the GAB aquifer system in the low elevation areas surrounding the ephemeral salt lakes (Lake Blanche, Lake Callabonna and Lake Gregory), and also at Lake Frome. These lakes are remote from the drilling sites at 30 km, 60 km, 90 km at their closest points, respectively, and Lake Frome is 140 km from the site (Figure 19, after CSIRO, 2012c). GAB spring discharges are present in the north-western corner of Lake Blanche, about 50 km from the drilling sites (see also Figure 20), and also further to the south-west (on the flanks of the Flinders Ranges), and south near Lake Callabonna (south of Lake Blanche and north of Lake Frome). See also Figure 6, Figure 18 and Figure 19. Figure 19 - Digital Elevation Model showing water table groundwater discharge areas, after CSIRO 2012c. The red box indicates the approximate location of PEL 96.
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5.5.5 Local Groundwater Use Groundwater resources within the Far North Prescribed Wells Area (PWA) are managed under the Natural Resources Management Act 2004. The Far North Water Allocation Plan (WAP) has been developed for the area and provides a set of rules for South Australian users of the GAB (SAALNRM Board, 2009). The South Australian Government’s WaterConnect database indicates that groundwater use in the region of PEL 96 is restricted to a number of scattered deep petroleum wells converted for stock purposes and GAB observation and monitoring. The closest bore to the site is Montecollina, located 40 km to the south, and most are more than 70 km distant (see previous section). Montecollina Bore is used for recreation by tourists and for road maintenance on the Strzelecki Track, although the bore-fed wetland also provides support to birdlife and opportunistic vegetation. Lindon Station uses Fortville Bore (approximately 80 km to the east) as a principal water source. There is a fundamentally low risk of impacts on existing GAB bores, given the lack of their proximity to the site. Strike Energy utilises several water bores to haul water for drilling and fracture stimulation activities: including ‘Strez crossing bore’ (6940-44), ‘Maslins bore’ (6940-87), ‘Bobs bore’ (6939-15), indicated on Figure 18. These bores, along with ‘Klaus bore’ (6940-45), are also used by other operators and for road maintenance purposes. Strike has also drilled water bores at the Klebb-1 and Le Chiffre-1 sites for drilling water supply. See Section 5.5.4 for further information on these sites. As noted previously, Cooper Basin aquifers are not utilised as they are overlain by the productive aquifers of the GAB, and because deep (expensive) bores would be required, not justifying the low yielding and brackish to saline water (i.e. Cooper Basin has very limited utility as a water resource). 5.5.6 Local Groundwater Quality Strike has recently undertaken groundwater monitoring on the Tertiary bores in the area (i.e. Strez bore, Maslins bore, Bobs bore and Klaus bore, and the Klebb and Le Chiffre site water bores) in the shallow Tertiary aquifer within the licence area. Results show that Tertiary aquifer salinity is about 8500 to 21,000 mg/L TDS, with pH of between 7 and 8 (Appendix A). Salinity of groundwater from the GAB units in the southern Cooper Basin area is typically 1000 to 1800 mg/L. Some bores completed in the Bulldog Shale show up to 12,000 mg/L, and other bores with high salinity values cannot be confirmed as representative of GAB units. The Montecollina GAB bore is located about 40 km south of Klebb and Le Chiffre (and about 40 km east of the spring at the northern end of Lake Blanche – see Figure 18). It is drilled into the Cadna-owie Formation, with data indicating a temperature of about 45C, artesian pressure of up to 22 m, and salinity in the range 5500 to 7100 mg/L. The remainder of the identified GAB bores in the region are located more than 50 km away from the site, mostly to the south-west of Lake Blanche. Groundwater quality data for southern Cooper Basin formations comprises: analyses for the Klebb-1 and Le Chiffre-1 wells which may be affected by stimulation fluids (i.e. not representative of the Cooper Basin) indicate a TDS of 6000-7000 mg/L and pH of 7.6 to 7.8 apparent resistivity log data for Waitpinga-1 (about 20 km north of Klebb-1, but in PEL94 – see Figure 2) indicates salinity of about 3300 mg/L
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Tinga Tingana-1 indicates a TDS of 2050 mg/L and Cheri-1 indicates 2338 mg/L, both from the Patchawarra Formation but with directly overlying Hutton Sandstone, suggesting downward leakage from the GAB (Dubsky and McPhail, 2001). 5.5.7 Local Groundwater Dependent Ecosystems (GDEs) Terrestrial GDEs are formed where there is groundwater discharge to the surface or shallow water table under the surface. Subterranean GDEs can comprise microbial and stygofauna populations that live within saturated aquifers, usually in the shallow horizons to several tens of metres depth (Hancock and Boulton, 2007). GDEs can be sensitive to changes in groundwater levels and quality. The most notable GDEs in this region are GAB springs. The ephemeral creeks and lakes are dependent on intermittent surface flows (not groundwater). Lake Frome itself (located roughly 140 km from the site) as well as the smaller interconnected salt lakes to the north including Lake Blanche are aligned with a potential groundwater discharge zone (i.e. where aquifer piezometric levels are higher than ground level; CSIRO, 2012c; see also Figure 19). However, Lake Blanche is dependent on surface water flows and is not a groundwater- dependent water body. The GAB spring at the northern end of Lake Blanche is a GDE. Literature shows that GAB-fed discharge springs are present in the spring supergroup region of Lake Frome (Figure 16; CSIRO, 2012c). Over 700 individual springs have been noted in this region, all of which are EPBC-listed due to their environmental significance (CSIRO, 2012c; Fensham et al, 2012). However, almost all of the 700 springs are located remote from the project site. There is one spring (with 10 related minor vents) mapped at 50 km from the site on the north-western margin of Lake Blanche (Figure 18 and Figure 20). Figure 20 - Lake Blanche spring (6839-5)
The one data record on the WaterConnect web site for this spring (6839-5) is from 1969 and indicates a TDS of 9170 mg/L. There is also a recently reported mean salinity for the spring group of 15.2 mS/cm or about 8300 mg/L (Gotch, 2013). The data suggests that the Lake Blanche Spring (and possibly also Montecollina Bore, the nearest GAB bore) may be influenced by discharge from other aquifers. For example, the shallow Tertiary formations and/or perhaps the Bulldog Shale, which both usually show >10,000 mg/L (i.e. rather than the GAB (typically <2000 mg/L), may have an influence. The Cooper Basin aquifers may also have an influence (typically 3000-7000 mg/L, or sometimes lower, such as at Tinga Tingana and Cherri)). Detailed hydrochemistry and isotope data is planned to be obtained from GAB
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 44 hydrogeologic bores and springs as part of the PEL 96 appraisal testing investigations. Data available to date is presented in Appendix A, including a Piper diagram. The major potential threat to these springs is reduction in Great Artesian Basin pressures leading to the reduction or extinction of spring flow and consequent decline in the ecological character by reducing the range of wetland habitats, connectivity and ecological conditions. However, there is a low risk of this occurring due to the current project, as detailed in Section 6.
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6 IMPACT ASSESSMENT 6.1 Assessment Approach While there is a reasonable level of broad hydrogeological knowledge in the region, notably documented in the 2012 CSIRO studies of the GAB (cited herein), there is limited specific hydrogeological data available on Cooper Basin aquifer and aquitard systems in the project area. The small scale exploration, production testing and appraisal program by Strike will improve the hydrogeological understanding and information, especially regarding uncertainties and data gaps on aquifer inter-connectivity and potential GAB spring effects to the south-west towards Lake Blanche. Until more detailed data can be obtained on the structure and properties of the Cooper Basin formation in the western areas of the Weena Trough, including the nature of connections with the GAB, it was considered prudent that the hydrogeological impact assessment of the appraisal testing program conservatively assume production directly from the Hutton Sandstone. Consultation with DEWNR confirmed the suitability of this approach. This conservative approach also allows the activities to be assessed under the Far North Water Allocation Plan (WAP) developed for the area, which provides a set of rules for sustainable water use for South Australian users of the GAB (SAALNRM Board, 2009). The WAP sustainable extraction criteria include the following (see also Figure 18 for locations of exclusion zones): a water balance constraint established by the WAP (principle 2) comprising an “indicative allocation volume” for co-produced water of 60 ML/d (21.9 GL/a); in water balance terms, the PEL 96 appraisal testing program is well within these limits (discussed in detail in Sections 6.2 and 6.3.1) potential pressure drawdown effects on existing third party GAB wells may not impact on the ability of the aquifer to deliver water to the end of the distribution system (WAP principle 9; discussed in detail in Section 6.4) GDE constraint requiring no wells to be established within 5 km of any mapped GAB springs (WAP principle 12), and a 0.5 m drawdown constraint (WAP principle 13) at the 5 km exclusion zone around mapped GAB springs (discussed in detail in Section 6.3.2) a cumulative drawdown impact assessment constraint of 1 m at the edge of the Southwest Springs Zone (WAP principle 24; discussed in detail in Section 6.3.3) a trigger of 10% drawdown of the aquifer pressure head at a State border (WAP principle 26) due to a take of water, invoking consultation with the other State to assess the application (discussed in detail in Section 6.3.4). 6.2 Far North Water Allocation Plan (WAP) Restrictions on water use managed by the WAP relate to impacts of water use on pressure head in the GAB aquifer. The key management principle applied is to “manage by pressure and allocate by volume” (i.e. manage the volume that produces an acceptable fall in artesian head). Another guiding objective of the Far North WAP is to “ensure petroleum production is not restricted by co- produced water restrictions”. In addition to the EIR required for water management purposes, potential effects on GAB springs are usually considered a Matter of National Environmental Significance (MNES) and would trigger an EPBC referral for Federal environmental approvals if a significant impact
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 46 hydrogeologic is likely. This is addressed by the overall EIR that this hydrogeological report supports (Strike, 2014). 6.3 Groundwater Management Criteria 6.3.1 Sustainable Diversion Limits The Far North WAP has established some allocation limits that are assessed as sustainable, and it also enforces limits on drawdown effects at GDE springs. The sustainable diversion limits that have been established (e.g. 60 ML/d for co-produced water) also allow for significant future increase in water use, subject to conditions that manage pumping via aquifer piezometric levels and spring drawdown constraints rather than by volumes as such. Exceeding the pressure/drawdown constraints would trigger the requirement for an Environmental Impact Report (EIR) to be prepared for the Minister, and management conditions may be imposed prior to issuing a licence. In water balance terms, the sustainable diversion limit of 60 ML/d for co-produced water is about twice the total regional volume co-produced in recent years (25-33 ML/d; DMITRE, 2014) and about twice the historical peak (34 ML/d). When the EIR was being developed, the Strike appraisal program was expected to comprise up to 10 wells extracting at up to 0.24 ML/d per well, totalling 2.4 ML/d (or 440 ML volume over 6 months), which is well within the sustainable diversion limits established by the WAP. The total (10 well) maximum production rate of 2.4 ML/d is 4% of the water allocation plan allowance of 60 ML/day for the petroleum sector (SAALNRM Board, 2009), and could conservatively amount to a total maximum volume of 440 ML over six months, which is just 2% of the annual volume allocated to the petroleum sector (21,900 ML). There is a significant degree of conservatism in this initial water balance assessment. The projected 2.4 ML/d would represent a peak rate, assuming that all wells are pumping simultaneously at maximum rate for the entire 6 months. Actually, the program would initially involve pumping from the two existing wells (Klebb-1 and Le Chiffre-1), and progressive commissioning of offset wells at each site. The program is planned to extend for 6 months, and the co-produced water volumes would actually decrease during this time. Further conservatism is confirmed from early results (to December 2014) of ongoing flow testing at Klebb-1 and Le Chiffre-1. Testing indicates that the wells are co-producing less water than expected when the EIR was developed. Klebb-1 is producing water at 200 bbl/day (32 kL/day), Le Chiffre-1 is producing 1200 bbl/day (190 kL/day), and production has shown rapid declines. The total production rate per site is demonstrably less than 1 ML/day, consistent with principle 17 of the Far North Water Allocation Plan (WAP). This lends a further degree of conservatism to the EIR assessment, which demonstrates that, even using extremely conservative assumptions (e.g. that the water is being extracted directly from the GAB, gross over-estimates of production volumes, etc), potential impacts are not significant in relation to GAB springs and other constraints, and are well within the sustainable extraction settings and constraints established in the Far North WAP. In water balance terms, the appraisal program is clearly well within the established sustainable diversion limits. 6.3.2 Confined Aquifer Pressure and Spring Drawdown Triggers The boundary of PEL 96 extends to the western shore of Lake Blanche, and thus lies just inside the boundary of the Southwest Springs Zone, and within the 5 km exclusion zone around the mapped Lake Blanche spring (Figure 18). The drawdown constraints/triggers established by the WAP are:
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the predicted pressure drawdown of taking water must not exceed 1 metre at the boundary of the Southwest Springs Zone; and the predicted pressure drawdown of taking water must not exceed 0.5 metres at the boundary of a 5 km exclusion zone around any individual spring. Figure 18 shows the alignment of the boundary of the Southwest Springs Zone in relation to PEL 96, along with the 5 km exclusion zone around the Lake Blanche spring. The spring at the north-western end of Lake Blanche is the closest spring to the Klebb and Le Chiffre sites, with the shortest separation distances being from Klebb-1: 47 km to the 5 km spring exclusion zone 41 km to the Southwest Springs Zone. 6.3.3 Cumulative Drawdown Impact Assessment In Appendix 4 of the explanatory notes to the Far North WAP (SAALNRM Board, 2009), a distance-drawdown graph based on the de Glee steady state leaky aquifer equation is provided to estimate the drawdown impacts for varying rates of water use. The de Glee hydrogeological conceptualisation is consistent with GAB and Cooper conditions, although the aquifer parameters assumed for the calculation (as presented in the WAP notes) are very high (i.e. approaching unreasonably high) for the GAB aquifer properties, and the parameters are far too high to be representative of Cooper Basin formations. This is appropriately conservative as it has the effect of over-predicting the regional extent of drawdown impacts. The de Glee parameter values considered in the WAP notes are: Transmissivity: T = 250 m2/d Vertical hydraulic conductivity of the confining layer: Kv = 1.2 x 10-4 m/d Thickness of the leaky layer: b’ = 250 m. The transmissivity value of 250 m2/d is equivalent to 2.5 m/day (or roughly 2500 mD) over a 100 metre thickness of GAB aquifer (i.e. roughly the combined thickness of the main confined aquifer units of the Cadna-owie and Hutton units). If one assumes an entire GAB sequence of about 600 m, a permeability value of 0.4 m/d would be required to achieve a transmissivity of 250 m2/d. This is roughly 400 mD, which is still at the very high end of values for the most permeable Hutton Sandstone units (Table 5). The high transmissivity assumption was considered appropriate at this stage for a highly conservative impact assessment. It will be subject to review as additional data becomes available from the appraisal program. The conservative de Glee parameters listed above were applied along with the following: separation distance of 40 km (i.e. from Klebb to 1 km short of the South West Springs Zone boundary; see Section 6.3.2 and Figure 18) a drawdown constraint of 0.5 metres was applied at this location (i.e. the more constraining spring exclusion zone drawdown condition of 0.5 m was applied at this location, rather than the 1 metre drawdown that actually applies at the Southwest Springs Zone boundary). Application of the de Glee analytical model with these conservative parameter settings allows the calculation of the maximum cumulative pumping rate of about 5 ML/d at a centre of pumping assumed at Klebb-1 (Figure 21). As the projected appraisal testing maximum rate is 0.24 ML/d per well, this prediction allows for up to 20 wells in total at Klebb and Le Chiffre totalling 4.8 ML/d for the appraisal testing, without exceeding the spring drawdown constraints. The de Glee calculations predict a 0.5 m drawdown at the edge of the South West Springs Exclusion Zone (half the 1 m constraint value) due to pumping at 5 ML/day,
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 48 hydrogeologic and the drawdown predicted at the 5 km Spring Exclusion Zone is 0.34 m (two-thirds of the 0.5 m constraint value). Actual plans for the appraisal testing are for less than half of this scale of extraction (a conservative maximum of 10 wells (not all at Klebb) pumping at a total of 2.4 ML/d). It is worth noting again that early results (to December 2014) of ongoing flow testing at Klebb-1 and Le Chiffre-1 indicates that the wells are co-producing less water than expected when the EIR was developed. Klebb-1 is producing water at 200 bbl/day (32 kL/day), Le Chiffre-1 is producing 1200 bbl/day (190 kL/day), and production has shown rapid declines. The total production rate per site is demonstrably less than 1 ML/day, consistent with principle 17 of the Far North Water Allocation Plan (WAP), and the total pumping rate across both sites is expected to be less than 2 ML/day. Sensitivity analysis was undertaken using the de Glee model with a Patchawarra permeability value reported from drilling/testing at the sites of 15 mD (aquifer Kh of 0.01 m/d; see Table 4 and Section 5.5.2) and an aquitard thickness of 50 m (Roseneath and Murteree combined). This results in a predicted total extraction rate of 4.1 ML/d for a drawdown of 0.5 m at the Southwest Springs Zone, consistent with the 5 ML/day predicted for the GAB parameters applied, and more than twice the production rates measured from the highest flow testing rates at Le Chiffre. There is ongoing consultation with DEWNR on the application of a range of parameters to the de Glee analysis, including consideration of timescales involved. There is clearly a significant degree of conservatism (or lack of sensitivity) in this calculation, notably: the appraisal testing is planned for a period of only 6 months, not the long term average assumed for the steady state de Glee method, which over-predicts the drawdown impacts the actual distance from Klebb-1 to the spring exclusion zone is 47 km (not the 40 km assumed above), which increases the allowable maximum total pumping rate to about 7 ML/d (or, assuming a conservative 3 ML/d total rate, it relaxes the predicted drawdown to about 0.3 m, well within the 0.5 m constraint); further reductions in predicted impacts would follow from consideration that only 3 wells are planned for the test at Klebb (the site closest to the spring), that the Le Chiffre site is a further 8 km from the spring, and that ongoing flow testing has confirmed that actual production rates are much lower than initially predicted, amounting to less than 1 ML/day total at each site; the nearest GAB well to the site is the Montecollina Bore, located on the Strzelecki Track 40 km south of the site, which discharges at only 0.15 ML/d; the nearest other GAB wells are stock bores located more than 50 km from the site (i.e. the cumulative volume from the appraisal testing is an appropriately conservative assumption); the appraisal program is testing specific coal units within the 300-400 m thick sequence of the Patchawarra Formation, which is a Permian unit within the Cooper Basin, at a depth of more than 350 m below the Jurassic units of the GAB, and with 16-33 m thicknesses of intervening Permian aquitards (Roseneath and Murteree Shales); the de Glee calculation above conservatively assumes direct and complete hydraulic connection from the pumped unit, effectively assuming that all the extraction is occurring from the GAB aquifers; and Sensitivity analysis with Patchawarra aquifer properties and Roseneath-Murteree aquitard properties results in de Glee predictions of total production of 4.1 ML/d for a drawdown of 0.5 m at the Southwest Springs Zone, confirming the robust conservatism in the calculations.
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Figure 21 - de Glee calculation of steady state drawdown within 0.5 m spring constraint (after SAALNRM Board, 2009)
40 km
0.5m
As the 0.5 m spring constraint is not exceeded at a (conservative) distance of 40 km, it follows that the cumulative drawdown impact constraint of 1 m at the Southwest Springs Zone located at 41 km is also not exceeded. The predicted cumulative pressure drawdown for the multi-well production and appraisal test (under very conservative assumptions) is less than the 0.5 metre trigger level at the edge of the 5 km spring exclusion zone and also less than the 1 m constraint at the edge of the Southwest Springs Zone (see Figure 18). 6.3.4 Drawdown Constraint at SA Border A further restriction imposed by the WAP is that if any take of water results in greater than 10% drawdown of the aquifer pressure head at a State border, then the other State must be consulted in assessing the application. In this case, the border of three States (SA, QLD and NSW) is located about 90 km due east of the Strzelecki Creek that passes between Klebb-1 and Le Chiffre-1. The pressure head at this border location is about 100 mAHD (NWC, 2013, Figure 2.4), which indicates a 10% constraint of 10 m drawdown. Obviously, as this is much greater than the spring drawdown constraint, compliance with the spring constraint in this case ensures compliance with the border constraint. Furthermore, application of the de Glee model with default GAB parameters and 5 ML/day total extraction results in predicted drawdown of 0.038 m at the border, confirming compliance with the border constraint.
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6.3.5 Salt Balance While the WAP provides excellent guidance on water balance issues, it provides no guidance on assessment of salt balance issues. A simple calculation can identify the scale of the salt balance: assuming 0.24 ML/d per well at 5000 mg/L would generate 1.2 tonne of salt per day per well (in simple terms, about 0.5 tonne of salt (about one ute load) per 100 tonne of water produced). Over a period of 6 months and assuming 10 wells, this would amount to about 218 t per well, or about 2180 t in total. Salt management issues are discussed in the EIR (Strike, 2014). In principle, potential impacts are likely to be low level and localised. Any impacts to soil or unconfined groundwater quality in the interdune swale are likely to be very localised and not significant. 6.4 Third Party Issues The highly conservative impact assessment outlined above establishes that the co-produced water volumes are sustainable, and meet the WAP requirements, including the drawdown constraints at GAB springs, which are more than 40 km from the Klebb site. The nearest operational GAB bore is about 40 km from the site and thus any potential impacts due to the proposed appraisal program would not be material. The monitoring and management plan being developed in consultation with DEWNR will include a requirement that any drawdown impact on third party users due to the proposed activity does not affect the ability of the aquifer to deliver water to the end of their water distribution systems. It is also interesting to note the following insights from the GAB Resource Study Update (GABCC, 2010) in terms of the overall potential for the project to impact on existing water users: “There is little immediate scope for conflict between the interests of the rural users of water from the GAB and those of the petroleum sector. As a general rule, petroleum is produced from the GAB at depths greater than 1300 metres — that is, from only the deepest of the aquifers or from those of the upper aquifers that lie below the general economic depth for the drilling of water bores. The combination of these factors means that, with rare exception, there is limited scope for petroleum operations to influence the productivity of nearby water bores through changes in aquifer pressure — they generally do not connect with water-bearing aquifers. In addition, water produced from oil reservoirs can be of poor quality or saline.” 6.5 Hydrogeological Data Gathering and Monitoring A draft monitoring plan has been prepared, and is being used for consultation with DEWNR to develop/refine a detailed monitoring and management plan, with triggers and response actions, consistent with the WAP and IESC requirements. In simple terms, the monitoring plan involves: Collection of aquifer pressure, water production and water quality data for the Patchawarra Formation during the production testing Collection of data on baseline aquifer pressures and water quality in the Hutton during the drilling and appraisal program Collection of unconfined groundwater quality data Collection of detailed hydrochemistry and isotope data from GAB bores and springs GAB spring monitoring Aquifer pressure monitoring in GAB wells Water level monitoring in other non-GAB wells
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Possible conversion of one of the Klebb wells to a GAB monitoring well after the production testing program. The scope and scale of the data gathering and monitoring program will match the PEL 96 project progression. If the project progresses towards a development phase, it is expected that one or more monitoring wells may be drilled into the GAB. The location of any future monitoring bores would need to be carefully considered when further data has been collected, to ensure that they will provide data relevant to the risks that the project may introduce to the area. At this stage it is considered that the site that includes Forge-1 and backfilled bore 6839-10 (see Figure 2 and Figure 18) would be a nominally suitable location. Until such time as new monitoring wells are drilled in optimum locations, it is suggested that the Montecollina bore could be used for GAB monitoring, subject to the owner’s approval, and technical feasbility (noting previous issues relating to inability to obtain shut- in pressures). It is the closest GAB bore to the project sites, and is at almost the same distance (40 km) from the sites as the Southwest Springs Zone boundary (near the Lake Blanche spring). The achievement of environmental objectives could potentially be assessed by monitoring pressure and/or flow at Montecollina regularly (e.g. monthly during the appraisal test).
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The appraisal testing project parameters and predicted hydrogeological impacts have been assessed under a highly conservative set of assumptions as being completely consistent with the requirements of the Far North PWA Water Allocation Plan (SAALNRM Board, 2009), including (see also Figure 18 for locations of spring exclusion zones): highly conservative conceptualisation (e.g. all water production from the Hutton Sandstone not the Patchawarra Formation), conservative aquifer parameter values (representative a high permeability GAB aquifer) and application of the WAP- specified de Glee analytical modelling methodology sensitivity analysis with Patchawarra aquifer properties and Roseneath-Murteree aquitard properties results confirms the robust conservatism in the calculations the water balance assessment considers an appraisal program of up to 10 wells extracting at up to 0.24 ML/d per well, totalling 2.4 ML/d (or 440 ML volume over 6 months), which is 4% of the sustainable diversion limits established by the WAP of (60 ML/d), or 2% of the annual volume allocated to the petroleum sector (21.9 GL/a) ongoing flow testing has confirmed that actual production rates are much lower than initially predicted, amounting to less than 1 ML/day total at each site the water balance assessment conservative assumptions include more wells than are actually planned and that there would be no decline in water production over this period (although this is very likely) the 5 km spring exclusion zone is located at a distance of 47 km from Klebb (the closest site), whereas the predicted 0.5 m drawdown is calculated (using the WAP- specified steady state method) to apply at a distance of just 40 km for an assumed extraction of 5 ML/d (which is more than twice the amount required for the appraisal test) the edge of the Southwest Springs Zone is located 41 km from Klebb, and the cumulative drawdown impact assessment is calculated as 0.5 m at 40 km, well within the 1 metre constraint (assuming 5 ML/d and steady state drawdown) the State border drawdown trigger (10% of the aquifer pressure head) amounts to 10 m at a distance of 90 km, whereas a maximum of 0.5 m drawdown is predicted at a distance of 40 km (i.e. compliance with the spring constraint in this case ensures compliance with the border constraint). The small scale exploration, production testing and appraisal program proposed by Strike will improve the hydrogeological information and reduce uncertainties and data gaps on aquifer inter-connectivity and potential drawdown at GAB springs to the south-west at Lake Blanche. The proposed data gathering during and following the appraisal testing will provide detailed and site-specific data for more detailed assessments in the future. A program for data gathering and future monitoring of hydrogeological parameters will be progressively refined as the project develops, but would nominally involve: Collection of confined aquifer pressure, water production and water quality data for the Patchawarra Formation during the production testing Collection of baseline data on confined aquifer pressures and water quality in the Hutton during the drilling and appraisal program Collection of unconfined groundwater quality data Collection of detailed hydrochemistry and isotope data from GAB bores and springs Possible conversion of one of the Klebb wells to a GAB monitoring well after the production testing program.
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 53 hydrogeologic 8 REFERENCES
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Appendix A - Groundwater Data
61.017.1e_PEL96_Multiwell_ProdTest_Groundwater_20141216.docx 58 Table A.1: Record of bores drilled into the Tertiary/Quaternary units within a 100km radius of the proposed drilling site in PEL 96 (WaterConnect Groundwater Data, 2013)
Record of Tertiary/Quaternary bores located within 100km of PEL 96
SWL RSWL TDS EC Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date Easting (MGA) (m) (mAHD) (mg/L) (μS/cm) (MGA)
6839-2 NL 2.74 12.99 6/06/1940 2470 4429 6/06/1940 399550.43 6764420.21 6839-1 NL 2.59 19.34 6/06/1940 7193 12505 6/06/1940 402553.43 6784782.3 6838-45 Topn NL 3027 5407 1/11/1940 378098.24 6703299.37 6838-15 NL 6875 11997 1/08/1961 398784.52 6724332.36 6738-24 OBS,STK EQP 8.51 36.85 9/10/1979 5784 10133 22/07/1980 350815.35 6729360.2 6839-5 OPR 9170 15767 8/01/1969 354993.39 6765204.21 6839-6 NL 5.49 11.92 12/09/1961 9735 16676 12/09/1961 367901.48 6742497.27 6940-66 13.3 13.3 STK OPR 10.9 17.32 16/06/1994 501 910 30/06/1994 429222.44 6835128.21 6739-3 ABD 9.45 28.22 19/09/1961 1200 2172 2/09/1961 323612.62 6749933.39 6940-162 15 9 11.5 20/04/2012 407320 6824684 6838-8 ABD 12.8 13.94 389148.38 6716859.34 7039-15 18.8 18.8 OPR 13.5 97.64 15/01/1987 4738 8367 15/01/1987 487812.39 6744262.17 6940-2 16.76 OBS OPR 18.29 11.42 4/03/1974 1042 1888 22/07/1980 429124.34 6835134.04 6839-8 19.81 NL 8751 15074 9/11/1960 364873.36 6744638.4 6838-22 Knc DOM,OBS, STK EQP 6.45 81.27 5/04/1978 1676 3020 12/07/1991 377620.45 6690303.26 6841-9 22.86 19.81 OPR 14.63 15.24 21/01/1966 384569.57 6858042.19 6840-12 24.38 22.25 OPR 8.23 14.85 1/04/1968 387316.41 6844622.21 6841-8 24.38 18.9 OPR 5.49 20.72 13/01/1966 379830.59 6855222.2 6841-6 24.38 19.51 OPR 6.1 18.53 9/01/1966 379850.52 6855237.14 6841-7 24.38 18.9 OPR 5.18 21.14 11/01/1966 379827.51 6855227.05 6739-7 ABD 24 -11.02 2/09/1961 11324 19224 12/09/1961 342230.48 6768079.36 6840-11 25.6 23.47 OPR 8.53 14.72 1/03/1968 387321.52 6844630.24 6840-14 26.21 10.05 OPR 10.05 14.62 1/04/1968 387369.42 6844646.1 6739-5 EQP 21 31.58 9/10/1979 1299 2349 12/09/1961 331075.06 6739974.05 6941-24 19.81 OPR 26.52 12.5 4/03/1974 2399 4304 6/06/1961 443629.49 6858540.08 6840-17 27.43 21.33 IND OPR 9.44 27.6 1/03/1968 401008.44 6844038.2 6840-16 29.87 22.55 IND OPR 15.54 18.38 1/03/1968 401071.49 6844069.2 6838-51 Kmb 30.4 24.4 STK EQP 16.2 101.19 5/05/1978 4001 7100 5/05/1978 363128.43 6697911.39 Record of Tertiary/Quaternary bores located within 100km of PEL 96
SWL RSWL TDS EC Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date Easting (MGA) (m) (mAHD) (mg/L) (μS/cm) (MGA)
6940-29 30.48 26.51 OPR 10.66 16.78 1/04/1970 420232.41 6801368.28 6940-30 30.48 23.77 OPR 10.97 16.36 1/04/1970 420235.33 6801368.3 6841-78 31.09 28.34 OPR 8.53 29.27 1/01/1969 385438.49 6854850.34 6841-13 31.39 27.28 OPR 24.38 4.09 25/09/1969 392916.39 6874686.04 6840-15 31.7 22.7 IND OPR 9.44 22.23 1/02/1968 401089.43 6844077 6838-55 TpQaw 32 32 STK OPR 18 29.36 9/08/1989 1564 2820 9/08/1989 392522.39 6684378.35 6841-77 32.61 28.34 OPR 8.53 29.27 1/01/1969 385438.49 6854850.34 6841-80 32.91 19.5 OPR 8.53 26.65 1/07/1970 382654.45 6859129.12 6838-56 Topn 33 33 STK OPR 27 30.2 9/08/1989 4699 8300 9/08/1989 387628.29 6687569.27 6841-74 33.22 30.17 OPR 11.88 25.92 1/12/1968 38075 57534 10/01/1969 385438.49 6854850.34 6838-28 TpQaw STK EQP 18.3 29.06 4/04/1978 1558 2810 4/04/1978 392640.4 6684567.24 6841-79 33.52 25.29 OPR 8.53 23.77 1/07/1970 382625.46 6859138.14 6841-23 33.53 31.37 OPR 21.34 11.39 14/10/1969 400624.57 6873621.09 6939-19 33.8 APN ABD 9.5 19.07 18/10/1996 411822.41 6789778.23 6838-24 Topn STK EQP 24.3 32.9 4/04/1978 1132 2050 4/04/1978 387628.29 6687569.27 6841-63 33.83 32.09 OPR 9.75 13.54 1/02/1968 398596.46 6859439.2 6841-64 33.83 31.39 OPR 9.75 13.23 1/02/1968 398596.55 6859429.12 6841-61 33.83 31.39 OPR 9.75 17.6 1/09/1967 399392.55 6862477.06 6841-84 33.83 31.39 OPR 9.75 15.21 15/09/1968 400665.45 6865498.11 6838-306 34 34 10 97.45 3/09/2008 2069 3720 3/09/2008 358537.9 6702544.05 6841-22 34.14 31.72 OPR 25.91 6.82 16/10/1969 400624.57 6873621.09 6939-11 35 ABD 9.14 12.02 17/01/1968 408673.46 6790271.22 6841-69 35.05 OPR 9.14 20.69 18/06/1981 400300.49 6867798.09 6841-62 35.66 31.39 OPR 9.75 17.46 1/09/1967 399379.48 6862480.04 6841-82 35.66 OPR 9.75 23 4/04/1981 391510.5 6863349.95 6941-85 36 30 OPR 29 3.83 1/02/1978 21600 34700 1/02/1978 422202.54 6877905.1 6940-26 36.37 21.33 OPR 13.71 31.33 26/10/1984 412525.53 6831349.2 6739-12 37 37 STK OPR 21 29.33 22/08/1991 1384 2500 22/08/1991 331330.54 6739477.4 6838-11 OPR 24.99 7.97 21/08/1961 3370 6005 21/08/1961 379289.32 6725561.2 6841-14 39.62 33.07 OPR 25.91 0.2 28/09/1960 392809.51 6874668.12 Record of Tertiary/Quaternary bores located within 100km of PEL 96
SWL RSWL TDS EC Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date Easting (MGA) (m) (mAHD) (mg/L) (μS/cm) (MGA)
6939-14 40 16.8 IND OPR 7.5 12.82 26/05/1991 18028 29500 26/05/1991 412022.37 6771378.23 6838-9 Taee 40.2 40.15 ABD 4212 7466 5/01/1929 378370.04 6710207.05 6940-45 41 36 IND OPR 11 17.08 12/07/1989 17357 28500 16/06/1989 420601.53 6839021.12 6941-74 41 35.6 OPR 14.6 26.59 23/01/1980 26901 32117 23/01/1980 417173.45 6864094.08 6841-68 41.14 24.38 OPR 8.83 18.22 1/06/1972 395867.61 6864381.21 6941-86 42 BKF 23 4.6 3/02/1978 422728.51 6877815.03 6841-71 42.5 38.7 OPR 9.2 22.57 26/09/1984 33050 50547 12/07/1985 394222.65 6862257.9 6841-66 43.28 33.52 OPR 11.88 15.39 1/04/1971 395935.41 6864441.15 6941-226 43.89 BKF 16.45 17.89 1/07/1978 403888.54 6873483.06 6939-9 44.5 BKF 8.53 12.63 13/01/1968 408673.46 6790271.22 6939-10 44.5 38.05 BKF 8.5 12.66 15/01/1968 408673.46 6790271.22 6839-10 46.2 43.3 BKF 19.1 10.63 5/06/1970 388097.53 6781490.37 6841-67 46.33 10.05 OPR 10.05 17 1/04/1971 395867.61 6864381.21 6841-4 46.63 ABD 16.76 11.69 17/12/1965 383204.5 6856356.12 6841-73 46.93 28.65 OPR 8.53 29.27 1/04/1968 53934 81498 3/06/1968 385438.49 6854850.34 6838-47 TpQaw 47.2 STK EQP 34.5 32.81 5/04/1978 1446 2610 5/04/1978 382664.54 6685940.33 6738-73 48 ABD 0 50.97 2/04/1987 353186.5 6731785.34 6838-53 Topn 48 33.86 OPR 14.5 12.43 3/04/1987 9262 15896 3/04/1987 387233.48 6719952.3 6941-227 48.76 44.5 OPR 13.1 23.82 1/07/1978 403812.49 6873462.05 6838-25 Kmb NL 18.29 99.1 21/08/1961 4761 8407 21/08/1961 363128.43 6697911.39 6838-42 48.77 NL 4.88 8.02 17/11/1894 6990 12176 17/11/1994 391879.5 6731396.28 6838-13 Taee 49.6 43.7 STK OPR 0.3 44.89 21/08/1961 3922 6963 6/04/1978 378370.04 6710207.05 6838-23 TpQaw 50.3 50.3 ABD 23.5 43.81 4/04/1978 2019 3630 4/04/1978 382664.54 6685940.33 6838-59 TpQaw 50.5 47.5 STK OPR 36 31.3 25/09/1991 994 1800 25/09/1991 382522.55 6685778.39 6738-70 52.4 49 STK OPR 33.5 58.42 15/12/1984 353524.48 6709490.28 6940-33 53 53 0 23.04 9/09/1987 406578.53 6823766.12 6939-13 55.47 51.81 BKF 17.37 21.66 1/03/1970 429471.37 6789486.13 6838-33 Topn 55.5 55.5 STK EQP 13.32 10.57 4/05/2005 1412 2550 9/11/1976 394888 6704714 6838-27 JK1 55.86 55.86 DOM,STK EQP 3 87.42 5/04/1978 1446 2610 5/04/1978 378060.4 6690737.26 7040-27 55.9 53.3 STK OPR 36.3 27.73 18/06/1994 5338 9390 30/06/1994 467672.33 6820128.03 Record of Tertiary/Quaternary bores located within 100km of PEL 96
SWL RSWL TDS EC Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date Easting (MGA) (m) (mAHD) (mg/L) (μS/cm) (MGA)
6941-235 56.08 45.06 IND OPR 8.23 18.65 12/09/1989 416770.44 6848348.13 7039-17 57 51.1 STK OPR 38 16.57 17/12/1992 5574 9790 21/07/1993 460215.37 6790956.35 6940-75 57.5 54.5 IND 11 20.1 26/08/1996 6832 11900 26/08/1996 434922.3 6808028.04 6838-48 TpQaw STK EQP 14.55 9.34 4/05/2005 1687 3040 4/05/2005 394888 6704714 6939-12 57.91 49.68 BKF 20.42 18.61 1/03/1970 429471.37 6789486.13 6840-18 57.91 32 OPR 10.66 13.2 23/11/1984 39908 57011 23/11/1984 400682.54 6842149.94 7041-249 57.91 53.03 IND UKN 24.38 30.49 1/12/1967 453313.49 6867121.12 7039-9 57.91 STK OPR 38.5 16.07 15/04/1978 460215.37 6790956.35 7039-11 58.83 58.47 NIU 30.48 14.72 4/03/1978 7867 13600 4/03/1978 451585.36 6791827.03 7041-250 59.74 51.81 IND OPR 8.53 46.34 1/12/1967 453313.49 6867121.12 6941-537 60 51 17 10.54 17/11/2008 407593.69 6865648.19 6940-32 60 60 0 27.84 9/09/1987 409133.49 6835154.19 6941-236 60 60 0 37.06 9/09/1987 415982.46 6862249.04 7041-251 60.35 53.34 OPR 24.07 30.8 1/12/1967 453313.49 6867121.12 7041-46 61 56.8 OPR 26.5 20.1 6/02/1979 4595 8120 6/02/1979 469571.42 6853910.03 7040-25 61.1 58.5 STK OPR 47 17.07 27/05/1994 5599 9830 30/05/1994 475624.49 6802254.1 6941-270 61.26 56.03 IND OPR 17.67 15.58 25/04/1990 419194.48 6875662.1 6841-31 62.51 62.51 OPR 19.81 17.59 28/10/1982 399902.64 6861048.09 6841-59 OPR 9.75 17.4 1/09/1967 42000 60000 14/03/1983 399389.62 6862475.14 7040-6 64.31 OPR 48.77 15.3 4/03/1974 475624.49 6802254.1 6838-35 Taee 61.9 59.44 DOM,STK EQP 18.44 22.25 4/05/2005 1962 3530 4/05/2005 395487 6689484 6939-22 65 STK 38.1 11.81 20/09/1997 6619 11530 31/10/1997 451422.39 6749378.19 6939-24 65 53 IND 42 -7.74 7/06/2004 419683.99 6789692.61 7039-20 65.4 62.8 STK OPR 55 24.81 23/05/1994 5338 9390 30/05/1994 476522.52 6790978.16 6941-169 65.53 OPR 17.06 17.99 1/02/1972 430025.51 6877292.07 6838-54 66.6 57.4 OPR 0 55.48 3/04/1987 2773 4960 3/04/1987 364038.36 6724656.17 6941-225 67.05 35.96 OPR 15.85 21.9 1/06/1978 403798.55 6873439.11 6738-75 69 2 BKF 0 87.77 565 1027 20/05/1991 328560.34 6725706.44 6840-25 59 EXP 12 11.93 5/08/2003 397853.64 6807843.89 6938-3 Topn 70.2 69.2 DRY 4.57 11.03 14/08/1961 5340 9397 14/08/1961 407502.37 6692893.29 Record of Tertiary/Quaternary bores located within 100km of PEL 96
SWL RSWL TDS EC Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date Easting (MGA) (m) (mAHD) (mg/L) (μS/cm) (MGA)
6938-5 Topn 71.8 68.7 STK OPR 4.8 10.8 29/07/1985 5377 9454 8/07/1985 407502.37 6692893.29 6838-10 72.73 72.73 DOM,STK EQP 10.66 21.11 2/04/1978 2778 4970 2/04/1978 378774.04 6725199.96 6940-56 73.15 58.67 OPR 20.72 20.04 2/03/1988 439427.57 6845284.21 6941-181 73.61 64.61 OPR 28.95 17.2 26/05/1984 449557.46 6851188.11 6940-64 74.9 72.5 STK OPR 27.6 18.55 12/12/1992 6361 11100 21/07/1993 445892.44 6804777.94 6940-12 75 BKF 16.2 24.32 27/02/1985 9731 16640 4/03/1985 433351.35 6842323 7041-42 75 69.6 OPR 29.2 30.94 14/10/1978 6119 10700 15/10/1978 454955.41 6868872 7039-18 75 72.5 STK OPR 38.8 17.07 24/02/1993 466903.44 6771667.17 7041-38 77.7 71 OPR 34.7 18.46 20/09/1977 6119 10700 20/09/1977 473210.4 6848557.06 6941-171 78.02 74.06 OPR 15.85 18.74 1/07/1962 425169.48 6874104.06 7039-8 78.94 78.2 STK OPR 59.9 8.49 14/04/1978 794 1440 14/04/1978 467181.21 6764129.99 7039-16 79.7 76.9 STK OPR 59.3 18.02 23/02/1993 5569 9780 20/12/1992 471382.35 6762600.06 6940-70 79.9 64.6 IND 7.5 18.6 12/08/1995 15310 25400 12/08/1995 415622.61 6819455.2 6939-15 80 76 IND OPR 4 14.36 1/06/1991 9015 15500 31/05/1991 412022.48 6771578.35 6941-176 80.77 36.27 OPR 15.24 27.74 20/02/1986 411833.5 6866960.12 7039-19 81.6 79 STK OPR 35.2 17.33 6/03/1994 5766 10100 5/05/1994 452327.34 6769615.24 7040-8 81.69 60.96 ABD 75.59 20.16 4/03/1974 7517 13045 1/06/1964 485658.42 6793642.19 7040-4 81.69 81.08 OPR 65.84 19.23 4/03/1974 5227 9202 27/05/1964 485766.5 6807563.19 6939-23 83 STK 29.2 16.73 26/09/1997 6527 11390 31/10/1997 443622.41 6753878.17 6838-32 Taee NL 54.86 14.81 1/08/1961 671 1218 21/08/1961 381912.5 6697651.21 6940-28 83.82 81.07 OPR 21.33 6.98 1/04/1970 420180.51 6801317.17 6940-140 84 77 19 11.91 9/04/2007 432789.27 6843890.25 6938-2 TpQaw 85.04 79 OPR 3.96 11.64 4/04/1978 5312 9348 22/05/1930 407502.37 6692893.29 6940-87 85.34 47.24 EXP 9.14 18.47 6/06/2002 410489.53 6801439.24 6941-224 85.34 OPR 19.81 7.31 21/11/1984 408158.47 6873323.02 6940-44 86 23 IND OPR 10 13.23 5/07/1989 17024 28000 15/06/1989 413563.53 6797454.06 7039-10 86.26 86.26 ABD 75.58 38.87 4/03/1978 492264.3 6791745.08 6940-74 87 82.6 IND 19.5 19.87 22/08/1996 7433 12900 22/08/1996 428422.54 6825328.16 6941-213 87.78 ABD 14.32 17.42 1/02/1973 420527.47 6877088.01 6940-27 88 85 OPR 24 17.06 8/08/1984 429368.3 6827094.04 Record of Tertiary/Quaternary bores located within 100km of PEL 96
SWL RSWL TDS EC Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date Easting (MGA) (m) (mAHD) (mg/L) (μS/cm) (MGA)
7040-29 89 81 IND 2386 4280 29/09/1996 487522.26 6792178.16 7040-14 89.3 86.56 OPR 24.68 15 1/03/1969 453888.44 6829990.07 7040-15 89.91 86.25 OPR 23.77 15.91 1/03/1969 453888.44 6829990.07 7039-7 89.92 3.25 OPR 80.16 25.57 20/04/1963 786 1425 20/04/1963 488232.3 6775085.07 7039-25 90 90 32 18/02/2013 456128.8 6761021.45 6941-496 BKF 23 20.89 4/06/2007 449791.7 6851301.44 7040-26 92 89.5 STK OPR 29 18.43 2/06/1994 4863 8580 30/06/1994 452022.52 6792428.05 6841-58 92.05 ABD 12.8 14.3 1/08/1967 399363.6 6862492.2 6939-3 94.49 ABD 16.15 20.37 17/12/1969 423537.36 6778688.13 7040-45 96 70 31 0.83 1/02/2008 453043.32 6835835.37 6941-542 96 87 42 -4.63 19/11/2007 445353.84 6859960.01 7039-1 97.54 60.63 OPR 73.76 26.34 1/06/1964 5863 10290 1/06/1964 484055.32 6747110.31 7040-5 97.54 OPR 74.98 17.88 4/03/1974 490896.28 6803426.09 6939-2 97.54 ABD 16.15 20.37 10/12/1969 423537.36 6778688.13 6940-31 97.84 70.71 OPR 27.43 18.93 15/06/1984 440005.6 6845301.03 6940-106 100 21.5 EXP 12 14.2 3/08/2003 418769.89 6815980.96 6940-105 100 53 EXP 13 17.22 31/07/2003 419606.13 6800210.02 6941-638 100 83 80 30/04/2008 442982.71 6864541.69 7040-31 102 85 IND 81 31.56 29/09/1996 491622.41 6792728.23 6940-65 105.7 103.1 STK OPR 20.7 25.76 10/06/1994 5633 9890 30/06/1994 450172.31 6817078.1 6941-497 BKF 9.14 21.99 25/06/1991 421857.23 6854482.14 7040-23 106.68 73 IND OPR 76 -32.37 1/01/1965 455947.34 6831357.99 7038-4 106.68 OPR 74.7 17.74 15/01/1987 3846 6830 15/01/1987 490235.32 6724959.11 7040-7 109.73 109.73 IND OPR 79.25 -23.55 4/03/1974 467046.33 6830088.94 6941-40 109.73 109.73 OPR 18.29 12.74 4/03/1974 434187.43 6849517.1 6940-54 110.95 110.95 IND OPR 21.03 20.02 26/06/1989 443521.4 6836659.93 7040-17 111 95 OPR 18 25.28 9/09/1987 454620.39 6842255.17 6838-44 NL 4.27 8.63 20306 32894 391879.5 6731396.28 6838-43 115.82 NL 3.05 9.85 391879.5 6731396.28 7040-32 117 110 IND 5593 9820 3/09/1996 468022.52 6792677.99 Record of Tertiary/Quaternary bores located within 100km of PEL 96
SWL RSWL TDS EC Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date Easting (MGA) (m) (mAHD) (mg/L) (μS/cm) (MGA)
6940-73 120 73 IND 30 15.13 30/08/1996 4946 8720 30/08/1996 447372.46 6793478.09 6838-14 Taee ABD 13.72 20.21 21/08/1961 2044 3677 21/08/1961 388338.38 6714654.17 7040-18 128 ABD 33.5 24.8 9/09/1987 469835.46 6832925.91 7039-6 142.34 89.9 DRY 90.22 22.62 29/09/1959 7193 12505 29/09/1959 494304.25 6752993.07 7040-16 148.44 135.94 STK OPR 89.61 -24.38 31/01/1988 482242.38 6843132.1 6840-9 175 166 OPR 4.3 19.84 24/11/1986 6176 10799 24/11/1986 388831.6 6836609.97 6838-5 124.96 ABD 20 11.77 2/04/1978 3155 5629 2/04/1978 378774.04 6725199.96 Aquifers: Purpose: Status: Knc Cadna-owie Formation APN Anode protection ABD Abandoned OPR Operational Kmb Bulldog Shale DOM Domestic BKF Backfilled UFL Uncontrolled flowing JK-a Algebuckinda Sandstone EXP Exploration DRY Dry UKN Unknown Topn Namba formation IND Industrial EQP Equipped TpQaw Willawortina Formation OBS Observation NIU Not in use Taee Eyre Formation STK Stock NL Not located
Table A.2: Record of bores drilled into the GAB within 100km radius of the proposed drilling locations in PEL 96 (WaterConnect Groundwater Data, 2013)
Record of GAB bores located within 100km of PEL 96
SWL RSWL TDS EC Easting Northing Bore No Aquifer Drilled depth (m) Cased depth (m) Purpose Status WL date Salinity date (m) * (mAHD) (mg/L) (μS/cm) (MGA) (MGA) 6739-6 Knc 283.76 254 CFL -25.89 65.94 18/09/2004 1182 2139 18/09/2004 348521.05 6740716.96 6738-7 289.56 211 CFL 0 95.62 20/09/2000 1452 2620 17/09/2004 344034.01 6711719.02 6838-3 Knc 254 CFL -23.87 74.25 17/09/2004 1832 3300 17/09/2004 362176.04 6719806.03 6838-4 Knc 378.77 270 CFL -25.38 81.24 17/09/2004 1057 1914 17/09/2004 368140 6720406 6838-7 Knc 438.91 119.79 ABD 0 16.73 1/08/1915 12725 21448 1/08/1915 390923.27 6716685.4 6739-10 489 482 STK ABD 0 21.77 18/02/1987 326823.41 6774237.22 6838-6 Kmb 519.1 324.5 CFL -26.64 37.31 17/11/2000 9854 16850 15/10/2012 391596 6731330 6738-189 537 484 MON -21.36 97.03 15/10/2012 992 1797 15/10/2012 347735 6729162 6739-2 Knc 551.68 268.5 STK UFL -29.95 78.82 12/11/2005 1240 2243 18/09/2004 318753.03 6758454.97 6838-29 Knc 596 332 CSH -38.42 88.83 15/10/2012 1479 2670 15/10/2012 390574.97 6694911.99 6739-17 679 610 MON -50.76 97.83 12/11/2005 330366.7 6740404.6 6739-11 Kmb 701 STK BKF -15.17 36.33 21/09/2000 7422 12880 18/09/2004 331528 6773812 7038-1 717.19 ABD 0 63.19 1/01/1924 460795.54 6717344.24 7038-2 JK-a 717.19 300.6 EXP CFL -31.94 101.28 23/03/2013 1743 3140 23/03/2013 461014.72 6717324.96 6839-3 Knc 777.2 248.5 OBS CFL 0 9.25 18/09/1996 5540 9730 17/09/2004 401801.52 6747229.15 7039-4 801.22 NL 17.07 95.06 10/04/1962 1515 2734 2/09/1966 490009.26 6777401.15 6739-16 824 769 MON -80.03 100.56 21/08/2011 326500 6774605 7039-5 JK-a 1100.33 248.5 CFL -9.48 108.54 11/05/2005 1614 2910 11/05/2005 490259.09 6778174.15 Aquifers: Purpose: Status:
Knc Cadna-owie Formation EXP Exploration ABD Abandoned NL Not located Kmb Bulldog Shale MON Monitoring BKF Backfilled UFL Uncontrolled flowing JK-a Algebuckinda Sandstone OBS Observation CFL Controlled flowing STK Stock CSH Controlled - shut in
*negative values represent artesian conditions
Table A.3: Record of bores drilled into the GAB within 25km radius of the proposed drilling locations in PEL 96 (WaterConnect Groundwater Data, 2013)
Record of Tertiary/Quaternary bores located within 25km of PEL 96
Drilled Cased RSWL TDS EC Easting Northing Bore No Aquifer Purpose Status SWL (m)* WL date Salinity date depth (m) depth (m) (mAHD) (mg/L) (μS/cm) (MGA) (MGA)
6939-20 30 30 ETH ABD 412322.4 6787678 6939-21 30 30 ETH ABD 412322.5 6785578 6940-29 30.48 26.51 OPR 10.66 16.78 1/04/1970 420232.4 6801368 6940-30 30.48 23.77 OPR 10.97 16.36 1/04/1970 420235.3 6801368 6939-16 33 5 IND ABD 413811.4 6788739 6939-19 33.8 APN ABD 9.5 19.07 18/10/1996 411822.4 6789778 6939-11 35 ABD 9.14 12.02 17/01/1968 408673.5 6790271 6939-14 40 16.8 IND OPR 7.5 12.82 26/05/1991 18028 29500 26/05/1991 412022.4 6771378 6939-9 44.5 BKF 8.53 12.63 13/01/1968 408673.5 6790271 6939-10 44.5 38.05 BKF 8.5 12.66 15/01/1968 408673.5 6790271 6839-10 46.2 43.3 BKF 19.1 10.63 5/06/1970 388097.5 6781490 6839-11 48.77 44 BKF 388097.5 6781490 6939-13 55.47 51.81 BKF 17.37 21.66 1/03/1970 429471.4 6789486 6939-12 57.91 49.68 BKF 20.42 18.61 1/03/1970 429471.4 6789486 6939-7 64 BKF 411673.5 6790359 6939-8 64 BKF 411673.5 6790359 6939-24 65 53 IND 42 -7.74 7/06/2004 419684 6789693 6940-68 74.3 5.5 IND ABD 414833.5 6794922 6839-9 76 76 ABD 388097.5 6781490 6939-15 80 76 IND OPR 4 14.36 1/06/1991 9015 15500 31/05/1991 412022.5 6771578 6939-17 83 2 IND ABD 411876.5 6784605 6939-18 83 2.5 IND ABD 417727.6 6791388 6940-28 83.82 81.07 OPR 21.33 6.98 1/04/1970 420180.5 6801317 6940-87 85.34 47.24 EXP 9.14 18.47 6/06/2002 410489.5 6801439 6940-44 86 23 IND OPR 10 13.23 5/07/1989 17024 28000 15/06/1989 413563.5 6797454 6939-3 94.49 ABD 16.15 20.37 17/12/1969 423537.4 6778688 6939-2 97.54 ABD 16.15 20.37 10/12/1969 423537.4 6778688 Record of Tertiary/Quaternary bores located within 25km of PEL 96
Drilled Cased RSWL TDS EC Easting Northing Bore No Aquifer Purpose Status SWL (m)* WL date Salinity date depth (m) depth (m) (mAHD) (mg/L) (μS/cm) (MGA) (MGA)
6940-105 100 53 EXP 13 17.22 31/07/2003 419606.1 6800210 6940-69 122 3 IND ABD 412872.4 6801078 Purpose: Status: APN Anode protection ABD Abandoned EXP Exploration BKF Backfilled IND Industrial OPR Operational
False
True3.00 3 Environmental CERTIFICATE OF ANALYSIS Work Order : EM1310344 Page : 1 of 3 Client : STRIKE ENERGY LIMITED Laboratory : Environmental Division Melbourne Contact : MR ANDREW FARLEY Contact : Client Services Address : LEVEL 9, 71 WALKER STREET Address : 4 Westall Rd Springvale VIC Australia 3171 PO BOX 452 NORTH SYDNEY NSW 2060 E-mail : [email protected] E-mail : [email protected] Telephone : +61 02 8261 1020 Telephone : +61-3-8549 9600 Facsimile : ---- Facsimile : +61-3-8549 9601 Project : PEL 96 Water Bores QC Level : NEPM 2013 Schedule B(3) and ALS QCS3 requirement Order number : 1638 C-O-C number : ---- Date Samples Received : 01-OCT-2013 Sampler : Dunns Earthmoving Issue Date : 08-OCT-2013 Site : ---- No. of samples received : 4 Quote number : ---- No. of samples analysed : 4 This report supersedes any previous report(s) with this reference. Results apply to the sample(s) as submitted. All pages of this report have been checked and approved for release. This Certificate of Analysis contains the following information: l General Comments l Analytical Results
NATA Accredited Laboratory 825 Signatories This document has been electronically signed by the authorized signatories indicated below. Electronic signing has been Accredited for compliance with carried out in compliance with procedures specified in 21 CFR Part 11. ISO/IEC 17025. Signatories Position Accreditation Category
Dilani Fernando Senior Inorganic Chemist Melbourne Inorganics
Address 4 Westall Rd Springvale VIC Australia 3171 | PHONE +61-3-8549 9600 | Facsimile +61-3-8549 9601 Environmental Division Melbourne ABN 84 009 936 029 Part of the ALS Group An ALS Limited Company Page : 2 of 3 Work Order : EM1310344 Client : STRIKE ENERGY LIMITED Project : PEL 96 Water Bores General Comments
The analytical procedures used by the Environmental Division have been developed from established internationally recognized procedures such as those published by the USEPA, APHA, AS and NEPM. In house developed procedures are employed in the absence of documented standards or by client request. Where moisture determination has been performed, results are reported on a dry weight basis. Where a reported less than (<) result is higher than the LOR, this may be due to primary sample extract/digestate dilution and/or insufficient sample for analysis.
Where the LOR of a reported result differs from standard LOR, this may be due to high moisture content, insufficient sample (reduced weight employed) or matrix interference.
When sampling time information is not provided by the client, sampling dates are shown without a time component. In these instances, the time component has been assumed by the laboratory for processing purposes.
Key : CAS Number = CAS registry number from database maintained by Chemical Abstracts Services. The Chemical Abstracts Service is a division of the American Chemical Society. LOR = Limit of reporting ^ = This result is computed from individual analyte detections at or above the level of reporting l EA016: Calculated TDS is determined from Electrical conductivity using a conversion factor of 0.65. l Ionic Balance out of acceptable limits for sample #1 and #4 due to analytes not quantified in this report. l Ionic balances were calculated using: major anions - chloride, alkalinity and sulfate; and major cations - calcium, magnesium, potassium and sodium. Page : 3 of 3 Work Order : EM1310344 Client : STRIKE ENERGY LIMITED Project : PEL 96 Water Bores Analytical Results
Sub-Matrix: WATER (Matrix: WATER) Client sample ID Klaus Bore Maslins Bore Bobs Bore Strez Bore ----
Client sampling date / time 20-SEP-2013 15:00 21-SEP-2013 15:00 21-SEP-2013 15:00 22-SEP-2013 15:00 ----
Compound CAS Number LOR Unit EM1310344-001 EM1310344-002 EM1310344-003 EM1310344-004 ---- EA005P: pH by PC Titrator pH Value ---- 0.01 pH Unit 8.00 7.50 7.16 6.97 ---- EA006: Sodium Adsorption Ratio (SAR) Sodium Adsorption Ratio ---- 0.01 - 35.5 49.6 44.8 43.3 ---- EA010P: Conductivity by PC Titrator Electrical Conductivity @ 25°C ---- 1 µS/cm 18300 34600 16700 29600 ---- EA016: Non Marine - Estimated TDS Salinity Total Dissolved Solids (Calc.) ---- 10 mg/L 11900 22500 10800 19200 ---- EA065: Total Hardness as CaCO3 Total Hardness as CaCO3 ---- 1 mg/L 1730 3110 1370 2930 ---- ED037P: Alkalinity by PC Titrator Hydroxide Alkalinity as CaCO3 DMO-210-001 1 mg/L <1 <1 <1 <1 ---- Carbonate Alkalinity as CaCO3 3812-32-6 1 mg/L <1 <1 <1 <1 ---- Bicarbonate Alkalinity as CaCO3 71-52-3 1 mg/L 201 115 119 117 ---- Total Alkalinity as CaCO3 ---- 1 mg/L 201 115 119 117 ---- ED041G: Sulfate (Turbidimetric) as SO4 2- by DA Sulfate as SO4 - Turbidimetric 14808-79-8 1 mg/L 2810 3560 1890 3900 ---- ED045G: Chloride Discrete analyser Chloride 16887-00-6 1 mg/L 5070 10200 4970 8640 ---- ED093F: Dissolved Major Cations Calcium 7440-70-2 1 mg/L 333 525 303 618 ---- Magnesium 7439-95-4 1 mg/L 218 437 148 336 ---- Sodium 7440-23-5 1 mg/L 3390 6360 3810 5390 ---- Potassium 7440-09-7 1 mg/L 32 30 22 28 ---- EG052F: Dissolved Silica by ICPAES Silicon as SiO2 14464-46-1 0.1 mg/L 24.8 47.6 18.1 81.0 ---- EK040P: Fluoride by PC Titrator Fluoride 16984-48-8 0.1 mg/L 0.5 0.4 0.7 1.0 ---- EN055: Ionic Balance Total Anions ---- 0.01 meq/L 206 364 182 327 ---- Total Cations ---- 0.01 meq/L 183 340 194 294 ---- Ionic Balance ---- 0.01 % 5.86 3.51 3.09 5.43 ----
Address: 53, Lavinia Street, Athol Park, SA 5012. SA Analytical Laboratory Services Pty Ltd
Postal Address: PO Box 222 ABN: 36 132 336 906 Kilkenny SA 5009 Phone :(08) 83412533 Fax: (08) 83410345
Certificate of Analysis
Client: Strike Energy Client Code: Attention: Chris Hindmarsh Order No: Ph: +61 7 3505 4527 /+61 408 722 859 Address: PET 96 Joint Venture 120B Underwood Street, Paddington NSW 2021
Sample: Water Sample Details: Klebb Bore
Date of Collection: 10.06.2014 Time:
Received in Laboratory on: 10.06.2014 Sample temperature on arrival: 20.0 °C
Test initiated on: 10.06.2014
Sample tested as received in the Laboratory. Results are representative only of the sample portion submitted.
Laboratory Number: 14060215
Chemical Test Results Method Specific Gravity 1.0098 VL 409 Barium - Total 0.1274 mg/L TIC-006 W09-023 Calcium 261 mg/L TIC-004 W09-023 Iron 22.00 mg/L TIC-006 W09-023 Magnesium 164 mg/L TIC-004 W09-023 Potassium 20.8 mg/L TIC-004 W09-023 Sodium 4610 mg/L TIC-004 W09-023 Sulphur 1440 mg/L TIC-004 W09-023 Total Hardness as CaCO3 1330 mg/L TMZ-M06 W09-023 Chloride 6760 mg/L T0104-02 W09-023 Alkalinity as Calcium Carbonate 177 mg/L T0101-02 W09-023 Bicarbonate 216 mg/L T0101-02 W09-023 Carbonate 0 mg/L T0101-02 W09-023 Hydroxide 0 mg/L T0101-02 W09-023 Conductivity 19900 µScm T0016-01 W09-023 Total Dissolved Solids (by EC) 12000 mg/L T0016-01 W09-023 pH 7.5 pH units T0010-01 W09-023
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Address: 53, Lavinia Street, Athol Park, SA 5012. SA Analytical Laboratory Services Pty Ltd
Postal Address: PO Box 222 ABN: 36 132 336 906 Kilkenny SA 5009 Phone :(08) 83412533 Fax: (08) 83410345
Certificate of Analysis
Client: Strike Energy Client Code: Attention: Chris Hindmarsh Order No: Ph: 0408 722 859 PET 96 Joint Venture 120B Underwood Street, Paddington NSW 2021
Sample: Water - Le Chiffre Bore Batch Code:
Date of Collection: 04.06.2014 Time:
Received in Laboratory on: 05.06.2014
Test initiated on: 05.06.2014 Sample temperature on arrival on Laboratory is 3.2°C
Sample tested as received in the Laboratory. Results are representative only of the sample portion submitted.
Laboratory Number: 14060136 Test Result Method Specific Gravity 1.0074 VL409 Barium 0.0434 mg/L TIC-006 W09-023 Calcium 257 mg/L TIC-004 W09-023 Iron 2.187 mg/L TIC-006 W09-023 Magnesium 133 mg/L TIC-004 W09-023 Potassium 25.8 mg/L TIC-004 W09-023 Sodium 3200 mg/L TIC-004 W09-023 Sulphur 1450 mg/L TIC-004 W09-023 Total Hardness as CaCO3 1190 mg/L W09-023 Chloride 4320 mg/L TIC0104-02 W09-023 Alkalinity as Calcium Carbonate 156 mg/L TIC0101-02 W09-023 Bicarbonate 190 mg/L W09-023 Carbonate 0 mg/L W09-023 Hydroxide 0 mg/L W09-023 Conductivity 14700 µScm T0016-01 W09-023 Total Dissolved Solids (by EC) 8500 mg/L T0016-01 W09-023 pH 7.5 T0016-01 W09-023
Name: Shyamlal.K.S. Microbiologist Date: 13.06.2014
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WATER TYPE CATEGORISATION 100 100 Tertiary GAB
80 80 90 90
Cl + SO4 Ca + Mg Cooper Montecollina 60 50 60 50 Cl + SO4 Ca + Mg
40 10 40 10
10 10 20 20
50 50 0 0 Mg
0 0 Mg type Na + K HCO3+CO3 SO type 4 SO4 50 50 50 No 50 No 90 90 dominant dominant 20 20 type type Ca type Na or K type HCO3 type Cl type
100 0 40 0 100 40 50 50 Ca Cl
80 20 20 80 60 60 HCO +CO Na + K 3 3 WATER TYPE SUB-FIELDS Mg 60 40 40 60 80 80 SO4 40 Ca + Mg, Na + K type Ca + Mg type 60 60 40 100 100 20 20 HCO , Cl + SO type HCO + CO type 80 80 3 4 3 3
00 80 100 100 0 Na + K, Ca + Mg type Na + K type 10 60 40 20 0 0 20 40 60 80 100 Ca Cl Cations Anions Cl + SO4, HCO3 type Cl + SO4 type
Piper Diagram
Date: 29/09/14 Project: PEL 96 Appraisal Program 2014 Description: Hydrogeological Assessment
E:\HGL\61\017_Strike\300\310_Analysis\[PEL96 HydroCHEM_25sep.xls]PIPER Project No: 61.017 Client: Strike Energy