Snap Lake Working Group Meeting 3 09.29.2014 The De Beers Group of Companies
Early Life Stage (ELS) Testing The De Beers Group of Companies
Contents Page 1. ELS fish toxicity Testing 2. Results of August 4 Fathead Minnow ELS test 3. Investigation 4. Preliminary Results of investigation 5. Ongoing work and reporting The De Beers Group of Companies 2
Early Life fe St Stage ge (ELS) fis fish toxicity ty testi ting ng Required by the water licence as of July 17, 2014 • A 7-d test with Rainbow Trout to assess embryo viability, and a 7-d test with larval Fathead • Minnow to assess survival and growth • First time a Fathead Minnow larval ELS test performed for Snap Lake – August 4, 2014 sample • Sample is a composite sample from 4 diffuser locations, to be tested at 100% concentration only The De Beers Group of Companies 3
Results ts of Au August ust 4 Fathe head ad Minnow w ELS test t • Test initiated August 7, preliminary results received on August 11-12, final results received August 25 By Day 4, fish in the lake water were not surviving; by Day 7, most fish in the test were • dead • Control fish had 100% survival • Initiated an investigation into the results of the toxicity results – two part investigation: confirmatory sampling and data review – using the USEPA toxicity and Canadian MMER guidelines as guidance • Notified the Inspector and the Board The De Beers Group of Companies 4
Inve vesti stigat gation on Confirmatory Sampling 1) Leftover unused water from the August 4 toxicity sample shipped to laboratory for chemistry analysis – August 14 2) Effluent (SNP 02-17B) collected for acute Rainbow Trout and Daphnia magna toxicity tests and supporting water chemistry to confirm the effluent is not acutely lethal – August 21 3) Laboratory liaison to order test organisms for ELS tests – August 15 to 21 4) Diffuser area sampled for additional 7-d Rainbow Trout, 7-d Fathead Minnow, and 3-brood Ceriodaphnia toxicity tests and supporting water chemistry – August 26 5) Effluent (SNP 02-17B) collected for supporting water chemistry – August 26 The De Beers Group of Companies 5
Inve vesti tigat gation ion Review of Data Review the following data: • – August 4 toxicity sample – August 4 water chemistry sample data – August SNP water chemistry data (effluent and diffuser stations) – August 21 toxicity and water chemistry samples – August 26 toxicity and water chemistry samples – Comparison of summer 2014 water chemistry – any spatial and temporal trends? – Site operational records – any operational conditions of note? – Review of field and laboratory handling procedures and QA/QC protocols The De Beers Group of Companies 6
Preliminar minary y Results ts of In Inve vesti stigation gation Confirmatory Sampling – August 26, 2014 • Acute Rainbow Trout and Daphnia magna tests – preliminary results indicate effluent was not acutely toxic • Fathead Minnow 7-day ELS test results indicated test water was not toxic (maximum 5% mortality in test fish and 0% in control fish) • Rainbow Trout ELS test – preliminary results indicate no statistical difference between test fish and control indicating that effluent was not toxic • Ceriodaphnia result – decreased reproduction in 100% effluent sample (IC25 = 82%) The De Beers Group of Companies 7
Preliminar minary y Results ts of In Inve vesti stigation gation Confirmatory Sampling 1) Leftover unused water from the August 4 toxicity sample shipped to laboratory for chemistry analysis – August 14 2) Effluent (SNP 02-17B) collected for acute Rainbow Trout and Daphnia magna toxicity tests and supporting water chemistry to confirm the effluent is not acutely lethal – August 21 3) Laboratory liaison to order test organisms for ELS tests – August 15 to 21 4) Diffuser area sampled for 7-d Rainbow Trout, 7-d Fathead Minnow, and 3-brood Ceriodaphnia toxicity tests and supporting water chemistry – August 26 5) Effluent (SNP 02-17B) collected for supporting water chemistry – August 26 The De Beers Group of Companies 8
Review w of D Data • August 4 failed sample was slightly turbid with elevated levels of metals (aluminum, iron, zinc) compared to Snap Lake baseline but not at concentrations of environmental concern • TDS, nitrate, other metals similar to historical concentrations • On the basis of the preliminary review, no obvious rationale for the observed toxicity in the August 4 sample • All other testing appears to be not toxic, all other chemistry samples typical of past discharges (final results still pending) The De Beers Group of Companies 9
Next St Steps ps • Mid October De Beers will have final results • Submit to the Board as discussed Oct 21 The De Beers Group of Companies 10
Questi estions ns? The De Beers Group of Companies 11
Water Treatment Studies - Status The De Beers Group of Companies
Water Treatment Studies - Status • De Beers conducted limited off-site testing in June – August 2014, to further evaluate technological options for reducing TDS loading to Snap Lake. • Consistent with pre-feasibility studies of technologies presented in TDS Response Plan • Results confirm that reverse-osmosis based technology can be up to 95% effective in removing TDS from Snap Lake Mine Effluent. The De Beers Group of Companies 13
Water Treatment Studies - Status • Ongoing evaluation will confirm: secondary treatment (e.g., evaporation and/or crystallization) o Percentage bleed and configuration o Final waste types and volumes o • Final evaluation of the technology that is most effective, and also most appropriate for Snap Lake, will be presented in a report that presents results of the evaluation of technological, environmental and economic tradeoffs This BATEA-type study will be submitted as part of the water licence amendment process • Waste Generation Other Considerations Energy Consumption Reliability = ↑ ↑ TDS removal GHG Emissions Scalability Operating Cost Effectiveness Infrastructure Temporary Brine Storage Seasonality of Road The De Beers Group of Companies 14
Treatment Implementation Timeline The De Beers Group of Companies 15
North Pile Activities The De Beers Group of Companies
Contents Page 1. North Pile Operations and West Cell Phase I Development 2. Phase II Design and LoM 3. Potential considerations for closure The De Beers Group of Companies 17
North Pile Operations and West Cell Phase I Development Current operations focused in the East Cell • Pending on permitting approval, initial construction of West Cell • (Phase I) to start in early 2015 • Access roads and ditches potentially to be started in 2014 • Deposition of fine PK within the West Cell expected for January 2016 The De Beers Group of Companies 18
North Pile Operations and West Cell Phase I Development IL 7 lake Stockpile organics West Cell (Phase I) Starter Cell IL 6 ditch WMP EastCell Dorms Sump SP 5 Grout Curtain Processing Plant The De Beers Group of Companies 19
Phase II Design Considering Life-of-Mine (LoM) Preliminary design package for Phase II (expansion of North Pile), • including life-of-mine plan is tentatively scheduled for 2016 • Design focus remains in maintaining a stable and environmentally sustainable facility while allowing for a continuous mine operation • Preliminary consultation indicates that a height raise may be preferred over a footprint expansion • Closure considerations for the North Pile will be included The De Beers Group of Companies 20
Phase II Design and LoM – Design concepts to be evaluated starting Q4 2014 Studies to be initiated in the remainder of 2014 to evaluate the following: • Potential optimization of West Cell (Phase I) construction sequence, considering current North Pile footprint and LoM volumes • Potential opportunities in current North Pile design, including feasibility of stacking coarse PK and allowing for increase fine PK storage in the West Cell without significantly increasing current facility footprint • Potential opportunities for optimization of mid-term deposition methodology to improve long term construction methods and slurry/surface water management within the facility. The De Beers Group of Companies 21
Phase II Design considering LoM - Maintaining a stable and environmentally integrated facility East Cell Starter Cell at ~480 masl (~ 40 m above Snap Lake) Approximate West Cell Phase I footprint The De Beers Group of Companies 22
Potential considerations for closure Section Title Results of the studies to be initiated in the remainder of 2014 and that will continue through 2015 will also provide valuable information in terms of: • North Pile capping requirements and potential capping layer mid to long term behavior • North Pile long term surface water management options The De Beers Group of Companies 23
Questi estions ns? The De Beers Group of Companies 24
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