Regional groundwater chemistry zones: Queensland Murray ... · Regional groundwater chemistry zones of the Queensland Murray-Darling Basin – May 2018 i 1. Addendum to March 2017

Regional groundwater chemistry zones: Queensland Murray-Darling Basin

May 2018

Regional groundwater chemistry zones: Queensland Murray-Darling Basin - May 2018

Prepared by: Water Planning Ecology, Department of Environment and Science

© State of Queensland, 2018.

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Citation

McNeil, V.H., Raymond, M.A.A., Bennett, L., McGregor, G.B. and Southwell, B. 2018. Regional groundwater

chemistry zones: Queensland Murray-Darling Basin. Brisbane: Department of Environment and Science, Queensland

Government.

Acknowledgements

This report has been prepared by the Department of Environment and Science. The authors appreciated the technical

assistance and constructive ideas and comments from the following people Adrian McKay, Andrew Biggs, David

Thames, Marianna Joo, Elad Dafney and Kylie Davidson.

May 2018

http://creativecommons.org/licenses/by/3.0/au/deed.en

Regional groundwater chemistry zones of the Queensland Murray-Darling Basin – May 2018

i

1. Addendum to March 2017 report

1.1. Background

The draft Regional groundwater chemistry zones: Queensland Murray-Darling Basin report was released in

March 2017 for a three month public consultation period.

This report presented the results of a study to categorise the regional groundwater chemistry of the

Queensland section of the Murray-Darling Basin. It established local groundwater chemistry zones using

groundwater quality data. Draft groundwater water quality percentiles were developed for each chemistry

zone for regional consultation purposes.

Following the consultation period, the submissions received were considered and an update to the report

was required.

1.2. Description

The table below details the amendments that were made to this report following the consideration of

submissions.

Component Amendment Issue addressing

Figure 2-13 Maps have been updated to align with

Fitzroy and Burdekin groundwater layers.

Environmental values have been added to

each chemistry zone.

Figure 4

Alluvial zones

Addition of chemistry zone '13. Upper

Dumaresq'.

Chemistry zone '13. Upper Dumaresq'

was not displayed on Figure 4 despite

having water quality percentiles

presented for this zone in Table 3.

Addition of chemistry zone '14. Macintyre

Brook'.

Chemistry zone '14. Macintyre Brook'

was not displayed on Figure 4 despite

having water quality percentiles

presented for this zone in Table 3.

Figure 5

Fractured rock

zones

Chemistry zone '4. North Western Basalt

remnants' was subdivided into 'Eastern

Basement With Basalt Remnants' and

'Main Range Volcanics'.

'4. North Western Basalt remnants'

consists of scattered remnants on the

watershed, with no data. Subdividing

the zone allows alignment with

chemistry zones in the adjacent Fitzroy

and Burdekin basins.


remnants' replaced by '4. Eastern

This zone was previously split at the

QMDB-Fitzroy basin border despite the


ii


Basement With Basalt Remnants'. The zone

was merged with Fitzroy chemistry zone '3.

Eastern Basement With Basalt Remnants'.

water chemistry data indicating the zone

extends across both basins. Merging the

QMDB and Fitzroy zone allows the cross-

basin zone to be represented, and one

set of water quality objectives now

applies to this zone.

Addition of chemistry zone '5. Main Range

Volcanics'. The zone was merged with

Burdekin chemistry zone '7. Main Range

Volcanics'.

This zone was previously split at the

QMDB-Burdekin basin border despite

the water chemistry data indicating the

zone extends across both basins.

Merging the QMDB and Burdekin zone

allows the cross-basin zone to be

represented, and one set of water

quality objectives now applies to this

zone.

Table 3 - All

Aquifers

Update to water quality percentiles to

include additional groundwater data that

has been obtained since the initial analysis

in 2017.

Table 3 - Fractured rock aquifer


remnants' replaced by '4. Eastern

Basement With Basalt Remnants'. Update

to percentiles to include data from

adjacent zone in Fitzroy.

Merging of water quality data (collected

from east of Sandy Creek) for QMDB

zone '4. North Western Basalt remnants'

with Fitzroy zone '3. Eastern Basement

With Basalt Remnants' to allow

representation of the cross-basin

chemistry zone.

Addition of percentiles for chemistry zone

'5. Main Range Volcanics'.

Merging of water quality data (collected

from west of Sandy Creek) for QMDB

zone '4. North Western Basalt remnants'

with Burdekin zone '7. Main Range

Volcanics' to allow representation of the

cross-basin chemistry zone.

Table 3 - Mid

GAB aquifer

Update to percentiles for chemistry zone

'6. North Wallumbilla Bungil and Mooga'.

Merging of water quality data for QMDB

zone '6. North Wallumbilla Bungil and

Mooga' with Fitzroy zone '3. Bungil and

Mooga Outcrops' to allow


chemistry zone.


iii


Table 3 - Lower

GAB aquifer


'1. Central Surat Springbok Area' to include

data from adjacent zone in Fitzroy.


zone '1. Central Surat Springbok Area'

with Fitzroy zone '1. Central Surat

Springbok Area continued' to allow


chemistry zone.


'5. Northeastern Hutton Outcrop' to

include data from adjacent zone in Fitzroy.


zone '5. Northeastern Hutton Outcrop'

with Fitzroy zone '5. Northeastern

Hutton Outcrop continued' to allow


chemistry zone.


'6. Northern Hutton Outcrop' to include

data from adjacent zone in Fitzroy.


zone '6. Northern Hutton Outcrop' with

Fitzroy zone '9. Northern Hutton

Outcrop continued' to allow


chemistry zone.


'7. Northern Walloons' to include data from



zone '7. Northern Walloons' with Fitzroy

zone '4. Northern Walloons continued'

to allow representation of the cross-

basin chemistry zone.

Table 3 - Basal

GAB aquifer


'1. Precipice Outcrop' to include data from



zone '1. Precipice Outcrop' with Fitzroy

zone '3 Precipice Outcrop continued in

Upper Dawson' to allow representation

of the cross-basin chemistry zone.


'2. Eastern Central Area' to include data

from adjacent zone in Fitzroy.


zone '2. Eastern Central Area' with

Fitzroy zone '5 Eastern Central Area

continued' to allow representation of

the cross-basin chemistry zone.


'3. Northeastern Evergreen Outcrop' to

include data from adjacent zone in Fitzroy.


zone '3. Northeastern Evergreen

Outcrop' with Fitzroy zone '2 South

Eastern Evergreen Outcrop continued'

to allow representation of the cross-

basin chemistry zone.


iv


Table 3 - Earlier

sedimentary

basins

underlying the

GAB

Aquifer name change, from Basins

Underlying GAB.

To align with Fitzroy and Burdekin basin

aquifer name, as the aquifer is a cross-

basin aquifer.

Merging of data from chemistry zone '1.

Bowen Basin' with chemistry zone '2.

Upper Bowen Basin'.

To address a lack of data in each

individual zone.


'1. Bowen Basin' and '2. Upper Bowen

Basin' to include data from adjacent zone

in Fitzroy.


zone '1. Bowen Basin' and '2. Upper

Bowen Basin' with Fitzroy zone '8. Lower

Bowen continued' to allow


chemistry zone.


'3. Galilee Basin' to include data from



'3. Galilee Basin' with Fitzroy zone '2.

Southern Galilee Clematis' to allow


chemistry zone.


v

2. Glossary

Terms as used in this document

Al – Aluminium

Alkalinity – ability to neutralize acids to the

equivalence point of carbonate or bicarbonate

Alluvium – loose, friable material eroded and

reshaped by water

Anion – A negatively charged ion (e.g. Cl-).

Aquifer – underground water-bearing permeable

material from which groundwater can be

extracted

Artesian (confined) – groundwater at a lower

elevation than its recharge source, which is

confined under pressure by overlying impervious

beds. Water level will rise when a bore

penetrates the impervious layer. Aquifer may be

‘semi-confined’ if overlying material allows some

leakage.

B – Boron

Basalt – extrusive volcanic rock formed from

rapid cooling of lava

Baseflow – stream flow derived from deep

subsurface flow and delayed shallow subsurface

flow

Baseline quality – The most common water

quality across a zone, under present conditions

Bedrock – native consolidated rock underlying

the surface, usually overlain by weathered

material

Ca – Calcium ion (cation)

Cation – A positively charged ion (e.g. Na+).

Chemical type – chemistry of a groundwater,

characterised by particular ionic equivalence; the

major chemical types identified for QMDB

groundwater are:

1. Sodium bicarbonate

2. Sodium chloride

3. Lower sodium

4. Sulfate rich

5. Analogous to surface water

Ck – Creek

Cl – Chloride ion (anion)

CO3 – Carbonate

Cu – Copper

D/S – Downstream of

DO – Dissolved oxygen

EC – Electrical conductivity, a measure of salinity

measured in µS/cm

EH –Redox potential

Equivalence – amount of a substance which will

either – react with or supply one mole of

hydrogen ions (H+) in an acid–base reaction; or

react with or supply one mole of electrons in a

redox reaction

Evenly proportioned cations – water chemistry

where the major cations (Na, Ca and Mg) are in

roughly even proportions in terms of equivalents,

although in Queensland groundwaters sodium is

usually slightly in excess of each of the others.

F – Fluorine

Fe – Iron

GAB – Great Artesian Basin

GAB Cap – relatively impermeable rock layer

overlying the GAB

GDE – Groundwater dependant ecosystem

GDR – Great Dividing Range

GIS – Geographic information system

GMU – Groundwater management unit


vi

Granitic Rock – a rock formed from the molten

state at depth, where slow cooling gave it a

coarse granular texture. True granites have a

narrow range of chemical composition, but the

term is used broadly here to include all rocks of

similar appearance and origin.

Groundwater – water that is stored below the

plant root zone in soil pore spaces or in porous or

fractured rocks. The water table is the depth at

which all available space is saturated.

Group – Groundwaters with similar types of

chemistry.

GW – groundwater

GWDB – Groundwater database

Hardness – Hardness is a water quality parameter

caused primarily by calcium and magnesium ions

in solution. It is expressed as CaCO3 in mgl-1. Hard

water increases the amount of soap or detergent

required for washing, and also deposits mineral

scale or incrustation on kettles, boilers and

pumping equipment. Harder water can, however,

reduce the toxicity to the ecosystem of certain

trace substances. In terms of guidelines, ANZECC

and ARMCANZ (2000) advise that <60 is possibly

corrosive, 60–200 can be considered good

quality, 200–500 requires softening with an

increasing likelihood of scale, and >500 can cause

severe scaling.

HCO3. – Bicarbonate ion (anion)

Ion – An atom or molecule which has either an

excess or shortage of electrons, giving it a

negative charge (anion) or positive charge

(cation) respectively. Dissolved salts are generally

in ionic form, with cations being metallic (i.e. Na,

Ca, Mg) and anions non-metallic (i.e. Cl, SO4,

HCO3).

K – Potassium

Metamorphic – rocks where minerals and

structure have been altered after emplacement,

due to the heat and pressure exerted by deep

burial or earth movements.

Mg – Magnesium ion (cation)

Mn – Manganese

Na – Sodium ion (cation)

NaCl – Sodium chloride

NO3 – Nitrate

NTU – Nephelometric turbidity units

pH – measure of how acidic or alkaline a water is

by the concentration free hydrogen ions in

solution. The pH scale ranges from 0 to 14, with a

pH of 7 being neutral, values lower than 7 being

acidic, and pH values higher than 7 being alkaline

(basic). For instance, approximate pH values are

orange juice 3, coffee 5, rainwater 6, freshly

distilled water 7, seawater 8, and a baking soda

solution 9 (Decelles 2002).

PO4 – Ortho-phosphate

R – River

RAH – Residual alkali hazard

Recharge – hydrologic process where water

moves downward from surface water to

groundwater

Salinity – the dissolved salt content in water. In

most Queensland natural waters this includes the

cations Na, Ca Mg, and to a lesser extent K, and

the anions Cl and HCO3, with usually smaller

amounts of SO4 and NO3. These are known as the

major ions. Salinity can be measured in several

ways, although these are not exactly comparable:

Total Dissolved Ions (TDI) is a measure of the

major ions in solution expressed in mg/L. This is

most needed by catchment managers because it

can be used to measure mass transport of salts.

An alternative measure is Electrical Conductivity

(EC) which is the ability of the solution to conduct

an electric current in mS/cm. Although EC is

influenced by the type as well as quantity of salts,

as well as by factors such as temperature,

pressure and suspended matter, it is often used

as a substitute for TDI because it is easily


vii

measured. Salinity categories in this document

are based on median EC in µS/cm:

EC <200 very low

EC <200–500 low

EC <500–1,500 moderate

EC <1,500–5,000 high

EC >5,000 very high

Salinity is classified variable if the range is

more than twice the median.

SAR – Sodium adsorption ratio is used to measure

the dominance of sodium (Na) in the water

chemistry, and to determine whether Na levels in

irrigation water will cause soil structure to

deteriorate.

SiO2 – Silicon dioxide (or silica)

SO4. – Sulfate ion (anion)

Sodic – waters where sodium dominates the

cations in terms of proportion.

Surface water – water collecting on the ground or

in a stream, river, lake, wetland, or ocean

SW – Surface water

SWDB – Surface water database

SYSTAT – Statistical and graphical software

TDI – Total dissolved ions

TDS – Total dissolved solids

U/S – Upstream of

UA – Unincorporated (groundwater) areas

Water table – the surface where the groundwater

pressure head equals atmospheric pressure

Zn – Zinc

Zone – Geographically delineated area that is

likely to contain groundwater of a particular type

at one or more individual depth classes


viii

Contents

1. Addendum to March 2017 report ............................................................................................. i

1.1. Background i

1.2. Description i

2. Glossary ................................................................................................................................... v

Contents ..................................................................................................................................... viii

List of tables ................................................................................................................................. ix

List of figures ............................................................................................................................... ix

3. Executive summary ................................................................................................................. 1

4. Introduction ............................................................................................................................. 2

4.1. Approach and objectives 2

4.2. Regional setting 2

5. Data and methods ................................................................................................................... 7

6. Environmental values ............................................................................................................. 9

7. Regional groundwater chemistry zones .............................................................................. 11

8. Regional groundwater quality .............................................................................................. 22

8.1. Border Rivers 23

8.2. Moonie basin 23

8.3. Condamine 24

8.4. Balonne–Culgoa 24

8.5. Western streams 26

9. References ............................................................................................................................. 26

10. Tabulated results ................................................................................................................... 29


ix

List of tables

Table 1 QMDB groundwater chemistry zone aquifer system descriptions ..................................... 11

Table 2 Detailed description of water chemistry in each nominated groundwater zone of the QMDB ........................................................................................................................................... 30

Table 3 Statistical summaries of water chemistry within each nominated QMDB groundwater zone .............................................................................................................................................. 47

List of figures

Figure 1 River catchments in the QMDB region, and the structures which define GAB sub-basins . 3

Figure 2 Surface geology ................................................................................................................ 6

Figure 3 Distribution of bores with water chemistry across the QMDB ............................................ 8

Figure 4 Environmental values icons and definitions under EPP Water ........................................ 10

Figure 5 Alluvial zones .................................................................................................................. 13

Figure 6 Fractured rock zones ...................................................................................................... 14

Figure 7 Sediments overlying the GAB ......................................................................................... 15

Figure 8 Upper GAB zones ........................................................................................................... 16

Figure 9 GAB main aquitard zones ............................................................................................... 17

Figure 10 GAB mid aquifer zones ................................................................................................. 18

Figure 11 Lower GAB zones ......................................................................................................... 19

Figure 12 Basal GAB zones .......................................................................................................... 20

Figure 13 Earlier basins partially underlying the GAB ................................................................... 21


1

3. Executive summary

The Environmental Protection (Water) Policy 2009 (EPP Water), subordinate legislation to the

Environmental Protection Act 1994 (Qld.), establishes Healthy Waters Management Plans (HWMPs) as a key

planning mechanism to improve the quality of Queensland waters.

Healthy Waters Management Plans have been developed for the Condamine, Maranoa-Balonne,

Queensland Border Rivers-Moonie, and Warrego-Paroo-Bulloo-Nebine basins. With the exception of the

Bulloo drainage basin, these catchments are all part of the Queensland Murray-Darling Basin. The Bulloo

drainage basin is an internally draining system located between the Queensland Lake Eyre and Murray-

Darling Basins.

The Environmental Protection (Water) Policy 2009 provides the structure for establishing Healthy Waters

Management Plans and the features contained within them: including environmental values and water

quality objectives. Environmental values are the qualities that make water suitable for supporting aquatic

ecosystems and human uses. Water quality objectives are long-term goals for water quality management.

They are measurements, levels or narrative statements of particular indicators of water quality that protect

environmental values. Under the Environmental Protection (Water) Policy 2009, environmental values and

water quality objectives inform statutory and non-statutory water quality management planning and

decision-making.

The economic and social impacts of protecting Environmental values are considered through consultation.

At the completion of consultation and consideration of all submissions, finalised environmental values and

water quality objectives are subsequently recommended for inclusion under Schedule 1 of the

Environmental Protection (Water) Policy 2009.

Water quality objectives are produced for both surface waters and groundwaters. The development of

water quality objectives is informed by technical reports. This technical report supports the development of

water quality objectives for the groundwaters within Queensland Murray-Darling Basin and Bulloo

catchments. This report summarises and presents the results of locally derived water quality ranges for

groundwater chemistry zones across the Queensland Murray-Darling Basin and Bulloo catchments. The

water quality ranges were determined from data collected mostly since the 1960s and stored in the

Department of Natural Resources, Mines and Energy groundwater database. Within each chemistry zone

defined in this report, groundwater quality is assessed for artesian waters and selected depth ranges for

sub-artesian waters.

This summary report is intended to support consultation on Healthy Waters Management Plans developed

for Queensland Murray–Darling Basin and Bulloo catchments, and to present draft environmental values

and water quality objectives for the groundwaters of Queensland Murray-Darling Basin.


2

4. Introduction

This report presents the results of a study to categorise the regional groundwater chemistry of the

Queensland section of the Murray-Darling Basin (QMDB). It establishes consistent local chemical ranges for

regional consultation purposes.

4.1. Approach and objectives

Salinity related water quality problems, including the composition of individual salts, can seriously affect

agricultural production, the viability of infrastructure, the health of aquatic and terrestrial ecosystems, and

the welfare of regional communities. Within Queensland, groundwater is a major and increasingly

significant resource, particularly in rural areas, and supports a range of groundwater dependent

ecosystems. Despite its importance, there is limited knowledge and understanding of the groundwater

systems over wide areas of Queensland, both because of the size of the state, and because of its low but

increasing population density.

Comparatively homogeneous water chemistry zones have previously been defined for Queensland’s

surface waters so that baseline ranges could be determined for surface water salinity and water quality

parameters. However, the chemical zonation of groundwater is a more complex task because sources and

flow paths are less clear, spatial variation is three dimensional, and the chemistry is influenced by many

factors. Some natural factors include recharge composition, soils, geology and rainfall. Other, more

localised influences are related to human activities and interactions between water bodies. The resulting

high natural variability of groundwater chemistry may breach guidelines for environmental values

pertaining to surface water, even in the absence of human impacts. The aim of this project is to define

groundwater zones for the QMDB, and to calculate the background ranges of water quality constituents

within them as an aid to establishing appropriate groundwater quality guidelines. The calculated ranges

exclude outliers caused by either local contamination or small, uncharacteristic aquifers, but it is not

currently feasible to account for any general changes that may have occurred prior to monitoring.

4.2. Regional setting

The Murray-Darling Basin is Australia’s most significant river system, and drains parts of Queensland, New

South Wales, Victoria, South Australia, and the Australian Capital Territory. The QMDB (Figure 1) covers

about 25 percent of the total MDB area. It extends about 800 km east to west and up to 500 km north

south, with an area of 260,791 km2 and has a population of approximately 221,500 people. The QMDB

comprises the Border Rivers, Moonie, Condamine and Balonne, Nebine, Warrego, and Paroo drainage

basins. The internally draining Bulloo catchment is located between the Queensland Lake Eyre and Murray-

Darling Basins, but is included for state planning purposes. The Bulloo River terminates south of the

Queensland border in an expansive area of floodplain and wetlands, but because of the low relief and arid

climate it has little external discharge except during exceptional flood events, particularly in the south.

Annual rainfall decreases markedly across the QMDB from over 1,000 mm on the eastern margin, to <300

mm towards the south western corner. Precipitation is summer dominant and very variable, with 60 to 65

per cent received between October and March. Mean average evaporation exceeds rainfall for every

month of the year, and drought is a recurring feature. As a consequence of the climate variability,

groundwater recharge is strongly episodic and relies on periods of unusually high rainfall or wetter than

average winters to increase deep drainage rates. The landscape consists in the most part of plains or gently


3

undulating terrain, bounded to the north, east and southeast by hills and steep plateaus which rise 1,400 m

along the Great Dividing Range (GDR) in the south-east.

Figure 1 River catchments in the QMDB region, and the structures which define GAB sub-basins

Although climate and local hydrology are also important, the varied and complex geology of the QMDB, as

described in Kingham (1998); Day (1983) and Radke et al. (2012) has a major influence on groundwater

quality (Figure 2). The oldest rocks in the QMDB were formed about 600 million years ago, around the start

of the Palaeozoic Era, which lasted till 250 million years ago. During this period, marine sediments and

volcanic debris built up in the east, an area which was then offshore. These sediments were subsequently

folded, faulted, metamorphosed, and intruded by granites, before being raised above sea level, where their

roots now form the GDR. They are exposed within the QMDB on the western side of the upper Condamine

alluvial valley, the Border River catchments of Dumaresq River and Macintyre Brook, and in the most

northerly headwaters of the Warrego and Maranoa Rivers. Groundwaters associated with Palaeozoic

terrains tend to be moderately saline (500–1,500 µS/cm as defined in Table 2 below) and hard, with evenly

proportioned cations except for a slight preponderance of sodium. In granitic Palaeozoic terrains, as in the

Border Rivers, the groundwater tends to be fresher and more sodic.

By the middle of the Palaeozoic, the area to the west of the GDR had stabilised, and begun to sag into

basement depressions such as the Galilee and Cooper Basins into which mainly freshwater sediments

including coal were deposited. This phase continued till the early Mesozoic (about 200 million years ago),

when uplift caused these basins to be eroded to a relatively even surface.

The period of erosion was brought to an end later in the Mesozoic, when the eroded surface began to sink

into a new series of depressions overlying the earlier basins. Permeable quartzose sandstones were


4

deposited in these new depressions, alternating with relatively impermeable confining beds of mudstone

and siltstone. These sediments formed the Great Artesian Basin (GAB) aquifer system. The Queensland

section of the GAB consists of two major sub-basins divided by the older Nebine Ridge west of the Balonne

River (Figure.1). The Surat Basin lies to the east of the ridge, and the Eromanga Basin to the west. A minor

sub-basin, the Cecil Plains section of the Clarence–Moreton Basin, underlies the upper Condamine

catchment and is separated from the Surat Basin by the Kumbarilla Ridge which passes from North to South

between Dalby and Chinchilla.

Then around about 110 million years ago, the GAB area including the dividing ridges, were inundated by a

shallow sea. By the time it withdrew, which was towards the end of the Mesozoic (about 90 million years

ago), it had deposited a fine, silty, almost impermeable marine layer over the earlier freshwater sediments,

including the GAB aquifer system and dividing ridges. This overlying marine layer is known as the GAB Cap.

The uppermost unit of the marine layer in the GAB is the Griman Creek Formation which underlies the

lower Weir and Macintyre flood plains and outcrops to the north of the alluvial boundary. Although the

Cecil Plains sub-basin was linked to the Surat by a narrow strait throughout the formation of the GAB and

its subsequent marine inundation, the GAB Cap has been completely eroded from this sub-basin to expose

the underlying freshwater sediments. These are represented by the Walloon Coal Measures and Marburg

Sandstones which underlie the flood plains in the upper Condamine and Oakey Creek catchment. They

outcrop along the edges of the alluvium, and contain stored salt and have the potential to contaminate

adjoining alluvial aquifers through seepages of saline groundwater.

After the retreat of the inland sea towards the end of the Mesozoic, the newly exposed surface of

southwest Queensland was subject to erosion and intense chemical weathering, in places to over 100 m

depth. Tertiary freshwater sediments such as the Glendower Formation and Chinchilla Sands being

deposited over the GAB Cap were also subjected to these weathering regimes. Silica was leached from the

surficial horizons, leaving clay with iron stained bands. The dissolved silica was flushed lower in the soil

profile as a gel, where it solidified into rocky layers and masses known as silcrete. Removal of overlying

material by subsequent erosion exposes the silcrete, resulting in a hard, stony surface referred to as

duricrust which is still evident over much of the flat topped uplands.

The GDR was uplifted around 65 to 32 million years ago, tilting the GAB to the southwest and creating

artesian pressures in the aquifers. As a result, springs broke out along structures such as fault lines, thin

confining beds, or other obstructions to flow. The uplift also brought about the extensive basaltic eruptions

which occurred over the last 20 to 2 million years. Lava flows were widespread over the emerging range, as

well as on some of the northeast and eastern sedimentary headwaters, but are now largely dissected,

leaving remnants as volcanic necks or basalt capped mesas. The basalt itself is pervious in many areas, and

produces groundwater which is unusually high in magnesium. Many of the previous surface exposures of

GAB aquifers are still covered by basalt, despite subsequent erosion, and this limits current recharge to the

relatively small intake areas along the western slopes of the Range or infiltration from QMDB surface

waters, either directly to the aquifers or through more recent intervening beds. Surface water streams with

possible recharge potential have been identified as the upper Maranoa, the middle reaches of the Weir,

and, to a lesser extent, the upper Warrego. The GAB aquifers typically yield sodium bicarbonate

groundwaters of moderate salinity. The QMDB subsided and took shape during the Cenozoic (the Era that

began at the end of the Mesozoic, about 65 million years ago, continuing to the present). When the GDR

initially formed at the beginning of this time, the divide between coastward and inland draining catchments

was further to the east. Larger catchments extending into wetter areas provided great erosive power to the

ancestral river systems within the QMDB, allowing them to form deep and extensive flood plains which

incised up to 200 m into the weathered GAB Cap. However, rainfall was always higher in the east, and the


5

catchments steeper, so that over time, the coastal streams were able to out compete those draining inland,

capturing their headwaters and moving the divide further west. In addition, a drying climate over the last

12 million years has further reduced stream discharge. This has left the original floodplains, often referred

to as Cenozoic alluvium, covering much larger areas than are presently active. Weathering has greatly

reduced their permeability, and although both the Cenozoic alluvium and the GAB Cap may contain limited

supplies of groundwater it is usually saline (1,500–5,000 µS/cm as defined in Table 2) and high in sodium

chloride. The upper reaches of the current stream channels are often deeply incised into the surrounding

Cenozoic systems, developing small recent floodplains around them. These recent alluvials usually yield

good quality groundwaters which may be relatively hard in terms of usage guidelines, but limited recharge

increases their vulnerability to hydrological stress, with consequent risk of contamination from saline

seepages issuing from adjacent older deposits.

The most extensive floodplains are in the Condamine catchment, the lower McIntyre–Weir river system

along the Queensland–NSW border, in the lower Balonne–Maranoa–Culgoa and Moonie catchments, and

associated with the Warrego and Paroo Rivers in the far west. Floodplains in the Condamine, Border Rivers,

Moonie and Balonne catchments are utilised for both dry land and irrigated cropping. Elsewhere grazing is

the main rural industry, with mining also significant.

Towards the west, the lower reaches of the streams have evolved into a mosaic of active and inactive

alluvial fans, with braided channels resting on the extensively weathered GAB cap. The catchments in this

region are separated by low dissected plateaux, capped by duricrust remnants. Sand plains have been

formed by wind action, with some dune development on the edges of high ground, particularly along the

western regions and the Moonie River. Some of these may contain small local groundwater systems.


6

Figure 2 Surface geology


7

5. Data and methods

Much of the current groundwater chemistry data of the QMDB is stored in the databases of the

Queensland Department of Natural Resources and Mines (DNRM) which, although extensive, was unevenly

collected in space and time. There are more than 7700 sub-artesian and 4200 artesian water quality

samples, supplemented by over 2500 groundwater level measurements from around 6600 bores, mostly

since the mid-1960s.

This project has employed both statistical and conceptual methods to define zones of similar groundwater

chemistry within the region (after Raymond and McNeil 2011, and Raymond and McNeil 2013). In

summary, the groundwaters of the QMDB were divided into aquifer types; three subartesian types to

represent alluvial and fractured rock systems, and the deposits overlying the GAB. Five GAB layers were

required to represent the GAB underlying the QMDB, which is a complex of layered and interfingering

aquifers and aquitards. There were broadly grouped on the divisions used by Smerdon et al. (2012), but

with the bottom sequence divided into ‘lower’ and ‘basal’ layers to reduce inhomogeneity. A layer was also

defined for the basins underlying the GAB, in this case the Bowen and Galillee.

All available surface and groundwater water data were then combined, and areas of similarity defined

through a clustering procedure based on major ions which is described in McNeil et al. (2005). The surface

water was included so that comparable chemistry could be used as an indicator of possible interaction. Five

major chemical types were identified, these being:

1. Sodium bicarbonate Typical of many GAB waters

2. Sodium chloride High salinity and probably related to poor recharge

3. Lower sodium Characteristic of basalts and Palaeozoic sediments

4. Sulphate rich Probably associated with soil profiles containing gypsum

5. Surface water type Fresh, high in bicarbonate, mixed cations, near surface

These water types were plotted and used in conjunction with the lithology to define groundwater zones for

each aquifer type or layer, with each map showing significant spatial variation.

Current baseline water quality was then estimated for each zone, represented by percentiles of each

parameter recorded in the GWDB. The zones are described in Table 2, and their water quality percentile

ranges are given in Table 3. Some of the more extensive alluvial zones, as well as some overlying the GAB,

show substantial water quality variation close to the stream. This is expected given the proximity to

recharge, so the zones concerned are provided with percentiles for a 1.5 km buffered area around the

stream as well as for the zone as a whole.

This study acknowledges that the zones and their baseline ranges only represent current mid-range levels,

chiefly because data is limited particularly for the pre-European period; however, it is emphasised that

these interim values are in line with the precautionary principle in providing a filter to identify outlying sites

and sudden or rapid change. In areas of high priority, groundwater models or other more intensive

assessment methods can be applied at a later date with the support of ongoing data collection. This would

allow the ranges to be refined, natural processes to be differentiated and anomalies due to atypical local

aquifers to be identified.


8

Figure 3 Distribution of bores with water chemistry across the QMDB


9

6. Environmental values

The draft social, economic, cultural and environmental values and uses of water across QMDB drainage basins were established through the environmental values framework under the EPP Water. Environmental values are the qualities of water that make it suitable for supporting aquatic ecosystems and identified human uses. Setting environmental values through community and stakeholder consultation reflects how a local region values and uses water. Under the EPP Water, and as depicted by Figure 4, environmental values include:

aquatic ecosystem

agriculture (including irrigation, stock and domestic)

aquaculture

human consumption of aquatic foods

drinking water (suitable for treatment before supply as drinking water)

industrial use

recreation (primary, secondary and visual/aesthetic), and

cultural and spiritual values (modified to ‘cultural, spiritual and ceremonial values’ at the request of local Traditional Owners).

To enable the accurate and comprehensive depiction of environmental values that apply to each groundwater chemistry zone, environmental values for groundwaters were determined through a three-step process.

1. Bore installation records, which are held within the Queensland Government Water Entitlements Registration Database, were used as a starting point to list how the groundwater in each bore is used and valued.

2. Consultation on the preliminary groundwater environmental values from step 1 occurred with technical experts from the Department of Natural Resources, Mines and Energy, NRM bodies of the QMDB region, and community, environment and industry groups, to ensure the approach taken to identify groundwater EVs is accurate and representative.

3. Groundwater environmental values were amended to reflect feedback during step 2. See Figures 5–13 for the environmental values that have been identified for groundwaters of the QMDB.


10

Figure 4 Environmental values icons and definitions under EPP Water

Aquatic ecosystem

• The intrinsic value of aquatic ecosystems, habitat and wildlife in waterways, waterholes and riparian areas, for example, biodiversity, ecological interactions, plants, animals, key species (such as turtles, yellowbelly, cod and yabbies) and their habitat, food and drinking water.

Irrigation

• Suitability of water supply for irrigation, for example, irrigation of crops, pastures, parks, gardens and recreational areas.

Farm water supply/use

• Suitability of domestic farm water supply, other than drinking water. For example, water used for laundry and produce preparation.

Stock watering

• Suitability of water supply for production of healthy livestock.

Aquaculture

• Health of aquaculture species and humans consuming aquatic foods (such as fish and prawns) from commercial ventures.

Visual recreation

• Amenity of waterways for recreation which does not involve contact with water. For example, walking and picnicking adjacent to a waterway.

Human consumers of aquatic foods

• Health of humans consuming aquatic foods, such as fish and prawns, from natural waterways.

Primary recreation

• Health of humans during recreation which involves direct contact and a high probability of water being swallowed, for example, swimming, diving and water-skiing..

Secondary recreation

• Health of humans during recreation which involves indirect contact and a low probability of water being swallowed, for example, wading, boating, rowing and fishing.

Drinking water supply

• Suitability of raw drinking water supply. This assumes minimal treatment of water is required, for example, coarse screening and/or disinfection.

Industrial use

• Suitability of water supply for industrial use, for example, food, beverage, paper, petroleum and power industries, mining and minerals refining/processing. Industries usually treat water supplies to meet their needs.

Cultural, spiritual and ceremonial values

• Cultural, spiritual and ceremonial values of water means its aesthetic, historical, scientific, social or other significance, to the past, present or future generations.


11

7. Regional groundwater chemistry zones

Regional groundwater chemistry zones were established across nine aquifer systems (Table 1, Figures 5–

13). For each aquifer system, zones with homogeneous water chemistry have been defined and ranges for

major ions, pH, and electrical conductivity calculated where sufficient data was available (Table 2 and 3).

Table 1 QMDB groundwater chemistry zone aquifer system descriptions

Aquifer system Description Figure

reference

Alluvia Recent alluvium divided into 22 zones based on water quality and factors

such as extent of alluvium, and sub-catchment characteristics. Water

quality is moderate to saline NaCl or NaHCO3, generally hard with a

tendency to scale. Northeast is richer in Ca and Mg due to basalts and

other weatherable terrains. Data sufficiency very variable, with best in the

Condamine region.

Figure 5

Fractured rock Aquifers in hard rock with water stored in fractures. Divided into eight

zones on the basis of rock type, location and water quality, with four in

basalt and four in granite or trap rock. Water quality in the basalts is

moderately saline Mg then Na, with HCO3 then Cl, hard with some

scaling, based on reasonable amounts of data. There is little data for the

other zones, but the water quality appears to be Na then Ca Cl, of

moderate to high salinity, with recordings of high fluoride in the New

England Granites and occurrences of acidic groundwater in the Texas

Beds.

Figure 6

Sediments

overlying the

GAB

The overlying sediments consist of Tertiary sediments (Glendower Fm),

weathered Cainozoic alluvium surrounding and underlying recent

alluvium, and sand dunes in the southwest corner of the region. Based on

few data, the water quality is moderate to highly saline NaCl, with lower

salinity and higher HCO3 near streams. High fluoride has been recorded in

the Glendower Fm, but no data is available for the sand dunes.

Figure 7

Upper GAB The Upper GAB comprises the top beds of the Rolling downs Group,

namely the non-flowing Winton and Mackunda aquifers with

contemporaneous Upper Cretaceous clayey deposits. It corresponds to

the Gabora Winto Mackunda Groundwater Unit, with additional upper

Creataceous material but without the Allaru Mudstone aquitard. The

Upper GAB is divided into five zones, based on lithology and location.

There is little data, but the water quality appears to be mostly NaCl of

variable but often high salinity.

Figure 8

Main GAB

aquitard

This is the lower layers of the Rolling Downs Group which form the main

confining layer of the GAB. Mainly Wallumbilla Fm, with Allaru and

Toolebuc in the northwest, Coreena aquifer in the central region,

Doncaster in the northeast and Griman Creek in the southeast. It

corresponds to the Gabora Rolling Downs and Normanton Units. The

salinity is spatially variable, and this with the lithology is used to define

nine zones, Although data is scarce, the prevailing chemistry is moderate

to highly saline NaCl groundwater, with salinity lower to the north and

west. Occasional high fluoride levels occur, mainly in the Wallumbillas.

Figure 9

Mid GAB

aquifers

This represents the main confined GAB aquifers, particularly the

Hooray/Cadna-owie systems to the west, mostly within the Eromanga

Figure 10


12

Basin, and the eastern (Surat) equivalents including the Bungil, Mooga,

Orallo, and Gubberamunda, with the Kumbarilla in the east. It

corresponds to the Gabora Hooray in the west and Cadna-owie and

Mooga in the east. Water quality is complex and variable, particularly

around the outcrops in the north and east, and this, with the lithology is

used to define 14 zones. Data sufficiency is poor, but the water quality

appears to be moderately saline Na HCO3, over most of the west and

southern central area, but more variable around the north and eastern

outcrops, with saline NaCl to the east, mainly around outcrops and thicker

sequences of Bungil and Mooga, or sometimes associated with the

Gubberamunda and Kumbarilla. High fluoride levels may also occur in the

southeast, away from the outcrop areas.

Lower GAB This is a thick sequence of important aquifers and aquitards, including the

Adori in the north west, Hutton, mostly in the west, Springbok in the

central Surat and Boxvale aquifers, and the Injune Creek, Westbourne

and Walloon aquitards. It corresponds to the Gabora Hutton and

Springbok Walloon Units, except for the Evergreen Fm, and a number of

other formations located mainly in the Clarence Morton Basin. These were

transferred to the Basal GAB to avoid excessive complexity in this

division. Twelve zones were defined on the basis of water quality and

lithology. Although data sufficiency is poor for most zones, it appears that

most of the west and central area, away from the outcrops, has a fairly

uniform, moderately saline NaHCO3 water type. However, the outcrop

areas in the north and east are much more variable, with those on the

eastern edge are mostly high salinity NaCl, probably influenced by

underlying or overlying Walloons.

Figure 11

Basal GAB This division represents the lowest beds in the GAB, mainly the Evergreen

aquitard and underlying Precipice Sandstone. It also includes members of

the Bundamba Group in the Clarence Moreton Basin. The Gabora

equivalents are the Precipice Unit, and the Evergreen Fm. from the Hutton

Unit. The division is absent from the southwest of the QMDB. Six zones

have been defined, based on lithology and limited water quality data. The

groundwater is generally moderately saline, dominated by HCO3 with

either Na, or mixed cations in northern outcrop area near basaltic

remnants. Instances of high fluoride have been recorded in the central

Surat area.

Figure 12

Earlier basins

partially

underlying the

GAB

These Permian-Triassic basins represent hydrological networks that pre-

date the GAB and were eroded before GAB sedimentation commenced.

The QMDB includes the Bowen Basin underlying the Surat, and the

Galilee underlying the northern part of the Eromanga. The corresponding

Gabora unit is the Clematis. Three units are identified on the basis of

location and hydrological unit, but only the Bowen Basin Zone has water

quality data, probably because of depth considerations. The available

data indicates Na HCO3 groundwater of relatively high salinity, with high

fluoride occurrences.

Figure 13


13

Figure 5 Alluvial zones


14

Figure 6 Fractured rock zones


15

Figure 7 Sediments overlying the GAB


16

Figure 8 Upper GAB zones


17

Figure 9 GAB main aquitard zones


18

Figure 10 GAB mid aquifer zones


19

Figure 11 Lower GAB zones


20

Figure 12 Basal GAB zones


21

Figure 13 Earlier basins partially underlying the GAB


22

8. Regional groundwater quality

While the groundwater chemistry in the QMDB groundwater is complex, some distinct patterns have

emerged. Salinity was found to be generally moderate, but with notable occurrences of high to very highly

saline beds throughout the region. The chemistry of sub-artesian waters was relatively consistent with

depth across most zones, but with some notable exceptions, for instance Zone 20 Tinnenburra, a

fragmented area in the west of the region which is associated with recent and Cenozoic alluvials with some

GAB Cap. The chemistry of artesian bores becomes more varied west of the Balonne River subcatchment.

The major chemical types listed above were identified and used in defining groundwater zones as shown in

Figure 2. In the upland areas, including the upper Condamine and Border Rivers and extending into GAB

recharge zones, the available groundwater is relatively fresh but hard (Type 5), resembling local surface

water. This similarity to surface water suggests some interaction in these regions, and the hardness may be

sufficient to cause mineral scale on bore casings, screens or pumping equipment as observed in the

Toowoomba area (Anderson et al. 2010). Sodium bicarbonate (Type 1) is the most common chemical type,

including the vast majority of artesian and closely associated sub-artesian groundwaters which underlie

nearly the whole region. However, a significant proportion of the more saline and sodium chloride

dominated samples (Type 2) samples are from the GAB, particularly along the Kumbarilla Ridge as it crosses

the Condamine and Border Rivers and separates the Surat to the west from the Clarence–Moreton to the

East, and also near the Warrego and Maranoa Rivers in the central sections of their catchments, as well as

under the braided streams in the lower parts of the catchments between Nebine Ck. and the Paroo River.

The differences in chemistry probably result from which aquifer is being accessed. The presence or depths

of specific aquifers is, in turn, influenced by sub-surface features of the GAB structure (Esterle et al. 2013).

By contrast, there is a group of shallow GAB bores in the headwaters of the Maranoa and Warrego

catchments where the chemistry is relatively fresh and very variable. These fall close to or within the

Eastern Recharge section of the GAB, on the flanks of the GDR (Exon et al. 1966, Galloway 1974).

The other main groundwater type in the QMDB is usually associated with basaltic or volcanic geology. This

occurs mostly in the Condamine and upper Border Rivers catchments, but also sporadically over the GAB

cap areas, probably in association with residual basalt or GDR remnants. The characteristic chemistry here

is of moderate to very high salinity with relatively low levels of sodium. Another feature of the QMDB

groundwater chemistry is the unusually high sulfate levels which occur sporadically in deeper aquifers,

notably in the GAB Cap or other low porosity GAB beds. This could be related to inland acid sulfate soils, as

noted in MDB groundwaters downstream of Queensland, and also postulated for floodplains along the

NSW border where gypseous clays are associated with very saline groundwater within 30 m of the surface

(MDBA 2011).

There are a number of other potential water quality issues which may be significant within the area, but

which cannot be assessed at present because of limited data. In terms of nutrients, for instance, the

number of samples from the QMDB stored in the GWDB has averaged around 50–150 a year since about

1960, with more between the mid-1970s to mid-1990s. Sporadic detections of nitrate in excess of drinking

water guidelines occurred during this time around the Darling Downs, with levels of NO3 as N usually

exceeding 1 mg/L through the 1960s to early 1970s and 5–100 mg/L not being uncommon. However,

median levels of NO3 N declined after the 1970s, with recordings above 1 mg/L being rare since the 1990s.

Basaltic aquifers, common in the area, can be highly vulnerable to pollution because of the rapid transit of

water from the surface. Vulnerability is greater if there are overlying sources of contamination such as


23

feedlots, septic tanks or fertilizer applications are present. The apparent declining trend mirrors the stable

or declining trends in groundwater nitrate that were observed in the Bundaberg area when excess fertilizer

application was reduced (Biggs et al. 2000). This was assumed to be due to dilution and discharge to

streams through groundwater movement, denitrification processes in the aquifer or uptake of nitrate by

crops when irrigated by groundwater (Seitzinger et al. 2006).

The presence of other microorganisms in the groundwater is unknown, but the only species of

consequence are likely to be iron reducing bacteria (Biggs 2014). These can cause serious economic damage

through corrosion of bore casings, and are known to occur in the region (GHD, 2010). Reliable data are

scarce for pesticides and other problems such as trace metals. The levels of salinity and hardness within

both the ground and surface waters should favour rapid precipitation of toxic metals, and both the depth

to groundwater and the clay content of the soils would protect against pesticides. Stygofauna have also

been widely detected in the region at all levels of salinity, for instance in the Border Rivers (Schulz et al.

2013), but their significance cannot yet be assessed.

8.1. Border Rivers

The Border Rivers rise on the western slopes of the Great Dividing Range around the Queensland border,

and eventually flow into NSW via the Barwon River. The Queensland section includes the Weir River (Basin

4162) and its north-eastern tributaries of Dumaresq River (Basin 4163) and Macintyre Brook (Basin 4164).

These tributaries yield significant surface water resources as well mainly shallow groundwaters.

Groundwater is more relied on at the drier downstream end of the Weir catchment, with the majority of

bores in this area being deeper than 60 metres. Most were designated as artesian, although data for this

study was rare downstream of Goondiwindi.

Water chemistry is variable and complex, but similarities between surface and groundwater suggest some

interaction. The major surface type is a low salinity bicarbonate water which is slightly dominated by

sodium but also rich in calcium. This type is also important in aquifers shallower than about 30 m, and

extends in some places to depths below 60 metres. Another significant type in surface and shallower

groundwater is moderately saline, with bicarbonate as the major anion and evenly proportioned cations.

The water may be hard enough for mineral encrustation to reduce the efficiency of bores. Most artesian

bores, including virtually all those deeper than 100m, access typical moderately saline sodium bicarbonate

waters also encountered in some surface and shallow groundwaters. However, artesian bores upstream

along the Kumbarilla Ridge which passes under Inglewood may access highly saline sodium chloride

aquifers. Samples with this chemistry are also found occasionally in the surface and shallow groundwater

systems, becoming more prevalent with depth. They represent most of the groundwaters below 30 or 40 m

and merge with the artesian system upstream in the Weir catchment. This supports views that fresh

recharge is infiltrating from the middle reaches of the Weir River (Green et al. 2012, MDBC 2005).

8.2. Moonie basin

The Moonie (Basin 4172) is a moderate sized catchment located between the Border Rivers and the upper

Condamine. It discharges into the Barwon River over the NSW border. The water supplies in this basin are

not extensive, neither is the availability of data, but the climate is drier than that of the Condamine and the

Border Rivers, so that the mainly artesian groundwater is an important local resource with some bores

recorded as deep as 2,000 metres. There are some deeper subartesian waters which extend below 60 m,

and the water quality data available for them indicates a chemistry which appears to be transitional

between the Border Rivers and the more northern and western areas of the QMDB. The surface water is


24

low in salinity and dominated by bicarbonate, although the cations are evenly distributed rather than being

sodium dominated as is usual in the Border Rivers surface waters. Ground/surface interaction cannot be

commented on as there is no chemistry data for shallower groundwaters, but both the artesian and the

known subartesian aquifers mostly contain the moderately saline sodium bicarbonate chemistry which is

typical of the artesian systems of the region. However, saline to highly sodium chloride groundwaters are

occasionally found at depths of between 60 m and 110 m in the vicinity of the Kumbarilla Ridge as it crosses

the eastern corner of the catchment, and possibly other subsurface structures.

8.3. Condamine

The Condamine (Sub-basin 4223) contains one of the largest and most important subartesian aquifer

systems in the state, and is mainly groundwater dependent although there are also major surface water

resources. It is represented by a very large repository of both ground and surface water data which was

collected during prolonged and intensive water resource development since the 1960s. The mainly

subartesian groundwater of the Central Condamine Alluvium Groundwater Management Area covers the

entire regional depth range of over 100 m, but is mostly between 20-80 m with a median of 40 metres.

Several tributaries also have significant areas of productive alluvium, and basalt cappings over the

tablelands also yield substantial supplies of groundwater (Reid et al. 2009). The GAB Cap is generally

absent from the landscape, but the geology and hydrology are variable and complex and their effects on

water quality are possibly influenced by long-term usage patterns. There appear to be areas where ground

and surface water interact, and others where they remain essentially separated (Dafny and Silburn 2013),

and the groundwater chemistry shows trends in composition on the vertical and regional scale, suggesting

slow and limited intermixing (Braaten and Gates 2004).

Although the composition of the surface water is variable, the most common chemistry is a low salinity

bicarbonate type, widespread within the QMDB, which is slightly dominated by sodium, particularly during

base flows. This type does not occur in the groundwaters of the Condamine, unlike the other two

significant surface water types within the subcatchment which are important components of shallow to

moderate depth subartesian groundwaters. The first of these has the evenly proportioned cations

consistent with the Palaeozoic or basaltic geology of the headwaters, while the second is a moderately

saline sodium chloride type, relatively high in magnesium, which is probably related to the Cenozoic

alluvium or underlying Walloon Coal Measures. These two types form the bulk of the groundwater down to

about 30 m, although the proportion and salinity of the sodium/magnesium chloride type increases with

depth and is particularly common in very deep subartesian waters where flow is restricted. In some areas,

mostly below 60 m in depth, the subartesian groundwater appears to be the same, moderately saline

sodium bicarbonate type which is characteristic of most artesian water in the QMDB including the

Condamine section, although in these cases the relationship between artesian and subartesian systems is

not always clear. Highly saline waters, dominated by sodium chloride, also occur in the artesian system,

probably related to the depth of aquifers or other basement features, mainly along the extension of the

Kumbarilla Ridge in the middle of the catchment or downstream where the Condamine joins the Balonne.

8.4. Balonne–Culgoa

The Balonne–Culgoa River system includes the middle and lower reaches of the Condamine Balonne

downstream of the Darling Downs (Basin 4222), including tributaries. This is a major basin in terms of the

state's water resources. Most of the groundwater quality data is from artesian bores, but the subartesian

presence is still substantial, with most bores being deeper than 60 metres. The north-westerly flowing


25

Condamine becomes the Balonne near Surat, where it then veers in a more southerly direction. At

Beardmore Dam, upstream of St George, it joins the southward flowing Maranoa River (Basin 4224), its

headwaters extending well to the north of the Balonne catchment. Then, about 70 km downstream of St

George, the river enters a braided fan where it splits into the Culgoa and the Narran. The Narran

subsequently splits into further channels before crossing the NSW border. The Nebine catchment (Basin

4225), located at the western end of the Balonne–Culgoa system, includes Nebine, Mungallala and Wallam

Creeks which flow southward over the NSW border to join the Culgoa River. Groundwater data is more

substantial than surface water data in this region, but is mainly from artesian bores. However large

subartesian or semi-confined aquifers do occur, at depths usually exceeding 60 metres. In terms of surface

water, the Balonne is an important resource, supplying the St George irrigation area via the Beardmore

Dam.

The ground and surface water are chemically distinct over most of this area, suggesting limited contact with

slow, if any, interchange. The surface water, in common with surface water in the bulk of the western

QMDB (McNeil et al. 2005), is mostly a low salinity bicarbonate type with evenly proportioned cations, or,

to a lesser extent, slight sodium dominance. The subartesian waters are highly varied, indicating

fragmentation and a variety of sources. However, they are mainly divided between a moderately saline,

sodium bicarbonate type, and a highly saline sodium chloride type. These are the same chemical types

found over most of the artesian system. The sodium bicarbonate type is the most common. The sodium

chloride type increases in prominence with depth, and can be of very high salinity if deeper than 60 m

particularly in the Nebine Catchment. Such groundwaters develop in flatter areas in dry climates because

salts deposited by rainfall tend to accumulate as the water is lost to evaporation. The salt is then leached

towards the water table by subsequent recharge events (Herczeg et al. 2001). Variability in composition

increases west of Beardmore Dam, particularly at moderate depths. High sulfate levels, a significant feature

of very deep groundwaters in the western areas of the Maranoa and Nebine catchments, are probably

related to the presence of gypsum in the landscape. A number of other water types are locally prominent in

the subartesian system, particularly at moderate depths in the Maranoa and in the deepest levels of the

Nebine, suggesting poor hydraulic connectivity, diverse local influences, or stagnation.

Artesian bores are concentrated in the northern half of the Balonne catchment between Chinchilla and

Surat, and in the headwaters of the Maranoa. They are also distributed throughout the braided channels in

the lower catchment, the mid and lower reaches of the Maranoa River, and most of the Nebine catchment.

Average depths are around 60–100 m, but bores with depths of 500 m to over 1,000 m are scattered

through the catchment, presumably accessing deeper aquifers. The predominant water chemistry is the

moderately saline, sodium bicarbonate type common to most of the QMDB, but complexity increases

towards the west. High salinity sodium chloride water constitutes much of the remaining artesian

chemistry, and its composition may be influenced by contact with subartesian groundwaters from the

Cenozoic alluvium or GAB Cap. It occurs sporadically, usually at depths of around 80–180 m, but is more

concentrated in certain areas. These include an extension of the Kumbarilla Ridge in the eastern corner of

the catchment; the middle courses of the Balonne and Maranoa rivers upstream of their confluence; the

downstream braided channels; and across the central Nebine subcatchment and its border with the

Maranoa. The Nebine subcatchment also includes some high salinity bores with a lower sodium

composition.

This catchment contains one area where the chemistry is highly atypical of QMDB artesian bores in general.

This comprises the northern headwaters of the Maranoa River, where the bores are unusually shallow,

many being less than 20 m and most less than 100 m, and the chemistry is very variable. The only

substantive types are low salinity bicarbonates with balanced cations, or with sodium slightly exceeding


26

calcium, and a moderately saline chloride type which is low in sodium. Low salinities showing similarities

with the surface waters in this region support the identification of the upper channel of the Maranoa River

as a recharge source (Herczeg 2008).

8.5. Western streams

The western streams of the QMDB include the Warrego (Basin 4232), Paroo (Basin 4242) and Bulloo (Basin

0112) Catchments. These comprise large, low relief, inland river systems, extending northward to approach

the headwaters of the Burdekin basin, and bordering the Lake Eyre basin to the west. The climate is semi-

arid with summer-dominant rainfall, and the rivers usually have a well-defined channel consisting of a

string of waterholes some of which are permanent. The lower courses of the drainage systems flow in

braided channels over alluvial fans which under present climatic conditions only reach the Darling and

Culgoa rivers in NSW during large floods. There has been little hydrological modification, and grazing is the

dominant land use.

Both the Warrego and Paroo catchments are important in terms of water resource development and

collected data, and although the surface water may be of local importance, the collected data is virtually all

from groundwater and mainly from artesian bores. There are substantial beds of subartesian water in the

Warrego and Bulloo, most of it being deeper than 60 metres. Chemical differences between surface,

subartesian and artesian waters vary through the area, with strongest associations being in the Warrego,

identified as a potential GAB recharge source (Kellett et al. 2003), and very little similarity in the Bulloo,

suggesting limited contact and slow interchange.

Most of the surface water is the low salinity bicarbonate type which is typical of the western QMDB, with

either evenly proportioned cations or occasionally dominated by sodium. This type also occurs in shallow

groundwaters throughout the region, and In the Warrego extends to the deep subartesian waters,

particularly near the river. However, the groundwater chemistry tends to be very variable over much of the

area because of poor hydraulic connectivity, diverse local influences, or flow stagnation at any depth. One

such type is high in sulfate and tends to be very saline. It is an important component of the shallower

groundwaters of the Paroo and Bulloo catchments, possibly as result of gypsum in the soils. However the

bulk of the subartesian waters are highly saline sodium chloride types, sometimes becoming very saline

below 45 metres. This highly saline water is sometimes present in the Paroo River, and probably originates

from seepages through the Cainozoic alluvium or GAB Cap.

This area has a high density of artesian bores except in the upper Warrego and lower western side of the

Bulloo catchments. Average depths are around 40–90 m, although some extend to over 1,000 metres. The

highly saline sodium chloride type is scattered through the artesian waters, usually at comparatively

moderate depths, and particularly in areas such as the downstream braided channels, the Paroo catchment

away from the mainstream including Lake Numalla, and around the western border of the Bulloo

catchment. In common with the Maranoa headwaters, also noted as a recharge area, artesian bores in the

northern headwaters of the Warrego are atypical, having a low salinity bicarbonate chemistry with

balanced cations or occasional sodium dominance, which closely resembles that of the local surface and

subartesian waters.

9. References

Anderson, T. et al., 2010. Groundwater bore deterioration: schemes to alleviate rehabilitation costs,

National Water Commission, Canberra.


27

Biggs, A., 2014. Bacteria down a bore – anecdotes from southern inland Queensland. ASSAY, vol. 64, pp. 2–

3.

Biggs, J.S., Keating, D.S., Thorburn, P.J., 2000. Time trends in nitrate in groundwaters under intensive

agriculture in the Bundaberg Region. Proceedings of the Society of Sugar Cane Technology, vol. 22, pp. 296–

301.

Braaten, R., Gates, G., 2004. Lagging behind: exploring the time lag in river–aquifer interaction, In:

Proceedings of the 9th Murray-Darling Basin Groundwater Workshop. Bendigo, 17–19 February 2004,

Murray–Darling Basin Commission, Canberra.

Dafny E., Silburn D.M., 2013. The hydrogeology of the Condamine River Alluvial Aquifer (Australia) - critical

review. University of Southern Queensland, Toowoomba, Australia.

Day, R.W., 1983. Queensland Geology: A companion volume to the 1: 2,500,000 scale geological map.

(1975) (No. 383), Geological Survey of Queensland.

Decelles, P., 2002. The pH Scale. Virtually Biology Course, Basic Chemistry Concepts, Johnson County

Community College, http://staff.jccc.net/pde-cell/chemistry/phscale.html (accessed July 14, 2013).

Department of Environment and Heritage Protection 2009. Queensland Water Quality Guidelines, Version

3, ISBN 978-0-9806986-0-2.

Esterle, JS, Hamilton, SK, Ward, V, Tyson S, Sliwa, R, 2013. Scales of Geological Heterogeneity within the

Walloon Subgroup and its Coal Measures. February 2013. Final report of Activity 1.3 of the Healthy

HeadWaters Coal Seam Gas Water Feasibility Study. Department of Natural Resources and Mines.

Exon, N.F., Galloway, M.C., Casey, D.J. Kirkegaard, A.G., 1966. The geology of the Tambo, Augathella and

Blackall 1:250,000 Sheet Areas, Queensland. 1966/89, Bureau of Mineral Resources, Geology and

Geophysics.

Galloway, R.W. (Editor), 1974. Lands of the Balonne-Maranoa Area, Queensland. Land Research Series

No.34; CSIRO, Australia, 238 pp.

GHD, 2010. Groundwater bore deterioration: schemes to alleviate rehabilitation costs. Waterlines report,

National Water Commission, Canberra

Green, D., Ali, A., Petrovic, J., Burrell, M, Moss, P., 2012. Water resource and management overview:

Border Rivers Catchment, NSW Department of Primary Industries, Sydney.

Herczeg, A.L., 2008. Background report on the Great Artesian Basin, A report to the Australian Government

from the CSIRO Murray-Darling Basin Sustainable Yields Project. CSIRO, Australia.

Herczeg, A.L., Dogramaci, S.S., Leaney, F.W.J., 2001. Origin of dissolved salts in a large, semi-arid

groundwater system: Murray Basin, Australia. Marine and Freshwater Research, vol. 52(1), pp. 41–52.

Kellett, J.R. 2003. Groundwater Recharge in the Great Artesian Basin Intake Beds, Queensland, Queensland

Department of Natural Resources and Mines Technical Report, Brisbane.

Kingham, R., 1998. Geology of the Murray-Darling Basin – simplified lithostratigraphic groupings. AGSO

Record 1998/21, Australian Geological Survey Organisation, Department of Primary Industries & Energy,

Canberra.


28

McNeil, V. H., Cox, M. E., Preda, M. 2005. Assessment of chemical water types and their spatial variation

using multi-stage cluster analysis, Queensland, Australia. Journal of Hydrology, vol. 310, pp. 181–200.

MDBA 2011. Acid Sulfate Soils in the Murray Darling Basin. MDBA Publication No. 147/11: Murray-Darling

Basin Authority (MDBA), on behalf of the Commonwealth of Australia 2009. 90 pp.

MDBC, 2005. Chapter 4: Connectivity of surface water and groundwater resources of the basin, In Summary

of Estimated Impact of Groundwater Use on Streamflow in the Murray-Darling Basin. Publication No. 03/07

Murray-Darling Basin Commission, Canberra, pp. 29–40.

Radke, B.M., Kellett, J.R., Ransley, T.R., Bell, J.G., 2012. Lexicon of the lithostratigraphic and hydrogeological

units of the Great Artesian Basin and its Cenozoic cover. A technical report to the Australian Government

from the CSIRO Great Artesian Basin Water Resource Assessment.

Raymond, M.A.A., McNeil, V.H., 2011. Regional Chemistry of the Fitzroy Basin Groundwater. Brisbane:

Department of Environment and Resource Management, Queensland Government.

Raymond, M.A.A., McNeil, V.H., 2013. Queensland Wet Tropics and Black and Ross catchments: Regional

chemistry of the groundwater: Department of Science, Innovation and the Arts, Queensland Government.

Reid M.A., Cheng X., Banks E.W., Jankowski J., Jolly I., Kumar P., Lovell D.M., Mitchell M., Mudd G.M.,

Richardson S., Silburn M., Werner A.D. 2009. Catalogue of conceptual models for groundwater–stream

interaction. eWater Technical Report. eWater Cooperative Research Centre, Canberra.

Schulz, C., Steward, A.L., Prior, 2013. Stygofauna presence within fresh and highly saline aquifers of the

border rivers region in Southern Queensland. Proceedings of the Royal Society of Queensland, vol. 118, pp.

27–35.

Seitzinger, S., Harrison, J.A., Böhlke, J.K., Bouwman, A.F., Lowrance, R., Peterson, B., Tobias, C., Van Drecht.,

G. 2006. Denitrification across landscapes and waterscapes: a synthesis. Ecological Applications, vol. 16(6),

pp. 2064–2090.

Smerdon B.D., Ransley T.R., Radke B.M., Kellett, J.R. 2012. Water resource assessment for the Great

Artesian Basin. A report to the Australian Government from the CSIRO Great Artesian Basin Water Resource

Assessment. CSIRO Water for a Healthy Country Flagship, Australia


29

10. Tabulated results

The information in Tables 2 and 3 apply to the groundwater zones outlined on Figures 5–13. A brief

description of the zone characteristics are provided in Table 2, percentile ranges of water quality

parameters at each zone provided in Table 3.

30

Table 2 Detailed description of water chemistry in each nominated groundwater zone of the QMDB

Map division Zone Data sufficiency Dominant Ions All surface water

Percentiles (EC µS cm-1)

Description

Cations Anions 20th 50th 80th

Alluvium 1 Southern Condamine

excellent balanced HCO3 moderate 680 990 1480 Moderately saline: no dominant cations, HCO3. For general use, the water is hard with occasional scaling. Water levels may have fallen over the last 20 years, while EC and NO3 may have risen.

Alluvium 1 Southern Condamine - near stream

balanced HCO3 moderate 689 981 1400 Moderately saline: no dominant

cations, HCO3.

Alluvium 2 Central Condamine

good Na HCO3 moderate 603 1160 2800 Moderately saline: Na HCO3. EC maybe excessive for sensitive crops Water levels may have fallen over the last 20 years, while EC and NO3 may have risen.

Alluvium 2 Central Condamine - near stream

Na HCO3

moderate 580 890 1675 Moderately saline: Na HCO3.

Alluvium 3 North Branch excellent Na Ca HCO3 moderate 660 805 1050 Moderately saline: Na > Ca, HCO3. For general use, the water is hard. Water levels may have risen over the last 20 years, while EC and NO3 may have fallen.

Alluvium 3 North Branch - near stream

Na Ca HCO3 moderate 603 720 987 Moderately saline: Na > Ca, HCO3.

Alluvium 4 Hodgson moderate Na Cl high 1927 3575 7049 Saline: Na Cl. For general use, the water is saline and hard with some scale. EC and sometimes Na maybe excessive for sensitive crops Water levels may have fallen over the last 20 years, while EC and NO3 may have risen.

31



Description


Alluvium 5 Oakey good Na Cl high 1800 2750 4400 Saline: Na Cl. For general use, the water is saline and hard with some scale. EC and sometimes Na maybe excessive for sensitive crops Water levels probably fell over the last 20 years while EC and NO3 appear to be stable.

Alluvium 5 Oakey - near stream

Na Cl high 1150 2378 3410 Saline: Na Cl.

Alluvium 6 Myall moderate Na Cl high 1629 2150 3150 Saline: Na Cl. For general use, the water is saline and hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops Water levels may have risen over the last 20 years but there is insufficient data to comment on water quality trends.

Alluvium 6 Myall - near stream


Alluvium 7 Northwest Condamine

moderate Na Cl high 2400 4740 9200 Saline: Na Cl. For general use, the water is saline and hard with some scale. EC and sometimes Na maybe excessive for sensitive crops Water levels, EC and NO3 may all have dropped over the last 20 years.

Alluvium 7 Northwest Condamine - near stream

Na Cl high EC

variable 1380 2600 11050 High salinity but EC can be variable:

Na Cl.

32



Description


Alluvium 8 Lower Condamine moderate Na Cl high EC variable

625 2700 9910 High salinity but EC can be variable: Na Cl. For general use, the water is saline and hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops Water levels may have fallen over the last 20 years but there is insufficient data to comment on water quality trends.

Alluvium 8 Lower Condamine - near stream

Na Cl high EC


Na Cl.

Alluvium 9 Wooloowins good Na Mg Cl high 1400 2047 3000 Saline: Na > Mg, Cl. For general use, the water is saline and hard with some scale. EC maybe excessive for sensitive crops Water levels, EC and NO3 may all have dropped over the last 20 years.

Alluvium 9 Wooloowins - near stream

Na Mg Cl high 1350 2270 3456 Saline: Na > Mg, Cl.

Alluvium 10 Upper Balonne occ corrodev poor Na Cl very high EC variable

3442 8380 21150 Very high salinity but EC can be variable: Na Cl. For general use, the water is saline and hard with some scale. EC may be excessive for irrigation and Na at times for sensitive crops. Water levels may have fallen over the last 20 years, while EC and NO3 may have risen although data is poor.

Alluvium 10 Upper Balonne - near stream

Na Cl very high 2567 19300 21590 Very Saline: Na Cl.

33



Description


Alluvium 11 Border Rivers v poor Na Cl high EC variable

531 1800 23910 High salinity but EC can be variable: Na Cl. For general use, the water is saline. EC and sometimes Na maybe excessive for sensitive crops Water levels may have fallen over the last 20 years, while EC and NO3 may have risen.

Alluvium 11 Border Rivers - near stream

Na Cl HCO3 moderate

EC variable 330 820 14150 Moderate salinity but EC can be

variable: Na, Cl > HCO3.

Alluvium 13 Upper Dumaresq

good Na Ca HCO3 moderate 504 843 1104 Moderately saline: Na > Ca, HCO3. Water levels may have fallen over the last 20 years, while EC and NO3 may have risen.

Alluvium 13 Upper Dumaresq - near stream

Na Ca HCO3 moderate 498 833 1103 Moderately saline: Na > Ca, HCO3.

Alluvium 14 Macintyre Brook moderate Na HCO3 moderate 410 1178 1700 Moderately saline: Na HCO3. EC maybe excessive for sensitive crops There is insufficient data to comment on trends in this zone.

Alluvium 14 Macintyre Brook - near stream

Na HCO3 moderate 412 1178 1700 Moderately saline: Na HCO3.

Alluvium 15 Lower Maranoa moderate Na Cl high EC variable

528 1528 4403 High salinity but EC can be variable: Na Cl. EC and sometimes Na maybe excessive for sensitive crops Water levels may have risen over the last 20 years, while EC and NO3 may have fallen.

34



Description


Alluvium 15 Lower Maranoa - near stream

Na Cl HCO3 high EC


Na, Cl > HCO3.

Alluvium 16 Lower Balonne v poor Na Cl high 822 3460 5705 Saline: Na Cl. For general use, the water is saline and hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops Water levels may have fallen over the last 20 years, while EC and NO3 appear stable although data is poor.

Alluvium 16 Lower Balonne - near stream


Alluvium 17 Moonie some corrode unreliable

Na Cl very high 26460 46150 56280 Very Saline: Na Cl. For general use, the water is saline and hard with occasional scaling. EC may be excessive for irrigation and also stock. Na may be excessive for sensitive crops. Water levels may have fallen over the last 20 years, although data is poor. There is insufficient data to comment on water quality trends.

Alluvium 18 Wallam unreliable Na Cl moderate EC variable

0 1100 6005 Moderate salinity but EC can be variable: Na Cl. For general use, the water is hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops Water levels may have fallen over the last 20 years, although data is poor. There is insufficient data to comment on water quality trends.

35



Description


Alluvium 19 Upper Warrego v poor Na Cl HCO3 moderate EC variable

0 1000 2100 Moderate salinity but EC can be variable: Na, Cl > HCO3. EC maybe excessive for sensitive crops Water levels may have fallen over the last 20 years, although data is poor. There is insufficient data to comment on water quality trends.

Alluvium 19 Upper Warrego - near stream

Na Cl HCO3 moderate


variable: Na, Cl > HCO3.

Alluvium 20 Lower Warrego v poor Na Cl HCO3 moderate EC variable

118 611 18550 Moderate salinity but EC can be variable: Na, Cl > HCO3. Na is occasionally excessive for sensitive crops There is insufficient data to comment on trends in this zone.

Alluvium 20 Lower Warrego - near stream

Na HCO3 moderate


variable: Na HCO3. For general use, the water is hard. EC maybe excessive for sensitive crops Water levels appear to have been stable over the last 20 years, while EC and NO3 may have fallen.

Fractured Rock

1 Upper Condamine basalts

moderate Mg Na HCO3 moderate 687 1040 1493 Moderately saline: Mg > Na, HCO3.

36



Description


Fractured Rock

2 Toowoomba Region Basalts

excellent Mg Na HCO3 Cl moderate 660 1200 1750 Moderately saline: Mg > Na, HCO3 > Cl. For general use, the water is hard with some scale. EC maybe excessive for sensitive crops Water levels, EC and NO3 may all have dropped over the last 20 years.

Fractured Rock

3 Lower Condamine Basalts

moderate Na Mg HCO3 Cl moderate 790 1400 2568 Moderately saline: Na > Mg, HCO3 > Cl. For general use, the water is hard with some scale. EC maybe excessive for sensitive crops Water levels may have risen over the last 20 years, while EC and NO3 may have fallen.

Fractured Rock

4 Eastern Basement With Basalt Remnants

v poor Na HCO3 moderate 1033 1500 2922 Moderately saline: Salinity may affect taste, and they may not be ideal for other general purposes because of the high EC, hardness and pH.

Fractured Rock

5 Main Range Volcanics

v poor Na Mg HCO3 moderate 688 1032 1866 Moderately saline: Na > Mg. Salinity may affect taste, particularly in the deeper groundwaters, and they may not be ideal for other general purposes because of the high EC and hardness.

37



Description


Fractured Rock

6 Border Rivers Headwaters

v poor Na Ca Cl high EC variable

648 1550 4212 High salinity but EC can be variable: Na > Ca. For general use, the water is hard with occasional scaling. EC maybe excessive for sensitive crops Water levels, EC and NO3 may all have dropped over the last 20 years, although data is poor.

Fractured Rock

7 Glenlyon v poor Na Ca HCO3 Cl moderate 230 2014 2125 Moderately saline: Na > Ca, HCO3 > Cl. For general use, the water is hard with occasional scaling. Water levels may have risen over the last 20 years, although data is poor. There is insufficient data to comment on water quality trends.

Fractured Rock

8 New England Granite

occ corroded poor

Na Cl moderate 273 600 1225 Moderately saline: Na Cl Water levels appear to have been stable over the last 20 years. There is insufficient data to comment on water quality trends.

Deposits overlying GAB

1 Weathered Alluvium

v poor Na Cl high EC variable

624 2690 22710 High salinity but EC can be variable: Na Cl. For general use, the water is saline and hard. EC and sometimes Na maybe excessive for sensitive crops.


1 Weathered Alluvium - near stream

excellent Na HCO3 Cl moderate EC variable

525 1269 6400 moderate salinity but EC can be variable: Na, HCO3> Cl.

38



Description



3 Tertiary sediments

unreliable Na Cl moderate EC variable

0 1575 2180 Moderate salinity but EC can be variable: Na Cl. For general use, the water is soft but pH is high. Na may be excessive for irrigation and F for sensitive crops.

Upper GAB 1 Winton Mackunda Western

v poor Na Cl very low 0 0 3892 Very low salinity: Na Cl. For general use, the water is hard with occasional scaling. Na occasionally excessive for sensitive crops.

Upper GAB 3 Winton Mackunda Eastern


0 1976 7920 High salinity but EC can be variable: Na Cl. For general use, the water is saline and hard with some scale. EC and sometimes Na maybe excessive for sensitive crops.

Upper GAB 5 Central Upper Cretaceous

unreliable Na Cl high EC variable

546 1520 3745 High salinity but EC can be variable: Na Cl. EC and sometimes Na maybe excessive for sensitive crops.

Upper GAB 6 Probable Upper Cretaceous Aquitard

unreliable Na Cl high EC variable

1260 3150 8900 High salinity but EC can be variable: Na Cl. For general use, the water is saline and hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops.

39



Description


Main GAB aquitard

1 Eastern Wallumbilla Outcrop


877 2399 10000 High salinity but EC can be variable: Na Cl. For general use, the water is saline but soft. EC and sometimes Na maybe excessive for sensitive crops.

Main GAB aquitard

2 Wallumbilla Doncaster Outcrop

v poor Na Cl moderate EC variable

0 960 2200 Moderate salinity but EC can be variable: Na Cl. For general use, the water is hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops.

Main GAB aquitard

3 Central Surat Mid Cretaceous

v poor Na Cl very high 3151 24000 50690 Very Saline: Na Cl. For general use, the water is saline and hard with occasional scaling. EC may be excessive for irrigation and stock, and Na for sensitive crops.

Main GAB aquitard

4 Wallum Nebine Unproductive Area

v poor Na Cl high 1110 1500 3165 Saline: Na Cl. EC and sometimes Na maybe excessive for sensitive crops.

Main GAB aquitard

5 Coreena and Doncaster Nebine Ridge

v poor Na Cl high 998 1950 4300 Saline: Na Cl. For general use, the water is saline. EC and sometimes Na maybe excessive for sensitive crops.

Main GAB aquitard

6 Southern Wallumbilla Fresh Zone

v poor Na HCO3 moderate 760 900 1362 Moderately saline: Na HCO3. For general use, the water is soft. Na is occasionally excessive for sensitive crops.

Main GAB aquitard

7 South Western Eromanga Saline Zone


0 0 4400 Moderate salinity but EC can be variable: Na Cl. Na occasionally excessive for sensitive crops.

40



Description


Main GAB aquitard

8 Northern Eromanga Allaru and Toolebuc

unreliable Na Cl HCO3 moderate 0 1435 2725 Moderately saline: Na, Cl > HCO3 For general use, the water is soft. EC and at times Na maybe excessive for sensitive crops.

Main GAB aquitard

9 North Central Coreena


0 1100 3366 Moderate salinity but EC can be variable: Na Cl. For general use, the water is hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops.

Mid GAB aquifers

1 Northern Maranoa Bungils


0 0 2050 Moderate salinity but EC can be variable: Na Cl. Na occasionally excessive for sensitive crops.

Mid GAB aquifers

2 Central Mooga and Orallo Outcrops

poor Na HCO3 Cl moderate EC variable

0 1065 2145 Moderate salinity but EC can be variable: Na, HCO3 > Cl. EC and sometimes Na maybe excessive for sensitive crops.

Mid GAB aquifers

3 Eastern Cretaceous Outcrop

v poor Na Cl high 771 1650 3870 Saline: Na Cl. For general use, the water is soft. EC and sometimes Na maybe excessive for sensitive crops.

Mid GAB aquifers

4 Hooray Northern Outcrop

v poor Na Ca Cl HCO3 moderate EC variable

0 710 1650 Moderate salinity but EC can be variable: Na > Ca, Cl > HCO3.

41



Description


Mid GAB aquifers

5 Lower Balonne Gubberamunda

v poor Na HCO3 hard low moderate EC

1063 1360 2016 Hard Low Moderately saline: Na HCO3. For general use, the water is soft. Na maybe excessive for irrigation on susceptible soils, and EC for sensitive crops.

Mid GAB aquifers

6 North Wallumbilla Bungil and Mooga


0 2420 6454 High salinity but EC can be variable: Na Cl. For general use, the water is saline. EC and sometimes Na maybe excessive for sensitive crops.

Mid GAB aquifers

7 Northern Central Hooray

occ corrodev poor Na Cl moderate 626 1300 2355 Moderately saline: Na Cl. For general use, the water is soft. EC and sometimes Na maybe excessive for sensitive crops.

Mid GAB aquifers

8 Northern Surat Thickest Bungil and Mooga

v poor Na HCO3 hard low high

1400 1720 2026 Hard Low Saline: Na HCO3. For general use, the water is saline but soft. Na maybe excessive for irrigation on susceptible soils, and EC and F for sensitive crops.

Mid GAB aquifers

9 Northern Central Outcrop Area

v poor Na Cl HCO3 low EC variable

0 437 1739 Low salinity but EC can be variable: Na, Cl > HCO3.

Mid GAB aquifers

10 South Saline Gubberamunda

v poor Na Cl high 891 2400 5258 Saline: Na Cl. For general use, the water is saline. EC and sometimes Na maybe excessive for sensitive crops.

42



Description


Mid GAB aquifers

11 South-east Kumbarilla

poor Na HCO3 hard low high

1173 1600 2050 Hard Low Saline: Na HCO3. For general use, the water is soft. F may exceed drinking guidelines Na maybe excessive for irrigation on susceptible soils, and EC and F for sensitive crops.

Mid GAB aquifers

12 Southern Hooray Thinning Area

v poor Na HCO3 hard low moderate

725 862 1030 Hard Low Moderately saline: Na HCO3. For general use, the water is soft. Na occasionally excessive for sensitive crops.

Mid GAB aquifers

13 Surat Thicker Mooga Saline Area

occ corrodev poor Na Cl hard low high

1872 2308 2565 Hard Low Saline: Na Cl. For general use, the water is saline but soft. F may exceed drinking guidelines Na maybe excessive for irrigation on susceptible soils, and EC and F for sensitive crops.

Mid GAB aquifers

14 Western Hooray v poor Na HCO3 hard low moderate


Lower GAB 1 Central Surat Springbok Area


923 1269 1987 Hard Low Moderately saline: Na HCO3. For general use, the water is soft. EC and sometimes Na maybe excessive for sensitive crops.

43



Description


Lower GAB 2 Eastern Springbok Outcrop


963 2925 9021 High salinity but EC can be variable: Na Cl. For general use, the water is saline with some scale. EC and sometimes Na maybe excessive for sensitive crops.

Lower GAB 3 Fresh Hutton South-eastern Outcrop

moderate Na Cl high 1400 2150 3790 Saline: Na Cl. For general use, the water is saline and hard. EC maybe excessive for sensitive crops.

Lower GAB 4 North East Walloons

poor Na Cl high 1650 3500 9015 Saline: Na Cl. For general use, the water is saline and hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops.

Lower GAB 5 North-eastern Hutton Outcrop



Lower GAB 6 Northern Hutton Outcrop

v poor Na Ca HCO3 moderate 0 538 910 Moderately saline: Na > Ca, HCO3.

Lower GAB 7 Northern Walloons

v poor Na Cl high 854 1600 5145 Saline: Na Cl. For general use, the water is saline but soft. EC and sometimes Na maybe excessive for sensitive crops.

44



Description


Lower GAB 8 Saline South-eastern Hutton Outcrop



Lower GAB 9 South East Walloons

moderate Na HCO3 moderate 880 1500 2550 Moderately saline: Na HCO3. For general use, the water is hard with occasional scaling. EC and sometimes Na maybe excessive for sensitive crops.

Lower GAB 10 South-eastern Hutton Outcrop

moderate Na Ca Cl high 1111 1817 3895 Saline: Na > Ca, Cl. For general use, the water is saline and hard with occasional scaling. EC maybe excessive for sensitive crops.

Lower GAB 11 Southern Limit of Adori

v poor Na HCO3 moderate 461 562 1333 Moderately saline: Na HCO3. Na occasionally excessive for sensitive crops.

Lower GAB 12 Hutton Western Eromanga Region

v poor Na HCO3

HCO3

hard low moderate


Basal GAB 1 Precipice Outcrop v poor balanced HCO3 low 247 340 440 Low salinity: no dominant cations, HCO3.

45



Description


Basal GAB 2 Eastern Central Area


185 1040 1463 Hard Low Moderately saline: Na HCO3. For general use, the water is soft. EC and sometimes Na or F may be excessive for sensitive crops.

Basal GAB 3 North-eastern Evergreen Outcrop

unreliable Na Cl high 1295 2975 5505 Saline: Na Cl. For general use, the water is saline. Na maybe excessive for irrigation on susceptible soils, and EC for sensitive crops.

Basal GAB 4 South-eastern Evergreen

v poor Na Cl high 920 2300 3634 Saline: Na Cl. For general use, the water is saline and hard with some scale. EC and sometimes Na maybe excessive for sensitive crops.

Basal GAB 5 North-western Evergreen Outcrop

occ corrodev poor balanced Cl HCO3 low EC variable

149 247 889 Low salinity but EC can be variable: no dominant cations, Cl > HCO3.

Basal GAB 6 Western Evergreen Only

unreliable Na HCO3 hard low moderate


Earlier basins partially underlying the GAB

1 Bowen Basin v poor Na HCO3 hard low high

190 1550 2957 Hard Low Saline: Na HCO3. For general use, the water is saline and relatively soft, but pH maybe high. EC and sometimes Na and F may be excessive for irrigation, and EC for sensitive crops F may be excessive for stock.

46



Description



2 Upper Bowen Basin

v poor Na HCO3 hard low high

190 1550 2957 Hard Low Saline: Na HCO3. For general use, the water is saline and relatively soft, but pH maybe high. EC and sometimes Na and F may be excessive for irrigation, and EC for sensitive crops F may be excessive for stock.


3 Galilee Basin v poor Na HCO3 moderate 450 571 1252 Low to moderate salinity. Insufficient data to rate the water for drinking or general purposes, but it tends to be corrosive.

47

Table 3 Statistical summaries of water chemistry within each nominated QMDB groundwater zone

Zone %ile Na Ca Mg HCO3 Cl SO4 NO3 EC Hard pH Alk SiO2 F Fe Mn Zn Cu SAR TN TP

mg/L % mg/L % mg/L % mg/L % mg/L % mg/L % mg/L % µS/cm mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L meq/L mg/L mg/L

Alluvium

1 - Southern Condamine

20th 44 22 36 17 27 27 281 49 56 18 0.5 0 0.00 0 680 217 7.5 245.0 28.0 0.10 0.005 0.000 0.005 0.010 1.00 0.000 0.000

50th 78 33 55 27 49 36 428 69 103 29 4.7 1 1.00 0 990 350 7.9 365.0 36.0 0.20 0.010 0.010 0.005 0.015 1.80 0.207 0.033

80th 156 51 84 36 80 47 592 81 245 47 15.0 2 8.50 1 1480 522 8.2 500.0 44.0 0.25 0.050 0.293 0.010 0.015 3.80 1.804 0.225

1 - Southern Condamine near stream

20th 43 21 38 17 28 27 291 50 54 17 0.5 0 0.00 0 689 228 7.5 254.0 28.0 0.10 0.005 0.000 0.005 0.010 1.00 0.000 0.000

50th 75 32 56 28 50 36 433 71 97 28 4.2 1 0.90 0 981 353 7.9 373.0 36.0 0.20 0.010 0.010 0.005 0.015 1.70 0.196 0.033

80th 150 49 84 36 77 47 589 82 225 46 13.0 2 8.00 1 1400 508 8.2 499.0 44.0 0.24 0.040 0.309 0.011 0.015 3.60 1.739 0.229

2 - Central Condamine

20th 85 54 19 7 13 12 239 24 70 28 5.0 1 0.20 0 603 110 7.4 200.0 27.0 0.10 0.005 0.005 0.005 0.015 3.20 0.043 0.000

50th 213 71 34 12 24 16 382 54 170 40 22.0 4 0.50 0 1160 183 7.9 321.0 33.0 0.16 0.010 0.010 0.005 0.015 7.30 0.109 0.033

80th 535 80 61 23 54 25 465 69 739 72 84.7 7 2.00 0 2800 364 8.3 390.0 40.0 0.30 0.050 0.050 0.010 0.015 12.80 0.435 0.154

2 - Central Condamine near stream

20th 63 42 18 8 14 13 210 42 64 27 4.2 1 0.25 0 580 107 7.3 173.9 24.0 0.10 0.005 0.005 0.005 0.015 2.10 0.053 0.000

50th 134 64 32 16 23 20 352 61 120 37 12.5 3 0.50 0 890 179 7.9 291.0 32.0 0.15 0.010 0.010 0.005 0.015 4.50 0.109 0.033

80th 316 78 50 28 36 29 445 71 285 57 58.0 7 2.50 0 1675 264 8.3 375.0 38.0 0.30 0.103 0.150 0.010 0.015 10.15 0.543 0.163

3 - North Branch

20th 83 46 27 15 17 17 280 59 54 20 4.0 1 0.00 0 660 146 7.5 240.0 28.0 0.10 0.005 0.005 0.005 0.015 2.50 0.000 0.000

50th 105 55 37 21 26 23 380 71 80 26 9.6 2 0.50 0 805 203 7.9 320.0 36.0 0.10 0.010 0.010 0.005 0.015 3.30 0.109 0.033

80th 158 66 52 28 34 28 451 77 136 38 26.0 5 1.00 0 1050 256 8.3 376.0 40.0 0.20 0.030 0.010 0.010 0.015 4.90 0.217 0.098

3 - North Branch near stream

20th 66 40 26 18 15 17 235 60 51 21 2.2 1 0.00 0 603 134 7.5 201.5 27.0 0.10 0.005 0.004 0.001 0.010 2.10 0.020 0.000

50th 92 53 36 24 20 22 332 72 70 27 5.6 2 0.50 0 720 175 7.9 277.0 34.0 0.10 0.010 0.010 0.005 0.015 3.00 0.109 0.098

80th 123 63 64 32 33 28 432 78 119 39 12.0 3 1.20 0 987 264 8.2 364.0 40.0 0.25 0.030 0.010 0.005 0.015 4.00 0.241 0.154

4 - Hodgson

20th 381 65 31 5 47 15 353 9 400 47 65.8 6 0.50 0 1927 295 7.4 307.2 20.0 0.15 0.005 0.005 0.005 0.015 8.10 0.109 0.000

50th 617 73 59 8 83 20 458 25 818 66 198.5 9 1.80 0 3575 479 7.8 392.5 27.5 0.20 0.010 0.010 0.005 0.015 13.10 0.391 0.000

80th 1176 79 107 11 181 24 567 41 1890 80 440.7 15 5.00 0 7049 918 8.3 518.6 32.1 0.50 0.050 0.050 0.020 0.035 18.60 1.087 0.065

5 - Oakey

20th 313 71 23 5 31 11 358 15 279 41 33.5 3 0.50 0 1800 198 7.6 300.5 24.0 0.10 0.005 0.000 0.005 0.015 9.31 0.109 0.000

50th 490 77 38 7 50 16 450 28 631 65 86.0 6 1.25 0 2750 304 8.0 375.0 29.0 0.20 0.010 0.010 0.005 0.015 12.90 0.304 0.000

80th 782 83 79 9 96 20 600 52 1201 79 165.0 9 3.97 0 4400 586 8.4 515.5 35.0 0.40 0.050 0.020 0.005 0.015 16.49 1.017 0.033

5 - Oakey near stream

20th 228 68 19 5 22 10 360 23 217 46 20.6 2 0.06 0 1150 149 7.5 298.6 25.1 0.10 0.000 0.000 0.002 0.015 7.57 0.013 0.000

50th 380 76 37 8 49 16 455 31 550 61 74.5 7 1.33 0 2378 301 8.0 379.5 32.0 0.20 0.010 0.005 0.005 0.015 10.87 0.288 0.016

80th 620 84 59 14 68 20 511 46 757 71 143.7 10 3.00 0 3410 394 8.3 443.0 37.0 0.30 0.067 0.020 0.005 0.015 15.42 0.652 0.033

6 - Myall

20th 265 67 30 6 34 11 382 23 305 49 15.7 2 0.23 0 1629 215 7.5 330.0 24.0 0.10 0.000 0.005 ID ID 7.28 0.109 ID

50th 359 72 44 10 45 18 454 35 472 62 42.8 4 0.60 0 2150 294 8.0 382.0 28.0 0.20 0.020 0.020 ID ID 9.40 0.207 ID

80th 593 81 63 13 66 22 560 47 791 72 73.4 6 4.00 0 3150 427 8.4 468.3 32.0 0.40 0.031 0.070 ID ID 14.32 0.957 ID

48



6 - Myall near stream

20th 403 72 31 5 34 10 352 19 407 55 39.3 3 0.00 0 1970 213 7.5 318.2 22.3 0.18 0.000 0.000 ID ID 10.94 0.083 ID

50th 570 79 41 8 45 13 459 24 784 71 60.0 5 0.50 0 3080 269 8.0 385.0 27.8 0.30 0.020 0.020 ID ID 13.70 0.109 ID

80th 814 84 74 11 87 17 619 44 1213 75 117.1 6 3.41 0 3995 527 8.5 555.2 32.7 0.40 0.033 0.070 ID ID 16.58 0.865 ID

7 - Northwest Condamine

20th 489 65 34 5 35 11 332 8 577 60 36.5 2 0.10 0 2400 274 7.4 309.1 25.0 0.20 0.005 0.009 0.005 0.015 9.90 0.020 0.000

50th 830 76 82 9 92 16 462 15 1380 80 120.0 5 1.30 0 4740 582 7.8 394.5 37.0 0.40 0.020 0.050 0.010 0.030 15.30 0.283 0.000

80th 1549 81 180 17 208 21 575 33 3079 88 180.5 7 5.00 0 9200 1260 8.2 487.7 49.0 0.60 0.070 0.243 0.025 0.075 19.99 1.176 0.033

7 - Northwest Condamine near stream

20th 258 53 20 5 19 10 255 6 195 43 8.0 1 0.48 0 1380 135 7.3 221.0 18.6 0.23 ID ID ID ID 5.03 0.103 ID

50th 544 77 42 8 41 16 477 24 680 71 19.5 2 5.55 0 2600 321 7.9 405.0 26.0 0.53 ID ID ID ID 11.94 1.207 ID

80th 1795 84 145 22 196 27 554 55 3432 90 216.3 4 11.20 1 11050 1093 8.3 509.0 49.6 0.83 ID ID ID ID 22.95 2.435 ID

8 - Lower Condamine

20th 110 65 9 3 10 8 152 7 96 45 9.9 2 0.10 0 625 65 7.3 133.0 13.0 0.15 0.005 0.000 ID ID 4.70 0.028 ID

50th 586 79 40 7 37 14 330 17 608 77 54.5 5 0.50 0 2700 256 7.8 276.0 33.0 0.30 0.100 0.040 ID ID 18.10 0.109 ID

80th 1889 87 130 14 164 21 616 44 2930 87 220.5 8 4.01 0 9910 997 8.2 511.5 57.3 0.80 0.630 0.295 ID ID 28.70 0.274 ID

8 - Lower Condamine near stream

20th 74 61 10 4 10 8 136 5 77 45 13.7 3 0.11 0 563 77 7.2 116.0 13.0 0.10 0.019 0.000 ID ID 4.00 0.020 ID

50th 320 74 38 8 31 16 307 18 450 73 58.5 5 0.50 0 1950 230 7.8 256.5 30.0 0.30 0.100 0.053 ID ID 13.25 0.087 ID

80th 1926 86 128 16 185 22 464 47 3300 88 228.7 9 4.46 1 10440 1094 8.1 398.0 61.0 0.70 0.960 0.295 ID ID 28.12 0.191 ID

9 - Wooloowins

20th 134 38 37 10 43 19 275 20 255 49 6.6 1 0.50 0 1400 297 7.5 238.8 28.0 0.19 0.005 0.000 0.005 0.010 2.80 0.109 0.000

50th 250 51 72 17 76 30 405 33 470 64 14.0 1 2.20 0 2047 495 7.9 340.0 36.0 0.27 0.020 0.010 0.005 0.015 5.00 0.478 0.000

80th 413 68 125 26 120 38 574 48 881 77 39.0 3 6.60 1 3000 780 8.2 481.0 44.0 0.40 0.050 0.020 0.013 0.015 8.55 1.174 0.033

9 - Wooloowins near stream

20th 155 38 37 9 51 23 240 17 299 53 7.8 1 0.50 0 1350 328 7.6 203.0 28.0 0.18 0.003 0.000 0.005 0.015 3.00 0.109 0.000

50th 262 48 82 18 99 32 391 27 600 70 15.0 1 2.30 0 2270 634 7.9 326.5 36.0 0.25 0.020 0.010 0.005 0.015 4.80 0.500 0.000

80th 399 65 146 27 145 37 570 44 1023 81 33.0 3 6.60 0 3456 921 8.2 475.7 43.0 0.40 0.070 0.020 0.010 0.015 7.80 1.304 0.033

10 - Upper Balonne

20th 611 66 71 9 45 9 169 2 942 68 78.8 3 0.00 0 3442 360 6.7 141.2 30.0 0.21 0.000 0.050 0.002 0.000 16.70 ID ID

50th 1530 78 172 11 124 15 392 5 2610 85 414.0 11 1.25 0 8380 943 7.4 323.0 51.5 0.24 0.025 0.277 0.061 0.017 22.00 ID ID

80th 3823 82 553 13 360 18 453 27 6876 86 1292.0 12 5.00 0 21150 2853 7.9 378.8 58.0 0.44 0.030 1.470 0.097 0.019 31.00 ID ID

10 - Upper Balonne near stream

20th 505 65 46 7 20 6 154 1 510 59 24.8 2 0.00 0 2567 182 6.6 126.4 29.7 0.20 0.000 0.010 0.004 0.007 11.67 ID ID

50th 3490 74 525 12 336 18 392 5 6000 85 1050.0 7 1.25 0 19300 2690 7.4 323.0 40.5 0.32 0.025 1.250 0.088 0.017 29.00 ID ID

80th 3952 84 564 13 363 18 481 38 6945 91 1372.0 13 5.63 0 21590 2898 7.9 398.3 72.0 0.56 0.156 1.672 0.097 0.051 31.90 ID ID

11 - Border Rivers

20th 150 57 13 4 10 6 110 2 117 36 15.1 3 0.27 0 531 78 6.5 104.4 31.0 0.16 0.000 0.005 0.005 0.013 4.95 0.085 0.000

50th 329 75 34 11 23 14 253 28 381 64 64.5 7 1.90 0 1800 169 7.3 214.0 60.0 0.30 0.010 0.040 0.020 0.015 17.00 0.543 0.049

80th 4589 89 710 19 569 22 489 57 8723 90 1100.0 10 12.50 0 23910 4399 8.0 413.8 81.0 0.90 0.056 9.740 0.160 0.070 35.70 2.717 1.235

20th 71 46 13 5 9 6 126 9 69 30 16.2 5 0.00 0 331 70 7.0 123.8 35.9 0.18 0.000 0.009 0.020 0.005 2.83 0.060 ID

50th 235 65 24 13 17 18 257 34 180 42 53.5 8 1.30 0 820 125 7.5 220.0 55.0 0.25 0.008 0.105 0.070 0.015 9.20 0.913 ID

49



11 - Border Rivers near stream

80th 1893 89 430 28 334 27 514 64 3871 81 808.1 14 12.50 1 14150 2423 8.0 422.9 71.7 0.69 0.041 5.240 0.160 0.073 21.52 2.717 ID

12 - Upper Maranoa

Insufficient data

13 - Upper Dumaresq

20th 58 49 18 18 9 15 140 38 42 22 4.9 2 0.00 0 504 83 7.1 115.0 20.3 0.30 0.000 0.000 0.000 0.012 2.29 0.000 0.000

50th 112 59 33 23 16 18 248 63 86 33 15.5 4 0.50 0 843 153 7.7 207.0 34.0 0.50 0.010 0.020 0.010 0.015 3.91 0.109 0.000

80th 147 66 58 29 27 22 412 73 152 53 34.0 8 2.26 1 1104 250 8.1 343.4 46.7 0.60 0.050 0.130 0.020 0.080 4.50 0.491 0.000

13 - Upper Dumaresq near stream

20th 58 49 18 18 9 15 140 38 41 22 4.9 2 0.00 0 498 83 7.1 115.0 20.1 0.30 0.000 0.000 0.000 0.012 2.29 0.000 0.000

50th 112 59 32 23 16 18 249 63 86 33 15.5 4 0.50 0 833 151 7.7 207.0 34.0 0.50 0.010 0.020 0.010 0.015 3.91 0.109 0.000

80th 147 66 58 29 27 22 416 73 151 52 32.5 7 2.17 1 1103 250 8.1 349.2 46.0 0.60 0.050 0.130 0.020 0.080 4.47 0.472 0.000

14 - Macintyre Brook

20th 44 47 3 2 1 2 145 32 46 27 1.1 1 0.03 0 410 16 7.5 132.3 10.3 0.20 0.005 0.005 ID ID 1.80 ID ID

50th 124 91 19 14 11 20 295 54 115 34 7.9 3 0.80 0 1178 76 7.9 243.3 39.5 0.41 0.005 0.005 ID ID 8.92 ID ID

80th 412 97 32 26 28 27 610 68 270 56 30.2 6 6.40 1 1700 203 8.6 558.8 43.7 0.89 0.121 0.834 ID ID 31.59 ID ID

14 - Macintyre Brook near stream

20th 44 47 4 3 1 3 162 32 45 29 1.3 1 0.07 0 412 17 7.4 132.9 10.9 0.20 0.005 0.005 ID ID 1.80 ID ID

50th 113 91 20 18 14 20 295 53 102 34 6.5 3 0.53 0 1178 111 7.8 243.3 39.5 0.41 0.005 0.013 ID ID 8.92 ID ID

80th 333 94 35 26 39 27 610 67 270 53 30.8 6 6.40 1 1700 266 8.5 503.0 44.6 0.87 0.154 0.838 ID ID 28.88 ID ID

15 - Lower Maranoa

20th 87 59 18 7 12 10 164 7 69 32 17.3 5 0.00 0 528 93 7.0 150.3 33.0 0.13 0.000 0.001 0.005 0.010 4.10 0.016 ID

50th 349 76 32 12 27 13 205 31 416 67 83.8 10 0.50 0 1528 199 7.9 183.0 52.0 0.20 0.005 0.005 0.005 0.015 11.00 0.054 ID

80th 777 83 95 16 70 22 256 60 1258 81 234.7 12 2.50 0 4403 521 8.3 216.9 69.3 0.31 0.005 0.118 0.010 0.015 15.00 0.543 ID

15 - Lower Maranoa near stream

20th 65 54 19 11 13 12 166 7 65 26 10.9 5 0.00 0 339 115 6.9 142.2 51.0 0.11 0.000 0.001 0.000 0.001 2.71 0.016 ID

50th 255 74 45 12 41 14 206 40 231 47 51.0 10 0.25 0 1580 273 7.6 170.5 54.0 0.18 0.005 0.005 0.005 0.015 8.05 0.054 ID

80th 932 76 130 20 81 26 311 69 1545 82 266.2 11 2.50 0 4740 659 8.2 260.2 74.4 0.22 0.005 0.188 0.010 0.015 15.55 0.543 ID

16 - Lower Balonne

20th 154 78 9 5 7 6 153 9 79 38 19.5 6 0.25 0 822 49 7.0 165.6 36.7 0.10 0.000 0.000 0.005 0.010 6.70 0.038 0.000

50th 677 83 38 7 27 9 258 42 888 75 184.5 10 2.50 0 3460 203 7.9 230.0 50.5 0.23 0.005 0.005 0.010 0.015 20.00 0.652 0.000

80th 1287 89 109 10 78 12 519 53 1828 80 372.4 12 6.00 1 5705 606 8.3 458.7 65.0 0.39 0.020 0.050 0.010 0.015 25.52 2.717 0.000

16 - Lower Balonne near stream

20th 282 78 8 3 6 4 323 25 174 38 30.9 6 0.25 0 1105 45 7.7 291.4 52.3 0.29 0.000 0.000 0.003 0.005 11.31 0.054 ID

50th 410 87 41 5 32 7 560 39 511 54 98.0 7 4.80 0 2140 231 8.2 482.0 65.0 0.38 0.005 0.005 0.010 0.013 18.15 1.043 ID

80th 909 93 69 10 49 12 860 52 1040 63 161.4 9 13.85 1 4259 386 8.4 709.1 72.0 0.59 0.068 0.017 0.010 0.015 24.76 3.011 ID

17 - Moonie

20th ID ID ID ID ID ID ID ID ID ID ID ID ID ID 26460 ID ID ID ID ID ID ID ID ID ID ID ID



50



18 - Wallam

20th 161 66 21 7 13 8 0 15 162 42 27.7 4 0.00 0 0 106 7.1 179.8 ID 0.18 ID ID ID ID 6.04 ID ID



19 - Upper Warrego

20th 51 53 16 11 7 12 85 21 45 28 19.9 6 0.00 0 0 74 7.1 103.0 32.0 0.20 0.000 0.000 ID ID 2.23 0.000 ID

50th 151 70 26 14 17 15 151 45 195 45 47.3 11 1.85 0 1000 137 7.7 136.0 61.0 0.30 0.000 0.010 ID ID 5.90 0.413 ID

80th 362 76 57 27 37 21 226 66 357 70 82.6 13 3.85 1 2100 299 8.2 209.1 65.0 0.43 0.040 0.048 ID ID 9.79 0.935 ID

19 - Upper Warrego near stream

20th 54 55 17 11 7 12 74 21 42 27 19.4 5 0.00 0 31 75 7.1 105.0 42.5 0.20 0.000 0.000 ID ID 2.55 0.000 ID

50th 151 70 26 13 17 15 146 43 195 46 47.3 11 1.80 0 1000 137 7.7 138.0 61.0 0.30 0.000 0.010 ID ID 5.90 0.413 ID

80th 354 76 56 26 36 20 221 67 357 70 80.5 13 4.10 1 2085 290 8.1 206.5 65.0 0.42 0.033 0.080 ID ID 8.50 1.022 ID

20 - Lower Warrego

20th 68 65 5 5 3 5 6 1 34 25 10.0 3 0.00 0 118 21 6.7 80.5 20.5 0.24 0.027 0.003 ID ID 3.35 0.000 ID

50th 225 72 25 12 13 15 165 43 112 48 37.5 8 0.00 0 611 112 7.5 140.0 29.5 0.40 0.170 0.01 ID ID 13.60 0.054 ID

80th 5293 90 535 20 539 17 250 65 8622 85 2081.0 18 1.17 0 18550 3453 7.7 227.5 50.5 0.71 0.315 0.094 ID ID 34.40 0.254 ID

20 - Lower Warrego near stream

20th 68 65 5 5 3 5 6 1 34 25 10.0 3 0.00 0 118 21 6.7 80.5 20.5 0.24 0.027 0.003 ID ID 3.35 0.000 ID

50th 225 72 25 12 13 15 165 43 112 48 37.5 8 0.00 0 611 112 7.5 140.0 29.5 0.40 0.170 0.01 ID ID 13.60 0.054 ID

80th 5293 90 535 20 539 17 250 65 8622 85 2081.0 18 1.17 0 18550 3453 7.7 227.5 50.5 0.71 0.315 0.094 ID ID 34.40 0.254 ID

21 - Paroo Insufficient data

22 - Bulloo Insufficient data

Fractured rock

1 - Upper Condamine Basalts

20th 50 18 22 10 21 21 317 57 49 16 0.0 0 0.00 0 687 151 7.6 263.5 23.0 0.10 0.000 0.000 0.005 0.000 1.00 0.000 0.000

50th 76 27 47 20 70 48 513 71 99 26 3.3 1 3.55 0 1040 417 7.9 426.0 35.0 0.20 0.020 0.010 0.020 0.010 1.50 0.543 0.000

80th 114 62 72 28 115 60 651 82 205 40 9.6 2 25.00 3 1493 635 8.3 540.0 45.1 0.30 0.100 0.010 0.065 0.035 4.76 5.000 0.087

2 - Toowoomba Region Basalts

20th 66 22 16 10 7 8 180 32 88 32 3.4 1 0.50 0 660 85 7.5 150.0 20.0 0.10 0.000 0.000 0.005 0.010 1.30 0.087 0.000

50th 97 35 52 21 59 40 350 49 184 47 10.0 2 5.00 1 1200 390 7.9 291.0 34.0 0.20 0.020 0.010 0.005 0.015 2.20 1.054 0.000

80th 147 79 100 29 116 53 530 64 356 63 22.0 4 33.00 4 1750 708 8.2 443.0 47.0 0.30 0.050 0.020 0.025 0.015 6.20 7.391 0.000

3 - Lower Condamine Basalts

20th 92 34 18 9 14 11 257 30 100 30 6.0 1 0.10 0 790 114 7.6 220.0 30.0 0.20 0.000 0.000 0.000 0.000 2.10 0.000 0.000

50th 158 49 55 19 56 30 445 49 220 47 14.4 2 1.00 0 1400 380 7.9 376.0 48.0 0.30 0.010 0.010 0.003 0.018 3.80 0.130 0.000

80th 308 79 105 28 102 42 592 66 596 67 35.6 5 16.90 1 2568 643 8.3 494.5 60.0 0.50 0.050 0.020 0.040 0.030 8.19 3.793 0.000

51



4 - Eastern Basement With Basalt Remnants

20th 157 46 10 3 4 3 361 25 102 25 11.6 2 0.00 0 1033 49 8.0 308.1 18.0 0.10 0.000 0.000 0.010 0.010 3.68 0.000 0.005

50th 225 68 32 7 52 21 519 50 275 44 30.0 4 0.30 0 1500 331 8.3 431.5 25.0 0.29 0.010 0.010 0.010 0.010 9.65 0.065 0.033

80th 668 93 109 18 129 39 719 71 933 67 130.5 8 3.33 0 2922 750 8.5 596.3 55.7 0.41 0.138 0.070 0.027 0.023 20.76 0.724 0.082

5 - Main Range Volcanics

20th 72 30 15 6 13 12 302 48 35 12 4.0 1 0.40 0 688 104 7.5 247.5 25.0 0.12 0.000 0.000 0.005 0.001 1.69 0.087 0.000

50th 122 46 38 15 44 33 460 72 80 23 12.0 3 2.55 0 1032 291 8.0 383.0 45.0 0.26 0.020 0.010 0.010 0.005 3.20 0.554 0.082

80th 237 78 68 28 80 44 602 85 245 43 45.9 7 20.12 2 1866 489 8.3 500.0 61.0 0.49 0.050 0.020 0.040 0.015 9.04 4.374 0.082

6 - Border Rivers Headwaters

20th 75 42 17 9 13 16 164 19 92 42 9.1 2 0.00 0 648 104 7.0 138.8 20.1 0.20 0.000 0.000 0.007 0.003 2.60 0.000 ID

50th 189 57 67 20 45 22 351 37 305 56 36.0 6 1.00 0 1550 366 7.7 294.5 30.0 0.33 0.010 0.020 0.039 0.015 4.40 0.109 ID

80th 437 70 127 27 115 30 602 51 1033 72 145.2 11 9.10 1 4212 772 8.2 497.1 39.9 0.59 0.093 0.086 0.097 0.019 7.84 0.652 ID

7 - Glenlyon

20th 26 32 11 22 6 20 65 30 15 16 4.2 3 0.45 0 230 50 7.0 50.5 33.6 0.20 0.005 0.000 0.005 0.000 1.27 0.000 ID

50th 117 43 113 35 57 25 345 46 109 25 220.0 32 2.40 0 2014 498 7.4 119.5 37 0.23 0.041 0.01 0.01 0.015 2.39 0.272 ID

80th 191 60 159 37 69 29 568 67 174 43 330.5 50 9.35 6 2125 723 8.0 445.5 42.2 0.52 0.130 0.085 0.058 0.015 2.86 0.950 ID

8 - New England Granite

20th 32 44 6 10 3 9 20 5 30 34 3.2 1 0.21 0 273 45 6.6 16.0 33.9 0.20 0.003 0.010 0.030 0.010 1.80 0.034 ID

50th 65 64 23 18 9 14 74 37 78 51 12.0 4 1.00 0 600 106 7.1 60.5 52.0 1.36 0.010 0.110 0.925 0.015 3.10 0.217 ID

80th 173 78 48 39 25 21 175 53 321 85 25.4 11 13.30 4 1225 244 7.7 146.0 65.7 3.00 0.125 0.663 2.583 0.043 6.12 4.489 ID

Sediments overlying the GAB

1 - Weathered Alluvium

20th 168 67 13 5 8 7 73 1 144 47 36.3 6 0.00 0 624 71 7.0 78.6 45.0 0.13 0.000 0.000 0.008 0.000 8.10 0.000 0.000

50th 666 76 82 10 73 13 197 10 982 77 281.7 12 2.40 0 2690 569 7.6 199.7 57.0 0.40 0.000 0.010 0.050 0.015 19.45 0.011 0.000

80th 4418 87 592 15 550 19 384 40 8590 86 1600.0 16 12.50 0 22710 3706 7.9 333.3 80.0 0.80 0.120 0.184 0.190 0.035 30.10 2.717 0.000

1 - Weathered Alluvium near stream

20th 104 63 7 4 4 2 156 5 75 33 15.1 5 0.00 0 525 27 7.2 134.6 18.3 0.15 0.000 0.000 0.017 0.000 4.65 0.130 ID

50th 289 74 24 10 10 13 256 49 180 40 76.0 11 2.40 0 1269 102 7.7 210.0 70.0 0.30 0.000 0.010 0.040 0.015 11.50 1.930 ID

80th 1368 92 170 22 149 20 388 58 2398 83 504.5 15 7.20 1 6400 1000 8.3 321.0 86.0 0.52 0.044 0.043 0.210 0.017 28.32 0.000 ID

2 - Sand Dunes Insufficient data

3 - Tertiary Sediments

20th 395 81 3 1 0 0 0 4 195 34 0.0 0 ID ID 0 9 ID 136.1 ID ID ID ID ID ID ID ID ID



Upper GAB

1 - Winton Mackunda Western

20th 332 77 22 5 10 2 0 3 400 63 8.6 0 0.00 0 0 104 7.2 107.0 18.0 0.14 0.000 0.010 0.011 0.000 11.60 0.000 ID

50th 864 85 64 7 27 6 0 9 1301 77 128.7 9 2.15 0 0 262 7.7 179.5 20.5 0.40 0.010 0.025 0.030 0.015 23.69 0.467 ID

80th 1828 93 185 12 95 12 172 23 2997 93 449.5 17 8.00 1 3892 876 8.2 282.9 43.7 0.66 0.065 0.160 0.100 0.285 36.29 1.739 ID

52



2 - Winton Mackunda Central

Insufficient data

3 - Winton Mackunda Eastern

20th 276 74 21 5 13 5 0 4 168 41 20.5 3 0.00 0 0 99 7.4 124.9 16.1 0.15 0.000 0.000 ID ID 11.59 0.000 0.000

50th 1025 83 59 8 40 10 240 15 1260 75 138.0 9 0.50 0 1976 291 7.9 282.5 38.0 0.30 0.000 0.000 ID ID 22.45 0.109 0.000

80th 1584 89 142 11 97 14 534 50 2483 86 410.5 12 7.21 0 7920 715 8.2 518.6 53.0 0.65 0.017 0.100 ID ID 31.55 1.567 0.000

4 - South West Upper Cretaceous Aquitard

Insufficient data

5 - Central Upper Cretaceous Aquitard

20th 240 80 8 2 2 1 120 10 172 49 16.0 2 ID ID 546 27 7.8 153.5 ID 0.31 ID ID ID ID 11.28 ID ID



6 - Probable Upper Cretaceous Aquitard




Main GAB Aquitard

1 - Eastern Wallumbilla Outcrop

20th 440 73 3 1 1 0 53 2 158 23 0.0 0 0.00 0 877 9 7.1 144.9 13.0 0.19 0.000 0.000 0.006 0.000 26.72 0.000 ID

50th 660 96 14 2 6 2 506 31 650 59 9.0 1 0.00 0 2399 53 8.1 567.0 17.0 0.98 0.020 0.040 0.020 0.015 41.59 0.000 ID

80th 3365 99 493 12 344 15 859 75 6238 89 766.2 7 2.25 0 10000 2580 8.5 763.1 50.4 1.73 0.434 1.800 0.107 0.156 62.61 0.489 ID

2 - Wallumbilla Doncaster Outcrop

20th 157 42 10 5 1 2 0 3 197 42 40.7 4 0.00 0 0 34 7.4 106.0 12.0 0.10 0.000 0.000 ID ID 4.88 0.000 ID

50th 279 70 74 19 16 8 82 17 360 56 140.0 17 0.00 0 960 271 7.6 155.0 17.0 0.20 0.000 0.000 ID ID 12.79 0.000 ID

80th 781 93 318 30 173 22 245 31 1631 80 1003.7 34 2.02 0 2200 1471 8.2 230.6 26.0 0.50 0.020 0.365 ID ID 22.76 0.439 ID

3 - Central Surat Mid Cretaceous

20th 454 66 29 6 14 6 90 1 351 47 44.2 5 0.00 0 3151 146 6.8 100.2 35.5 0.08 0.000 0.000 0.005 0.001 15.85 0.000 0.000

50th 2010 76 256 10 169 13 253 4 3282 84 464.8 10 1.25 0 24000 1322 7.5 221.5 56.0 0.21 0.005 0.020 0.030 0.015 26.05 0.272 0.000

80th 6065 88 1108 14 1007 20 453 41 12646 90 1879.0 13 12.50 0 50690 6833 8.0 372.9 78.5 0.44 0.030 1.753 0.129 0.050 36.54 2.717 0.000

4 - Wallum Nebine Unproductive Area

20th 292 73 7 3 2 1 124 6 180 38 34.0 4 0.00 0 1110 23 7.6 138.8 14.7 0.20 0.000 0.000 ID ID 11.59 0.000 0.000

50th 333 92 18 5 7 4 247 25 291 52 175.5 16 0.50 0 1500 69 8.2 218.5 17.0 0.36 0.010 0.010 ID ID 19.51 0.109 0.000

80th 691 97 143 15 68 11 383 49 978 74 289.5 31 1.65 0 3165 618 8.4 328.8 22.0 0.69 0.030 0.020 ID ID 29.38 0.359 0.000

5 - Coreena and Doncaster Nebine Ridge

20th 270 87 5 2 1 1 161 8 112 34 0.0 0 0.00 0 998 19 7.8 169.8 17.0 0.39 0.000 0.000 0.005 0.000 22.57 0.000 ID

50th 485 94 18 3 7 2 325 24 617 72 2.0 0 0.63 0 1950 72 8.2 300.0 19.0 0.55 0.010 0.010 0.010 0.010 28.84 0.136 ID

80th 997 97 76 7 45 6 495 65 1553 91 25.9 2 2.59 0 4300 346 8.5 430.0 20.0 0.92 0.050 0.020 0.020 0.015 34.32 0.563 ID

20th 203 95 2 1 0 0 264 40 57 16 0.0 0 0.00 0 760 9 8.0 304.5 17.0 0.51 0.000 0.000 0.000 0.000 23.10 0.000 0.000

53



6 - Southern Wallumbilla Fresh Zone

50th 230 97 4 2 1 1 432 76 80 23 0.0 0 0.00 0 900 14 8.3 371.0 20.0 0.84 0.020 0.010 0.000 0.000 28.20 0.000 0.000

80th 402 98 14 3 4 2 506 83 372 53 2.0 0 1.00 0 1362 70 8.5 440.0 23.9 2.08 0.091 0.020 0.010 0.015 38.75 0.217 0.002

7 - South Western Eromanga Saline Zone

20th 375 75 23 4 6 1 0 2 400 63 30.5 2 0.00 0 0 107 7.0 98.0 19.0 0.30 0.000 0.016 ID ID 11.64 0.000 ID

50th 713 88 57 8 14 3 98 10 958 74 164.5 12 2.10 0 0 208 7.6 156.5 22.0 0.60 0.005 0.050 ID ID 22.82 0.457 ID

80th 1270 94 152 15 40 10 253 23 2233 90 383.8 20 8.50 0 4400 579 8.0 288.9 31.5 0.93 0.105 0.069 ID ID 33.65 1.848 ID

8 - Northern Eromanga Allaru and Toolebuc

20th 309 72 2 1 0 0 0 15 225 34 0.3 0 0.00 0 0 6 7.4 208.1 ID 0.37 ID ID ID ID 9.85 0.000 ID

50th 339 96 10 2 4 2 383 41 242 48 30.0 3 0.38 0 1435 42 7.9 350.5 ID 1.35 ID ID ID ID 34.36 0.082 ID

80th 586 99 71 17 24 5 450 59 891 79 119.2 12 1.80 0 2725 276 8.1 489.1 ID 2.80 ID ID ID ID 55.34 0.391 ID

9 - North Central Coreena

20th 177 67 11 5 4 2 0 3 156 42 28.6 7 0.41 0 0 49 7.2 83.1 19.0 0.20 0.000 0.002 0.015 0.005 6.33 0.089 ID

50th 441 78 54 12 24 9 124 13 615 72 93.0 12 1.40 0 1100 259 7.8 129.0 55.0 0.25 0.010 0.020 0.055 0.015 15.98 0.304 ID

80th 1639 92 202 16 83 18 296 43 2511 85 542.3 18 5.90 0 3366 779 8.1 272.7 63.5 0.54 0.043 0.040 0.175 0.035 30.65 1.283 ID

Mid GAB Aquifers

1 - Northern Maranoa Bungils

20th 210 67 6 2 1 0 0 3 125 34 46.5 6 0.00 0 0 20 7.2 88.0 13.0 0.15 0.000 0.000 0.000 0.000 9.42 0.000 0.000

50th 443 89 28 7 5 2 0 18 443 52 120.1 19 0.50 0 0 122 7.9 191.0 16.0 0.30 0.010 0.010 0.015 0.010 19.57 0.109 0.000

80th 1153 97 205 21 58 12 277 49 1344 75 806.5 38 2.32 0 2050 790 8.4 301.8 20.0 0.80 0.100 0.030 0.050 0.020 32.23 0.504 0.023

2 - Central Mooga and Orallo Outcrops

20th 199 74 3 1 0 0 0 26 102 30 20.0 5 0.00 0 0 10 7.6 237.0 11.0 0.11 0.000 0.000 ID ID 8.99 0.000 0.000

50th 356 93 13 4 4 2 316 46 220 41 75.7 11 0.50 0 1065 55 8.2 334.0 15.5 0.30 0.020 0.010 ID ID 22.41 0.109 0.016

80th 588 99 51 14 21 11 454 64 660 55 228.0 19 2.00 0 2145 213 8.6 454.0 21.1 0.70 0.465 0.060 ID ID 49.29 0.435 0.033

3 - Eastern Cretaceous Outcrop

20th 162 82 4 1 1 0 105 6 85 32 0.5 0 0.05 0 771 14 7.3 100.0 13.7 0.10 0.000 0.000 0.005 0.010 12.49 0.021 0.000

50th 395 93 10 3 4 2 293 30 337 64 8.0 1 0.50 0 1650 47 8.0 263.0 17.0 0.39 0.070 0.010 0.010 0.015 28.30 0.109 0.000

80th 1167 98 74 9 22 7 644 66 1780 89 95.1 6 1.89 0 3870 267 8.5 571.0 33.3 0.65 0.809 0.182 0.110 0.015 49.27 0.285 0.065

4 - Hooray Northern Outcrop

20th 76 48 19 17 6 9 0 15 74 34 29.4 9 0.00 0 0 84 7.3 88.0 21.1 0.10 0.000 0.009 ID ID 2.85 0.000 ID

50th 115 57 42 25 15 16 169 33 156 46 66.0 17 0.00 0 710 185 7.6 168.0 28.5 0.20 0.020 0.010 ID ID 3.87 0.000 ID

80th 263 68 135 34 42 21 251 48 334 56 359.2 32 0.50 0 1650 526 8.1 217.5 34.3 0.40 0.075 0.041 ID ID 4.83 0.109 ID

5 - Lower Balonne Gubberamunda

20th 255 98 2 0 0 0 415 57 88 19 0.0 0 0.00 0 1063 5 8.0 351.8 21.0 0.44 0.000 0.000 0.000 0.014 35.76 0.000 0.000

50th 341 99 2 1 0 0 561 71 130 28 5.0 1 0.25 0 1360 8 8.4 496.0 26.0 0.80 0.010 0.010 0.005 0.015 51.80 0.054 0.000

80th 510 99 4 1 1 1 863 80 260 37 28.8 4 1.00 0 2016 15 8.6 761.1 29.0 1.50 0.213 0.010 0.010 0.020 72.97 0.217 0.000

6 - North Wallumbilla Bungil and Mooga

20th 479 87 5 1 1 0 0 4 353 47 9.2 0 0.00 0 0 20 7.3 142.8 13.0 0.20 0.000 0.000 ID ID 28.41 0.000 0.000

50th 872 96 24 3 6 1 195 13 1170 75 117.0 8 0.50 0 2420 94 8.1 287.0 15.0 0.40 0.025 0.010 ID ID 42.64 0.109 0.016

80th 1865 99 113 7 42 5 443 43 2665 85 583.9 17 3.41 0 6454 437 8.5 462.5 16.0 0.70 0.575 0.040 ID ID 61.76 0.741 0.163

7 - Northern Central Hooray

20th 238 77 3 1 0 0 1 10 150 39 54.0 9 0.00 0 626 10 7.5 117.0 14.5 0.20 0.000 0.000 0.005 0.000 12.83 0.000 0.000

50th 325 96 12 4 2 1 210 33 251 52 101.5 15 0.50 0 1300 41 8.0 208.0 19.0 0.30 0.010 0.010 0.010 0.010 25.20 0.109 0.000

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80th 540 98 57 14 15 6 321 43 699 73 212.6 22 2.63 0 2355 198 8.5 293.0 23.5 0.66 0.100 0.030 0.059 0.020 39.26 0.543 0.000

8 - Northern Surat Thickest Bungil and Mooga

20th 355 98 1 0 0 0 520 56 120 17 0.0 0 0.00 0 1400 5 8.1 495.5 14.0 0.47 0.000 0.000 0.000 0.000 42.74 0.000 0.000

50th 444 99 2 1 1 0 763 74 154 25 1.0 0 0.50 0 1720 11 8.4 680.0 17.0 1.25 0.050 0.005 0.005 0.015 65.35 0.109 0.000

80th 521 99 4 1 1 1 989 82 252 42 24.3 3 0.50 0 2026 16 8.7 874.5 20.0 2.23 0.190 0.010 0.010 0.021 83.91 0.109 0.049

9 - Northern Central Outcrop Area

20th 45 48 11 7 1 1 0 13 46 27 16.6 7 0.00 0 0 39 7.2 67.8 14.0 0.10 0.000 0.001 ID ID 2.27 0.000 ID

50th 225 70 47 22 7 6 73 28 180 45 100.0 20 0.50 0 437 156 7.7 150.0 18.5 0.12 0.010 0.010 ID ID 6.33 0.109 ID

80th 470 91 81 31 18 19 295 59 511 59 238.5 32 1.13 0 1739 278 8.0 283.5 29.9 0.30 0.060 0.282 ID ID 19.28 0.246 ID

10 - South Saline Gubberamunda

20th 216 90 3 2 0 0 156 6 86 28 0.0 0 0.00 0 891 9 7.6 148.3 15.0 0.26 0.000 0.000 0.000 0.003 27.06 0.000 ID

50th 619 95 20 3 6 2 305 18 847 82 0.0 0 0.00 0 2400 77 8.1 255.0 19.0 0.44 0.010 0.010 0.010 0.015 30.29 0.000 ID

80th 1108 98 64 6 20 3 486 72 1758 94 4.0 0 2.17 0 5258 260 8.4 411.9 24.0 0.60 0.030 0.050 0.020 0.020 35.80 0.472 ID

11 – South-east Kumbarilla

20th 315 98 2 0 0 0 459 60 72 13 0.0 0 0.00 0 1173 6 8.0 506.0 13.0 0.55 0.005 0.000 0.000 0.000 38.10 0.000 0.000

50th 417 99 3 1 1 0 720 80 120 19 2.0 0 0.50 0 1600 10 8.4 660.0 15.0 1.50 0.020 0.010 0.005 0.015 56.30 0.109 0.000

80th 530 99 4 1 2 1 969 86 260 39 9.1 1 1.30 0 2050 19 8.6 864.6 19.0 3.20 0.130 0.010 0.017 0.015 71.65 0.283 0.033

12 - Southern Hooray Thinning Area

20th 183 95 2 1 0 0 323 65 59 18 0.0 0 0.00 0 725 6 8.0 290.0 18.0 0.50 0.000 0.000 0.000 0.000 21.58 0.000 0.000

50th 214 98 4 2 1 1 417 77 70 22 0.0 0 0.00 0 862 12 8.3 362.0 21.0 0.60 0.020 0.010 0.005 0.010 28.81 0.000 0.000

80th 275 99 7 3 2 2 490 81 153 34 2.0 0 0.71 0 1030 27 8.5 420.9 23.0 1.57 0.060 0.015 0.010 0.015 35.69 0.154 0.000

13 - Surat Thicker Mooga Saline Area

20th 427 98 3 1 0 0 399 28 250 40 0.0 0 0.00 0 1872 9 8.2 333.5 16.0 1.00 0.004 0.000 ID ID 51.50 0.000 ID

50th 506 99 4 1 0 0 543 43 439 56 3.2 0 0.50 0 2308 11 8.4 491.5 18.0 1.80 0.020 0.010 ID ID 62.58 0.109 ID

80th 572 99 6 1 1 0 675 56 530 59 97.2 7 1.07 0 2565 19 8.6 578.1 21.0 2.08 0.251 0.023 ID ID 71.23 0.233 ID

14 - Western Hooray

20th 171 96 2 1 0 0 313 65 55 16 0.0 0 0.00 0 710 7 8.0 273.7 20.0 0.49 0.000 0.000 0.000 0.000 23.25 0.000 0.000

50th 223 98 3 2 0 0 430 75 74 24 1.0 0 0.00 0 917 10 8.3 372.0 23.0 0.60 0.010 0.010 0.005 0.010 29.59 0.000 0.000

80th 291 99 5 2 1 1 555 83 135 33 8.1 2 1.10 0 1200 18 8.6 473.3 26.0 1.05 0.050 0.010 0.010 0.015 37.21 0.239 0.000

Lower GAB

1 - Central Surat Springbok Area

20th 234 96 2 1 0 0 353 49 80 19 0.5 0 0.00 0 923 6 7.9 321.0 14.0 0.40 0.000 0.000 0.000 0.003 27.60 0.000 0.000

50th 315 99 3 1 1 0 544 71 120 25 10.0 2 0.50 0 1269 12 8.3 475.0 18.0 0.70 0.010 0.005 0.005 0.015 44.64 0.109 0.000

80th 523 99 10 2 4 2 755 79 360 45 33.7 5 1.20 0 1987 38 8.6 668.7 28.1 1.71 0.165 0.015 0.010 0.020 62.11 0.261 0.000

2 - Eastern Springbok Outcrop

20th 243 79 5 1 2 1 198 7 183 41 0.7 0 0.00 0 963 19 7.5 194.3 13.0 0.19 0.005 0.000 0.005 0.001 14.75 0.000 0.000

50th 677 91 20 3 11 4 345 26 737 70 8.0 1 0.70 0 2925 96 8.0 308.5 18.0 0.30 0.050 0.010 0.010 0.015 28.97 0.152 0.000

80th 1830 98 89 10 83 12 838 58 2970 90 47.6 3 2.50 0 9021 612 8.4 795.2 52.1 1.75 0.891 0.097 0.049 0.030 56.49 0.543 0.016

3 - Fresh Hutton South-eastern Outcrop

20th 175 54 25 6 24 10 325 15 231 38 6.9 1 0.10 0 1400 185 7.7 275.4 16.0 0.16 0.000 0.000 ID ID 4.61 0.022 0.000

50th 361 65 59 14 57 22 504 40 412 57 24.8 2 1.50 0 2150 380 8.0 420.0 24.5 0.30 0.010 0.010 ID ID 8.10 0.326 0.000

80th 591 77 124 20 90 28 668 59 957 81 50.1 4 26.50 2 3790 676 8.3 568.0 37.0 0.47 0.059 0.051 ID ID 13.39 5.761 0.029

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4 - North East Walloons

20th 339 61 12 2 6 2 249 7 334 48 4.0 0 0.00 0 1650 58 7.5 230.0 12.0 0.20 0.005 0.005 0.005 0.010 9.05 0.000 0.000

50th 750 82 53 8 41 9 390 20 968 76 35.8 2 1.00 0 3500 308 8.0 344.5 15.0 0.40 0.020 0.020 0.020 0.015 17.69 0.217 0.000

80th 1554 96 155 18 134 21 615 47 2931 91 134.0 6 5.00 0 9015 864 8.4 539.5 27.9 0.80 0.100 0.087 0.043 0.033 48.99 1.087 0.033

5 – North-eastern Hutton Outcrop

20th 416 76 7 1 1 0 63 8 464 67 0.0 0 0.00 0 80 26 7.5 148.7 11.7 0.10 0.000 0.000 0.004 0.000 11.56 0.000 0.000

50th 669 93 24 3 8 2 243 16 894 80 18.3 1 0.50 0 2600 116 7.9 232.0 15.0 0.30 0.020 0.025 0.020 0.010 36.88 0.109 0.000

80th 1265 98 84 9 79 14 523 27 1921 91 86.5 5 3.19 0 5100 533 8.4 485.9 41.2 0.66 0.120 0.110 0.135 0.015 53.82 0.693 0.016

6 - Northern Hutton Outcrop

20th 39 38 20 20 5 3 0 37 40 20 9.3 3 0.00 0 0 91 7.0 134.2 12.0 0.05 0.000 0.000 0.003 0.000 1.63 0.000 ID

50th 78 50 36 31 15 18 213 55 65 33 26.0 7 0.25 0 538 162 8.0 185.0 19.5 0.13 0.000 0.005 0.010 0.005 2.49 0.054 ID

80th 135 69 63 35 27 29 264 71 194 56 64.1 13 0.70 0 910 259 8.3 218.0 36.4 0.30 0.020 0.040 0.025 0.015 7.28 0.152 ID

7 - Northern Walloons

20th 239 91 3 1 1 0 162 8 175 42 0.0 0 0.00 0 854 11 7.9 217.1 12.0 0.20 0.000 0.000 ID ID 23.20 0.000 ID

50th 510 97 9 2 3 1 323 29 580 69 6.0 0 0.60 0 1600 32 8.2 308.0 15.0 0.69 0.000 0.010 ID ID 39.46 0.130 ID

80th 1361 99 56 5 15 2 497 52 2003 91 42.0 4 3.10 0 5145 190 8.6 438.6 20.0 1.30 0.163 0.020 ID ID 64.04 0.674 ID

8 - Saline South-eastern Hutton Outcrop

20th 212 66 19 3 10 3 201 6 262 54 2.7 0 0.00 0 1308 100 7.4 168.3 13.0 0.20 0.000 0.000 0.010 0.000 6.50 0.000 0.000

50th 564 79 54 9 33 12 379 24 760 73 27.0 2 0.50 0 2865 260 7.9 320.0 19.0 0.40 0.010 0.015 0.030 0.010 15.30 0.109 0.000

80th 1475 92 138 18 123 19 629 41 2482 89 151.2 6 4.30 0 7068 706 8.2 520.9 39.0 0.90 0.235 0.108 0.170 0.024 28.67 1.413 0.023

9 - South East Walloons

20th 121 41 9 4 4 3 300 30 101 27 3.4 1 0.00 0 880 45 7.7 250.5 12.0 0.10 0.000 0.000 0.000 0.000 2.90 0.000 0.000

50th 225 72 39 12 27 14 455 52 236 45 13.0 2 1.00 0 1500 222 8.0 390.0 17.0 0.27 0.010 0.010 0.010 0.010 8.10 0.217 0.000

80th 425 93 89 23 89 34 662 71 560 65 46.2 4 6.00 0 2550 566 8.4 562.0 29.5 0.50 0.060 0.020 0.148 0.025 17.89 1.324 0.033

10 – South-eastern Hutton Outcrop

20th 140 41 26 9 14 9 227 15 165 41 8.6 1 0.00 0 1111 142 7.4 190.0 13.0 0.10 0.000 0.000 0.000 0.000 3.14 0.000 0.000

50th 260 58 65 17 48 23 410 34 380 62 20.0 2 0.70 0 1817 391 7.8 346.0 20.0 0.30 0.020 0.010 0.008 0.013 5.88 0.152 0.000

80th 507 77 140 26 145 38 581 56 1053 81 53.7 4 3.66 0 3895 959 8.2 485.0 30.0 0.50 0.090 0.080 0.048 0.020 10.34 0.796 0.031

11 - Southern Limit of Adori

20th 92 66 2 2 0 0 74 19 58 29 7.9 2 0.00 0 461 6 7.7 110.6 15.0 0.10 0.000 0.000 ID ID 4.34 0.000 ID

50th 132 85 18 12 4 3 176 62 80 34 12.9 3 0.50 0 562 61 8.1 180.0 18.5 0.14 0.010 0.010 ID ID 13.39 0.109 ID

80th 288 98 43 25 9 9 221 67 393 70 21.0 7 1.09 0 1333 144 8.6 195.5 22.0 0.21 0.028 0.349 ID ID 24.11 0.237 ID

12 - Hutton Western Eromanga Region

20th 121 94 2 1 0 0 184 58 52 19 1.6 0 0.00 0 597 6 7.9 162.0 22.0 0.25 0.000 0.000 0.000 0.000 13.20 0.000 0.000

50th 177 98 3 2 0 0 311 68 71 29 11.9 4 0.00 0 810 8 8.3 270.0 29.5 0.50 0.010 0.010 0.005 0.010 27.40 0.000 0.000

80th 259 99 6 4 2 3 420 80 105 34 23.7 7 0.50 0 1392 22 8.6 384.0 38.0 1.40 0.050 0.015 0.020 0.015 36.50 0.109 0.000

Basal GAB

1 - Precipice Outcrop

20th 16 27 14 19 6 17 101 64 16 15 4.3 3 0.00 0 247 75 7.0 89.4 11.0 0.10 0.000 0.010 0.000 0.000 0.70 0.000 0.000

50th 23 34 24 35 12 28 136 71 25 22 9.7 6 0.00 0 340 110 7.5 133.0 13.0 0.10 0.010 0.040 0.005 0.015 0.88 0.000 0.000

80th 34 63 38 40 18 36 194 81 35 27 14.0 8 0.50 0 440 157 8.1 189.2 21.2 0.15 0.020 0.070 0.034 0.020 1.88 0.109 0.016

56



2 - Eastern Central Area

20th 87 92 2 1 0 0 150 57 36 17 0.0 0 0.00 0 185 6 7.5 162.2 14.0 0.15 0.000 0.000 ID ID 8.48 0.000 0.000

50th 255 97 3 2 1 1 420 72 99 26 5.0 2 0.25 0 1040 11 8.2 347.0 19.0 0.53 0.008 0.010 ID ID 27.56 0.054 0.000

80th 342 99 8 5 5 4 674 82 165 37 29.6 5 1.00 0 1463 33 8.6 569.6 26.0 2.20 0.180 0.030 ID ID 48.45 0.217 0.016

3 - Northeastern Evergreen Outcrop

20th 299 76 8 1 2 1 175 8 201 28 0.5 0 0.00 0 1295 33 7.3 169.9 14.0 0.30 0.020 0.010 ID ID 10.93 0.000 ID

50th 700 90 20 5 7 2 421 33 656 67 12.0 0 0.80 0 2975 85 7.8 357.0 17.0 0.70 0.070 0.025 ID ID 20.54 0.174 ID

80th 1489 98 113 14 98 9 623 63 1743 89 32.9 3 3.00 0 5505 595 8.3 523.5 20.0 1.55 0.755 0.051 ID ID 60.35 0.652 ID

4 - Southeastern Evergreen

20th 157 60 10 3 5 3 200 14 161 36 1.3 0 0.00 0 920 42 7.4 172.2 14.0 0.20 0.000 0.000 0.005 0.000 5.62 0.000 ID

50th 380 76 40 11 29 13 452 34 480 62 21.0 3 0.50 0 2300 230 7.9 380.0 26.0 0.30 0.010 0.020 0.020 0.008 10.29 0.109 ID

80th 724 94 123 17 89 23 605 62 964 82 70.2 5 3.00 0 3634 675 8.2 532.5 42.0 0.95 0.072 0.187 0.100 0.020 25.88 0.652 ID

5 - Northwestern Evergreen Outcrop

20th 16 31 7 23 6 26 20 27 22 28 6.9 5 0.00 0 149 43 6.3 38.0 11.0 0.09 0.000 0.020 ID ID 0.85 0.000 ID

50th 22 41 13 28 10 31 68 41 35 40 13.0 11 0.05 0 247 81 7.1 65.0 12.0 0.10 0.010 0.040 ID ID 1.18 0.011 ID

80th 53 48 64 41 22 34 177 57 146 54 50.0 22 0.50 0 889 228 7.9 148.7 13.0 0.27 0.038 0.090 ID ID 1.63 0.109 ID

6 - Western Evergreen Only

20th 32 86 2 3 0 0 81 59 16 24 5.0 5 0.00 0 278 8 7.9 83.2 27.0 0.21 0.000 0.005 0.000 0.000 3.10 0.000 ID

50th 104 91 7 7 1 1 177 63 53 29 18.7 8 0.00 0 520 22 8.2 158.0 28.0 0.30 0.030 0.040 0.005 0.010 9.60 0.000 ID

80th 118 97 8 11 2 4 192 67 57 32 21.0 9 0.05 0 543 38 8.5 165.3 32.7 0.53 0.065 0.040 0.017 0.015 19.40 0.011 ID

Earlier Basins Partially Underlying the GAB

1 - Bowen Basin

20th 46 95 2 0 0 0 109 64 9 10 0.0 0 0.00 0 190 5 7.4 91.2 13.0 0.20 0.000 0.000 0.005 0.009 8.38 0.000 0.000

50th 435 98 2 1 0 0 644 81 98 18 0.0 0 0.00 0 1550 7 8.2 564.0 17.0 1.50 0.020 0.010 0.010 0.015 47.22 0.000 0.000

80th 835 99 5 3 1 2 1359 90 225 35 2.6 1 0.50 0 2957 18 8.6 1153.8 22.0 6.73 0.141 0.019 0.031 0.016 109.66 0.109 0.000

2 - Upper Bowen Basin

20th 46 95 2 0 0 0 109 64 9 10 0.0 0 0.00 0 190 5 7.4 91.2 13.0 0.20 0.000 0.000 0.005 0.009 8.38 0.000 0.000

50th 435 98 2 1 0 0 644 81 98 18 0.0 0 0.00 0 1550 7 8.2 564.0 17.0 1.50 0.020 0.010 0.010 0.015 47.22 0.000 0.000

80th 835 99 5 3 1 2 1359 90 225 35 2.6 1 0.50 0 2957 18 8.6 1153.8 22.0 6.73 0.141 0.019 0.031 0.016 109.66 0.109 0.000

2 - Galilee Basin

20th 104 86 3 3 1 1 16 48 30 15 0.0 0 0.63 0 450 13 7.2 179.3 10.0 0.30 ID ID 0.000 0.000 8.78 0.137 ID

50th 124 94 5 4 2 2 253 72 50 27 0.0 0 1.00 0 571 17 8.0 218.0 13.0 0.60 ID ID 0.000 0.000 12.99 0.217 ID

80th 145 95 10 7 4 6 301 84 92 44 8.9 2 2.00 0 1252 44 8.2 250.5 14.3 0.60 ID ID 0.000 0.000 15.05 0.435 ID

Documents

Regional groundwater chemistry zones: Queensland Murray ... · Regional groundwater chemistry zones of the Queensland Murray-Darling Basin – May 2018 i 1. Addendum to March 2017