australian groundwater technologiesaustralian groundwater technologies “making water work” •...

“making water work” Australian Groundwater Technologies

“making water work” Australian Groundwater Technologies “making water work” Australian Groundwater Technologies

• Welcome Everybody • Terramin Team:

– Martin Janes - CEO

– Matt Daniel - Environment and Community Superintendent

– Erin Nugent - Commercial Manager

– Eric Whittaker - Principal Geologist

– Ken McBride -Site Supervisor

– Katy Fechner - Environmentalist

• Australian Groundwater Technology: Specialist Consultants

– Jason van den Akker - Hydrogeologist

• Cooe: Environment Consultants

– Joe Misfud

– Angela Dewdney

• Apologies

• Mining history in the area

• Previous water studies and proposals

• Water table characterised by a fractured rock aquifer

– complex systems and typically difficult to distinguish.

• Significant reliance on groundwater in area

• Bores are generally ~100 m deep, with a few being 150 m deep.

• Aside from anecdotal evidence, little is understood about the groundwater system, particularly at depths below 125 m.

Bores target the Brighton

Limestone (marble), (contains the

gold bearing qtz veins)


Key project issue and main focus for research:

1. Quantification of groundwater flows;

2. Groundwater interaction with surrounding aquifers and users;

3. Possible groundwater contamination from historic activities*;

4. Water management options; and

5. Compliance to Water Allocation Plan (WAP).

*Previous work indicated contamination in some drill holes. Follow up

work identified residual drilling fluids and once purged, subsequent

sampling revealed no contamination.


1. Desktop study (review of past studies / other information) (completed)

2. Ongoing collection of information from regional Stakeholders

3. Baseline studies

- Groundwater monitoring (ongoing)

- Bore census (ongoing)

4. Field investigations

- Drilling of five investigation bores (4 completed)

- Pumping (aquifer) testing of investigation bores ( planned July)

5. Development of a robust groundwater model (September –

December)

6. Evaluation of best practice water management options

Regulators for the works are DMITRE and DEWNR.

DMITRE Approvals :

• Construction of five investigation wells. (inc. earth works and water

storage)

• Pump testing of investigation wells.

• Short duration – measures impact between holes

• Risk assessment undertaken with focus on regional impact

• Monitoring of regional bores will be undertaken to measure

effect.

• DMITRE have undertaken multiple site inspections during the drilling

program.


• Groundwater monitoring of 11 site bores commenced in November

is ongoing.

• The groundwater monitoring network expanded off-site to include 12

additional private bores.

• Groundwater level loggers installed in six site monitoring bores and

two private bores identified for equipping. (next week)

• Record groundwater levels four-hourly. (will be 15min during test)

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11/13 12/13 01/14 01/14 02/14 03/14 03/14 04/14 05/14 05/14

De

pth

to

Gro

un

dw

ate

r (m

)

GROUNDWATER LEVEL


Census is ongoing:

• 25 properties

surveyed.

• 46 bores identified

• Water samples

collected from

private bores, dams

and creeks

• 12 private bores are

now being routinely

monitored by

Terramin.

Project Area

Until now little is known about the

aquifers beyond the depth of 125 m.

This drilling program represents the:

• First drilling investigation within

the Inverbrackie Sub-Catchment.

• Most comprehensive study in the

Upper Onkaparinga Catchment

(no investigation bores within 10

km).

NB: A V-notch weir is a specific

dimension 'v notch' in a plate that is

placed so that it obstructs an open

channel flow, causing the water to flow

over the v notch. It is used to meter flow

of water in the channel, by measuring

the head of water over the v notch crest.

V - notch weir to

measure bore yield

• Four investigation wells drilled and cased at

depths ranging from 135 m to 300 m.

• Wells target all geological rock types

(Considered separate aquifers DEWNR).

• Designed to determine the connectivity

between the marble and the adjacent

aquifers.


Information collected during drilling:

• Aquifer yield with depth (to identify major water bearing horizons).

• Groundwater salinity change with depth.

• Fracturing with depth (broken ground). (results forDBIW05)


0

50

100

150

200

250

300

350

0 10 20 30

Bo

re D

ep

th (

m)

Bore yield (L/s)

DWIB3

DWIB1

DWIB4

DWIB5

Depth of old mine workings

Fractured ground

= high groundwater flows

Yield decrease with depth

Private bore yields shown in blue

Investigation bore yields DWIB1, DWIB3, DWIB4,

DWIB5

Brighton Limestone – Host rock of the Gold

deposit. Low yield rock


Information collected during

drilling (continued):

• Geophysical logging

• Acoustic televiewer

• Mapping of fractures

(water bearing zones)

• Detection of thin beds

• Determination of

bedding dip


Aquifer testing to determine the:

• Aquifer parameters (permeability, flows and volumes) required to construct

groundwater model.

• Level of connection between each aquifer i.e. marble/sandstone/siltstone.

• Interaction of faults and structures

• Monitor groundwater drawdown – via site and surrounding private bores.

• Measuring the water quality – EC, pH, Temp, Chemical comp, Turbidity


Airlifting water during drilling of DWIB1

• BH41 (all units)

• DWIB3 (Cox Sandstone)

• BH37 (all units)

• BHR01 (shallow water table)


• Planned during winter – targeting period when minimal

groundwater pumping is likely

• Pumping rates are lower than first anticipated. (25l/s not 45l/s)

• A risk assessment was completed to ensure private water access

will not be impacted during pump test work.

• Developed in consultation with DEWNR, DMITRE and WAP

• Takes into account regional users and water access.

• Site bores and specific private bores will be monitored during the

pump testing.

• Any unforseen impacts detected in private wells will trigger action,

review information, modify plan as appropriate.

Data collected from baseline monitoring, drilling and bore testing will be

used to develop a robust groundwater model.

The model will be used as a tool to:

• Predict groundwater inflows into the mine.

• Assess potential impact to surrounding aquifer / bores.

• Evaluate a range of water management options and mitigation

measures.

• Evaluate the project against the rules and regulations of the WAP.

INJECTION WELLS

MINE WORKINGS

GROUNDWATER DRAWDOWN

NB: Diagram illustrative and not Bird in Hand Gold Model.


Too early to speculate what water management

methods.

The type of water management options will be dictated

by the rate of potential inflows and the nature of the

aquifers

Groundwater modelling ->

•assess feasibility of the project

•determine a range of water management options

Numerous methods and multiple combinations of

mitigation measures.

MAR site: Botanical Gardens


Water management techniques developed in the last 100yrs Progressed from dewatering a region through pumping Management techniques range to suit application • Angas Zinc Mine (SA) – Managed aquifer recharge • Cosmo Gold Mine (NT) – Pre-grout from surface in fractured

rock to stop inflows • Earnest Henry and Mt Margaret Project (QLD) – aquifer

protection for regional users • Rassarden Tin Mine – Tasmania

– Pre-grout to stop water inflow of 12 to 33l/s

• Metropolitan Colliery (NSW) – Sealing cracks to the Waratah Rivulet, protecting aquifer

• Roma (QLD) – MAR treated water to protect irrigators. Trial injection of 10Ml per day. (AGT working with SANTOS)


• Iluka (Balranald) -Trial • Santos – re-injection of CSG co-produced

water - Trial • Rio Tinto - Operational • Terramin – Angas Zinc Mine - Past

Operational • Newcrest (Lihir): injection of sea water to

cool a geothermal source - Prefeasibility • BHP-B (Olympic Dam) - Trial • Havilah Resources (Portia) - Trial • Water Proofing the East (City of

Walkerville) 893 ML/a - In development • Water Proofing Northern Adelaide (Cities

of Salisbury, Playford and TTG) 5 GL/a - Several Operational

• Water Proofing the West (City of Charles

Sturt) 2.3 GL/a. Several Operational • Water Proofing the South (City of

Onkaparinga) 2 GL/a - Several in commissioning stage

• Oaklands Park Stormwater Harvesting Scheme (City of Marion) 500 ML/a - Operational

• Adelaide Airport Stormwater Harvesting Scheme (SA Water) 400 ML/a - Operational

• Barker Inlet Stormwater Harvesting Scheme (SA Water) 400 ML/a - Operational

• Aldinga Treated Wastewater ASR Scheme (SA Water) 400 ML/a - Operational

• City of Unley Stormwater Harvesting and Reuse Schemes 95 ML/a - Operational


Please ensure you provide contact detail for further updates, water quality information and water bore survey.

Contact details:

Joe Ranford – Terramin Australia

ph: 8213 1415

[email protected]

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