Part 6 (PDF, 1.9M) - Department of Environment and Heritage

SKARDON RIVER
SHALLOW HYDROGEOLOGY
REPORT
Report Prepared for
GULF ALUMINA LTD
Report Prepared by
SRK Consulting (Australasia) Pty Ltd
Project Number: GUL003
January 2014
SRK Consulting
Page i
SKARDON RIVER
SHALLOW HYDROGEOLOGY REPORT
GULF ALUMINA LTD
Suite 504, Level 5
12 O’Connell Street
Sydney NSW 2000
SRK Consulting (Australasia) Pty Ltd
Level 6, 141 Queen St, Brisbane, Qld 4000
e-mail: [email protected]
website: www.srk.com.au
Tel: +61 7 3054 5000
Fax: +61 7 3054 5001
SRK Project Number GUL003
January 2014
Compiled by
Peer Reviewed by
David Whiting
Principal Hydrogeologist
Ewan Wilson
Principal Mine Water Management
Email: [email protected]]
Author/s:
Adele Ventura; David Whiting
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Table of Contents
Disclaimer.................................................................................................................................................... iv
1 Introduction .................................................................................................................. 1
2 Scope of Works ............................................................................................................ 1
3 Previous Studies .......................................................................................................... 1
4 Geology and Soils ........................................................................................................ 3
4.1
Geology ............................................................................................................................................... 3
4.2
Soils .................................................................................................................................................... 5
5 Hydrogeology Regime ................................................................................................. 6
5.1
Description .......................................................................................................................................... 6
5.2
Shallow Groundwater Levels .............................................................................................................. 7
5.3
Shallow Aquifers in Project Area ......................................................................................................... 8
5.4
Bore Data ............................................................................................................................................ 9
5.5
Groundwater Quality ......................................................................................................................... 12
6 Potential Impacts to Groundwater Regime .............................................................. 13
6.1
Introduction ....................................................................................................................................... 13
6.2
Mining ................................................................................................................................................ 13
6.3
Water Storage and Supply ................................................................................................................ 14
6.4
Significant Wetlands.......................................................................................................................... 14
6.5
Landfill, Sewerage Facility, and Chemical Containment Facilities ................................................... 15
7 Shallow Groundwater Monitoring Plan..................................................................... 15
7.1
Introduction ....................................................................................................................................... 15
7.2
Monitoring Bore Location Plan .......................................................................................................... 15
7.3
Rationale of Monitoring Bore Locations ............................................................................................ 17
7.4
Monitoring Methods........................................................................................................................... 19
7.4.1
Groundwater Levels .............................................................................................................. 19
7.4.2
Groundwater Quality ............................................................................................................. 19
8 Reporting .................................................................................................................... 20
9 Conclusions ................................................................................................................ 20
10 Recommendations ..................................................................................................... 21
11 References .................................................................................................................. 22
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List of Tables
Table 5-1:
Existing Bores in the Skardon River Area .................................................................................. 10
Table 5-2:
Range of Values for Key Parameters Monitored in Skardon River Project bores ..................... 12
Table 7-1:
Shallow Bore Monitoring Plan .................................................................................................... 16
Table 7-2:
Rationale of Monitoring Bore Network for Gulf Alumina Operations ......................................... 18
Table 7-3:
Immediate Bores to be Equipped with Water Level Instrumentation ......................................... 19
List of Figures
Figure 4-1:
Geological Cross-Section Locations ............................................................................................ 4
Figure 4-2:
Geological Cross Section East – West through Bigfoot Swamp.................................................. 5
Figure 4-3:
Geological Cross-Section North-East to South West through Lunnette Swamp ......................... 5
Figure 5-1:
Skardon River Groundwater Contours ......................................................................................... 8
List of Appendices
Appendix A: Shallow Groundwater Bore Monitoring Plan
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Disclaimer
The opinions expressed in this Report have been based on the information supplied to SRK
Consulting (Australasia) Pty Ltd (SRK) by Gulf Alumina Ltd (GA). The opinions in this Report are
provided in response to a specific request from GA to do so. SRK has exercised all due care in
reviewing the supplied information. Whilst SRK has compared key supplied data with expected
values, the accuracy of the results and conclusions from the review are entirely reliant on the
accuracy and completeness of the supplied data. SRK does not accept responsibility for any errors
or omissions in the supplied information and does not accept any consequential liability arising from
commercial decisions or actions resulting from them. Opinions presented in this Report apply to the
site conditions and features as they existed at the time of SRK’s investigations, and those
reasonably foreseeable. These opinions do not necessarily apply to conditions and features that
may arise after the date of this Report, about which SRK had no prior knowledge nor had the
opportunity to evaluate.
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1
Page 1
Introduction
The Skardon River Bauxite Mining Project is located between Skardon River and Namaleta Creek on
Cape York and the mining leases held by Gulf Alumina Ltd comprise a bauxite resource of about 30
million tonnes. The project life is expected to be 10 to 15 years and bauxite, at this stage, will not be
processed by beneficiation. It is envisaged that bauxite mining would commences in the second year
after approval, with construction taking place in the first year. Skardon River Kaolin Pty Ltd
previously conducted kaolin mining and processing operations at Skardon River Mine and there
remains supporting infrastructure, such as the kaolin pits, wet and dry plant, roads and groundwater
monitoring/supply infrastructure within Gulf Alumina leases,.
Gulf Alumina intends to progress with studies to further characterise the shallow hydrogeology of the
Skardon River project area so as to assess future impacts from mining bauxite on shallow aquifers
or important wetlands. An important component of this study is to review historic groundwater
investigation reporting and bore data used in association with the kaolin mine infrastructure within
the Skardon River project site which will provide the basis for hydrogeological interpretation. Gulf
Alumina has commenced monitoring for baseline conditions with the installation of automated water
level loggers in eight (8) bores across the area
An important objective is the development of a regional shallow groundwater monitoring plan which
includes a network of bores for monitoring water levels and water quality to provide data for
characterising baseline conditions across the region prior to mining.
This hydrogeology report is to support the submitting of environmental management plans to the
Queensland Department and Heritage Protection and GA requested amendment of Environmental
Authority (EA) No. MIN104486212.
2
Scope of Works
The scope of works includes the following:-
3
•
Review previous site bore data and studies for characterisation of geology, groundwater levels
and quality of the shallow hydrogeology.
•
Assess potential impacts from bauxite mining and other project related activities on shallow
aquifers and important wetlands.
•
Develop a plan for regional bore monitoring which encompasses the project area, and
•
Compile the information within a report.
Previous Studies
Previous groundwater investigations have been undertaken to characterise conceptual
hydrogeology, groundwater resources for water supply to the kaolin mine in the project area and to
address potential impacts from groundwater abstraction and dewatering of kaolin pits on ingress of
salt water in the shallow aquifers. These studies took place between 1994 and 1998 by Rockwater
Pty Ltd, Golder Associates Pty Ltd and Douglas and Partners Pty Ltd. A list of relevant studies with
findings relevant to hydrogeology and groundwater resources are provided as follows:•
DMW/EW/HP
Hydrogeology Evaluation for Water Supply and Dewatering (Rockwater January 1994), Desktop
study of groundwater resources and results of preliminary drilling programme of sand aquifer
palaeochannel along Namaleta Creek. Conducted some pump out tests on 3 bores (W2, W6
and W11) and pump in tests on 7 bores (W6 to W12), to obtain hydraulic properties and
numerically modelled water supply capability from the palaeochannel sand aquifer. Expected
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from pumping of the aquifer that salt-fresh water interface would migrate eastwards in the
palaeochannel aquifer
•
“Skardon Kaolin Deposit - Results of Phase 2 Groundwater Investigations and Cost Estimates”
(Rockwater, June 1994). Groundwater exploration was carried out in Namaleta Ck and near
Skardon River. Pumping tests were undertaken on two test bores (W13 and W18) and constant
head on one bore (W17) in Namaleta sand aquifer. The tests indicated sustainable yields of 60
3
– 80 m /d (0.7 – 0.95 L/s) from the bores. Bore W13 water quality at end of pumping test was
low salinity at 25 mg/L TDS. Rockwater concluded from their investigations that a resource of
1,100 kL/day from Namaleta sand aquifer was feasible. At the Dry Plant site adjacent to
Skardon River, a deep water exploration hole was drilled to 126 m depth, approximately 400 m
from Skardon River landing and intersected Tertiary laterite and lateritic clay to 15 m depth
overlying carbonaceous shale and siltstone of the Rollings Down Group. However, six geotech
holes drilled at the Dry Plant footprint near Skardon River intersected shallow, saturated sands
and lateritic gravels. A test production bore (W18) at Dry Plant site was pumped for 20 hours at a
3
constant rate of 66 m /day (0.75 L/s) and results indicated the bore can sustain this rate. Water
salinity from bore W18 following pumping indicated salinity of 550 mg/L TDS.
•
Report on Groundwater Feasibility Assessment for proposed Skardon River Kaolin Mine, Nth
Qld (Douglas and Partners (February 1995). Provides a desktop study review of the project
hydrogeology and assessment of groundwater supply options with recommendation for installing
artesian bore within the Mesozoic Sandstone to supply water to the Kaolin mine.
•
Water Supply Investigations for the Skardon River Project Volume 1 and 2 (Golder Associates,
December 1998) prepared for Australian Kaolin Ltd, report 98640106-C. Between July and
August 1998 water supply drilling and testing investigation were undertaken, predominantly in
the Namaleta and Lunette channel fill deposits, but also in the vicinity of the dry plant location
near Skardon River. Hydrogeological conceptual models for the Namaleta and Lunette aquifer
systems were developed.
The extensive drilling campaign included the completion of 29 monitoring bores and 12 production
bores. Several of these bores have been monitored for water levels and quality during the kaolin
mine operations until it was closed in 2011. Ten production bores were completed in the narrow
sand aquifers of the Namaleta and Lunette channel fill deposits considered to be palaeochannels.
The bores were test pumped, analysed for hydraulic properties and water quality, and simple
analytical models applying Winflow software were used for each system to assess impacts from
pumping and estimate likely maximum production rates the aquifer may sustain for various
production periods. The recommended pumping rates ranged from 155 to 225 kL/day (1.8 – 2.6 L/s)
from each of the bores. One of these bores within the Lunnete aquifer (AKP01) was used as camp
water supply for Kaolin operations. At the Skardon River dry plant site two production bores were
installed in a shallow aquifer composed of clayey gravel. These bores were test pumped at about 90
kL/day (1 L/s).
Monitoring bores were installed for water quality monitoring around the effluent disposal facility (3
bores) and at the landfill site (3 bores), and along Namaleta Creek to monitor saltwater interface and
water levels.
In 2011, SRK developed a simple shallow groundwater numerical model across the region using
Modflow package and calibrating it with existing groundwater levels from bores and topographical,
river and sea level data to present indicative shallow groundwater contours and flow behaviour
across the area. These groundwater plans were presented within the Draft Environmental
Management Plan for Gulf Alumina (December 2011). The groundwater modelling indicated that
shallow aquifer recharge is likely to be in the range of 25 – 30% of rainfall in the area.
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Exploration drilling to characterise kaolin deposits within valley fill channel deposits, such as
Namaleta and Lunette Creek systems provide geological data of these systems.
•
Assessment of Exploration Drilling Lunette Creek Area (Saunders, April 1993), Small exploration
drilling programme along Lunette Creek to assess kaolin occurrence, included one hole within
Lunette Swamp and five holes along Lunette Creek to the northwest. The drilling proved
kaoliniitc fluvial sediments possibly filling a paleochannel in a manner to Namaleta Creek kaolin
deposit. Fluvial sediments ranged from 4 to 9 m thick and comprised mainly clay with minor thin
sand bands and nodular ironstone.
Other data sources which may provide further information, but were not available during this review
include:
•
Interim Report #1, Water Supply Availability Review, Skardon River Project, (Golder Associates,
April 1998). Provides a desktop review of previous data and studies and detailed appraisal of
deep artesian aquifer potential for water supply
•
Report on Geotechnical Investigations, Skardon River Kaolin Project (Geotech North, January
1994). Provides assessment from preliminary geotech investigations of kaolin mine, Wet Plant
and Dry Plant areas
4
Geology and Soils
4.1
Geology
The bauxite deposit is located on a part of the Weipa Plateau at 10 – 20 m AHD, and is partly
dissected by drainage channels and consists of deeply weathered profile of bauxite, ferricrete and
clay capping the Bulimba Formation (Douglas and Partners). Exploration drilling near Skardon River
landing has indicated that the Bulimba Formation extends to about 17m depth and below this is
shales and mudstones of the Rolling Downs Formation. The nearest bores drilled intersecting the
Mesozoic Sandstones are Comalco’s oil and gas test wells, “Pennefather Bore” and “Rum Bottle
Bore” drilled in 1991 located south of Mapoon near Wenlock River. A review of seismic data and
borelogs indicates that the Rolling Downs Group extends to 530 to 600 m depth and is underlain by
about 100m of Mesozoic Sandstone (Douglas and Partners, 1995).
The underlying sedimentary sequence listed from oldest to youngest is:
•
Rolling Downs Group. Comprising mainly of clays of marine origin (Mesozoic)
•
Bulimba Formation. Comprising sands and clayey sands (Tertiary)
•
Valley Fill Deposits. Comprising sands, silty sands and clays (Pleistocene and Quaternary).
Two conceptual geological cross-sections have been developed across the project area (Gulf
Alumina, 2011) and a plan showing the alignment of these cross-sections is presented in Figure 4-1.
The sections include an east-west alignment across Bigfoot Swamp (Figure 4-2) and a north-eastsouth alignment across Lunette Swamp and Lunette Creek (Figure 4-3).
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Figure 4-1:
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Geological Cross-Section Locations
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4.2
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Figure 4-2:
Geological Cross Section East – West through Bigfoot Swamp
Figure 4-3:
Geological Cross-Section North-East to South West through Lunnette Swamp
Soils
There are two main land types in the mining area which comprise a) bauxite plateau with bauxite and
lateritic subsoil; and b) low lying seasonally flooded clay soil areas comprising kaolin. The soil type of
the bauxite plateau is well drained Red Kandosol which has thin loamy topsoil underlain by 1 to 6 m
thick pisolitic bauxite, underlain by ironstone.
There are smaller areas of Yellow Kandosols and Yellow Kandosol acid soils in areas of lesser
drainage and on lower slopes fringing drainage lines.
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5
Hydrogeology Regime
5.1
Description
The underlying sedimentary sequence with characterisation of aquifer resources within the Skardon
Project Area listed from oldest to youngest are as follows:
•
Gilbert River Formation and underlying Helby and Garraway Beds of the GAB – Mesozoic
sandstone interbedded with siltstone and conglomerate units - host to the artesian aquifer.
Outcrop and recharged to the east and north-east of Skardon River in vicinity of the Great
Dividing Range. The beds dip gently to the west. Yields from artesian bores within the
sandstones are generally high ranging up to 80 L/s at Aurukun borefield with the aquifer units at
700 – 1000 m below ground level. Generally water is fresh in unconfined outcrop areas and can
deteriorate to brackish conditions down dip at deep confined depths.
•
Rolling Downs Formation – mainly composed of marine argillaceous sediments comprising
fine grained clastics, mudstones and some hydraulically unconnected sandstone lenses,
possibly Mesozoic age. In the Skardon River area the upper part of the unit is laterised and has
a strongly kaolinitic pallid zone. It is generally regarded as an aquitard. Groundwater supplies
from this unit are generally less than 0.5 L/s and water quality is generally brackish to saline.
•
Bulimba Formation (Wyaaba Beds) – comprises variability of lithologies reflecting a range of
alluvial depositional environments. The lithology of Bulimba Formation ranges from claystone
(often kaolinitic) to coarse grained unconsolidated sands, or cemented cobble conglomerate.
Bauxite laterite develops at the top of the Bulimba Formation.
The variability of lithology provides difficulty in finding groundwater resources through drilling.
Sandy intervals within the Bulimba Formation range from less than 1 m to greater than 15 m
thickness. Locally there are sandy, permeable deposits of ancient stream channels. The
northern extremity of these units is north of Skardon River. Shallow aquifers in the Bulimba
Formation consist mostly of coarse grained sand beds Recharge is direct through rainfall and is
relatively fast. This unit is most significant for providing water supply to communities, stations
and industrial mining usage at Weipa on Cape York. Yields from bores installed in the Bulimba
Formation are highly variable but can be up to 30 L/s depending on aquifer properties. At
Mapoon, 15 – 20 km to the south-west, bores penetrating Bulimba sandstone at depths down to
30 m produced yields of about 2 to 5 L/s. The water quality is generally fresh.
•
Valley Cut and Fill Deposits occur within drainage valleys and estuarine areas. The valleys
containing these deposits are incised within the Bulimba or Rolling Downs Group units and
comprise clayey and sandy alluvium channel deposits. The valley deposits are possibly
Pleistocene in age and contain shallow thin sand aquifers. The Namaleta and Lunette sand
aquifers are considered to be meandering palaeochannels within these valley systems and have
been investigated for water supply purposes for the kaolin mine in the 1990’s by Rockwater,
Douglas and Partners and Golder Associates. The alluvium can be very kaolinitic as a result of
source material from the pallid zone of Rolling Downs Group or Bulimba Formation. Yields from
pumping investigations have indicated a range of about 0.5 to 3 L/s from the sand aquifers and
water quality is fresh at TDS less than 105 mg/L.
There is identified a shallow unconfined aquifer system within clayey gravel and sand adjacent to
Skardon River estuarine area in vicinity of Skardon River landing (vicinity of kaolin dry plant).
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•
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Surficial Beach Sand Deposits The beach ridge sands are generally of limited areal extent and
thickness, resting on marine muds and clays. They are directly recharged by rainfall infiltration
and are likely to drain rapidly in dry season. Possibly Pleistocene and Quaternary age. Yields
from these thin aquifers are expected to be limited.
The geological cross-sections (refer to Figure 4-1) will be updated into conceptual hydrogeological
sections using hydrogeological data collected from proposed monitoring bores and existing Cape
Alumina bore data (refer to groundwater plan in Section 7). The Bigfoot Swamp section will
incorporate hydrogeological data from proposed bores MB3, MB4, MB5 and MB6 and Gulf Alumina
bore BH6 MB2 D419. The Lunette Swamp section will incorporate hydrogeological data from
proposed bores MB8, MB9, MB10 and possibly Gulf Alumina bore BH6 MB1 D101.
5.2
Shallow Groundwater Levels
The watertable in the project area generally reflect topography with deeper levels on the bauxite
plateau and shallower levels in the low lying drainage areas. From review of historic groundwater
level data in the Skardon River area the bauxite plateau areas have greater seasonal fluctuation
which may vary between 2 m below ground level (bgl) during the wet to >10 m bgl towards the end
of the dry season. The groundwater levels in the low lying areas near wetlands and drainage
channels are shallow and are typically < 3 m depth.
The watertable contours for the whole Skardon River Area has been generated (Gulf Alumina Ltd,
2011) using a numerical model within the Modflow software package applying a limited bore water
level and surface water body dataset and is presented on Figure 5-1. The model only provided fair
calibration results due to the limited data available at the time of study; and therefore the map should
be used for indicative purposes only.
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Figure 5-1:
5.3
Page 8
Skardon River Groundwater Contours
Shallow Aquifers in Project Area
Shallow aquifers identified from previous investigations at Skardon River Project site include:
•
Namaleta system considered to be a thin shallow palaeochannel sand aquifer in valley fill
deposits and associated with the Namaleta Creek. It comprises fine to coarse predominantly
quartz sand with fining upwards sequence bounded and overlain by kaolin rich clay. From review
of production bore logs AKP02 – AKP05 (Golder, 1998) the aquifer sands were recorded to a
depth of 14 m with thickness of sand to clayey sands ranging from about 4 to 11 m. From
modelled calibration of pumping results (Golder, 1998) the aquifer has an estimated
2
transmissivity of 60 m /day and exhibits leaky aquifer characteristics from overlying and
surrounding sandy clays.
•
Lunette System considered to be a thin shallow palaeochannel sand aquifer in valley fill
deposits. The extent of the palaeochannel has not been confirmed; however it may extend
towards the Lunette Bog and further along Lunette Creek within valley fill sediments towards the
coast. From review of production bore logs AKP01, AKP06 – AKP10 and AKP12 (Golder, 1998)
located south - southeast of Lunette Swamp the aquifer sands were recorded to a depth of 14 m
with thickness of sand to clayey sands ranging from about 3 to 6.5 m. From modelled calibration
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of pumping results (Golder, 1998) the aquifer has an estimated transmissivity of about
2
200 m /day and exhibits leaky aquifer characteristics from overlying and surrounding sandy
clays.
Limited exploration drilling at Lunette Swamp and further to the northwest along Lunette Creek
(Saunders, April 1993) provide an indication that the aquifer system diminishes in size, or may
become absent as indicated in the geological logs showing intersection of thin clayey sandy
horizons generally less than 1.5 m thickness and the underlying basement claystone is shallower
ranging from 5 to 9 m depth.
•
Shallow unconfined alluvial aquifer comprised clayey gravel and sands. From review of
production bore logs AKP10 and AKP11 at the kaolin dry plant site (Golder, 1998) the aquifer
gravels with minor sands were recorded to a depth of 11.5 m with thickness between 4 – 6.5 m
depending on seasonal groundwater levels.
There is potential for other shallow aquifers to occur within sandy lenses in the Bulimba Formation.
5.4
Bore Data
Existing bores in the Skardon River Project region are located on:
•
Gulf Alumina tenements, and
•
Cape Alumina tenements
The existing bores in the Skardon River region with associated tenement holding and historic period
for monitoring dataset during kaolin mine startup and operations is provided in Table 5-1.
As of 11 November 2013, groundwater level monitoring recommenced with a selection of five bores
on Gulf Alumina tenements and three bores on Cape Alumina tenements were fitted with water level
loggers to continuously monitor groundwater levels at 30 minute intervals. These bores are:
Gulf Alumina tenements: - AKP01 (camp supply), AKM26 (Skardon - dry kaolin plant), AKP02
(AKM195) (Namleta Sth), AKM10 (Namleta Nth), and EMB02 (kaolin wet plant); Note that the logger
in AKP01 (camp bore) is also fitted with a salinity (EC) sensor for monitoring; and
Cape Alumina tenements: - BH6 MB1D101, BH6MB2D 419 and BH6MB3D 230.
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Table 5-1:
Bore ID
Existing Bores in the Skardon River Area
Description
Original
purpose
Easting (mE)
Northing (mE)
Mining Lease
monitoring
612844
8689748
ML40069
monitoring
612820
8690055
ML40069
monitoring
614110
8692515
609925
Tenement
Holding
Monitoring
records
(from)
Historic
Monitoring
records (to)
12/08/1998
17/04/2011
AKM04
downgradient of effluent irrigation area kaolin mine operations
downgradient of effluent irrigation area kaolin mine operations
landfill Site - kaolin mine operations
AKM06
saltwater interface near Namleta Ck
monitoring
AKM07
saltwater interface near Namleta Ck
monitoring
609152
8687227
ML6025
GA
12/08/1998
17/04/2011
AKM08
saltwater interface near Namleta Ck
monitoring
609206
8686900
ML6025
GA
12/08/1998
17/04/2011
AKM09
saltwater interface near Namleta Ck
monitoring
609460
8686940
ML6025
GA
12/08/1998
17/04/2011
AKM10
saltwater interface near Namleta Ck
monitoring
609510
8686704
ML6025
GA
12/08/1998
17/04/2011
AKM01
AKM02
#
12/08/1998
17/04/2011
ML40069
Gulf
Alumina
Gulf
Alumina
GA
12/08/1998
17/04/2011
8686500
ML6025
GA
12/08/1998
1/06/2010
AKM11
saltwater interface near Namleta Ck
monitoring
609786
8686760
ML6025
GA
12/08/1998
17/04/2011
AKM19s
Namaleta aquifer
monitoring
609230
8686226
ML6025
GA
12/08/1998
17/04/2011
AKM23
landfill Site - kaolin mine operations
upgradient reference bore of hydrocarbon
storage tanks at Kaolin Dry Plant
Dry plant kaolin operations
monitoring
613798
8690913
ML40069
GA
12/08/1998
22/05/2007
monitoring
609121
8686508
ML40082
GA
12/08/1998
17/04/2011
monitoring
616495
8699400
ML40082
GA
12/08/1998
23/08/2008
AKM27
Dry plant kaolin operations
monitoring
616605
8699400
ML40082
GA
12/08/1998
21/05/2007
AKM28
monitoring
616698
8699657
ML40082
GA
12/08/1998
18/11/2009
production
611810
8687604
ML40082
GA
12/08/1998
?
production
609435
8686325
ML6025
GA
12/08/1998
17/04/2011
production
609543
8685980
ML6025
GA
12/08/1998
17/04/2011
AKP04
Dry plant kaolin operations
Lunette aquifer / approx 1.4 L/s (kaolin
mine camp bore)
Namaleta aquifer -adjacent to kaolin pits
and overburden stockpile areas
Namaleta aquifer -adjacent to kaolin pits
and overburden stockpile areas
Namaleta aquifer
production
609785
8685760
ML6025
GA
12/08/1998
17/04/2011
AKP05
Namaleta aquifer
production
610149
8685618
ML6025
GA
12/08/1998
17/04/2011
AKP10
Dry Plant aquifer gravel – sands
production
616600
8699400
ML40069
GA
12/08/1998
?
AKP11
#
BH6 MB1
D 101
#
BH6 MB2
D 419
#
BH6 MB3
D 230
Dry Plant aquifer gravel – sands
production
616670
8699470
ML40069
GA
12/08/1998
?
regional monitoring bauxite
monitoring
612629
8690559
ML20689
CA
?
?
near Bigfoot Swamp - regional monitoring
bauxite
monitoring
613940
8695676
ML20689
CA
?
?
regional monitoring bauxite
monitoring
615195
8692649
ML20688
CA
?
?
AKM25
#
AKM26
#
AKP01
#
AKP02
AKP03
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Bore ID
BIO 01
EMB01
#
EMB02
EMB03
TMB01
TMB02
Page 11
Description
upgradient reference bore of effluent
irrigation area - Kaolin mine operations
upgradient reference bore of hydrocarbon
storage tanks at Kaolin dry plant
downgradient reference bore of
hydrocarbon storage tanks at Kaolin wet
plant
downgradient reference bore of
hydrocarbon storage tanks at Kaolin wet
plant
upgradient reference bore of open waste
disposal area - Kaolin mine operations
downgradient of open waste disposal
area - Kaolin mine operations
Original
purpose
Easting (mE)
Northing (mE)
Mining Lease
Tenement
Holding
Monitoring
records
(from)
Historic
Monitoring
records (to)
monitoring
612941
8689710
ML40069
GA
31/05/2010
17/04/2011
monitoring
610737
8687122
ML6025
GA
14/01/2006
18/11/2009
monitoring
610467
8686880
ML6025
GA
14/01/2006
18/11/2009
monitoring
616658
8700111
ML40082
GA
12/12/2005
18/11/2009
monitoring
616056
8699611
ML40082
GA
5/11/2002
10/09/2007
monitoring
615997
8699468
ML40082
GA
10/05/2006
17/04/2011
Note: Bores with hashtag and highlighted in bold have been installed with water level loggers since 17/11/2013. These bores were developed to remove
sediment in bore prior to installation of sediment. The logger in camp bore AKP01 also includes salinity (EC) monitoring sensor.
Tenement Holding: GA = Gulf Alumina and CA = Cape Alumina.
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5.5
Page 12
Groundwater Quality
A review of field parameter measurements from monitoring of existing bores in the project area
indicates that the pH of groundwater is slightly acidic ranging from 4.5 to generally less than 5.5.
This is typically the case that pH is generally low on the western part of Cape York The salt content
is variable depending on location, i.e. bores adjacent to Namaleta Creek range from fresh to saline
conditions, while aquifer bores are fresh. A summary of previous sampling results from the kaolin
mine operations is provided in Table 5-2.
The Namaleta and Lunette aquifer systems are similar in chemical composition from water sampling
of production bores (Golder, 1998), although the Namaleta aquifer is slightly higher in sodium and
chloride concentrations. All water quality samples from aquifers have a Total Dissolved Solids of
less than 105 mg/L and are corrosive. Water conveyance will be by polypipe for GA operations due
to issue of corrosion and costs, similar to what occurs at Weipa.
Table 5-2:
Bore
TMB01
TMB02
BIO 01
AKM01
AKM02
AKM04
AKM05
AKM06
AKM07
AKM08
AKM09
AKM10
AKM11
AKM19s
AKM23
AKM25
AKM26
AKM27
AKM28
AKP02
AKP03
AKP04
AKP05
EMB01
EMB03
Range of Values for Key Parameters Monitored in Skardon River Project bores
pH Range
4.1 - 6.0
3.9 - 5.3
na
na
na
3.9 - 5.9
4.6 - 5.1
4.1 - 5.9
4.6 - 5.5
4.0 - 5.2
4.3 - 5.8
4 - 5.8
4.6 - 6.0
4.5 - 5.4
4.6 - 5.3
4.1 - 5.9
4.4 - 5.3
4.6 - 5.3
4.5 - 5.5
4.2 - 5.4
4.3 - 5.1
4.6 - 5.3
4.7 - 5.7
4.1 - 5.3
4.3 - 5.3
EC (uS/cm)
10 - 150
20 - 63
na
na
na
13 - 62
36 - 100
82 - 481
52 - 73
1,518 – 2,310
411 – 10,000
231 – 2,430
673 – 1,230
60.4 - 87
39 - 74
610 – 7,600
97 - 680
670 - 930
230 - 525
50 - 129
32 - 43
33 - 47
39 - 109
38 - 78
3000 – 30,000
Note: COD - Chemical Oxygen Demand; na – not available.
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6
Potential Impacts to Groundwater Regime
6.1
Introduction
Impacts on the groundwater regime from GA bauxite operations without beneficiation are primarily
associated with clearing and mining activities and a subsequent change potentially in the
hydrological regime which may affect sensitive wetlands. Other identified operational activities,
which may impact the groundwater regime are related to drawdown of water storage in kaolin pits
near Namaleta Creek and supply abstraction from the shallow aquifer systems. Also during
operations there maybe localised impacts to groundwater quality hydraulically downgradient from
landfill, sewerage and chemical storage areas.
If GA plan to use beneficiation of bauxite in the future then there will possibly be required greater
extraction demand from the shallow aquifer system to meet bauxite washing needs as a water
supply option. This may invoke further potential environmental impacts associated with drawdown of
water levels and salinity advancement as stated above. Also there would be required a tailing
storage facility and the potential impacts associated with this facility would be a change in
groundwater quality and levels nearby in association with seepage.
None of the areas planned for bauxite mining are identified in zones of potential acid sulphate soils
(PASS) zones although these soil types exist in the region, for example, encountered in the fluvial pit
during kaolin mine operations in 2004. Gulf Alumina has developed a management plan for early
detection and treatment of acid sulphate soil, particularly as precaution for construction in low lying
areas.
Detail of project activities and potential associated impacts are provided as follows:-
6.2
Mining
A change in the hydrological regime from mining and associated land clearing or compaction
disturbance may impact on the site water balance, particularly in association with sensitive wetlands.
Hydrological inputs which may change include baseflow rates due to changes in surface recharge
and changes in runoff rates. Removal of vegetation will reduce evapotranspiration rates, and the
ponding of water in the mine depression will lead to a greater propensity for subsurface recharge
and groundwater table mounding. It therefore maybe expected for the short term following clearing
and mining that recharge will be increased until natural vegetation is re-established on topsoil.
Previous studies at Weipa (Volker and Crees, 1993) have indicated this maybe the case through insitu moisture measurement, hydraulic testing and modelling simulation. Within the postmining
landscape following rehabilitation there is expected to be depressions of a depth of 1 to 3 m depth
depending on the thickness of bauxite removed, which will influence surface drainage and recharge
to an extent on a local scale.
There is a low possibility that mining of bauxite in low lying areas with a shallow water-table may
lead to drawdown of groundwater levels which may influence nearby groundwater dependant
sensitive wetlands, for example, adjacent Lunette Swamp. However, GA intends not to actively mine
when the mine floor is inundated and intentions are no pumping from the bauxite pits so the
likelihood of this impact occurring is remote.
Changes to the surface and groundwater hydrology in the post mining landscape due to excavations,
disturbance and mining equipment compaction which alters recharge and runoff rates. The
excavations of the pits and likely depressed landscape in post-mining rehabilitated areas may result
in seasonal flooding.
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6.3
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Water Storage and Supply
The existing claystone and water pits from previous kaolin mine operation near Namaleta Creek will
be used for storage of operational water. There is a low probability that drawing water levels down
within these pits over an extended period of time may lead to advancement of the saltwater interface
over time from the estuarine salty environment into the Namaleta aquifer. During the previous kaolin
mine operations, there was drawdown of water levels within the fluvial pit (located adjacent
Namaleta Ck) and claystone/water pits with no substantial changes in water salinity detected in
monitoring bores along Namaleta Creek.
The shallow Namaleta aquifer palaeochannel system (and possibly the shallow aquifer at the dry
plant and Lunette palaeochannnel system) is planned to meet supplementary water supply
requirements. In the unlikely event of drawing excessive water from the palaeochannel aquifers
there may potentially lead to the propagation of water level drawdown along the channels which may
influence groundwater dependant ecosystems and changes in water salinity, possibly from drawing
in brackish to salty water from Namaleta creek. These shallow aquifer systems are likely to be
rapidly recharged during wet season rains. Modelling of the Lunette palaeochannel aquifer by
Golder (1998) has predicted that it can sustain a draw of 260 kL/day continuously for seven months
or up to 150 kL/day continuously over nineteen month period, which is greater yield than the
requirements for Camp water supply. Of interest within Golder (1998) report is modelling predictions
have indicated that the Namaleta Aquifer system has lower sustainable production rates than the
Lunette aquifer system and this is due to the lower estimates of transmissivity and leakage within the
Namaleta aquifer system.
6.4
Significant Wetlands
Sensitive groundwater dependant wetlands in the Skardon River area include several swamps
located along drainage lines which may comprise valley fill alluvial deposits with underlying shallow
aquifer systems and also riparian areas adjacent watercourses, such as Namaleta Creek. These
wetlands may be sensitive to changes in the hydrological regime as a consequence of bauxite
mining and associated activities. The changes to the hydrological regime may include baseflow and
runoff volumes, groundwater levels and water quality. The runoff of suspended solids or
contaminants from disturbed areas into sensitive wetland areas is always a visible concern due to
the characteristically high intensity rainfall events that facilitate these processes in this region during
the wet season.
The most significant sensitive wetlands close to mining of bauxite in Gulf Alumina tenements
include:•
Bigfoot Swamp,
•
Lunette Swamp, and
•
Namaleta Creek.
Bigfoot Swamp is located on Cape Alumina tenement ML20689 and is about 600 m west of Gulf
Alumina tenement ML40082. Also Bigfoot Swamp is within a different surface catchment than
tenement ML40082 with the catchment low ridge divide following the NNE – SSW haul road.
Therefore there is unlikely to be impacts from change in baseflow and surface runoff with
entrainment of suspended solids or contaminants entering the swamp.
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Page 15
Gulf Alumina are committed to three buffer protection zones of natural vegetation around wetlands or
riparian areas to minimise impacts from bauxite mining and associated activities and comprise:-
6.5
•
Lunette Swamp - 200 – 250 m buffer from bauxite mining;
•
Namaleta Creek – 100 – 200 m with the shorter buffer accommodating areas already disturbed
by previous kaolin mining
•
Skardon River – 500 m from high tide mark.
Landfill, Sewerage Facility, and Chemical Containment Facilities
During mining operations there is potential for degradation of groundwater quality at landfill and
sewerage facility locations and hydraulically down-gradient from these locations due to groundwater
movement. Also localised degradation of groundwater quality from chemical containment facilities.
7
Shallow Groundwater Monitoring Plan
7.1
Introduction
A groundwater monitoring plan has been developed to capture baseline water level and quality
information across the Project area, in proximity to mining and sensitive wetlands. Existing
monitoring bores associated with the previous kaolin mine operations are incorporated within the
groundwater monitoring plan as well as key Cape Alumina bores located on their tenements. The
monitoring data in association with historic data from kaolin mine operations may be used to develop
background (trigger) levels for discrete parameters to be incorporated into the mining lease
environmental authority conditions, taking into account seasonal or locality variations. This dataset
will be used to monitor the performance of the project once construction and mining is underway,
preferably using the existing monitoring bore network.
7.2
Monitoring Bore Location Plan
A plan showing the location of the bore network for regional monitoring is provided in Appendix A.
and includes 14 bores total. It includes six (6) existing monitoring bores on Gulf Alumina tenements,
three (3) bores on adjoining Cape Alumina tenements and five (5) proposed bores to be drilled on
Gulf Alumina tenements during the dry season. Details of these bores are provided in Table 7-1.
Gulf Alumina has initiated a groundwater monitoring programme since November 2013 with the
installation of water level pressure transducers in eight (8) existing bores across the project area and
includes three (3) bores on Cape Alumina tenements.
An inspection of bores in November 2013 revealed that several existing bores from the kaolin mine
operations are dry or contain limited water in the bore column during the dry season or have
defective bore casing. In the event that these bores are selected in the future for expanding the
groundwater network then they are likely to need replacement. Some of these bores are located
around the kaolin mine facilities, such as, camp effluent disposal and old waste disposal site.
Monitoring of water levels within the kaolin clay pits will be necessary when the project is in
operations to correlate these surface levels with surrounding monitoring bore groundwater levels and
quality, during the period when the pits are actively used for water supply. The depth of these pits is
below the local groundwater table. Opportunistic levels of water levels in pits maybe measured
during the timing of obtaining groundwater levels from regional bores
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Page 16
Table 7-1:
No
Shallow Bore Monitoring Plan
Bore Numbering
1
2
AKM07
AKM10*
3
4
5
6
7
8
AKM26*
AKP01*
AKM195-AKP02*
EMB02*
BH6 MB1 D 101*
BH6 MB2 D 419*
9
10
11
12
13
14
BH6 MB3 D 230*
MB1
MB2
MB3
MB4
MB5
New Site
Name
NA
Namaleta Nth
Skardon
Camp Supply
Namaleta Sth
Wet Plant
Cape 1
Cape 2
Cape 3
NA
NA
NA
NA
NA
GA
GA
Easting
(mE)
(MGA 94)
609152
609510
Northing
(mE)
(MGA 94)
8687227
8686704
GA
GA
GA
GA
CA
CA
616495
611810
609435
610467
612629
613940
CA
GA
GA
GA
GA
GA
615195
608862
611909
614044
614891
615734
Tenement
Holding
Historic
groundwater
levels (mbgl)
Bore Depth
(m bgl)
Screened
interval
(mbgl)
Exist
Exist
0.3 to 4.5
1.2 to 6.3
18
12
6.0 - 12.0
6.0 - 12.0
8699400
8687604
8686325
8686880
8690559
8695676
Exist
Exist
Exist
Exist
Exist
Exist
0.4 to 4.3
5.7
0 to 3.6
4 to 8
?
?
10
14
13.5
15
?
?
4.0 - 10.0
9.0 - 12.0
9.0 - 12.0
?
?
?
8692649
8688531
8688072
8692980
8695396
8695107
Exist
Proposed
Proposed
Proposed
Proposed
Proposed
?
NA
NA
NA
NA
NA
?
nominal 15
nominal 15
nominal 15
nominal 15
nominal 15
?
NA
NA
NA
NA
NA
Drill Status
Bores denoted with asterisk have been fitted with water level pressure transducers for monitoring groundwater levels, and in the instance of AKP01 (Camp Water Supply Bore) also are fitted
with instrumentation to monitor salinity.; NA = Not Available until drilled
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7.3
Page 17
Rationale of Monitoring Bore Locations
The rationale for the number and location of monitoring bores are as follows:a) Provide a broad coverage across the project area so as to assist in regional groundwater level
assessment prior and during project development and operations;
b) Assessment of groundwater levels and quality in proximity to sensitive wetlands such as Lunette
Swamp;
c) Assessment of groundwater level in proximity to bauxite mining areas;
d) Assessment of groundwater levels and quality within/near significant aquifer units such as the
Namaleta Creek and Lunette Creek palaeochannel aquifers, which may be used for water
supply purposes;
e) Provide groundwater level and quality data near water supply clay pits
The rationale for each of the bores is provided in Table 7-2. The number of bores may be revised
following possible changes to project operations in the future, such as beneficiation of bauxite
requiring monitoring bores for a tailings storage facility and changes in water supply demand from
the shallow aquifer. A review during operations of supplementary water supply requirements from
the Namaleta and Lunette aquifers may lead to changes in numbers of monitoring bores in the
vicinity of these aquifers. A review of monitoring data during operations may indicate the need for
additional bores for regional coverage of potential changes from bauxite mining and specific wetland
areas. During operations there will be a need to monitor groundwater quality at specific site facilities
(e.g. landfill, sewerage plant, hydrocarbon storage) and this is covered in the Plan of Operations.
DMW/EW/HP
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Table 7-2:
Page 18
Rationale of Monitoring Bore Network for Gulf Alumina Operations
New Bore
numbering
Rationale
(refer to
points above)
Comment
AKM07
a&c
Regional groundwater level coverage adjacent & downgradient of proposed bauxite
mining (salt water interface)
AKM10
a&c&e
Regional groundwater level coverage adjacent & downgradient of proposed bauxite
mining (salt water interface)
AKM26
a (d)
Regional groundwater level coverage. Maybe used to assess dewatering impacts if
shallow aquifer in vicinity of dry plant is used to supplement water supply needs
AKM195-AKP02
a&d
South side of Namaleta Creek in Namaleta aquifer. Proposed Namaleta aquifer to
supplement water supply
AKP01
a&d
Camp Supply Bore. Monitor potable water salinity and drawdown of water levels
from water supply usage. Also provide regional groundwater levels when bore not
pumping.
EMB02
a&e
Regional groundwater level coverage and adjacent proposed bauxite mining.
Located in vicinity of disused kaolin wet plant.
BH6 MB1 D 101
a
BH6 MB2 D 419
a&b
BH6 MB3 D 230
a
MB1 (proposed)
a&b&c
Near Lunette Swamp in proposed vegetation buffer zone within palaeochannel.
Downgradient from proposed mining and Lunette Aquifer borefield zone to assess
GA operational impacts.
MB2 (proposed)
a&c
Northern section of ML6025 adjacent airstrip and providing regional groundwater
level coverage to adjacent bauxite mining
MB3 (proposed)
a&c
Mid ML40069 and adjacent Haul Rd providing regional groundwater level coverage
to adjacent bauxite mining
MB4 (proposed)
a&c
East of Bigfoot Swamp by approx. 1km, near surface catchment divide adjacent
Haul Rd and providing regional groundwater level coverage adjacent to bauxite
mining.
MB5 (proposed)
a
East of MB4, providing regional groundwater level coverage downgradient from
proposed bauxite mining & near Skardon River tributary wetland
DMW/EW/HP
Regional groundwater level coverage
Regional groundwater level coverage and proximity near Bigfoot Swamp
Between ML40069 and Skardon River tributary. Regional groundwater level
coverage.
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7.4
Page 19
Monitoring Methods
7.4.1 Groundwater Levels
Manual Measurements
Manual readings of standing water levels are measured with a water level dipper at a minimum of
three monthly so as to capture data during the wet and dry seasons and be used for calibration of
automated instrumentation within bores fitted with pressure transducers.
During operations if water is drawn from the Namaleta, Lunette aquifer or shallow aquifer near
Skardon River Landing (kaolin dry plant) for project needs then water level monitoring may be
required frequently from key bores in proximity of the aquifers to assess drawdown.
Automatic Measurements
The equipping in selected bores of automated water level loggers (pressure transducer loggers) will
save on time and costs and provide a series of more frequent water level readings to assess
response to wet seasonal high intensity rainfall events or site activities. Battery life of transducers is
generally about 5 years and is variable to some degree depending on frequency of measurement.
They have a large storage capacity for data points which allows the transducer to operate for years
without exhausting storage capacity, if measurements are set at 0.5 hours or longer timeframes.
It is recommended that data is downloaded from these pressure transducers on a six monthly basis
at beginning and end of wet season, i.e. October – November and April – May. Manual water level
measurements are taken prior to downloading the data from the pressure transducer, such that the
pressure transducer measurements can be calibrated.
Current monitoring bores fitted with water level loggers as of November 2013 are provided in
Table 7-4. These bores were airlifted to remove accumulated sediment and to clean the slotted
section, prior to installing the water level loggers; and includes the three Cape Alumina monitoring
bores. The water level loggers are recording measurements at 30 minute intervals to capture rapid
response during rainfall/storm events.
Table 7-3:
Immediate Bores to be Equipped with Water Level Instrumentation
Bore
Site Name
Reason
AKP01
Camp Supply
Production bore / Lunette channel aquifer / closest to Lunette
Swamp. Also monitors electrical conductivity
EMB01
Wet Plant
Up-gradient of old kaolin wet plant workings.
AKM26
Skardon
Upgradient bore for hydrocarbon storage at Kaolin dry plant.
AKM10
Namaleta Nth
Nth Namaleta Ck
AKM195 (AKP02)
Namaleta Sth
South of Namaleta Ck in palaeochannnel aquifer
BH6 MB1 D 101
Cape 1
NW of camp.
BH6 MB2 D 419
Cape 2
East of Bigfoot swamp
BH6 MB3 D 230
Cape 3
Between ML40069 and Skardon River tributary
7.4.2 Groundwater Quality
Major field water quality parameters such as pH and electrical conductivity measured from
monitoring bores and synchronised with undertaking manual water level readings / downloading of
water level logger data, minimum of six monthly. Frequency of measurements increase to quarterly
during the bauxite operations.
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Page 20
Comprehensive water sampling from a selection of regional monitoring wells to be taken prior to
construction phase of operations, and may include the following suite of analytes:-
8
o
pH (field parameter)
o
Electric conductivity (field parameter)
o
Temperature (field parameter)
o
Major anions
o
Major cations
o
Total Suspended Solids (TSS)
o
Total Dissolved solids (TDS)
o
Total and dissolved aluminium, silica and iron
o
Total metals (Antimony, Cadmium, Chromium, Copper, Iron, Manganese, Mercury, Nickel,
Lead, Aluminium, Selenium)
o
Dissolved metals (Antimony, Cadmium, Chromium, Copper, Iron, Manganese, Mercury,
Nickel, Lead, Aluminium, Selenium).
Reporting
Water level and water quality data is to be entered into Gulf Alumina’s environmental database and
reviewed by personnel to assess if it conforms with Gulf Alumina Water Management Plan and
Environmental Authority conditions.
9
Conclusions
Past investigations and ongoing monitoring for the kaolin mining operations has provided a sound
basis of the groundwater regime with identification of borefields for water supply, groundwater levels
and quality. A total of 14 groundwater monitoring locations are suggested within the regional
groundwater monitoring plan and comprise six (6) existing Gulf Alumina bores, three (3) existing
Cape Alumina bores and an additional proposed drilling of five (5) bore locations.
The installation of automated water level instrumentation with high frequency readings (30 minutes)
in November 2013 within eight (8) of the fourteen (14) bores across the project area will provide
ongoing groundwater level information to characterise baseline conditions, particularly, the change in
the watertable from high rainfall events during the wet season. The additional five (5) monitoring
bore locations have been identified to complement the regional monitoring network for refinement of
groundwater contours and flow pathways and baseline conditions in proximity to bauxite mining and
sensitive wetlands (Lunette Swamp). These bores should also be fitted with automated water level
transducers to monitor groundwater behaviour during the wet and dry seasons.
Gulf Alumina’s intentions during non-beneficiated operations of drawing water from storage in the
kaolin pits is expected to have a low impact on the shallow aquifer regime with respect to drawdown
and change in salinity, based on monitored results from the previous kaolin mine operations. During
Gulf Alumina operations there are several existing monitoring bores in the vicinity of Namaleta Creek
and the palaeochannel system that can be used for monitoring purposes of water levels and quality.
Similarly, if the Namaleta palaeochannel aquifer system is used to supplement supply then existing
bores within the palaeochannel system can be used for monitoring potential impacts of water level
drawdown and quality.
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Page 21
It is envisaged that if bauxite mining commences then it would be in the second year after approval,
with construction taking place in the first year. Additional monitoring bores, where necessary maybe
established in the construction phase and one wet season of data collected prior to mining. Studies
on potential impacts to the hydrological regime from bauxite mining and on sensitive wetlands may
take place using the data (monitoring and drilling) that is obtained from the groundwater monitoring
programme and, where applicable additional, drilling investigations.
10 Recommendations
Conduct a review of this groundwater monitoring plan following installation of the proposed five (5)
monitoring bores and following at least one wet and dry season of data collection. The
hydrogeological data collected from drilling of proposed bores and groundwater monitoring will be
used to update hydrogeological conceptual model and provide baseline conditions, taking into
account seasonal variations for water levels and quality for when project development/operations
commences.
Compile reference water quality database and water levels for baseline conditions and to be used for
the interpretation of bore water quality.
Information collected during installation of the proposed bores should be used to refine the
conceptual hydrogeology, particularly in relation to sensitive wetlands such as Lunette Swamp and
Bigfoot Swamp and characterisation of regional groundwater levels and quality.
Compiled by
David Whiting
Principal Hydrogeologist
Peer Reviewed by
Ewan Wilson
Principal Mine Water Management
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Page 22
11 References
Department of Environment and Resource Management (2010) Monitoring and Sampling Manual
2009 Environmental Protection (Water) Policy 2009. Version 2 September 2010.
Department of Environment and Protection (January 2013) Environmental Authority No.
MIN104486212.
Douglas and Partners Pty Ltd (February 1995) Report on Groundwater Feasibility Assessment,
Proposed Skardon River Kaolin Mine North Queensland, prepared for Venture Exploration NL.
Project No. 21351.
Golder Associates (December 1998) Water Supply Investigations for the Skardon River Project
Volume I and II, prepared for Australian Kaolin Ltd. Report: 98640106-C.
Gulf Alumina Ltd (December 2011), Environmental Management Plan, Skardon River Bauxite Mining
Project.
rd
Qld Environmental Protection Agency (1999) Water Quality Sampling Manual, 3 Edition December
1999.
Rockwater Pty Ltd (January 1994) Hydrogeology Evaluation for Water Supply and Dewatering,
prepared for Skardon Kaolin Project Venture Exploration NL. Report 183.0/94/1 R13/JP.
Rockwater Pty Ltd (June 1994) Results of Phase 2 Groundwater Investigation and Cost Estimate,
prepared for Skardon Kaolin Deposit Venture Exploration NL Signet Engineering. Report
183.0/94/3 VENT005.
Saunders, B (April 1993) Skardon Kaolin Project Assessment of Exploration Drilling Lunette Creek
Area
Volker, R.E. and Crees, M.R. (1993) Recharge estimates for an unconfined aquifer affected by
surface mining and rehabilitation within Hydrology of Warm Humid Regions in Proceedings of
the Yokohama Symposium, July 1993. IAHS Publ. no. 216, 1993.
DMW/EW/HP
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Appendices
Appendices
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Appendix B
Appendix A: Shallow Groundwater Bore Monitoring Plan
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DMW/EW/HP
Appendix B
GUL003_Groundwater_Report_Rev1
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Distribution Record
SRK Report Client Distribution Record
Project Number: GUL003
Report Title: Skardon River Shallow Hydrogeology Report
Date Issued: January 2014
Name/Title
Company
Ian Little
Gull Alumina
Rev No.
Date
Revised By
Revision Details
0
20/12/2013
David Whiting
DRAFT FOR CLIENTS COMMENT
1
30/01/2014
David Whiting
Final to client
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reproduced or transmitted in any form or by any means whatsoever to any person without the written
permission of the copyright holder, SRK.
DMW/EW/HP
GUL003_Groundwater_Report_Rev1
30 January 2014

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