Australian Groundwater Technologies. making water work

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2 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

3 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.

4 Bores target the Brighton Limestone (marble), (contains the gold bearing qtz veins)

5 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.

6 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

7 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.

8 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) Depth to Groundwater (m) GROUNDWATER LEVEL /13 12/13 01/14 01/14 02/14 03/14 03/14 04/14 05/14 05/14

9 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

10 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

11 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.

12 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)

13 Bore yield (L/s) Private bore yields shown in blue 50 Investigation bore yields DWIB1, DWIB3, DWIB4, DWIB5 100 Bore Depth (m) Depth of old mine workings Fractured ground = high groundwater flows Yield decrease with depth DWIB3 250 DWIB1 DWIB4 DWIB Brighton Limestone Host rock of the Gold deposit. Low yield rock

14 Information collected during drilling (continued): Geophysical logging Acoustic televiewer Mapping of fractures (water bearing zones) Detection of thin beds Determination of bedding dip

15 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

16 Airlifting water during drilling of DWIB1 BH41 (all units) DWIB3 (Cox Sandstone) BH37 (all units) BHR01 (shallow water table)

17 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.

18 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. MINE WORKINGS GROUNDWATER DRAWDOWN INJECTION WELLS NB: Diagram illustrative and not Bird in Hand Gold Model.

19 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

20 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)

21 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

22 Please ensure you provide contact detail for further updates, water quality information and water bore survey. Contact details: Joe Ranford Terramin Australia ph: