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AGL Upstream Investments Pty Ltd

Waukivory Pilot Project

Surface Water and Groundwater MonitoringReport to 31 December 201427 February 2015

Document information

Client: AGL Upstream Investments Pty LtdTitle: Waukivory Pilot ProjectSubtitle: Surface Water and Groundwater Monitoring Report to 31 December 2014Document No: 2268523A-WAT-RPT-001 RevADate: 27 February 2015

Rev Date Details

A 12/02/2015 First Draft

B 24/02/2015 Second Draft

C 25/02/2015 Third Draft

D 27/02/2015 Fourth Draft

E 27/02/2015 Final

Author, Reviewer and Approver details

Prepared by: David Whiting, WendyMcLean, Becky Rollins Date: 27/02/2015 Signature:

Reviewed by: Stuart Brown Date: 27/02/2015 Signature:

Approved by: Sean Daykin Date: 27/02/2015 Signature:

Distribution

AGL Upstream Investments Pty Ltd, Parsons Brinckerhoff file, Parsons Brinckerhoff Library

©Parsons Brinckerhoff Australia Pty Limited 2014

Copyright in the drawings, information and data recorded in this document (the information) is the property of ParsonsBrinckerhoff. This document and the information are solely for the use of the authorised recipient and this documentmay not be used, copied or reproduced in whole or part for any purpose other than that for which it was supplied byParsons Brinckerhoff. Parsons Brinckerhoff makes no representation, undertakes no duty and accepts noresponsibility to any third party who may use or rely upon this document or the information.

Document owner

Parsons Brinckerhoff Australia Pty LimitedABN 80 078 004 798Level 27 Ernst & Young Centre680 George Street, Sydney NSW 2000GPO Box 5394Sydney NSW 2001AustraliaTel: +61 2 9272 5100Fax: +61 2 9272 5101Email: [email protected]

Certified to ISO 9001, ISO 14001, AS/NZS 4801A GRI Rating: Sustainability Report 2011

AGL Upstream Investments Pty Ltd Waukivory Pilot ProjectSurface Water and Groundwater Monitoring Report to 31 December 2014

Parsons Brinckerhoff | 2268523A-WAT-RPT-001 RevA i

ContentsPage number

Glossary vi

Abbreviations xii

Units xiv

Executive summary xv

1. Introduction 1

1.1 Gloucester Gas Project 1

1.2 Waukivory Pilot Project 1

1.3 Objectives 2

1.4 Scope of works 2

2. Pilot testing program 7

2.1 Pilot well testing 7

2.2 Waukivory Pilot 7

2.2.1 Schedule 72.2.2 Target fracture stimulation zones 8

3. Site characterisation 9

3.1 Site location 9

3.2 Rainfall 9

3.3 Surface hydrology 11

3.4 Geological setting 11

3.5 Hydrogeological setting 15

4. Monitoring program 17

4.1 Introduction 17

4.2 Monitoring network 17

4.2.1 Groundwater 174.2.2 Surface water 204.2.3 Pilot wells 20

4.3 Water level monitoring 21

4.3.1 Groundwater 214.3.2 Surface water 21

4.4 Water quality monitoring 21


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4.4.1 Water quality sampling frequency 214.4.2 Sampling techniques 254.4.3 Chemical analysis of water 254.4.4 Quality assurance 27

4.5 Key analytes: fracture stimulation additives 27

4.6 Water volumes 29

4.7 Assessment criteria and trigger response 29

5. Water level trends 31

5.1 Groundwater levels 31

5.1.1 Alluvium 315.1.2 Shallow rock 315.1.3 Interburden of deeper coal measures 325.1.4 Deep groundwater 345.1.5 Vertical hydraulic gradients 39

5.2 Surface water levels 39

6. Water quality 42

6.1 Introduction 42

6.2 Groundwater quality 43

6.2.1 Physico-chemical parameters 436.2.2 Major ions 466.2.3 Dissolved metals 476.2.4 Nutrients 506.2.5 Dissolved gases 516.2.6 Dissolved hydrocarbons 52

6.3 Surface water quality 55

6.3.1 Physico-chemical parameters 556.3.2 Major ions 576.3.3 Dissolved metals 586.3.4 Nutrients 616.3.5 Dissolved gases 616.3.6 Dissolved hydrocarbons 626.3.7 Comparison with ANZECC guidelines 62

6.4 Environmental isotopes 63

6.4.1 Stable isotopes 636.4.2 Strontium isotopes (87Sr/86Sr) 656.4.3 Radiocarbon isotopes 676.4.4 Carbon and hydrogen isotopes of methane (δ13C-CH4 and δ2H-CH4) 68

6.5 Gas wells and produced water 71

6.5.1 Fracture stimulation fluid 716.5.2 Flowback and produced water monitoring 72

6.6 Fracture stimulation additives 74

6.6.1 Tetrakis (hydroxymethyl) phosphonium sulphate (THPS) – phosphorus,sulphate and THPS 80

6.6.2 Monoethanolamine borate – boron, nitrogen and monoethanolamine 80


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6.6.3 Sodium hypochlorite – free and residual chlorine 83

7. Conclusions 86

8. Statement of limitations 90

9. References 91

List of tablesPage number

Table 2.1 Fracture stimulation schedule 7Table 2.2 Target fracture stimulation intervals 8Table 3.1 Stratigraphy of the Gloucester Basin 12Table 3.2 Four hydrogeological units – Gloucester Basin 15Table 4.1 Groundwater monitoring network 18Table 4.2 Surface water monitoring network 20Table 4.3 Monitoring schedule 21Table 4.4 Monitoring dates and reasoning for sampling 23Table 4.5 Comprehensive suite of analytes 25Table 4.6 Fracture stimulation additives and breakdown constituents 28Table 5.1 Comparison of WK13 perforated intervals and WKMB05 monitored intervals 36Table 6.1 Groundwater quality parameters discussed in this report 42Table 6.2 Stable isotope results 64Table 6.3 Strontium isotope (87Sr/86Sr) results 65Table 6.4 δ 13C-DIC, radiocarbon and tritium results for the upthrust monitoring bores 67Table 6.5 Dissolved methane concentrations and isotope results 68Table 6.6 Summary of fracture stimulation fluid volumes for each gas well 71Table 6.7 Summary of raw water and fracture stimulation fluid concentrations 71Table 6.8 Flowback volumes recovered up to 31 December 2014 73Table 6.9 Flowback and produced water monitoring 73Table 6.10 Key analytes – time series observations 75Table 6.11 Generalised beneficial use matrix, based on salinity and yield 84Table 6.12 Summary statistics for electrical conductivity during baseline and fracture

stimulation water quality monitoring 85

List of figuresPage number

Figure 1.1 Regional location 4Figure 1.2 Groundwater and surface water monitoring network 5Figure 1.3 Waukivory monitoring network 6Figure 3.1 Long term annual rainfall and cumulative deviation from annual mean (CDFM)

rainfall at Gloucester Post Office BoM station 060015 (BoM 2014) 10Figure 3.2 Monthly rainfall and cumulative deviation from the monthly mean (CDFM) rainfall at

the AGL Gloucester station since installation in July 2011 (AGL, 2014b) 10Figure 3.3 Geological map of the Gloucester Basin 13Figure 3.4 Waukivory interpreted seismic section (from Parsons Brinckerhoff 2014a) (line of

section is shown on Figure 1.3) 14Figure 4.1 Waukivory water quality sampling frequency 22


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Figure 5.1 Groundwater levels and rainfall at the Waukivory monitoring bores 33Figure 5.2 Schematic comparison of WK13 perforated intervals and WKMB05 monitored

intervals 35Figure 5.3 Sensor depth (mbgl) vs sensor pressure (mH20) at WKMB05 37Figure 5.4 Groundwater levels and rainfall at multizone monitoring well WKMB05 38Figure 5.5 Groundwater levels and rainfall at vibrating wire piezometer PL03 39Figure 5.6 Surface water levels and rainfall at the Waukivory stream gauges 41Figure 6.1 Groundwater laboratory EC 44Figure 6.2 Groundwater field pH 45Figure 6.3 Major ion chemistry of groundwater during baseline 46Figure 6.4 Major ion chemistry of groundwater during fracture stimulation and flowback 46Figure 6.5 Dissolved metal concentrations in groundwater 47Figure 6.6 Dissolved iron concentrations in groundwater 48Figure 6.7 Dissolved zinc concentrations in groundwater 49Figure 6.8 Dissolved strontium in groundwater 49Figure 6.9 Boron concentrations in surface water and groundwater 50Figure 6.10 Dissolved methane (CH4) in groundwater 51Figure 6.11 Toluene concentrations in groundwater 53Figure 6.12 Phenol concentrations in groundwater 53Figure 6.13 3-&4-methylphenol concentrations in groundwater 54Figure 6.14 2-methylphenol concentrations in groundwater 54Figure 6.15 Surface water laboratory and logger EC 56Figure 6.16 Surface water field pH 57Figure 6.17 Major ion chemistry of surface water during baseline 57Figure 6.18 Major ion chemistry of surface water during fracture stimulation 58Figure 6.19 Dissolved metal concentrations in surface water 58Figure 6.20 Dissolved iron concentrations in surface water 59Figure 6.21 Dissolved zinc concentrations in surface water 60Figure 6.22 Strontium concentrations in surface water 60Figure 6.23 Boron concentrations in surface water and groundwater 61Figure 6.24 Dissolved methane (CH4) in surface water 62Figure 6.25 Deuterium versus oxygen-18 for groundwater and surface water 64Figure 6.26 Strontium isotope ratios (87Sr/86Sr) for groundwater and surface water 67Figure 6.27 Depth versus 13C-CH4 70Figure 6.28 13C-CH4 versus 2H-CH4 70Figure 6.29 Monoethanolamine concentrations in surface water and groundwater 76Figure 6.30 THPS concentrations in surface water and groundwater (LoR 50 µg/L ±50 µg/L) 77Figure 6.31 Free chlorine in surface water and groundwater 78Figure 6.32 Total residual chloride concentrations in surface water and groundwater 79Figure 6.33 Total nitrogen concentrations in groundwater 82Figure 6.34 Total nitrogen concentrations in surface water 83

List of appendicesAppendix A Waukivory monitoring bore logsAppendix B Parsons Brinckerhoff sampling proceduresAppendix C Laboratory QC reportsAppendix D Summary results of water quality and isotope dataAppendix E Analyte time-series hydrographsAppendix F ALS and Envirolab Services laboratory reportsAppendix G Isotope laboratory reports


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GlossaryAcid Wash A technique to enhance formation permeability through the use of acid to dissolve

sediments that may be blocking fractures and inhibiting permeability.

Alluvium Unconsolidated sediments (clays, sands, gravels and other materials) depositedby flowing water. Deposits can be made by streams on river beds, floodplains, andalluvial fans.

Alluvial aquifer Permeable zones that store and produce groundwater from unconsolidated alluvialsediments. Shallow alluvial aquifers are generally unconfined aquifers.

Aquifer Rock or sediment in a formation, group of formations, or part of a formation that issaturated and sufficiently permeable to transmit economic quantities of water.

Baseline sampling A period of regular water quality and water level measurements that are carriedout over a period long enough to determine the variability in groundwaterconditions.

Biogenic methane Biogenic methane is the principal product of anaerobic and bacterialdecomposition of buried organic material. Biogenic methane can be formed by twoprocesses; acetate fermentation where methanogens use acetate to produce CO2and methane, or CO2 reduction (where methanogens use hydrogen gas to reduceCO2).

Bore A structure drilled below the surface to obtain water from an aquifer or series ofaquifers.

Carbon-13 (13C) A natural, stable isotope of carbon and one of the environmental isotopes. Itmakes up about 1.109% of all naturally occurring carbon on Earth.

Carbon-14 (14C) Or radiocarbon is a radioactive isotope of carbon. Its nucleus contains six (6)protons and eight (8) neutrons. Its presence in organic materials is used inradiocarbon dating. It occurs naturally and has a relative abundance up to one partper trillion (0.0000000001%) of all naturally-occurring carbon on Earth. Carbon-14is one of the most important nuclides in groundwater studies because its half-life of5,730 years covers a critical time scale of ~500 to 50,000 years, which is ideal fordating regional and intermediate flow systems.

Coal A sedimentary rock derived from the compaction and consolidation of vegetationor swamp deposits to form a fossilised carbonaceous rock.

Coal seam A layer of coal within a sedimentary rock sequence.

Coal seam gas(CSG)

Coal seam gas is a form of natural gas (predominantly methane) that is extractedfrom coal seams.

Concentration The amount or mass of a substance present in a given volume or mass of sample,usually expressed as microgram per litre (water sample) or micrograms perkilogram (sediment sample).

Conceptual model A simplified and idealised representation (usually graphical) of the physicalhydrogeologic setting and the hydrogeological understanding of the essential flowprocesses of the system. This includes the identification and description of thegeologic and hydrologic framework, media type, hydraulic properties, sources andsinks, and important aquifer flow and surface water-groundwater interactionprocesses.


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Confining layer Low permeability strata that may be saturated, however will not allow water tomove through it under natural hydraulic gradients.

Datalogger A digital recording instrument that is inserted in monitoring and pumping bores torecord pressure measurements and water level variations.

Detection limit The concentration below which a particular analytical method cannot determine,with a high degree of certainty, a concentration.

Deuterium (2H) Also called heavy hydrogen, a stable isotope of hydrogen with a naturalabundance of one atom in 6,500 of hydrogen. The nucleus of deuterium, called adeuteron, contains one proton and one neutron, where a normal hydrogen nucleushas just one proton.

Dissolved inorganiccarbon (DIC)

The total inorganic carbon (CT or TIC) or dissolved inorganic carbon (DIC) is thesum of inorganic carbon species in a solution. The inorganic carbon speciesinclude carbon dioxide, carbonic acid, bicarbonate anion, and carbonate.

Drawdown A lowering of the water table in an unconfined aquifer or the pressure surface of aconfined aquifer caused by pumping of groundwater from bores and wells.

Electricalconductivity (EC)

A measure of a fluid’s ability to conduct an electrical current and is an estimation ofthe total ions dissolved. It is often used as a measure of water salinity.

Flowback water The return to surface of fracture stimulation fluids before transition to naturalformation water (groundwater), after which water flowing from the well is termedproduced water.

Fracture Breakage in a rock or mineral along a direction or directions that are not cleavageor fissility directions.

Fracture stimulation Fracture stimulation involves pumping a fluid under pressure through theperforated interval into the coal seam to open cracks or fractures, increasing theconnectivity and enabling the flow of water and gas.

Fracture stimulationfluid mixture

The fluid is typically a mixture of sand, water (raw water) and additives.

Fractured rockaquifer

These occur in sedimentary, igneous and metamorphosed rocks which have beensubjected to disturbance, deformation, or weathering, and which allow water tomove through joints, bedding planes, fractures and faults. Although fractured rockaquifers are found over a wide area, they generally contain much less groundwaterthan alluvial and porous sedimentary rock aquifers.

Global MeteoricWater Line (GMWL)

A line that defines the relationship between oxygen-18 (18O) and deuterium (2H) infresh surface waters and precipitation from a number of global reference sites.

Groundwater The water contained in interconnected pores or fractures located below the watertable in the saturated zone.

Groundwater age The amount of time that has elapsed since a particular water molecule of interestwas recharged into the subsurface environment until this molecule reaches aspecific location in the system.

Groundwater level The water level measured in a bore; this may be at or close to the water table inunconfined aquifers, or represent the average piezometric level across thescreened interval in confined aquifers.

Half-life Half-life (t½ is the amount of time required for a quantity to fall to half its valuesmeasured at the beginning of the time period).


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Hydraulicconductivity

The rate at which water of a specified density and kinematic viscosity can movethrough a permeable medium (notionally equivalent to the permeability of anaquifer to fresh water).

Hydraulic fracturing See fracture stimulation.

Hydraulic gradient The change in total hydraulic head with a change in distance in a given direction.

Hydraulic head A specific measurement of water pressure above a datum. It is usually measuredas a water surface elevation, expressed in units of length. In an aquifer, it can becalculated from the depth to water in a monitoring bore. The hydraulic head can beused to determine a hydraulic gradient between two or more points.

Hydrogeology The study of the interrelationships of geologic materials and processes with water,especially groundwater.

Hydrology The study of the occurrence, distribution, and chemistry of all surface waters.

Ion An ion is an atom or molecule where the total number of electrons is not equal tothe total number of protons, giving it a net positive or negative electrical charge.

Isotope One of multiple forms of an element that has a different number of neutrons thanother atoms of that element. Some isotopes are unstable or undergo radioactivedecay, while others are ’stable isotopes’.

Lithology The study of rocks and their depositional or formational environment on a largespecimen or outcrop scale.

Local MeteoricWater Line (LMWL)

A line that defines the local relationship between oxygen-18 (18O) and deuterium(2H) in fresh surface waters and precipitation. In this report the LMWL used is forthe Sydney region.

Major ions Constituents commonly present in concentrations exceeding 10 milligram per litre.Dissolved cations generally are calcium, magnesium, sodium, and potassium; themajor anions are sulphate, chloride, fluoride, nitrate, and those contributing toalkalinity, most generally assumed to be bicarbonate and carbonate.

Methane (CH4) An odourless, colourless, flammable gas, which is the major constituent of naturalgas. It is used as a fuel and is an important source of hydrogen and a wide varietyof organic compounds.

Micro Siemens percentimetre (µS/cm)

A measure of water salinity commonly referred to as EC (see also electricalconductivity). Most commonly measured in the field with calibrated field meters.

Monitoring bore A non-pumping bore, is generally of small diameter that is used to measure theelevation of the water table and/or water quality. Bores generally have a short wellscreen against a single aquifer through which water can enter.

Oxidation-redoxpotential (ORP)

The redox potential is a measure (in volts) of the affinity of a substance forelectrons – its electronegativity – compared with hydrogen (which is set at 0).Substances more strongly electronegative than (i.e. capable of oxidising) hydrogenhave positive redox potentials. Substances less electronegative than (i.e. capableof reducing) hydrogen have negative redox potentials. Also known as reductionpotential.

Oxygen-18 (18O) A natural, stable isotope of oxygen and one of the environmental isotopes. Itmakes up about 0.2% of all naturally-occurring oxygen on Earth.

Percent moderncarbon (pMC)

The activity of 14C is expressed as percent modern carbon (pMC) where 100 pMCcorresponds to 95% of the 14C concentration of NBS oxalic acid standard (close tothe activity of wood grown in 1890).


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Percentile The value below which a given percentage of observations fall. For example, the5th percentile is the value below which five percent of observations are found.

Perforation For pilot wells, perforation is holes punctured in the casing of a pilot well to gainaccess to the gas and water associated with the coal.

Permeable material Material that permits water to move through it at perceptible rates under thehydraulic gradients normally present.

Permian The last period of the Palaeozoic era that finished approximately 252 million yearsbefore present.

PetroleumExploration Licence(PEL)

A Petroleum Exploration Lease (PEL) allows a company to exclusively explore adefined area for petroleum, including undertaking desktop studies, collectingsamples and drilling.

PetroleumProduction Lease(PPL)

A Petroleum Production Lease (PPL) allows a company exclusive rights to extractthe resource within the area defined by the PPL. A PPL is only granted after ademonstration to the NSW Government that the resource is of benefit to the Stateand can be extracted safely and without damage to the environment or heritageareas and infrastructure.

pH Potential of Hydrogen; the logarithm of the reciprocal of hydrogen-ionconcentration in gram atoms per litre; provides a measure on a scale from 0 to 14of the acidity or alkalinity of a solution (where 7 is neutral, greater than 7 is alkalineand less than 7 is acidic).

Piezometricpressure

See hydraulic head.

Produced water Natural groundwater generated from coal seams during flow testing andproduction dewatering.

Pumpcommissioning

The period over which pumps are installed and tested, following fracturestimulation.

Radiogenic A radiogenic nuclide is a nuclide that is produced by a process of radioactivedecay. Radiogenic nuclides (more commonly referred to as radiogenic isotopes)form some of the most important tools in geology. They are used in two principalways:

1. In comparison with the quantity of the radioactive 'parent isotope' in a system,the quantity of the radiogenic 'daughter product' is used as a radiometricdating tool (e.g. uranium-lead geochronology).

2. In comparison with the quantity of a non-radiogenic isotope of the sameelement, the quantity of the radiogenic isotope is used as an isotopic tracer(e.g. 206Pb/204Pb).

Raw water Source water used in the fracture stimulation fluid mixture.

Recharge The process which replenishes groundwater, usually by rainfall infiltrating from theground surface to the water table and by river water reaching the water table orexposed aquifers. The addition of water to an aquifer.

Recharge area A geographic area that directly receives infiltrated water from surface and in whichthere are downward components of hydraulic head in the aquifer. Rechargegenerally moves downward from the water table into the deeper parts of an aquiferthen moves laterally and vertically to recharge other parts of the aquifer or deeperaquifer zones.


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Recovery The difference between the observed water level during the recovery period aftercessation of pumping and the water level measured immediately before pumpingstopped.

Reducing conditions Conditions in which a chemical species gains electrons and is present in reducedform.

Salinity The concentration of dissolved salts in water, usually expressed in EC units(µS/cm) or milligrams of total dissolved solids per litre (mg/L TDS).

Salinity classification Fresh water quality – water with a salinity <800 µS/cm.Marginal water quality – water that is more saline than freshwater and generallywaters between 800 and 1,600 µS/cm.Brackish quality – water that is more saline than freshwater and generally watersbetween 1,600 and 4,800 µS/cm.Slightly saline quality – water that is more saline than brackish water and generallywaters with a salinity between 4,800 and 10,000 µS/cm.Moderately saline quality – water that is more saline than slightly saline water andgenerally waters between 10,000 and 20,000 µS/cm.Saline quality – water that is almost as saline as seawater and generally waterswith a salinity greater than 20,000 µS/cm.Seawater quality – water that is generally around 55,000 µS/cm.

Sandstone Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rockgrains (predominantly quartz).

Screen A type of bore lining or casing of special construction, with apertures designed topermit the flow of water into a bore while preventing the entry of aquifer or filterpack material.

Sedimentary rockaquifer

These occur in consolidated sediments such as porous sandstones andconglomerates, in which water is stored in the intergranular pores, and limestone,in which water is stored in solution cavities and joints. These aquifers are generallylocated in sedimentary basins that are continuous over large areas and may betens or hundreds of metres thick. In terms of quantity, they contain the largestvolumes of groundwater.

Siltstone A fine-grained rock of sedimentary origin composed mainly of silt-sized particles(0.004 to 0.06 mm).

Stable isotopes Stable isotopes are atoms of the same element that have different masses due todifferences in the number of neutrons they contain. Stable isotopes are not subjectto radioactive decay, meaning they do not breakdown over time.

Stratigraphy The depositional order of sedimentary rocks in layers.

Strontium isotopes 87Sr is radiogenic; it is produced by decay from the radioactive alkali metal 87Rb,which has a half-life of 4.88 × 1010 years. Thus, there are two sources of 87Sr inany material: that formed during primordial nucleo-synthesis along with 84Sr, 86Srand 88Sr, as well as that formed by radioactive decay of 87Rb. The ratio 87Sr/86Sr isthe parameter typically reported in geologic investigations; ratios in minerals androcks have values ranging from about 0.7 to greater than 4.0. Because strontiumhas an electron configuration similar to that of calcium, it readily substitutes for Cain minerals.


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Surface water-groundwaterinteraction

This occurs in two ways: (1) streams gain water from groundwater through thestreambed when the elevation of the water table adjacent to the streambed isgreater than the water level in the stream; and (2) streams lose water togroundwater through streambeds when the elevation of the water table is lowerthan the water level in the stream.

Thermogenicmethane

Thermogenic methane forms when organic matter present in a sedimentarygeological formation is subjected to heat and pressure created by deep burial ofsediments (coalification). The stress of this geological “maturation” process causesthe methane molecule (CH4) to break off from larger organic compounds.

Total dissolvedsolids (TDS)

A measure of the salinity of water, usually expressed in milligrams per litre (mg/L).

Trace element An element found in only minor amounts (concentrations less than 10 milligramper litre) in water or sediment; includes heavy metals arsenic, cadmium,chromium, copper, lead, mercury, nickel, and zinc.

Water bearing zone Geological strata that are saturated with groundwater, however not of sufficientpermeability to be called an aquifer.

Water quality Term used to describe the chemical, physical, and biological characteristics ofwater, usually in respect to its suitability for a particular purpose.

Water quality data Chemical, biological, and physical measurements or observations of thecharacteristics of surface and ground waters, atmospheric deposition, potablewater, treated effluents, and waste water and of the immediate environment inwhich the water exists.

Water table The top of an unconfined aquifer. It is at atmospheric pressure and indicates thelevel below which soil and rock are saturated with water.

Well Pertaining to a gas exploration well or gas production well.


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AbbreviationsAGL AGL Upstream Investments Pty Ltd

ANZECC Australian and New Zealand Environment Conservation Council

ALS Australian Laboratory Services

BTEX Benzene, toluene, ethyl-benzene and xylenes

BoM Bureau of Meteorology

BP Before Present

CDFM Cumulative deviation from mean

CSG Coal seam gas

DIC Dissolved inorganic carbon

DO Dissolved oxygen

EC Electrical conductivity

EPA Environment Protection Authority

EPL Environment Protection Licence

GDE Groundwater Dependent Ecosystems

GFDA Gas Field Development Area

GGP Gloucester Gas Project

GMWL Global Meteoric Water Line

GRL Gloucester Resources Limited

H2O Water

LMWL Local Meteoric Water Line

LoR Limit of reporting

LTA Long term average

MGA Map grid of Australia

NEPM National Environment Protection Measures

NOW NSW Office of Water

OCSG Office of Coal Seam Gas

ORP Oxidation-reduction potential

PEL Petroleum Exploration Licence

PPL Petroleum Production Lease

PQL Practical quantification limit

QA/QC Quality assurance/quality control

SGMP Surface water and groundwater management plan


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THPS Tetrakis (hydroxymethyl) phosphonium sulphate

TRH Total recoverable hydrocarbons

TDS Total dissolved solids

TOC Total organic carbon


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UnitsºC degrees Celsius

µg/L micrograms per litre

µS/cm microSiemens per centimetre

% percent

‰ per mil

kL kilolitres

km kilometres

km2 square kilometres

kPa kilopascal

L/s litres per second

m metres

m/d metres per day

m3/s cubic metres per second

mAHD metres Australian Height Datum

mbgl metres below ground level

mg/L milligram per litre

mm millimetres

mmol/L millimol per litre

pCM percent modern carbon

TU tritium unit

V volt

yrs BP years before present


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Executive summaryThis report presents the initial groundwater and surface water monitoring results and their interpretation forthe Waukivory Pilot Project (exploration) activities within the Stage 1 area of the Gloucester Gas Project(GGP) from 1 September to 31 December 2014. It includes baseline data collected from March to October2014 and data collected during fracture stimulation and the commencement of the flowback phase from lateOctober to December 2014. The report provides results of monitoring data from the water monitoringnetwork, as well as raw (source) water, fracture stimulation fluid, and flowback water quality and volumesrecovered following fracture stimulation of pilot wells WK11, WK12, WK13, and WK14.

The reporting of this monitoring data is a requirement of Petroleum Exploration Licence PEL 285 andEnvironment Protection Licence (EPL) 20358. The monitoring program and subsequent reporting meets therequirements of the Surface and Groundwater Management Plan (SGMP) (AGL 2014a) and relevantsections of EPL 20358.

The scope of work for this report included:

· Interpretation of water level and water quality trends.

· Assessment as to whether trends are naturally occurring or potentially attributed to Project activities.

· Assessment of key analytes associated with fracture stimulation additives defined in AGL’s SGMP

· Comparison of monitoring data against default ANZECC (2000) guideline values where available forprotection of freshwater aquatic ecosystems to assess if elevated concentrations exist in the naturalenvironment.

The current groundwater monitoring network at the Waukivory site consists of seven groundwater monitoringbores, one multizone monitoring well (six zones monitored), and one vibrating wire piezometer location (twozones monitored). There are three surface water monitoring sites at Waukivory located on the Avon Riverand Waukivory Creek.

Baseline sampling was undertaken to characterise the pre-Project groundwater and surface water conditionsat the Waukivory site. The baseline sampling comprised four sampling events in March, June, Septemberand October 2014. The monitoring frequency was increased during the fracture stimulation and flowbackphases in accordance with EPL 20358.

Groundwater level monitoring was conducted using pressure transducer loggers in the bores and verifiedwith regular manual measurements. The analytical suite for water quality included physico-chemicalparameters (electrical conductivity, total dissolved solids, pH, temperature, oxygen-reduction potential,dissolved oxygen and total suspended solids), major ions, dissolved metals and minor trace elements,nutrients, hydrocarbons, dissolved gases, fracture stimulation additives, and environmental and radioisotopes. The criteria used for assessment of monitoring data follows the SGMP.

Key results and conclusions from this program to 31 December 2014 are as follows:

Groundwater levels

Groundwater levels in the alluvial and shallow rock monitoring bores show distinctive responses to highrainfall events in 2014. This is followed by a gradual decline (recession) period which may continue forseveral months until the next rainfall event occurs.


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Groundwater levels in monitoring bore WKMB03 screened in the deep interburden/fault zone do not show aresponse to individual rainfall events. The groundwater level shows a general decreasing trend during thebaseline period of March to October 2014 (which is a broad regional response) due to below average rainfallconditions over the period.

The deep multizone piezometer WKMB05, located 164 m from WK13, shows an increase in piezometrichead with depth as would be expected in the centre of a closed groundwater basin. The deepest two sensorsrecord elevated piezometric pressures consistent with influence from the deepest fracture stimulation zonesin WK13. These observations are consistent with preliminary numerical modelling and also indicate that thepressure influence from fracture stimulation is restricted in the vertical direction (confined).

Groundwater levels in alluvial monitoring bores (GR-P3), shallow rock bores (WKMB01, WKMB02,GW080487 and WKMB06B) and the deep interburden/fault zone bore (WKMB03) show no responseattributable to the fracture stimulation of the pilot wells and the commencement of pumping during initialflowback in December 2014. The nested bore WKMB06A/B installed within the alluvium and shallow rock inNovember 2014 also showed no response from pilot well activities during period of monitoring from 19November through to 31 December 2014.

Groundwater quality

Baseline sampling of groundwater and surface water streams at the Waukivory site occurred in March, June,September and October 2014. Further intense water sampling occurred during the pilot well fracturestimulation and initial flowback periods in November and December 2014. Key conclusions are:

n Monitoring of baseline conditions indicates groundwater within the alluvium is fresh to brackish andgroundwater in the shallow rock is marginally to slightly saline.

n Major ions, dissolved metals and nutrients showed no distinctive trends between the baseline periodand the fracture stimulation/flowback period which may be attributed to pilot well activities. Identifiedtrends in concentrations are attributed to natural variability over time. The concentration of phosphorusin groundwater remained consistent with background levels during fracture stimulation and initialflowback with the exception of WKMB06A and WKMB06B. Concentrations of phosphorus in WKMB06Aand WKMB06B will be monitored in future scheduled periodic monitoring. This monitoring will assess ifthis is a continuous trend or potentially related to the recent construction of the bores and related aquiferdisturbance.

n Methane concentrations varied considerably between bores, with lowest concentrations in the alluvium.The fractured rock bores showed a rising trend extending from the baseline period through the fracturestimulation/flowback period. This is attributed to degassing of naturally occurring methane after purgingduring groundwater sampling events.

n The BTEX compound toluene was detected in shallow rock groundwater (ranging from 6 to 72 µg/L).There was no detection of benzene, ethyl benzene or xylenes within shallow groundwater systems.

n Phenol and phenolic compounds have also been detected in the groundwater within the shallow rockand are considered to be natural occurring within coal measures.

n No distinctive trends in water quality were identified at groundwater monitoring sites that were attributedto pilot well activities.

Surface water levels

n Water levels at stream gauge sites WKSW01 (Avon River upstream), WKSW02 (Waukivory Creekupstream) and WKSW03 (Avon River downstream) reduced between September 2014 and early - midDecember 2014 due to the very low rainfall over this time period. Water levels are close to the zerogauge height at each site, and represent ponded water.


Parsons Brinckerhoff | 2268523A-WAT-RPT-001 RevA xvii

n Available water level data at the stream gauge sites do not show a response attributable to fracturestimulation or the initial flowback phase in late October – December 2014.

Surface water quality

n The streams are characterised as fresh and of neutral to slightly alkaline pH.

n EC, pH, major ions, dissolved metals, nutrients and dissolved gases showed no anomalous trendsduring the baseline and flow back periods. Identified trends in concentrations were attributed to naturalvariability over time, particularly the period of low rainfall and evaporative concentration over the lastmonths of 2014. Baseline boron concentrations in surface water range from <0.05 – 0.12 mg/L. Duringthe fracture stimulation period, surface water boron concentrations peak at WKSW01 on 19 November2014 (0.32 mg/L). This peak is not attributed to fracture stimulation activities as WKSW01 is locatedupstream of the Project on the Avon River. Concentrations of boron in surface water were belowlaboratory LoR during the commencement of the flowback phase.

n Total phosphorus is elevated above ANZECC guidelines for 80% and 95% protection of freshwateraquatic ecosystems. These elevated levels are attributed to agricultural activity in the area.

n Dissolved hydrocarbons including BTEX, PAH, Phenols and TPH were not detected in surface watersamples during baseline, fracture stimulation and initial flowback phases.

n No distinctive trends in water quality were identified at surface water monitoring sites that wereattributed to pilot well activities.

Fracture Stimulation fluid

n The fracture stimulation fluid contained no detectable BTEX, phenols and PAH.

Flowback Water

n The initial flowback water from the pilot wells is more saline (high total dissolved solids) and has greaterdissolved metal concentrations than the fracture stimulation fluid that was injected into the wells. Thisincrease in concentrations is due to mixing of fracture stimulation fluid with more saline deepgroundwater in the coal seams.

n Flowback water from WK12 and WK13 contained BTEX and other hydrocarbon compounds. TotalBTEX was detected at the following concentrations in samples from pilot wells: WK12 (47 µg/L on 29December 2014) and WK13 (70 µg/L on 16 December 2014 and 555 µg/L on 29 December 2014), andin the flowback tank (AST) (35 µg/L on 29 December 2014). Following receipt and review of theseresults, AGL voluntarily suspended the Project. BTEX compounds were not detected in the raw watersupply, nor in the fracture stimulation fluid. In addition, review of sampling and laboratory protocolspreclude contamination of samples with BTEX during sampling and analysis. The occurrence of BTEXcompounds in the flowback water is the subject of ongoing investigation by relevant regulators; howeveris considered to be naturally occurring and derived from the deeper coal seams.

Fracture stimulation additive concentrations during and post fracture stimulation

THPS

n TPHS was not detected in baseline groundwater or surface water monitoring.

n THPS was detected at three isolated locations during the fracture stimulation period. The detectionswere marginally above the LoR (50 μg/L), and within the margin of error of the LoR (50 μg/L ±50 μg/L).

n THPS was not detected in groundwater or surface water monitoring during the initial flowback phase.

Monoethanolamine Borate


xviii 2268523A-WAT-RPT-001 RevA | Parsons Brinckerhoff

n MEA was detected in baseline groundwater and surface water samples at concentrations ranging fromless than the LoR (1 μg/L) to 4 μg/L.

n MEA was detected in regional background groundwater and surface water samples at up to 10 km fromthe Project at concentrations ranging from less than the LoR to 19 μg/L. There is a negligible likelihoodthat MEA detected in these samples is associated with the fracture stimulation fluid given their distancesfrom the Project.

n DEA was detected in baseline and regional groundwater and surface water samples and is readilybiodegraded in the environment to MEA.

n Detections of MEA were recorded in four groundwater samples collected on 12/13 November 2014.MEA was not detected in the groundwater samples collected at the monitoring event on 17 Novemberimmediately after the 12/13 November 2014 (also during the fracture stimulation period) with theexception of WKMB01 which recorded an MEA concentration of 3 µg/L.

n All samples collected during the fracture stimulation period on 20 November 2014 from groundwaterclose to and distant from the pilot wells, and surface water both downstream and upstream of the wellsdetected MEA with concentrations ranging between 2 and 60 µg/L. MEA was not detected in thesamples collected at the monitoring event on 24 November immediately after the 20 November 2014(also during the fracture stimulation period).

n A review of sampling and laboratory protocols did not identify contamination of samples.

n The two highest concentrations of MEA in water samples were detected in the shallow rock atGW080487 (61 μg/L) on 13 November 2014, and at WKMB02 (60 µg/L) on 20 November 2014. Theconcentrations of all MEA detections (including the 60 μg/L (WKMB02) and 61 μg/L (GW080487)) arewithin the same order of magnitude of the highest regional background detections to date (19 μg/L).

n Where MEA was detected in surface water and groundwater, THPS concentrations were less than theLoR (50 μg/L ±50 μg/L) with the exception of WKMB03 on 12 November 2014 when the THPSconcentration was 57 μg/L which is considered within the margin of error of the LoR (i.e. likely to be afalse positive result).

n MEA concentrations were below laboratory LoR in surface water and groundwater samples collectedduring the sampling event undertaken during the initial flowback phase.

n AGL has provided information to the relevant regulators on MEA detections.

n The source of MEA is currently unknown. The detection of MEA at measurable concentrations inbaseline samples and the regional background samples indicate that MEA is likely to originate from asource not related to the fracture stimulation fluid.

Isotope Studies of Water Origin and Age

n Deuterium versus Oxygen 18 results indicate the alluvial and shallow rock water is meteoric (originatingfrom atmosphere-rainfall) in origin as it lies on the Global Meteroric Water Line.

n Tritium analyses and radiocarbon dating indicate groundwater within the alluvium and surface water aremodern (< 50 years). Groundwater in the shallow rock is older, at between 2,300 to 7,100 years old.

n Carbon 13 and deuterium isotope results of dissolved methane of both surface and groundwaterindicate it is of thermogenic origin with exception of shallow rock bore WKMB06B in which the methaneis likely biogenic in origin. The results were comparable with methane isotope data for deep gas wellsand results for groundwater monitoring bores sampled during previous studies in Gloucester Basin.

Water Beneficial Use Conditions

There was no change in the water beneficial use category for alluvial and shallow bedrock water resourcesduring and after the pilot well fracture stimulation activities.


Parsons Brinckerhoff | 2268523A-WAT-RPT-001 RevA xix

Actions to correct identified adverse trends

Analysis of monitoring results has not identified adverse trends that require corrective action.Notwithstanding, the following actions are being undertaken:

n Due to the baseline and regional detections of MEA, investigations into alternative fracture stimulationtriggers in surface water and groundwater samples have commenced and will be provided to therelevant regulators for consideration in advance of future pilot programs.

n The occurrence of BTEX compounds in the flowback water is the subject of ongoing investigation byrelevant regulators; however is considered to be naturally occurring and derived from the deeper coalseams. Corrective actions including enhanced monitoring have been proposed by AGL and arecurrently under review as part of the investigation by regulators. The suspension will remain in placeuntil this review is complete.


Parsons Brinckerhoff | 2268523A-WAT-RPT-001 RevA 1

1. IntroductionThis report presents groundwater and surface water level and quality data collected at Waukivory during2014. The report combines data collected during the baseline monitoring period from March to October 2014,and during the Waukivory Pilot Project (the Project) from late October to 31 December 2014, which includedthe fracture stimulation and commencement of the flowback phase. The Waukivory Project is an explorationactivity as distinct from broader activities associated with the development phase of the Gloucester Gasproject.

1.1 Gloucester Gas ProjectAGL Upstream Investments Pty Ltd (AGL) is proposing to build the Gloucester Gas Project (GGP) whichcomprises several stages of development facilitating the extraction of coal seam gas (CSG) from theGloucester Basin. Concept Plan and Project Approval (Part 3A Approval) for the Stage 1 Gas FieldDevelopment Area (GFDA) was granted on 22 February 2011 under Part 3A of the Environmental Planningand Assessment Act (1979) (EP&A Act). In addition the project received approval under the EnvironmentProtection and Biodiversity Conservation Act (1999) (EPBC Act) (EPBC Approval) on 11 February 2013.

AGL holds Petroleum Exploration Licence (PEL) 285, under the Petroleum (Onshore) Act 1991, covering thewhole of the Gloucester Basin, approximately 100 km north of Newcastle, NSW. PEL 285 expired on15 April 2012 and was renewed on 6 August 2014. The Stage 1 GFDA in relation to the PEL 285 boundary isshown in Figure 1.1. The Stage 1 GFDA with AGL owned properties and the water monitoring network isshown in Figure 1.2.

The GGP will involve the depressurisation of deep groundwater and the extraction of gas from multiple coalseams within the Gloucester Coal Measures. Target coal seam depths will vary from site to site with anexpected range of 200 to 1,000 metres below ground level (mbgl). The Stage 1 GFDA includes theconstruction, operation, and decommissioning of 110 CSG wells and associated infrastructure, including gasand water gathering lines.

A dedicated water monitoring network is in place which has enabled the collection of baseline water leveland water quality data for the different groundwater and surface water systems within the Gloucester Basin.There are now more than 50 dedicated water monitoring locations and more than four years of baselinemonitoring (water levels and water quality) across the Gloucester Basin.

1.2 Waukivory Pilot ProjectAGL received approval for the Waukivory Pilot Project from the NSW Office of Coal Seam Gas (OCSG) on 6August 2014. The approval was included with the renewal of PEL 285 and permitted AGL to fracturestimulate and flow test four existing pilot gas wells located within the Stage 1 GFDA of the GGP (AGL2014a). These four pilot wells were installed between 2 October and 24 November 2012. Fracturestimulation commenced on 27 October 2014, with the final fracture stimulation on 26 November 2014. Theflowback phase (process of commissioning pumps and returning fracture stimulation fluids back to thesurface) commenced on 16 December 2014.

The pilot wells (Waukivory 11 (WK11), Waukivory 12 (WK12), Waukivory 13 (WK13), and Waukivory 14(WK14)) are located in the northern part of the GFDA on properties leased from Gloucester ResourcesLimited (GRL) (Figure 1.3). The wells have been perforated and fracture stimulated within target coal seamsranging from approximately 370 to 960 mbgl.


2 2268523A-WAT-RPT-001 RevA | Parsons Brinckerhoff

A surface water and groundwater management plan (SGMP) was prepared by AGL (AGL 2014a) for theProject and approved by the OCSG and NSW Office of Water (NOW) prior to the commencement of theProject. Accompanying the renewal of PEL 285, the NSW Environment Protection Authority issuedEnvironment Protection Licence (EPL) 20358 for the Gloucester Coal Seam Gas Project on 6 August 2014.The SGMP provides a framework which describes how surface water and groundwater in the localWaukivory area will be monitored and assessed during fracture stimulation and flow testing (which includesdewatering) of the deep coal seams. EPL 20358 requires the monitoring of the concentration of analytes andpollutants at prescribed monitoring locations at given frequencies using appropriate sampling methods.

NOW and EPA requirements for groundwater and surface water monitoring of CSG activities, applicable tothis report, include:

n Establishment of baseline conditions.n Collection of periodic water level, water quality and volumetric datan Reporting of data and trends

This report complies with the reporting requirements outlined in Section 6.8 of the SGMP and addresses thegeneral requirements of the EPL 20358, Condition R4.3. There are some differences in the monitoringrequirements (locations, frequencies and analytes) identified in the SGMP compared to those stipulated inthe EPL. This technical report focuses on the requirements of the SGMP.

1.3 ObjectivesThe objectives of this quarterly reporting of water monitoring data for the Project are to meet thecommitments stated in the approved SGMP (Section 6.8, pages 51 – 52), as follows:

“The quarterly reports will include:

n Analysis and interpretation of monitoring results including trends; andn Details of any triggers requiring specific management and actions to be undertaken.

The first report will cover the period from 1 September to 31 December 2014 and will include baseline dataobtained prior to the commencement of fracture stimulation activities for the Waukivory Pilot Project.”

Monitoring results include data obtained from groundwater and surface water monitoring points, and pilotwell discharge (flowback and produced water). For the purpose of presenting all baseline data collected forthe Project, data from March 2014 is also presented in this report.

1.4 Scope of worksIn preparing this quarterly report the following was conducted:

n Description of the monitoring program undertaken in 2014, which included a description of themonitoring network, frequency of monitoring events, suite of analytes measured, sampling techniques,assessment criteria and quality assurance.

n Presentation of water levels and water quality data collected during the baseline period and the periodof pilot well activities from the start of the Project in March to 31 December 2014. Pilot well activitiesinclude fracture stimulation of wells and the start of flowback.

n Presentation of environmental isotope data to characterise the origin, age, and processes that haveaffected groundwater in the stratigraphic sequence.

n Presentation of water quality results for raw (source) water, fracture stimulation fluid (raw water plusadditives), and flowback water from each pilot well during the Project.



n Presentation of key analyte concentrations for monitoring fracture stimulation additives and comparisonwith background concentrations and fracture stimulation fluid.

n Identification of trends associated with natural variations or pilot well activities and comparison ofsurface waters to ANZECC guideline criteria.

n Assessment of any changes to beneficial use of waters during baseline and pilot well activities as atrigger response for the Project.

n Identification of exceedance of triggers which include negative trends from pilot well activities andrecommendations for management actions to be taken.



Figure 1.1 Regional location



Figure 1.2 Groundwater and surface water monitoring network



Figure 1.3 Waukivory monitoring network



2. Pilot testing program2.1 Pilot well testingFracture stimulation and pilot testing are exploration activities that identify potential gas resources by testingthe composition, flow rate, and volume of gas in target coal seams. Fracture stimulation and pilot testing alsoassess water production volumes (as the wells are depressurised to allow gas flow) and assess potentialconnectivity between shallow aquifers and the water bearing zones of the deep coal seams.

The following phases of testing are referred to in this report:

n Baseline sampling was undertaken to characterise the pre-Project groundwater and surface waterconditions at the Waukivory site. The baseline sampling comprised four sampling events in March,June, September and October 2014.

n Fracture stimulation involves pumping a fluid under pressure through a zone of perforated steel wellcasing into the coal seam to open cracks or fractures, increasing the hydraulic conductivity and enablingthe flow of water and gas. The fluid is typically a mixture of sand, water and additives.

n Flowback water is the return to surface (by pumping) of fracture stimulation fluids before transition tonatural formation water (groundwater), after which, water flowing from the well is termed producedwater. Flowback water includes water and fluids extracted during the short period of pumpcommissioning.

n Produced water is formation water which is co-produced with gas, and follows the removal of thefracture stimulation fluid (flowback). Pumping groundwater from a coal seam reduces the pressure andallows the gas and 'produced' groundwater to flow into the well and up to the surface. The flow rate ofproduced water typically decreases over time.

2.2 Waukivory Pilot2.2.1 Schedule

The fracture stimulation of the four pilot wells commenced on 27 October 2014 and finished on26 November 2014. Over the five week program, a total of 19 zones were fracture stimulated from depths of371 to 964 m. Table 2.1 shows the dates over which the fracture stimulation took place at each pilot well,and when flowback commenced.

Table 2.1 Fracture stimulation schedule

Pilot well Fracture stimulationstart date

Fracture stimulationfinish date

Number of fracturestimulation zones

Flowbackcommencement

WK13 27/10/14 05/11/14 9 16/12/14

WK12 zones 1 and 2 08/11/14 12/11/14 4 29/12/14

WK12 zones 3 and 4 19/11/14 20/11/14

WK14 14/11/14 17/11/14 2 (plus 2 acid washzones)

Yet to commence asof 31/12/14

WK11 21/11/14 26/11/14 4 Yet to commence asof 31/12/14



On 12 November 2014 an apparent “tight spot” was encountered in the casing wellbore at WK12. Out ofcaution, it was decided to “rig down” the fracture stimulation equipment and move to WK14 whilst the causeof the tight spot could be investigated prior to further perforating or fracture stimulation at WK12. The tightspot was investigated and found to be an error in the wireline equipment, not an actual tight spot in thecasing wellbore. The wireline equipment was repaired and the wellbore was checked again, confirming notight spot. Once fracture stimulation was completed at WK14 on 17 November 2014, the equipment movedback to WK12 to complete the remaining target intervals. Fracture stimulation at WK12 was completed on20 November 2014.

2.2.2 Target fracture stimulation zones

A summary of the target fracture stimulation zones within each pilot well is provided in Table 2.2.

Table 2.2 Target fracture stimulation intervals

Zone Coal seam Perforation interval(mbgl)

Seam thickness (m)

WK11

1 Avon 928.7 – 964.25 9.36

2 Glenview 860.5 – 879.2 2.18

3 Bowens Road and Fairbairns Lane 806.6 – 838.0 2.46

4 Fairbairns Lane 709.1 – 741.9 2.06

WK12

1 Fairbairns Lane 590.4 – 597.0 1.33

2 Roseville (lower) 485.7 – 504.2 3.24

3 Roseville (upper) 406.0 – 424.1 2.93

4 Cloverdale 371.3 – 385.0 2.42

WK13

1 Triple 934.2 – 946.3 0.91

2 Avon 878.7 – 911.4 10.05

3 Glenview 812.5 – 826.5 2.35

4 Glenview Not perforated or fracture stimulated

5 Fairbairns Lane (lower) 694.1 – 738.3 2.75

6 Fairbairns Lane (upper) 612.2 – 628.8 5.93

7 Roseville (lower) 540.2 – 575.1 2.05

8 Roseville (upper) 514.5 – 523.3 2.79

9 Cloverdale 451.4 – 474.0 2.23

10 Bindaboo 404.5 – 408.4 0.75

WK14

1 Avon 774.5 – 805.8 7.5(a)

2 Fairbairns Lane (lower) 532.5 – 542.0 4.23

3(b) Fairbairns Lane (upper) 473.8 – 490.8 3.81

4(b) Roseville 453.3 – 459.7 2.05(a) Estimated.(b) WK14 zones 3 and 4 are acid wash intervals. Acid wash of zones 3 and 4 were conducted simultaneously.



3. Site characterisation3.1 Site locationThe Waukivory Pilot Project site is located approximately 6 km south of Gloucester, NSW, at 176 FairbairnsLane, Forbesdale. The site is adjacent to the flood plain of the Avon River and is characterised by paddocksused for low intensity cattle grazing. The Avon River flows in a northerly direction through the Project site.The confluence of the Avon River and its eastern tributary, Waukivory Creek, is located toward the centre ofthe site (Figure 1.3).

3.2 RainfallAGL has operated a weather station on the Tiedman property just south of the Project site since July 2011.The closest Bureau of Meteorology (BoM) weather station to the Waukivory site, at Gloucester Post Office(60015), has been operational since 1888. Locations of the weather stations are shown in Figure 1.2.

Long term average annual rainfall (1888 to 2014) at Gloucester Post Office is 981 mm. Rainfall is seasonal,with the highest mean monthly rainfall occurring in the summer months between January and March.

The long-term, annual cumulative deviation from mean (CDFM) rainfall for Gloucester Post Office is plottedin Figure 3.1. The long-term cumulative rainfall residual plots are formulated by subtracting the averageannual rainfall for the recorded period from the actual annual rainfall and then accumulating these residualsover the assessment period. Periods of below average rainfall are represented as downward trending slopeswhile periods of above average rainfall are represented as upward trending slopes.

The cumulative deviation plot for Gloucester Post Office (Figure 3.1) shows that over the last 60 years, short(2-3 year) drought periods have occurred about every 10 to 15 years. However there have been no long-termdeviations from mean conditions, such as the prolonged drought periods that characterised the first half oflast century.

Rainfall data for the period January 2011 to December 2014 are presented in Figure 3.2. The AGL weatherstation commenced monitoring in June 2011; data prior to that was obtained from Gloucester Post Office.For most of the period from March 2014 to December 2014, rainfall was below the monthly average, asindicated by the downward trend of the cumulative deviation plot, with only August 2014 and December 2014recording higher than average rainfall. Total annual rainfall in 2014 was 720 mm which is significantly belowthe long term average for Gloucester.



Figure 3.1 Long term annual rainfall and cumulative deviation from annual mean (CDFM) rainfall atGloucester Post Office BoM station 060015 (BoM 2014)

Figure 3.2 Monthly rainfall and cumulative deviation from the monthly mean (CDFM) rainfall at the AGLGloucester station since installation in July 2011 (AGL, 2014b)



3.3 Surface hydrologyThe Gloucester Basin is a narrow, north-south trending, elongated basin approximately 40 km long and10 km wide, extending from Gloucester in the north to Stroud in the south. The Gloucester Basin is locatedhigh in the Manning River and Karuah River coastal catchments. The area occupied by the sedimentaryrocks of the Basin (about 217 km2) is small in comparison to the size of these catchments.

There is a surface water divide between the Wards River catchment (part of the Karuah River catchment)and the Avon River catchment (part of the Manning River catchment). In the northern Avon River catchment,surface water flow is generally to the north. In the southern Wards River catchment, surface water flow isgenerally to the south.

The Avon River includes the tributaries of Dog Trap Creek and Waukivory Creek within the Stage 1 GFDA(Figure 1.2). The Gloucester River joins the Avon River at the north of the Gloucester Basin. Wards Riverflows to the south, and is outside of the Stage 1 GFDA (Figure 1.2).

3.4 Geological settingThe Gloucester Basin comprises a thick succession of Permian sedimentary rocks representing deposition inboth terrestrial and marine environments during a complex period of subsidence, uplift and relative sea levelchange (marine transgression and regression).

The Basin is a synclinal intermontane structure formed in part of the New England Fold Belt between a majorPermian plate margin and the Sydney-Gunnedah Basin (Lennox 2009). The north–south trending synclinalnature of the Gloucester Basin resulted from the collision between the East Australian and Pacific Plates.

Following a period of extension during the Early Permian, the Gloucester Basin has undergone periods ofnormal and reverse faulting, with large scale tilting associated with late stage compressional movementstowards the end of the Permian (Hughes 1984). Reverse faults dominate present day structure. Acomparison with the contemporary horizontal stress field map (Hillis et al 1998) indicates the Basin is likely tobe under compression in an east-west orientation.

The stratigraphy dips steeply (up to 90°) on the flanks of the Basin, dipping towards the north-south trendingsynclinal basin axis and flattening toward the centre of the Basin. Early Permian and Carboniferous hardresistive volcanics form the ridgelines of the Basin: the Mograni Range to the east; and the Gloucester andBarrington Tops to the west.

Overlying the Permian stratigraphy is a thin sequence of surficial Quaternary sedimentary deposits andregolith. The Quaternary sediments are non-uniform in thickness, and comprise unconsolidated alluvialsediments (sand, gravel, silt and clay) along the drainage channels and colluvial deposits across the rest ofthe plain sourced from the surrounding outcropping Permian deposits.

The Gloucester Basin is divided into three major Permian stratigraphic units each representing a distinctdepositional setting: the Gloucester Coal Measures, the Dewrang Group, and the basal Alum MountainVolcanics. The generalised stratigraphy of the Basin is summarised in Table 3.1. A geological map is shownin Figure 3.3. The development in the Stage 1 GFDA is targeting the intermediate and deep coal seams inthe Gloucester Coal Measures generally below depths of 200 m to around 1000 m.

The fault zones identified at the Project site are mostly reverse faults where older rock strata are thrust overyounger strata. Figure 3.4 shows the trace of the major faults identified on a seismic section through theWaukivory pilot area.



Table 3.1 Stratigraphy of the Gloucester Basin

Period Group Sub-group Formation Approx. thickness (m) Coal seam Depositionalenvironment

Tectonic events

Upp

erPe

rmia

n

Glo

uces

terC

oalM

easu

res

Craven Crowthers Road Conglomerate 350 Marine regression, pro-gradation of alluvialfans

Uplift to west ofGloucester Basin

Leloma 585 Linden

JD

Bindaboo

Deards

Jilleon 175 Cloverdale

Roseville

Tereel/Fairbairns

Wards River Conglomerate Variable

Wenham 23.9 Bowens Road

Bowens Road Lower

Speldon Formation Marine transgressionbut also someprogradation of alluvialfans in the west relatedto uplift

Extension (normal faultdevelopment) andregional subsidence.Uplift to west of Basin

Avon Dog Trap Creek 126 Glenview

Waukivory Creek 326 Avon

Triple

Rombo

Glen Road

Valley View

Parkers Road

Dew

rang Mammy Johnsons 300 Mammy Johnsons Marine transgression,

regression and furthermarine transgression

Extension (normal faultdevelopment) andregional subsidenceWeismantel 20 Weismantel

Duralie Road 250

Low

erPe

rmia

n Alum Mountain Volcanics Clareval Arc-related rift Rift?

Basal

Modified from AECOM (2009) and SRK (2005).



Figure 3.3 Geological map of the Gloucester Basin



Figure 3.4 Waukivory interpreted seismic section (from Parsons Brinckerhoff 2014a) (line of section is shown on Figure 1.3)



3.5 Hydrogeological settingFour broad hydrogeological units have been identified within the Gloucester Basin (Table 3.2). Thepermeability and groundwater flow characteristics of rocks within the Gloucester Basin are controlled byseveral factors including lithology, depth, and the degree of fracturing and faulting. In this sensehydrogeological units and flow systems do not always correspond with defined geological boundaries.

Table 3.2 Four hydrogeological units – Gloucester Basin

Unit Aquifer type Formation name General lithology Hydraulic characteristics

Alluvial deposits Semi-confined,clay capped,porous, granular

Quaternary alluvium Clay/mixed gravels Heterogeneous, highlyvariable permeabilityassociated with varyinglithology

Shallow Rock(<150 m)

Semi-confined,fractured rock

Upper Permian CoalMeasures, AlumMountain Volcanics

Interbeddedsandstone/siltstonewith bedding planefractures

Heterogeneous, high and lowpermeability domainsassociated with fault zonesand fracturing

Interburden ofdeep coalmeasures

Confined,fractured rock,aquitard

Upper Permian CoalMeasures

Interbeddedinduratedsandstone/siltstoneand claystone

Low permeability associatedwith sparse fractures,permeability decreases withdepth

Deep coalSeams

Confined,fractured rock,water bearingzones

Upper Permian CoalMeasures

Coal/shale Low permeability associatedwith cleating and fractures incoal seams, permeabilitydecreases with depth

The four hydrogeological units are summarised as follows:

1. Alluvial deposits adjacent to major creeks and rivers comprising unconsolidated sand, gravel, andclay. The deposits are typically 12 to 15 m thick. These systems are heterogeneous but generallypermeable with rapid recharge, through-flow, and discharge associated with interactions with streams,and to a lesser extent with the underlying less permeable shallow rock. Hydraulic conductivitymeasurements range from 0.3 to 300 metres per day (m/d), averaging around 10 m/d.

2. Shallow rock comprising variably weathered and fractured Permian rocks extending to approximately150 m below the surface, across all sub-cropping Permian units. The shallow rock zone isheterogeneous with relatively impermeable domains separated by more permeable domains, but on thewhole it is more permeable than the deeper coal measures. The domains of higher permeability are dueto a higher density of fracturing associated with an irregular weathering profile and the near-surfaceexpression of faulting. Aquifer zones observed during drilling occur within 75 m of the surface.Groundwater flow within this zone is more strongly controlled by weathering and fracturing than theattitude of geological strata. Hydraulic conductivity of the shallow rock ranges from 10 m/d to 1x10-6 m/dat a depth of 150 m, but is typically in the order of 10-3 to 10-4 m/d.

3. Deep coal measures interburden. Sandstone and siltstone units that form the interburden to coalseams are indurated and typically of very low permeability, forming aquitards and confining layers. Thepermeability of the interburden decreases with depth such that, at the maximum depth of CSGproduction, it is likely to be in the order of 10-5 to 10-7 m/d, or less.

4. Deep coal seams. Coal seams tend to be slightly more permeable than interburden and commonlyform weak water bearing zones at depth. Permeability and storage are provided by small fractures andcleats in the coal. As with interburden, drill-stem tests clearly show that the permeability of coal seamsgenerally decreases with depth. At the maximum depth of CSG production, the permeability of coalseams is very low (10-4 to 10-6 m/d), but may be an order of magnitude higher than the interburden.



The Alum Mountain Volcanics underlie the Permian Coal Measures, and form the impermeable base of theGloucester Basin. The Alum Mountain Volcanics outcrop in the eastern and western boundaries of the Basin,forming the elevated topography of the Gloucester and Barrington Tops to the west, and the Mograni Rangeto the east.



4. Monitoring program4.1 IntroductionThe following section provides an overview of the monitoring program for the baseline period, fracturestimulation, and initial flow testing of the pilot wells. The monitoring program covers the following phases:

n Baseline sampling: Baseline sampling was undertaken to characterise the pre-Project groundwater andsurface water conditions at the Waukivory site. The baseline sampling comprised four sampling eventsin March, June, September, and October 2014.

n Fracture stimulation: The fracture stimulation took place from 27 October 2014 to 26 November 2014and the associated monitoring commitments were undertaken during November and December 2014.

n Flowback water: The initial flowback phase commenced with the installation of pumps in WK12 andWK13 in December 2014. There is therefore limited data collected for this phase during the quarterlyreport period to 31 December 2014.

n Produced water: The produced water phase and associated sampling had not commenced by31 December 2014. The transition from flowback to produced water will be marked by an increase insalinity (measured as electrical conductivity (EC)) to 5,000 µS/cm and a total return to surface offlowback water equal to the volume of fluids injected during fracture stimulation.

4.2 Monitoring networkAGL’s groundwater and surface water monitoring network consists of more than 50 dedicated watermonitoring locations across the Gloucester Basin, as shown in Figure 1.2. There are more than four years ofbaseline monitoring data (water levels and water quality), as reported in the 2014 Groundwater and SurfaceWater Monitoring Status report (Parsons Brinckerhoff 2014b).

4.2.1 Groundwater

The groundwater monitoring network at the Project site (Figure 1.3) consists of:

n Five AGL groundwater monitoring bores (WKMB01, WKMB02, WKMB03, WKMB06A, and WKMB06B)n One AGL multizone monitoring well (WKMB05: six zones monitored)n One AGL vibrating wire piezometer (PL03: two zones monitored)n One GRL groundwater monitoring bore (GR-P3)n One private groundwater monitoring bore (GW080487); andn One private excavation (GW05490)

Details of the groundwater monitoring network are provided in Table 4.1. Full bore logs for the AGLmonitoring bores are provided in Appendix A and Parsons Brinckerhoff (2014d).



Table 4.1 Groundwater monitoring network

Monitoringlocation

EPAID

Total depth(mbgl)

Monitored interval(mbgl)

Lithology Formation Hydro-geologicalunit

Date installed Samplingmethod(e)

Waukivory groundwater monitoring

WKMB01 10 54.0 47.0 – 53.0 Sandstone Leloma Formation(upthrust)

Shallow rock February2012

Micro-purge™

WKMB02 11 61.0 51.0 – 60.0 Sandstone/ siltstone Leloma Formation(upthrust)

Shallow rock June 2012 Micro-purge™

WKMB03 12 210.0 200.0 – 209.0 Sandstone Leloma Formation Interburden (faultzone)

June 2012 Micro-purge™

WKMB04(a) n/a 360.0 335.0 – 347.0 Coal and sandstone Jilleon Formation –Roseville Coal Seam

Coal January 2012 n/a

PL03(b) 14 966.3 Sensor 2: 496 Coal Wenham Formation –Bowens Road Coal Seam

Coal September2013

n/a

Sensor 3: 463 Pebble conglomerate Wards Riverconglomerate

Interburden

WKMB05(c) 85 1,100.0 Sensor 1: 340.0 – 343.0 Siltstone/ sandstone Leloma Formation Interburden(aquitard)

November2014

n/a

Sensor 2: 426.0 – 429.0 Coal Jilleon Formation –Cloverdale Coal Seam

Coal seam

Sensor 3: 584.0 - 587.0 Siltstone/ sandstone Jilleon Formation Interburden(aquitard)

Sensor 4: 595.4 – 598.4 Coal Jilleon Formation –Fairbairns Coal Seam

Coal seam

Sensor 5: 698.5 – 701.5 Siltstone/ sandstone Jilleon Formation Interburden(aquitard)

Sensor 6: 711.0 – 714.0 Siltstone/ sandstone Jilleon Formation Interburden (faultzone)

WKMB06A n/a 13.4 6.4 – 12.4 Mixed gravels Alluvium Alluvium November2014

Submersiblepump



Monitoringlocation

EPAID

Total depth(mbgl)

Monitored interval(mbgl)

Lithology Formation Hydro-geologicalunit

Date installed Samplingmethod(e)

Waukivory groundwater monitoring

WKMB06B n/a 63.0 52.0 – 61.0 Siltstone/ sandstone Leloma Formation Shallow rock (faultzone)

November2014

Micro-purge™

GR-P3 90 11.0 5.0 – 9.0 Mixed gravels Alluvium Alluvium March 2011 Submersiblepump

GW080487 91 60.0 48.0 – 60.0 Shale Leloma Shallow rock n/a Submersiblepump

GW054940(d) n/a 4.0 Unknown Clay, sand Alluvium Alluvium n/a Telescopicsampler

(a) WKMB04 was plugged and abandoned in January 2014.(b) PL03 is a vibrating wire piezometer. Piezometric level is measured at each sensor.(c) WKMB05 is a multizone monitoring well. Each horizon is installed with a pressure transducer to measure the piezometric level.(d) Excavation – Removed from EPL 20358 in October 2014 and replaced with GRL groundwater monitoring bore GR-P3. The excavation (GW054940) was sampled during the baseline sampling round in

March 2014.(e) Further details provided in Section 4.4.2.



WKMB05 is a multizone groundwater monitoring installation situated 164 m east of WK13. The bore wasdrilled to a total depth of 1,100 m and was initially installed with a geophone array to collect data during thefracture stimulation of WK13 to provide an understanding of the propagation of the fracture stimulationeffects.

Following the fracture stimulation of WK13, the geophone array was removed from WKMB05, six intervalsperforated, and an array of packers installed to isolate six horizons within the monitoring bore. At eachhorizon a pressure transducer was installed to measure the piezometric level. The monitored horizons areshown in Table 4.1. Further details on the construction of WKMB05 are provided in Appendix A.

4.2.2 Surface water

The surface water monitoring network at the Project site consists of three AGL stream gauge locations(Figure 1.3). Details of these stream gauges are provided in Table 4.2.

Table 4.2 Surface water monitoring network

Stream gauge EPA ID Easting (MGA, m) Northing(MGA, m)

Location Stream

Waukivory surface water monitoring

WKSW01 9 402002 6452208 Waukivory Avon River (upstream)

WKSW02 8 402772 6452099 Waukivory Waukivory Creek (upstream)

WKSW03 7 402488 6453088 Waukivory Avon River (downstream)

MGA – Map Grid of Australia.

4.2.3 Pilot wells

Raw (source) water was pumped (under licence approval from the NOW) from a farm dam on AGL’sPontilands property (Figure 1.3) to a 1.5 ML above ground storage tank (AST) installed adjacent to WK13.The raw water was mixed with the fracture stimulation additives and sand to make up the fracture stimulationfluid. The raw water comprised 93.6 to 95.4% of the total volume of the fracture stimulation fluid.

Raw (source) water and fracture stimulation fluid (raw water plus additives and sand) were sampled duringthe fracture stimulation of each of the four pilot wells (WK11, WK12, WK13, and WK14). The raw water usedfor each fracture stimulation fluid mix (for each well) was sampled directly from the AST immediately prior toor during the fracture stimulation.

The fracture stimulation fluid was sampled by AGL personnel on the well site immediately prior to fracturestimulation. Following fracture stimulation the fluid sample was collected by Parsons Brinckerhoff personnelfor analysis.

At the completion of the fracture stimulation, pumps were installed in each well to enable flowback. Waterlevels and water quality will be monitored during the flowback and produced water stages. No watersampling was possible during the baseline phase or prior to the fracture stimulation program as the wellswere not perforated and open to the target coal seams. The locations of the four pilot wells are shown inFigure 1.3, and details of the fracture stimulation intervals are provided in Section 2.

Flowback (and subsequent produced water) samples are taken from a sample tap at the well heads ofWK11, WK12, WK13, and WK14. The sample tap is situated downstream of the separator adjacent to thesalinity meter.

Flowback water is pumped to a second AST (also referred to as the Flowback (FB) tank) for storage andtesting prior to disposal.



4.3 Water level monitoring4.3.1 Groundwater

Pressure transducers equipped with a datalogger, recording at six hourly intervals have been installed in thefollowing monitoring bores:

n WKMB01 – monitoring commenced February 2012n WKMB02 and WKMB03 – monitoring commenced June 2012n WKMB05, WKMB06A and WKMB06B – monitoring commenced November 2014n GR-P3 – monitoring commenced March 2011.

A real-time telemetry system is installed at the WKMB monitoring bores to assist timely data collection andassessment of groundwater levels during the Waukivory pilot testing. To calibrate the level recorded by thedataloggers, manual groundwater level measurements are recorded prior to logger downloads.

A barometric datalogger is installed above the water table at WKMB02 to record changes in atmosphericpressure. Data from this logger are used to correct for the effects of changing barometric pressure ongroundwater levels.

Piezometric pressure is recorded every six hours at each of the six sensors in the multizone monitoring wellWKMB05, and at the two virbrating wire piezometers in PL03.

Manual groundwater level measurements are recorded for private bore GW080487 at each periodic visit.

4.3.2 Surface water

The three Waukivory stream gauges were installed in September 2014. Real-time telemetry dataloggers areinstalled to monitor water levels and salinity every 15 minutes. Water levels are verified by manual gaugeboard readings recorded every three months and during sampling events. Electrical conductivitymeasurements, which provide an indication of salinity, are checked every three months using a hand-heldcalibrated water quality meter.

4.4 Water quality monitoring4.4.1 Water quality sampling frequency

The water quality monitoring conditions as stipulated in EPL 20358 are provided in Table 4.3. The frequencyof groundwater and surface water quality sampling undertaken during the Project is presented in Figure 4.1and the exact dates and reason for the sampling is shown in Table 4.4. This includes baseline samplingbetween March and October 2014 (four baseline events), sampling during the fracture stimulation program inNovember 2014, and flowback sampling in December 2014.

Table 4.3 Monitoring schedule

Timeframe Raw(source)water

Fracturestimulationfluid (raw waterplus additives)

Surfacewater

Shallowground-water

Flowbackwater

Producedwater

During fracture stimulation(each pilot well)

ü ü

Within 24 hours of thecompletion of the fracture

ü ü



Timeframe Raw(source)water

Fracturestimulationfluid (raw waterplus additives)

Surfacewater

Shallowground-water

Flowbackwater

Producedwater

stimulation of each pilot well

1 week after the fracturestimulation of each pilot well

ü

2 weeks after completion of thefracture stimulation program

ü

4 weeks after completion of thefracture stimulation program

ü

Fortnightly fromcommencement of flowback

ü

Every 2 months from thetransition to produced water

ü

Figure 4.1 Waukivory water quality sampling frequency



Table 4.4 Monitoring dates and reasoning for sampling

Monitoring point

EPA ID 10 11 12 na na 90 91 9 8 7 Reason for sampling

AGL Location WKMB01 WKMB02 WKMB03 WKMB06A WKMB06B GR-P3 GW080487 WKSW01 WKSW02 WKSW03

Sam

plin

gda

te

11 March 1412 March 1413 March 14

x xx

xx

x xx

2014 baseline #1(pre-Waukivory Pilot)

26 June 1427 June 14

x x xx x x x

2014 baseline #2(pre-Waukivory Pilot)

30 Sept 141 Oct 14

x x x xx

x x x 2014 baseline #3(pre-Waukivory Pilot)

21 Oct 1422 Oct 14

x x x xx x

x x 2014 baseline #4(pre-Waukivory Pilot)

6 Nov 14 x x x x x x x x within 24 hours of thecompletion of thefracture stimulation ofWK13

12 Nov 1413 Nov 14

x x x xx

x x x within 24 hours of thecompletion of thefracture stimulation ofzone 2 WK12(a), oneweek after fracturestimulation of WK13for surface watersamples

17 Nov 1418 Nov 14

x x x x xx

xx

within 24 hours of thecompletion of thefracture stimulation ofWK14

18 Nov 1419 Nov 14

xx x x x

first sampling eventsfollowing installation ofthe new bores, oneweek after fracturestimulation of zone 2WK12 for surfacewater samples



Monitoring point

EPA ID 10 11 12 na na 90 91 9 8 7 Reason for sampling

AGL Location WKMB01 WKMB02 WKMB03 WKMB06A WKMB06B GR-P3 GW080487 WKSW01 WKSW02 WKSW03

20 Nov 14 x x x x x x x x within 24 hours of thecompletion of thefracture stimulation ofWK12

24 Nov 14 x x x one week afterfracture stimulation ofWK14 for surfacewater samples

26 Nov 1427 Nov 14

x x x x xx x x

within 24 hours of thecompletion of thefracture stimulation ofWK11, one week afterfracture stimulation ofWK12 for surfacewater samples

3 Dec 14 x x x one week afterfracture stimulation ofWK13 for surfacewater samples

9 Dec 1410 Dec 14 x

x x xx x

x two weeks after thecompletion of thefracture stimulation ofWK11

22 Dec 1423 Dec 14

x x xx x x

x four weeks after thecompletion of thefracture stimulation ofWK11

(a) Additional sampling event – not required under Special Frequency 3 (EPL 20358)



4.4.2 Sampling techniques

A range of methods were used to obtain groundwater quality samples from the monitoring bores. The mostappropriate method for each bore was selected based on the depth of the bore, the depth to groundwater,and the permeability of the screened formation. Higher yielding monitoring bores were purged and sampledusing a submersible pump. Lower yielding bores were sampled using a low flow pump. Details of thesampling technique used at each monitoring location are provided in Table 4.1.

Submersible pumps were used to purge a minimum of three well volumes (where possible) in high yieldingbores (WKMB06A, GR-P3, and GW080487) prior to sampling to allow a representative groundwater sampleto be collected. Water quality parameters were monitored during the purging to ensure that a representativegroundwater sample was collected.

For lower yielding bores and deeper bores with high purge volumes (WKMB01, WKMB02, WKMB03 andWKMB06B), a dedicated micro-purge™ low flow sampling system was deployed. The micro-purge™ systemallows groundwater to be drawn into the pump intake directly from the screened portion of the aquifer,eliminating the need to purge large volumes of groundwater from these bores. Water quality parameterswere monitored during the micro-purge™ pumping to ensure that a representative groundwater sample wascollected.

A telescopic sampler was used to collect grab samples from the surface water sites. A new bottle is used foreach sampling round and rinsed three times prior to taking the sample. The telescopic sampler is cleanedbetween sampling rounds.

The water quality of each sample was measured in the field using a calibrated hand-held (YSITM) waterquality meter. The following physico-chemical parameters were measured:

n Electrical conductivity – µS/cmn Temperature – °Cn Dissolved oxygen (DO) – % saturation and mg/Ln Oxidation-reduction potential (ORP) – mVn pH – pH unitsn Total dissolved solids (TDS) – mg/L.

Field measurements of free and total residual chlorine were taken using a Hach Pocket Colorimeter.

4.4.3 Chemical analysis of water

Water quality samples were collected in new sample bottles provided by the laboratory, with the appropriatepreservation specific to each analyte. Samples undergoing dissolved metal analysis were filtered through0.45 µm filters in the field prior to collection in plastic sample bottles with nitric acid preservative. Sampleswere analysed for the comprehensive suite of analytes listed in Table 4.5. The comprehensive suite includesall analytes prescribed for the relevant monitoring points in EPL 20358, and those listed in the approvedSGMP.

Table 4.5 Comprehensive suite of analytes

Category Suite of analytes

Field parameters Electrical Conductivity (EC)Total Dissolved Solids (TDS)TemperatureFree and total residual chlorinea

pHRedox potential (ORP)Dissolved oxygen

General parameters (lab) ECTDS (measured)

pHTotal suspended solids



Category Suite of analytes

Major ions CalciumMagnesiumSodiumPotassium

ChlorideCarbonateBicarbonateSulphateFluoride

Dissolved metals and minor/trace elements

AluminiumAntimonyArsenicBariumBerylliumBoronBromineCadmiumChromiumCobaltCopperIron

LeadManganeseMercuryMolybdenumNickelSeleniumStrontiumTinUraniumVanadiumZinc

Other analytes Total organic carbon (TOC)SilicaFree and total residual chlorineb

Monoethanolamine (MEA)c

Tetrakis (hydroxymethyl) phosphoniumsulphate (THPS)e

Nutrientsd NitrateNitriteTotal nitrogen

AmmoniaTotal Kjeldahl NitrogenReactive and total phosphorus

Dissolved gasesd Methane

Hydrocarbons Phenolic compoundsPolycyclic aromatic hydrocarbons (PAH)Total petroleum hydrocarbons (TPH)

Benzene, toluene, ethyl-benzene andxylenes (BTEX)Volatile organic compounds (VOC’s)

Isotopesf Oxygen-18 (18O)Deuterium (2H)Strontium 87/86 (87Sr/86Sr)Tritium (3H)

Carbon-13 dissolved inorganic carbon(13CDIC)Carbon-13 methane (13C-CH4) anddeuterium methane (2H-CH4)Radiocarbon (14C)

(a) Only analysed for surface water sampled in March 2014.(b) Only free chlorine data available for March 2014.(c) Not analysed in March and June 2014 events.(d) Not analysed in the March 2014 sampling event for the private monitoring locations (GW080487 and GW054940).(e) Not analysed in March, June and September 2014 events.(f) Only analysed in March and June 2014 sampling rounds and at WKMB06A and WKMB06B in November 2014.

Samples were sent to the following laboratories under appropriate chain-of-custody protocols:

n Australian Laboratory Service (ALS) Environmental Pty Ltd, Smithfield, Sydney (NATA accreditedlaboratory) – chemistry analysis.

n GNS Stable Isotope Laboratory, Lower Hutt, New Zealand – oxygen-18 and deuterium analysis.n Australian National University (ANU) Research School of Earth Sciences, Canberra – strontium 87/76

analysis.n GNS Tritium and Water Dating Laboratory Lower Hutt, New Zealand – tritium analysis.n UC Davis Stable Isotope Facility, Davis, California, USA – carbon-13 (13CDIC) and methane isotope

analysis (13C-CH4 and 2H-CH4).n Rafter Radiocarbon Laboratory, Lower Hutt, New Zealand – carbon-14 (14C) analysis.n Envirolab Services, Sydney NSW (NATA accredited laboratory) – THPS analysis.



4.4.4 Quality assurance

4.4.4.1 Field QA/QC

All sampling was undertaken in accordance with Parsons Brinckerhoff’s sampling procedures (Appendix B)and the Australia//New Zealand standards for water quality sampling (AS/NZS 5667). The following QA/QCprocedures were applied:

n Dedicated sampling equipment (such as micro-purge™ low flow sampling pumps) and disposable(single use) equipment specific to each sample location:

4 dedicated micro-purge™ pumps were used for lower yielding bores and deeper bores with highpurge volumes for the Waukivory groundwater monitoring network, allowing for less groundwaterdisturbance and minimising loss of volatiles and disturbance of redox conditions

4 samples for metals were field filtered using single use filters and syringes4 surface water samples were collected directly with sample bottles where safe access can be

gained.

n Unstable parameters were analysed in the field, i.e. physical parameters, including pH and free chlorine.n The hand-held water quality meter was calibrated each day for EC and pH.n Two to three well volumes were purged prior to sampling, following stabilisation (±10% for EC and

±0.05 pH units) of key field parameters; note the micro-purge™ low flow sampling pump was designedto reduce the volume of purging required.

n Nitrile gloves were worn while collecting water samples.n Samples were collected in appropriate bottles with appropriate preservation solutions, as specified by

the NATA accredited laboratories.n All bottles for volatile analysis were filled as far as practicable to avoid any head space and loss of

volatiles.n All sample bottles were labelled with the sample ID, date, time and samplers initials.n Samples were placed in eskies containing ice immediately upon collection.n Where sample storage was required overnight, samples were kept chilled and secure.n A chain-of-custody form was completed for each batch of samples, and eskies securely sealed prior to

delivery to the laboratory.n Samples were delivered to the laboratories within the specified holding times, with the exception of pH

and free chlorine, which were also analysed in the field.

4.4.4.2 Laboratory QA/QC

The laboratories conduct their own internal QA/QC program to assess the accuracy and precision of theanalytical procedures. These programs include analysis of laboratory sample duplicates, spike samples,certified reference standards, surrogate standards/spikes and laboratory blanks. Laboratory QC reports areprovided in Appendix C.

4.5 Key analytes: fracture stimulation additivesEPL 20358 specifies three compounds that may be present in fracture stimulation additives that are to beincluded in the analytical suite for all sites:

n Tetrakis (hydroxymethyl) phosphonium sulphate (THPS)n Monoethanolamine boraten Sodium hypochlorite.

Although choline chloride was originally included in the list of fracture stimulation additives and referenced inthe approved SGMP, the EPA removed it from the EPL in November 2014 as AGL did not include cholinechloride as an additive in the fracture stimulation fluid for the Project.



Sodium hypochlorite was also not used as a fracture stimulation additive by AGL, however as discussedbelow, the breakdown constituents of sodium hypochlorite (free and total residual chlorine) were included inthe analytical suite.

In the absence of validated metholodologies for the analysis of the fracture stimulation additives THPS,monoethanolamine borate, and sodium hypochlorite in the approved SGMP, a number of elemental(breakdown) constituents were identified by AGL through consultation with analytical laboratories and theEPA (AGL, 2014c) as potential indicators of the presence of the fracture stimulation fluid in groundwater andsurface water bodies when the individual compounds (listed above) cannot be identified at lowconcentrations in waters. The breakdown constituents were listed as:

n THPS – phosphorus and sulphaten Monoethanolamine borate – boron and nitrogenn Sodium hypochlorite – free and total residual chlorine.

AGL has worked with the EPA since early 2014 to develop the monitoring program for fracture stimulationadditives to be used for the fracture stimulation of the four Waukivory pilot wells. During this time, therefinements which have been made to the fracture stimulation additive analysis required by the EPA underthe EPL have included:

n Water samples from sampling events (from 20 October 2014 onwards) were preserved pendingapproval by the EPA of validated analytical methods for the detection of monoethanolamine borate andTHPS.

n The EPA approved the validated methodology for the analysis of monoethanolamine borate (asmonoethanolamine (MEA)) on 1 December 2014 with a laboratory limit of reporting at 1 µg/L.

n The EPA approved the validated methodology for THPS analysis on 19 December 2014 with alaboratory limit of reporting (LoR) (also referred to as the practical quantitation limit (PQL)) at 50 µg/Lwith a level of uncertainty of ± 50 µg/L (Envirolab 2015).

n Analyses for MEA commenced in October 2014, utilising the method ultimately approved by the EPA on1 December 2014.

n Analyses of THPS commenced in December 2014, following EPA approval of the final validatedmethodology.

With the EPA approval of the analysis methods, the key analytes that may be associated with fracturestimulation additives tracked during the Project are:

n monoethanolamine borate (as MEA)n THPSn free and total residual chlorine (as breakdown constituents of sodium hypochlorite).

The concentration of fracture stimulation additives and breakdown constituents are discussed in detail inSection 6.6 with respect to baseline environmental conditions, hydrogeological conceptual model, andfracture stimulation activities. The LoR, rationale for analysis, and limitations of key analytes are presented inTable 4.6.

Table 4.6 Fracture stimulation additives and breakdown constituents

Analyte Limit ofReporting

Rationale Limitations as Indicator



Monoethanolamine(MEA)

1 µg/L Indicator ofmonoethanolamineborate

Used in several other applications in industry, forexample surfactant, detergents and textiles.Ethanolamine is used in herbicides and is present inurine secreted by mammals, thus native animals andgrazing livestock may be a source of detectablebackground concentrations in surface water andgroundwater.

THPS 50 µg/L(±50 µg/La)

Compound – fracturestimulation additive

THPS degrades rapidly (within 7 days) throughhydrolysis, oxidation, and photo-degradation.Degradation time in flowback water and producedwater (deep groundwater) is expected to be longer.Oxidation and photolysis will effectively degradeTHPS in surface waters. New methodology foranalysis of THPS with high level of uncertainty at thePQL level (±50 µg/La)

Free chlorine 0.2 mg/L Indicator of sodiumhypochlorite

Free and total residual chlorine concentrations withinfracture stimulation mix may typically be belowdetection limits. Free chlorine and total residualchlorine are products associated with the chlorinationof water supplies and may influence concentrationswithin surface stream monitoring points where thisproduct has been introduced.

Total residualchlorine

0.2 mg/L Indicator of sodiumhypochlorite

(a) Envirolab (2015)

4.6 Water volumesThe extracted volumes of flowback and produced water are recorded by a flowmeter at each pilot well site.Flowback volumes were only recorded for pilot wells WK12 and WK13 during December 2014 as WK11 andWK14 were not yet commissioned.

4.7 Assessment criteria and trigger responseThe criteria used for the assessment of monitoring data follows the protocols provided in the SGMP. Specificanalyte trigger values at this stage in the Project are not considered appropriate due to the natural variabilityin groundwater and surface water quality at different locations across the site and at different depths in thegeological strata. There are also insufficient sampling events to build up enough confidence/statisticalsample pool to enable setting trigger threshold values as described in ANZECC (2000). Instead, generaltrigger criteria are used to assess monitoring sites as follows:

n Water level and water quality trends of individual or groups of analytes where the trends are distinctlyrelated to pilot well activities. Water level response, i.e. drawdown, is attributed to depressurisationactivities and provides a measure of potential connectivity between deep coal seams and the overlyingshallow rock and alluvial water resources. The water quality triggers are defined as a distinct deviationfrom typical observed trends in water quality that can be related back to pilot well activities.

n Change in beneficial use of an aquifer by applying the beneficial use matrix designed within the SGMP.The aquifer type refers to the alluvial and shallow fractured rock systems. The change in beneficial useis determined from a review of yield and water quality characteristics (namely EC as an indicator ofsalinity) over the time period.

n Water quality trends associated with fracture stimulation additives and relevant breakdown/elementalconstituents as key analytes within surface water and groundwater. To be monitored as part of theflowback and produced water monitoring program. The fracture stimulation additives readily dissolveand dissociate into intermediate products or elemental constituents.



The surface water monitoring data is also compared against default ANZECC (2000) guideline values for theprotection of freshwater aquatic ecosystems (Appendix D). This assessment is undertaken so as to providean understanding on whether other land use practices (such as agriculture) or natural background conditions(e.g. geological or evaporative hydrological processes) have influenced surface water quality.

The SGMP provides trigger management response protocols to be adopted for confirmed or possiblechanges in water resources or impacts arising from pilot well activities. The response actions/plans would beimplemented by AGL and require review/endorsement by NOW and EPA (as appropriate). These responseaction/plans may include one or more of the following:

n Review the dataset or incident/complaint (if from a private landholder) to identify possible causes.n Implement additional sampling and monitoring as appropriate.n Inspect the bore/river site and interview landowner.n Assess the trend or impacts in terms of local Waukivory operational issues (such as flowback/produced

water volumes, performance of individual wells, workovers, timing of events etc).n Conclude whether the trend or impact is, or is not, attributed to a CSG activity.n Advise NOW and EPA (where appropriate) and recommend a course of action if trend is or is possibly

attributable to the Project.



5. Water level trends5.1 Groundwater levelsGroundwater level hydrographs for the Waukivory monitoring bores WKMB01, WKMB02, WKMB03,WKMB06A and WKMB06B for the period from February 2012 to December 2014, from baseline monitoringthrough to start of flowback following fracture stimulation of pilot wells WK11, WK12, WK13 and WK14, areshown in Figure 5.1a. A snapshot of the groundwater response from the bores over the period October 2014to December 2014 is shown in Figure 5.1b. The spikes depicting rapid groundwater level decline followed byrecovery on the hydrographs are associated with water sampling events. Manual groundwatermeasurements in private monitoring bore GW080487 are shown in Figure 5.1a and Figure 5.1b. Piezometriclevels in multizone monitoring well WKMB05 for the period November 2014 (installation) to 31 December2014 are shown in Figure 5.4. Piezometric levels in vibrating wire piezometer PL03 are shown in Figure 5.5.A description of the groundwater level responses before, during and after the fracture stimulation program inthe different hydrogeological units is provided below.

5.1.1 Alluvium

Groundwater levels in monitoring bore GR-P3 show a notable response to relatively high rainfall events(Figure 5.1a). This is a threshold response, with rainfall events of a certain magnitude required to trigger aresponse in groundwater levels. The hydrograph for GR-P3 shows groundwater levels decreasing over twoto three months following a significant period of rainfall as shallow groundwater is lost to baseflow orevapotranspiration.

During the baseline monitoring period (March 2014 to December 2014) groundwater levels in GR-P3increased by about 0.2 m in response to the rainfall event in August 2014. Groundwater levels then declinedby about 0.2 m over the next three months until November 2014.

The monitoring bores GR-P3 and WKMB06A show a rapid recovery of groundwater levels in response tosampling events, which is indicative of the typically high hydraulic conductivity of the alluvium.

Groundwater levels in alluvial monitoring bores GR-P3 and WKMB06A show no response attributable to thefracture stimulation of the pilot wells in October and November 2014, or the commencement of pumpingduring the initial flowback period in December 2014 (Figure 5.1b).

5.1.2 Shallow rock

Groundwater levels in the monitoring bores WKMB01 and WKMB02 show a response to high rainfall events,with a response time as rapid as the response seen in alluvial bore GR-P3 (Figure 5.1a). This response torainfall is not observed in the shallow rock monitoring bores across the wider Gloucester Basin monitoringnetwork (Parsons Brinckerhoff 2013a).

The pressure transducer dataloggers at WKMB01 and WKMB02 failed to record between March 2014 andAugust 2014 during the baseline monitoring period. Groundwater levels in WKMB02 increase by about 0.2 min response to the rainfall event in August 2014, and then decrease by about 0.2 m over the next threemonths to November 2014.

The monitoring bores show a slower recovery response to sampling events, indicative of the lower hydraulicconductivity of the shallow rock unit.



Groundwater levels in monitoring bores WKMB01, WKMB02 and WKMB06B show no response attributableto fracture stimulation of the pilot wells in October and November 2014, nor the commencement of pumpingduring initial flowback in December 2014 (Figure 5.1b).

Manual groundwater measurements at private monitoring bore GW080487 screened in the shallow rock donot show a significant change in groundwater levels over the monitoring period (Figure 5.1a). Groundwaterlevels decrease by approximately 0.3 m from March 2014 to September 2014 during the baseline monitoringin response to a period of below average rainfall. Groundwater levels in GW080487 show no responseattributable to fracture stimulation of the pilot wells in October and November 2014, nor the commencementof pumping during initial flowback of the pilot wells in December 2014 (Figure 5.1b).

5.1.3 Interburden of deeper coal measures

Groundwater levels in monitoring bore WKMB03 screened in the interburden (and thrust fault zone) do notshow a response to individual rainfall events (Figure 5.1b).

Groundwater levels at WKMB03 show a general decreasing trend during the baseline period (March 2014 toDecember 2014) with an overall reduction of about 0.5 m. A distinctive delayed recovery response tosampling events is evident, which is indicative of very low hydraulic conductivity within the interburden/faultzone. Following sampling events the groundwater levels are estimated to take about 2 weeks to recover. Thegroundwater levels did not have sufficient time to fully recover following sampling events during Novemberand December 2014, and therefore it was not possible to determine any underlying groundwater trendsduring that period.

Groundwater levels in monitoring bore WKMB03 show no response attributable to fracture stimulation of thepilot wells in October and November 2014, nor the commencement of pumping during initial flowback inDecember 2014 (Figure 5.1b). Despite the difficulty in assessing groundwater level trends in this bore duringthe period October 2014 to December 2014 (due to the intensive sampling program) the general decreasingtrends in groundwater levels that were observed prior to the fracture stimulation continue throughoutNovember and December which is generally consistent with observations in WKMB01, WKMB02 andGW080487 during this period.



Figure 5.1 Groundwater levels and rainfall at the Waukivory monitoring bores



5.1.4 Deep groundwater

Deep groundwater (>300 mbgl) is monitored by WKMB05 (multizone monitoring well) and PL03 (vibratingwire piezometer). A comparison of WKMB05 monitored intervals to WK13 perforated intervals is shown inTable 5.1 and Figure 5.2. The westerly dip of geological strata is such that coal seams intersected byWKMB05 are intersected at a greater depth in WK13 which is located 164 m to the west. A plot of sensordepth against pressure (metres H20) for WKMB05 is shown in Figure 5.3. Piezometric levels in WKMB05 forthe period November 2014 (installation) to 31 December 2014 are shown in Figure 5.4. Piezometric levels inPL03 for the September 2013 (installation) to 31 December 2014 are shown in Figure 5.5.

Figure 5.3 shows that WKMB05 sensors 1 to 4 align closely to the hydrostatic pressure profile, with theincrease in pressure at sensors 3 and 4 indicating that there is an upward vertical gradient at depth. This isto be expected as the centre of a Basin where WKMB05 is located. Preliminary regional numerical modellingfor the Basin indicates that an approximately 10 m increase in pressure head at a depth of about 600 mbgl,where sensors 3 and 4 are located, can be expected. Piezometric levels in sensors 1 to 4 vary from about 5m above ground level (sensor 1) to about 17 m above ground level (sensor 4) (Figure 5.4).

Piezometric levels in WKMB05 sensors 5 and 6 are about 45 m and 70 m respectively above ground level(Figure 5.4). Sensors 5 and 6 show a pressure that is higher than the hydrostatic profile and the modelledhydrostatic profile at this location (Figure 5.3). These sensors appear to be influenced by a different pressuresource and would be consistent with influence from the deep fracture stimulation at WK13. WKMB05 islocated 164 m east from pilot well WK13, which was fracture stimulated between 27 October 2014 and 5November 2014 prior to the installation of the WKMB05 sensors. Sensors 5 and 6 are installed at the samedepth (mbgl) as perforated intervals in WK13 (Figure 5.2), and are installed in the fault thrust zone, not in acoal seam that has undergone fracture stimulation. It is important to note that sensors 1 to 4 do not recordany anomalous pressures above the expected hydrostatic profile. Sensors 1 to 4 are not installed at thesame depth (mbgl) as perforated intervals in WK13, and sensors 2 and 4 are installed in coal seams thathave been perforated in WK13 (Figure 5.2). This suggests that pressure effects are depth restricted and thepropagation of depressurisation effects vertically and along coal seams is limited relative to the lateralpropagation.



Figure 5.2 Schematic comparison of WK13 perforated intervals and WKMB05 monitored intervals



Table 5.1 Comparison of WK13 perforated intervals and WKMB05 monitored intervals

WK13 WKMB05

Sensor Perforated interval(mbgl)

Coal seam Sensor Monitored interval(mbgl)

Formation

1 340.0 – 343.0 Leloma Formation –Interburden

10 404.5 – 408.4 Bindaboo

2 426.0 – 429.0 Jilleon Formation –Cloverdale Coal Seam

9 451.4 – 474.0 Cloverdale

8 514.5 – 523.3 Roseville (upper)

7 540.2 – 575.1 Roseville (lower)

3 584.0 - 587.0 Jilleon Formation –Interburden

4 595.4 – 598.4 Jilleon Formation –Fairbairns Coal Seam

6 612.2 – 628.8 Fairbairns Lane (upper)

5 694.1 – 738.3 Fairbairns Lane (lower) 5 698.5 – 701.5 Jilleon Formation –Interburden

6 711.0 – 714.0 Jilleon Formation –Interbuden (fault zone)

4 Not perforated Glenview

3 812.5 – 826.5 Glenview

2 878.7 – 911.4 Avon

1 934.2 – 946.3 Triple



Figure 5.3 Sensor depth (mbgl) vs sensor pressure (mH20) at WKMB05

The rapid changes in the piezometric levels measured at all sensors on 25 November 2014 occurred duringthe commissioning of the packer system. Piezometric levels have since begun to re-equilibrate to that of themonitored formations. Sensors 1, 2 and 4 show relatively stable trends within 2 to 3 days of installation on25 November 2014. Sensor 2 has shown an initial increase until the end of November followed by adeclining trend that has persisted for the remainder of the monitoring period whereas sensors 5 and 6 showa rising trend throughout the monitoring period. The time required for the piezometric pressure at the sensorto equilibrate to that of the surrounding formation is typically longer for lower permeability formations.



Figure 5.4 Groundwater levels and rainfall at multizone monitoring well WKMB05

Vibrating wire piezometer PL03 was installed in September 2013 (Figure 5.5). Interburden sensor 3(463 mbgl) shows a decrease in piezometric pressure of about 60 m since installation. Coal seam sensor 2(496 mbgl) shows a decrease in piezometric pressure of about 20m since installation. These declines reflectthe long term readjustment of pore pressure in the surrounding rock since installation and do not representnatural trends. This long recovery is due to the very low permeability of the interburden and coal seams atthe depth of the sensors. This phenomenon is widely observed in VWP installations and has been observedat VWP’s installed at the AGL Hunter Gas Project. At that location, groundwater levels took over one year toequilibrate following installation (Parsons Brinckerhoff, 2014e).

There is a small sudden drop in piezometric pressure of approximately 2 m at PL03 sensor 2 that occurredon 17 November 2014. Although the pressure change coincides with the fracture stimulation period, thenature of the change is inconsistent with the injection of fluids at the gas wells (which would cause a numberof pressure increases), and no response is observed during the start of the flowback period. The apparentpressure change is therefore attributed to a slight malfunction of the datalogger. There have been a series ofsmall variations in piezometric level at PL03 sensor 3 throughout the dataset that do not correlate withrainfall, and cannot be attributed to fracture stimulation.



Figure 5.5 Groundwater levels and rainfall at vibrating wire piezometer PL03

5.1.5 Vertical hydraulic gradients

Groundwater levels at the WKMB06A and WKMB06B nested monitoring site show an upward verticalgradient of about 0.2 m between the shallow rock and the alluvium although levels are slightly lower than thewater table in the alluvium at GR-P3 (Figure 5.1). This is consistent with the conceptual hydrogeologicalunderstanding whereby deeper groundwater migrates through the shallow fractured rock and into thealluvium before mixed shallow and deep groundwater discharges to surface waters.

Groundwater levels at WKMB03 within the interburden of the deeper coal measures are higher than in theshallow rock monitoring bores WKMB01, WKMB02 and WKMB06B and indicate an upward vertical gradientof about 2 to 3 m and probable confining conditions attributed to the low permeability rock. Vertical seepageis likely to be limited and slow due to the low permeability of the interburden units.

Piezometric levels at WKMB05 sensors 1 to 4 show an upward vertical gradient. This gradient is about 12 mfrom sensor 4 (at about 600 mbgl) to sensor 1 (at about 340 mbgl). WKMB05 sensors 4 and 5 showanomalously high piezometric levels of about 45 m and 70 m respectively above ground level. Thesesensors are considered to be affected by a different pressure source such as deep fracture stimulation, andconsequently cannot be used to assess regional recharge and discharge trends at this time.

An upward vertical component of hydraulic gradient is characteristic of groundwater discharge areas.

5.2 Surface water levelsSurface water levels are recorded by dataloggers at the Waukivory stream gauges. Data for the periodSeptember 2014 (stream gauges installed) to 31 December 2014 are shown in Figure 5.6.



Water levels at stream gauge sites WKSW01 (Avon River upstream), WKSW02 (Waukivory Creek upstreamof the Project site) and WKSW03 (Avon River downstream of the Project site) have shown an overallreduction between September 2014 and mid December 2014 due to the very low rainfall over this period.Water levels are close to the zero gauge height at each site between September 2014 and mid December2014, and are likely to be representative of ponded water. Periods of very low rainfall and low water levels inthe Gloucester Basin result in ‘no flow’ or ‘very low flow’, when the Avon River and its tributaries arecharacterised by multiple disconnected pools (Parsons Brinckerhoff 2013a).

The level sensor in the datalogger failed to record at WKSW01 between 30 September 2014 and12 November 2014, and from 29 November 2014 onwards. The level sensor in the datalogger failed atWKSW02 between 18 September 2014 and 29 October 2014. Water levels at WKSW02 and WKSW03 showan increase of about 1 to 2 m in response to the rainfall events in December 2014 (Figure 5.6).

Water levels at the Waukivory stream gauge sites show no response attributable to fracture stimulation of thegas wells in October and November 2014, or the commencement of pumping during initial flowback inDecember 2014 (Figure 5.6).



Figure 5.6 Surface water levels and rainfall at the Waukivory stream gauges



6. Water quality6.1 IntroductionThis section presents water quality monitoring data for the baseline period (March to October 2014) and thefracture stimulation and flowback period up until 31 December 2014. The water quality assessment isdescribed for the following components within this chapter:

n Groundwater quality monitoring resultsn Surface water quality monitoring resultsn Environmental isotopesn Fracture stimulation fluid and raw water compositionn Fracture stimulation additivesn Aquifer beneficial use assessment.

A comprehensive suite of elements and compounds were analysed in each sample (Section 4). Completeanalyses are presented in Appendix D and time series data for each analyte is graphically presented inAppendix E. The ALS and Envirolab Services (for analysis of THPS) laboratory reports are provided inAppendix F and isotope analyses in Appendix G. In the body of this report, discussion focusses on a subsetof analytes that are considered to be general indicators of water quality, as well as the set of key analytesassociated with fracture stimulation fluid additives. These are outlined in Table 6.1.

Table 6.1 Groundwater quality parameters discussed in this report

General indicator analyte Justification

Physico-chemical parameters EC and pH General indicator of water quality and indicator of the transition fromflowback to produced water (by an increase in EC)

pH is an Important indicator of water quality

Major ions General indicators of water quality and type. Sulphate may be abreakdown product of THPS in fracture stimulation fluid

Dissolved metals: iron, zinc, boron andstrontium

Naturally occurring metals with the highest natural concentrations ingroundwater and/or showing most variation in baseline period. Boronis present in fracture stimulation fluid as MEA-borate

Nutrients Indicators of land use practices. Phosphorous is a breakdown productof THPS in fracture stimulation fluid. Total nitrogen is a break-downproduct of MEA in fracture stimulation fluid. These nutrientcompounds may therefore be weak indicators of fracture stimulationfluids.

Dissolved gases (methane) Naturally occurring in groundwater. Trends observed during baselineand fracture stimulation

Dissolved hydrocarbons: BTEX compounds Naturally occurring in groundwater; not present in fracture stimulationfluid, however of public concern.

Dissolved hydrocarbons: Phenoliccompounds – phenol, 3-&4- methylphenol, 2-methylphenol (groundwater only)

Naturally occurring in groundwater; not present in fracture stimulationfluid.

Key analytes: fracture stimulation additives



General indicator analyte Justification

Monoethanolamine (MEA) Fracture stimulation additive

THPS Fracture stimulation additive

Free chlorine Breakdown constituent of sodium hypochlorite. Although not used asa fracture stimulation additive by AGL during the Project, sodiumhypochlorite (and its breakdown constituents) is still listed in EPL20358 and therefore is discussed in detail in this report.

Total residual chlorine Breakdown constituent of sodium hypochlorite. Although not used asa fracture stimulation additive by AGL during the Project, sodiumhypochlorite (and its breakdown constituents) is still listed in EPL20358 and therefore is discussed in detail in this report.

6.2 Groundwater qualityGroundwater quality data have been assessed using time series plots to identify water quality changes andtrends with reference to the baseline (pre-fracture stimulation) period. The baseline and operationalmonitoring data so far collected are insufficient to determine statistical trends with a high degree ofconfidence, and therefore the exponentially weighted moving average (EWMA) and Mann Kendall (MK) trendstatistics have not been used in this report.

6.2.1 Physico-chemical parameters

The following section discusses salinity (measured as EC) and pH data collected at the groundwatermonitoring bores during 2014. Field pH data has been presented because it is generally considered the mostreliable as the pH of water samples can vary following collection due to degassing of CO2 from the sample.Whereas the laboratory EC data is presented, as this data is considered more reliable than fieldmeasurements due to the precise instrumentation used in accredited laboratories.

Time series data of laboratory EC and field pH are presented in Figure 6.1 and Figure 6.2 respectively.

6.2.1.1 Electrical conductivity

Groundwater sampling over the baseline period indicates that groundwater in the alluvium is fresh tobrackish, and groundwater in the shallow rock is marginal to slightly saline.

During the fracture stimulation and initial flowback periods the EC of groundwater samples declined in allmonitoring bores, most notably WKMB01, compared to the baseline data. Most bores were subject to adecline in EC through the early 2014 baseline data gathering period.



Figure 6.1 Groundwater laboratory EC

6.2.1.2 pH

The pH of groundwater samples were generally similar to baseline conditions, although were below thebaseline range for some sampling events at GR-P3, GW080487 and WKMB02. Groundwater samples in thealluvium and shallow rock have a near neutral pH with the exception of GW054940 (one sample available,results in Appendix D) and WKMB02, which are classified as moderately alkaline and alkaline respectively.

Water quality data for samples collected from WKMB03 (and to a lesser extent WKMB02) indicate thepossible influence from cement grout during bore construction. Interaction with grout can cause unusuallyhigh pH (> 10), high dissolved silica, and high alkalinity (Bartos and Ogle 2002). The high pH of water affectsgroundwater chemistry, including dissolved metals (such as zinc).



Figure 6.2 Groundwater field pH



6.2.2 Major ions

The major ion characteristics of groundwater samples are shown in piper diagrams for the baseline period inFigure 6.3 and for fracture stimulation and initial flowback in Figure 6.4.

A piper diagram is a graphical representation of the relative concentrations of major ions (Ca2+, Mg2+, Na+,K+, Cl-, HCO3

- and SO42-), and is used to distinguish the chemical profile of major water types.

Figure 6.3 Major ion chemistry of groundwater during baseline

Groundwater in the shallow rock aquifer is dominated by sodium, chloride and bicarbonate. Groundwater inthe alluvium has a more mixed cation (Mg, Ca) composition than groundwater in the shallow fractured rock.

Figure 6.4 Major ion chemistry of groundwater during fracture stimulation and flowback

Water samples taken during the fracture stimulation and flowback period indicate no change in water typecompared to the baseline assessment period.



6.2.3 Dissolved metals

Concentrations of dissolved metals for the baseline period are presented in Figure 6.5. The major findings fordissolved metals in the baseline period are as follows:

n Generally dissolved metal concentrations in the shallow rock aquifer are similar to groundwater in thealluvium at GR-P3.

n Metal concentrations are within the expected range for groundwater in the Gloucester Basin.

n Beryllium, mercury and vanadium were below the laboratory LoR in all groundwater samples. Cobaltwas below LoR in the shallow rock aquifer. Cadmium, chromium and lead were below LoR in thealluvium.

Figure 6.5 Dissolved metal concentrations in groundwater

During fracture stimulation and initial flowback there were no noticeable trends in the concentrations reportedfor most of the 21 metals included in the dissolved metal analytical suite. Time-series plots of concentrationsfor all metals within the sampling suite are provided in Appendix E. In most monitoring bores the ranges indissolved metal concentrations remained similar to baseline values and changes in concentration data wasdeemed to represent natural variability.

For dissolved iron, zinc, strontium and boron, variations in concentrations over the monitoring period aredescribed below (see Figure 6.6 to Figure 6.9).

n Iron – WKMB06A shows an apparent rising trend from 5.27 to 15.2 mg/L and was only sampled duringfracture stimulation activities. Concentrations of iron in WKMB06A will be tracked as part of futurescheduled periodic monitoring. This monitoring will assess if this is a continuous trend or potentiallyrelated to the recent construction of the bores and associated aquifer disturbance. The fracturestimulation fluid concentrations ranged from 0.11 mg/L to 0.243 mg/L; lower than the backgroundconcentrations in groundwater.

n Zinc – Concentrations of zinc in groundwater are typically low in most monitoring bores. Theconcentration of zinc in WKMB03 is at least one order of magnitude higher than other monitoring bores.This is attributed to the possible influence of grout during the construction of the bore, and not hydraulicfracturing activities. The small scale background variability in the concentration of zinc in WKMB03 ishighlighted by the period of high frequency sampling throughout November and December 2014.

n Strontium – Strontium concentrations decreased slightly at all sites over the monitoring period with theexception of private bore GW080487. Elevated concentrations are noted at GW080487 for backgroundand fracture stimulation events with an overall rising trend from 3.1 mg/L (13 March 2014) to 5.8 mg/L



(22 December 2014). This bore is located approximately 1.9 km from the nearest pilot well (WK11). Theconcentration of strontium is much higher (typically >1 mg/L) in groundwater than in the fracturestimulation fluid (<0.2 mg.L).

n Boron – Background boron concentrations in groundwater range from <0.05 – 0.11 mg/L during thebaseline monitoring period. During the fracture stimulation phase boron concentrations peak on 20November 2014 (maximum concentration 0.11 mg/L at WKMB01); however, concentrations remainwithin the baseline range. During the commencement of flowback phase boron concentrations remainwithin background concentrations with the exception of WKMB01 (0.13 mg/L on 22 December 2014).

Figure 6.6 Dissolved iron concentrations in groundwater



Figure 6.7 Dissolved zinc concentrations in groundwater

Figure 6.8 Dissolved strontium in groundwater



Figure 6.9 Boron concentrations in surface water and groundwater

6.2.4 Nutrients

Time-series plots of concentrations for nutrients listed in the sampling suite (Table 4.6) are provided inAppendix E. The major findings for nutrients during the baseline monitoring period are as follows:

n Total nitrogen concentrations in groundwater during the baseline phase range from 0.1 mg/L to 43.3mg/L. There are no trends in groundwater or surface water concentrations during the fracturestimulation and commencement of flowback phases.

n Nitrate concentrations are low at less than 0.5 mg/L. No trends in concentration are noted over themonitoring period.

n Ammonia concentration in shallow groundwater is typically low (< 0.7 mg/L) except for WKMB03 inwhich ammonia (as N) is more elevated, ranging between 14.8 and 36.7 mg/L, and declining over themonitoring period.

n Background concentrations of total phosphorus in groundwater range from <0.01 mg/L (below detectionlimits) to 0.4 mg/L.

n Total phosphorus is present in groundwater at concentrations less than 0.22 mg/L at all monitoringbores during the baseline period. During the fracture stimulation and flowback phases the maximumconcentrations were found in WKMB06A and WKMB06B, which showed concentrations of up to 0.46mg/L and 0.87 mg/L respectively.

n Reactive phosphorus concentrations are less than 0.3 mg/L in monitoring bores and in general theconcentrations are slightly higher than in surface water.

Excluding WKMB03 with elevated values (above 30 mg/L), the background concentrations of ammonia areconsidered natural as higher concentrations in groundwater are expected due to the reducing conditions thatexist at depth. Ammonia concentrations (as N) in groundwater (≤ 0.7 mg/L typically) are generally higherthan that measured in the fracture stimulation fluid (maximum 0.34 mg/L in WK14 sample)



In aqueous solutions ammonia (NH3) gas always exists in a pH dependent equilibrium with aqueousammonium ion (NH4+). Concentrations of NH3 at the same temperature and pressure, will vary from beingrelatively very low at pH less than 6 to high at pH above 10. Thus the data for monitoring bore WKMB03 withelevated values (above 30 mg/L) for NH3 correlate with this pH profile.

6.2.5 Dissolved gases

A time series plot of dissolved methane concentrations in groundwater is presented in Figure 6.10

Figure 6.10 Dissolved methane (CH4) in groundwater

The major findings for dissolved gases in groundwater are as follows:

n Very low dissolved methane concentrations have been recorded in the alluvial monitoring bores GR-P3and WKMB06A at concentrations ranging from 0.012 to 0.017 mg/L.

n Methane was detected in all bores monitoring the shallow fractured rock throughout the baseline andfracture stimulation period with a rising trend evident at bores WKMB01, WKMB03 and WKMB06B.

n Dissolved methane concentrations are consistently higher in the shallow rock than in the alluvium (GR-P3 and WKMB06A).

n The highest concentrations of dissolved methane in groundwater are noted in WKMB01 and WKMB03in which, a generally increasing trend is apparent over the monitoring period.

The concentration of dissolved methane in groundwater is dependent on a number of factors including thepressure and temperature of groundwater at depth and the presence of methane in the coal measures. Theconcentration of methane in a groundwater monitoring bore can be influenced by the pressure decreasesassociated with pumping or sampling, such that frequent sampling can lead to an increase in dissolvedmethane in the bore (Walker & Mallants, 2014). The apparent increasing trend in dissolved methane



concentration in WKMB01 and WKMB03 is considered to reflect the periodic pressure reductions and thehigh sampling frequency during the Waukivory pilot test period.

6.2.6 Dissolved hydrocarbons

The findings for dissolved hydrocarbons in groundwater are as follows:

n No BTEX compounds were used as additives in the fracture stimulation fluids.

n No benzene (B), ethyl benzene (E) or xylenes (X) were detected in groundwater.

n Toluene (T) was detected at low concentrations in three monitoring bores (WKMB01, WKMB02 andWKMB03) during the baseline period and after the start of fracture stimulation of the pilot wells (Figure6.11). The highest concentration of toluene was measured in a sample taken from WKMB03 (72 µg/L)prior to fracture stimulation program. Although it is too early to detect trends, the limited sampling fromWKMB06B to date has identified toluene concentrations in the range of 27 to 71 µg/L. Detection oftoluene in groundwater in the sedimentary rocks of the Gloucester Basin is common and representsnatural background conditions.

n Polycyclic aromatic hydrocarbons (PAH) were not detected in the fracture stimulation fluid. PAHcompounds were detected at low concentrations in WKMB06A, GR-P3 and GW080487 in severalsampling events during November and December 2014. PAH compounds are naturally present in coaland oil and are occasionally detected in groundwater within coal measures.

n Phenolic compounds (phenol, 2-methylphenol and 3-&4-methylphenol) were detected in the shallowrock aquifer monitoring bores WKMB01, WKMB02 and WKMB03 at low concentrations (<20 µg/L)during and after the baseline period (Figure 6.12 to Figure 6.14). Phenol concentrations were highlyvariable and highest in WKMB03; however no trend in concentration is noted over the monitoringperiod. Phenols and methylphenols (cresols) are major constituents of coal tar and it is common todetect those compounds in groundwater within coal measures and associated sedimentary rocks.Phenols were not detected in the fracture stimulation fluid.

n Total Recoverable Hydrocarbons (TRH) were detected in WKMB01, WKMB02 and WKMB03 (TRH lessthan 350 µg/L) during the baseline period. Hydrocarbons are naturally occurring in Permian coals(Volk et al. 2011) and they were detected in sedimentary rocks in the Gloucester Basin during earlyexploration programs (Thornton 1982; Hunt et al. 1989).



Figure 6.11 Toluene concentrations in groundwater

Figure 6.12 Phenol concentrations in groundwater



Figure 6.13 3-&4-methylphenol concentrations in groundwater

Figure 6.14 2-methylphenol concentrations in groundwater



6.3 Surface water qualitySurface water quality data collected during 2014 is presented and discussed in the following section. Waterquality sampling was undertaken during the baseline and fracture stimulation phases only (Figure 4.1) as perthe monitoring frequency stipulated in EPL 20358.

6.3.1 Physico-chemical parameters

The following section discusses salinity (measured as EC) and pH data collected at WKSW01, WKSW02and WKSW03 during 2014. Field pH data has been presented because it is generally considered the mostreliable as the pH of water samples can vary following collection due to degassing of CO2 from the sample.Whereas the laboratory EC data is presented, as this data is considered more reliable than fieldmeasurements due to the precise instrumentation used in accredited laboratories.

6.3.1.1 Electrical conductivity

Sampling of surface water locations during the baseline period indicates that surface water is typically fresh(EC 263 to 981 µS/cm) (Figure 6.15), although salinity spikes are known after large rainfall associated withfirst flush runoff events.

Surface water salinity typically shows an inverse relationship to rainfall and water level due to evaporativeconcentration during dry periods and dilution following rainfall events as relatively fresh runoff is routed intostreams (Figure 6.15). However, during the initial phase of a rainfall event an increase in EC is often seendue to salt loading as readily dissolvable salts are flushed from the ground surface and shallow soils. Thisinitial increase is followed by a decrease in EC as further rainfall runoff increases dilution. This response ismost pronounced in WKSW01 and WKSW03 and can be observed in Figure 6.15 during December 2014.

The Waukivory stream gauges show no change in salinity attributable to the fracture stimulation of the pilotwells in October and November 2014, nor the commencement of pumping during initial flowback inDecember 2014 (Figure 6.15). Continuous EC logger data at WKSW03 indicates a large variation in ECwhich appears to be characteristic of this site, particularly during low flow conditions when the stream ischaracterised by multiple interconnected pools. For example, a sharp increase in EC at WKSW03 ofapproximately 500 µS/cm is noted at the end of November 2014. The same increase is not seen inlaboratory measured EC of a sample collected at this time, which shows that there is spatial variation in ECat small scales at the monitoring points and that, on the whole, the EC of the stream does not displayanomalous behaviour over the monitoring period. These local and transient anomalies are attributed to localgeomorphological processes such as movement or erosion of sediment around the logger.



Figure 6.15 Surface water laboratory and logger EC

6.3.1.2 pH

Surface water is of near-neutral pH and was within the guideline range (pH 6.5 to 8.0) during the baselineperiod (Figure 6.16).

Surface water pH values remained similar to baseline conditions, except for an apparent high pH recordingat WKSW03 on 27 November 2014 (pH 8.67). It is noted that the corresponding laboratory measurement ofpH for the same sampling event was within the normal range (pH 7.57).



Figure 6.16 Surface water field pH

6.3.2 Major ions

The major ion characteristics of surface water samples are shown below in a piper diagram for the baselineperiod (Figure 6.17) and fracture stimulation phase (Figure 6.18). Surface water samples are typicallydominated by sodium and chloride with minor bicarbonate, calcium and magnesium. There was nosignificant change in major ion water type during the fracture stimulation period.

Figure 6.17 Major ion chemistry of surface water during baseline



Figure 6.18 Major ion chemistry of surface water during fracture stimulation

6.3.3 Dissolved metals

Concentrations of detected dissolved metals in surface water are presented in Figure 6.19. The majorfindings for dissolved metals in the baseline period are as follows:

n Metals are within the expected range for surface water in the Gloucester Basin, based on previoussampling (Parsons Brinckerhoff, 2011).

n Beryllium, cadmium, chromium, mercury, molybdenum, selenium, uranium and vanadiumconcentrations were below the laboratory LoR.

Figure 6.19 Dissolved metal concentrations in surface water

Time-series plots of concentrations for all metals within the sampling suite are provided in Appendix E withexception for iron, zinc, strontium and boron which are provided below in Figure 6.20 to Figure 6.23. In mostinstances the dissolved metal concentrations remained similar to baseline concentrations.



The maximum iron concentration in surface water at WKSW03 was (2.5 mg/L) on 27 June 2014, during thebaseline period. The concentration of dissolved iron in surface water at WKSW02 reached a peak of 3.68mg/L on 20 November 2014, during the fracture stimulation period. Surface water at WKSW01 shows anapparent downward trend in dissolved iron concentration during the fracture stimulation period. Surfacewater monitoring locations therefore display divergent trends with respect to dissolved iron over the fracturestimulation period and those trends are likely related to the development of low-flow conditions in the AvonRiver and its tributaries between September and December 2014 when rainfall was well-below average.

Strontium concentrations increased during the fracture stimulation period, however, values remained withinthe baseline range. The observed increase in concentration of some metals is most likely attributed toevaporative concentration during a period of low rainfall.

Background boron concentrations in surface water range from <50 – 120 μg/L and are lower than theinjected fracture stimulation fluid. Surface water boron concentrations peak at WKSW01 on 19 November2014 (320 μg/L) during the fracture stimulation phase.

Figure 6.20 Dissolved iron concentrations in surface water



Figure 6.21 Dissolved zinc concentrations in surface water

Figure 6.22 Strontium concentrations in surface water



Figure 6.23 Boron concentrations in surface water and groundwater

6.3.4 Nutrients

Time-series plots of concentrations for nutrients listed in the sampling suite (Table 4.6) are provided inAppendix E. Baseline concentrations of ammonia, nitrate, nitrite and reactive phosphorus in surface waterare generally lower than those in groundwater.

There were no noticeable trends or fluctuations corresponding with fracture stimulation activities. For mostsampling events the nutrient concentrations remained similar to baseline values. Reactive phosphorusconcentrations appear to be slightly higher than baseline, however this may be associated with the lowrainfall conditions preceding the sampling events.

Total phosphorus in surface water samples during the baseline period was typically below 0.5 mg/L, exceptfor one sampling event at WKSW01 on 11 March 2014 when total phosphorous was detected at 2.08 mg/L.The concentration of total Phosphorous during the fracture stimulation period remained within the baselinerange at all surface water sites.

6.3.5 Dissolved gases

A time series plot of dissolved methane concentrations in surface water is presented in Figure 6.24. Thefollowing are noted:

n Methane was detected in all but two of the surface water samples throughout the monitoring period.n Baseline values range from 10 to 1,260 µg/L with the highest concentration being recorded at

WKSW03.n Concentrations measured during the fracture stimulation and commencement of flowback periods

ranged from 21 to 1,570 µg/L with the highest value recorded at WKSW02 being just outside of thebaseline range.



Figure 6.24 Dissolved methane (CH4) in surface water

6.3.6 Dissolved hydrocarbons

Dissolved hydrocarbons including BTEX, PAH, phenols and TRH were not detected in surface watersamples during baseline or fracture stimulation monitoring periods.

6.3.7 Comparison with ANZECC guidelines

The ANZECC water quality guidelines specify three protection levels ranging from stringent to flexible,corresponding to whether the condition of the particular ecosystem is:

n of high conservation valuen slightly to moderately disturbed, orn highly disturbed.

The protection level signifies the percentage of species expected to be protected. In most scenarios, the95% protection level trigger values are applied to ecosystems that could be classified as slightly-moderatelydisturbed, including rural streams receiving runoff from land disturbed to varying degrees by livestock grazingor pastoralism. The 80% protection level relates to highly disturbed systems, such as rural streams receivingrunoff from intensive horticulture and urban streams receiving road and stormwater runoff. Given thesedescriptions, the 95% protection level is deemed appropriate for evaluation of surface water quality.

The water quality data from surface water monitoring sites WKSW01 – WKSW03 are compared against the95% protection trigger values as provided in Appendix D. Guideline exceedances are listed below.

n Phosphorus concentrations at the three stream monitoring locations were up to one order of magnitudehigher than the guideline value of 0.05 mg/L during the baseline and fracture stimulation phase. Thehighest concentration analysed was 2.08 mg/L at WKSW01 on 11 March 2014. The elevatedconcentrations are likely to be attributed to the application of fertiliser on nearby pasture and croppingland in the immediate catchment.



n Reactive phosphorus concentrations exceed the guideline value of 0.02 mg/L during the baseline andfracture stimulation phase by up to one order of magnitude (0.2 mg/L at WKSW01 on 11 March 2014),however typically only by half an order of magnitude. The majority of exceedances recorded atWKSW01 and WKSW02 may be attributed to runoff from agricultural land practices.

n Ammonia concentrations were reported with marginally above the guideline value of 0.02 mg/L atWKSW01, however there are occasional exceedances of one order of magnitude at WKSW02 onWaukivory Creek. The highest exceedance was 0.98 mg/L at WKSW02 on 27 June 2014. Theconcentrations are likely to be attributed to the application of fertiliser on nearby pasture and croppingland in the immediate catchment.

n Total nitrogen concentrations exceed the guideline value of 0.05 mg/L at all three stream monitoringlocations. These elevated concentrations are attributed agricultural land practices.

n Total residual chlorine concentrations in surface water, measured in the field, average 0.12 mg/L,exceeding the guideline level of 0.003 mg/L at all three stream monitoring throughout the monitoringperiod. The highest recorded was 0.50 mg/L at WKSW03 on 18 November 2014.

n Zinc concentrations exceed the guideline value (0.008 mg/L) by 1 to 2 orders of magnitude at the threesites. The highest concentration analysed was 0.39 mg/L at WKSW01 on 22 October 2014. Theelevated concentrations are generally associated with runoff from both agricultural and urbanlandscapes.

n Copper concentrations are marginally above the guideline value of 0.0014 mg/L at WKSW01 andWKSW02.

n Aluminium concentrations are marginally above the guideline value of 0.055 mg/L at WKSW01 and onesampling event for WKMB03.

6.4 Environmental isotopesThe following Section discusses the analysis of environmental isotopes in samples collected from March toNovember 2014. The following environmental isotopes were analysed:

n Oxygen-18 and deuterium (2H) analysis (GNS Stable Isotope Laboratory, New Zealand)n Strontium 87/86 analysis (Australian National University, ANU)n Tritium (3H) analysis (GNS Tritium and Water Dating Laboratory, New Zealand)n Carbon-13 (13CDIC) and methane isotope analysis (13C-CH4 and 2H-CH4) (UC Davis Stable Isotope

Facility)n Radiocarbon (14C) analysis (Rafter Radiocarbon Laboratory)

Laboratory results are provided in Appendix G.

6.4.1 Stable isotopes

Stable isotopes of water (δ18O and δ2H) provide information about the origin of natural waters and theprocesses that have affected groundwater since it entered the groundwater system.

The Global Meteoric Water Line (GMWL) provides an important key to the interpretation of oxygen-18 anddeuterium data. It is a line that defines the relationship between oxygen-18 (18O) and deuterium (2H) in freshsurface waters and precipitation from a number of global reference sites. Water with an isotopic compositionthat lies on the GMWL is assumed to have originated from the atmosphere and to be unaffected by othergeochemical processes. Samples that plot significantly off the GMWL can indicate fractionation, which is amodification by processes such as evaporation and interaction with rock minerals. The stable isotopecomposition of rain is also influenced by altitude, climatic conditions and rainfall intensity, such that rain fromdifferent locations can plot at different positions along the GMWL.



Stable isotopes of water values are compared to the GMWL.(δ2H = 8.13 δ18O + 10.8) (Rozanski et al. 1993) and the Local Meteoric Water Line (LMWL) (Sydney region)(δ2H = 8.3 δ18O + 16.3) (Crosbie et al. 2012) in Figure 6.25. Stable isotope data is provided in Table 6.2.

A rainfall sample from the Tiedman property was collected on May 2015 (Parsons Brinckerhoff 2014c) and isplotted as modern rainfall in Figure 6.25.

Figure 6.25 Deuterium versus oxygen-18 for groundwater and surface water

Table 6.2 Stable isotope results

Sample ID Sample date Oxygen-18 (‰) Deuterium (‰)

Groundwater

WKMB01 12/3/14 -4.23 -22.4

WKMB01 26/6/14 -4.50 -24.4

WKMB02 12/3/14 -4.43 -22.7

WKMB02 26/6/14 -4.52 -23.9

WKMB03 13/03/2014 -5.50 -30.7

WKMB03 26/06/2014 -5.65 -32.3

GR-P3 12/3/14 -4.62 -23.7

GR-P3 27/6/14 -4.71 -25.2

WKMB06A 18/11/14 -4.77 -26.4

WKMB06B 19/11/14 -4.89 -26.4

Surface water



Sample ID Sample date Oxygen-18 (‰) Deuterium (‰)

WKSW01 11/3/14 -1.84 -2.8

WKSW01 27/6/14 1.50 8.6

WKSW02 11/3/14 -1.42 -2.9

WKSW02 27/6/14 -2.55 -12.9

WKSW03 11/3/14 -0.89 0.7

WKSW03 27/6/14 -0.45 -0.6

The shallow rock bores (WKMB01, WKMB02 and WKMB06B) and the alluvial bores (GR-P3 and WKMB06A)have similar stable isotope values and plot between the LMWL and GMWL, indicating groundwater is ofmeteoric origin. The groundwater samples are notably more depleted with respect to 18O and 2H comparedwith surface water samples and modern rainfall. This is likely a function of the groundwater having a longresidence time (thousands of years) and representing rainfall recharge under different (colder) climaticconditions. These results are consistent with previous monitoring in the GGP area (Parsons Brinckerhoff2014d).

Surface water analyses plot on and to the right of the GMWL, indicating surface water has undergoneevaporative enrichment. This is consistent with the low flow conditions and remnant pools regularly presentat all three surface water locations.

6.4.2 Strontium isotopes (87Sr/86Sr)

Strontium isotope ratios (87Sr/86Sr) can provide important information on water-rock interaction and theprovenance of the aquifer host-rocks. Strontium isotope ratios for groundwater and surface water arepresented in Table 6.3.

Table 6.3 Strontium isotope (87Sr/86Sr) results

Sample ID Sample date 87Sr/86Sr 87Sr/86Sr (SD) Strontium concentrations(mg/L)

Groundwater

WKMB01 12/3/14 0.706433 0.000005 2.990

WKMB01 26/6/14 0.706371 0.000014 2.960

WKMB02 12/3/14 0.706556 0.000005 0.257

WKMB02 26/6/14 0.706542 0.000010 0.233

WKMB03 13/03/2014 0.706641 0.000005 2.53

WKMB03 26/06/2014 0.706619 0.000016 2.12

GR-P3 12/3/14 0.707455 0.000004 2.400

GR-P3 27/6/14 0.707374 0.000016 2.450

Surface water

WKSW01 11/3/14 0.707545 0.000005 0.150

WKSW01 27/6/14 0.707555 0.000014 0.360

WKSW02 11/3/14 0.706885 0.000004 0.321

WKSW02 27/6/14 0.706959 0.000010 0.392



Sample ID Sample date 87Sr/86Sr 87Sr/86Sr (SD) Strontium concentrations(mg/L)

WKSW03 11/3/14 0.707419 0.000004 0.336

WKSW03 27/6/14 0.707367 0.000016 0.526

Strontium 87Sr/86Sr ratios for all baseline samples have a range outside that readily attributable to analyticalprecision, with distinct clustering of values. The method therefore has the potential to provide an importanttracer of water types sampled in the GGP area.

Strontium 87Sr/86Sr ratios for all samples are plotted against Sr concentration in Figure 6.26. Groundwatersamples from the fractured rock monitoring bores have the lowest ratios (least radiogenic: 0.70637 –0.70656), while surface water samples contain more radiogenic Sr (0.70688 – 0.70756) and display a widerrange in ratios. Groundwater samples from the alluvium (GR-P3 and WKMB06A) have 87Sr/86Sr ratios similarto the most radiogenic surface water samples. Based on the current dataset therefore, groundwater from thefractured rock appears to have a distinct low 87Sr/86Sr signature while the surface water and alluvialgroundwater share a similar more radiogenic 87Sr/86Sr signature.

Despite their similar 87Sr/86Sr ratios, groundwater from the alluvium and surface water samples have distinctstable isotope ratios indicating they are not simply the same waters, but rather have acquired similar87Sr/86Sr signatures through dissolution of minerals in the near surface environment.

It is likely that the lower 87Sr/86Sr ratios of WKMB01, WKMB02 WKMB03 and WKMB06B (shallow fracturedrock) reflect interaction of meteoric water with the (less radiogenic) fractured coal measures over millennia,whereas the higher 87Sr/86Sr ratios of the alluvium groundwater and surface water reflect dissolution salts atthe surface and within the soil profile that are ultimately derived from another (more radiogenic) source, viarain, wind-blown aerosols and dust. Salt in aerosols derived from the sea will have 87Sr/86Sr ratios similar tothe modern sea water Sr composition (0.709; Peterman et al., 1970).

Strontium concentrations vary by an order of magnitude in groundwater and surface water, however, there isno trend between strontium concentration and 87Sr/86Sr ratios (Figure 6.26).



Figure 6.26 Strontium isotope ratios (87Sr/86Sr) for groundwater and surface water

6.4.3 Radiocarbon isotopes

Tritium and radiocarbon results are presented in Table 6.4. Carbon-13 of the dissolved inorganic carbonfraction (δ13C-DIC) is also presented in Table 6.4.

Table 6.4 δ 13C-DIC, radiocarbon and tritium results for the upthrust monitoring bores

Sample ID Sample date δ13C (‰) 14C (pMC) 14C agea

(yrs BP)14C ageb

(yrs BP)Tritium (TU)

Groundwater

WKMB01 12/3/14 -15.85 ± 0.2 61.45 ± 0.21 3,849 ± 28 2,300 0.049 ± 0.016

WKMB01 26/6/14 -14.10 ± 0.2 54.24 ± 0.15 4,852 ± 23 2,600 0.034 ± 0.017

WKMB02 12/3/14 -18.93 ± 0.2 39.46 ± 0.17 7,407 ± 34 7,100 0.037 ± 0.016

WKMB02 26/6/14 -17.90 ± 0.2 38.76 ± 0.13 7,550 ± 27 6,900 0.041 ± 0.017

WKMB03 13/03/2014 20.36 ± 0.2 4.34 ± 0.09 25134 ± 165 0.076 ± 0.017

WKMB03 26/06/2014 22.39 ± 0.2 1.23 ± 0.07 35278 ± 474 0.087 ± 0.020

GR-P3 12/3/14 -12.18 ± 0.2 79.32 ± 0.26 1,799 ± 26 Modern 0.313 ± 0.02

GR-P3 27/6/14 -12.36 ± 0.2 79.08 ± 0.18 1,822 ± 19 Modern 0.253 ± 0.022

WKMB06A 18/11/14 -9.94 ± 0.2 89.47 ± 0.23 831 ± 20 Modern 0.245 ± 0.016

WKMB06B 19/11/14 -15.47 ± 0.2 30.12 ± 0.24 9578 ± 63 0.046 ± 0.014

Surface water



Sample ID Sample date δ13C (‰) 14C (pMC) 14C agea

(yrs BP)14C ageb

(yrs BP)Tritium (TU)

WKSW01 11/3/14 -15.18 ± 0.2 99.15 ± 0.30 6 ± 25 Modern 1.456 ± 0.036

WKSW01 27/6/14 -8.64 ± 0.2 102.28 ± 0.21 Modern Modern 1.651 ± 0.043





(a) Uncorrected radiocarbon age.(b) Corrected radiocarbon age.

Radiocarbon ages for the shallow bedrock bores have been corrected to account for potential dilution byprocesses such as carbonate dissolution, sulphate reduction and methanogenesis (as defined in Clark andFritz (1997)). Corrected radiocarbon ages for WKMB01 and WKMB02 range from 2,300 yrs BP to 7,100 yrsBP. There were no significant changes in radiocarbon age between monitoring rounds, and thesegroundwater ages are comparable with previous results (Parsons Brinckerhoff 2014d). WKMB03 yieldedmuch older radiocarbon ages, however both chemical and isotopic evidence (e.g. δ13C) strongly suggest thatsamples from this bore are influenced by soluble components of cement grout. Isotopic ages from this boremay there not be representative of the host groundwater.

Groundwater in the alluvium (GR-P3) and surface water is modern (post 1950), based on radiocarbon dataand the presence of detectable tritium. Tritium concentrations in the alluvium (GR-P3) are just abovebackground levels suggesting that the average age of those samples is approximately 40 to 50 years. Itshould be noted that the indicated ages may reflect mixing between waters of different ages.

6.4.4 Carbon and hydrogen isotopes of methane (δ13C-CH4 and δ2H-CH4)

Compound specific isotopes of dissolved methane (carbon-13 (δ13C-CH4) and deuterium (δ2H-CH4)) wereanalysed in groundwater monitoring bores and surface water samples. Dissolved methane concentrationsand isotope results are presented in Table 6.5. Isotope results were compared with data collected by AGLfrom coal seams during exploration in the GGP area, with results presented in Figure 6.27 and Figure 6.28.

Table 6.5 Dissolved methane concentrations and isotope results

Sample ID Sample date CH4 (µg/L) δ2HCH4 (‰) δ13CCH4 (‰)

Groundwater

WKMB01 12/3/14 4,400 BD -45.69

WKMB01 26/6/14 14,000 NAa NAa

WKMB02 12/3/14 2,640 BD -35.39

WKMB02 26/6/14 4,680 BD -6.79

WKMB03 13/03/2014 not analysed -250.9 -43.35

WKMB03 26/06/2014 13,900 -250.6 -40.73

GR-P3 12/3/14 13 BD -33.70

GR-P3 27/6/14 12 -87.2b -38.91

WKMB06A 18/11/14 12 BD -57.21

WKMB06B 19/11/14 10,300 -209.6 -75.13



Sample ID Sample date CH4 (µg/L) δ2HCH4 (‰) δ13CCH4 (‰)

Surface water

WKSW01 11/3/14 10 BD -43.23

WKSW01 27/6/14 <10 BD -39.95

WKSW02 11/3/14 203 -282.8 -47.61

WKSW02 27/6/14 286 -277.6b -49.46

WKSW03 11/3/14 203 BD -49.47

WKSW03 27/6/14 1,260 BD -47.74

(a) Unreliable lab result(b) Below LOQ;BD – below detection.NA – not available

The carbon-13 (δ13C-CH4) values (see Figure 6.27) indicate that dissolved methane of both groundwater andsurface water is of thermogenic origin.

A comparison of carbon-13 (δ13C-CH4) and deuterium (δ2H-CH4) can provide a more confident identificationof methane origin. Unfortunately deuterium (δ2H-CH4)) could not be analysed for the majority of groundwaterand surface water samples collected during baseline sampling, however a comparison of the few δ2H-CH4

results (for GR-P3 and WKSW02) with δ13C-CH4 values indicate dissolved methane in groundwater andsurface water is of mixed (biogenic and thermogenic) and/or thermogenic origin (Figure 6.28). Isotopeanalysis for methane collected from WKMB06B during the fracture stimulation period indicates that methaneat this location is of biogenic origin.

These results are comparable with the methane isotope data for deep gas wells, and with results forgroundwater monitoring bores sampled for previous studies (Parsons Brinckerhoff 2013b and 2014d). Earlierinvestigations by Pacific Power in 1997 and 2000 (Weber and Smith 2001) identified coals in the GloucesterBasin as medium-volatile bituminous, with a vitrinite reflectance of 0.9% to 1.3%; this is known to befavourable for thermogenic methane generation.



Figure 6.27 Depth versus 13C-CH4

Figure 6.28 13C-CH4 versus 2H-CH4



6.5 Gas wells and produced water6.5.1 Fracture stimulation fluid

Hydraulic fracturing consists of pumping a fluid into a steel cased and cemented wellbore to create enoughpressure to fracture the target coal seam. The fluid contains a proppant, such as sand, carried by a viscousguar gel. The sand helps prop the fractures open to allow gas to be produced to surface. The fracturestimulation fluids used at the gas wells WK11 to WK14, consisted of over 99% water and sand, and less than1% chemical fracture stimulation additives. The water was sourced from Pontilands Dam and stored as ‘rawwater’ in an above ground storage tank on the site of WK13. The total volume of fluid injected during allfracture stimulations was 3.25 ML. The quantity of sand used per gas well ranged from 51 tonnes to 108tonnes.

A summary of the quantities of water and total fluid injected at each well is in Table 6.6.

Table 6.6 Summary of fracture stimulation fluid volumes for each gas well

Constituent WK11 WK12 WK13 WK14

Water in products (L) 3,030 2,406 5,334 2,753

Additives (including water entrained in theproducts) (L)

2,294 1,393 4,267 1,406

Raw (source) water (L) 780,126 476,804 1,507,062 462,376

Total injected fluid (L) 783,156 480,603 1,516,663 466,535

Chemical analysis of the raw water and fracture stimulation fluid are presented in Table 6.7 as ranges for thefour pilot wells. The final injected fracture stimulation fluid contained lower concentrations than groundwaterand surface water of total dissolved solids, major ions, and trace metals. BTEX and some phenoliccompounds were detected in baseline groundwater data, but were not present in the fracture stimulationfluids. Total petroleum hydrocarbons were detected in both groundwater and fracture stimulation fluid at lowconcentrations.

Monoethanolamine (MEA) was present in concentrations that are 2 to 3 orders of magnitude higher in thefracture stimulation mix than in surface and groundwater; however the presence of MEA in groundwater(detected in baseline monitoring) prior to any fracture stimulation activities and raw water during fracturestimulation indicates an alternative source other than fracture stimulation fluid.

THPS was also present in the fracture stimulation mix at concentrations two to three orders of magnitudehigher than the surface and groundwater. However, there are no distinctive trends of this analyte at themonitoring sites which could be attributed to pilot well activities.

Sodium Hydpochlorite was not used as a fracture stimulation additive for the Project.

Laboratory analysis of raw (source) water from Pontilands Dam and fracture stimulation fluid (including thefracture stimulation additives) was undertaken for the fracture stimulation program on each well. The resultsare provided in Appendix D.

Table 6.7 Summary of raw water and fracture stimulation fluid concentrations

Parameter Raw water Fracture stimulation fluid

Monoethanolamine (MEA) Detected in raw water used for WK12hydraulic stimulation (4 µg/L).

Values ranged from 4,200 µg/L to5,690 µg/L.

THPS Detected in raw water used for WK12 Values ranged from 7,800 µg/L to



Parameter Raw water Fracture stimulation fluidhydraulic stimulation (56 μg/L), thisconcentration is within the level ofconfidence of the practical quantificationlimit (PQL) (50 ± 50 μg/L).

13,000 µg/L.

Free and total residualchlorine

Below LoR (0.2 mg/L). Below LoR (0.2 mg/L).

BTEX compounds Below LoR (2 µg/L). Below LoR (2 µg/L).

Boron Concentrations were equal to or less thanthe LoR (0.05 mg/L).

Values ranged from 82.5 mg/L to115.0 mg/L.

Sulphate Low (<1 mg/L to 7 mg/L). Values ranged from <10 mg/L to 63 mg/L.

Total phosphorus Values ranged from 0.07 to 0.12 mg/L. Values ranged from 7.1 mg/L to 16.0 mg/L.

Total nitrogen (as N) Values ranged from 1.3 to 1.6 mg/L. Values ranged from 48.0 mg/L to75.8 mg/L.

Salinity (TDS)a 166 to 214 mg/L 1,840 to 2,590 mg/L

EC Fresh water

242 to 258 µS/cm

Fresh water

470 to 653 µS/cm

pH Near neutral pH(7.07 to 7.80)

Alkaline pH(8.16-9.09)

Major ions Na-Cl / Na-Cl-HCO3 Na -HCO3-Cl

Dissolved metals Below LoR: Sb, Be, Cd, Cr, Co, Hg, Mo,Ni, Se, Sn, U, V

Detected: Al, As, Ba, Cu, Fe, Pb, Mn, Sr,Zn.

Below LoR: Sb, Be, Cd, Cr, Co, Hg, Se, U,V.

Detected dissolved metal concentrationswere typically higher than in the raw water(with the exception of Fe).

Nutrients Ammonia, nitrate and nitrite concentrations(as N) were low (≤ 0.03 mg/L) or belowLoR.

Total organic carbon concentrations werelow (19 mg/L to 24 mg/L).

Ammonia, nitrate and nitrite concentrations(as N) ranged between the LoR (0.1 mg/L)and 0.34 mg/L.

Total organic carbon concentrationsranged between 815 mg/L and 873 mg/L.

Dissolved methane Below LoR (10 µg/L). Below LoR (10 µg/L).

Petroleum hydrocarbons Phenols and PAHs were below LORs.TPH C10-C36 (sum) ranged from below LoR(50 µg/L) to 140 µg/L.

Phenols and PAHs were below LORs. TPHC10-C36 (sum) ranged from below LoR (50µg/L) to 1860 µg/L.

a) The TDS of the fracture stimulation fluid is high compared to the EC because the dissolved solids in the fracture stimulation fluid areorganic and not ionic

6.5.2 Flowback and produced water monitoring

The flowback volumes and percentage recovered up to 31 December 2014 are provided in Table 6.8.Flowback volumes are provided for pilot wells WK12 and WK13 during December following commissioning.WK11 and WK14 were not commissioned until 23 January 2015.

The quality of flowback water has been compared against produced water from gas wells Craven CR06 andWaukivory WK03 sampled in June to October 2014, and is presented in Table 6.9. The flowback watershows distinctively higher concentrations for the following analytes:

n Total organic carbon by over an order of magnituden Phenol compounds by up to 1 order of magnituden BTEX components benzene and toluene by 1 to 2 orders of magnitude.



BTEX compounds were detected in samples from pilot wells WK12 (29 December 2014) and WK13(16 December 2014, 29 December 2014), and in the flowback tank (29 December 2014). The highestdetected concentration of BTEX compounds was in flowback water from WK13. Following receipt andreview of these results, AGL voluntarily suspended the Project. BTEX compounds were not detected inthe raw water supply, nor in the fracture stimulation fluid. In addition, review of sampling and laboratoryprotocols preclude contamination of samples with BTEX during sampling and analysis. The occurrence ofBTEX compounds in the flowback water is the subject of ongoing investigation but is thought to be naturallyoccurring and derived from the deeper coal seams.

Table 6.8 Flowback volumes recovered up to 31 December 2014

Period Ending WK11 WK12 WK13 WK14

Recovered Recovered Recovered Recovered

litres % litres % litres % litres %

31/12/2014 na na 111,293 23.2 376,802 24.8 na na

Note: na = not available

Table 6.9 Flowback and produced water monitoring

Parameter Flowback Produced water (CR06 and WK03)

Monoethanolamine(MEA)

Values ranged from 150 µg/L to 305 µg/L. No data available.

THPS Values ranged from 410 µg/L to 440 µg/L. No data available.


Below LoR (0.2 mg/L). No data available.

BTEX compounds Benzene and toluene reached maximumvalues of 191 and 262 µg/L respectively.Total BTEX ranged between 47 and555 µg/L.

Reported BTEX concentrations were lowand range between below LoR (2 µg/L) to11 µg/L. Total BTEX ranged between 15and 20 µg/L.

Boron Values ranged from below LoR (0.05 mg/L)to 12.7 mg/L.

Values ranged from 0.15 mg/L to0.33 mg/L.

Sulphate Below LoR (10 mg/L) (LoR raised forsulphate analysis on various samples dueto sample matrix).

Concentrations were low and ranged fromthe LoR (1 mg/L) to 14 mg/L.

Total phosphorus Values ranged from 2.63 mg/L to3.64 mg/L.

Concentrations were low and ranged from0.38 mg/L to 1.26 mg/L.

Total nitrogen (as N) Values ranged from 5.4 mg/L to 6.9 mg/L. No data available.

Salinity (TDS) Brackish water(3023 – 5566 mg/L)

Brackish water(2912 – 4385 mg/L)

pH Alkaline(7.15 – 8.74)

Slightly acidic to alkaline(5.73 – 9.63)

Major ions Predominately Na-HCO3-Cl Na-Cl-HCO3

Dissolved metals Below LoR: Be, Cd, Pb, Hg, Se, Sn, U, V.

Detected dissolved metal concentrationswere low with the exception of barium, ironand strontium which reached maximumvalues of 5.95, 2.99 and 5.00 mg/Lrespectively.

Below LoR: Sb, Pb, Hg, Se, U, V.

Detected dissolved metal concentrationswere low with the exception of barium,beryllium, iron and strontium which rangedbetween maximum values of 2.8 and4.3 mg/L and iron with a maximum value of37.8 mg/L.



Parameter Flowback Produced water (CR06 and WK03)

Nutrients Ammonia as N concentrations ranged from2.98 to 5.12 mg/L whilst nitrate and nitriteconcentrations (as N) were at or below theLoR (0.01 mg/L).Total organic carbon concentrationsranged between 332 mg/L and 1010 mg/L.

Ammonia, nitrate and nitrite concentrations(an N) ranged between the LoR (0.01mg/L) and 1.9 mg/L.Total organic carbon concentrationsranged between 9 mg/L and 22 mg/L.

Dissolved methane Methane ranged between 2.42 and9.17 mg/L.

Methane ranged between 6.94 mg/L and13 mg/L.

Petroleum hydrocarbons The phenolic compound 3-&4-methylphenol reached a maximum 166µg/L, the only other phenolic compoundsdetected were 2,4-dimethylphenol, 2-methylphenol and phenol at concentrationsbetween 1.6 and 14.1 µg/L.PAHs were below LORs except for a lowdetection of Naphthalene (1.8 µg/L).All fractions of TPH were detected wherethe C6–C9 fraction registered the highestconcentrations that ranged from 60 to860 µg/L.

Phenolic compounds were below LORs.PAHs were below LORs except for 9compounds with concentrations thatdetected ranging between 1.9 µg/L and17.5 µg/L.

All fractions of TPH were detected wherethe C15-C28 fraction registered the highestconcentrations that ranged from 500 to14400 µg/L.

Note: Formation water quality range is from three sampling events each of gas wells CR06 and WK03 (Parsons Brinckerhoff, 2014f)

6.6 Fracture stimulation additivesAs discussed in Section 4.5, the EPL lists three fracture stimulation additives that require monitoring at thespecified groundwater and surface water locations, and the four gas wells. The listed additives and therelevant breakdown constituents are as follows:

n Monoethanolamine borate (as monoethanolamine (MEA))n Tetrakis (hydroxymethyl) phosphonium sulphate (THPS)n Sodium hypochlorite – free and total residual chlorine.

Sodium hypochlorite was not used during the fracture stimulation program; however the breakdownconstituents of free and total residual chlorine were measured as per the conditions stated in the EPL andare discussed below.

The analytical results are presented in Appendix D. Time series graphs for the key analytes were assessedto determine baseline trends (where there are sufficient data), and changes in concentrations during thefracture stimulation program and subsequent initial flowback phase monitoring period. Table 6.10 contains asummary of key indicator observations. Concentration time series plots are presented in Figures 6.29 to6.32.



Table 6.10 Key analytes – time series observations

Analyte Baseline monitoring period Fracture stimulation period Initial flowback phase

Monoethanolamine (MEA)an Detected in the shallow rock aquifer at

WKMB02 (2 µg/L) and in theinterburden WKMB03 (2 μg/L).

n Detected in surface water at WKSW02(2 μg/L) and WKSW03 (4 μg/L).

n The highest concentration of MEA in water sampleswas detected in the shallow rock at GW080487 (61μg/L) on 13 November 2014. . This concentration isof the same order of magnitude as the highestregional background detections.

n MEA was detected at all monitoring locations on 20November 2014a.

n MEA was detected in two samples (GR-P3 andGW080487) on 9/10 December 2014 at 2 μg/L.

n MEA was detected in surface water and groundwatersamples ranging from 2 to 61 μg/L.

n MEA was not detected in surface wateror groundwater.

n MEA was detected in regionalbackground groundwater and surfacewater samples (from a range oflocations within the Gloucester Basinremote from the Project site). Thesamples were collected on 16, 17 and18 December 2014. MEA was detectedat concentrations ranging from lessthan the LoR to 19 μg/L (Appendix D).

THPS n THPS was not detected ingroundwater or surface water.

n THPS was detected at the following sites:

4 WKSW01 (57 μg/L) (6 November 2014)

4 WKMB03 (57 μg/L) (12 November 2014)4 WKSW03 (59 μg/L) (12 November 2014).

n THPS detections are within the laboratory margin oferror for the LoR uncertainty (50 μg/L ±50 μg/L)b

n THPS was not detected in groundwateror surface water.


n Detected in the interburden (0.9 mg/L),and surface water, at concentrationsranging from <0.2 mg/L to 0.5 mg/L(free chlorine) and <0.2 mg/L to0.6 mg/L (total residual chlorine).

n Detected in the shallow bedrock monitoring boreWKMB06B (0.4 mg/L) on 10 December 2014.

n Detected in surface water; maximum concentrationswere 0.8 mg/L (free chlorine) and 1.1 mg/L (totalresidual chlorine).

n Free and total residual chlorine was notdetected in groundwater or surfacewater.

(a) Samples collected on 20 November 2014 from groundwater close to and distant from the pilot wells, and surface water both downstream and upstream up of the wells detected MEA. MEA was notdetected in the samples collected at the monitoring event after the 20 November 2014 (on 24 November 2014). MEA was detected in some surface water and groundwater sites during baselinesampling in September and October 2014 prior to the commencement of fracture stimulation. A review of sampling and laboratory protocols did not identify contamination of samples. AGL hasprovided information to the relevant regulators on MEA detections.

(b) Envirolab (2015).



Figure 6.29 Monoethanolamine concentrations in surface water and groundwater



Figure 6.30 THPS concentrations in surface water and groundwater (LoR 50 µg/L ±50 µg/L)



Figure 6.31 Free chlorine in surface water and groundwater



Figure 6.32 Total residual chloride concentrations in surface water and groundwater



6.6.1 Tetrakis (hydroxymethyl) phosphonium sulphate (THPS) –phosphorus, sulphate and THPS

THPS is added to fracture stimulation fluids a biocide. An analytical method for the measurement of THPSwas developed by Envirolab specifically for this project, and was approved by the EPA on 19 December2014.

TPHS was not detected in baseline monitoring in groundwater or surface water.

THPS was detected at three isolated locations during the fracture stimulation period; one groundwaterlocation, WKMB03 (57 μg/L on 12 November 2014) and two surface water locations, WKSW01 (57 μg/L on 6November 2014) and WKSW03 (59 μg/L on 12 November 2014). The detections were marginally above theLoR (50 μg/L), and within the margin of error of the LoR (50 μg/L ±50 μg/L) (Envirolab 2015). Concentrationsof THPS up to 100 μg/L may be considered a false positive particularly at levels approaching the LoR (as isthe case for the three detections during fracture stimulation).

THPS was not detected in groundwater or surface water during the initial flowback phase.

Sulphate and phosphorus concentrations (breakdown constituents of THPS) in surface water decreasedduring the fracture stimulation period compared to samples collected during the baseline period (AppendixD).

The trend of sulphate concentrations in groundwater continued to decrease from the baseline period throughthe fracture stimulation to the initial flowback phase. The concentration of phosphorus in groundwaterremained consistent with background levels during fracture stimulation and initial flowback with the exceptionof WKMB06A and WKMB06B. Concentrations of phosphorus in WKMB06A and WKMB06B will be monitoredin future scheduled periodic monitoring. This monitoring will assess if this is a continuous trend or potentiallyrelated to the recent construction of the bores and related aquifer disturbance.

6.6.2 Monoethanolamine borate – boron, nitrogen and monoethanolamine

Monoethanolamine borate is a crosslinker added to fracture stimulation fluids to chemically bind individualgel polymer molecules together to form larger molecules resulting in higher viscosity and better transport ofproppant (sand) (Stringfellow et al. 2014). Monoethanolamine borate is described as non-hazardousaccording to the criteria of National Occupational Health and Safety Commission (NOHSC) and a non-dangerous good according to the criteria of Australian Dangerous Good Code.

The EPA approved the validated methodology for the analysis of monoethanolamine borate asmonoethanolamine (MEA) on 1 December 2014.

MEA was detected in baseline groundwater and surface water samples at concentrations ranging from lessthan the LoR (1 μg/L) to 4 μg/L.

MEA was detected in regional background groundwater and surface water samples (from a range oflocations within the Gloucester Basin remote from the Project site). These samples were collected on 16, 17and 18 December 2014 from monitoring bores located up to 10 km from the Project site. MEA was detectedin these samples at concentrations ranging from less than the LoR to 19 μg/L (Appendix D). There is anegligible likelihood that MEA detected in these samples is associated with the fracture stimulation fluidgiven their distances from the Project.

There is little data published about the distribution of MEA in the environment. There is no readily availableinformation on the concentration and or occurrence of MEA in waters in Australia.



Sources of MEA may be man-made or naturally occurring. MEA is a constituent of a variety of man-madeproducts including surfactants, detergents and cosmetics (Cosmetic Ingredient Review 2012) (Governmentof Alberta 2010). Natural sources of MEA include:

n part of the metabolism process in mammals, with MEA being a constituent of urine; and

n is a suspected by-product of bacteria that are known to exist in groundwater systems.

Consequently it is not unexpected that MEA would be detected in both surface water and groundwater in theGloucester Basin with grazing activities and native animals being a potential source for surface waterdetections; and bacteria a potential source for groundwater detections.

Measurable concentrations of diethanolamine (DEA), which is another alkanolamine and readily biodegradedin the environment to MEA, was detected in groundwater and surface water samples (Appendix D). DEA isused in a variety of industries (not dissimilar to that of MEA) and is readily biodegraded in the environment toMEA (Government of Alberta 2010). Measureable concentrations of DEA ranging from 1 µg/L to 10 µg/Lwere found in baseline samples obtained from monitoring bores located within the Project area. On abroader regional scale within the Gloucester Basin, DEA concentrations ranging between 3 µg/L to 50 µg/Lwere detected in groundwater samples from monitoring bores (TCMB02, S5MB01, FKMB01B, WRMB01B,RMB02, BWMB01C and BWMB01D located up to 10 km from the Project area). Measurable concentrationsof DEA were also detected in baseline groundwater samples from monitoring bores located within the Projectarea.

Four groundwater samples collected during the fracture stimulation period on 12/13 November 2014 hadMEA detections at concentrations of between 4 and 61 µg/L. MEA was not detected in the groundwatersamples collected at the monitoring event on 17 November immediately after the 12/13 November 2014monitoring event (also during the fracture stimulation period) with the exception of WKMB01 which recordedan MEA concentration of 3 µg/L.

All samples collected during the fracture stimulation period on 20 November 2014 from groundwater close toand distant from the pilot wells, and surface water both downstream and upstream of the wells detected MEAwith concentrations ranging between 2 and 60 µg/L. MEA was not detected in the samples collected at themonitoring event on 24 November immediately after the 20 November 2014 monitoring event (also duringthe fracture stimulation period).

A review of sampling and laboratory protocols did not identify contamination of samples.

The two highest concentrations of MEA in water samples were detected in the shallow rock at GW080487(61 μg/L) on 13 November 2014, and at WKMB02 (60 µg/L) on 20 November 2014. The concentrations of allMEA detections (including the 60 μg/L (WKMB02) and 61 μg/L (GW080487)) are within the same order ofmagnitude of the highest regional background detections to date (19 μg/L) (Appendix D). The two higherconcentrations were transient, with the concentration of MEA in the next round of samples taken within sixdays recording a detection of less than the LoR.

Where MEA was detected in surface water and groundwater, THPS concentrations were less than the LoR(50 μg/L ±50 μg/L) with the exception of WKMB03 on 12 November 2014 when the THPS concentration was57 μg/L which is considered within the margin of error of the LoR (refer to Section 6.6.1.)

MEA concentrations were below laboratory LoR in surface water and groundwater samples collected duringthe sampling event undertaken during the initial flowback phase.

AGL has provided information to the relevant regulators on MEA detections.

Boron is a breakdown constituent of MEA. Concentrations of boron in groundwater during the fracturestimulation period were consistent with baseline concentrations. Baseline boron concentrations in surfacewater range from <0.05 to 0.12 mg/L. During the fracture stimulation period, surface water boron



concentrations peak at WKSW01 on 19 November 2014 (0.32 mg/L). WKSW01 is upstream of the Project onthe Avon River. Concentrations of boron in surface water were below laboratory LoR during thecommencement of the flowback phase.

Nitrogen is a breakdown constituent of MEA. There were no clear trends of nitrogen concentrations insurface water (Figure 6.33), with levels demonstrating minor variations from the baseline through the fracturestimulation and initial flowback periods. Concentrations of nitrogen in groundwater were consistent from thebaseline through the fracture stimulation and initial flowback periods; however concentrations of nitrogen inWKMB03 were higher than other groundwater samples and have been shown separately in Figure 6.33.

Figure 6.33 Total nitrogen concentrations in groundwater



Figure 6.34 Total nitrogen concentrations in surface water

6.6.3 Sodium hypochlorite – free and residual chlorine

Sodium hypochlorite was not used during the fracture stimulation program; however the breakdownconstituents of free and total residual chlorine were measured as per the conditions stated in the EPL.

Sodium hypochlorite is used as a disinfectant. When chlorine is added to water in an aqueous sodiumhypochlorite solution, it creates hypochlorous acid. Hypochlorous acid (HOCl) is a weak acid that dissociatesinto hypochlorite ion (OCl–) according to the following equation:

HOCl ↔ H+ + OCl—

Together, HOCl and OCl – are known as free chlorine. The two species exist in an equilibrium that is pHdependent. The equilibrium is also slightly affected by temperature. As the pH increases, the ratio ofhypochlorous acid to hypochlorite ion decreases. Below a pH of 7.5, hypochlorous acid is the dominantspecies. Above a pH of 7.5, hypochlorite ion is the dominant species (HACH 2015).

When ammonia or organic nitrogen is also present, chloramines known as monochloramine, dichloramine,and trichloramine will quickly form. Chloramines are also known as combined chlorine. Total chlorine is thesum of free chlorine and combined chlorine.

The chlorine residual test is used to measure the amount of chlorine remaining in the water at the time thetest is made.

There are three types of chlorine residual which are considered in water treatment.

5. Free chlorine residual – residual consisting of dissolved chlorine gas, hypochlorous acid, andhypochlorite ions.

6. Combined chlorine residual – residual consisting of other forms of chlorine such as chloramines whichare capable of killing bacteria and oxidizing organic matter.

7. Total chlorine residual – the sum of the free chlorine residual and the combined chlorine residual.



Typical levels of free chlorine residual in Australian reticulated drinking water are 0.2 – 0.4 mg/L(NHMRC 2011).

Free chlorine and total residual chlorine was detected at some groundwater and surface water monitoringsites during baseline monitoring indicating a source other than fracture stimulation fluid.

The Surface Water and Groundwater Management Plan (SGMP) states that a response trigger for theWaukivory Pilot Project is a change in beneficial use of an aquifer. An aquifer in the SGMP refers only to thealluvial and shallow fractured rock, as deeper zones are not aquifers and do not host economic groundwaterresources.

A generalised beneficial use matrix is presented in the SGMP, based on yield and water qualitycharacteristics (Table 6.11). It is based on the salinity classification described in the SGMP (AGL, 2014a).Each aquifer can be assigned one or more beneficial use categories (based on cells within the matrix).Beneficial use categories can vary spatially for each groundwater system. The aquifers in the Waukivoryarea rarely yield water at a rate greater than 1 L/s and contain poor water quality with salinities greater than1600 µS/cm.

The electrical conductivity (EC) data on which the beneficial use classification for the Waukivory pilot area isbased is summarised in Table 6.12. All data which is within the 10th percentile and the 90th percentile hasbeen used in the beneficial use classification. A percentile is the value below which a given percentage ofobservations fall. For example, the 10th percentile is the value below which 10% of observations are found.The 10th and 90th percentiles presented in Table 6.12 are used as a method of discounting outlying values.

The following beneficial use categories can be assigned to each of the groundwater systems in theWaukivory area during the baseline monitoring period, as shown in Table 6.11:

n Alluvial aquifers – C2, C3n Shallow rock aquifers – B2, B3, C2, C3, D2, D3.

The following beneficial use categories can be assigned to each of the groundwater systems in theWaukivory area during the fracture stimulation period, as shown in Table 6.11:

n Alluvial aquifers – C2, C3n Shallow rock aquifers – B2, B3, C2, C3, D2, D3.

Water quality monitoring results (specifically electrical conductivity) do not show a change in beneficial usecategory over time from the baseline monitoring period to the fracture stimulation monitoring period andhence a water management response is not triggered.

The beneficial use classification will continue to be assessed during flowback and produced water qualitymonitoring.

Table 6.11 Generalised beneficial use matrix, based on salinity and yield

Yield (L/s)

<5 0.5-5 <0.5

Salinity (µS/cm) 0-800 D+I+S D+I+S D+S A

801-1600 D+I+S D+I+S D+S+In B

1601-4800 I+S+In I+S+In S+In C

4801-10000 S+In S+In In D

10001-20000 In In In E



>20000 F

1 2 3

Key: D – domestic; I – irrigation; S – stock; In – industry

Alluvial baseline Shallow rock baseline

Alluvial fracture stimulation Shallow rock fracture stimulation

Table 6.12 Summary statistics for electrical conductivity during baseline and fracture stimulation waterquality monitoring

Electrical conductivity (µS/cm)

Alluvial Shallow Rock

Field Lab Field Lab

Baseline 10th percentile 3966 4105 880 912

Median 4013 4215 3865 3970

90th percentile 4248 4297 5644 5960

Fracturestimulation

10th percentile 2737 2754 884 862

Median 3821 4090 3739 3870

90th percentile 4013 4105 4920 5048



7. ConclusionsThe following conclusions are drawn from a review of the groundwater and surface water monitoring dataand composition of the fracture stimulation additives for the Waukivory site, during the period of March toDecember 2014. The review included:

n interpretation of water level and water quality trends.

n assessment as to whether trends are naturally occurring or potentially attributed to Project activities.

n assessment of key analytes associated with fracture stimulation additives defined in AGL’s SGMP.

n comparison of monitoring data against default ANZECC (2000) guideline values for protection offreshwater aquatic ecosystems to assess if elevated concentrations exist in the natural environment.

It should be noted that the intensive groundwater sampling during the fracture stimulation and flowbackphases has led to monitoring bores undergoing a greater amount of purging which draws water from thewider formation compared to the less frequent sampling during the baseline phase. This has resulted in morevariability in the datasets for samples collected during these periods.

Groundwater levels

Groundwater levels in the alluvial and shallow rock monitoring bores show distinctive responses to highrainfall events in 2014. This is followed by a gradual decline (recession) period which may continue forseveral months until the next rainfall event occurs.

Groundwater levels in monitoring bore WKMB03 screened in the deep interburden/fault zone do not show aresponse to individual rainfall events. The groundwater level shows a general decreasing trend during thebaseline period of March to October 2014 (which is a broad regional response) due to below average rainfallconditions over the period.

The deep multizone piezometer WKMB05, located 164 m from WK13, shows an increase in piezometrichead with depth as would be expected in the centre of a closed groundwater basin. The deepest two sensorsrecord elevated piezometric pressures consistent with influence from the deepest fracture stimulation zonesin WK13. These observations are consistent with preliminary numerical modelling and also indicate that thepressure influence from fracture stimulation is restricted in the vertical direction (confined).

Groundwater levels in alluvial monitoring bores (GR-P3), shallow rock bores (WKMB01, WKMB02,GW080487 and WKMB06B) and the deep interburden/fault zone bore (WKMB03) show no responseattributable to the fracture stimulation of the pilot wells and the commencement of pumping during initialflowback in December 2014. The nested bore WKMB06A/B installed within the alluvium and shallow rock inNovember 2014 also showed no response from pilot well activities during period of monitoring from 19November through to 31 December 2014.

Groundwater quality

Baseline sampling of groundwater and surface water streams at the Waukivory site occurred in March, June,September and October 2014. Further intense water sampling occurred during the pilot well fracturestimulation and initial flowback periods in November and December 2014. Key conclusions are:

n Monitoring of baseline conditions indicates groundwater within the alluvium is fresh to brackish andgroundwater in the shallow rock is marginally to slightly saline.

n Major ions, dissolved metals and nutrients showed no distinctive trends between the baseline periodand the fracture stimulation/flowback period which may be attributed to pilot well activities. Identified



trends in concentrations are attributed to natural variability over time. The concentration of phosphorusin groundwater remained consistent with background levels during fracture stimulation and initialflowback with the exception of WKMB06A and WKMB06B. Concentrations of phosphorus in WKMB06Aand WKMB06B will be monitored in future scheduled periodic monitoring. This monitoring will assess ifthis is a continuous trend or potentially related to the recent construction of the bores and related aquiferdisturbance.

n Methane concentrations varied considerably between bores, with lowest concentrations in the alluvium.The fractured rock bores showed a rising trend extending from the baseline period through the fracturestimulation/flowback period. This is attributed to degassing of naturally occurring methane after purgingduring groundwater sampling events.

n The BTEX compound toluene was detected in shallow rock groundwater (ranging from 6 to 72 µg/L).There was no detection of benzene, ethyl benzene or xylenes within shallow groundwater systems.

n Phenol and phenolic compounds have also been detected in the groundwater within the shallow rockand are considered to be natural occurring within coal measures.

n No distinctive trends in water quality were identified at groundwater monitoring sites that were attributedto pilot well activities.

Surface water levels

n Water levels at stream gauge sites WKSW01 (Avon River upstream), WKSW02 (Waukivory Creekupstream) and WKSW03 (Avon River downstream) reduced between September 2014 and early - midDecember 2014 due to the very low rainfall over this time period. Water levels are close to the zerogauge height at each site, and represent ponded water.

n Available water level data at the stream gauge sites do not show a response attributable to fracturestimulation or the initial flowback phase in late October – December 2014.

Surface water quality

n The streams are characterised as fresh and of neutral to slightly alkaline pH.

n EC, pH, major ions, dissolved metals, nutrients and dissolved gases showed no anomalous trendsduring the baseline and flow back periods. Identified trends in concentrations were attributed to naturalvariability over time, particularly the period of low rainfall and evaporative concentration over the lastmonths of 2014. Baseline boron concentrations in surface water range from <0.05 – 0.12 mg/L. Duringthe fracture stimulation period, surface water boron concentrations peak at WKSW01 on 19 November2014 (0.32 mg/L). This peak is not attributed to fracture stimulation activities as WKSW01 is locatedupstream of the Project on the Avon River. Concentrations of boron in surface water were belowlaboratory LoR during the commencement of the flowback phase.

n Total phosphorus is elevated above ANZECC guidelines for 80% and 95% protection of freshwateraquatic ecosystems. These elevated levels are attributed to agricultural activity in the area.

n Dissolved hydrocarbons including BTEX, PAH, Phenols and TPH were not detected in surface watersamples during baseline, fracture stimulation and initial flowback phases.

n No distinctive trends in water quality were identified at surface water monitoring sites that wereattributed to pilot well activities.

Fracture Stimulation fluid

n The fracture stimulation fluid contained no detectable BTEX, phenols and PAH.



Flowback Water

n The initial flowback water from the pilot wells is more saline (high total dissolved solids) and has greaterdissolved metal concentrations than the fracture stimulation fluid that was injected into the wells. Thisincrease in concentrations is due to mixing of fracture stimulation fluid with more saline deepgroundwater in the coal seams.

n Flowback water from WK12 and WK13 contained BTEX and other hydrocarbon compounds. TotalBTEX was detected at the following concentrations in samples from pilot wells: WK12 (47 µg/L on 29December 2014) and WK13 (70 µg/L on 16 December 2014 and 555 µg/L on 29 December 2014), andin the flowback tank (AST) (35 µg/L on 29 December 2014). Following receipt and review of theseresults, AGL voluntarily suspended the Project. BTEX compounds were not detected in the raw watersupply, nor in the fracture stimulation fluid. In addition, review of sampling and laboratory protocolspreclude contamination of samples with BTEX during sampling and analysis. The occurrence of BTEXcompounds in the flowback water is the subject of ongoing investigation by relevant regulators; howeveris considered to be naturally occurring and derived from the deeper coal seams.

Fracture stimulation additive concentrations during and post fracture stimulation

THPS

n TPHS was not detected in baseline groundwater or surface water monitoring.

n THPS was detected at three isolated locations during the fracture stimulation period. The detectionswere marginally above the LoR (50 μg/L), and within the margin of error of the LoR (50 μg/L ±50 μg/L).

n THPS was not detected in groundwater or surface water during the initial flowback phase.

Monoethanolamine Borate

n MEA was detected in baseline groundwater and surface water samples at concentrations ranging fromless than the LoR (1 μg/L) to 4 μg/L.

n MEA was detected in regional background groundwater and surface water samples at up to 10 km fromthe Project at concentrations ranging from less than the LoR to 19 μg/L. There is a negligible likelihoodthat MEA detected in these samples is associated with the fracture stimulation fluid given their distancesfrom the Project.

n DEA was detected in baseline and regional groundwater and surface water samples and is readilybiodegraded in the environment to MEA.

n Detections of MEA were recorded in groundwater samples collected on 12/13 November 2014. MEAwas not detected in the groundwater samples collected at the monitoring event on 17 Novemberimmediately after the 12/13 November 2014 (also during the fracture stimulation period) with theexception of WKMB01 which recorded an MEA concentration of 3 µg/L.

n All samples collected during the fracture stimulation period on 20 November 2014 from groundwaterclose to and distant from the pilot wells, and surface water both downstream and upstream of the wellsdetected MEA with concentrations ranging between 2 and 60 µg/L. MEA was not detected in thesamples collected at the monitoring event on 24 November immediately after the 20 November 2014(also during the fracture stimulation period).

n A review of sampling and laboratory protocols did not identify contamination of samples.

n The two highest concentrations of MEA in water samples were detected in the shallow rock atGW080487 (61 μg/L) on 13 November 2014, and at WKMB02 (60 µg/L) on 20 November 2014. Theconcentrations of all MEA detections (including the 60 μg/L (WKMB02) and 61 μg/L (GW080487)) arewithin the same order of magnitude of the highest regional background detections to date (19 μg/L).



n Where MEA was detected in surface water and groundwater, THPS concentrations were less than theLoR (50 μg/L ±50 μg/L) with the exception of WKMB03 on 12 November 2014 when the THPSconcentration was 57 μg/L which is considered within the margin of error of the LoR.

n MEA concentrations were below laboratory LoR in surface water and groundwater samples collectedduring the sampling event undertaken during the initial flowback phase.

n AGL has provided information to the relevant regulators on MEA detections.

n The source of MEA is currently unknown. The detection of MEA at measurable concentrations inbaseline samples and the regional background samples indicate that MEA is likely to originate from asource not related to the fracture stimulation fluid.

Isotope Studies of Water Origin and Age

n Deuterium versus Oxygen 18 results indicate the alluvial and shallow rock water is meteoric (originatingfrom atmosphere-rainfall) in origin as it lies on the Global Meteroric Water Line.

n Tritium analyses and radiocarbon dating indicate groundwater within the alluvium and surface water aremodern (< 50 years). Groundwater in the shallow rock is older, at between 2,300 to 7,100 years old.

n Carbon 13 and deuterium isotope results of dissolved methane of both surface and groundwaterindicate it is of thermogenic origin with exception of shallow rock bore WKMB06B in which the methaneis likely biogenic in origin. The results were comparable with methane isotope data for deep gas wellsand results for groundwater monitoring bores sampled during previous studies in Gloucester Basin.

Water Beneficial Use Conditions

There was no change in the water beneficial use category for alluvial and shallow bedrock water resourcesduring and after the pilot well fracture stimulation activities.

Actions to correct identified adverse trends

Analysis of monitoring results has not identified adverse trends that require corrective action.Notwithstanding, the following actions are being undertaken:

n Due to the baseline and regional detections of MEA, investigations into alternative fracture stimulationtriggers in surface water and groundwater samples have commenced and will be provided to therelevant regulators for consideration in advance of future pilot programs.

n The occurrence of BTEX compounds in the flowback water is the subject of ongoing investigation byrelevant regulators; however is considered to be naturally occurring and derived from the deeper coalseams. Corrective actions including enhanced monitoring have been proposed by AGL and arecurrently under review as part of the investigation by regulators. The suspension will remain in placeuntil this review is complete.



8. Statement of limitationsScope of services

This baseline and first operational quarter report (the report) has been prepared in accordance with thescope of services set out in the contract, or as otherwise agreed, between the client and ParsonsBrinckerhoff (scope of services). In some circumstances the scope of services may have been limited by arange of factors such as time, budget, access and/or site disturbance constraints.

Reliance on data

In preparing the report, Parsons Brinckerhoff has relied upon data, surveys, analyses, designs, plans andother information provided by the client and other individuals and organisations, most of which are referred toin the report (the data). Except as otherwise stated in the report, Parsons Brinckerhoff has not verified theaccuracy or completeness of the data. To the extent that the statements, opinions, facts, information,conclusions and/or recommendations in the report (conclusions) are based in whole or part on the data,those conclusions are contingent upon the accuracy and completeness of the data. Parsons Brinckerhoff willnot be liable in relation to incorrect conclusions should any data, information or condition be incorrect or havebeen concealed, withheld, misrepresented or otherwise not fully disclosed to Parsons Brinckerhoff.

Environmental conclusions

In accordance with the scope of services, Parsons Brinckerhoff has relied upon the data and has conductedenvironmental field monitoring and/or testing in the preparation of the report. The nature and extent ofmonitoring and/or testing conducted is described in the report.

On all sites, varying degrees of non-uniformity of the vertical and horizontal soil or groundwater conditionsare encountered. Hence no monitoring, common testing or sampling technique can eliminate the possibilitythat monitoring or testing results/samples are not totally representative of soil and/or water conditionsencountered. The conclusions are based upon the data and the environmental field monitoring and/or testingand are therefore merely indicative of the environmental condition of the site at the time of preparing thereport, including the presence or otherwise of contaminants or emissions.

Also, it should be recognised that site conditions, including the extent and concentration of contaminants,can change with time.

Within the limitations imposed by the scope of services, the monitoring, testing, sampling and preparation ofthis report have been undertaken and performed in a professional manner, in accordance with generallyaccepted practices and using a degree of skill and care ordinarily exercised by reputable environmentalconsultants under similar circumstances. No other warranty, expressed or implied, is made.

Report for benefit of client

The report has been prepared for the benefit of the client (and no other party). Parsons Brinckerhoffassumes no responsibility and will not be liable to any other person or organisation for or in relation to anymatter dealt with or conclusions expressed in the report, or for any loss or damage suffered by any otherperson or organisation arising from matters dealt with or conclusions expressed in the report (includingwithout limitation matters arising from any negligent act or omission of Parsons Brinckerhoff or for any loss ordamage suffered by any other party relying upon the matters dealt with or conclusions expressed in thereport). Parties other than the client should not rely upon the report or the accuracy or completeness of anyconclusions and should make their own enquiries and obtain independent advice in relation to such matters.

Other limitations

Parsons Brinckerhoff will not be liable to update or revise the report to take into account any events oremergent circumstances or facts occurring or becoming apparent after the date of the report.



9. Referencesn AECOM 2009, ‘Gloucester Gas Project Environmental Assessment - Volume 1’, Report No.

S70038_FNL_EA, dated 11 Nov 2009.

n AGL 2014a, Surface Water and Groundwater Management Plan for the Waukivory Pilot Project –Gloucester Gas Project.

n AGL 2014b, Water Portal. http://www.agl.com.au/waterportal

n AGL 2014c, AGL’s Gloucester gas exploration pilot approved, ASX and Media Releases, dated6 August 2014, http://www.agl.com.au/about-agl/media-centre/article-list/2014/august/agl-gloucester-gas-exploration-pilot-approved.

n ANZECC 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality Volumes 3and 4. Australian and New Zealand Environment Conservation Council & Agriculture and ResourceManagement Council of Australia and New Zealand, Canberra.

n AS/NZS 5667. Australia/New Zealand Standard. Water quality – sampling

n Bartos, TT & Ogle KM 2002, Water Quality and Environmental Isotopic Analyses of Ground-WaterSamples Collected from the Wasatch and Fort Union Formations in Areas of Coalbed MethaneDevelopment-Implications to Recharge and Ground-Water Flow, Eastern Powder River Basin,Wyoming, Water-Resources Investigations Report 02-4045, United States Geological Survey andUnited States Department of the Interior, Cheyenne, Wyoming, USA.

n Bureau of Meteorology (BoM) 2014, Climate Data Online, viewed January 2015,http://www.bom.gov.au/climate/data/.

n Clark, ID & Fritz, P 1997, Environmental isotopes in hydrogeology, CRC Press, pp. 328.

n Cosmetic Ingredient Review, 2012, On the Safety Assessment of Ethanolamine and Ethanolamine Saltsas Used in Cosmetics, Final Amended Report, March 27 2012.

n Crosbie, RS, Morrow, D, Cresswell, RG, Leaney FW, Lamontagne S & Lefournour M 2012, Newinsights into the chemical and isotopic composition of rainfall across Australia, CSIRO Water for aHealthy Country Flagship, Australia.

n Envirolab 2015. THPS uncertainty queries. Letter to Sean Daykin, Parsons Brinckerhoff (20/01/2015)

n Government of Alberta, 2010, Soil and Groundwater Remediation Guidelines for Monoethanolamineand Diethanolamine.

n HACH 2015, http://www.hach.com/DisinfectionSeries02.

n Hillis, RR, Meyer, JJ & Reynolds, SD 1998, ‘The Australian Stress Map’, Exploration Geophysics,vol. 29, pp. 420-427.

n Hunt, JW 1989, ‘Permian coals of eastern Australia: geological control of petrographic variation’,International Journal of Coal Geology, vol. 12, pp. 589-634.

n Lennox, M 2009, ‘Stroud Gloucester Trough: Review of the Geology and Coal Development’, AshleyResources, Sydney, dated January 2009.

n New South Wales Office of Water (NOW), 2012 Aquifer Interference Policy. Department of PrimaryIndustries.

n NHMRC 2011, ‘Australian Drinking Water Guidelines Paper 6 National Water Quality ManagementStrategy’, National Health and Medical Research Council, National Resource Management MinisterialCouncil, Commonwealth of Australia, Canberra.



n NSW Environment Protection Authority 2014, Licence – 20358, Licence variation notice number1525990, Draft.

n Parsons Brinckerhoff 2013a, ‘Hydrogeological Conceptual Model of the Gloucester Basin’, 2162406APR_7266 Rev_B, dated 28 June 2013, Parsons Brinckerhoff, Sydney.

n Parsons Brinckerhoff 2013b, ‘Hydrogeological investigation of a strike-slip fault in the NorthernGloucester Basin’, 2192406B PR_5741 RevC, dated August 2013, Parsons Brinckerhoff, Sydney.

n Parsons Brinckerhoff 2014a, (in preparation) ‘Numerical groundwater modelling of the Gloucester Basin- Local scale fault modelling’, 2193335A, Parsons Brinckerhoff, Sydney.

n Parsons Brinckerhoff 2014b, ‘2014 Groundwater and Surface Water Monitoring Status reportGloucester Gas Project- 2201007A-RES-RPT-001 Rev C, dated 20 November 2014, ParsonsBrinckerhoff, Sydney.

n Parsons Brinckerhoff 2014c, ‘Gloucester Gas Project - Tiedman Rainfall Sampling Memo’, 2201007A-RES-MEM-001 RevC, dated 1 October 2014, Parsons Brinckerhoff, Sydney.

n Parsons Brinckerhoff 2014d, ‘Drilling Completion Report: Waukivory groundwater monitoring bores -Gloucester Gas Project’, 2162406C-WAT-RPT-7761 RevB, dated 30 July 2014, Parsons Brinckerhoff,Sydney.

n Parsons Brinckerhoff (2014e) 2014 Hunter Groundwater and Surface Water Monitoring – Annual StatusReport, Hunter Gas Project, 2201003A-RES-RPT-001 RevD, dated November 2014.

n Parsons Brinckerhoff 2014f, ‘Draft - 2014 Flow Testing of Craven 06 Gas Well’, 2162406C-WAT-RPT-001 RevB, Parsons Brinckerhoff, dated December 2014 (draft).

n Peterman, Z. E., Hedge, C. E., & Tourtelot, H. A. (1970). Isotopic composition of strontium in seawaterthroughout Phanerozoic time. Geochimica et Cosmochimica Acta, 34, 104-120.

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