TERRAMIN AUSTRALIA LimitedTERRAMIN AUSTRALIA Limited

Angas Zinc Angas Zinc ProjectProject

WaterWater

• Topics

– Water sources

– Outcomes

– Risk identification, management, control

– Mine water demand

– Modelling (groundwater)

– Monitoring

MARP Outcome & CriteriaMARP Outcome & Criteria

• OutcomeOutcome– No adverse impact to the supply of water No adverse impact to the supply of water

to existing users and water dependent to existing users and water dependent ecosystemsecosystems

• CriteriaCriteria– Water to be measured for metals, flow, Water to be measured for metals, flow,

depth and organic content. All depth and organic content. All measurements are compared to baseline measurements are compared to baseline data.data.

Management StrategyManagement Strategy

ZERO DISCHARGE POLICY

No contaminate water to leave site

All engineering design and placement of

infrastructure is set to achieve:

ZERO DISCHARGE

Water SourcesWater Sources

Sources of water

– Rainfall

– Permanent surface water

– Ephemeral surface water

– Ground water

– Waste water

Water sourcesWater 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 mapCatchments map

Water usersWater 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 ActionsManagement 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 Mine water water

balancebalance

Mine water balanceMine water balance

In (m³/h) Out (m³/h)

Fresh 8.4 Tailings moisture 13.4

Mine water ingress 7.2 Evaporation 0.2

Effluent 0.3

Water stores evaporation 0.3

Weighbridge 0.1

Concentrate moisture 1.3

Total in 15.6 Total out 15.6

Mine water balanceMine water balance

• Mine will not discharge water Mine will not discharge water – The site is net water negative, with balance The site is net water negative, with balance

of requirements coming from potable of requirements coming from potable supply source (SA Water)supply source (SA Water)

– Looking at Reverse Osmosis to reduce SA Looking at Reverse Osmosis to reduce SA Water demandWater demand

Effluent PondsEffluent Ponds

• Mine dewatering may intercept some Mine dewatering may intercept some infiltration of sewage ponds, adjacent infiltration of sewage ponds, adjacent to Tuckers Swampto Tuckers Swamp

• Management: required for high E.Coli Management: required for high E.Coli and faecal coliforms (measured) - and faecal coliforms (measured) - health risk health risk

• Current users of effluent – Polo club, Current users of effluent – Polo club, Olive groveOlive grove

Groundwater modellingGroundwater modelling

• AWE: Rick AldamAWE: Rick Aldam– Principal Environmental ScientistPrincipal Environmental Scientist

• Groundwater draw down modellingGroundwater draw down modelling– To define any cone of depression of To define any cone of depression of

groundwater that is undergoing extractiongroundwater that is undergoing extraction

Groundwater modellingGroundwater modellingdraw-downdraw-down

2 Rain Water 2 Rain Water

circuitscircuits

1 circuit for water that 1 circuit for water that has contacted mining has contacted mining surfacessurfaces

1 circuit for 1 circuit for uncontaminated uncontaminated surface surface waterwater

Surface Surface waterwatermonitoringmonitoring

Ground Ground waterwatermonitoringmonitoring

(plus TSF – 9 bores)(plus TSF – 9 bores)

Ambient water Ambient water typical levelstypical levels

Arsenic

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

AN 93 AN 43 AN 79 AN 40 AN 95 AN 47

Hole#

mg

/l

• Plot of metals in drill holesPlot of metals in drill holesZinc

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

AN 93 AN 43 AN 79 AN 40 AN 95 AN 47

Hole#

mg

/l

Lead

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

AN 93 AN 43 AN 79 AN 40 AN 95 AN 47

Hole#

mg

/l

Fluride

0

2

4

6

8

10

12

14

AN 93 AN 43 AN 79 AN 40 AN 95 AN 47

Hole#

mg

/l

Ambient water Ambient water typical levelstypical levels

TDS

0

5000

10000

15000

20000

25000

AN 93 AN 43 AN 79 AN 40 AN 95 AN 47

Hole#

mg

/l

• Plot of TDS & pH in drill holesPlot of TDS & pH in drill holes

pH

0

1

2

3

4

5

6

7

8

9

10

AN 93 AN 43 AN 79 AN 40 AN 95 AN 47

Hole#

pH

Management TargetManagement Target

ZERO DISCHARGE POLICY

No contaminate water to leave site

All engineering design and placement of

infrastructure is set to achieve:

ZERO DISCHARGE