APPENDIX I: WATER LEVEL REVIEW, SURAT NORTH STUDY AREA · Appendix I ‐ Water Level Review, Surat North Study Area QGC Page 5 of 18 Figure I.3 ‐ MGPP pressures at Phillip 5 Pressures

Surat North – Water Monitoring & Management Plan

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APPENDIX I: WATER LEVEL REVIEW, SURAT NORTH STUDY AREA

Appendix I ‐ Water Level Review, Surat North Study Area

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APPENDIX I. WATER LEVEL REVIEW, SURAT NORTH STUDY AREA

I.1 Water level review

The following section describes water level data collected since onset of the project and how this relates to the Conceptual Model of groundwater flow and connectivity. The monitoring network includes a number of nested sites where long term monitoring and/or responses to stress through production testing have provided significant insights into connectivity between formations. Locations are shown on Figure I.1.


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Figure I.1 ‐ Study Area groundwater monitoring bore locations


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I.1.1 Peebs block

The Peebs location monitors background groundwater pressures close to the groundwater divide between the northerly flowing system beneath the Dawson Valley and the generally southerly flowing system within the Condamine‐Balonne catchment. Ground level is around RL 375 m, whereas the ground elevation at the MGPP at Phillip 5 is approximately 97 m lower at around RL 279 m.

At Peebs groundwater pressures are monitored in the Gubberamunda (bore GW17) and Springbok Sandstones (bore GW18) in separate bores, whilst a MGPP system (refer Section Error! Reference source not found. for details) has been installed in a purpose‐drilled monitoring bore at Peebs GW16 to monitor various units of the WSG as outlined in Table I.1.

Table I.1 ‐ Groundwater Pressures in Multi Gauge Packer Piezometers Peebs and Phillip Blocks

Multi gauge Installation

Formation Date Ground Level (RL m AHD)

Gauge Depth (m bgl)

Depth to Water (m)

Groundwater Head (RL m AHD)

Peebs GW17 Gubberamunda 30/11/2015 375.37 91.81 62.90 313.98

Peebs GW18 Springbok 30/11/2015 375.40 101.85 75.78 301.65

Peebs GW16 Upper Juandah 01/12/2015 375.38 401.28 68.91 306.47

Lower Juandah 01/12/2015 375.38 489.03 45.68 329.70

Tangalooma Sandstone 01/12/2015 375.38 538.66 45.43 329.93

Taroom Coal Measures 01/12/2015 375.38 596.68 45.55 329.83

Phillip 5 Upper Juandah 03/12/2015 278.73 137.66 21.20 257.53

Lower Juandah 03/12/2015 278.73 261.12 25 253.73

Taroom Coal Measures 03/12/2015 278.73 534.4 8.90 269.83

Hutton 03/12/2015 278.73 666.13 ‐3.01 281.74

Groundwater pressure data from November/December 2015 indicates that pre CSG production groundwater pressures are lowest in the Springbok (RL 301.65) and Upper Juandah (RL 306.47) and highest in the Lower Juandah, Tangalooma and Taroom formations at around RL 330 m. Pressures in the Gubberamunda are higher than in the Springbok, suggesting a downward pressure gradient between these two aquifers, which is the opposite of what is observed in the CDA/SDA where Gubberamunda pressures are generally lower than in the Springbok. MGPP groundwater pressures are shown at Figure I.2.


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Figure I.2 ‐ MGPP pressures at Peebs GW16

I.1.2 Phillip block

The Phillip location will initially monitor background pressures to the south of the sub‐cropping Upper and Lower Juandah formations of the WSG, and over time will monitor pressure changes with the development of the Surat North gas fields. Initial data from early December 2015 indicates an upward pressure gradient from Hutton Sandstone to Lower Juandah. Observed pressures are stable as expected. Hutton pressure (approximately RL 282) is slightly artesian and is showing regular daily oscillations of about 0.5m which may be indicative of a barometric pressure response or unknown private Hutton groundwater extraction. The Hutton pressure at Phillip is the highest observed in the Approval Area and is consistent with previously inferred Hutton pressure distributions in the region.


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Figure I.3 ‐ MGPP pressures at Phillip 5

Pressures in the Upper Juandah at Phillip 5 (RL 258) are marginally higher than groundwater levels measured to the north in shallow Walloon Subgroup bores on the neighbouring Taroom Coal Project of around RL 247.4 on Charlie block (for Taroom Coal groundwater data refer to Appendix D.)

Groundwater pressure response in the WSG at Phillip 5 would suggest that no pressure response to CSG extraction on Kathleen block has been observed to date. Phillip 5 is approximately 10 km to the north of the Kathleen gas field.

I.1.3 Ross

Groundwater pressure response to extraction in the WSG has been measured on Ross block at VWP Ross 6M. Figure I.4 shows the pressure response in the Lower Juandah Argyle seam gauge which indicates a pressure decline of about 18m between July and November 2015.


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Figure I.4 ‐ Groundwater Pressure Response Argyle Seam Walloon Subgroup Ross 6M

I.1.4 Woleebee Creek

Multi – formation pressure response to CSG water extraction continues to be monitored at the Woleebee Creek site. Woleebee Creek GW9 monitors the Springbok Sandstone and groundwater level data is presented in Figure I.5. The data indicates that groundwater pressures proximal to the bore in the low permeability Springbok Sandstone are still equilibrating and have not been influenced by CSG extraction. The most recent recorded pressures of around RL 277.8 m are inferred to be close to background pressure based on earlier Springbok pressure data from VWP Woleebee Creek 17M which recorded stable background pressures from three gauges between RL 275 and RL 285 m AHD (QGC, 2014).

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Figure I.5 ‐ Woleebee Creek GW9 Springbok Hydrograph

1. Eurombah Formation

Groundwater pressures in the Eurombah Formation were monitored with a single gauge Phase 2 bore from July 2012 to June 2015. Following drilling the wellbore took a long time to equilibrate with the formation due to the low permeability of the aquitard material. The pressure remained relatively stable ranging from approximately 355.8 mAHD to 356.3 mAHD. A series of declines of 0.5 m or less occurred from July to November 2012, from June 2012 to July 2013 and from February 2015 to June 2015, after which the gauge was removed and the bore re‐completed as a MGPP, including a gauge to monitor the Eurombah Formation.

2. Hutton Sandstone

Groundwater pressures in the Hutton Sandstone were relatively stable at around RL 263.8 ‐ 263.9 until June 2015. From about February 2015 until the workover in June 2015 the water level in the bore declined by approximately 0.3 m (Figure I.6). Following the workover, the pressure has increased slightly. It is possible that the change from a 280 m thick open hole section of Hutton Sandstone, down to an available thickness of only the upper 40 m of the Hutton has altered the pressure response in the monitoring data. The measurements prior to June 2015 would represent the entire bulk pressure of the Hutton, including any regional declines from 3rd party Hutton groundwater use.

274.0274.5275.0275.5276.0276.5277.0277.5278.0278.5279.0279.5280.0

Jul 2013 Oct 2013 Feb 2014 Jun 2014 Oct 2014 Feb 2015 Jun 2015 Oct 2015

Water Level (m

AHD)

WCK GW9 Water Level

Ground level is 364.9 mAHD


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Figure I.6 ‐ NDA Hutton Groundwater Pressure and Water Production Woleebee Creek block

I.1.5 Juandah Community Bore

The Juandah Community Bore RN 15833 is located on the eastern side of the Polaris and adjoining Acrux gas fields, and is approximately 25 km to the north‐east of WCK_GW3 and 22 km south east of CHL_GW1. QGC is monitoring the groundwater level within this bore as part of QGC’s Make Good obligations under the Water Act and the data have been used to produce a hydrograph in Figure I.7.

Water production commenced on Polaris and Acrux blocks in September 2014 and January 2015 respectively and approximately 144 ML has been extracted from 18 wells that are within 2 km of the bore by October 2015.

DNRM records indicate that the bore is 686 m deep, and constructed with a cement seal to 154 meters below ground, followed by casing in an open annulus through strata inferred to be the WSG and down into the Hutton Sandstone, with perforated casing within the Hutton Sandstone. These records suggest the Juandah bore comprises an open conduit between the WSG and the Hutton Sandstone. The bore has an annual allocation from DNRM to extract 100 ML (approximately 275 m3/day) for stock and intensive stock and is pumped regularly (weekly or more) for short durations of 1 to 2 days to supply water to up to 6 properties. Discharge rates have been reported up to 3.5 L/s or 302 m3/day. The regular drawdown from pumping and subsequent recovery cycles is clearly visible on the hydrograph. Following each pumping event the Hutton groundwater level has continually recovered to the pre‐pumping level at approximately 60 meters below ground (~RL 237.3m) and no long term decreasing or increasing trend in groundwater level is evident

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throughout the period of monitoring. In other words, no pressure reduction due to CSG extraction has been observed at this bore.

Figure I.7 ‐ Juandah Community Bore Hydrograph Feb 2014 to Oct 2015

I.1.6 MNES Monitoring Bores

Charlie Block

1. Hutton Sandstone GW1

Groundwater pressure in the Hutton Sandstone at Charlie GW1 is sub‐artesian and has been monitored since early 2014. The bore shows minor fluctuations of around 0.1m and is relatively stable at around RL 245.3 m AHD Figure I.8.

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Figure I.8 ‐ Charlie GW1 Hutton Sandstone Hydrograph

2. Precipice Sandstone GW2

Groundwater pressure in the Precipice Sandstone at Charlie GW2 is artesian and has been monitored since early 2014. The bore has shown variable periods of pressure increase since September 2014

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Figure I.9.

There are likely to have been multiple factors influencing the timing and rate of pressure increase including possibly:

March 2014 to June 2014 – Recovery following summer 2014/15 agricultural usage from private Precipice bores in the region, including RN 58850 located approximately 5 km to the east;

June 2014 to March 2015 – Recovery following reduction of Precipice construction water usage at Woleebee Creek bore GW4, approximately 29 km to the south;

Post February 2015 – Pressure build‐up following commencement of large‐scale reinjection activities by APLNG in February 2015 at Reedy Creek, approximately 45 km to the southwest.


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Figure I.9 ‐ Charlie GW2 Precipice Sandstone Hydrograph

Charlotte Block


Whilst Woleebee Creek GW3 and Charlie GW1 measure fairly stable groundwater pressures, bore CHR‐GW1 on Charlotte block, which is approximately 23 km north of bore CHL‐GW1 on Charlie block, indicates that a steady decline in groundwater levels of 3.5 m has been observed between September 2013 and June 2015, see Figure I.10. The continuing decline in pressure can be attributed to local private groundwater usage in the Hutton Sandstone (QGC, 2014) for irrigation, stock watering and domestic use. 9 bores have been identified within a 12 km radius of Charlotte GW1, including two bores each with a DNRM annual allocation of 24 ML.

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Pressure recovery period post GW4 extraction


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Figure I.10 ‐ Charlotte GW1 Hutton Sandstone Hydrograph

2. Precipice Sandstone

Precipice bore CHR_GW2 on Charlotte block is also artesian, with a positive head of about 8 m (12 psi) in November 2015. Groundwater pressure was relatively constant at around RL 280.5 m from September to December 2013, suggesting it was not affected by seasonal water extraction for stock watering by private landholders during that time. The bore was out‐of‐service between November 2013‐May 2015 due to a faulty pressure gauge and workover rig unavailability.

Charlotte GW2 was worked over in May 2015 and gauges upgraded, with the subsequent groundwater recovery visible on the hydrograph. The differences in pre‐ and post‐bore workover groundwater pressures may be due to:

Errors in recorded gauge placement depths

Influences of local Precipice bore use. The nearest Precipice bore RN 58022 is approximately 1.4 km away.

Groundwater pressure recovery may also be due to APLNG reinjection activities.

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CHR GW1 Water Level Manual Measurement



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Figure I.11 ‐ Charlotte GW2 Precipice Sandstone Hydrograph

Coochiemudlo Block


Coochiemudlo GW1 bore was drilled to a total depth of 280 m and has shown a small continuous groundwater head decline of around 0.4 m over 2 years from November 2013 to November 2015 (Figure I.12) . There are numerous Hutton private bores within 5 to 10 km of the bore. As the Hutton Sandstone outcrops in the area, the Hutton is the shallowest aquifer and therefore most economical drilling target for stock or domestic supply.

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Water Level (m

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Ground level is264.8 m AHD


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Figure I.12 ‐ Charlotte GW1 Hutton Sandstone Hydrograph

2. Precipice Sandstone GW2

The monitoring bores on Coochiemudlo block are located southeast of Taroom in an area where the Hutton and Precipice Formations are shallower than further to the west and represent an area of groundwater discharge from the Precipice to the Dawson River. Bore CMO_GW2 has exhibited three separate trends in an overall decline in groundwater head of around 2 m over the period April 2013 to May 2014, see Figure I.13. The steepest decline occurred between mid‐September 2013 and late March 2014 and may correspond to the local irrigation season, combined with Precipice extraction from the Taroom town supply bore located approximately 19 km to the northwest.

Since February 2014, groundwater pressures have fluctuated between RL 244.5 and RL 245 m AHD.

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CMD GW1 Water Level



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Figure I.13 ‐ Coochiemudlo GW2 Precipice Sandstone Hydrograph

Connectivity Pilots (Woleebee Creek)

The Woleebee Creek pilot comprised of up to 4 CSG production wells pumping simultaneously, with pressure monitored in both the Walloon Subgroup and other formation. The intent was to introduce a stress to the Coal Measures and monitor for any propagation of drawdown into adjoining formations. This was one of three production tests carried out as part of QGCs connectivity program.

Water production, water pressure, formation thicknesses and hydraulic properties were incorporated in a 2D analytical simulation of leakage from the Hutton Sandstone, upwards through the Eurombah Formation and into the Walloon Sub group over a 1 year period. The vertical hydraulic conductivity (Kv) of the Eurombah Formation was calibrated as 5 x 10‐7 m/d, based on groundwater head measurements in WCK_GW3. From the pressure differential at the end of the simulation, this Kv represents a flux per area of 7 X 10‐7 m3/m2/d and can be considered as a leakage rate of approximately 0.3 mm/yr. This groundwater flux from the Hutton Sandstone upwards through the Eurombah Formation represents a very low rate of groundwater flow.

Groundwater Pressures Walloons Subgroup

Baseline groundwater pressure data from the recently completed MGPP installations at Peebs GW16 and Phillip 5, support the previously developed conceptual groundwater flow model in the Study Area, ie topographically controlled regional groundwater flow from south to north and in a general up‐dip direction, with pressures generally higher in deeper formations.

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Private bore baseline data in the areas of Walloon subcrop (Upper Juandah and Lower Juandah) have been reviewed and indicate that groundwater pressures in some Walloon Subgroup bores on Borrowdale, Golden Grove, Bloodworth, and Charlie blocks are artesian and gassy.

At Phillip 5, pressures in the Upper Juandah (RL 258) are marginally higher than groundwater levels measured in shallow Walloons bores on the Elimatta Coal Project, 4 km to the north of around RL 250.

Groundwater pressure response to extraction in the WSG has been measured on Ross block at VWP Ross 6M, where a pressure decline of about 18m has been inferred between July and November 2015.

Groundwater pressure response in the WSG at Phillip 5 would suggest that no pressure response to CSG extraction on Kathleen block has been observed to date. Phillip 5 is approximately 10 km to the north of the Kathleen gas field.

The observed groundwater pressures are consistent with observed groundwater pressure responses in the CDA and SDA considering the period of extraction in the NDA to date. It could be expected that a regional pressure response (predominantly in the Taroom Coal Measures) to QCLNG extraction to date could be limited to less than a few kilometres, around existing production areas.

Groundwater Pressure Overlying Formations

Groundwater pressures in Springbok bore GW9 are still recovering following bore construction. There is no evidence of pressure depletion due to CSG water extraction at this location.

Groundwater Pressure Underlying Formations

Based on the groundwater pressure response data collected to date from bores completed in the Hutton and Precipice Formations, the following conclusions can be drawn:

Agreement with previous research which suggests the groundwater in the Hutton and Precipice Sandstones on the southern side of the Dawson River catchment generally flows in a north‐easterly direction (Hodgkinson 2010) towards the Dawson River;

Discharge is likely towards the location of the Boggomoss/Dawson River springs area;

Groundwater pressures in the Precipice Sandstone are 20 ‐ 40 m higher than in the Hutton Sandstone apart from at Woleebee Creek where head in the Hutton is slightly higher than the Precipice.

On Woleebee Creek block, Hutton bore WCK_GW3 has a relatively stable hydrograph which shows minimal if any pressure response to the CSG water extraction from pilot testing that has occurred on Woleebee Creek and adjacent blocks to date.

No pressure depletion has been observed in the Juandah Community bore which intersects Walloon Subgroup and Hutton Sandstone on Polaris block.


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MNES Early Warning and Trigger Monitoring Bores

MNES early warning and trigger monitoring bores continue to measure baseline pressures in both Hutton and Precipice Sandstones. No evidence of pressure declines due to the influence of CSG water extraction has occurred.

At some locations groundwater pressures in both formations are influenced by local groundwater extraction, either on a seasonal or continuous basis as indicated by hydrographs in bores CHR_GW1 (Hutton Sandstone ‐ Charlotte block) and CMO_GW2 (Precipice Sandstone ‐ Coochiemudlo block) respectively;

Elsewhere stable hydrographs showing little or no pressure decline with time occur in both formations. This is either due to geological isolation of the bore or where bores are distant from private landholder or other pumping or reinjection influences;

Groundwater pressure in the Precipice Sandstone on Charlie block at CHL_GW2 shows an ongoing pressure rise which is likely due to APLNG groundwater reinjection activities at Reedy Creek, approximately 45 km to the southwest.

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APPENDIX I: WATER LEVEL REVIEW, SURAT NORTH STUDY AREA · Appendix I ‐ Water Level Review, Surat North Study Area QGC Page 5 of 18 Figure I.3 ‐ MGPP pressures at Phillip 5 Pressures