Fisheries and Oceans Canada & Environment Canada’s Joint Intervention Presentation Ekati Mine BHP Billiton Diamonds Inc. Public Hearing Yellowknife, Northwest Territories DFO Review Team Fisheries and Oceans Canada EC Review Team Environment Canada February 2013
Overview • Environment Canada’s Roles and Responsibilities • DFO’s Roles and Responsibilities • Key Issues Related to: Freshwater Environment Atmospheric Environment Term of Water Licence • Closing Remarks Page 2
EC’s Roles and Responsibilities Environment Canada (EC): • Reviews proposals for environmental impacts falling within its mandate typically relate to: Water Quality and Quantity; Migratory Birds and Species at Risk; and Air Quality. • Provides expert advice and recommendations to the Wek’eezhii Land and Water Board. Page 3
DFO’s Roles and Responsibilities Fisheries and Oceans Canada (DFO): • Reviews proposals for environmental impacts falling within its mandate typically relate to: The management and protection of fish and marine mammals and their habitats. • Provides expert advice and recommendations to the Wek’eezhii Land and Water Board. Page 4
FRESHWATER ENVIRONMENT Page 5
Freshwater Environment Issue 4.1: Selenium Water Quality Benchmark Concern/Rationale: • BHP Billiton (BHPB) reviewed a water quality benchmark for selenium of 0.001 mg/L. • As identified by BHPB, DFO and EC believe that a fish tissue based benchmark/criteria is preferable to a water quality benchmark for selenium. Page 6
Freshwater Environment Recommendation 4.1: EC/DFO recommends that: • A fish tissue benchmark be set for selenium with an associated Management Response Plan. Photo Credit - P. Vecsei Page 7
Freshwater Environment Issue 4.2: Aluminum Water Quality Benchmark Concern/Rationale: • Golder Associates stated in the Aluminum Freshwater Toxicity Benchmark Report , “…it can be extremely toxic to fish under acidic (pH <6) or alkaline conditions (pH>8), but has relatively low toxicity to freshwater aquatic fauna between 6 and 8". • Even though pH has always remained constant between 6 and 8 in the receiving environment at the EKATI mine site, the Water Licence currently has the following condition regarding pH: “Any water or Waste from the Project that enters the Receiving Environment shall have a pH between 6.0 and 9.0, except surface runoff which shall have a pH between 5.0 and 9.0.” Page 8
Freshwater Environment Recommendation 4.2: EC/DFO recommends that the Board: • Replace: “Any water or waste from the project that enters the receiving environment shall have a pH between 6.0 and 9.0 , except surface runoff which shall have a pH between 5.0 and 9.0.” • With: “Any water or Waste from the project that enters the receiving environment shall have a pH between 6.0 and 8.0 , except surface runoff which shall have a pH between 5.0 and 9.0.” Page 9
Freshwater Environment Issue 4.3: Nitrate Site Specific Water Quality Objective Concern/Rationale: • BHPB has proposed a Site Specific Water Quality Objective for nitrate as a function of water hardness and individual toxicity test results. • However, results from the 2012 fish monitoring program have not been analyzed yet to determine what the potential impacts are to fish species from the changes identified in the plankton community. This information is important to have prior to the Board approving a Site Specific Water Quality Objective for nitrate. Page 10
Freshwater Environment Recommendation 4.3: EC/DFO recommends that: • In support of the Independent Environmental Monitoring Agency's recommendation, an interim Effluent Quality Criteria of 10.0mg/L be set for nitrate for a two year period to allow the data from the 2012 fish monitoring program to be analyzed and incorporated into the Site Specific Water Quality Objective assessment. Page 11
Freshwater Environment Issue 4.4: Management Response Framework Concern/Rationale: • BHPB is proposing a management response framework based on only two action levels, 75% of benchmark as a low action level with a high action level being reached when levels are at 100% of the benchmark. BHPB believes that a one year time frame provides an adequate amount of time to respond and mitigate potential effects before the aquatic environment is impacted. • DFO and EC are concerned that the proposed action levels do not provide enough of an early warning of environmental effects and that a one year response time frame may not be appropriate. Page 12
Freshwater Environment Recommendation 4.4: EC/DFO recommends that: a) To be consistent with the draft WLWB guidelines, a third action level be added to the proposed framework to be more protective of the aquatic receiving environment. A low action level could be added which would be reached when 50% of the benchmark is met; b) Appropriate time frames for each action level should be determined for parameters on a case by case basis to ensure effects are mitigated before impacting the aquatic environment; c) In addition to the Aquatic Effects Monitoring Program (AEMP) data, Surveillance Network Program (SNP) Monitoring data be used to inform the Management Response Framework where applicable; and d) The Management Response Framework be included in the renewed Water Licence within the AEMP Section. Page 13
Freshwater Environment Issue 4.5: Drawdown of Water Source Lakes Concern/Rationale: • BHPB has suggested the following wording for the Water Licence as a merging of the current clauses D.6 and D.7: “The Drawdown of Little, Falcon, Grizzly, and Thinner Lakes shall not exceed one (1) metre from the pre-operational water level, or as otherwise approved by Fisheries and Oceans Canada.” • The one metre maximum drawdown is in place to avoid impacts to littoral habitat. • However, there is confusion as to what the 1 metre drawdown is currently being compared against. Page 14
Freshwater Environment Recommendation 4.5: DFO recommends that: • The wording proposed by BHPB be accepted with the provision that the pre-operational water level is identified and clearly marked on the staff gauge to easily determine if the 1m maximum drawdown is being adhered to. Page 15
Freshwater Environment Issue 4.6: Intake Screens to Prevent Impingement/ Entrainment of Fish Concern/Rationale: • Proper intake screens are designed to avoid the loss of fish due to impingement and/ or entrainment. • BHPB has proposed to amend the wording of Clause 4.5 in Part D (Conditions Applying to Water Use) of the WL to the following: “The freshwater intake pumps shall operate in accordance with the Fisheries and Oceans Canada Freshwater Intake End-of- Pipe Fish Screen Guideline, 1995, or subsequent editions, or as otherwise approved by Fisheries and Oceans Canada.” Page 16
Freshwater Environment Recommendation 4.6: DFO recommends that: • The WLWB accepts BHPB’s proposed change to the wording of Clause 4.5 in Part D of the Water Licence. • If preferred, alternative wording could be: “The Permittee shall construct and maintain the water intake(s) with a fish screen designed to prevent impingement and/ or entrainment of fish, with a maximum design opening of 2.54mm (0.10 inches), and shall be in accordance with the detailed guidance referred to in Schedule X ”. Page 17
Freshwater Environment Issue 4.7: Winter Water Withdrawal Concern/Rationale: • Excessive amounts of water withdrawn from ice-covered waterbodies can impact fish through oxygen depletion, loss of over-wintering habitat and/or reductions in littoral habitat. • Based on discussions between DFO and BHPB, the Proponent has agreed to follow the DFO Protocol for Winter Water- Withdrawal from Ice-covered Waterbodies in the NWT and NU for Grizzly Lake and Falcon Lake. Page 18
Freshwater Environment Recommendation 4.7: As proposed by BHPB, DFO recommends to the Board that: • A condition be added to reflect that the DFO Protocol for Winter Water Withdrawal from Ice-covered Waterbodies in the NWT and NU be followed for water source lakes at the Ekati Diamond Mine. Two suggested versions are provided below for the Board’s consideration: 1) Under-ice Drawdown of Little, Falcon, Grizzly, and Thinner Lakes shall follow procedures outlined in the DFO Protocol for Winter Water Withdrawal from Ice-covered Waterbodies in the NWT and NU, or subsequent editions, or as otherwise approved by DFO; and 2) In one ice-covered season, total water withdrawal from a single waterbody is not to exceed 10% of the available water volume calculated using the appropriate maximum expected ice thickness in accordance with the detailed guidance outlined in Schedule X. Page 19
Freshwater Environment Issue 4.8: Cujo Lake Proposed Mixing Zone Concern/Rationale: • The method used by BHPB to set some of the Effluent Quality Criteria for the King-Cujo-Lac du Sauvage Watershed relies on using Cujo Lake to provide sufficient mixing to meet proposed benchmarks for nitrate-N, ammonia-N and copper. Page 20
Freshwater Environment Recommendation 4.8: EC/DFO recommends that: • The Effluent Quality Criteria for Station 1616-43 should be set to minimize the mixing zone in Cujo Lake, in order to reduce the area of the lake which may have chronic toxicity effects. Page 21
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