TERRAMIN AUSTRALIA Limited Angas Zinc Project

Water Topics –Water sources –Outcomes –Risk identification, management, control –Mine water demand –Modelling (groundwater) –Monitoring

MARP Outcome & Criteria OutcomeOutcome –No adverse impact to the supply of water to existing users and water dependent ecosystems CriteriaCriteria –Water to be measured for metals, flow, depth and organic content. All measurements are compared to baseline data.

Management Strategy ZERO DISCHARGE POLICY No contaminate water to leave site All engineering design and placement of infrastructure is set to achieve: ZERO DISCHARGE

Water Sources Sources of water –Rainfall –Permanent surface water –Ephemeral surface water –Ground water –Waste water

Water sources Mine is Eastern Mount Lofty Ranges, part of the prescribed surface water area and Murray River Catchment, adjacent to Angas-Bremer prescribed wells area Waters in the location of the mine –Burnside Creek (ephemeral) –Angas River –Aquifers: shallow and deep –Surface water runoff (storm events) –Flood plains (storm events) –Council Sewage Treatment Ponds

Catchments map

Water users Regional Users of Angas Catchment - surface & groundwater Users of Lake Alexandrina water Local Two current properties have shallow bores Mains water Waste water from Lagoons - Polo Club, Olive grove

Management Actions TSF - lined - Zero discharge Water storages - lined dams - Zero discharge Surface water management - clean/dirty separated - designed for ARI 1:100 Waste water lagoons - low permeability rocks & thick crown pillar Underground & surface process water contained within circuit. Underground - no flow out to environment – draw-down whilst pumping If large flows encountered we would pressure grout the walls

Mine water balance

In (m³/h)Out (m³/h) Fresh 8.4Tailings moisture 13.4 Mine water ingress 7.2Evaporation 0.2 Effluent 0.3 Water stores evaporation 0.3 Weighbridge 0.1 Concentrate moisture 1.3 Total in 15.6Total out 15.6

Mine water balance Mine will not discharge waterMine will not discharge water –The site is net water negative, with balance of requirements coming from potable supply source (SA Water) –Looking at Reverse Osmosis to reduce SA Water demand

Effluent Ponds Mine dewatering may intercept some infiltration of sewage ponds, adjacent to Tuckers SwampMine dewatering may intercept some infiltration of sewage ponds, adjacent to Tuckers Swamp Management: required for high E.Coli and faecal coliforms (measured) - health riskManagement: required for high E.Coli and faecal coliforms (measured) - health risk Current users of effluent – Polo club, Olive groveCurrent users of effluent – Polo club, Olive grove

Groundwater modelling AWE: Rick AldamAWE: Rick Aldam –Principal Environmental Scientist Groundwater draw down modellingGroundwater draw down modelling –To define any cone of depression of groundwater that is undergoing extraction

Groundwater modelling draw-down

2 Rain Water circuits 1 circuit for water that has contacted mining surfaces 1 circuit for uncontaminated surface water

Surface water monitoring

Ground water monitoring (plus TSF – 9 bores)

Ambient water typical levels Plot of metals in drill holesPlot of metals in drill holes

Ambient water typical levels Plot of TDS & pH in drill holesPlot of TDS & pH in drill holes

Management Target ZERO DISCHARGE POLICY No contaminate water to leave site All engineering design and placement of infrastructure is set to achieve: ZERO DISCHARGE