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Freshwater Aquatic Organisms and Habitat (2004-2007) Rick Palmer Senior Fisheries Biologist Sharleen Hamm Aquatic Ecologist
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Outline 1.Purpose of Program – EA vs. Operational 2.Biological Setting 3.Impact Statements 4.Common Issues 1.Non-Fish Bearing Status 2.Water Withdrawal water supply winter road 3.Reference Lakes 4.Compensation
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Purpose of Program Collect sufficient information to: –characterize the existing environment –describe the baseline conditions –answer EA questions –assist the engineers in focussing the design of the mine plan to areas of minimal impact, and –inform development of the AEMP during the licensing stage Commit to developing a conceptual AEMP to support the EA process Develop AEMP based on the final approved mine plan and EA conclusions
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Biological Setting Project area drains to the north Numerous lakes drain into the Kennarctic R., which drains to Grays Bay Lakes contain lake trout and/or Arctic char Kennarctic R. contains lake trout, Arctic char (resident and anadromous) and forage species Approximately 50% of the lakes studied in the High Lake and Granite Lake drainage areas do not contain fish
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Biological Setting Barriers for fish between the Kennarctic R. and High Lake and Granite Lakes drainage areas No barriers for fish migration in the Kennarctic R. mainstem Streams are typically either wide with boulders or narrow with fines Kennarctic R. comprises a series of wide, deep pools linked together by shallow, fast moving reaches
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Biological Setting Lakes are: well oxygenated very soft low in nutrients little buffering capacity (highly sensitive to acidic input), and have detectable trace metal concentrations High Lake itself has elevated levels of metals (copper, cadmium and zinc) and is acutely toxic to fish
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2 VECs –Arctic char and lake trout 2 Impact Statements: –FF1: construction, operation, closure and post closure activities affecting surface water quality may have an effect on freshwater fish health and populations 3 pathways –FF2: construction, operation, closure and post closure activities affecting surface water quality may have an effect on freshwater fish habitat 4 pathways Impact Statements
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Impact Statements (cont) FF1: Health and Populations –Pathway 1: Discharge from Tailings Impoundment (L16) All parameters meet threshold values for the protection of aquatic life, except selenium and copper
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Impact Statements (cont) –Copper (CCME Guideline = 0.002 mg/L) Increases to 0.0033 mg/L immediately downstream of discharge point (June – Sept, Years 4, 5, 6, 10, 11) short term, temporary, low magnitude Background concentrations of up to 0.0058 mg/L No significant adverse effect
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Impact Statements (cont) –Selenium ( CCME Guideline = 0.001 mg/L) Increases to 0.0011 – 0.0019 mg/L immediately downstream of discharge point (June – Sept, Years 6, 10, 11) short term, temporary, low magnitude Other jurisdictions acknowledge unpredictable effects with wide range of guidelines. Body burden in fish more useful than water concentration No significant adverse effect Will monitor body burden in fish
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Impact Statements (cont) FF1: Health and Populations (cont) –Pathway 2 : Sedimentation from site runoff and road crossings Levels are predicted to remain below indicator thresholds No significant adverse affect
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Impact Statements (cont) FF1: Health and Populations (cont) –Pathway 3: Explosive Detonation Follow “Guidelines for the Use of Explosives in or Near Canadian Waters” (Wright and Hopky, 1998) No significant adverse affect
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Impact Statements (cont) FF2: Fish Habitat –Pathway 1: Sedimentation Mitigation, using best management practices and established thresholds (CCME) Monitoring during construction phase No significant adverse affect
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Impact Statements (cont) FF2: Fish Habitat (cont) –Pathway 2: Water Withdrawal from lakes L4 and L5 Summer: negligible impacts Winter: lake volumes (L4 and L5) will be reduced by 5-6%; water depth reduced by 0.3-0.6m Applied DFO protocol for winter water withdrawal No significant adverse affect
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Impact Statements (cont) FF2: Fish Habitat (cont) –Pathway 3: Channel Diversions Channels do not contain fish habitat or flow in/out of fish bearing lakes No significant adverse affect
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Impact Statements (cont) FF2: Fish Habitat (cont) –Pathway 4: Stream and Lake Infilling Impacts expected at four stream crossings and one lake crossing along the all-season road Draft No-Net-Loss Plan has been developed in consultation with DFO
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Common Concerns 1.Non Fish-Bearing Status High Lake: Not Fish-Bearing Extensive sampling (2004-2006) Fish capture methods and effort: gill nets: 20 sets; all depths; 1,170 hrs angling: 4 hrs trotline: 4 sets: 73 hrs minnow trapping 28 sets; 49 hrs Water quality program failed toxicity test at 2 locations concentration of copper, cadmium and zinc exceed CCME Guidelines by 50 to 100 times
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Common Issues (cont) 1.Non Fish-Bearing Status Other Lakes Fishing Effort: Extensive sampling was conducted (2004-2006) with a minimum of 2 methods/lake Gill nets, angling, minnow traps and/or electrofishing 14 lakes fished within mine footprint No fish captured
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Common Issues (cont) 2.Water Withdrawal – water supply Issue – DFO protocol is not appropriate for establishing thresholds for water supply Discussion why is the protocol acceptable in the NWT, but not Nunavut? what is an acceptable threshold? should we expand project footprint to accommodate a different supply lake (i.e., L718)? winter water supply vs. winter road construction - how do they differ?
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Water Supply Model
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Common Issues (cont) 2.Water Withdrawal - winter road Issue – Rating curve is not appropriate for determining lake volumes along the winter road Discussion approach was discussed in consultation with DFO road will only be operational for 2 years model indicates less than 2% loss of total lake volume
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Surface Area-Volume Relationship #1
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Surface Area-Volume Relationship #2
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Common Issues (cont) 3.Reference Lakes Issue - Reference lakes are within the mine footprint Discussion We have looked at 3 reference lakes, but they don’t fit the requirements Zinifex is committed to finding a suitable reference lake for the project
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Common Issues (cont) 4. Habitat Compensation Issue - Proposed habitat compensation may not be appropriate. Discussion Currently proposing artificial reef construction in L800 already impacted Considering fish habitat enhancement opportunities near Kugluktuk (discussions with HTO and DFO)
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