Well Stimulation Activities and the Characterisation of Stimulation Fluids 178

177

11.0 Well stimulation activities and the characterisation of stimulation fluids 178

11.0 Well stimulation activities and the characterisation of stimulation fluids

# Department Condition Description Completion date Status

Pre-Dec 2012 Post-Dec 2012

October 2013 and 37 Annual update of bores to be stimulated 49e 53B c annually thereafter 38 Submission of reports to Queensland regulatory agencies As required 39 Ecotoxicity Work Program Development April 2013 Toxicity and Ecotoxicity Profiles for new chemicals. Completion of total toxicity and ecotoxicity testing. 40 Ecotoxicity testing to be carried out in accordance with the 2000 December 2013 49f 53B c NWQMS Australian and New Zealand Guidelines for Fresh and Marine Water Quality. Collection of representative samples of flow back water 41 Ongoing immediately post-stimulation and analysis Preparation of Stimulation Fluids Risk Assessment incorporating 60 53B c February 2014 results of Hazard Characterisation (DTA)

Commitments completed Evergreen Commitments Commitments work in progress Firm deliverables for that month

Condition 53B(b) replaces Condition 49F of the Stage 2 WMMP

11.1 INTRODUCTION

Application of hydraulic well stimulation techniques can increase CSG production from low-yielding and otherwise uneconomic wells. The objective is to enhance coal seam openings to increase the pathways for gas to flow. For the QCLNG project, stimulation activities are undertaken in the Walloon Coal Measures, normally at depths of greater than 400 m. Pre-stimulation risk assessments identify any potential impacts on the water environment and pre and post-stimulation monitoring is focused on any impact that may be occurring. The potential impact of stimulation fluids on freshwater biota is addressed through direct ecotoxicity testing.

QGC provided a detailed outline of its approach to management and monitoring of hydraulic well stimulation in the Stage 2 CSG WMMP. Information was provided on: • Details of well stimulation activities in 2011 and 2012 and estimates of the number of well stimulations in 2013 and 2014. An update is provided in Section 11.3; • Details of stimulation fluid constituents and stimulation fluid chemical selection; • Toxicological and ecotoxicological information for stimulation chemicals; • Stimulation water management; • Stimulation fluid chemistry and water monitoring data; • Pre-stimulation and post-stimulation water quality data and assessment; and • A qualitative groundwater and surface water quality risk assessment.

For completeness Chapter 13.0 Well Stimulation from the Stage 2 CSG WMMP has been included as an appendix (Appendix M) to this Plan.

For the Stage 3 WMMP, QGC has: • Provided an update of planned stimulation activities for 2013/2014; and • Outlined a program of ecotoxicity hazard assessment and associated risk assessment. 179

11.2 BACKGROUND SUMMARY

Well stimulation techniques can increase CSG production from low yielding or otherwise uneconomic wells. The objective of hydraulic well stimulation is to enhance openings in the coal and increase the pathways for gas to flow. For the QCLNG project, stimulation activities are undertaken in the Walloon Coal Measures (WCM) and normally occur at depths greater than 400 m. QGC's stimulation monitoring and management process includes the use of a range of diagnostic tools to measure hydraulic fracture stimulation performance, such as: • Production logging tools; • Temperature surveys; • Production testing and sampling; • Tracers to measure extent of the fracture; • Microseismic wells which register ground vibration; and • Tiltmeter arrays to measure ground movement.

Typically fracturing of coal seams in the WCM has an estimated fracture height range of between 0 and 40 m and an estimated average lateral extent of approximately 100 m. Due to the depth of stimulation activities in the WCM, limited coal thickness and extent, estimated height and extent of fractures and the stimulation fluid water quality, there is considered to be little risk of contamination of other geological formations and negligible risk of contamination of surface waters. For a hydraulic fracturing event, water quality is assessed in the well and flowback waters. Monitoring of active landholders' groundwater bores (subject to access being permitted by the landholder) may be monitored under certain Queensland government EA conditions. These are for the cases where: • Active landholders' groundwater bores are located within a 2 km horizontal radius from the location of the stimulation initiation point; • Active landholders' groundwater bores are within 200 m vertically of the stimulation initiation point; and • Any other bore that could potentially be adversely impacted by the stimulation activity in accordance with the findings of the risk assessment.

This monitoring occurs at a frequency of monthly for the first six months and then annually for another five years in accordance with DEHP EA conditions. Note no situation has arisen to date where private landholder bore monitoring has been necessary.

11.3 QGC STIMULATION PROGRAM

QGC reports details of its well stimulation program, covering completed activities and wells listed for possible stimulation in the year ahead. QGC's current and short term stimulation program for the Surat Basin is focused on trialing, developing and optimising stimulation techniques prior to full scale stimulation activities commencing. This is not expected to occur until 2018. Consequently, in calendar year 2012, four well stimulations were completed (refer Table 11-1). A total of eight well stimulations have been completed for the 2013 program as shown in Table 11-1. Locations are shown at Figure 11-1.

The indicative stimulation program for 2014 could consist of up to 33 wells with 13 wells in the Northern Development Area and 20 wells in the Southern Gas Fields (refer Table 11-2). At this stage no well stimulations beyond those identified in Table 11-1 are confirmed. Stimulation requirements for the QCLNG project beyond 2014 will be developed over the next two years. It is expected that in the order of 1,900 wells may be stimulated over the life of the QCLNG project. 180

Stimulation Easting Northing Block Well # Tenure completion date (E_MGA94) (N_MGA94)

Celeste 10 ATP 648 20/11/2011 270893.18 6990093.82

Celeste 11 ATP 648 22/11/2011 270893.18 6988593.26

Myrtle 9 ATP 621 20/04/2012 270893.18 6966408.58

Myrtle 10 ATP 621 30/04/2012 268659.05 6967122.6

Cameron 8 ATP 852 24/05/2012 769685.1 7109076.46

Cameron 10 ATP 852 07/06/2012 769482.54 7108052.6

Kathleen 6 ATP 651 16/04/2013 766550.452 7097888.617

Kathleen 3 ATP 651 21/04/2013 766686.401 7098716.439

Kathleen 2 ATP 651 27/04/2013 765622.056 7099344.191

Kathleen 5 ATP 651 01/05/2013 765315.547 7098418.084

Clunie 7 ATP 648 02/06/2013 288871.896 6977144.231

Clunie 8 ATP 648 10/06/2013 288208.099 6976713.773

Clunie 9 ATP 648 17/06/2013 289544.684 6976881.162

Clunie 10 ATP 648 26/06/2013 288499.545 6977848.576

Table 11-1 – Well stimulations, 2011 to 2013

Location of Completed ! WANDOAN ! Cameron 8, 10 X and Planned Stimulation LocationWells of

! ! ! Cam 6 completedLocation of Candomp plannedleted Kathleen 2, 3, 5, 6 ! ! ! WANDOAN X ! Cameron 8, 10 X andT oPwnl/Caitny ned Stimulation ! Location of Completed Woleebee Creek 109, !! ! stimulation wells 111, 119, 120, 129 ! Main Road ! !! WANDOAN Wells Cameron! 8, 10 X and Planned Stimulation Mamdal 3, 5, 6 ! QGC Field ! ! Cam 6 Wells Kathleen 2, 3, 5, 6 ! ! X QTCowLNn/GC iPtyroject Area ! Woleebee Creek 10!9,! ! ! Cam 6 Town/City Kathleen 2, 3, 5, 6 ! !! ! 111, 119, 120, 129 AMTaPi8n5 R2o, AadTP768 and PL401 !! X Town/City ! ! Main Road Woleebee Creek 109, !! ! Mamdal 3, 5, 6 StimulatiQonG WC eFlilesld 111, 119, 120, 129 Main Road !! ! QCLNG Project Area ! CQoCmLpNleGte Pd rPojreec 2t 0A1re1a Mamdal 3, 5, 6 QGC Field ! QGC Block CAoTmPp8l5e2te, dA T2P01716 8- 2a0n1d3 PL401 Connor 1 ! QCLNG Project Area ! ATP852, ATP768, PL401 StimulaPtiroonp oWsedll s2013 / 2014 ATP852, ATP768 and PL401 ! Completed Pre 2011 SStimulationtimulation WWellsells ! Completed 2011 - 2013 DULACCA ! Completed Pre 2011 X Connor 1 ! MILES Completed pre 2011 ! Proposed 2013 / 2014 X ! Completed 2011 - 2013 Connor 1 ! Completed 2011 - 2013 ! PProposedroposed 22013/2014013 / 2014 XCHINCHILLA DULACCA X ! MILES Andrew 2, 3 ! X JAXNDOWAE XDULACCA XMILES Berwyndale South 11 ! ! CHINCHILLA Arvin 1 ! !! Berwyndale South 21, 22, 28 X ! !!!!! !! Berwyndale South Andrew 2, 3 Berwyndale South 32 CHINCHILLA JANDOWAE 1, 2, 3, 4, 5, 8, 12, 62 X X

Andrew 2, 3 !! JANDOWAE Berwyndale South 11 X ! ! Arvin 1 ! !! Berwyndale South 21, 22, 28 ! !!!!! Berwyndale SBoeruwthy n1d1ale South DATE: 29/10/2013 MAP NO: M_28176_02 Berwyndale South 3!2 ! Arvin 1 ! !! B1,e 2rw, 3yn, d4a, l5e, S8,o 1u2th, 6221, 22, 28 ! CREATED BY: TM REV NO: B !!!!! Berwyndale South Jammat 4 CHECKED BY: PM MAP TYPE: v4Other Berwyndale South 32 ! 1, 2, 3, 4, 5, 8, 12, 62 PLAN REF: ! ! Jordan 9 0 8 16 24 32 Jordan 10 ! Jordan 2 DATE: 29/10/2013 MAP NO: M_28176_02 !! ! ! Jordan 4, 6, 8 Kilometres± Margaret 4, 5, 7 !! CREATED BY: TM REV NO: B ! Jordan 14 DCAHTEEC:KE0D BY2: 98/10/20P1M316 MAP NT2YO4 P: E: M_3281v74O6_th0e2r JamCmealte 4ste 10 ! ! Poppy 14 Celeste 11 !! ! ! CPRLAENAT REEDF B: Y: TKilMometRersEV NO: B !!! ! Jordan 9 Jordan 10 ! !! PM v4Other Celeste 15, 16, 17, 19, J2a0mmat !4 ! !Poppy 15, 191, 192, CMaHp PEroCjecKtioEn: D G DBA Y94: MAP TYPSECA:LE: 1:600,000 (A3) !Celeste 2, J4ord!a!n! 2 ! 201, 211, 212, 213 PLAN REF: !!! ! DATA SOURCE: Roads - NavTeq TARA Jo!rdan 10BarJnoerdy a1n0 J4o, r6d,a 8n 9 ± Margaret 4, 5, 7 !! ! Towns - GA X ! JordJaonr d1a4n 2 ! !! 0 Field8s - DNRM 16 24 32 !!Celeste 10 ! Clunie 7, 8, 9, 10 ! ! !Jordan 4, 6, 8Poppy 14! !! ± Ridgewood 3,! 4!, 5, 6, 10M! ! ! !! Kilometers Margaret 4, 5, 7 Celeste 11!!!! Note: Every effort has been made to ensure this information is spatially accurate. The location of !Jordan! 14Clunie 11, 12 this information should not be relied on as the exact field location. Celeste 15, 16, 17, 19, 20 !!! Map Projection0: GDA 94 8 16 24 SCALE: 312:600,000 (A3) Celeste 10! Poppy 15, 191, 192, "Based on or contains data provided by the State of Queensland (Department of Natural Resources Cele!ste 2, 4 !!! Poppy 14 201, 211, 212, 213 and Mines) 2013. In consideration of the SKtaitleo pmeremtiettrinsg use of this data you acknowledge and Celeste 11 !!! ! ! ! agree that the State gives no warranty in relation to the data (including accuracy, reliability, B!!arney! 10 DATA SOURCE: Roads - NavTeq TARCAeleste 15M, 1yr6tl,e 1 97, 109, 20 !!! A!b!e!rdeen 3, 4, completeness, currency or suitability) and accepts no liability (including without limitation, X ! !!! ! Poppy 15, 191, 192, Maliapb Pilitryo ijne cnetigolnig:e nGceD) Afo r9 a4nyT losws,n dsa m- aGgeA or costs (including consequeSnCtiaAl LdEam: ag1e:)6 r0e0la,t0in0g0 to (A3) !!!Celeste 2, !4 5!,! 6!, 7, 8, 9, 10 any use of the data. Data must nFoti ebeld use -d DforN dRireMct marketing or be used in breach of the privacy laws." Myrtle 1, 2, 3 ! !! ! 201, 211, 212,C 2lu1n3ie 7, 8, 9, 10 ! DATA SOURCE: Roads - NavTeq TARA Ridgewood 3, 4, 5, 6, 1B0aMrney 10 !!!!! X Note: Every effort has been Tmoawden tso e-n GsuAre this information is spatially accurate. The location of Teviot 1 Clunie 11, 12 this informatFioine sldhosu -ld D nNot RbeM relied on as the exact field location. ! !! Clunie 7, 8, 9, 10 ! ! "Based on or contains data provided by the State of Queensland (Department of Natural Resources Ridgewood 3, 4, 5, 6, 10M !!!!! and Mines) 2013. In consideration of the State permitting use of this data you acknowledge and Note: Eavgerreye ethffaotr tth hea Sst abteee gni vmesa dneo twoa errnasnutyre in t hreisla itniofno rtmo athteio dna itsa s(ipnactluiadlilnyg a accccuurraatcey., Trehleia lboilcitay,tion of ! Clunie 11, 12 completethniess isn, fcourrmreantcioyn o rs hsuoiutaldbi lnityo)t abned r eacliceedp otsn n aos l itahbeil ietyx a(icntc lfuiedlidn gl owciathtioount .limitation, Myrtle 9, 10 !!! Aberdeen 3, 4, ! !! "Blaiasbeidlit yo nin o nre cgolingteanincse )d afotar apnroy vloidsesd, dbaym thaeg eS toart ec oosf tQs u(ienecnlusdlainngd c(oDnespeaqrutmenetniat lo df aNmaatugrea)l rReelastoinugrc teos !!! 5, 6, 7, 8, 9, 10 any uasned oMf itnhees d) a2t0a1. 3D. aInta c monussitd neorat tbioen u osfe tdh efo Sr tdaitre cpte mrmairtktientgin ugs oer obfe t huise dda itna byroeua cahc konfo twhele pdrgivea acnyd laws." Myrtle 1, 2, 3 X agree that the State gives no warranty in relation to the data (including accuracy, reliability, Myrtle 9, 10 !!! Aberdeen 3, 4, completeness, currency or suitability) and accepts no liability (including without limitation, ! !!! liability in negligence) for any loss, damage or costs (including consequential damage) relating to T!!e!viot 1 ! 5, 6, 7, 8, 9, 10 any use of the data. Data must not be used for direct marketing or be used in breach of the privacy laws." Myrtle 1, 2, !3

Teviot 1 ! X Figure 11-1 – Location of completed and planned stimulation wells X 181

Stipulation Easting Northing Block Well # completion date (E_MGA94) (N_MGA94)

Woleebee Creek 109 Q1 2014 768,673.997 7,093,098.727

Woleebee Creek 111 Q1 2014 770,076.386 7,092,888.338

Woleebee Creek 119 Q1 2014 767,779.375 7,092,500.000

Woleebee Creek 120 Q1 2014 768,574.000 7,092,558.000

Woleebee Creek 129 Q1 2014 770,044.376 7,092,169.782

Celeste 15 Q1 2014 271,099.913 6,987,893.514

Celeste 16 Q1 2014 271,206.215 6,988,132.737

Celeste 17 Q1 2014 270,967.640 6,988,074.185

Celeste 19 Q1 2014 270,977.130 6,988,880.611

Celeste 20 Q1 2014 271,195.435 6,989,017.663

Poppy 15 2014 278,289.888 6,986,942.918

Poppy 191* 2014 279,157.659 6,986,866.915

Poppy 192* 2014 279,777.100 6,986,790.000

Poppy 201* 2014 278,445.815 6,986,109.190

Poppy 211 2014 277,716.558 6,985,393.856

Poppy 212* 2014 278,418.670 6,985,407.464

Poppy 213* 2014 279,251.300 6,985,284.000

Poppy 14 2014 279,656.867 6,989,081.130

Barney 10 2014 277,639.205 6,983,753.018

Jordan 2 2014 273,044.532 6,999,524.895

Jordan 4 2014 269,690.721 6,995,826.382

Jordan 6 2014 270,225.021 6,996,403.383

Jordan 8 2014 269,227.516 6,996,386.032

Jordan 10 2014 270,393.891 7,001,344.843

Clunie 11 2014 287,236.884 6,976,596.987

Clunie 12 2014 287,497.754 6,976,839.125

Celeste 2 2014 275,759.437 6,989,049.438

Celeste 4 2014 275,287.289 6,987,565.043

Jordan 4 2014 269,839.620 6,993,643.559

Jordan 14 2014 274,896.270 7,001,711.494

Margaret 4 2014 264,321.489 6,994,827.120

Margaret 5 2014 263,682.796 6,994,498.360

Margaret 7 2014 264,777.789 6,994,249.797

* Well locations and numbers are subject to change pending development optimisation activities

Table 11-2 – Planned well stimulations 2014 182

QGC will provide the Australian Government with an annual review of QCLNG well stimulation activities and estimated activities for the year ahead. The annual review will include: • Details of wells stimulated in previous year and proposed for current year; • Location plans; • Update of indicative estimates of stimulations for future years; • Tabulated summary of completed stimulation risk assessments, and submitted Queensland statutory reports • Toxicological and ecotoxicological profiles of any new chemicals proposed to be used; and • Exception reporting.

The annual review will form part of QGC's annual reporting obligations to the Department, which includes publishing of annual reports on QGC's website at the same time it is provided to the Department in October each year.

11.4 STIMULATION FLUID CONSTITUENTS

QGC uses its own produced CSG water , where available, to perform hydraulic stimulations. Well stimulation fluid is 95% water and sand, supplemented with chemicals found in many household products. It may contain gels, nitrified foam and carbon dioxide. Various proppant types are used including sand, resin-coated sand and man- made ceramics depending on the permeability or grain strength needed. For each well stimulation, QGC teams make a selection from the chemicals (including biocides, corrosion inhibitors and other chemicals) listed in Table 11-3. These chemicals are listed on the QGC website at:

http://www.qgc.com.au/environment/environmental-operations/chemicals-used-in-hydraulic-fracturing.aspx

Typically, these chemicals are supplied under a variety of different product names from various suppliers. The scous (e.g. a gel) and which consequentially allows more sand grain per litre of water to be carried into the frac voids. ‘Breaker’ chemicals are required to break the gel connection created in guar gum polymers to assist in returning frac fluid to the surface.

For ideal performance, fracturing fluids possess the following five qualities: • Be sufficiently viscous (thick) to create a fracture of adequate width; • Maximise fluid travel distance to extend fracture length; • Be able to transport required amounts of proppant (e.g. sand) into the fracture; • Require minimal gelling agent to allow for easier degradation or 'breaking'; and • Not lead to contamination of aquifers used or potentially used by others.

Queensland government EA requirements preclude the use of polycyclic aromatic hydrocarbons or products that contain polycyclic aromatic hydrocarbons in stimulation fluids at concentrations above the reporting limit. QGC also prohibits the use of a range of organic chemicals by stimulation contractors such as monoaromatic petroleum hydrocarbons (e.g. benzene), diesel, phenols, ethylene glycol, aromatic solvents and formaldehyde.

The well stimulation fluids (see Table 11-3) for QGC’s 2013 program are representative of the range of fluids that have been used in general to date and are representative of those that are likely to be used in coming years. It should be recognised however that the current programs undertaken by QGC are aimed at assessing fracture fluid effectiveness and consequently fluid mixture chemistry may change in future to improve particular fluid functionalities (e.g. fracturing foams and x-linkers). Significant changes will be noted in the annual report. 183

Service Company Name or Chemical operation Common uses CAS number Handling Name and function

Biocide

Tributyl tetradecyl Biocide used industrial cleaning, oil BE-09 81741-28-8 phosphonium chloride field waters, papermaking

BE-6 Bronopol Eliminates bacteria in water 52-51-7

Tetrakis (hydroxymethyl) Eliminates bacteria in water for Magnacide 575 55566-30-8 phosphonium sulfate farming uses

M275, BPA68915 Magnesium Nitrate Eliminates bacteria in water 10377-60-3

Sodium Hypochlorite, BE-7 Sodium hypochlorite Household bleach, disinfectants 7681-52-9

Disodium octaborate K-38 Fertiliser 12008-41-2 tetrahydrate

Clay control

Tetramethylammonium L064, ClayTreat-3C Salt used for protein purification 75-57-0 chloride

KCl Potassium chloride Fertilisers 7447-40-7

ClayCare, ClayTreat-2C, Choline chloride Agricultural feed additive 67-48-1 Choline chloride

ClayCare, ClayTreat–2C, Choline chloride Agricultural feed additive 67-48-1 Choline chloride

Corrosion inhibitor

Marshmallows, canned hams, Gelatine Gelatine desserts and dairy products, 9000-70-8 pharmaceuticals

Crosslinker

XLW-10A Sodium Tetraborate Detergents, soaps 1303-964

Antiseptic for abrasions, flame 10043-35-3, L010, Boric Acid Boric acid retardant 001333-73-9

Disodium octaborate K-38 Flame Retardant, Wood treatment 12008-41-2 tetrahydrate

Agricultural Plant Food/Fertilizer, 14808-60-7 (link CL-28M Borate Salt Industrial Glass Manufacturing N/A) Additive

Gel

J580, GW-3, GW-4, GW-38, Guar gum, Polysaccharide, 9000-30-0, Food thickening agent WG-36, WG-11 Carbohydrate polymer 68130-15-4

GLFC-5 Guar slurry Thickening agent 9000-30-0

Thickening agents, creams, WG-21, WG-17 Cellulose derivative 9004-62-0 ointments 184

Service Company Name or Chemical operation Common uses CAS number Handling Name and function

Function: Gel breaker

Hemicellulase enzyme GBW-30 Food additives, coffee processing 9012-54-8 carbohydrates

Hemicellulase enzyme GBW-12CD Food additives, coffee processing 9025-56-3 carbohydrates

Silica (with crushed walnut Optiflow HTE Cosmetics, exfoliants 14808-60-7 shells)

GBW-18 Sodium persulfate Hair bleaching, detergents 7775-27-1

Vicon NF Chlorous acid, sodium salt Food Additive 7758-19-2

Hair bleach, household cleaners, Diammonium J218, J479, GBW-5 etching copper, printed circuit 7727-54-0 peroxidisulphate boards

Preservative, Stain Remover, Bleach Gel stabiliser Gel-Sta L Sodium thisosulfate 7772-98-7 and Chlorine Remover

Friction Reducer FR-46 Ammonium sulfate Fertilisers 7783-20-2

Other

Nitrogen Nitrogen Refrigeration, supercooling, inert gas 7727-37-9

Carbon Dioxide Carbon dioxide Dry Ice 124-38-9

Sodium Chloride, Rock Salt Sodium chloride Table salt 7647-14-5

Oxygen Scavenger

Removal of dissolved oxygen in Oxygon Organic acid salt 6381-77-7 fluids, meat processing

Leather tanning, fish farming, GS-1L Sodium thiosulfate 7772-98-7 photography, medicines

pH buffer

M003, Soda Ash Sodium carbonate Neutralise acids, water softening 497-19-8

Manufacturing of paper, textiles, Sodium Hydroxide Sodium hydroxide drinking water, soaps, detergents, 1310-73-2 drain cleaner

BF-3 Sodium Bicarbonate Baking soda 144-55-8

BF-7L Potassium carbonate Additive in soaps, wines, dyes, glass 584-08-7

Carbonic Acid,sodium salt J494 Detergents, soaps 533-96-0 (2:3)

Acetic Acid, BF10L, L401 Acetic acid Vinegar 64-19-7

HCl Hydrochloric acid Swimming pool pH control 7647-01-0

Surfacant

Bathroom Cleaner, Dishwashing Ethanol, Terpene and GasPerm 1100 Detergent, Dish Soap, Multi-surface 64-17-5, 68647-72-3 Terpenoid, Sweet orange-oil Cleaner, Beer

Superflo 2000 Terpene Used as a food additive in Beer 68647-72-3

Table 11-3 – Hydraulic fracturing fluid constituents 185

11.5 STIMULATION FLUID RISK ASSESSMENT AND ECOTOXICITY HAZARD ASSESSMENT

CSG water from the Surat Basin is used for stock and domestic water supply purposes. In a 2012 study by DNRM it was established that representative test freshwater organisms are sensitive to untreated CSG water due primarily to its high salinity. Consequently the aim of the stimulation fluid ecotoxicity hazard assessment is to characterise the incremental hazard of stimulation chemicals and flowback waters to aquatic biota as compared to CSG waters.

The risks to MNES associated with stimulation fluids are considered as part of a wider risk assessment framework. This framework uses the standard industry recognized process which defines Risk as Impact x Probability. The elements of the process are illustrated in Figure 11-2. As part of the Hazard Characterisation process, QGC has initiated a program of ecotoxicity testing to satisfy Condition 53B b (formerly 49f) of referral EPBC 2008/4398 approval. The Condition states that QGC must include as part of their Coal Seam Gas Water Monitoring and Management Plan (WMMP):

“...details of constituent components of any hydraulic fracturing agents and any other reinjected fluid(s), and their toxicity as individual substances and as total effluent toxicity and ecotoxicity, based on methods outlined in the National Water Quality Management Strategy...”

The Ecotoxicity Work Program was submitted to The Department for its endorsement on 31 May 2013, in line with QGC’s Stage 2 WMMP Commitment 39. It was reviewed by ERISS and a discussion was held with all parties on 13th June 2013 when remaining issues were discussed and incorporated in the updated work program.

This work program is part of a collaborative effort with the other CSG Proponents (APLNG and GLNG) to jointly undertake this ecotoxicity work program, where QGC has been nominated as the program operator. An outline of the program is presented in Figure 11-3.

The objective of this project is to define and implement a program that will investigate the ecotoxicity of well stimulation fluids to surface water organisms taking into account the natural background ecotoxicity of CSG water to surface water ecosystems to quantify potential impacts.

It must be recognised that the focus of the program is to make a quantitative assessment of the potential incremental hazard of stimulation chemicals on ecosystems including MNES if such chemicals were released to the environment via controlled or uncontrolled means. Given that there is a negligible to low risk of migration of stimulation chemicals to the external environment (under either controlled or uncontrolled conditions), it is important that the reporting of the ecotoxicity program will be undertaken within a risk-based context.

The other key element of the risk assessment is the Probability of an event occurring which depends on the pathway and likelihood components. As demonstrated in Santos’ extensive probability assessment both pathway occurrences and likelihood are low. Therefore, there is little risk of stimulation fluids entering receiving waters of the Murray-Darling Basin or Dawson River Catchments. The key findings of the risk assessment process are indicated in Figure 11-4.

These aspects will be included and documented in the final stimulation risk assessment.

Please note that in the work program the use of the term ‘total effluent’ which has been used in Condition 53B(b) has been replaced by the word ‘mixture’ or similar. 186

Impact x Probability = Risk

Pathway Hazard Hazard Exposure Characterisation Likelihood Risk Identification Characterisation Assessment (how will contact occur?)

Properties of How much chemical Surface Chemicals exposure? Likelihood Present Guidance values exist? Incremental How much Subsurface consequence exposure? Assumptions to ecology about exposure Hazardous to in the guidance Semi aquatic biota? How much quantitative Assumptions Accidental relevant to local exposure? population

To be completed following ecotoxicity assessment

Figure 11-2 – Direct toxicity assessment in a risk assessment framework

11.6 ECOTOXICITY HAZARD ASSESSMENT WORK PROGRAMS

In line with its commitments, QGC has implemented the following: • Assessment of the toxicity of individual chemicals of concern; • Provision of toxicity and ecotoxicity data, where available, for chemicals in the Stage 1 and Stage 2 WMMPs; and • Preparation of a workplan for direct toxicity testing of stimulations fluids (see Section 11.6).

The work plan is presented in Appendix M.

The direct toxicity testing work plan has been substantially agreed with ERISS and is underway. That program will be complete by December 2013. The results will be incorporated into an assessment of the risk to MNES posed by stimulation fluids, it will incorporate: • The toxicity of individual chemicals of concern; • The potential pathways and likelihood of release and migration; and • Potential receptors.

The DTA program, which consists of a number of tasks is outlined below:

Task 1 – Hydraulic fluid constituents review A review of the ecotoxicity of constituents of hydraulic stimulation fluids used by QGC and its contractors. The review will be extended to look at stimulation fluids and constituents used by the two other CSG proponents. For constituents which are either (i) not well described in terms of ecotoxicology or (ii) are widely used in circumstances that could lead to environmental releases, a more detailed literature review of their ecotoxicology will be carried out. 187

Stimulation fluids and CSG water

Stimulation fluid Stimulation fluid CSG test waters and CSG water B and CSG water CSG flowback waters

2 x NaCl 2 x NaHCO3 2 x Flow back water type water type Stimulation fluids and waters lab water

Stimulation fluid Stimulation fluid A and Lab water B and lab water

Test species

Algae Duckweed Daphnia Shrimp Midge Rainbow fish

Trigger values and species sensitivity distribution for stimulation fluids in the context of CSG waters

Figure 11-3 – Outline of ecotoxicity testing program

Task 2 – Representative area and baselining Direct toxicity assessment of representative CSG water samples will be undertaken to assess the ecotoxicity of in situ groundwater in the Walloon Coal Measures. The testing will be undertaken on fresh water organisms. Other proponents will select samples for testing based on a ‘representativeness’ criterion for their tenements.

Task 3 – Assessment of incremental toxicity from hydraulic stimulation fluid mixtures Representative samples will be tested comprising various volumetric mixes of hydraulic stimulation fluid and: • Typical CSG water used for stimulation activities and sampled at selected representative well-heads; and • Laboratory water to determine the incremental (eco)toxicity over the baseline for freshwater organisms.

An independent review of the fluids used in the testing, has been carried out by a stimulation expert (Appendix M) who concluded that:

“Based on historic information provided by QGC and the author’s knowledge of the local industry, the fracturing fluid formulations designed, mixed and tested for this QGC initiated ecotoxicity testing project are a fair representation of hydraulic fracturing fluids that have been pumped in the past in Queensland CSG and are very likely to be continued to be employed in future CSG wells in Australia”.

Typical frac pond water (which is a mixture of variously sourced CSG waters subject to rainfall dilution and evaporative concentration) will also be tested. Hydraulic stimulation fluids will be tested as a mixture unless a constituent is deployed for which the whole fluid testing has an identified significant incremental toxicity, for which the individual source needs to be identified. Figure 11-3 illustrates the format of the tests. Representative samples of CSG waters, hydraulic stimulation fluid and CSG water mixtures from QGC’s northern, central and southern blocks will be tested. QGC will report the findings of its study in Q4 2013 in line with its Commitment 40. 188

Task 4 – Assessment of a ‘worst case’ An assessment of the potential worst case for CSG and/or hydraulic stimulation fluid (alone or in combination) toxicity will be carried out. This will assist in developing preventative measures during the hydraulic stimulation activities, if required. For the QCLNG project, several MNES have been identified as being relevant to the assessment of Condition 53B(b). In particular potential impacts on MNES listed species, the Fitzroy River Turtle and Murray Cod were considered relevant with a focus on the protection of aquatic ecosystems.

Source Hazard/Pathway Receptor Potential Risk Risk

Workers at Accident/emergency Direct contact Very Low Raw material wellhead conditions

Chemicals, Spillage to surface Accident/emergency transport/storage Ecology Very Low water/groudwater conditions

Direct Contact Workers Not possible

Fraccing fluids prior to injection

Spillage Ecology Not possible

Subsurface Groundwater users, Not significant Very Low migration livestock, irrigation Fraccing fluids post injection Well annulus migration

Accident/emergency Direct Contact Workers Very Low condition Flowback water post injection Frac pond Discharge to surface overtopping water/groundwater Ecology Very Low accident/emergency road tanker spillage condition

Figure 11-4 – Stimulation fluids pathway assessment

Several key knowledge requirements were raised in the ERISS Review of the QGC Stage 2 WMMP, which are considered in this ecotoxicity program (ERISS: Comments on Condition 49f of QGC’s Stage 2 CSG Water Monitoring and Management Plan). These included knowledge requirements to understand the potential risk of well stimulation chemicals to MNES, in particular: 189

• The extent to which well stimulation chemicals contribute to any toxicity observed in the well stimulation fluids; and, • The extent to which well stimulation chemicals increase the toxicity of CSG water.

11.7 PROGRAM STATUS

As at June 2013 the following tasks have been completed or are in progress: • Collection of representative QGC CSG water samples; and • Baseline ecotoxicity testing (in progress), out of 64 separate ecotoxicity tests one remains to be completed (November 2013).

The forward schedule is presented at Figure 11-5.

QGC has already implemented the following commitments: • Assessing toxicity of individual stimulation chemicals of concern; • Provision of toxicity and ecotoxicity data for chemicals in the Stage 1 and Stage 2 WMMPs; and • Ecotoxicity assessments to be carried out in accordance with the 2000 NWQMS Australian and New Zealand Guidelines for Fresh and Marine Water Quality.

The following actions are in progress: • Having an independent review of the QGC stimulation fluids testing program undertaken prior to proceeding; • Submission of a peer reviewed report in December 2013; and • Commitment to ensure representative samples of flow back water are collected immediately after stimulation activities and the date and time of testing is recorded.

2013 Apr May Jun Jul Aug Sep Oct Nov Dec

CSG water collection

CSG water toxocity testing (Test phase 1)

CSG water ecotoxicity (Test phase 1) reporting

Frac fluid viscosity trials/preliminary testing

Mixing of frac fluids for ecotoc testing

Frac fluid testing - with lab and CSG waters

Data Analysis and report preparation

Flowback Water Program

Flowback water collection (all companies)

Flowback water toxicity testing

Report preparation

Final reporting

Figure 11-5 – QGC ecotoxicity program schedule 190

# Department Condition Description Completion date Status

Pre-Dec 2012 Post-Dec 2012

Commitments completed Evergreen Commitments Commitments work in progress Firm deliverables for that month