YESAA Designated Office Evaluation...

of 85

YESAA Designated Office Evaluation Report 1) Environmental and Socio-economic Assessment File Information Project Title Installation of an Adit Plug and Associated Workings at the Tom Valley Property

Project File Number 2008-0242

Proponent Name Hudson Bay Mining and Smelting Co., Limited

Evaluation Start Date October 24, 2008

Contact Person Stephen West

Evaluation Finish Date December 19, 2008

Designated Office Recommendation Summary Pursuant to Section 56(1) of the Yukon Environmental and Socio-economic Assessment Act it is recommended to the decision body(ies) that the project be allowed to proceed, subject to specified terms and conditions, as the Designated Office has determined that the project will have significant adverse environmental or socio-economic effects in or outside Yukon that can be mitigated by those terms and conditions. 2) Designated Office Assessment Officer Identification Designated Office Watson Lake

Assessment Officer Steven Jakesta

3) Decision Body or Bodies and Potential Authorization Identification Decision Body Potential Authorization(s)

Required Act or Regulation

YG Department of Energy, Mines and Resources – Minerals Resource Branch YG Department of Energy, Mines and Resources – Land Use Yukon Workers’ Compensation Health and Safety Board

Water Licence amendment Quarry Permit Magazine Licence

Waters Act Lands Act Occupational Health and Safety Act

4) Project Activity or Activities Included in Schedule 1 of the Regulations* and not

Excepted Proposed Activity Part Item Deposit of waste into water 9 12 * Assessable Activities, Exceptions, and Executive Committee Projects Regulations

of 85

5) Project Location Latitude and Longitude or UTM Coordinates NW Boundary 441438E 7004648N Zone 9

NE Boundary 441987E 7004656N Zone 9

SW Boundary 441990E 7003796N Zone 9

SE Boundary 441433E 7003796N Zone 9

NTS Map Sheet # 105O/01

Nearest Community Ross River

Distance 175 km

First Nation Traditional Territories Involved Kaska: Liard First Nation, Ross River Dena Council Watershed(s) and Drainage Region Major Drainage Area: Pacific Sub Drainage: Pelly Sub-Sub Drainage: Macmillan Nearby Watercourse(s) or Waterbody(s) Sekie Creek #2, Upper South Macmillan River 6) Statement of Project Scope Project Scope: The principal activity of this project is the installation of an adit plug and related activities to manage the discharge of wastewater from the adit into Sekie Creek and the South Macmillan River. The project occurs on the Tom Valley property, located at the northern extent of the North Canol highway, and will occur over an estimated 12 week period during summer. Principal activities include: • Installation of an adit plug and pressure relief drift to facilitate flooding of the underground workings; • Installation of a partial waste rock cover; • Construction of a lined discharge channel and temporary sludge containment pond; • On-going monitoring. Accessory activities include: • Temporary camp and associated activities (maximum capacity of 10 people); • Rehabilitation of existing on-site road and re-contouring of waste rock dump surface; • Use of water from South Macmillan River (approx. 300m3/day) for non-potable water and adit plug construction; • Use of aggregate from a YG gravel pit (approx. 250m3) for adit plug construction; • Use of fuel (approx. 4000 L stored in drums at Macmillan pass airstrip) and explosives (approx. 680kg). Note on the Temporal Scope of Project The project scope indicates that these activities will occur within a 12 week period during summer. This is intentionally vague in order to provide some flexibility to the proponent

of 85

as to when exactly that work may occur. For example, once this assessment is finished there remains a timeline for the decision-making and regulatory processes. Combined with the limited available season, technical limitations and financial factors it becomes difficult to say with certainty when the project will be implemented. It is important to note however that there is a more definite timeline set for this work to occur within. As noted in this report, the current water licence (QZ08-080) expires on December 31, 2012. There is logical and perhaps legal impetus to complete the work prior to this date, appreciating that it is the proponent’s intention to complete it next summer. Assuming that work did occur in summer, 2009, this timeline would allow the adit plug to be installed followed by three full years of monitoring, and hopefully stabilization of the site to predicted and required standards. I believe this is an appropriate duration, or temporal project scope, for this assessment to consider. As such the temporal scope for this project will be a three year period. Beyond this point it becomes difficult to determine with certainty what the potential significant adverse effects may be. I believe it is reasonable for this project to require further assessment at that point in time.

7) Project Notification List Proponent – Hudson Bay Mining and Smelting Co., Limited – Stephen West Decision Body – YG: EMR – Minerals Resource Branch YFN Government – Kaska: Liard First Nation – Laurie Allen YFN Government – Kaska: Ross River Dena Council – Testloa Smith, Nora Ladue Interested Person – Yukon Fish and Wildlife Management Board – Graham Van Tighem Interested Person – Yukon Salmon Sub Committee Adam Greetham Allan Doherty Andre Fortin Andrea Fischer Andrea Morgan Andrea Wilson Angus Cumming Annick LeHénaff Ben Campbell Benoit Godin Brian Charles Brian Crist Brian Hemsley Brian Miller Brian Smart Briar Young Bruce Funk Cameron Beemer Charles MacQueen Cheryl Kawaja

Hilary Gladish Irving Leblanc Jacine Fox James Miller James Smith Jason Herbert Jean-Francois Latour Jean Legare Jean Lucas Jeff Bailey Jeff Hamm Jeff Peters Jeffery Green Jennifer Russell Jim Connor Joe Murdock Joe Yanisiw Joel Wilkinson John Ryder John Witham

Michael Wark Mike Burke Mike Kroeker Milada Pardovicova N. Hughes Nancy Moore Nathalie Lowry Nathan Ferguson Nichole Hulstein Nichole Speiss Noreen Hirtle Ossie Venasse Patricia Randell Pat Tobler Patrick MacDonell Paul Kloepfer Peter Jakesta Phil Smerchanski Randy Carey Rob Smith

of 85

Cheryl Thompson Christoph Altherr Chuck Tobin Column McCready Corey De La Mare Corrine Porter Dan Davidson Darren Kippenstein Darryl Froese Dave Croft Dave Joe Dave Wotton David Bridger David Isopo Derek Loots Development Assessment Branch Diane Sheldon Diarmuid Collins Don MacDonald Donn Wilkinson Doug Davidge Douglas R. Brown Drew Mildon Emma Cunningham Eric Hellsten Ernie Hallonquist Evalina Zamana Francis Wilson Paglicawan Gail M. LaRocque Gary Bauer Grant Lundy Greg Kent Gregory Keating H. Leo King Habitat Biologist Heather Desmarais

Judy Shannon Justina Michel Justine Davidson Kai Woloshyn Karen Clyde Kate Bartel Katherine Cumming Ken Reeder Kevin Maichen Kevin Rumsey Kim Cholette Kim Kalen Kim Redies Kirk Cameron Kurt Gantner Kurt Neunherz L. Crawford Lara Lewis Laura Hoversland Leonard Linklater Les Laverdure Leslie Peters Lewis Rifkind Lin Ward Mac Hislop Mark Brodhagen Mark Evans Mark Nelson Mark Stephens Mark Vainio Martin Eckervogt Martin Haefele Mary Walden Matthew Nefstead Meghann-Leigh Willard Melanie Brais Michael Setterington

Ron McFadyen Roxanne Schofield-Wray Roy Slade Roy Wares Ruth Wilkinson Ryan Drummond Sam Ahad Sam Cheng Sandra Horvath Scott Cole Scott McAllister Sean Collins Sean Smith Sebastian Schnuelle Stephen Hureau Stephen Walsh Steve Gordey Steven Bartsch Susan Gleason Tara Christie Ted Murphy-Kelly Terry Eisenman Tim Moon Tom Cove Tor Forsberg Trevor Luft Vanessa Law Wade Strogan Warren LaFave Wayne Kettley William Polonsky YG Community Services Yukon Energy Corporation Yukon River Inter-Tribal Watershed Council Yvette Brown

*See Appendix I - Summary of Responses from Interested Persons and Others

of 85

8) Background Information

1. ASSESSMENT CONTEXT The assessment of environmental and socio-economic effects, including cumulative effects, is in accordance with Section 42 of YESAA. The mitigations identified herein are proposed to address project effects that the assessor believes to be potentially significant and adverse. They do not preclude the application of other mitigations as required by relevant legislation. The determination of significance for project effects relies upon qualification, and where possible, quantification of the following factors: magnitude; duration; frequency; reversibility; geographic extent; socio-economic context; and the likelihood of effects. This assessment will speak to these factors where applicable. 2. MATTERS CONSIDERED IN THIS ASSESSMENT 2.1 Site History The Tom Valley adit and associated workings were initiated in 1971 and formally closed in 1993. The exploration started with two portals, termed north and south, that meet approximately 40m from the outer face. The underground workings include one decline that is currently submerged, and two inclines that have groundwater drainage. These three branches begin approximately 500m in from the portal opening. The west and east zone inclines are each approximately 1km in length while the decline appears to be slightly longer at 1.5km. In total the workings are 4km in length and underground exploration resulted in the removal of 145,100 tons of rock. The majority of this is stored below, and to either side of the north portal, in the waste rock dump. The formal closure in 1993 satisfied reclamation requirements established by the Department of Indian and Northern Affairs. The south portal did not have any drainage and was simply backfilled. The north portal did have drainage and was backfilled in addition to the placement of pipes to facilitate continued drainage. In 1999 an inspection revealed that the north portal bulkhead was destroyed, likely from a blockage in the drainage pipes or an ice plug. In 2000, the area around the adit was cleared and a steel grill was installed 10m within the portal opening. The grill prevented access while continuing to allow the year-round adit drainage into Sekie Creek #2. The Tom Valley property is currently held under a series of leases by the Hudson Bay Mining and Smelting Co., Limited (“HBMS”). HBMS has a Type B water licence (QZ08-080) regulating the adit discharge. This licence expires on December 31, 2012. There are a number of important conditions in this licence that provide additional context for this assessment. First, the licence prescribes an effluent quality standard (“EQS”) that is to be met by March 12, 2009. The EQS is as follows:

of 85

Part D – Effluent Quality Standards 17. After March 12, 2009, a grab sample of any Waste discharged at Station W5, and any

other point of entry of a Waste discharge into receiving waters, shall meet the following effluent quality standards:

Parameter Concentration

Arsenic (dissolved) 1.0 mg/L Copper (total) 0.6 mg/L Lead (total) 0.4 mg/L Nickel (total) 1.0 mg/L Zinc (total) 1.0 mg/L

It is important to note that the prescribed EQS was a condition of the original licence granted in 1999 (QZ99-046). The timing for when this condition was to come into effect has been deferred three times through water licence amendments. The rationale for these amendments, and the subsequent delay in achieving this standard, was for the proponent to gather more information. Second, the licence prescribes minimum monitoring requirements through Part E – Monitoring, conditions 18 – 21. It is constructive for this assessment to understand what monitoring is currently required. This will ensure that our recommendation provides added value instead of overlap. Monitoring requirements include:

• sample locations (i.e. stations W2, W3, W3B, W5, W6, W8, W11, W12, W13); • data parameters;

− field measurements; conductivity, pH, water temperature, rate of flow, field notes,

photographs; − laboratory analysis;

physical tests – pH conductivity, water temperature, Total Suspended Solids, hardness;

dissolved anions: alkalinity, total sulphate; total and dissolved ICP metals including but not limited to – aluminum,

antimony, arsenic, barium, cadmium, calcium, chromium, copper, iron, lead, nickel, selenium, silver, thallium and zinc;

• frequency of monitoring efforts (i.e. at each station in May and September of each year); and

• a reference for standard methods of data collection. Third, the licence required the Licensee to submit a detailed plan for remediation activities of the mine

of 85

adit and drainage by November 18, 2008. This is detailed in Part F – Plan, conditions 22 – 23. This plan was to include at a minimum:

• preliminary design drawings of the adit plug and associated structures; • proposal for the effluent standards of any discharge from the site to any receiving waters,

upon completion of the remediation activities. 2.2 Project Purpose The proposal states that “the purpose of plugging the adit is to flood underground workings, submerging exposed reactive walls, which will lead to a decrease in the rate of oxidation and subsequent acid generation and metal leaching”. It also states that “the purpose of plugging the adit and seeking new effluent quality standards is to achieve the following objectives:

• Improve long-term water quality of the adit discharge at the Tom Property; and

• Obtain achievable discharge objectives/criteria, which consider natural background conditions of the Tom Property and Macmillan Pass area.”

This proposal presents a very unique situation for assessment. This site was an existing quartz exploration project that was formally closed. Since the 1970’s the adit has been discharging waste water with metal concentrations that have steadily increased and pH that has steadily decreased. While these attributes may have stabilized over the last nine years of sampling, their extent continues to be concerning to regulators. This concern has been formalized through the water licence conditions noted above. Aside from the EQS required through this licence, I am not aware of any other regulatory vision for what the longterm goals and objectives are for this site. I can only assume that the EQS put forward by the Water Board is the current regulatory vision. This places it in distinct contrast to the proponent’s vision of eventually mirroring the elevated background levels. The compelling issue for this assessment is to what extent does it need to consider the remediation goals for this site, a large part of which is the EQS? Does this assessment have a role in determining if the proposed activities will achieve the EQS? The answer to these questions is that I am required to make a recommendation or referral based on an evaluation of this project and its activities. Central to this outcome is that I understand and can determine if project activities will have significant adverse effects. Further, where such effects are identified I am responsible for recommending appropriate mitigation so that they are no longer significant. This project seeks to improve an existing site that is currently contributing to detrimental water quality in the region. Essentially the project is composed of a series of mitigation measures intended to alleviate existing adverse effects. In considering the stated purposes it would seem that the project will have an overall positive effect. However the proponent acknowledges that achieving this long term positive change may require a short term worsening of the situation. Namely, the predicted spike in metal concentrations during the initial flushing period and any uncertainties about the short and long term forecast. From my perspective this is the barometer for significance and adversity. If it is

of 85

determined that as a result of project activities conditions become worse, there is a potential for significant adverse effects. Conversely, if it is determined that as a result of project activities conditions improve, this will generally be viewed as a positive effect. The extent of whether effects are significant and positive or adverse will depend on a number of factors that will be examined within this report. The complexity posed by this project is that it will most likely be a mix of both outcomes. The project may result in short term significant adverse effects (i.e. worse water quality) in the effort of alleviating existing adverse effects for the long term. In closing this section, it is important to reiterate that this is not an assessment of an over-arching remediation plan for the site. There is a mechanism for assessing such plans under the YESA Act, however this proposal was not intended nor does it fit with that process. Instead this is a proposal with distinct project activities that are assessable on their own merit. It has been very compelling in assessing these activities to question what the greater goals should be for the site and determine if these activities are achieving those goals. However, I don’t believe I have the mandate to consider these matters. Determining remediation goals for the site and how best to achieve them is the mandate of the regulatory process, and specifically the Decision Body in coordination with the Water Board. 2.3 Scope of Assessment Temporal Scope As noted in the project scope, the temporal scope of this project is approximately three years in order to match the timeline for the current water licence. However the temporal scope of this assessment will consider the duration of activities plus the duration of their effects to the extent possible. Spatial Scope The spatial scope of this assessment will vary and consist of the footprint of project activities in combination with the relevant footprint of valued components considered. Detailed List of Project Activities The following list is intended to provide structure for the evaluation report. It outlines the main project components and their corresponding activities with relevant details. All activities listed confer with the final project scope included in this report. The use of heavy machinery, human presence and monitoring activities are implied where relevant. Main project components will be referenced when qualifying the temporal and spatial overlap between the project and values.

Project Activity List 1. Use of temporary camp

• Use of truck mounted campers or trailers; maximum of 10 people and up to 250 person days.

• Non-potable water to be stored in holding tank and sourced from the South Macmillan or one of its tributaries.

• Drinking water to be bottled and delivered. • Use of a porta-potty.

of 85

• Greywater managed via a greywater pit. • All garbage, debris and other wastes to be removed from site and disposed in

proper facilities.

2. Transport, handling and storage of petroleum products • Approximately 4000 L stored in drums at Macmillan pass airstrip.

3. Rehabilitation of existing road

• Gravel extraction from nearby YG pit and placement as needed.

4. Underground work • Transport, handling, storage and use of explosives (approximately 680kg). • Preparing adit.

− Refurbishing adit from the portal to proposed plug location. − Placement of existing piping and ventilation equipment behind proposed

plug location. − Securing work area through scaling, rock bolts and mesh as required.

• Installation of pressure relief drift − Use of drill and blast techniques. Relief drift placed 50-100m inside

existing drift with a height of 20m. Estimated removal of 300 tonnes of rock, placed on waste rock pile.

• Installation of adit plug. − Placement of overflow berm (1.0m high barrier behind proposed plug

location) to control sludge. − Placement of piping to act as a conduit for adit discharge during plug

construction. − Plug area, 90m in from portal, to be scaled, slashed and tapered.

Drilling sixty 5m long holes that will be grouted around the plug perimeter. Plug to be 10m long using 300m3 of concrete.

− Use of water from South Macmillan River (approximately 300m3/day). − Use of aggregate from YG gravel pit (approximately 250m3). − Installation of portal grate.

• Flooding of adit workings. Estimated area of 26,600m3 and flooding period of 30 days based on a median flow rate of 10 L/s.

5. Aboveground work

• Construction of temporary sludge containment pond. − Built on top of waste rock pile. Estimated to be 30m x 35m with side

berms of 1.5m in height. Built using waste rock, lined with an overflow channel.

− Encapsulation to occur once sludge has freeze dried over a minimum of two seasons.

• Waste rock pile − Re-contouring of waste rock pile to promote surface run-off to lined

discharge channel. − Installation of partial waste rock cover using 60 mil High Density

of 85

PolyEthylene followed by 50cm barrier layer using local talus. Expected surface coverage of 75% or 15,000m2.

• Construction of lined discharge channel. − Channel excavated from adit discharge to Sekie Creek #2. Involves

placement of a 0.3m sand layer, 60 mil HDPE liner and barrier layer. Potential use of rock gabions to stabilize channel.

2.4 Project Alternatives The proponent provided extensive information related to potential alternatives for achieving their purposes. In addition to the adit plug and lined discharge channel, which form this proposal, they considered the following options:

• High Density Sludge Treatment • Open Limestone Channels • Caustic Dosing Tank

The alternatives assessment reviewed and assigned a ranking for the effectiveness, implementation, environmental impact and socio-economic impact for each of these options. The adit plug was given the highest ranking. The lined channel and caustic dosing tank were second with equal ranking followed by the final two options. The utility of these alternatives in this assessment is to provide further context on the proposed activities. The proponent has not included these alternatives as viable activities to be assessed in parallel to what’s proposed. As such they have not been included in the project scope. 2.5 Valued Environmental and Socio-economic Components Based on the full and fair consideration of views and information, the following valued components have been considered in the evaluation of this project:

1 Environmental Quality 2. Water Resources 3. Aquatic Resources 4. Wildlife and Wildlife Habitat 5. Health and Safety 6. Effects of the Environment on the Project

of 85

3. ENVIRONMENTAL AND SOCIO-ECONOMIC SETTING 3.1 Location The project is located in a very remote area situated 175km northeast of Ross River, the nearest community. The site is accessible by road and air during summer months. Access by road starts in Ross River via ferry across the Pelly River and then along the North Canol highway. The main project components, namely the adit and waste rock pile, are roughly 3km southeast from the highway along an access road that starts at the Macmillan Pass airfield. Access by air uses this existing airstrip, an area where the temporary camp is to be placed. In winter and shoulder seasons the North Canol highway and airstrip are usually not maintained and essentially the project area is inaccessable during this part of the year. 3.2 Physical Environment Topography and Geomorphology The project is located within the Selwyn Mountains ecoregion (#171) which is part of the Taiga Cordillera Ecozone. This region is characterized by high-elevation mountain ranges and the adit certainly finds itself within these ranges (Smith, Meikle and Roots, 2004). It is located at 1440 meters above sea level (“mASL”) with a 2087 mASL peak to the northeast and an 1816 mASL peak to the southwest. This places the adit on a continuous slope of approximately 23° (43% slope). As per the proposal, the upper hill slopes “are underlain discontinuously by colluvium with bedrock” and “the lower slopes are underlain by debris flow fans at the gully outlets and fluvial deposits in the valley bottoms”. The valley at this location appears to be approximately 150m wide from the adit and equally steep on both sides. As per the proposal “geohazards in this area include rockfall, debris flows, and snow avalanches”. Avalanched debris incidents occurred in May 2005 and May 2006, the latter completely covering the adit. The Selwyn Mountains ecoregion is known to be within “the widespread discontinuous permafrost zone”. However, observations indicate elevations above 1300 mASL to the north and 1450 mASL to the south experience continuous permafrost (Smith, Meikle and Roots, 2004). In terms of earthquake history, there have been 19 earthquake epicenters recorded within 50km of the adit. These earthquakes occurred between 1963 and as recently as 2002 with 7 occurring within the last 10 years. Magnitudes ranged from 2.2 – 4.1 (Geological Survey of Canada, 2004). Geology The Tom property is predominately a zinc-lead deposit and “contains two physically separate galena-sphalerite-barite lenses in black shale of the lower Earn Group” (Soroka and Jack, 1983). According to Kwong and Whitley (1992), “rocks giving rise to acid rock drainage belong to the Lower Earn Group… comprising black, carbonaceous and siliceous shale of marine origin, chert pebble conglomerate and some siltstone”. Specifically, the Sekie Creek #2 watershed is underlain by four rock groups with the majority of it

of 85

associated with Tom Sequence shales. As per the proposal, “these rocks are talus forming, silver blue weathering, platy siliceous shale, minor chert. Pyrite is abundant throughout the rocks in this sequence and can consist of up to 3% to 8% pyrite”. Macintosh Creek is entirely underlain by the Tom sequence and the watershed itself has had limited human impact. These facts make it a good reference for comparison to Sekie Creek #2. Acid Rock Drainage / Metal Leaching Potential As per the proposal, geochemical characterization was conducted in 2005 at outcrops along Tom and Sekie Creek #2 and from the waste rock pile. In 2007 the characterization was expanded to include metal leach shake flask analysis of the adit wall. The following observations were documented:

• outcrop samples were likely acid generating (i.e. neutralization potential ratio or “NPR” < 1) and exhibited elevated concentrations of dissolved zinc, lead and copper that were above CCME;

• metal leaching concentrations were lower for outcrop samples compared to waste rock samples;

• 8 of 9 waste rock pile samples were likely acid generating (i.e. NPR < 1) and exhibited elevated concentrations of dissolved cadmium, copper, lead, nickel and zinc well above CCME;

• waste rock leachate exhibited diverse range of metal concentrations; • shake flask analysis of adit wall indicated low pH and low alkalinity; and • metal leaching concentrations observed from adit wall shake flask samples using adit

water were higher than adit discharge water; this is likely due to the increased acidity of the adit water.

Additional information was collected in relation to the adit itself. First, sludge was sampled in May, 2008 at two points from the west zone of the adit. This zone is estimated to contain 1500m3 of sludge based on dimensions of 0.75m deep by 2m wide and 1km long. The most notable observations were:

• arsenic sampled at 136 and 148 mg/kg (CCME sediment standard = 5.9 mg/kg); • cadmium sampled at 2.1 and 2.5 mg/kg (CCME sediment standard = 0.6 mg/kg); • chromium sampled at 49.9 and 67.3 mg/kg (CCME sediment standard = 37.3 mg/kg); • iron sampled at 480,000 and 484,000 mg/kg (no CCME sediment standard).

Second, it is important to note as background information that “the first 200m of the adit consists of… black pyretic argillite comprising interbedded sandstones, siltstones and shales”. Adit sample mineralogy indicated “pyrite concentrations ranging from 1.30 to 6.92% by weight.” This is pertinent to the discussion of where the adit plug is being established, considering the first 100m will remain exposed after the plug is installed. Finally, Kwong and Whitley (1992) noted an interesting dynamic at play within the Tom adit ore geology which simply shows the complexity of these reactions.

“The highest dissolved metal input into Sekie Creek #2 derives from the Tom adit… however, the acidity is relatively low associated with the discharge. This is because the ore itself carries siderite besides sulfides. Part of the acid generated by sulfide

of 85

oxidation is neutralized in-situ by the iron carbonate. However, neutralization by siderite would not lead to a near neutral pH as evidenced by the discharge pH readings of 3.4 both in the 1990 and 1991 sampling.”

Hydrology The project is within the Sekie Creek #2 watershed, a 5km long tributary of the South Macmillan River with a drainage area of 6.51 km2. This watershed includes Tom Creek, Unnamed Creek and two non-identified creeks. The adit and waste rock pile are approximately 150m northeast of the confluence of Tom Creek and Sekie Creek #2. These watercourses are typical of high energy mountain systems in that they are steep, relatively short and “streamflow response tends to be rapid”. Climate data for the Selwyn Mountains ecoregion indicates “precipitation is moderate and locally heavy with annual amounts of 600 – 700mm”; “these are the highest values for precipitation in the Yukon outside of the coastal ranges”; and finally, “the wettest months are July and August with rainfall amounts of 60 to 90mm”. Surface water – Sediments The proponent collected stream sediment data in 2006 at 19 locations along the South Macmillan River. Data indicated strong correlations between metal concentrations and upstream geology. The pH levels at sample sites was also an important factor influencing whether metals remained in solution or precipitated into sediments. Generally as pH increases metal species start to precipitate into solids and tend to bind to other particles. This data is valuable for understanding ultimately where metal contributions from the Tom adit could be deposited and what the potential implications are for creating metal reservoirs stored in downstream sediments. Groundwater – Wells The proponent installed 4 groundwater wells in order to evaluate if and how the waste rock dump was contributing to dissolved metal loading to groundwater. These wells were installed in 2005 and sampled over a three year period. Data collected indicates that surface flow and adit discharge likely infiltrate through the waste rock down to fractured bedrock where the saturated water table exists. From this point they contribute to groundwater conditions and eventually the surfacewater conditions in Sekie Creek #2. The proposal indicates that interaction between surface and adit runoff and the waste rock pile could be negatively affecting groundwater quality. Groundwater – Evidence of Seeps As per the proposal, there is evidence of a natural seep occurring below the waste rock pile and access road at an elevation of 1415 mASL (i.e. 25m below the adit). It consists of a wetted bedrock surface 1m in elevation above Sekie Creek #2. While this seep exhibits high metal concentrations its flow is below detection limits. It is possible that this seep could be originating from surface runoff flowing through the waste rock pile and exiting via an overburden/bedrock interface. Data gathered at two points at this seep indicates: very low pH ranging from 2.4 – 2.8; aluminum 67.2 – 72.8 mg/L; nickel 1.34 – 1.58 mg/L; and zinc 37.8 – 41.2 mg/L. There is evidence of two other seeps in proximity to the waste rock pile. The first, at an elevation of 1440 mASL, is associated with an abandoned drill hole south of the adit. The second, at an elevation of 1422 mASL, is associated with seasonal flow from the waste rock pile and is located at its base. Data

of 85

gathered at each indicates: pH of 5.7 and 2.85 respectfully; and zinc 5.38 and 36.8mg/L. Finally, there is evidence of two bedrock seeps further out from the adit. The first, at an elevation of 1470 mASL, is located near the W3 monitoring station on Sekie Creek #2, upstream of discharge. The second, at an elevation of 1430 mASL is located north of the adit. Data gathered at each indicates: pH of 3.2 and 2.77 respectfully; and zinc 4.38 and 4.68mg/L. Based on this information the proposal makes the following conclusions, which is included here in full text:

“…it is believed that the underground workings reside below the saturated level of the bedrock aquifer. Consequently, an increase in hydrostatic pressure within the non-flooded underground workings may potentially reduce the overall adit discharge rate.”

“Based on the water quality of the underground outflows, the flooded portion of the underground workings has significantly better water quality than the non-flooded workings. It is therefore anticipated that once the non-flooded workings become flooded, the poor water quality outflow streams, in the long terms, will also improve. This will likely produce an overall adit discharge water quality similar to the decline water quality (i.e. 12 mg/L zinc).”

“…groundwater detected within the monitoring wells located within the rock dump is likely not influenced by the hydrogeological conditions within the underground workings. Field evidenced suggests that this groundwater feature is related to ponded water that has infiltrated through the rock dump. It is for this reason that an increase rate of seepage, due to the construction of the adit plug, out the side of the mountain through the rock dump and into Sekie Creek is not anticipate.”

Toxicity – Elevated Metals and Low pH It is important to relate the results of toxicity testing the proponent conducted in 2004. Water taken from a sample site within Sekie Creek #2 just upstream of the confluence with the South Macmillan River (W8) “failed a rainbow trout bioassay (96-h LC50) with a 100% mortality rate”. Water taken from sample sites on the South Macmillan River (W9, W12 and W13) failed the same bioassay with 100% mortality. To put this in perspective they also took water upstream of the confluence on the South Macmillan River (W11) and found that the bioassay was passed with a 10% mortality rate. There are two revealing observations from this information. First, water upstream of Sekie Creek #2 and the influence of the adit had a markedly different result, though mortality was still experienced to a limited degree. Second, W13 is 8.5km downstream of the adit and yet water from this site is still killing fish with this procedure. These are the realities of what is currently happening in this area, with the adit and natural conditions each playing their role. 3.3 Biological Environment Benthic Invertebrates The proposal provides bottom fauna data collected in 2004, 2006 and 2007. In summary, benthic

of 85

diversity and abundance was relatively higher along the South Macmillan River sample sites upstream of Sekie Creek #2 as opposed to downstream of this stretch. Data improved again at sites much further downstream (i.e. 40km). Overall however, data for all sample sites was quite low in comparison to other watercourses in the Yukon. Data collected by Soroka and Jack (1983) supports this conclusion and indicates that conditions are poor for benthic invertebrates. Their data found that diversity and abundance were lower in the Sekie Creek #2 and South Macmillan River sample sites than what was found in other alpine streams. For example, “54 taxonomic groups were identified at Howard’s Pass as opposed to 11 in the Tom study”. They conclude that:

“the low diversity values can be more appropriately attributed to the low pH, cold climate, low hardness and low conductivity values seen for these waters than to pollution. As a result, the streams sampled in this study appear to have a low capability to support bottom fauna and thus fish populations.”

Fisheries As per the proposal, fisheries data was collected in August and September, 2004, and August, 2007. The 2004 data shows very limited results upstream of South Macmillan Bridge #1, a point that is 46km downstream of the adit discharge. The 2007 data found fish at only one sample point located 83km downstream of the adit discharge. There is limited historical data and none found during this assessment that would pre-date the adit installation. However there are a number of reports that may highlight some of the trends from 1974 to present-day. The Department of Indian Affairs and Northern Development (1982) reference a number of studies related to information collected in 1974 (Elson, 1974; Land Use Information Map Series, 1974; Amax Northwest Mining Co. Ltd., 1974). Together they provide the earliest recorded fisheries data that I’m aware of for the project area. In total, 13 fish species were confirmed to exist in tributaries to the South Macmillan. The survey started at Tenas Creek, just north of Ross River, and observed fish all the way up to Dewhurst Creek. No fish were detected past this point despite sampling attempts at MacMillan River #2, 3, 4, 5 and 6 and Sekie Creek #1 and #2. A survey conducted by Davies and Shepard (1981) confirms these findings. In summary:

Watercourse # km downstream of adit Detected Species Dewhurst Creek 24 Arctic Grayling Hess Creek 27 Arctic Grayling

Northern Pike Jeff Creek 31 Arctic Grayling

Northern Pike Burbot Slimy Sculpin

Unnamed Creek 35 Arctic Grayling South Macmillan River #1

37 Arctic Grayling Slimy Sculpin

Wagon Creek 39 Arctic Grayling

of 85

Boulder Creek 62 Chinook salmon Arctic Grayling Slimy Sculpin Round Whitefish

Moose Creek 71 Arctic Grayling (Davies and Shepard, 1981)

Davies and Shepard (1981) documented comments about each stream sampled. They found Sekie Creek #2 to be steep with very poor fisheries habitat. Sekie Creek #1 was noted to have fisheries habitat potential but no observed fish. South Macmillan River #2, Dewhurst Creek, Hess Creek, were found to have low productivity with an inference to water quality limitations. Jeff Creek had moderate to high fisheries habitat and productivity. Unnamed Creek, South Macmillan River #1 and Wagon Creek had moderate habitat. Boulder Creek had high fisheries habitat and productivity while Moose Creek returned to more moderate habitat. They also indicated that the South Macmillan River between Moose Creek and Boulder Creek was identified as an important spawning area for Chinook salmon and Longnose Suckers. Reid, Crowther and Partners (1982) further substantiate these findings in their report entitled “Fish Resource Survey North Canol Road”. Figure 1 below shows their fish distribution map. They indicate that Sekie Creek #1 at that time was the known upstream limit of Arctic Grayling distribution in the South Macmillan River system and that the sensitive period for this fish is from May 15 – July 31. Generally, sampling upstream of South Macmillan #2 (14km downstream of the adit) found sites to have poor habitat and sampling downstream of this point found sites to have moderate to good habitat. Fish catches in 1982 found 5 sculpins, 1 pike and 1 burbot in Jeff Creek while 1 Arctic Grayling was observed in Hess Creek. They found overwintering habitat in these creeks to be quite limited since most of the creeks had quite diminished flow or froze solid. With freeze-up generally in October they expected most fish would move down into mainstream rivers. Their report consistently recommends a construction window for the road from July 16 to April 30 in these upper stream sections. As noted by the Department of Fisheries and Oceans in supplying these reports:

“There do not appear to be any physical barriers downstream of Dewhurst Creek, the last area where fish are documented to be present. Arctic Grayling are known to move upstream during periods of high water in the spring and can travel large distances. In the absence of detailed fisheries inventory data, we must take the precautionary approach and assume that it is possible that some fish species are migrating through this area.” (Document reference 2008-0242-058-1)

Soroka and Jack (1983) had planned to conduct electrofishing along Sekie Creek #2 and nearby portions of the South Macmillan River in their study of the Tom property. Unfortunately sample sites were not conducive to this practice. Their observations indicate that the three South Macmillan sites looked suitable for fish habitat. In contrast the Sekie Creek #2 sites were observed to be unsuitable as habitat due to a lack of pools, high velocity, lack of bottom fauna and in the case of Tom creek, a waterfall that would be impassible.

of 85

Jack and Osler (1983) had also planned to conduct electrofishing in their study of the Jason Property. Sample sites were along Sekie Creek #1, Fink Creek and Barbara Creek, all tributaries to the South Macmillan River downstream of Sekie Creek #2. Again they found the sites were not conducive to electrofishing. Their observations indicate that the lower section of Sekie Creek #1 looked suitable for fish.

Vegetation The project area is sparsely vegetated, as evidenced in photo’s #1 and 2 below, and is largely above timber line. Vegetation is typical of alpine and subalpine environments and as indicated in the proposal includes: lichen-grass, dwarf shrub and shrub birch-willow communities; and subalpine fir. The lack of

Figure 1 – Known Fish Distribution (Reid, Crowther and Partners, 1982) CH Chinook (Spring) Salmon AG Arctic Grayling NP Northern Pike BB Burbot

SS Slimy Sculpin RW Round Whitefish LN Longnose Sucker O No Fish seen

of 85

vegetation around the adit is likely due to a combination of debris slides, bedrock lithology and local microclimate and microtopographic conditions. There is no recorded fire history for the project area which is logical given the sparse vegetation. An 11,568 ha fire did occur 15km south of the airstrip by road in 2004. The only other fire history for this region is a 10,353 ha fire that occurred in 1969 southeast of the 2004 fire.

Photo #1 – Northeast aspect viewing adit and waste rock.

Photo #2 – South aspect viewing Tom Creek.

Wildlife and Birds According to wildlife key area data provided by Yukon Government, the adit is located within the continuous habitat range of mountain goats. Observations supporting this were documented in 1989. I don’t believe habitat conditions have changed drastically so it is feasible that mountain goats could still be using this area. Raptors are prevalent in proximity to the project area. Golden Eagles and Gyrfalcons have been observed as recently as 2005. Locations include the South Macmillan valley just northeast of the airstrip and southeast of the Tom Creek valley. Their sensitive birth and nesting periods occur from June to August. Bald Eagles have also been observed but the general location is 15km south of the airstrip by road. Thinhorn sheep (i.e. Dall) were observed in 1990 utilizing winter habitat (October – April) west of the airstrip and the South Macmillan river. This does not pose direct overlap temporally or spatially with the project but is an indicator that sheep are in the region. Data provided by Yukon Government also indicates the presence of large polygons of excellent beaver and moderate muskrat habitat. These observations were made in 1990 and the areas are approximately 15km south of the airstrip by road and near Dewhurst Creek. Key wildlife areas are indicated in Figure 2. Other wildlife and birds in this region include:

of 85

− ungulates: moose, woodland caribou (i.e. Finlayson and Nahanni herds); − carnivores: grizzly & black bears, fisher, fox, lynx, marten, mink, otter, weasel, wolverine, wolf; − rodents: bushy-tailed woodrat, meadow jumping mouse, northern flying squirrel; − bats: little brown myotis; and − Numerous species of songbirds breeding in wetland areas.

Figure 2 – Key Wildlife Areas near the project

3.4 Socio-economic Environment First Nations As noted the nearest community is Ross River, 175km southwest of the project area via the North Canol highway. This community is home to the people of the Ross River Dena Council. The project is within the traditional territory of the Ross River Dena Council as well as the Liard First Nation, both of whom are part of the Kaska Dena Nation. The traditional territory of the Nacho Nyak Dun First Nation borders the South Macmillan River to the north and does not overlap directly with project components. The nearest interim protected First Nation land is R-42, a rural block set aside for the Ross River Dena Council. It is located on the north side of the North Canol highway. It starts near the airstrip and ends at the Yukon – Northwest Territories border. It does not appear to present any direct overlap with this project and is upstream of any watercourse impacted by the adit. Another nearby parcel of interim protected First Nation land is S-102B, a site specific also set aside for

of 85

the Ross River Dena Council. It is located adjacent the North Canol highway on the west side and is approximately 17.5km downstream of the adit and 56m from the South Macmillan river. Land Tenure and Mineral Claims This region is composed mostly of Yukon Crown land given the seasonal nature of the North Canol highway which restricts the ability for land disposition. There is a lease (105O01-003) underlying the adit area and presumably this is held by the proponent or associated with the adit in some manner. Another lease (105O01-001) acts as a reserve for the airport. There are ten other leases or reservations within a 20km radius of the adit ranging in purpose such as commercial, trapping, heritage, and environment. The Sekie Creek #2 watershed is heavily staked with active and surveyed quartz claims and most likely in association with the Tom Property. These are bordered to the west by a block of claims associated with the Jason Property. Trapping and Outfitting The project overlaps with Registered Trapline Concession #112. The proposal indicates that trapping is likely the only activity that occurs in this area in winter. Some trapping does occur in the Sekie Creek #2 watershed depending on snow levels. The project overlaps with Yukon Outfitting Concession #9. The proposal indicates that the operator does not conduct road-accessible hunting trips so there is likely limited overlap with this project. The operator uses up to 5 camps dispersed through the concession and operates in early spring and from July 31 to September 29. Hunting, Fishing and Gathering As per the proposal, at least 50 hunters use the area during the main hunting season from August to November. Male moose, male caribou, male sheep, wolverines, goats, bears, deer, wolves and coyotes are the species open to hunting during this period. Fishing tends to occur further southwest of the project area with Sheldon and Dragon Lakes being popular destinations. Stream fishing occurs as close as Hess and Jeff Creeks. Harvesting of berries, mushrooms, roots and other edible plant products is likely to occur along the North Canol highway during the summer and early autumn. Specific locations are not known though it is logical that gathering would occur closer to Ross River unless in conjunction with hunting activities.

of 85

4. CONSIDERATION OF RELEVANT WATER QUALITY STANDARDS As stated it has been compelling in this assessment to consider what water quality standard the proponent should seek to achieve through implementation of their project. A number of national and territorial standards have relevance in terms of providing context. I’ve provided an overview of four specific standards below as background information to this report. At the end of this section there is also an overview of the predicted levels and proposed long term standard. Further, Appendix II – Analysis of Water Quality Data, provides a number of tables and figures that attempt to put these standards into the context of this project. Table 1 in the Appendix provides a tabular comparison of these standards with historical adit discharge over the last 9 years, the predicted discharge and the proposed standard. This information was compiled from what was presented in the proposal. Table 2 puts this information into perspective by considering what the relative water quality will be in the nearest known fish-bearing receiving environment (Macmillan River Bridge #2 – sample site W13) in comparison to flushing and long term predictions. Finally, figures 1 – 8 provide a visual comparison the standards and predictions. 4.1 Canadian Council of Ministers of the Environment (“CCME”) The CCME standard refers generally to the Canadian Environmental Quality Guidelines developed by this council. There are two specific guidelines relevant to this project. First, the Canadian Water Quality Guidelines for the Protection of Aquatic Life which are:

“…intended to provide protection of freshwater and marine life from anthropogenic stressors such as chemical inputs or changes to physical components (e.g., pH, temperature, and debris). Guidelines are numerical limits or narrative statements based on the most current, scientifically defensible toxicological data available for the parameter of interest. Guideline values are meant to protect all forms of aquatic life and all aspects of the aquatic life cycles, including the most sensitive life stage of the most sensitive species over the long term. Ambient water quality guidelines developed for the protection of aquatic life provide the science-based benchmark for a nationally consistent level of protection of aquatic life in Canada” (CCME, 1999).

Second, the companion piece related to sediments entitled as the Canadian Sediment Quality Guidelines for the Protection of Aquatic Life. This piece recognizes that substances such as metals released into the environment may enter aquatic systems, either naturally or through human activities. Once in the system they may be deposited or become bound to particulate matter and become part of the sediment load. This sediment then becomes a long-term reservoir for these metals. They may affect benthic and fish habitat, either as part of the sediment or when released into solution, as conditions change over time. Specifically these guidelines:

“…provide scientific benchmarks, or reference points, for evaluating the potential for observing adverse biological effects in aquatic systems. The guidelines are derived from the available toxicological information…” (CCME, 2001).

As a national standard these guidelines play an important role in setting the scientific expectation for

of 85

protecting aquatic life across Canada. While the objectives have no legal standing and are not enforced, they are often used in permitting and licensing processes. Additionally, the CCME acknowledged the diversity of natural conditions across Canada and recognized that the national standard would not be applicable to all ecosystems. For example:

“a substance may be more or less toxic in site water (i.e. due to factors such as pH, water hardness, complexing agents, etc.) than it is under the range of conditions that is represented in the toxicological data set. In some cases, natural background concentrations of a substance may exceed the guideline without any apparent effect on biota. Under these circumstances, it might be necessary to modify the water quality guidelines to account for conditions that occur at the site.” (CCME, 2003).

The guidelines consequently include a process for determining site-adapted (i.e. modification of existing thresholds) or site-specific water quality objectives. This process was utilized in the Yukon to develop site-adapted water quality objectives for zinc in the South McQueston River watershed. It seems logical that a similar process is justifiable for certain parts of the Macmillan Pass region. Specifically the unique conditions associated with watersheds such as Sekie Creek #2 and Macintosh Creek. Still, in the absence of site-specific guidance considerate of unique local conditions, these CCME guidelines are an important reference for putting potential adverse effects of this project into perspective. 4.2 Metal Mining Effluent Regulations (“MMER”) The current version of the MMER applies to all new and existing metal mines in Canada. They were “designed to limit the deposit of deleterious substances into waters frequented by fish” (SOR/2002-222). The limits presented are based on a comprehensive review of national and international standards. They also “reflect the effluent quality that is being achieved by the best performing Canadian metal mines” using available technology (SOR/2002-222). Highlights of this standard include:

• effluent pH must be maintained in the range of 6.0 to 9.5; • effluent limits for arsenic, copper, cyanide, lead, nickel, zinc, radium and total

suspended solids; • mines are required to produce an effluent that is non-acutely lethal to rainbow trout; • mines are required to conduct an Environmental Effects Monitoring (“EEM”)

program; EEM will evaluate effects of mining effluent on the aquatic environment through field monitoring studies and reporting.

The Tom adit meet the criteria of having an effluent flow rate that exceeds 50 m3/day (i.e. adit = 864 m3/day or 10 L/s) and depositing a deleterious substance in any water. However the regulations do not apply in respect of mines that stopped commercial operations before the registration date of the regulations, which is June 19, 2002. This makes them more of a reference showcasing the effluent standard the Tom adit would have to comply with if it was initiated today as a production mine. More importantly it provides important context for Canadian society’s expectations of water quality from producing mines and implications for mining activity in general.

of 85

4.3 Yukon Contaminated Sites Regulations (“CSR”) Enacted in 2002 as part of the Environment Act, the CSR outlines a process for identifying contaminated sites and how to restore them to a satisfactory state. They use generic numerical soil standards and water quality standards. These standards establish the thresholds for when a site would be considered contaminated and in need of restoration. In relation to aquatic life, these regulations come into force where effluent, in this case from the adit, actually ‘daylights’ into a stream section that clearly supports aquatic life. If it was demonstrated that Sekie Creek #2 supported aquatic life then adit discharge would likely trigger this regulation and it would be considered contaminated. However, as per the background information on aquatic resources, we are aware that appropriate habitat exists quite a distance downstream of the adit discharge. At that point the adit’s negative influence on aquatic life and its habitat is diminished through dilution and complicated by high natural inputs along the way. The regulations have a provision for proponents to account for background concentrations at the point their discharge may be affecting aquatic habitat. Proposal information makes it clear that these regulations would likely not apply given the extent of natural sources of contamination. The only compelling reason to consider the CSR is when hypothesizing what water quality conditions were like in Sekie Creek #2 and downstream on the South Macmillan River prior to the adit installation. If some form of aquatic life used to be supported in these stream sections then it would help to put the adit influence into perspective. Potentially at some point the adit could have been viewed as a contaminated site in need of immediate restoration. 4.4 Water Licence Effluent Quality Standard (“EQS”) The final standard considered, and the one most relevant to this project, is the EQS currently required through the proponent’s water licence. The full details of this standard are related in section 2.1. This standard was prescribed by the Yukon Water Board as per their authority under the Yukon Waters Act. The objective of the Water Board is to:

“provide for the conservation, development, and utilization of waters in a manner that will provide the optimum benefit from them for all Canadians and for the residents of the Yukon in particular.” (Statutes of the Yukon, 2003)

They are responsible for setting the conditions for water use licences pursuant to section 13 of the Waters Act. As per section 12 of the Waters Act:

“the Board shall not issue a licence unless the applicant satisfies the Board that… the use of waters or the deposit of waste proposed by the applicant would not adversely affect, in a significant way, the use of waters… to which the application relates.” (Statutes of the Yukon, 2003)

of 85

4.5 Predicted and Proposed Water Quality Standards Initial Flushing Water quality targets for this project start with predictions for the intial flushing of the adit after it has completely flooded and begins to discharge. The proposal based this predicted range on analysis of the adit walls using a shake flask test with adit water. It represents the minimum and maximum metal concentrations observed. Maximum flushing rates will result in aluminum levels that reduce water quality at the South Macmillan Bridge #2 by as much as 5.38%. Copper will reduce water quality by 7.92%, nickel by 3.26% and zinc by 2.88%. Most of these numbers occur at low flow conditions and without the benefit of natural dilution (please refer to Appendix II, table 2). Short Term The period of time following the initial flushing is related to the “incomplete mixing and removal of oxidation products from exposed surfaces, fractures and pore spaces” prior to the system reaching equilibrium. No time line has officially been set for this ‘short-term’ interval. Predictions are based on the median metal concentrations and pH observed within adit discharge from 2000 – 2008. The impacts of this short term period are best shown in Appendix II, table 3 since the data relies on historical observed conditions in the adit discharge and receiving environment. Long Term Once the system has reached some form of equilibrium it will enter the predictions made for long term water quality. The proposal based this predicted range on the median and maximum concentrations historically observed within the Sekie Creek #2 and Macintosh Creek watersheds, or what could be viewed as the surface water background levels. The proponent has applied a 95th percentile filter to this data to create their long term vision for water quality targets. Maximum flushing rates will result in aluminum levels that reduce water quality at the South Macmillan Bridge #2 by as much as 7.13%. Copper will reduce water quality by 19.57%, nickel by 2.23% and zinc shows an improvement in water quality of up to 3.73%. Again, most of these numbers occur at low flow conditions and without the benefit of natural dilution (please refer to Appendix II, table 2). The challenge for this assessment is to understand these predictions and whether they will result in significant adverse effects. This requires consideration of a number of factors noted below.

• Confidence in the sampling and modeling that produced this data. • An understanding of the assumptions and uncertainties, how these could change the data and to

what extent. For example, one uncertainty is the seasonality of the environment and the extent to which this data captures that seasonality. Also, what key environmental components are missing, such as qualifying how sludge may influence adit discharge upon flooding and mixing. Or, how acid generation will behave in a sub-aqueous environment.

• How these predictions compare to established water quality standards as a benchmark for what the expectations are for wastewater discharge from human activities.

• Potential effects of these predictions once the project is implemented, the effects if predictions are wrong, the significance of these effects and what mitigative measures are available.

of 85

9) Potential Effects Assessment Summary and Reasons for Recommendation

1. Environmental Quality 1.1 Temporal and spatial overlap summary Project components that overlap with environmental quality include:

• transport, handling and storage of petroleum products 1.2 Effects characterization and significance determination Transport, Handling and Storage of Petroleum Products The use of petroleum usually implies some risks for fuel spills. In this case the project will be using 4000 L. Any use of pumps adjacent to water bodies has the potential for chemical contamination of water resources associated with spillage/leakage of petroleum hydrocarbon fuels and lubricants. Additionally, improperly maintained equipment can also result in drips, leaks and/or breakdowns and may result in spilled products into the environment. Petroleum spills can potentially harm the soil, wildlife, vegetation, contaminate ground water and create a fire hazard resulting in the injury or death to the above components within this ecosystem. The potential effects are most likely to occur as the result of accidents or malfunctions related to the transportation, storage or use of such products. I have reviewed the following existing legislation:

• Quartz Mining Land Use Regulation – Schedule 1 Operating Conditions − section G - Petroleum fuel and hazardous substances; − section H - Spills and spill contingency plans; and − section I - Use of vehicles.

In my opinion this legislation sufficiently regulates these activities and adherence to it will ensure that there are no significant effects to environmental quality. 2. Water Resources 2.1 Temporal and spatial overlap summary Aside from water used for the camp, the main project component that involves water or could affect it is the underground and aboveground work related to the adit (e.g., for construction make-up water, dust control on roads, construction of the sludge containment facility, lined discharge channel and installation of the partial waste rock cover). 2.2 Background Information

of 85

Hydrologic and Hydrogeologic Conditions Sekie Creek #2 flows only during the ice-free seasons and due to the relatively small watershed sizes some of the smaller tributaries flow intermittently. Peak flows are associated with Spring freshet and infrequent high magnitude rainfall-generated flows. Annual flows are at their minmum during later summer and extened dry periods. Minimal streamflow data exist and consists of flow measurements taken during water sampling activities. Continuous flow data is not available. Although there are four groundwater monitoring wells at the site, they are installed only on the waste rock dump and only one of these wells may reflect saturated conditions of the bedrock. In general, conditions are not well established nor is the effect of the proposed project on the groundwater regime. Specifically the effect of plugging the adit and raising waters in the adit by 20 m. The proponent developed a hydrogeologic concept for the site that includes the boundary between saturated and unsaturated groundwater at the elevation of the adit floor at its opening. This makes the following assumptions:

• flooded workings exist below this general elevation while unflooded workings lie above this elevation;

• a moderate gradient into the hillslope parallels the main West zone adit floor gradient; • adit discharge is sourced from leaking fractured bedrock.

Based on the September 2008 adit survey, the majority of adit discharge is sourced from leaking fractures located where the adit (at 1444 m in elevation) goes under the tributary to Sekie Creek #2 at 1560 m in elevation. Thus, in this case there is an apparent direct connection with surface waters. The adit discharge has been recorded infrequently over the last eight years (i.e. only 18 measurement dates). Only during summer 2000 were a significant number (i.e. over 50 daily measurements) of flows recorded. The 2000 data set indicates a steady increase from ~7 L/s to a peak flow of ~12 L/s in mid-summer, followed by a steady decline back to ~7 L/s. Thus, the data indicates a seasonality of flow, with perhaps the total volume of flow associated with the amount of infiltrated snowpack and/or early season rains. There did not appear to be any relationship between adit flow and precipitation events, suggesting that the bulk of the recharge may occur primarily in the spring. There are still, however, questions related to groundwater levels and groundwater hydraulics.

• Will the increased water pressure from the adit plug increase the infiltration of water north of the adit and into the waste rock pile?

• The relatively small seasonality of flow (i.e. compared to that observed in local surface streams),

suggests there is a non-static condition in the ground, and that groundwater levels will vary seasonally. Further, the time for filling of the adit workings does not consider bedrock fracture porosity, which would require more time to fill, thereby extending the flooding period beyond 30 days. If the adit workings do not fill before freeze-up then monitoring the initial effects of the flushing stage will become more difficult.

• The amount and nature of change in the groundwater flow regime after flooding is only generally

understood, and groundwater levels prior to adit development are not known at all. Some

of 85

anecdotal information from miners (i.e. observations of excessive volumes of water from seeping fractures when the adit was first opened) suggests that the bedrock was fully saturated above the adit elevation prior to development. Thus it is likely that the adit drained a significant portion of the bedrock above and horizontally adjacent to the workings. The extent of this “basin” (as opposed to a cone) of depression is unclear, but it is assumed that the plug will have the effect of re-filling some of the depressed zone – thereby changing hydraulic gradients, flow directions and flow patterns in the interconnected bedrock fractures. Although as mentioned in the response, it is likely that a “localized drain” will develop in the adit downstream of the plug, with the available information provided the following matters are not clear:

− what the extent and effect of this drain will be; − whether seep flow rates (e.g., west of the dump) will change; and/or − whether new seeps may develop (i.e. as stated in the response: “it is unclear whether the

source of [the seep] water is related to the deep groundwater flow system – the underground hydrogeological flow regime controlling adit flow”).

• Current seepage rates are described as being extremely low, although flow data does not yet exist

for the majority of the seeps.

• Monitoring of the hydrostatic pressure behind the plug is planned. The frequency should be sufficient to test filling rate hypotheses, detect leaks in the plug, and provide sufficient time to develop contingencies for modifying monitoring schedules and timing.

2.2 Effects characterization and significance determination Underground Work – Construction of Adit During the construction stage of the adit plug (including preparation of adit walls and installation of pressure relief drift), surface water and/or groundwater balances will not be measurably changed, nor will groundwater table elevations or surface water channels be affected. The adit flow will be conveyed (piped) for a short time (perhaps a week at most) through the area of plug construction to at first the sludge containment facility (until the sludge berm and lined discharge channels are completed), and then to the lined discharge channel. During the period of diversion to the sludge pond, the flow of Sekie Creek #2 will be reduced by the amount of the adit discharge (adit flow on September 11, 2007 was 8.4 L/s, or only 5.3% of the ~157 L/s in Sekie Creek #2). This reduction in flow would not be considered significant even if Sekie Creek #2 had a viable aquatic ecosystem, as it represents a small part of the observed variation in seasonal flows.

Mitigation • No mitigation is required.

Direct Use of Water Water use is estimated to require a maximum volume of 120 m3 over the life of the project. Due to the limited volume of water required for the proposed project water withdrawal from the South Macmillan River is not considered to have any direct adverse effects to water resources.

of 85

Underground Work – Flooding of Adit Workings This stage begins at the completion of adit construction when the workings behind the adit plug begin to fill and continues until water levels reach the relative elevation of the pressure relief valve. Water levels are predicted to rise 20 m behind the adit plug, until reaching the level of the pressure relief valve. Assuming an average adit flow rate of 10 L/s, the filling is expected to take 30 days. The period of filling may vary from 25 to 40 days, though, as the adit flow rate varies with season. The flow in Sekie Creek #2 will be reduced by approximately 5-6% of the average annual flow at W6 and less (only 3%) at W8 or at the mouth of Sekie Creek #2 where it joins the South Macmillan River. As water levels in adit begin to rise, groundwater levels in the adjacent rocks will also rise. As described above, the amount and nature of change in the groundwater flow regime after flooding is only generally understood. In general, it can be assumed that the plug will have the effect of re-filling some of the existing bedrock fracture porosity, thereby changing hydraulic gradients, flow directions and flow patterns in the interconnected bedrock fractures. At this time, it cannot be reasonably predicted how this will affect seep flow rates along Sekie Creek #2 upgradient, adjacent to and downgradient of the waste rock dump, and/or whether new seeps may develop. The potential for flooding of the adit to create new seeps and thus uncontrolled, and to some extent unknown, point sources of adit discharge is unknown at this time. However, employing the precautionary principle I believe the potential effects are significant and adverse. In addition to seeps, as I understand it there is at least one exploration drill hole in proximity to the Tom adit with demonstrated outflow of 0.57 L/s. It is located in Sekie Creek #2 southeast of the adit and 128m above the west zone incline. The proposal indicated it was not know to what degree this hole was connected to the adit workings. Existing drillholes that are potentially connected to the flooded adit could bring further uncertainty to the project design. They may become point sources of adit discharge or otherwise affect the attempts at creating controlled discharge from the adit. As noted, the drill hole is quite a distance above the workings but it is unknown what its total depth is. Creating additional points of contamination, and the resulting implications for interacting with the waste rock pile, are counter-intuitive to the overall intentions of this project. In my view the potential effects are significant and adverse when considering that the solution, as put forward by Environment Canada, is relatively simple.

Mitigation: • Complete adit construction early enough in year to allow for monitoring to begin during ice-

free season, and to accommodate slow or rapid filling periods. Rationale: This will allow more lead time to monitor conditions and implement adaptive management as needed. Once freeze-up and low-flow conditions occur in late fall the opportunity to monitor and thus understand conditions on-the-ground is very limited. The adaptive management relies on field information to be effective.

• Monitoring of head behind the adit plug is planned; continuous recording of head is

recommended to facilitate estimation of volumes and ascertain whether bedrock fractures are collecting a large proportion of the adit inflow.

• Seepage flow rates should be measured whenever and as often as logistically feasible to

establish a baseline against which future flow rates (after flooding has been completed) can

of 85

be compared. This would enable one to develop reasonably accurate estimates of the seep flow rates as a baseline to help evaluate whether the proposed project will affect them.

Rationale: This type of information is critical for the Adaptive Management Plan.

• Remediate all drill and bore holes on the Tom property that have flow. Remediation should

be designed to stop this flow (e.g. appropriate plug techniques). Emphasis should be on those holes that are below the predicted flood elevation for the adit workings.

Rationale: Plugging and otherwise remediating known drill and bore holes will reduce the potential adit discharge to occur from uncontrolled point sources.

Underground Work – Remaining Exposed Adit Walls Due to project design and the need to install the plug in a secure area, approximately 90m of adit will remain exposed to outside conditions via the north portal. The geology of this portion of the adit is conducive to ARD/ML. By default the design of this project will ensure that this section continues to be exposed to favourable ARD/ML conditions. I don’t believe this will contribute significantly to metal concentrations beyond what the adit will be discharging. I also appreciate why this section can not be sealed in the manner chosen for the rest of the workings. However I think it is important to at least monitor this section. Over time the adit discharge will hopefully improve – it would be unfortunate if this improvement was reduced because of this potential issue. Monitoring will help us understand whether this is an issue or not.

Suggestion: • Proponent shall monitor the remaining exposed portion of the adit post installation of the

plug. Sampling will determine the rates of metal release, concentrations and potential loading contributions to adit discharge. Rationale: Once the plug is installed it will be important to distinguish where exactly metal and acid contributions are coming from. One of the ways to monitor is through the “Minewall technique” developed for the former Canadian Mine Environment Neutral Drainage (MEND) Program. As per documentation available “Minewall uses a general mass-balance approach for all inputs and outputs of water and chemistry, plus the water level and chemistry of any accumulating mine water. It is a flexible tool for forecasting geochemical conditions in open-pit mines or underground workings” (Morth et al. 1972). It relies on 4 steps:

1. Obtain unit-area reaction rates from Minewall stations. 2. Compile lateral, inclined and vertical exposed surface areas by elevation in

underground workings based on site-specific survey data. 3. Estimate fracture intensity or design the blast intensity in order to obtain the ratio of

reactive surface area to exposed surface area, and include other rock surface like waste rock.

4. Estimate loadings that will be released on a regular or periodic basis, or retained if/until that portion of the wall is submerged.

of 85

It is important to note that the extent of this issue is not isolated to the rock face of the adit. Fractures naturally present or created from blasting and excavation increase the reactive surface area. Morth et al. (1972) found fractures oxidizing up to 15m behind the visible mine wall. Use of this technique will inform the decision-making process in relation to adit discharge as well as any adaptive management required.

3. Aquatic Resources 3.1 Temporal and spatial overlap summary The main project component that overlap with aquatic resources are:

• underground work • aboveground work

3.2 Effects characterization and significance determination This section will explore:

• effect pathways to be considered (i.e. manner in which project activities may cause an effect); • contaminants of concern; • specific activity effects and mitigations; and • adaptive management plan.

3.2.1 Effects Pathways There are three effect pathways to be considered in relation to aquatic resources as follows:

• Water Quality – Effluent discharges attributed to this project containing elevated concentrations of certain contaminants, particularly metals, have the potential to elevate metal concentrations and increase turbidity in project area receiving waters.

• Sediment Contamination – Elevated concentrations of metals in the receiving waters may

result in greater concentrations of such contaminants being deposited and accumulating in surface water sediments.

• Aquatic Life – Elevated metal concentrations in the receiving environment (surface water and

sediments) may also affect the life function and productivity of aquatic plants and animals (i.e. invertebrates and fish).

Water Quality The Macmillan Pass in east-central Yukon (Figure 1) near the border with the Northwest Territories, is a

of 85

highly mineralized area. The significant presence of metallic minerals in the MacMillan Pass area is reflected by the naturally elevated metal concentrations in both the soil and water (Soroka and Jack 1983, Kwong and Whitley 1993). The various historical mine workings located along the mountainsides are subject to the hydrological regimes of the area and carry contaminants down the mountainsides into the streams, creeks, and rivers in the valley below. Greater volumes of effluent and effluent with high concentrations of contaminants reaching receiving waters may lead to increased loading to receiving waters and potential significant adverse effects to water quality. Further, historical anthropogenic activities on the property have over time degraded the water quality in Sekie Creek #2; these effects have contributed to water quality degradation in the South Macmillan River. Also, accidents or malfunctions leading to failure of remedial systems (i.e., adit plug) and treatment infrastructure (i.e., sludge containment), flushing of adit walls, or inadequate storage of waste rock could lead to discharge water that has elevated concentrations of certain metals and suspended sediment, and elevated turbidity. Turbidity is a measure of lack of clarity or transparency of water caused by biotic and abiotic suspended or dissolved substances including sediment. The higher the concentration of these substances in water, the more turbid the water becomes. Turbidity also affects water chemistry, rendering it unsuitable for aquatic organisms and impacting the existence of downstream aquatic resources. These impacts include, but are not limited to, an increased temperature and reduction in oxygen content affecting the health of benthic invertebrates and fish. In general, the deposition of fine sediment in stream ecosystems is detrimental to aquatic organisms. In the case of an adit breach or sludge containment facility failure the sludge would potentially be released as fine particles becoming suspended in the receiving water course. Sediment Contamination Elevated concentrations of contaminants and metals conveyed downstream to receiving waters may result in greater accumulations of these contaminants in channel sediments. Increased volumes and flow of water entering water courses may transport contaminants as suspended solids. Most particles will settle out as they are transported downstream depending upon particle size velocity of water and water quality parameters at point of deposit. When untreated or non-compliant adit flows containing relatively high metals concentrations in solution enter watercourses, they ultimately precipitate and accumulate in downstream sediments. Aquatic life Aquatic resources are susceptible to a number of different contaminants that may be introduced to the environment as a consequence of mining projects. Acid rock drainage and metal leaching (ARD/ML) in particular can mobilize and introduce a wide variety of heavy and trace metals into aquatic environments that, in sufficient concentration, can become toxic to aquatic life. Heavy metals (e.g. iron, aluminum, manganese) can increase the toxicity of water and act as metabolic poisons. Trace metals (e.g. zinc, cadmium, copper) are toxic at extremely low concentrations to fish during all their life stages, and may also suppress algal growth and affect benthic invertebrates in aquatic ecosystems. ARD produces acidity which lowers the pH of water it comes into contact with. Acidity, in turn, influences the solubility of metals, which typically become more soluble and then mobilize into acidic water. The mobilization of metals into water and subsequent introduction into the receiving environment can result in the disruption of aquatic ecosystems (e.g. benthic invertebrate type and distribution, food sources for fish, biomass reductions). This disruption can range from isolated

of 85

nuisances to severe water quality impacts affecting large volumes of groundwater and many kilometers of a watercourse. The lower the pH, the more severe the potential impacts on aquatic life. Acidic water can become corrosive and unable to support many forms of aquatic life. For instance, low pH conditions can alter calcium metabolism and protein synthesis, affecting the growth of fish. Low pH conditions may alter gill membranes or change gill mucus resulting in death due to hypoxia. Generally, most fish are affected by acidity when the pH is 5.5. or below. A study of the distribution of fish in Pennsylvania streams affected by acid rock drainage (Cooper and Wagner, 1973) found fish severely impacted at pH 4.5 to 5.5. These investigators reported complete loss of fish in 90% of streams with waters of pH 4.5. The extent to which an aquatic ecosystem can moderate acidic water is dependent upon flow (dilution rate), pH, and buffering capacity of the aquatic environment. When the pH of acidic water rises, iron precipitate commonly forms which decreases oxygen as it forms, and can coat fish gills and body surfaces, smother eggs, and fill in crevices in rocks making the substrate unfit for habitation by benthic organisms. The worst case scenario involves high volumes of low pH (acidic) water discharge, with high concentrations of dissolved metals that drain into lightly buffered streams and produce accumulations of precipitated iron or aluminum. Elevated levels of contaminants and metals in sediment and water courses may lead to increased levels in aquatic vegetation. Aquatic vegetation living in contaminated water and acquiring nutrients from stream sediment with elevated metals and other contaminants could absorb and accumulate those substances. Aquatic vegetation has varying tolerance levels for contaminants depending on individual species. However, high metal concentrations may harm or kill species that are more sensitive leading to local elimination and reduced ecosystem diversity. Species diversity is the basis for ecosystem function and a change in aquatic vegetation resulting in local elimination of particular species and ultimately decreased ecosystem diversity would be an adverse and significant effect. Additionally, microscopic organisms that are living amongst the benthic sediments ingest inorganic matter converting it into organic, thus beginning the bio-accumulation of metals in biota as each species is ingested by the next.6 Benthic organisms make an excellent indicator of stream health because of their relative immobility compared to fish and can provide more accurate site data. In extreme circumstances benthic organisms will not be present because they cannot survive in an environment with high metal concentrations. Factors classically characterizing a healthy benthic community include a high taxonomic richness; an even distribution of numbers of each species; and the presence of species typically sensitive to habitat disturbances. 3.2.2 Contaminants of Concern Aquatic communities are affected by both natural in-stream habitat characteristics and introduced characteristics, such as point and non-point pollution. CCME provides freshwater aquatic guidelines that reference various water quality parameters. Upstream water quality not meeting these guidelines may result in bio-accumulations of adverse metal concentrations within body tissues of aquatic organisms. Certain metals have the further potential of biomagnifying up the food chain and depending on their half-life could be quite persistent. Evaluation of data indicates that most of the aquatic health issues in this situation relate to copper, nickel and zinc.

of 85

Eight metals (aluminum, arsenic, cadmium, chromium, copper, lead, nickel, and zinc) have been characterized below in terms of their potential effects to aquatic resources at a contaminated level. These were selected since five of them are listed in the current water licence EQS and all of them display elevated levels. It is important to note that they do not constitute the complete list of water quality parameters that may be elevated and potentially affect aquatic resources. In terms of what these contaminants may be of concern to, consideration has been given to primarily to Arctic Grayling and where possible benthic invertebrates. Aluminum Most aluminum compounds are insoluble except in low pH conditions. The most prevalent form is Al+3 when pH is less than 5. This form is also the most bioavailable and toxic. Aluminum in low pH conditions interferes with phosphorus metabolism in plants; causes loss of Na+ and Cl- through fish gill membranes and inhibition of an enzyme required for Na+ transport; and compounds precipitate on fish gill membranes, inhibiting exchange of O2 and CO2, resulting in asphyxiation (Nieboer et al., 1995).

Arsenic Arsenic is most toxic in the inorganic form. In terms of metal species toxicity, AS+3 is formed under anaerobic conditions in sediments and groundwater and is more mobile and soluble. This makes it more toxic than AS+5 which forms in aerobic surface conditions (Bradl, 2005). With this project my impression is that we will be dealing with the more common aerobic form when it comes to aquatic habitat. The degree and rate of uptake depends on phosphorus, which interacts with arsenic and competes for sorption sites (Gomez-Caminero et al., 2001). Arsenic has a high affinity for proteins and lipids making it readily bioconcentrated (Bradl, 2005). Arsenic compounds cause acute and chronic effects in individuals, populations and communities at concentrations ranging from a few micrograms to milligrams per litre, depending on species, time of exposure and end-points measured. These effects include: lethality; inhibition of growth, photosynthesis and reproduction; and behavioural effects. Arsenic-contaminated environments are characterized by limited species abundance and diversity. If levels of arsenate are high enough, only species which exhibit resistance may be present (Dameron, C. and P.D. Howe, 1998). Cadmium Cadmium is in the same family of the periodic table as zinc and can replace zinc in some enzymes. The CD+2 species is the most bioavailable (Bradl, 2005). Cadmium has a high bioconcentration factor and has been observed to biomagnify up food chains. With a half-life of 20-30 years it is persistent in organisms (Wright and Welbourn, 2002). It affects aquatic organisms in a number of ways. For example, it causes skeletal deformities by replacing calcium in bones, impairs growth and physical functioning of certain organs and high concentrations may affect gill functioning (Bradl, 2005). Chromium This metal has a high biocentration in benthic or bottom-dwelling fish but no evidence has been found for biomagnification. Its toxicity increases with temperature which is not likely to be an issue for this project given the high alpine environment. However toxicity does increase as pH becomes more acidic since it promotes transition to the most toxic form, Cr+6. This species of chromium has been found to inhibit algae growth at 62ppb and fish growth at 16ppb (Wright and Welbourn, 2002).

of 85

Copper In the aquatic environment the concentration of copper and its bioavailability depend on factors such as: water hardness and alkalinity; ionic strength; pH and redox potential; suspended particulate matter and carbon; and the interaction between sediments and water (World Health Organization, 2007). Copper is moderately soluble but does tend to bind to sediments and organic matter (Bradl, 2005). Bioaccumulation of copper from the environment occurs if the copper is biologically available however it does not biomagnify (Wright and Welbourn, 2002). An important factor in assessing the hazard of copper is its bioavailability. Adsorption of copper to particles by organic matter can greatly limit the degree to which copper will be accumulated and elicit effects. Other cations and pH can also significantly affect bioavailability (World Health Organization, 2007). Tolerance to copper has been demonstrated in the environment for phytoplankton, aquatic and terrestrial invertebrates, fish and terrestrial plants (Dameron, C. and P.D. Howe, 1998). Copper has been shown to exert adverse reproductive, biochemical, physiological and behavioural effects on a variety of aquatic organisms. Copper concentrations as low as 1-2 µg/litre have been shown to have adverse effects on aquatic organisms (World Health Organization, 2007). Juvenile coho salmon exposed to 20ppb dissolved Cu for 30 minutes resulted in an 82% reduction in olfactory response (McIntyre et al., 2008). However large variations due to species sensitivity and bioavailability must be considered in the interpretation and application of this information (World Health Organization, 2007). Lead The uptake and accumulation of lead by aquatic organisms from water and sediment are influenced by various environmental factors such as temperature; salinity; and pH. In contaminated aquatic systems, almost all of the lead is tightly bound to sediment. The lead uptake by fish reaches equilibrium only after a number of weeks of exposure. Lead will bioconcentrate and accumulate in skin, bones, kidney, and liver of fish as opposed to their muscle tissue, however it will not biomagnify (Wright and Welbourne, 2002). Exposure pathways include absorption through gills and consuming/ingesting lead-contaminated water, prey and sediments (Wright and Welbourne, 2002). Effects are wide-ranging. With algae, lead > 500ppb has been found to inhibit enzymes needed for photosynthesis, reduce water absorption, interfere with cell division and inhibit growth. With fish, lead >50ppb has had negative effects on growth and gill function, muscular and nerve degeneration (Taub, 2004). Young stages of fish are more susceptible to lead than adults or eggs. Typical symptoms of lead toxicity include spinal deformity and blackening of the caudal region. The feeding ability of fish was affected with severe spinal curvature. Avoidance behavior of fish occur at lead concentrations of 10-100 mg/litre. Juvenile stages are generally more sensitive than adults, but eggs are often less sensitive because lead is adsorbed onto the egg surface and excluded from the embryo (World Health Organization, 2007). Nickel This metal bioaccumulates in aquatic organisms but does not biomagnify up the food chain. The specific toxicity can be masked by the presence of other metals. Levels of Ni at 0.5-2.0 ppm have shown reduced growth rates in algae. Nickel may also delay hatching and increase mortality levels of fish embryos. Adult fish and benthic invertebrates have also displayed decreased growth (Environment Canada, 1994).

of 85

Zinc Zinc can be present in water in dissolved or solid form and tends to be adsorbed to sediment. Only dissolved Zn+2 is bioavailable but it does not biomagnify. Bioavailability is affected by biotic and abiotic factors such as: organism age and size; prior history of exposure; water hardness; pH; dissolved organic carbon; and temperature (Simon-Hettich et. al., 2007). Environment Canada has indicated that a site specific water quality objective, as per the CCME for zinc, is “modified by hardness in the water, and that hardness is reduced during freshet which is the time where maximum load and minimum protection of aquatic life is occurring”. Consequently, the management of zinc must be conducted on a site-specific basis (Simon-Hettich et. al., 2007). Zinc concentrations of > 20 µg/litre have been shown to have adverse effects on aquatic organisms (Simon-Hettich et. al., 2007). Zinc has been shown to exert adverse reproductive, biochemical, physiological and behavioral effects on a variety of aquatic organisms (Simon-Hettich et. al., 2007). For example, it accumulates and may cause structural damage to gills, liver and kidneys. It does not accumulate in muscle tissue making it similar to lead in this matter. Rainbow trout have displayed stress responses such as hyperactivity, increased blood cortisol and metallothionen synthesis in the liver (Taub, 2004). The presence of zinc increases the toxicity of cadmium in benthic invertebrates. Community effects include altered benthic species and therefore altered fish species and decreased spawning activity leading to reverberating population effects (Taub, 2004). Scientific studies suggest that zinc contamination can profoundly affect the nature of the benthic community recruiting. Aside from aluminum and iron, zinc is the most prevalent contaminant in the adit drainage water and the metal of most concern. 3.2.3 Activity Effects and Mitigations Effects to water quality and ultimately aquatic life are typically measured by comparisons to standards, including CCME or site specific effluent quality standard (refer to part 8 – background information, section 4). These standards become the point of compliance in a water license. In this case, due to the naturally low pH and high metals concentrations in Sekie Creek#2, CCME is not realistic and the existing EQS does not fully account for the naturally background levels as observed in, for example, MacIntosh Creek of the adjacent watershed. The proponent has proposed that the long term standard be equivalent to the 95th percentile of the background data set collected between 2000 and 2008, and which was calculated from stations in Sekie Creek #2 and Tom Creek both upgradient of the adit discharge (W2, W3, W3B, W3C, Unnamed Creek, T2, T3), two tributaries joining Sekie Creek #2 downstream of the adit (T4 and T5) and W9 (MacIntosh Creek). This data set however does not include much older background data collected in 1981, which suggest lower concentrations of both Zn and Cu, as well as lower hardness at that time (Appendix II - Figure 9). Lower relative concentrations were also observed in South Macmillan River in 1981, and concentrations of Zn, Cu and hardness appear to have increased since then based on samples collected in 1981, 1990, 2000 and 2005 (Appendix II - Figure 10). Thus, it is not clear whether the 95th percentile of the 2000-2008 data set are representative. Further, it is not clear whether this data set equally represents observed seasonal variations, or whether each station is equally represented. Context on the baseline conditions, known fish and benthic invertebrate resources and how contaminants of concern affect them has been provided earlier in this report. At this point we must turn

of 85

our attention to the activity effects which are best understood when considering the proposed project in its phases. This section describes the predicted effects on pathways from each activity in the following three phases: construction phase, flooding/flushing phase, and long-term monitoring phase. 3.2.3.1 Construction Phase Underground Work - Construction of Adit Plug, Pressure Relief Valve and Adit Sludge Berm Use of explosives Explosives will be used for the preparation of the adit walls for plug installation and to construct the pressure relief valve. A byproduct of using explosives to create the new bypass pressure relief drift is ammonia and this poses a potential for ammonia to become a contaminant of concern in water discharged from the site. According to the CCME: there is extensive “data available on the toxicity of ammonia to aquatic organisms, in particular acute, chronic and sub-lethal effects of ammonia in fish”; and the speciation of ammonia into ionized and un-ionized forms is influenced by pH and temperature and un-ionized ammonia is known to be more toxic due to the greater mobility of un-ionized ammonia through biological membranes. The correlation of these factors indicates that as pH and/or temperature increase, the percentage of un-ionized aqueous ammonia also increases. The CCME indicates that “aquatic community ecological risk criteria on the impact of ammonia at the community level of both invertebrates and fish indicated that 5% of the species in an aquatic community would exhibit a 20% reduction in growth, or reproduction at an un-ionized ammonia concentration of 0.041 mg/L. Based on this type of information the guideline for un-ionized ammonia for the protection of aquatic health has been set at 0.019 mg/L while the guideline for total ammonia is presented as a range of values dependent upon temperature and pH. This is not considered to be a significant effect due to the relatively low volumes of explosives required. However potential effects to aquatic resources could be reduced if blasting was conducted in dewatered areas. I will put this forward as a reasonable suggestion to improve the project design and reduce this effect.

Suggestion: • Blasting to be completed in dewatered area.

Direct Use of Water The physical act of removing water from a waterbody via pump, as in the case for water withdrawals associated with camp use and underground work, has the potential to cause death or injury to fish if they come into contact with an operating pump. Individual fish may become entrained or entrapped. Also the removal of water may result in a reduction in suitable habitat. These effects are considered to be significant and adverse.

Mitigation: • All water withdrawals from stream reaches designated as fish streams must be screened to

prevent the entrainment and/or entrapment of fish.

Rationale: This is a standard measure that effectively deals with this effect. It is intended to complement the more specific recommendation made by the Department of Fisheries and

of 85

Oceans.

Sludge Management There is a considerable volume of iron hydroxide sludge in the West zone and the underground workings. Based on an adit exploration survey completed in September 2008, there is an estimated 1500 m3 in the West zone. The east zone is similar. There is also a 500 m main adit area that runs from the portal to the junction of these zones that also has sludge. Further, there is a limited amount of sludge that was observed in the decline. Two samples of the sludge indicate very low pH, very high concentrations of iron (i.e., ~480,000 mg/kg), and the presence of arsenic, cadmium and chromium that exceed the Interim Freshwater Sediment Quality Guidelines (ISQG). Iron, arsenic, cadmium and chromium in the sludge also exceed the Probably Effects Levels (PEL). When undisturbed, the sludge forms a hard surface over which the adit water flows. However a lot of this has since been broken up and is likely mobile from when the adit was explored in September. Disruption of Sludge The adit plug will be installed ~100 m in from the portal opening. The physical act of entering the adit to install the plug, construct the sludge berm and the pressure relief drift will disturb the sludge, allowing it to enter the water column, exit the adit and contribute sediments, turbidity, metals and acids to Sekie #2 Creek. The increased loading would be considered significant and adverse. Construction and Use of Sludge Containment Facility To handle this sludge the proposal calls for the construction of a 1.0 m high temporary rock fill plug (berm) on the upstream side of the adit, to prevent sludge from entering the work zone and exiting the adit portal. Further, a lined containment pond (60 mil high density polyethylene) will be built on to the top of the existing waste rock pile to contain the sludge. The containment facility is planned to be used only during the construction phase and has a minimal design capacity of 1200 m3. The pond has been sized to contain the sludge in the tunnel as well as the entire flow of water expected to be discharged through the tunnel during the construction of the berm. The pond may be undersized if the time required to complete all the construction activities has been underestimated, the settling rate of the sludge is overestimated, or the flow rate from the adit is underestimated. This will result in pond overflow into to Sekie Creek #2 prior to settling of the sludge and contribute to creek contamination. The increased loading would be considered significant and adverse. Further, it has been assumed that the sludge will completely drain from the entrance of the adit during the construction stage; however, this may be a protracted process. Once construction is complete, the plan is to divert the adit discharge back into the creek. Any disturbed and potentially mobile sludge remaining in the adit (downstream of the plug) could then enter the creek directly. The increased load of iron and other metals from the sludge would be considered significant and adverse.

Mitigation: • A contingency plan will be developed to handle any volumes of sludge and water above

design capacity, including the capability to easily increase facility dimensions.

Rationale: This will reduce the potential for the pond to overflow prior to sludge settling.

of 85

• Due to the uncertainties in discharge water quality, a basic water treatment system should be developed and be ready to install to intercept the adit discharge and ensure that water quality entering Sekie #2 meets the background water quality targets.

• A shake test, similar to that carried out on the adit rock wall samples, will be conducted with

representative sludge samples to determine the effect on adit drainage water chemistry and ultimately on the three effect pathways in the adjacent watercourses.

Installation and Performance of Sludge Containment Facility The liner could sustain damage during installation on the coarse waste rock, or over time due to freezing and thawing processes. A damaged liner could result in water and sludge draining through the rock pile, exposing new surfaces to ARD/ML processes, and contribute to further acidification and elevated metal concentrations in the creek. The increased ARD/ML would be considered significant and adverse.

Mitigation: • Periodic observations and sampling of seeps (if present) at the base of the waste rock pile.

• Adaptive Management Plan will include a plan for addressing the presence of seeps and water

affected by ARD/ML. Construction of Waste Rock Cover The waste rock pile will only have 75% coverage; the slopes will not be capped. Although runoff from the surrounding terrain will be diverted off the cap, precipitation and runoff from the cover can enter into the rock pile along the slopes. Further, any increases in groundwater levels could cause groundwater to move through the bottom of the bottom, thereby providing a mechanism to mobilize acidic water and any leached metals. Thus, it is possible that water will flow through the waste pile and result in increased ARD/ML, more acidic conditions, and higher metal concentrations in Sekie Creek #2. The long-term integrity of the cover is expected to be high, however, it is unclear how the cap will perform at only 75% coverage – degradation of the cap could be initiated by erosion of the cap fringes and then work inward. These effects are considered significant and adverse.

Mitigation: • The surrounding terrain will be graded to redirected flow into the lined discharge channel.

• Monitor the conditions and size of the waste rock cover. Develop a plan to maintain and

repair the cover in relation to long-term degradation or short-term exceptional events (i.e., flooding, debris flows, avalanches).

• Adaptive Management Plan will include provisions to increase cover area and minimize or

eliminate runoff into the pile slopes. Construction of Temporary Facilities The construction and use of roads, storage facilities, temporary buildings and camps will disrupt soils and vegetation leading to erosion and sediment transport to receiving waters. Any activities that lead to erosion and sedimentation in the Sekie #2 Creek, especially during upset conditions (e.g., intense rainfall events, break-up season) would be considered significant and adverse. General sediment control

of 85

plans call for implementing standard and site-specific best management practices (“BMP”) to control erosion and sediment transport.

Mitigation: • Work that will disturb soils will be stopped during periods of high precipitation.

• Appropriate erosion and sediment control best management practices will be developed and

followed.

• Adaptive Management Plan will include periodic observations and monitoring of appropriate parameters, followed by continued assessment to address any unforeseen or low probability events (i.e. hillslope failures, avalanches, debris flows).

3.2.3.2 Short Term Flooding / Flushing of Adit Workings Once the adit plug is completed, water will begin flooding the mine workings. The mine walls of the workings have been subject to potentially continuous physical and chemical weathering since they were first opened over 30 years ago, exposing surfaces for oxidation and ARD/ML processes. Leaching has been a transit mechanism for metals and acid to reach the adit waters flowing to the receiving environment. The variations of rock surfaces exposed (i.e. direct face and fractures), mineralization, acid generation potential, neutralization potential, weathering and leaching throughout the adit workings has likely yielded a range of ARD/ML surface conditions. The walls (which have an acidic film and are coated with dissolved and precipitated metals) and sludge (which is disturbed in places and contains high concentrations of iron as well as other metals above IFIQ standards) will then begin reacting with the flooding water. The solution will continue to develop until the flooding has reached the relative height (20 m) of the pressure relief valve. This process is estimated to take 30 days. Predicted concentrations of the initial discharge will be higher during peak, median and low flow conditions. The effect is predicted to be the worst during low flow season, although the maximum effect is only ~11% worse (for zinc, for example) than the 95th percentile (from the 2000-2008 data set). These predictions, however, do not consider any reaction with the sludge, as it was assumed that the hard crust-like surface of the sludge would minimize reactions. Further, it is not clear how long the flushing phase will last or whether there will be short-term spikes in concentrations. Finally, it is assumed that pyrite weathering reactions will cease once the adit workings are flooded. There are, however, subaqueous conditions that exist where the weathering of pyrite and acid generation does not require oxygen. This pyrite weathering reaction series for this situation is as follows:

1) 2FeS2 + 7O2 + 2H2O 2Fe2 + 4SO4 + 4H+ Pyrite reacts with oxygen and water to produce ferrous iron, sulfate and acidity. 2) 4Fe2+ + O2 + 4H+ 4Fe3

+ + 2H2O Conversion of ferrous iron to ferric iron. 3) 4Fe3 + 12H2O 4Fe(OH)3 + 12H+ Hydrolysis of ferric iron with water produces ferric hydroxide (ferrihydrite) and additional acidity. This reaction is pH dependant in that with pH < 3.5 the ferric iron

of 85

stays in solution. Once pH > 3.5 a precipitate forms, referred to as “yellow boy”. 4) FeS2 + 14Fe3 + 8H2O 15Fe2 + +2So4 2- + 16H+ Oxidation of additional pyrite by ferric iron that was generated in reactions #1 and 2. This cyclic propagation of acid generation by iron takes place very rapidly and continues until the supply of ferric iron or pyrite is exhausted. Oxygen is not required for this reaction to occur.

The potential interaction between the iron hydroxide sludge and the overlying water chemistry is unclear. The sludge is likely a result of oxidization and leaching of sulphide minerals under oxidizing conditions and therefore stable under acidic, oxidizing conditions. If the submerged environment offers reducing conditions (possible due to anoxic conditions and the presence of a sulphide species), the sludge could become unstable, undergo a chemical reaction and either release its metal load or remain inert. The 0.75 m thick sludge’s surface area is approximately 25% of the total combined area of the floor, wall, and ceiling surfaces area. The interaction between it and the overlying water is critical to accurately predicting the adit discharge water chemistry. Increased ARD/ML would be considered significant and adverse.

Mitigation: • The company will submit a plan to deal with unexpected spikes in concentrations that occur in

the short term, and sustained concentrations above accepted values over the long term. One option would be short-term water treatment during this flushing phase, followed by decisions as part of the adaptive management plan to continue treatment to meet background water quality targets.

Rationale: As per comments submitted by Yukon Government and Environment Canada, expert opinion indicates something needs to be in place, on the ground, to manage any unforeseen events over both the short and long term periods. Water treatment is not something that can be quickly implemented as an adaptive response to changing conditions. Rather it is something that needs to be implemented from the outset. Having it in place prior to plugging of the adit in addition to a plan for unexpected events will ensure there is no potential for significant adverse effects.

3.3.2.3 Long Term Monitoring Phase It is expected that flooding of the underground workings will reduce oxidation of the exposed active surfaces and result in decreased long-term ARD and ML in the adit discharge water. Water quality of the discharge is expected to approach the background levels observed in other surface waters draining the rich pyrite shales of the Tom Sequence; however, the predicted water quality of the adit discharge is still expected to exceed CCME and EQS guidelines for many parameters, so that more site-specific standards were proposed (i.e., the 95th percentile of the background data set) for pH and 13 metals (aluminum, arsenic, cadmium, chromium, copper, iron, lead, nickel, selenium, silver, thallium, zinc and dissolved arsenic). Factors contributing to the elevated levels include:

• Acid rock drainage will still occur at reduced rates in sub-aqueous (anoxic) environments. • Water seepage will still flow over un-submerged walls and ceilings subject to elevated rates of

oxidation.

of 85

• Chemical and physical interactions between the sludge and overlying water are unclear and therefore predictions of discharge water chemistry are uncertain.

Increased ARD/ML would be considered significant and adverse.

Mitigation: • It is recommended that a basic water treatment system be installed to intercept the adit

discharge and ensure that water quality entering Sekie Creek #2 meets the background water quality targets.

Rationale: The level of uncertainty posed by this project makes it difficult to accurately predict what will happen once implemented. A water treatment system will bring certainty back into the equation. It will ensure that no matter what actually happens water discharged to the receiving environment willl be no worse than the background water quality targets.

• Fish tissue testing and analysis will be conducted where possible downstream of adit drainage

in the South Macmillan River to qualify current levels of metal bioaccumulation.

Rationale: To date little information has been collected in relation to bioaccumulation of metals in fish species that reside in this watershed. I am aware of the toxicity tests carried out by the proponent but this focuses on the direct effects of contaminated water. In contrast, tissue analysis will help to qualify the magnitude of effects currently experienced by fish species.

• During construction and flooding/flushing phase of this project the following monitoring will

be conducted: o Sample sites: W2, W3A, W6, T4, S2, T5, W8 and W5, if flowing; o Weekly monitoring of water quality prior to adit discharge to characterize baseline

conditions. Monitoring frequency will consider inclement weather conditions and site accessibility.

o Sediment and benthic invertebrate sampling to provide baseline data. Sampling to be done prior to adit discharge and during the first week post plug installation.

o Periodic observations of the integrity of the Lined Discharge Facility, Waste Rock Cover and other Water Management/Facilities.

• Over the long term (i.e. 3 years or termination of water licence) the following monitoring will

be conducted: o Sample sites: W2, W3A, W5, W6, T4, S2, T5 and W8); o Seasonal monitoring of water quality and sediment and benthic invertebrate sampling

to evaluate trends.

Rationale: The construction phase will cause substantial changes to how the adit functions and it will be important to measure potential changes. Data collected will provide valuable information for implementing adaptive management as required. This is true also for the longer 3 year period that this water licence covers.

of 85

3.2.4 Adaptive Management Plan

Adaptive management plans (AMP) are an effective way of identifying and responding to potentially significant adverse effects that may arise due to unpredictable changes in the environmental and/or socio-economic context of the project. An AMP is intended to complement specific mitigations such that both the predictable significant effects and those that are unpredictable are satisfactorily anticipated and mitigated. Project components that may be particularly sensitive to changes in the project context, and thus would require this approach, include:

• Sludge Management • Flooding and Flushing of Adit Workings • Effectiveness of Waste Rock Cover/Facility

Sludge Management Proposed sludge management essentially consists of the construction of the temporary berm on the upstream side of the adit to prevent sludge from entering the work zone and exiting the adit portal, and the construction of a 1200 m3 capacity lined containment pond. The containment facility is planned to be used only during the construction phase and has been sized to contain the sludge in the tunnel as well as the entire flow of water expected to be discharged through the tunnel during the construction of the berm. The pond may be undersized if the amount of sludge has been underestimated, the time required to complete all the construction activities has been underestimated, the settling rate of the sludge is overestimated, or the flow rate from the adit is underestimated. A combination of any or all of these conditions would result in pond overflow into to Sekie Creek #2 prior to settling of the sludge and contribute to creek contamination. Further, it has been assumed that the sludge will completely drain from the entrance of the adit during the construction stage; however, this may be a protracted process. Any disturbed and potentially mobile sludge remaining in the adit (downstream of the plug) could then potentially enter the creek after the construction phase. The increased loading would be considered significant and adverse. A plan must be put in place that monitors water and sludge levels in the pond, evaluates the effectiveness of sludge removal from the fist 100 m of the workings, monitors any buildup of sludge behind the berm, and utilizes a process for appropriate and timely responses to any issues. Flooding and Flushing of Adit Workings During the initial flooding and flushing stage, elevated concentrations of metals will accumulate in water dammed behind the adit plug. After an estimated 30 days, predicted concentrations in the adit discharge will exceed background conditions. The proponent’s model predicted that the worse effects (or highest concentrations of Zn for example) will only be ~11% higher than background. However, there are significant unknowns related to these predictions, notably:

• they are compared to a 2000-2008 data set rather than using lower concentration data from older data (which may be more representative of non-anthropogenic affected conditions);

• these predictions do not consider any reaction with the sludge during flooding or over the long-term;

• it is not clear how long the flushing phase will last or whether there will be short-term spikes in concentrations; and

• it is assumed that pyrite weathering reactions will cease once the adit workings are flooded.

of 85

A plan must be put in place that monitors the water discharge and water quality associated with the adit, and utilizes a process for appropriate and timely responses to any issues, including early development and deployment of a water treatment system. Effectiveness of Waste Rock Cover/Facility The waste rock cap will cover only 75% of the waste rock surface area, which may not be adequately effective to eliminate or, at the least, minimize the development of ARD/ML processes so that runoff or seepage from the facility does not lead to increased and unacceptable metal loadings into the receiving environment. A plan must be put in place that periodically monitors the water quality of runoff or seepage waters, and then utilizes a process for appropriate and timely responses to any issues. To effectively mitigate the potential significant adverse effects noted above related to unpredictable changes in the environment, an adaptive management plan that includes but is not limited to the following information must be developed by the proponent. It is to be submitted to an appropriate regulator for approval prior to proceeding with the proposed project. Note that for the purposes of this assessment, “appropriate regulator” in this context refers to YG – Mineral Resources Branch since they are the Decision Body for this project.

Mitigation: • Proponent shall prepare an Adaptive Management Plan and submit it to the Decision Body for

approval. The plan will incorporate the approach detailed in the proposal and as follows:

1. Establish trigger thresholds for the following based on the predictive modeling results and the anticipated response of the system to the installation of the plug:

a. Surface water quality in the receiving environment; b. Adit discharge water quality and quantity; c. Presence of seepage; d. Groundwater levels; and e. Temporary sludge containment pond and sludge. f. Waste rock cover and lined channel.

2. Routine review of results from the monitoring program and comparison to the

thresholds. 3. In the event that the monitoring data is above a trigger threshold, the following steps

will be carried out:

a. Determine likely cause trigger and assessment of the impacts to the receiving environment;

b. Develop an appropriate response plan to address problem; c. Seek regulatory approval for proposed actions in the event that a change to the

Water Licence and a review under YESAA is required; d. Implement the response plan as approved.

of 85

Rationale: This project has inherent uncertainties that are difficult to predict in advance of implementation. Some of these uncertainties pose potentially significant adverse affects to aquatic resources. Adaptive management plans (AMP) are an effective way of identifying and responding to unpredictable changes in the environmental and/or socio-economic context of the project. An AMP is intended to complement specific mitigations such that both the predictable significant effects and those that are unpredictable are satisfactorily mitigated.

4. Wildlife and Wildlife Habitat 4.1 Temporal and spatial overlap summary As noted in section 3.3 Biological Environment, the project overlaps a key wildlife area for mountain goats. It is in vicinity to key wildlife areas for various raptors and thinhorn sheep. Downstream wetlands are also key habitat for beaver and martin. Finally the project area is common habitat for grizzly and black bears. Project components that overlap with wildlife and wildlife habitat values include:

− camp operations 4.2 Effects characterization and significance determination Camp facilities and waste storage and disposal create odors which can become an attractant for bears increasing the likelihood of bear human conflict and ultimately the destruction of bears. It is the opinion of the assessor that the destruction of bears as a result of human error is a significant and adverse. Human presence can cause wild animals to become habituated to humans if the animals are rewarded with food or just become more comfortable around people. Once wild animals lose their fear of humans they can appear to become friendly and humans often become complacent potentially resulting in conflict. This could lead to injury or death to either the person or animal involved. The proponent has consulted the regional biologist in the area and proposed daily incineration of garbage as well as a gated and fenced camp compound and crew education. It is the opinion of the assessor that the proponent proposed mitigations will reduce the likelihood of potentially significant and adverse wildlife human conflict. An influx of people to an area that is regularly hunted by local people can cause a level of discomfort for those that traditionally hunt the area. There is the potential for employees who are staying and working in the area to have a better chance of having a successful hunt. There is a potential concern with over-hunting in the area and potentially a reduced success rate for local people. It should be acknowledged that the proponent has committed to a no hunting policy for employees. This reduces the potential for significant adverse effects on wildlife populations due to over-harvesting. However, in the absence of this sort of policy effects could be significant and adverse. Project activities may also induce stress reactions with mountain goats, reducing their ability to survive. Failure to monitor wildlife in the area and reduce the potential for negative interactions could lead to significant adverse effects. This is true also for any raptors that may be present in the area. I will acknowledge that the likelihood of nests in trees near the adit is very low since it is mostly above

of 85

treeline. Effects to raptors would more likely occur close to camp in the main South Macmillan valley. I don’t see any implications for Thinhorn sheep since their winter range is on the west side of the Macmillan River and I’m not aware of distinct summer ranges that the project could affect.

Mitigation:

• Proponent shall keep all garbage, including kitchen waste, in a container that prevents access by bears and other wildlife, until properly disposed of in accordance with the Solid Waste Regulation.

• When burning kitchen waste on site, it must be burned regularly to reduce odors that might

attract wildlife and be burned to ash by forced air or fuel fired incineration.

• The camp compound will be fenced and gated.

• If wildlife becomes a nuisance or problem the proponent shall install a portable electric fence around the perimeter of the camp.

• All nuisances or problems with wildlife shall be reported to the local conservation officer

immediately for assistance in effective means of reducing wildlife mortality.

Rationale: These measures will prevent animals from becoming attracted to the camp and also prevent access to the camp. Keeping local conservation staff engaged will help reduce injury and death to wildlife as a result of interactions and incidents.

• Proponent shall enforce a no-hunting policy.

• Proponent shall avoid wildlife whenever possible.

• Proponent shall encourage employees to fill out a wildlife log to document wildlife

occurrences at all project locations.

Rationale: These measures will reduce the impact employees could potentially have on local wildlife populations. Documenting wildlife observations will further help proper management efforts.

5. Health and Safety 5.1 Temporal and spatial overlap summary By their nature, temporary camps pose potential health and safety risks with regards to proper sanitation, waste, food storage, handling and preparation and potable water. Further, this project is in a remote location and presents some challenging site conditions. The topography makes the adit area prone to debris slides, rockfall and avalanches. The adit itself is over 30 years old and has officially been ‘closed’ since 1993. Conditions inside are likely not stable. The project location means it is

of 85

isolated from normal medical and support services that would help to alleviate some of these risks. In consideration of these facts, project components that overlap with health and safety values include:

− camp operations − underground work

5.2 Effects characterization and significance determination Camp Operations – General Sanitation Operation of the camp may lead to conditions of overcrowding and potentially unsanitary conditions. This in turn may result in the spread of disease amoung the camp population. The likelihood of this occurring is low considering the low number of people and temporary usage. However the consequences could have a considerable impact on the health of people residing in camp. I have considered the requirements of the Camp Sanitation Regulations as per the Public Health and Safety Act, and specifically sections 4, and 10-18. Given this consideration I’m satisfied that compliance with this legislation will adequately eliminate, reduce or control the potential effects noted above so that they are not significant and adverse. Camp Operations – Waste Improper management of garbage and other waste produced by the camp and/or failure of a waste management system has the potential to contaminate water sources and lead to unsanitary conditions. Given the size of this camp there is potential for a moderate volume of waste to be generated. Effects are considered to be significant and adverse.

Mitigation: • Proponent shall ensure that all solid waste from project activities is transported to and

deposited at an approved solid waste disposal facility.

Rationale: Given the moderate size of this camp, remote location and potential volume of garbage it is imperative that waste is managed appropriately and expeditiously.

Camp Operations – Sewage Management The project proposes use of a port-a-potty and a greywater pit. Human waste produced from camps is known to be a vector for a number of pathogens (ex. E. Coli bacteria) and parasites (ex. Giardia Spp.). Improper management of human waste or failure of the proposed waste management system may lead to transmission of pathogens and parasites. Transmission may occur through the ingestion of untreated/unfiltered water affected by contaminated sources. Effects can range from minor gastrointestinal problems associated with some parasites, to kidney failure to death as known to occur with some strains of bacteria. Parasites like Giardia, which causes “beaver fever”, move throughout the environment using humans, pet, and wild animals, and specifically their waste, as the distribution system. Human illness as a result of improper human waste facilities and water source would be considered an adverse effect of this project.

of 85

I have considered the requirements of the Sewage Disposal Systems Regulation and the Pubic Health and Safety Act and notes that the sewage disposal system proposed must comply with this non-discretionary legislation. The regulations speak to acceptable practices and specifically: location, acceptable types, construction and operation; maintenance; and abandonment and site reclamation associated with sewage disposal systems. I am satisfied that compliance with this legislation will adequately eliminate, reduce or control the potentially significant effects related to the disposal of waste on health and safety. Camp Operations – Food Storage, Handling and Preparation Operation of the camp will require storage, preparation and serving of food. Improper facilities for the storage of food may lead to disease within the camp population through foodborne illnesses. Improper handling, preparation and serving of food by staff may also lead to unsanitary conditions and the potential spread of disease. Given the potential consequences the effects are considered significant and adverse. I have considered the requirements of the Camp Sanitation Regulations as per the Public Health and Safety Act, and specifically sections 4, and 10-18. Given this consideration I am satisfied that compliance with this legislation will adequately eliminate, reduce or control the majority of potential effects noted above so that they are not significant and adverse. However in my opinion this legislation does not speak adequately to ensuring proper training is in place to further mitigate these effects.

Mitigation: • Staff preparing meals for others shall be trained in proper food handling techniques so as to

prevent food borne illnesses among camp population. Rationale: Camps of this size (i.e. 10 people) have an increased risk for unsanitary food preparation and handling. Proper training is a reasonable measure to address this issue from the outset.

Camp Operations – Direct Use of Water The proposal indicates drinking water will be bottled. All other water will be sourced from the South Macmillan River or its tributaries. I am not sure if bottled water will be used not only for drinking but for other uses such as preparing food (making juice, washing produce, etc.), washing dishes, and brushing teeth. Water provided for these uses may be contaminated depending on the source and how it is handled and managed. The effects of ingesting untreated/unfiltered water from contaminated sources can range from minor gastrointestinal problems associated with some parasites, to kidney failure to death as known to occur with some strains of bacteria. Parasites like Giardia, which causes “beaver fever”, move throughout the environment using humans, pets, and wild mammals, and specifically their waste, as the distribution system. Equally important would be the potential for metal contamination and low pH levels associated with some of the streams in this region. Given the potential volume of potable water required to support this project and the consequences of using contaminated water, the effects are considered significant and adverse. I will note that while there is a general requirement through current legislation for providing potable water and not causing a ‘public nuisance’, specific mitigations to alleviate the effects mentioned are currently in the form of guidelines.

of 85

Mitigation: • The health related parameters of the Guidelines for Canadian Drinking Water Quality must

be met for all water used for drinking, and general camp use.

Rationale: This is the national standard for drinking water and adherence to it will ensure no significant adverse effects are experienced.

Underground and Aboveground Work – Planning for Safety In the following sections I make reference to non-discretionary legislation. What I’m referring to are provisions within legislation that are required to be done through law. There is very little flexibility in these matters – much like traffic speed limits, as a proponent you are either in compliance or not. These provisions are standing items that constantly apply and this makes them very useful in an assessment. In many cases they fully mitigate significant adverse effects and there is no need for additional mitigation. Since they are standing items it is our practice to reference them but not to make them a formal recommendation. However, with issues of health and safety there is an opportunity to improve upon these required provisions. The case in point is the Occupational Health and Safety Act and corresponding regulations. This legislation has an important role in protecting worker health and safety and supporting these workers when they experience accidents in the workplace. The legislation contains numerous non-discretionary provisions that are required to be fully addressed as soon as a worker begins their work on behalf of an employer. What seems to be missing though is some qualification of how to adequately address some of these requirements. For example, health and safety plans are required but there is very little direction in the provisions on what an adequate plan should cover. One of the main support resources available to proponents in this matter is also the authority for this legislation, the Yukon Workers’ Compensation Health & Safety Board. Representatives of this organization are in a position to qualify exactly what is required of a proponent to implement their project in a safe manner. The health and safety requirements can be quite dynamic and complex depending on the project. With this particular project I am concerned first with the remoteness of the site and the distance to proper medical services. Second, with the safety risks of working in a steep area prone to debris slides, rockfall runouts and avalanches. Third, the risks of working within an old adit in an area prone to earthquakes. The implications of not adequately addressing these risks and legislative requirements may lead to significant adverse effects. In consideration of this I believe the following mitigation is important to include in this recommendation.

Mitigation: • Proponent shall meet with representatives of the Yukon Workers’ Compensation Health &

Safety Board to discuss their project at least 30 days prior to commencement. The purpose of these discussions will be to ensure satisfactory compliance with relevant provisions of the Occupational Health and Safety Act and associated regulations. At a minimum the following topics shall be discussed:

− Health and safety risks associated with this project and relevant health and safety plans

to mitigate these risks; − Injury reporting and return to work plan;

of 85

− Mine plans, drawings and engineering reports; and − Policy and procedure specific to aboveground and underground operations.

Rationale: Representatives of this Board are in the best position to help the proponent navigate through their legal health and safety requirements. From my perspective some of the important risks that need to be discussed, at a minimum, include:

− remote project location and medical support services; − geohazards (i.e. rockfall, debris flow and avalanches); and − underground work within the adit (e.g. potential adit collapse, creating a safe work

area, ventilation, emergency equipment and mine rescue procedures). Under this legislation proponents are required to contact this board 30 days prior to commencing work. However given the complexities of this project it is in the best interests of the proponent to contact them as soon as feasible.

Underground Work – Air Quality Implications for Worker Safety The proposal indicates that oxygen levels within the adit, including some of the deepest areas, is nearly equal to what would be found in the open. However working underground may put workers into confined spaces that are quite remote from natural sources of oxygen such that they are completely reliant on ventilation equipment. This would certainly be the case in the event of any accidents or malfunctions. Further, activities such as blasting, drilling and operation of machinery may lead to the accumulation of particulate matter (i.e. rock dust; diesel exhaust) and reduced air quality adversely affecting human health. Particulate matter may constitute inhalable and fine particles smaller than 10 micrometers in diameter that may generally pass through the throat and nose and enter the lungs (United States Environmental Protection Agency). According to the United States Mine Rescue Association, effects include:

• increased respiratory symptoms (i.e. irritation of airways, coughing or difficulty breathing); • decreased lung function; • development of lung and heart ailments (i.e. chronic bronchitis; lung cancer); and • over time premature death in people who develop lung or heart disease from long term or

intense exposure to particulates. Given the likelihood of workers being exposed to particulate matter and the potential severity of effects, they are considered significant and adverse. In addition to the effects of particulate matter, if ventilation equipment was to fail through improper operation, malfunction or accident workers could potentially be working in an oxygen deficient environment or stranded without oxygen and have limited options for finding an alternative source. A reduction or absence of oxygen could lead to hypoxia oxygen deficiency, a shortage of oxygen in the body. This in turn may cause discomfort, reduced body function, unconsciousness and ultimately brain death if not recognized and resolved immediately. While the likelihood of this effect occurring requires some improper operation, malfunction or accident, if it were to occur it would be considered significant and adverse. Air quality could also be compromised by gases that may accumulate over time in some of the deeper recesses of the workings where air is not sufficiently recycled and could become stagnant. Carbon

of 85

monoxide, which results from the incomplete combustion of organic carbon-based materials, may be emitted from generators, pumps and vehicles. Nitrogen dioxide is an extremely toxic gas to the human body and is produced from the detonation of explosives as is sulfur dioxide when blasting sulfide ores. Carbon dioxide (e.g. associated with rotting mine timbers), hydrogen (e.g. incomplete combustion in explosives), hydrogen sulfide (e.g. decomposition of sulfur compounds), methane (e.g. associated with coal seams) and nitrogen are also common gases that are of concern in underground workings, though less so in relation to this project (United States Environmental Protection Agency). Effects of these gases to humans range from headaches, tiredness, irritation to nose and throat, dizziness and nausea to convulsions and ultimately unconsciousness or in some cases pulmonary oedema. If a situation resulting in such effects is not quickly identified and resolved it could lead to injury or death of workers. While the effects of these gases require a number of variables to interact for them to become likely, if they were to occur they would be considered significant and adverse. I have reviewed the requirements of non-discretionary legislation and specifically the Occupational Health and Safety Regulations and the Occupational Health and Safety Act. The following address the noted effects:

• Part 2 – Confined Spaces; • Part 8 – Materials and Storage (i.e. rock dust); • Part 14 – Blasting; • Part 15 – Surface and Underground Mines or Projects (i.e. mine rescue); and • Part 16 – Mine Shafts and Hoists (i.e. ventilation and heating; safety examinations and

certificates). For example, the regulations specify exposure limits for workers to dust that are not to be exceeded and what is to be done if there is a system failure in the ventilation system. I am satisfied that compliance with this legislation will adequately eliminate, reduce or control potential significant effects related to underground quartz exploration and air quality implications for health and safety. Underground Work – Implications of Adit Failure on Worker Safety The practice of working underground, in this case to install an adit plug and pressure relief valve, has inherent safety risks associated with it. Underground operations place workers initially into a foreign and controlled environment. Over time this environment may become more familiar but it will still need to be strictly controlled to make it safe and comfortable to work within (i.e. ventilation, heat, lights, efficient access and exit). Part of this control is in relation to securing the excavation so that there is no risk of failure or collapse of the structure internally or blockage of the portal itself (i.e. with respect to the steep slopes, permafrost and avalanche potential). A failure event is one of the major risks to workers when working underground and effects could be serious. They include:

• indirectly isolating workers from possible escape routes and supplies necessary for survival until a rescue can be implemented;

• production of particulate matter and related air quality effects over the short term; • directly injuring workers with potential for long term disability; and • death.

Since underground work requires a controlled environment to safely work within, it is particularly

of 85

sensitive to unpredictable changes (i.e. earthquakes; avalanches blocking the adit). It also can not afford improper practices, malfunctions or accidents. Given the remote nature of this site, the frequency of earthquake epicenters in close proximity, the extent of faultlines and the steep topography, these effects are considered to be significant and adverse. I have considered the requirements of non-discretionary legislation and specifically again the Occupational Health and Safety Regulations and the Occupational Health and Safety Act. The following address the noted effects:

• Part 2 – Confined Spaces; • Part 6 – Mobile Equipment; • Part 8 – Materials and Storage (i.e. unconsolidated and solid material, hazardous substances,

battery charging, compressed gas containers, rock dust, rock crushing); • Part 10 – Construction and Building Safety; • Part 14 – Blasting (i.e. transportation and storage of explosives aboveground and underground,

blending, drilling, handling, loading holes, guarding, misfires, underwater blasting and avalanche control);

• Part 15 – Surface and Underground Mines or Projects (i.e. mine closure, fire protection, mine rescue, electrical, underground haulage); and

• Part 16 – Mine Shafts and Hoists (i.e. raising, stoping, ventilation and heating, shaft-sinking, rope attachments, skips and cages, electric hoists, safety examinations and certificates, hoist operators and communication).

I am satisfied that compliance with this legislation will adequately eliminate, reduce or control the potential significant effects of adit failure associated with working underground on health and safety. Underground Work – Use of Explosives The proposal states that approximately 680kg will be used to support work within the adit. Transporting, storing, handling and detonating explosives poses inherent safety risks to workers. Effects associated with poor operating practices, accidents or malfunctions may be quite serious and include injury and death. These effects are considered to be significant and adverse. I have considered the requirements of the following non-discretionary legislation:

• Explosives Act and Explosives Regulations; • Transportation of Dangerous Goods Act; • Quartz Mining Land Use Regulations (Schedule 1, Part M); • Occupational Health and Safety Act and Occupational Health and Safety Regulations.

o Part 14 – Blasting (i.e. transportation and storage of explosives aboveground and underground, blending, drilling, handling, loading holes, guarding, misfires, underwater blasting and avalanche control)

I am satisfied that compliance with this legislation will adequately eliminate, reduce or control the potentially significant effects related to the use of explosives on health and safety.

of 85

6. Effects of the Environment on the Project 6.1 Temporal and spatial overlap summary Project components that overlap with potential effects of the environment include:

− underground work − aboveground work

6.2 Effects characterization and significance determination Underground Work The key aspects of the environment that may cause effects to underground work and its eventual outcome are earthquakes and geohazards. Both aspects are influenced by dynamics in local terrain and climate conditions. As noted, earthquakes are relatively frequent in proximity to the project area. An earthquake event during this project could catalyze debris flows and rockfall runouts. Debris and rockfall could also catalyze for other reasons. For example, some of the steep slopes in vicinity of the adit exceed the dry friction angle. High precipitation events or melting events could precipitate movement of debris and rockfall. The section on health and safety (section 5 above) addresses how these effects could be mitigated to protect workers. However there are also implications for the longterm success of the adit plug. Once installed, the project design relies on continued adit discharge as opposed to completely stopping flow. Debris flow and rockfall could jeopardize this design and potentially block or reduce adit discharge. This in turn could place added pressure back into the flooded workings. An earthquake could also compromise or disrupt the plug, reducing its effectiveness. Despite the potential magnitude of some of these effects I’m satisfied that the proposed routine monitoring of the project area will ensure a quick response to any such event. Also, the remoteness and short window for accessing the area ensures limited public access and minimizes related safety issues. The plug design proposes a sheer strength of 500 kPa which is comparable to plugs implemented in other regions. I am not aware of how this design would hold up to a serious earthquake event but again, any potential effects could be adaptively managed with minimal risk. At this point I don’t believe the project needs to account for these specific unknowns. Aboveground Work Earthquakes, debris flows and rockfall runouts, whether in concert or individually, could also pose effects to work being done aboveground. This could be during the project and also after features like the waste rock liner and lined discharge channel are established. Again, I’ve addressed health and safety implications in section 5 above. There is still a risk posed to the actual project features established as a result of this project. For example, rockfall runouts could damage the lined discharge channel. Again it’s my impression that the routine monitoring proposed will help these situations to be managed adaptively. And in this case the barrier layers incorporated into the design of these features will go a long way to ensuring they are unaffected by such events.

of 85

7. Cumulative Effects Assessment As per section 42 of YESAA, an assessment of cumulative effects shall consider the interaction of residual effects of the proposed project with the residual effects of:

• projects for which proposals have been submitted for assessment under YESAA; and • existing, or proposed activities that are known to the Designated Office.

The combined interactions of residual effects for these activities may produce significant adverse cumulative effects. From my perspective, water and aquatic resources are the primary values that could experience cumulative effects as a result of this project interacting with others. As such, cumulative effects to these two values will be considered. This section will provide:

• an overview of the temporal/spatial overlap between the proposed project and other activities; and

• a characterization of the potential residual effects and their significance. 7.1 Temporal and Spatial Overlap The temporal scope for considering proposals submitted and other existing or proposed activities is the duration of this project as proposed. The spatial scope encompasses the South Macmillan watershed. 7.1.1 Proposals Submitted I am aware of the following projects that have been submitted within the South Macmillan watershed:

• 2008-0079 – Sekie Creek Bridge Replacement (Transportation) • 2008-0078 – Macmillan River #2 Bridge Replacement (Transportation) • 2008-0032 – Andrew Base Metal Project Revision (Quartz Exploration) • 2007-0192 – Andrew Property Winter Trail (Quartz Exploration) • 2007-0027 – Macmillan River Bridge #3 Replacement (Transportation) • 2007-0023 – Jeff Creek Bridge Replacement (Transportation)

I’ve listed projects related to the Andrew property since they fit the criteria of being within the South Macmillan watershed. It is important to note however that this property is located approximately 176 km downstream of the Tom adit. It’s my opinion that there would be very little interaction between these projects and as such I will not be considering it further. Similarly, I have not included one of the other prominent projects in this region, quartz exploration at Mactung. The reason is that project effects to water quality and thus aquatic resources would report to the Hess River and ultimately the Steward watershed. This would not present any overlap with this project given the parameters of this cumulative effects assessment.

of 85

7.1.2 Existing or Proposed Activities I am aware of the following activities:

• North Canol Highway • Past quartz exploration activities on the Jason Property.

7.2 Residual Effect Characterization and Determination of Significance The projects and activities I’ve identified can generally be divided into two sectors: quartz exploration and transportation. The main quartz exploration activities have occurred historically on the Jason property which is directly to the west of the Tom Property. This presents the most compelling potential for cumulative effects given its proximity. Transportation activities include the continued use and maintenance of the North Canol Highway. Most of the recent projects have been bridge replacements. Quartz Exploration Exploration of the Jason property was initiated in 1974 and resulted in exploration roads, extensive diamond and rotary drilling and trenching. The property was purchased by the proponent in 2007 but there has been no activity to date. Environment Canada raised concerns about potential cumulative effects that may be influenced by drill holes on the Jason property:

“Our information on water quality indicates that through-out the early 1980's and onwards the South Macmillan river quality has been gradually degraded. We would like to point out the cumulative effects of adjacent Hudson Bay Mining property (Jason claims) on the west side of the Macmillan River (see attached map). One of the Jason property flowing drill hole discharge was 1.21 mg/l T. Zn on July 9, 1981 while values of the three flowing bore holes ranges from 1.14 to 12.1 mg/ T.Zn September 28, 2006.”

Based on this information, the direct residual effects of the Jason property are the contribution of metal loading and acid rock drainage to the South Macmillan watershed. Indirect residual effects include impairment and removal of fish habitat and acute and chronic, sub-lethal and lethal effects to benthic invertebrates and fish. As noted, background levels of metals are high in this drainage and watercourses in both quartz properties. It is important to acknowledge that natural mineralization and acidity contributes greatly to current conditions. It is problematic when human induced activities, especially those that are easily remediated (e.g. plugging old drillholes to prevent flow), are having negative influences over and above poor natural conditions. However, in my opinion I don’t believe there is a strong enough additive interaction between these two projects and the poor water quality conditions downstream. As long as mitigations recommended in this report are accepted and implemented, the deposit of waste water associated with this project should have reduced interaction with the residual effects of the Jason property. Having concluded this, I still feel compelled to make a suggestion. As the current owner of the Jason property I believe the proponent has an opportunity to improve conditions. This effort would dovetail with the efforts being made on the Tom property.

of 85

Suggestion: • Remediate all drill and bore holes on the Jason property that are contributing to adverse

effects to water quality. Transportation Continued use and maintenance of the North Canol highway, including the recent bridge replacements, has the potential to contribute sediment loading to the South Macmillan watercourses. Sedimentation has the direction residual effect of increasing turbidity and potentially making water resources unsuitable for aquatic organisms. Indirect residual effects to fish habitat include:

• alteration of water chemistry (e.g. increased turbidity can increase temperature and reduce oxygen content);

• alteration of productivity (e.g. changes to types and numbers of invertebrate life, a food source for many kinds of fish);

• abrasion or clogging of fish gills which may cause fish to suffocate; • stress and nervous system damage to fish, which may affect their ability to forage

successfully, cause reproduction problems and increased offspring mortality, and death; • effects to fish reproduction by:

o alteration of oxygen levels which are important to viability of eggs and young fish; and

o creation of a physical barrier (ex. silt layer) that removes spawning or rearing habitat (gravels containing incubating eggs can become covered with sediment which can result in the eggs being smothered).

The interaction of these residual effects with those associated with this project (i.e. metal loading and acidity) ultimately may reduce or remove aquatic habitat and lead to acute and chronic, sub-lethal and lethal effects to benthic invertebrates and fish. However it is important to note that each of the transportation projects was required to have an assessment and consequently implement mitigations to reduce these effects. Further, while residual effects of this project are longterm, the residual effects of sedimentation are short-term in duration. With the required mitigations in place these residual effects should also not be significant to the greater South Macmillan watershed. In my opinion the potential cumulative effects are not significant and adverse.

of 85

10) Designated Office Recommendation

The Watson Lake Designated Office, in concluding its evaluation of Project #2008-0242, pursuant to Section 56(1) of the Yukon Environmental and Socio-economic Assessment Act:

S56 (1)(a)

recommends to the decision body(ies) that the project be allowed to proceed, as the Designated Office has determined that the project will not have significant adverse environmental or socio-economic effects in or outside Yukon;

S56 (1)(b)

recommends to the decision body(ies) that the project be allowed to proceed, subject to specified terms and conditions, as the Designated Office has determined that the project will have significant adverse environmental or socio-economic effects in or outside Yukon that can be mitigated by those terms and conditions;

S56 (1)(c)

recommends to the decision body(ies) that the project not be allowed to proceed, as the Designated Office has determined that the project will have significant adverse environmental or socio-economic effects in or outside Yukon that cannot be mitigated; or

S56 (1)(d)

refers the project to the Executive Committee for a screening, as the Designated Office cannot determine whether the project will have significant adverse environmental or socio-economic effects after taking into account any mitigative measures included in the project proposal.

of 85

56(1)(b) Recommended Terms and Conditions for the Project The following mitigative measures shall be complied with: Water Resources 1. Complete adit construction early enough in year to allow for monitoring to begin

during ice-free season, and to accommodate slow or rapid filling periods.

Rationale: This will allow more lead time to monitor conditions and implement adaptive management as needed. Once freeze-up and low-flow conditions occur in late fall the opportunity to monitor and thus understand conditions on-the-ground is very limited. The adaptive management relies on field information to be effective.

2. Monitoring of head behind the adit plug is planned; continuous recording of head is

recommended to facilitate estimation of volumes and ascertain whether bedrock fractures are collecting a large proportion of the adit inflow.

3. Seepage flow rates should be measured whenever and as often as logistically feasible

to establish a baseline against which future flow rates (after flooding has been completed) can be compared. This would enable one to develop reasonably accurate estimates of the seep flow rates as a baseline to help evaluate whether the proposed project will affect them.

Rationale: This type of information is critical for the Adaptive Management Plan.

4. Remediate all drill and bore holes on the Tom property that have flow. Remediation

should be designed to stop this flow (e.g. appropriate plug techniques). Emphasis should be on those holes that are below the predicted flood elevation for the adit workings.

Rationale: Plugging and otherwise remediating known drill and bore holes will reduce the potential adit discharge to occur from uncontrolled point sources.

Aquatic Resources 5. All water withdrawals from stream reaches designated as fish streams must be

screened to prevent the entrainment and/or entrapment of fish.

Rationale: This is a standard measure that effectively deals with this effect. It is intended to complement the more specific recommendation made by the Department of Fisheries and Oceans.

6. A contingency plan will be developed to handle any volumes of sludge and water

above design capacity, including the capability to easily increase facility dimensions.

Rationale: This will reduce the potential for the pond to overflow prior to sludge settling.

of 85

7. Due to the uncertainties in discharge water quality, a basic water treatment system should be developed and be ready to install to intercept the adit discharge and ensure that water quality entering Sekie #2 meets the background water quality targets.

8. A shake test, similar to that carried out on the adit rock wall samples, will be

conducted with representative sludge samples to determine the effect on adit drainage water chemistry and ultimately on the three effect pathways in the adjacent watercourses.

9. Periodic observations and sampling of seeps (if present) at the base of the waste rock

pile. 10. Adaptive Management Plan will include a plan for addressing the presence of seeps

and water affected by ARD/ML. 11. The surrounding terrain will be graded to redirected flow into the lined discharge

channel. 12. Monitor the conditions and size of the waste rock cover. Develop a plan to maintain

and repair the cover in relation to long-term degradation or short-term exceptional events (i.e., flooding, debris flows, avalanches).

13. Adaptive Management Plan will include provisions to increase cap area and minimize

or eliminate runoff into the pile slopes. 14. Work that will disturb soils will be stopped during periods of high precipitation. 15. Appropriate erosion and sediment control BMP will be developed and followed. 16. Adaptive Management Plan will include periodic observations and monitoring of

appropriate parameters, followed by continued assessment to address any unforeseen or low probability events (i.e. hillslope failures, avalanches, debris flows).

17. The company will submit a plan to deal with unexpected spikes in metal

concentrations that occur in the short term, and sustained concentrations above accepted values over the long term. One option would be short-term water treatment during this flushing phase, followed by decisions as part of the adaptive management plan to continue treatment to meet background water quality targets.

Rationale: As per comments submitted by Yukon Government and Environment Canada, expert opinion indicates something needs to be in place, on the ground, to manage any unforeseen events over both the short and long term periods. Water treatment is not something that can be quickly implemented as an adaptive response to changing conditions. Rather it is something that needs to be implemented from the outset. Having it in place prior to plugging of the adit in addition to a plan for unexpected events will

of 85

ensure there is no potential for significant adverse effects. 18. It is recommended that a basic water treatment system be installed to intercept the

adit discharge and ensure that water quality entering Sekie Creek #2 meets the background water quality targets.

Rationale: The level of uncertainty posed by this project makes it difficult to accurately predict what will happen once implemented. A water treatment system will bring certainty back into the equation. It will ensure that no matter what actually happens water discharged to the receiving environment willl be no worse than the background water quality targets.

19. Fish tissue testing and analysis will be conducted where possible downstream of adit

drainage in the South Macmillan River to qualify current levels of metal bioaccumulation.

Rationale: To date little information has been collected in relation to bioaccumulation of metals in fish species that reside in this watershed. I am aware of the toxicity tests carried out by the proponent but this focuses on the direct effects of contaminated water. In contrast, tissue analysis will help to qualify the magnitude of effects currently experienced by fish species.

20. During construction and flooding/flushing phase of this project the following

monitoring will be conducted: • Sample sites: W2, W3A, W6, T4, S2, T5, W8 and W5, if flowing; • Weekly monitoring of water quality prior to adit discharge to characterize

baseline conditions. Monitoring frequency will consider inclement weather conditions and site accessibility.

• Sediment and benthic invertebrate sampling to provide baseline data. Sampling to be done prior to adit discharge and during the first week post plug installation.

• Periodic observations of the integrity of the Lined Discharge Facility, Waste Rock Cover and other Water Management/Facilities.

21. Over the long term (i.e. 3 years or termination of water licence) the following

monitoring will be conducted: • Sample sites: W2, W3A, W5, W6, T4, S2, T5 and W8); • Seasonal monitoring of water quality and sediment and benthic invertebrate

sampling to evaluate trends.

Rationale: The construction phase will cause substantial changes to how the adit functions and it will be important to measure potential changes. Data collected will provide valuable information for implementing adaptive management as required. This is true also for the longer 3 year period that this water licence covers.

of 85

22. Proponent shall prepare an Adaptive Management Plan and submit it to the Decision Body for approval. The plan will incorporate the approach detailed in the proposal and as follows:

1. Establish trigger thresholds for the following based on the predictive modeling

results and the anticipated response of the system to the installation of the plug: a. Surface water quality in the receiving environment; b. Adit discharge water quality and quantity; c. Presence of seepage; d. Groundwater levels; and e. Temporary sludge containment pond and sludge. f. Waste rock cover and lined channel.

2. Routine review of results from the monitoring program and comparison to the

thresholds.

3. In the event that the monitoring data is above a trigger threshold, the following steps will be carried out:

a. Determine likely cause trigger and assessment of the impacts to the receiving environment;

b. Develop an appropriate response plan to address problem; c. Seek regulatory approval for proposed actions in the event that a change to

the Water Licence and a review under YESAA is required; d. Implement the response plan as approved.

Rationale: This project has inherent uncertainties that are difficult to predict in advance of implementation. Some of these uncertainties pose potentially significant adverse affects to aquatic resources. Adaptive management plans (AMP) are an effective way of identifying and responding to unpredictable changes in the environmental and/or socio-economic context of the project. An AMP is intended to complement specific mitigations such that both the predictable significant effects and those that are unpredictable are satisfactorily mitigated.

Wildlife and Wildlife Habitat 23. Proponent shall keep all garbage, including kitchen waste, in a container that prevents

access by bears and other wildlife, until properly disposed of in accordance with the Solid Waste Regulation.

24. When burning kitchen waste on site, it must be burned regularly to reduce odors that

might attract wildlife and be burned to ash by forced air or fuel fired incineration. 25. The camp compound will be fenced and gated. 26. If wildlife becomes a nuisance or problem the proponent shall install a portable

of 85

electric fence around the perimeter of the camp. 27. All nuisances or problems with wildlife shall be reported to the local conservation

officer immediately for assistance in effective means of reducing wildlife mortality.

Rationale: These measures will prevent animals from becoming attracted to the camp and also prevent access to the camp. Keeping local conservation staff engaged will help reduce injury and death to wildlife as a result of interactions and incidents.

28. Proponent shall enforce a no-hunting policy. 29. Proponent shall avoid wildlife whenever possible. 30. Proponent shall encourage employees to fill out a wildlife log to document wildlife

occurrences at all project locations.

Rationale: These measures will reduce the impact employees could potentially have on local wildlife populations. Documenting wildlife observations will further help proper management efforts.

Health and Safety 31. Proponent shall ensure that all solid waste from project activities is transported to and

deposited at an approved solid waste disposal facility. Rationale: Given the moderate size of this camp, remote location and potential volume of garbage it is imperative that waste is managed appropriately and expeditiously.

32. Staff preparing meals for others shall be trained in proper food handling techniques so

as to prevent food borne illnesses among camp population. Rationale: Camps of this size (i.e. 10 people) have an increased risk for unsanitary food preparation and handling. Proper training is a reasonable measure to address this issue from the outset.

33. The health related parameters of the Guidelines for Canadian Drinking Water Quality

must be met for all water used for drinking, and general camp use. Rationale: This is the national standard for drinking water and adherence to it will ensure no significant adverse effects are experienced.

34. Proponent shall meet with representatives of the Yukon Workers’ Compensation

Health & Safety Board to discuss their project at least 30 days prior to commencement. The purpose of these discussions will be to ensure satisfactory compliance with relevant provisions of the Occupational Health and Safety Act and associated regulations. At a minimum the following topics shall be discussed:

− Health and safety risks associated with this project and relevant health and safety

plans to mitigate these risks;

of 85

− Injury reporting and return to work plan; − Mine plans, drawings and engineering reports; and − Policy and procedure specific to aboveground and underground operations.

Rationale: Representatives of this Board are in the best position to help the proponent navigate through their legal health and safety requirements. From my perspective some of the important risks that need to be discussed, at a minimum, include:

− remote project location and medical support services; − geohazards (i.e. rockfall, debris flow and avalanches); and − underground work within the adit (e.g. potential adit collapse, creating

a safe work area, ventilation, emergency equipment and mine rescue procedures).

Under this legislation proponents are required to contact this board 30 days prior to commencing work. However given the complexities of this project it is in the best interests of the proponent to contact them as soon as feasible.

Suggestions for the Project The following measures are provided for the proponent and Decision Body to consider: 1. Blasting to be completed in dewatered area. 2. Remediate all drill and bore holes on the Jason property that are contributing to

adverse effects to water quality. 3. Proponent shall monitor the remaining exposed portion of the adit post installation of

the plug. Sampling will determine the rates of metal release, concentrations and potential loading contributions to adit discharge.

Rationale: Once the plug is installed it will be important to distinguish where exactly metal and acid contributions are coming from. One of the ways to monitor is through the “Minewall technique” developed for the former Canadian Mine Environment Neutral Drainage (MEND) Program. As per documentation available “Minewall uses a general mass-balance approach for all inputs and outputs of water and chemistry, plus the water level and chemistry of any accumulating mine water. It is a flexible tool for forecasting geochemical conditions in open-pit mines or underground workings” (Morth et al. 1972). It relies on 4 steps:

1. Obtain unit-area reaction rates from Minewall stations. 2. Compile lateral, inclined and vertical exposed surface areas by elevation

in underground workings based on site-specific survey data. 3. Estimate fracture intensity or design the blast intensity in order to obtain

the ratio of reactive surface area to exposed surface area, and include other rock surface like waste rock.

of 85

11) Certification Assessment Report Prepared By Signature Steve Caram Steve Wilbur

Date December 19, 2008

Authorized By Signature Steve Caram

Date December 19, 2008

12) Acknowledgements I believe it is important to acknowledge first, the efforts of the proponent and its representatives. The project proposal and subsequent information provided was very comprehensive, thoughtfully written and well organized. I appreciated the patience displayed by the proponent as we worked through the issues and complexities of this project. The time taken to finish this assessment should not be seen as any lacking in the efforts of the proponent, but rather as a reflection of the challenges this project presented. Second, I wish to acknowledge our consultant Steve Wilbur and his team at Jacques Whitford for their contribution to this report. The sheer volume of proposal information required an impressive response from him and his team in order to successfully complete this report.

4. Estimate loadings that will be released on a regular or periodic basis, or retained if/until that portion of the wall is submerged.

It is important to note that the extent of this issue is not isolated to the rock face of the adit. Fractures naturally present or created from blasting and excavation increase the reactive surface area. Morth et al. (1972) found fractures oxidizing up to 15m behind the visible mine wall. Use of this technique will inform the decision-making process in relation to adit discharge as well as any adaptive management required.

of 85

References

Amax Northwest Mining Company Ltd. 1976. Environmental Report on the Macmillan Tungsten Property. Amax Inc. Environmental Services Group. Denver. Bradl, Heike. 2005. Heavy Metals in the Environment: Origin, Interaction and Remediation. Elsevier/Academic Press, London. Canadian Council of Ministers of the Environment. 1999. Canadian Water Quality Guidelines for the Protection of Aquatic Life. Manitoba Statutory Publications. Winnipeg. Canadian Council of Ministers of the Environment. 2001. Canadian Sediment Quality Guidelines for the Protection of Aquatic Life. Manitoba Statutory Publications. Winnipeg. Canadian Council of Ministers of the Environment. 2003. Guidance on the Site-Specific Application of Water Quality Guidelines in Canada. Manitoba Statutory Publications. Winnipeg. Dameron, C. and P.D. Howe. 1998. Copper –Environmental Health Criteria. International Programme on Chemical Safety. Available from: http://www.inchem.org/documents/ehc/ehc/ehc200.htm Davies, D.J. and C.D. Shepard. 1981. Preliminary Fisheries Report for North Canol Road. Department of Indian Affairs and Northern Development. 1982. Initial Environmental Evaluation for the Reconstruction of the North Canol Road. Document reference 2008-0242-058-1. Submission from Department of Fisheries and Oceans. YESAB Online Registry. Elson, M. 1974. Catalogue of Fish and Stream Resources of East Central Yukon Territory. Fisheries and Marine Services of Environment Canada. Technical Report Series PAC-74-4. Environmental Protection. 2000. Water Chemistry and Sediment Metal Sampling at Tom Adit, Sekie Creek #2, South Macmillan River, Sekie Creek #1 and Macintosh Creek. Environmental Protection. 2006. Water Chemistry and Sediment Metal Sampling at Tom Adit, Sekie Creek #2, South Macmillan River, Sekie Creek #1 and Macintosh Creek.

http://www.inchem.org/documents/ehc/ehc/ehc200.htm

of 85

Environment Canada. Land Use Information Services. Maps 105-F, 105-J, 105-K, 105-O. Ottawa, 1973 and 1974. Environment Canada. 1994. Priority Substances List Report: Nickel and Its Compounds. Environment Canada, Ottawa. Geological Survey of Canada, 2004. Earthquake Monitoring Network. As found on the YESAB Geolocator. Jack M.E. and T.R. Osler. 1983. Regional Program Report No. 83-08 - Baseline study of the watersheds near the Jason Property, Macmillan Pass, Yukon Territory. Department of Indian and Northern Development. Water Resources Branch. Gomez-Caminero, A., P. Howe, M. Hughes, E. Kenyon, D.R. Lewis, M. Moore, J. Ng, A. Aitio and G. Becking. 2001. Arsenic and Arsenic Compounds -Environmental Health Criteria 224. 2nd ed. International Programme on Chemical Safety. Available from: http://www.inchem.org/documents/ehc/ehc/ehc224.htm Kwong J. and W.G. Whitley. 1992. Natural Acid Rock Drainage at Macmillan Pass, Yukon. DIAND Committee. DIAND MEND Project No. 11. McIntyre, J.K., D.H. Baldwin, J.P. Meador, and N.L. Scholz. 2008. Chemosensory Deprivation in Juvenile Coho Salmon Exposed to Dissolved Copper under Varying Water Chemistry Conditions. Environmental Science and Technology. 42: 1352 – 1358. Morth et al. 1972. Pyrite Systems: A Mathematical Model, Contract Report for the U.S. Environmental Protection Agency, EPA-R2-72-002. Nieboer, E., B.L. Gibson, A.D. Oxmand, and J.R. Kramer. 1995. Health Effects of Aluminum: A Critical Review with Emphasis on Drinking Water. Environmental Reviews 3: 29-81. Reid, Crowther and Partners. 1982. Fish Resource Survey North Canol Road. Simon-Hettich, B., A. Wibbertmann, D. Wagner, L. Tomaska, and H. Malcolm. 2007. Zinc-Environmental Health Criteria 221. International Programme on Chemical Safety (2001). Available from: http://www.inchem.org/documents/ehc/ehc/ehc221.htm Smith, C.A.S., Meikle, J.C., and Roots, C.F.(editors). 2004. Ecoregions of the Yukon Territory: Biophysical Properties of Yukon Landscapes. Agriculture and Agri-Food Canada, PARC Technical Bulletin No. 04-01, Summerland, British Colombia. SOR/2002-222. 2002. Metal Mining Effluent Regulations. Queen’s Printer for Canada.



of 85

Soroka I.K. and M.E. Jack. 1983. Regional Program Report No. 83-14 – Baseline study of the watersheds near the Tom Property, Macmillan Pass, Yukon Territory. Environment Canada. Statutes of the Yukon. 2003. Waters Act, S.Y. 2003, c.19. Queen’s Printer for the Yukon. Taub, F.B. 2004. Biological Impacts of Pollutants on Aquatic Organisms. University of Washington College of Ocean and Fishery Sciences, Seattle, WA. World Health Organization. 2007. Lead – Environmental Effects –Environmental Health Criteria 85. International Programme on Chemical Safety (1989). Available from: http://www.inchem.org/documents/ehc/ehc/ehc85.htm World Health Organization. 2007. Lead – Environmental Health Criteria 3. International Programme on Chemical Safety (1977). Available from: http://www.inchem.org/documents/ehc/ehc/ehc003.htm Wright, D.A. and P. Welbourn. 2002. Environmental Toxicology. Cambridge University Press, Cambridge, U.K.



of 85

APPENDIX I - SUMMARY OF RESPONSES FROM INTERESTED PERSONS AND OTHERS

Comment Summary Consideration for Use

YG Department of Tourism – Heritage Resources (document reference: 2008-0242-055-1)

• Project activities are confined to previously disturbed areas. • There are no historic resources concerns with the proposed project.

• Information

YG Department of EMR – Mineral Resources (document reference: 2008-0242-055-1)

• This is a request for an amendment to Water Licence No. QZ99-046. • All terrestrial activity falls within Class 1 thresholds therefore a Mining Land Use Approval is not required.

• Information

Fisheries and Oceans Canada (document reference: 2008-0242-058-1)

• As requested, Fisheries & Oceans Canada has reviewed the project description for the Installation of an Adit Plug and Associated Workings – Tom Valley Property, provided by your office pursuant to subsection 55(4) of the Yukon Environmental and Socio-economic Assessment Act. Our review of this project was limited to an evaluation of possible effects to fish and fish habitat.

• The area surrounding Sekie Creek #2, tributary of the South MacMillan River, is known to support fisheries resources. Arctic Grayling, Northern Pike, Burbot and Slimy Sculpin are present in the area along with Juvenile Chinook Salmon identified downstream and there is the potential for these species to be negatively impacted by the resulting water quality from the proposed discharge.

• Section 32 of the Fisheries Act prohibits the killing of Fish by means other than fishing (i.e. poor water quality). • Section 36 of the Fisheries Act prohibits the introduction of a Deleterious Substance into a fish bearing stream and is administered by

Environment Canada on behalf of Fisheries and Oceans Canada. • This information is provided to the YESAB registry to provide necessary information for Environment Canada to determine the potential impacts

in respect to water quality and Section 36 of The Fisheries Act. As such, our Department is not a Decision Body in the assessment of this project. • Please note that this advice is provided to satisfy the requirements of subsection 55(4) of the Yukon Environmental and Socio-economic

Assessment Act and should not be taken to imply approval in accordance with the habitat protection provisions of the Fisheries Act or any other federal or territorial legislation.

• If you have any questions concerning the above, or if my understanding of the proposal is either incorrect, incomplete, or if there are changes to the proposed works or undertakings, please contact me directly by telephone at (867) 393-6785, or by fax at (867) 393-6737.

• Attachments: − Fisheries Resources in the Area of the Tom Valley Adit Project − Fish Resource Map

• Information • Information; “Aquatic

Resources” used as valued component.

• Information • Information • Information • Policy or position • Information • Information

Environment Canada (document reference: 2008-0242-062-1)

• Environment Canada has reviewed the information posted on the YESAB Public Registry to date for the above mentioned project. Given the nature of new information provided by the Department of Fisheries and Oceans on the fish distribution in the South MacMillan River we have the following comments:

• The Gartner Lee report entitled "Tom Valley Fisheries Assessment, 2007" Prepared for Hudson Bay Mining and Smelting Co., Limited, October 2007, indicated on page 8 that various studies conducted in early 1980 speculate that fish such as Arctic Grayling are likely to move upstream to

• Information

of 85


South Macmillan Bridge #2 and possibly as far up to Sekie #1 Creek. We consider the information provided by DFO (YESAB 2008-0242-059-2) as confirmation of the presence of fisheries resources as far as Dewhurst Creek Km 199 on the North Canol road.

• Our information on water quality indicates that through-out the early 1980's and onwards the South Macmillan river quality has been gradually degraded. We would like to point out the cumulative effects of adjacent Hudson Bay Mining property (Jason claims) on the west side of the Macmillan River (see attached map). One of the Jason property flowing drill hole discharge was 1.21 mg/l T. Zn on July 9, 1981 while values of the three flowing bore holes ranges from 1.14 to 12.1 mg/ T.Zn September 28, 2006. We provide you with some historical data to show water quality from reports conducted in 1981, (Soroka and Jack 1983; and Jack and Osler 1983); as well as Kwong and Whitley in 1992.

• We are concerned that anthropogenic activities on the property have over time degraded the water quality and are further concerned that the plugging of the adit and the flushing of already precipitated metals will aggravate this situation. We are similarly concerned that there appear to be no provisions for treatment of the discharge should values of zinc, for instance, raise beyond the expected levels and therefore zinc loading from Sekie Creek #2 increases as a result of the project.

• At this point we do not anticipate future impacts to resources that have already been suffering from natural and anthropogenic high metal loadings. We will be looking for regulatory limits and action plans to deal with those issues at the regulatory phase with the water licence.

• Attachments: − Jack M.E. and T.R. Osler. 1983. Regional Program Report No. 83-08 - Baseline study of the watersheds near the Jason Property,

Macmillan Pass, Yukon Territory. Department of Indian and Northern Development. Water Resources Branch. − Soroka I.K. and M.E. Jack. 1983. Regional Program Report No. 83-14 – Baseline study of the watersheds near the Tom Property,

Macmillan Pass, Yukon Territory. Environment Canada. − Kwong J. and W.G. Whitley. 1992. Natural Acid Rock Drainage at Macmillan Pass, Yukon. DIAND Committee. DIAND MEND Project

No. 11. − Macmillan pass Fig 1 − Macmillan pass Fig 2

• Information; “Water

Resources” used as a valued component

• Expert opinion;

potential project effects

• Expert opinion • Information

YFN Government Kaska: Ross River Dena Council – Testloa Smith (document reference: 2008-0242-064-1)

We have reviewed the project and we have the following comments: • We are concern that the plan to plug the audit may not be the way to go on this project. We need to have a more inform information on this plan.

We have had one meeting with the proponent and we where going to have some follow up meetings which did not happen as yet. We are concern that the water will come out in a different location.

• We are concern about the aquatic life in the main river system which has fish and other life. If the plug fails and we well have a bigger problems down stream and the will need some time to know all of this detail.

• Monitoring the site plan is needed as we have not seeing any treatment of this creek and we well need to see if the exposed area along the creek well be part of the plan to cover it. This where a machine has took and push the top soil near the creek this well need to be fixed.

• We can not support the project at this time for the reason mentioned above.

• Potential project effect • Potential project effect • Possible mitigation • Policy or position

Hudson Bay Mining and Smelting Co., Limited (document reference: 2008-0242-066-1)

• We note the December 2, 2008 correspondence from the Ross River Dena Council regarding our submission to the Yukon Environmental and Socio-economic Assessment process on the Tom Valley Adit plug project.

• Given the concerns expressed by the First Nation, we have instructed our environmental consultants to arrange meetings with the Council immediately so that Council’s concerns can be fully understood and answers provided to address these concerns.

• Information • Information

of 85


• Mr. Cameron and his associate, Kai Woloshyn will report back to me following this meeting and we will communicate with you on the outcome of the meeting with the First Nation and our intentions for engagement going forward.

• Hudson Bay Mining and Smelting Co., Limited is committed in working with the Ross River Dena Council as this project moves forward. We trust this immediate action will help in building a strong cooperative relationship with Ross River.

• Information • Policy or position

YG Department of Environment (document reference: 2008-0242-067-1)

Valued Ecosystem Components Improved water quality will prevent further degradation of downstream fisheries and aquatic resources. Bears are known to be present in the area and odours from camp will likely be an attractant. • Water Quality • Grizzly bears, black bears Water Quality Site water quality monitoring • Generally, the company has extended the monitoring program geographically to an acceptable level even though the frequency of sampling is

understandably limited. This will help to inform the anticipated request for site-specific water quality objectives based on background levels. • The calculation of loadings from surrounding tributaries and watersheds is very helpful to see the relative scale of metal movements. Waste Rock Dump • Monitoring of the waste rock dump seems to be limited by the amount/duration of water found in the wells. Environment would prefer to have

better data on this since it has long-term implications to water quality leaving the site. Improvement of existing wells or addition of new wells should be considered. The high variability of water quality found from two of the wells should be further explained.

• ARD assessment of the dump materials showed the metal leaching from the material was relatively high. • The company plans to recontour and cover 75% of the dump; given this amount of effort it seems that more could be done to find an innovative

way to cover, or otherwise seal, the remainder of the dump. • Preventing any further infiltration from adit water by using a lined discharge channel is a positive step. Keeping the dump as dry as possible is

important. Adit/Flooding • The choice of remedial options seems reasonable, as ongoing treatment would be expensive and technically difficult and would result in

additional environment effects (air quality, waste disposal). In light of the need for a plan to diminish oxidation rates, the hydraulic plug with pressure relief, combined with isolating the waste dump appears to offer a reasonable response.

• The company concedes that the initial water produced will be high in metals due to the flushing of contaminants from the workings. The company should submit a plan to deal with this in the short term. One option would be short-term water treatment during this flushing phase. The company has not provided any predictions of how long this flushing phase will last; and thus costs and impacts of water treatment are difficult to predict.

• The company is not confident that the geologic structure will handle the additional pressure; it seems reasonable to expect that new seeps will develop. It may be necessary to grout or otherwise re-route such seeps should they occur. Unfortunately, the type of mitigation using a relief drift does not lend itself to a trial, as it cannot be done in stages. The company may wish to investigate using shot-crete or other material to seal weak

• “Wildlife and Wildlife

Habitat” will be used as valued component

• Policy or position • Possible mitigation • Information • Possible mitigation • Information • Information • Potential project

effect; possible mitigation

• Potential project

effect; possible mitigation

of 85


areas of the internal surfaces of the adit prior to flooding. • Data provided by the proponent indicates that, in the long term, water quality from the flooded adit should improve to near or slightly better than

background surface water concentrations. This is based on results of water sampling in the flooded portion of the adit. In the long term, therefore, flooding of the adit appears to be an appropriate mitigation approach for this site.

• The water quality model provided for parameter loadings during the flushing phase uses the historic downstream loading the each parameter, and then adds to that the loadings of adit discharge (ref. Q16.a, page 10, May8/08). The historic downstream WQ values already include adit waste, therefore this appears to have the effect of adding the adit loading twice. These values should be reviewed and possibly recalculated.

• Further to the response to Q. 16.a., the proponent states that the long term phase water quality modeling used the maximum and 95th percentile concentrations of background to predict long-term adit water quality. It is not stated in this discussion why existing surface water quality is an appropriate benchmark for adit water quality. A more appropriate benchmark for this calculation may be water in the already-flooded workings of the decline.

Fisheries • There has been some effort given to fish habitat assessment, and further information (provided by DFO) has identified Sekie Creek as fish-

bearing although of only moderate quality. Since the resource is so limited, this assessment will have limited usefulness for determining ecosystem health (though we know poor water quality is obviously causal).

• Anecdotal information suggests that recreational pressure in the immediate area of the project is very limited – however Sekie Creek likely acts as rearing habitat to support populations in the South MacMillan River, where there is some recreational and traditional use.

• Effects on fish resulting from historic activity is likely significant given the poor water quality of adit drainage, particularly the low pH and loading of dissolved metals. Given that the goals of the project are to improve water quality from the site, the effects of the project should be generally positive. From the information provided, Environment is not able to determine what site-specific standards would be suitable from a fisheries perspective. Therefore, it would be safest to resort to the CCME standards which are based on protection of aquatic life.

Bears – garbage management • Bears commonly utilize valley bottom and stream corridors as travel routes, as well as alpine and sub-alpine areas. Mining exploration activities,

including the location of long term seasonal camps, usually are situated in similar settings. Such activities associated with noise from heavy equipment may cause disturbance and avoidance of wildlife to the area; however without threat or danger, wildlife can become accustomed to routine noise.

• The likelihood of bear visitation to mining camps, increases exponentially over the duration of the spring, through fall exploration season, versus a short-term camp of several days, whether or not appropriate garbage handling is maintained. The likelihood of bears repeatedly visiting a camp is directly linked to whether they obtain a food reward from inadequate garbage management or are immediately deterred on first contact with the site. Bears constantly assess risk and reward situations and when adequate deterrent (risk) is applied, bears usually will stay away from camps. Conversely, bears conditioned to seeking food at camps become increasingly bold and often are killed in protection of property or life, resulting in direct wildlife mortality as an adverse effect of the project.

• Remoteness of a project has no validity to conditioning bears to human presence. Bears can very easily become accustomed to human activities in a populated area, such as urban neighborhoods in the City of Whitehorse, as easily as a remote area and once realizing human activities are not a threat, are not deterred due to routine activities and noise.

• In order to reduce the potential for bear/human conflicts and/or property damage, garbage, including kitchen waste must be handled so as not to become accessible to bears. Bear deterrent devices also should be kept in camp, such as bear pepper spray, air horns (devices emitting loud noises), rubber bullets commercially manufactured to use with 12 gauge shotguns and ideally, electrified fencing around the camp perimeter,

• Expert opinion • Expert opinion • Expert opinion • Information • Information • Expert opinion • Information; potential

project effects • Information; potential

project effects • Information • Information; possible

mitigation

of 85


particularly food preparation/storage areas and garbage handling area. (The cost of a portable, reusable electrified bear fencing unit is approximately the same cost as a new wall tent – trashed contents and human injury excluded). Such devices may effectively scare off a bear during its initial contact with human activities, rather than establishing a situation where a habituated bear is killed. The proponent should contact the district Conservation Officer for information concerning appropriate garbage handling and bear deterrent devices.

Environment recommends the following mitigation to reduce the potential for human bear interaction: • The proponent shall keep all garbage, including kitchen waste, in a container that prevents access by bears and other wildlife, until properly

disposed of in accordance with the Solid Waste Regulation. • When burning kitchen waste on site, it must be burned regularly to reduce odours that might attract wildlife and be burned to ash by forced air or

fuel fired incineration.

• Possible mitigation • Possible mitigation

YG Department of Community Services (document reference: 2008-0242-019-1)

• Prior to the placement or construction of any building on the site, development, building, plumbing, and/or electrical permits will be required from Yukon Government Consumer and Safety Services.

• Suggest completing a Fire Smart treatment around any structure.

• Information • Policy or position

YG Department of EMR – Land Use Branch (document reference: 2008-0242-019-1)

• A Quarry Permit is required. A Quarry Permit application needs to be submitted to the Lands Branch with the location of the pit, quantity of material and fees. This application needs to be reviewed by the Department of Highways & Public Works to determine if the location is suitable before a permit can be issued.

• Information

YG Department of Environment (document reference: 2008-0242-019-1)

Valued Ecosystem Components Improved water quality will prevent further degradation of downstream fisheries and aquatic resources. Bears are known to be present in the area and odours from camp will likely be an attractant. • Water Quality • Grizzly bears, black bears Water Quality Site water quality monitoring • Generally, the company has extended the monitoring program geographically to an acceptable level even though the frequency of sampling is

understandably limited. This will help to inform the anticipated request for site-specific water quality objectives based on background levels. • The calculation of loadings from surrounding tributaries and watersheds is very helpful to see the relative scale of metal movements. Waste Rock Dump • Monitoring of the waste rock dump seems to be limited by the amount/duration of water found in the wells. Environment would prefer to have

better data on this since it has long-term implications to water quality leaving the site. Improvement of existing wells or addition of new wells should be considered. The high variability of water quality found from two of the wells should be further explained.

• Policy or position • Policy or position • Expert opinion

of 85


• ARD assessment of the dump materials showed the metal leaching from the material was relatively high. • The company plans to recontour and cover 75% of the dump; given this amount of effort it seems that more could be done to find an innovative

way to cover, or otherwise seal, the remainder of the dump. • Preventing any further infiltration from adit water by using a lined discharge channel is a positive step. Keeping the dump as dry as possible is

important.

Adit/Flooding • The choice of remedial options seems reasonable, as ongoing treatment would be expensive and technically difficult and would result in

additional environment effects (air quality, waste disposal). In light of the need for a plan to diminish oxidation rates, the hydraulic plug with pressure relief, combined with isolating the waste dump appears to offer a reasonable response.

• The company concedes that the initial water produced will be high in metals due to the flushing of contaminants from the workings. The company should submit a plan to deal with this in the short term.

• The company is not confident that the geologic structure will handle the additional pressure; it seems reasonable to expect that new seeps will develop. It may be necessary to grout or otherwise re-route such seeps should they occur. Unfortunately, the type of mitigation using a relief drift does not lend itself to a trial, as in it cannot be done in stages. The company may wish to investigate using shot-crete or other material to seal weak areas of the internal surfaces of the adit prior to flooding.

2008 Field Program • Environment looks forward to the results of the proposed 2008 studies, to determine adit water sources (meteoric vs. deep ground). These may

inform adaptive changes to the project. • There has been effort given to fish assessment. Since the resource is so limited, this assessment will have limited usefulness for determining

ecosystem health (though we know poor water quality is obviously causal). It would be valuable to have an assessment of benthic organisms based on CCME’s new CABIN protocol which is now recognized nationally as a useful tool.

Bears – garbage management • Bears commonly utilize valley bottom and stream corridors as travel routes, as well as alpine and sub-alpine areas. Mining exploration activities,

including the location of long term seasonal camps, usually are situated in similar settings. Such activities associated with noise from heavy equipment may cause disturbance and avoidance of wildlife to the area; however without threat or danger, wildlife can become accustomed to routine noise.

• The likelihood of bear visitation to mining camps, increases exponentially over the duration of the spring, through fall exploration season, versus a short-term camp of several days, whether or not appropriate garbage handling is maintained. The likelihood of bears repeatedly visiting a camp is directly linked to whether they obtain a food reward from inadequate garbage management or are immediately deterred on first contact with the site. Bears constantly assess risk and reward situations and when adequate deterrent (risk) is applied, bears usually will stay away from camps. Conversely, bears conditioned to seeking food at camps become increasingly bold and often are killed in protection of property or life, resulting in direct wildlife mortality as an adverse effect of the project.

• Remoteness of a project has no validity to conditioning bears to human presence. Bears can very easily become accustomed to human activities in a populated area, such as urban neighborhoods in the City of Whitehorse, as easily as a remote area and once realizing human activities are not a threat, are not deterred due to routine activities and noise.

• In order to reduce the potential for bear/human conflicts and/or property damage, garbage, including kitchen waste must be handled so as not to

• Information • Possible mitigation • Expert opinion • Expert opinion • Potential project

effects; possible mitigation

• Policy or position • Basis for information

request • Information; potential

project effects • Information; potential

project effects • Information • Information; possible

of 85


become accessible to bears. Bear deterrent devices also should be kept in camp, such as bear pepper spray, air horns (devices emitting loud noises), rubber bullets commercially manufactured to use with 12 gauge shotguns and ideally, electrified fencing around the camp perimeter, particularly food preparation/storage areas and garbage handling area. (The cost of a portable, reusable electrified bear fencing unit is approximately the same cost as a new wall tent – trashed contents and human injury excluded). Such devices may effectively scare off a bear during its initial contact with human activities, rather than establishing a situation where a habituated bear is killed. The proponent should contact the district Conservation Officer for information concerning appropriate garbage handling and bear deterrent devices.

• Environment recommends the following mitigation to reduce the potential for human bear interaction: • The proponent shall keep all garbage, including kitchen waste, in a container that prevents access by bears and other wildlife, until properly

disposed of in accordance with the Solid Waste Regulation. • When burning kitchen waste on site, it must be burned regularly to reduce odours that might attract wildlife and be burned to ash by forced air or

fuel fired incineration.

mitigation • Possible mitigation • Possible mitigation

YG Department of Tourism – Heritage Resources (document reference: 2008-0037-019-1)

• The project occurs in a previously disturbed area. No historic resources concerns. • Information YG Department of Tourism and Culture

(document reference: 2008-0037-019-1) • No known tourism concerns with this project. • Information


Environment Canada has had an opportunity to review the project proposal but none of the appendices for the above mentioned project information were reviewed. While our review is incomplete and preliminary, we are offering the following comments and questions before the closing date of the “Seeking views and information.” • Will there be active enhancement of the metal precipitation through lime neutralization or carbon sources for sulphate reduction during the initial

adit flooding? • What is the anticipated geology for the rock material the adit bypass raise will be contrasted within? • Will there be ARD issues arising from the bypass? • Should that be the case, what mitigation will be in place to reduce new and additional sulphide oxidation? Sludge containment: The report suggests that the sludge containment pond will be sized for twice the sludge and waste water containment volume, yet our review of the calculations indicates the volume closely matches the stated volume of waste with minimal provided freeboard. • How will the project transfer the indicated waste to the sludge pond while the adit continues to flow at 10 L/s? • How will the pond inhibit loss of metal precipitates during high rain events prior to the cover establishment? • Will there be a liner above the sludge before the waste rock cover? • How will the waste rock sustain frequent debris flow? • What are the frequencies of debris flow in the vicinity of the workings? • Will the increased water pressure from the adit plug increase the infiltration of water North of the adit and into the waste rock pile? • How will the monitoring program adequately evaluate the effect of the infiltration and changes in water quality in the water rock pile? • If the adit has promoted draining of the local hillside, and thereby possibly changed oxidation deeper within the hillside with development of

• Information; all questions in this submission were the basis for an information request

of 85


more ARD/ML products, will re-establishing a higher groundwater table lead to flushing of stored products which have developed during the past 30 years?

Table 5-3 and 5-2: • What is the relationship between flow and concentrations? • The relationship cannot be seen from the re-worked statistics. We may have a difficult time accepting some of the stations listed in these tables

as “background” when they have site features located upgradient of them or are otherwise closely related to a constructed feature – for instance “Adit Seep” is taken from within the workings, and normally this would be treated as a relict of water interacting with “freshly exposed” rock under conditions which are perfect for enhanced ARD/ML processes.

Section 5.8.3 indicates high metal concentration in seeps downgradient from the dump. • What effect will the plug and establishing/re-establishing higher groundwater condition in the hillside have on the seeps quality and quantity as

water flows through the waste rock dump? • Is there an expectation of additional seep sources appearing as a result of the flooded underground condition, will this be monitored? • What is the estimate for lost waste rock as a result of the adit blow out (ice plug failure) and the erosion of a portion of the waste rock dump into

Sekie Creek? • Is it possible that the material is also contributing to the “non-point source” zinc loading downstream of the adit? • The report mentions that ore was extracted from the underground. What was the final resting location for this material – where was it placed? • Are the underground workings hydraulically connected to the water stations downstream of W5 and upstream of W8, hence the increase in

loading? • Given the fault structures and underground working indicated on the plan, is there a possible connection between the underground workings and

Sekie and Tom Creeks upstream of the adit? Maps which provide the full information with respect to major faults projected to surface, combined with the surface drainage and sampling stations, and other major features could assist with the assessment. Cross-sections indicated on the Figure 4-2 may be helpful. The BH01-05 groundwater monitoring well: • Are there any exposed mine workings directly upgradient of the monitoring well? • There is mention in the text of an exploration drillhole located in the creek yet it is not indicated on any map – where is this located and what is

the connection and significance with respect to the orebody and underground workings? The geochemical testing program for the adit rock samples included a shake flask program using adit water as the extraction liquid. What was the water quality for the adit water? While using adit water as the extractant may provide some indication of initial flushing conditions, we wonder if instead an alternate protocol such as EPA 1312 would provide better information to indicate long-term release conditions. We question the results and interpretation for the ABA analysis of waste rock samples. Discussion over BH04-05 provides and example: the composite sample indicates a positive bulk NP (12.2) while each of the intervals making up that composite reported negative bulk-NP’s–similarly with the NPR’s (as well Total sulphur appears to be wrongly presented on Table 5-10). Interval information (depth, drill hole log/mineralogy) should be presented in Table 5-10.

of 85


• What will be used to prevent/mitigate the flushing of dissolved metals from the adit to the environment? • We noticed that section 8.1:2 does not mention a backup mitigation plan. The modeling indicates that predicting the water quality as a result of

the adit plug proposal can be challenging. What are the plans to mitigate should the monitoring program show metal levels higher than expected? In section 9.3, excessive seepage can be viewed as an impact especially if that seepage increases the infiltration rate through the waste rock dump. • How would that effect be mitigated?

YFN Government Kaska: Liard First Nation – David Dickson (document reference: 2008-0037-024-1)

• The Liard First Nation today (2008) is an amalgamation from various other First Nations… RRDC members, Pelly Lake Band members, Francis Lake Band members, Muncho Lake Band members, and the Dease River First Nation members, they all are included in the Liard First Nation Band membership list…

• Today the descendants of these above mentioned Bands still harvest fur, hunt and practice their cultural rights in their traditional areas, including the area affected by the project.

• As an amalgamated First Nation, the Liard First Nation has the fiduciary duty and the legal responsibility to act in the best interest of its members. If there are any development in the traditional areas of the above mentioned amalgamated members… Development Companies are required to consult with LFN.

• Information • Information • Information

YFN Government Kaska: Liard First Nation – Laurie Allen (document reference: 2008-0037-025-2)

• Further to the June 12, 2008 submission by David Dickson, all proponents are advised to contact me for the purpose of arranging for consultations related to the interests of the Liard First Nation. To avoid any confusion on the part of government, proponents or YESAB, any consultation with the Liard First Nation has no affect on a proponent's responsibilities, or those of government, to also consult with the Ross River Dena Council, as they may require.

• Information

YFN Government Kaska: Ross River Dena Council – Testloa Smith (document reference: 2008-0037-026-1)

• We have reviewed the application and have had a meeting with the company representative in which we had the understanding that further meetings will be had on these concerns which are: consultation with the First nation will be done on the progress and development on the project to insure our input. We will have more discussion on the plug and the water monitoring. Other opportunity will also be on the agenda in future meeting. With these understand on this we support the project.

• Information


• Thank you for arranging a meeting with the Hudson Bay Mining and Smelting Company’s consultant (Gartner Lee) to discuss of the above project.

• The meeting today mostly focused on the hydrogeology and implications of the adit plug on water quality, and acid rock drainage. We would like to follow-up with some points that were made at the meeting and provide suggestions for the screening. We understand that further information will be forthcoming as a result of your information request of July 8, 2008.

• We were not aware of the drill hole at elevation 1574m on Sekie#2 which shows artesian condition. The drill hole is located at the most upstream station on Sekie#2 creek. The company should provide water quality information and flow data for that site. We are concerned that the station W3 has been influenced over the years by this artesian well.

• We are concerned about the presence of sludge in the West zone and the amount present in the underground workings. The sludge should be

• Basis for information

request • Expert opinion • Expert opinion

of 85


analysed for metals and an evaluation of the material upon flooding conditions be determined. The sludge under flooding conditions should be added to the water quality model under construction.

• We are concerned that the 20 m raise in the West Zone underground working will influence the water quality ofW3 and W3A stations. A fault zone close to 1445.17m in the West Zone may provide a conduit to the surface station W3A at 1455 m elevation, below the flooding level.

• The overlay map of the surficial features and Underground workings were very instructive. The same approach should be performed for the geological structures on the property and all surface disturbances. We also noticed that the camp located upgradient of the Tom Creek and Sekie #2 confluence seemed to be constructed on fill material. Please provide more information on the nature of the material and origin.

• We suggest isotope ratio analysis to determine groundwater sources differentiation between meteoric water vs deep groundwater system in order to help understanding groundwater movements.

• We suggest plugging all drill holes on the property at least the ones below the predicted flood elevation. • Our understanding of initial flushing of mine workings is about 4 to 5 time the flooding rate of the mine workings. At this time we are not in

position to speculate about the peak concentrations. The W5 total zinc value as reported in Appendix C2 showed values from 10.5 to 30.1 mg/l with an average of 22.9 mg/l. These values were taken for the samples collected from 2000 to 2007. However the values were quite different in table 2 of Appendix A from the report "Tunnel Plug construction and Grouting -March 17, 2008, where the historical values (1978 to 1998) for W5 ranged from 0.14 to 11.8 mg/l. obviously the adit water quality has deteriorated over the years. While Gartner Lee suggested that the 30 mg/l maximum values be use as a threshold we see this value far from the Water Board deferred clause 17 of 1 mg/l T. Zn, and from the historical background concentrations. The company should provide an adaptive management approach to deal with potential high zinc concentrations and loads. We suggest that the company instigate one of the alternative treatments in conjunction of the adit plug system to achieve a reduction of zinc loading in Sekie #2.

• Should you have any questions, please do not hesitate to contact me at (867) 667-3402.

• Basis for information

request. • Basis for information

request; possible mitigation

• Possible mitigation • Expert opinion • Possible mitigation

of 85

APPENDIX II – ANALYSIS OF WATER QUALITY DATA Table 1 – Comparison of Water Quality Standards and Predictions

1 – Canadian Council of Ministers of the Environment – Canadian Water Quality Guidelines for the Protection of Aquatic Life, 1999. 2 – Metal Mining Effluent Regulations, 2002. 3 – Yukon Contaminated Site Regulations, 2002. 4 – Effluent Quality Standards as per current water licence (QZ08-080). 5 – Summary of Adit Discharge (taken from sample station W5 from 2000 - 2008 and presented with min, median and max concentrations). 6 – Flushing concentration range (predicted from minimum and maximum concentrations from Shake Flask extraction of adit wall rock with adit discharge water). 7 – Short-term concentration range (predicted from minimum and median concentrations of adit discharge from 2000 – 2008). 8 – Long-term concentration range (predicted from median to maximum concentrations compiled from Sekie Creek #2 and Macintosh Creek sample stations from 2000 – 2008). 9 – 95th percentile of long term predictions is the proposed long term water quality standard once conditions have stabilized.

Water Quality Standards Predicted Water Quality Parameter Unit CCME 1 MMER 2 CSR 3 EQS 4 Adit Discharge 5 Flushing 6 Short Term 7 Long Term 8

Physical Parameters

95th percentile

Flow L/s 5, 10, 23.8 n/a 5 – 10 23 – 156 n/a pH pH 6.5 – 9 2.0, 3.4, 4.0 2.1 – 3.1 2.0 – 3.3 3.2 – 5.0 4.1 Conductivity uS/cm 986, 1437, 3288 2084 – 5124 986 – 1454 749 – 2333 1869 Acidity mg/L CaCo3 302, 519, 1720 938 – 2800 302 – 540 261 – 1760 1299 Sulphate mg/L 155, 830, 1530 1300 – 3200 155 – 910 299 – 1890 1307 Metals Total Aluminum mg/L 0.005 – 0.1 18.9, 34.3, 107 91.8 – 117 18.9 – 38.1 30.9 – 158 141 Total Arsenic mg/L 0.005 1.00 0.05 0.0176, 0.036, 0.06 0.008 – 0.429 0.0176 – 0.036 0.005 – 0.097 0.045 Total Cadmium mg/L 0.000017 0.0006 0.018, 0.06, 0.109 0.0782 – 0.488 0.018 – 0.063 0.0781 – 1.52 0.626 Total Chromium mg/L 0.001 0.01 0.008, 0.0143, 0.064 0.028 – 0.135 0.008 – 0.0175 0.028 – 0.27 0.219 Total Copper mg/L 0.002 – 0.004 0.60 0.09 0.6 0.0177, 0.0389, 0.236 0.284 – 2.12 0.0177 – 0.0433 0.284 – 2.18 1.43 Total Iron mg/L 0.3 80, 133, 269 101 – 858 80 – 138 31.9 – 32 190 Total Lead mg/L 0.001 – 0.007 0.40 0.16 0.4 0.085, 0.0993, 0.128 0.0029 – 0.0663 0.085 – 0.1 0.01 – 0.169 0.05 Total Nickel mg/L 0.025 – 0.15 1.00 1.5 1 0.698, 1.05, 2.31 1.73 – 2.78 0.698 – 1.12 0.521 – 3.09 2.11 Total Selenium mg/L 0.001 0.01 <0.005, <0.01 0.004 – 0.023 0.0005 – 0.005 0.005 – 0.05 0.032 Total Silver mg/L 0.0001 0.015 <0.0002, 0.0005, 0.0005 0.00005 – 0.00164 0.00003 – 0.00023 0.00014 – 0.001 0.0008 Total Thallium mg/L 0.0008 0.003 <0.002, 0.0013, 0.0034 0.0054 – 0.0333 0.00095 – 0.0015 0.0011 – 0.004 0.004 Total Zinc mg/L 0.03 1.00 2.4 1 10.5, 22.9, 30.1 23.6 – 31.4 10.5 – 23.2 3.19 – 29.4 12.6 Dissolved Arsenic mg/L 1 0.0114, 0.0249, 0.036 0.008 – 0.429 0.0114 – 0.0238 0.005 – 0.064 0.0455

Results exceed CCME Aquatic Life Guideline Bold Results exceed CCME Aquatic Life Guideline and Water Licence EQS

of 85

Table 2 – Relative Water Quality in the Receiving Environment Based on Flushing, Short Term, Long Term Predictions and the Proposed Standard

1 – Summary of Adit Discharge (taken from sample station W5 from 2000 - 2008 and presented with min, median and max concentrations). 2 – Flushing concentration range (predicted from minimum and maximum concentrations from Shake Flask extraction of adit wall rock with adit discharge water). 3 – Receiving environment is station W13 – South Macmillan Bridge #2, the nearest downstream habitat where fish are considered to potentially be present. Values are shown in the order of peak, median and low flow conditions. 4 – Short-term concentration range (predicted from minimum and median concentrations of adit discharge from 2000 – 2008). 5 – Long-term concentration range (predicted from median to maximum concentrations compiled from Sekie Creek #2 and Macintosh Creek sample stations from 2000 – 2008). 6 – 95th percentile of long term predictions is the proposed long term water quality standard once conditions have stabilized.

Note – The short term predictions and associated water quality improvement were not included since the values used are the median adit discharge levels shown in column three. Water quality improvements calculated in the receiving environment for the short term also used these values. As such there would be no change to report.

Parameter Unit Adit Discharge 1

Flushing 2 Receiving Environment 3

Long Term 5

Receiving Environment

Proposed Standard 6

Receiving Environment

Physical Parameters

Flow L/s 5, 10, 23.8 n/a 23 – 156 n/a pH pH 2.0, 3.4, 4.0 2.1 – 3.1 3.2 – 5.0 4.1 Metals Total Aluminum mg/L 34.3 117 -1.46

-1.42 -5.38

158 -2.17 -2.11 -7.99

141 -1.93 -1.88 -7.13

Total Copper mg/L 0.0389 2.12 -6.28 -7.92 0.66

2.18 -5.39 -6.8

-29.84

1.43 -3.54 -4.46

-19.57 Total Nickel mg/L 1.05 2.78 -0.81

-1.15 -3.26

3.09 -0.81 -1.15 -3.26

2.11 -0.55 -0.79 -2.23

Total Zinc mg/L 22.9 31.4 -0.86 -0.85 -2.88

29.4 -0.65 -0.64 -2.18

12.6 1.11 1.10 3.73

Results exceed CCME Aquatic Life Guideline Bold Results exceed CCME Aquatic Life Guideline and Water Licence EQS

of 85

Table 3 – Comparison of Historical Adit Discharge, Receiving Environment and Proposed Standard

1 – Effluent Quality Standards as per current water licence (QZ08-080). 2 – Summary of Adit Discharge (station W5, 2000 – 2008 with min, median and max concentrations). 3 – Receiving Environment (station W13, 8.5km downstream at Macmillan River Bridge #2) 4 – 95th percentile of long term predictions is the proposed long term water quality standard once conditions have stabilized. Results exceed CCME Aquatic Life Guideline Bold Results exceed CCME Aquatic Life Guideline and Water Licence EQS

Parameter Unit EQS 1 Adit Discharge 2 Receiving Environment 3

Proposed Standard (95th percentile) 4

Physical Parameters

Flow

L/s 5 10

23.8

2280 10,265 28,300

n/a

pH pH 2.0 3.4 4.0

3.8 5.52 7.2

4.1

Conductivity uS/cm 986 1437 3288

162 233.5 355

1869

Acidity mg/L CaCo

3

302 519

1720

2.7 9.65 53.1

1299

Sulphate mg/L 155 830

1530

61.7 110 171

1307

Metals Total Aluminum mg/L 18.9

34.3 107

1.39 4.4

6.94

141

Total Arsenic mg/L 0.0176 0.036 0.06

0.0009 0.0012 0.003

0.045

Total Cadmium mg/L 0.018 0.06

0.109

0.0053 0.012

0.0273

0.626

Total Chromium mg/L 0.008 0.0143 0.064

0.0006 0.002

0.0057

0.219

Total Copper mg/L 0.6 0.0177 0.0389 0.236

0.008 0.022

0.0502

1.43

Total Iron mg/L 80 133 269

1.25 4.38 16.4

190

Total Lead mg/L 0.4 0.085 0.0993 0.128

0.0007 0.0012 0.005

0.05

Total Nickel mg/L 1 0.698 1.05 2.31

0.073 0.13

0.226

2.11

Total Selenium mg/L <0.005

<0.01

<0.001 0.002

0.0047

0.032

Total Silver mg/L <0.0002 0.0005 0.0005

<0.00002 0.000024 0.00033

0.0008

Total Thallium mg/L <0.002 0.0013 0.0034

<0.0002 0.00012 0.00013

0.004

Total Zinc mg/L 1 10.5 22.9 30.1

0.282 0.651

1.2

12.6

Dissolved Arsenic mg/L 1 0.0114 0.0249 0.036

<0.0005 0.0001 0.0002

0.0455

of 85

Note: The following figures provide a visual comparison between relevant water quality standards for each metal and the historical, predicted and proposed adit discharge. It represents the data from Appendix II Table 1. I used the higher value for any ranges within the CCME. I used the median value for adit discharge. And I used the maximum value for predicted discharges. Some of the standards do not apply to some of the metals and were removed in those cases. Finally, as the most conservative standard, the CCME is often not represented due to the concentration scale. Figure 1 – Comparison of Water Quality Standards for Aluminum with Historical, Predicted and Proposed Adit Discharge

0

20

40

60

80

100

120

140

160

180

Total Aluminum

Con

cent

ratio

n (m

g/L)

Standard - CCMEHistorical Adit Discharge Predicted FlushingPredicted Short TermPredicted Long TermProposed Standard

Figure 2 – Comparison of Water Quality Standards for Copper with Historical, Predicted and Proposed Adit Discharge

0

0.5

1

1.5

2

2.5

Total Copper

Con

cent

ratio

n (m

g/L)

Standard - CCMEStandard - Metal Mining Effluent RegulationsStandard - Contaminated Site RegulationsStandard - Current Water LicenceHistorical Adit Discharge Predicted FlushingPredicted Short TermPredicted Long TermProposed Standard

of 85

Figure 3 – Comparison of Water Quality Standards for Iron with Historical, Predicted and Proposed Adit Discharge

0

100

200

300

400

500

600

700

800

900

1000

Total Iron

Con

cent

ratio

n (m

g/L)

Standard - CCMEHistorical Adit Discharge Predicted FlushingPredicted Short TermPredicted Long TermProposed Standard

Figure 4 – Comparison of Water Quality Standards for Lead with Historical, Predicted and Proposed Adit Discharge

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

Total Lead

Con

cent

ratio

n (m

g/L)


of 85

Figure 5 – Comparison of Water Quality Standards for Nickel with Historical, Predicted and Proposed Adit Discharge

0

0.5

1

1.5

2

2.5

3

3.5

Total Nickel

Con

cent

ratio

n (m

g/L)


Figure 6 – Comparison of Water Quality Standards for Zinc with Historical, Predicted and Proposed Adit Discharge

0

5

10

15

20

25

30

35

Total Zinc

Con

cent

ratio

n (m

g/L)


of 85

Figure 7 – Comparison of Water Quality Standards for Arsenic, Cadmium and Chromium with Historical, Predicted and Proposed Adit Discharge

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

Total Arsenic Total Cadmium Total Chromium

Con

cent

ratio

n (m

g/L) Standard - CCME

Standard - Contaminated Site RegulationsHistorical Adit Discharge Predicted FlushingPredicted Short TermPredicted Long TermProposed Standard

Figure 8 – Comparison of Water Quality Standards for Selenium, Silver, Thallium with Historical, Predicted and Proposed Adit Discharge

0

0.01

0.02

0.03

0.04

0.05

0.06

Total Selenium Total Silver Total Thallium

Con

cent

ratio

n (m

g/L) Standard - CCME

Standard - Contaminated Site RegulationsHistorical Adit Discharge Predicted FlushingPredicted Short TermPredicted Long TermProposed Standard

of 85

Figure 9 – Historical Trends in Hardness, Copper and Zinc at Sekie Creek #2

Hardness at Sekie #2 (mg CaCO3/L)

050

100150200250300350400450500

1980 1985 1990 1995 2000 2005 2010

Copper at Sekie #2 (µg/L)

0

50

100

150

200

250

300

1980 1985 1990 1995 2000 2005 2010

Zinc at Sekie #2 (µg/L)

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

1980 1985 1990 1995 2000 2005 2010

Data Sources:

Environmental Protection, 2000 Environmental Protection, 2006 Jack, M.E. and T.R. Osler, 1983 Kwong J. and W.G. Whitley, 1992 Soroka, I.K. and M.E. Jack, 1983

of 85

Figure 10 – Historical Trends in Hardness, Copper and Zinc at South Macmillan River (bridge #2, #3)

Hardness (mg CaCO3/L)

0

50

100

150

200

250

1980 1985 1990 1995 2000 2005 2010

Copper (µg/L)

0

10

20

30

40

50

60

70

80

1980 1985 1990 1995 2000 2005 2010

Zinc (µg/L)

0100200300400500600700800900

1000

1980 1985 1990 1995 2000 2005 2010

Data Sources:

Environmental Protection, 2000 Environmental Protection, 2006 Jack, M.E. and T.R. Osler, 1983 Kwong J. and W.G. Whitley, 1992 Soroka, I.K. and M.E. Jack, 1983

YESAA Designated Office Evaluation...

Documents

Transcript of YESAA Designated Office Evaluation...