EKATI Diamond Mine

DRAFT

EKATI Diamond Mine Site Specific Water Quality Objective for Molybdenum, 2011 February 2012 EKATI DIAMOND MINE SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011

February 2012 Project #64809501

Citation: Rescan. 2012. EKATI Diamond Mine: Site Specific Water Quality Objective for Molybdenum, 2011 . Prepared for BHP Billiton Canada Inc. by Rescan Environmental Services Ltd.: Yellowknife, Northwest Territories.

Prepared for:

BHP Billiton Canada Inc.

Prepared by:

Rescan™ Environmental Services Ltd. Yellowknife, Northwest Territories

EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Executive Summary

BHP Billiton Canada Inc. (BHP Billiton) operates the EKATI Diamond Mine (EKATI) located approximately 300 km northeast of Yellowknife, Northwest Territories, Canada. The mine site is in the southern Arctic ecoregion.

BHP Billiton is committed to minimizing the impacts of EKATI on the aquatic environment, and to sustainable management of the aquatic environment. BHP Billiton developed the Aquatic Effects Monitoring Program (AEMP) to document any changes that occurred following mine construction, operation, and expansion, and to provide early warnings of environmental changes. The AEMP at EKATI is a requirement specified in BHP Billiton’s Class A Water Licence (W2009L20001). The Water Licence lists effluent quality criteria for some substances; however, no criterion is listed for molybdenum.

The AEMP has indicated that molybdenum concentrations in some lakes and streams of the Koala Watershed have changed over time. Over the past nine years, total molybdenum concentrations in water of Leslie Lake (maximum of 0.114 mg/L) and Moose Lake (maximum of 0.113 mg/L) downstream of the Long Lake Containment Facility (LLCF) discharge have increased by two orders of magnitude from baseline levels (below detection limits of 0.001 mg/L). Molybdenum has also increased to a lesser extent in Nema Lake, also downstream of the LLCF (maximum of 0.047 mg/L). Stream water concentrations of molybdenum have similarly increased approximately 50 times when compared to baseline in the interconnecting streams LeslieMoose (maximum 0.075 mg/L) and MooseNero (maximum 0.063 mg/L). Molybdenum concentrations show no appreciable increase in water or sediment in the KingCujo Watershed, which receives a different discharge (King Pond Settling Facility) than those waterbodies of the Koala Watershed downstream of the LLCF.

Because of this increasing trend for molybdenum in the Koala Watershed, BHP Billiton commissioned a Tier I aquatic Ecological Risk Assessment (ERA) in 2006. This ERA included the derivation of shortterm (acute) and longterm exposure (chronic) site specific water quality objectives (SSWQOs) for molybdenum. The shortterm exposure SSWQO was 20 mg/L, and the longterm exposure SSWQO was 16 mg/L.

Since 2006, there have been numerous acute and chronic toxicity studies reported, along with several SSWQOs for molybdenum. BHP Billiton therefore commissioned an update of the 2006 SSWQOs for molybdenum. This report derives updated SSWQOs for molybdenum following 2007 CCME guidance that was not available when the 2006 SSWQOs were derived.

All available acute and chronic toxicity data on molybdenum were evaluated for inclusion in the SSWQO derivation. A total of 13 acceptable acute toxicity studies on 11 species were used to derive a short term SSWQO for EKATI (223 mg/L). The recommended shortterm SSWQO is designated only for use in shortterm exposures such as spills or shortterm (≤ 24 h) peaks in molybdenum concentrations in the aquatic environment.

In total, 15 acceptable chronic studies were available on 10 species, including a chronic algal test commissioned specifically for this study. The recommended longterm SSWQO was 19 mg/L, designated for use in water quality monitoring at EKATI. Current molybdenum concentrations in the Koala Watershed are approximately 100 times lower than this SSWQO and approximately 1000 times lower than the shortterm SSWQO.

BHP BILLITON CANADA INC. i EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Acknowledgements

This report was produced by Rescan Environmental Services Ltd. (Rescan) for BHP Billiton Canada Inc. (BHP Billiton). The report was written by Mark Whelly (M.Sc.) of Rescan, assisted with literature searches by Adam Chateauvert (M.Sc.). Statistical analyses and review were conducted by James Elphick (B.Sc.) of Nautilus Environmental. Project management and further reviews of this study were provided by Tonia Robb (Ph.D.), as directed by Marc Wen (M.Sc.). Report production was provided by Amanda Broda and graphics were prepared by Francine Alford. Independent technical review was provided by Peter M. Chapman (Ph.D.) of Golder Associates Ltd.

BHP BILLITON CANADA INC. iii EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Table of Contents

EKATI DIAMOND MINE SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011

Table of Contents

Executive Summary ...... i

Acknowledgements ...... iii

Table of Contents ...... v List of Figures ...... vii List of Tables ...... vii List of Appendices ...... vii

Abbreviations ...... ix

1. Introduction ...... 11 1.1 Background ...... 11 1.2 Objectives ...... 12

2. Review of Water Quality Benchmarks ...... 21 2.1 Background ...... 21 2.2 Existing generic Water Quality benchmarks ...... 21 2.3 Previous sitespecific Water Quality benchmarks ...... 23

3. Methodology ...... 31 3.1 Introduction ...... 31 3.2 Sitespecific Water Quality Objective Approaches ...... 31 3.2.1 Background Concentration ...... 31 3.2.2 Recalculation ...... 31 3.2.3 Water Effects Ratio ...... 31 3.2.4 Resident Species ...... 32 3.2.5 Selected Approach for the EKATI SSWQO Calculation ...... 32 3.3 Compilation of Existing Information ...... 32 3.3.1 Environmental Fate ...... 32 3.3.2 Toxicity Data ...... 32 3.3.2.1 Existing Water Quality Guidelines ...... 33 3.3.2.2 Literature Search ...... 33 3.3.2.3 Aquatic Toxicity Bioassay ...... 33 3.4 Evaluation of Relevant Toxicity Data ...... 33

BHP BILLITON CANADA INC. v SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011

3.4.1 Screening Aquatic Toxicology Studies ...... 33 3.4.2 Minimum Requirements for SSD Dataset ...... 35 3.4.3 SSD Data Selection ...... 35 3.5 Derivation of SSWQO ...... 36

4. Results ...... 41 4.1 Compilation of Existing Information ...... 41 4.1.1 Environmental Fate ...... 41 4.1.2 Acute Toxicity Data ...... 41 4.1.3 Chronic Toxicity Data ...... 41 4.1.4 Exposure and Toxicity Modifying Factors (ETMF) ...... 41 4.2 Evaluation of Relevant Toxicity Data ...... 42 4.2.1 Acute Data ...... 42 4.2.1.1 Unacceptable Studies ...... 46 4.2.1.2 CCME Acute Dataset Requirements ...... 47 4.2.2 Chronic Data...... 47 4.2.2.1 Chronic Toxicity Testing 2010 ...... 411 4.2.2.2 Unacceptable Studies ...... 412 4.2.2.3 CCME Chronic Dataset Requirements ...... 412 4.3 Derivation of SSWQO ...... 413 4.3.1 Acute SSD ...... 413 4.3.2 Chronic Species Sensitivity Distribution ...... 415

5. Uncertainty ...... 51 5.1 Introduction ...... 51 5.2 Relevance of the Toxicological Datasets ...... 51 5.2.1 Inclusion Criteria ...... 51 5.2.2 Duration Criteria ...... 52 5.2.3 Minimum Data Criteria ...... 52 5.2.4 Endpoints Used in SSD ...... 53 5.2.5 Suitability of Species ...... 53 5.2.6 Model Fit ...... 53 5.3 Bioavailability ...... 54 5.4 tolerance of Organisms ...... 54 5.5 Toxicity of Mixtures ...... 55

6. Summary ...... 61

References ...... R1

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List of Figures

FIGURE PAGE

Figure 1.11. Surface Water Flow through the EKATI AEMP Watersheds ...... 13

Figure 1.12a. Total Molybdenum Concentrations in Water at AEMP Lake and Stream Sites, 19942011 ...... 15

Figure 1.12b. Total Molybdenum Concentrations in Water at AEMP Lake and Stream Sites, 19942011 ...... 16

Figure 1.13. Total Molybdenum Concentrations in Sediment at AEMP Mid and DeepDepth Lake Sites, 19942011 ...... 17

Figure 4.31. Acute Species Sensitivity Distribution for Molybdenum at EKATI ...... 414

Figure 4.32. Chronic Species Sensitivity Distribution for Molybdenum at EKATI ...... 416

List of Tables

TABLE PAGE

Table 4.21. Acute Toxicity Studies Used in the Acute Species Sensitivity Distribution ...... 43

Table 4.22. Chronic Toxicity Studies Used in Deriving a Longterm Water Quality Objective ...... 48

List of Appendices

Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994 to 2011

Appendix B. Acute Toxicity Studies on Molybdenum Available From the Literature

Appendix C. Chronic Toxicity Studies on Molybdenum Available From the Literature

Appendix D. Chronic Algal Bioassay on Molybdenum Conducted in December 2010

Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software

Appendix F. Statistical Analysis of Chronic Species Sensitivity Distribution Using SSD Master Software

BHP BILLITON CANADA INC. vii EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Abbreviations

Terminology used in this document is defined where it is first used.

ACR Acute to Chronic Ratio AEMP Aquatic Effects Monitoring Program ANZECC/ARMCANZ Australian and New Zealand Environment Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand BC WQG British Columbia Water Quality Guideline CCME Canadian Council of Ministers of the Environment CL Confidence Limit

EC x Effective Concentration required to induce a x% effect ERA Ecological Risk Assessment ETMF Exposure and Toxicity Modifying Factor EQC Effluent Quality Criteria

HC 5 Hazardous Concentration for 5% of tested species, while protecting 95% of tested species

IC x Inhibition Concentration required to cause a x% effect

LC x Lethal Con centration to x% of organisms tested LLCF Long Lake Containment Facility LOEC Lowest Observ ed Effects Concentration MPC Maximum Permissible Concentration NOEC No Observ ed Effects Concentration PNEC Predicted No Effect Concentration RIVM Dutch National Institute of Public Health and the Environment SSD Species Sensitivity Distribution SSWQO Site Specific Water Quality Objective US EPA United States Environmental Protection Agency WER Water Effects Ratio WLWB Wek’eezhii Land and Water Board WQG Wat er Quality Guideline WQO Water Quality Objective WHO World Health Organization

BHP BILLITON CANADA INC. ix EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

1. Introduction

1.1 BACKGROUND BHP Billiton Canada Inc. (BHP Billiton) operates the EKATI Diamond Mine (EKATI) located approximately 300 km northeast of Yellowknife, Northwest Territories, Canada. The mine site is in the southern Arctic ecoregion.

BHP Billiton is committed to minimizing the impacts of EKATI on the aquatic environment, and to sustainable management of the aquatic environment. BHP Billiton developed the Aquatic Effects Monitoring Program (AEMP) to document any changes that occurred following mine construction, operation, and expansion, and to provide early warnings of environmental changes. The AEMP at EKATI is a requirement specified in BHP Billiton’s Class A Water Licence (W2009L20001). The Water Licence lists effluent quality criteria (EQC) for some substances; however, no criterion is listed for molybdenum.

Receiving water quality at EKATI is currently compared to generic national guidelines provided by the Canadian Council of Ministers of the Environment (CCME 2007a). These guidelines do not have any legal or regulatory weight, but are used as default receiving environment benchmarks – they are not themselves used as endofpipe discharge criteria. For some water quality variables, a sitespecific derivation is appropriate to modify the generic guideline value to be representative of local conditions and the biological community at site.

In 2006, as part of its adaptive management strategy, BHP Billiton commissioned a Tier I aquatic Ecological Risk Assessment (ERA) for molybdenum (Rescan 2006). The ERA evaluated the potential risks of molybdenum exposure to aquatic species in downstream lakes and streams of the Koala and KingCujo Watersheds, and provided a scientificallydefensible molybdenum concentration that would safeguard the environment. A Species Sensitivity Distribution (SSD) was used to determine shortterm and longterm water quality objectives (WQOs), 20 mg/L and 16 mg/L, respectively, using acute data and an application (safety) factor based on the approach used by the Australian and New Zealand Environment Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand (ANZECC/ARMCANZ 2000). Thus beginning in 2007, the interim longterm site specific water quality objective (SSWQO) for molybdenum (16 mg/L) was used as a benchmark for monitoring the receiving environment as part of the AEMP at EKATI (e.g., Rescan 2008)

The AEMP was designed to detect effects in the EKATI receiving environment within two major watersheds (Figure 1.11). In the Koala Watershed, the AEMP monitors lakes and interconnecting streams downstream of the Long Lake Containment Facility (LLCF), including the LLCF discharge (Surveillance Network Program station 161630), Leslie Lake, LeslieMoose, Moose Lake, MooseNero, Nema Lake, NemaMartine, Slipper Lake, SlipperLac de Gras, and two lake monitoring sites in Lac de Gras (S2 and S3) (Figure 1.11). Within the KingCujo Watershed, the AEMP monitors lakes and interconnecting streams downstream of the King Pond Settling Facility (KPSF) including the KPSF discharge (Surveillance Network Program station 161643), Cujo Lake, Cujo Outflow, ChristineLac du Sauvage, and two monitoring sites in Lac du Sauvage (LdS1 and LdS2) (Figure 1.11).

Although total molybdenum concentrations have recently declined in some lakes (2008 to 2011), concentrations remain greater than baseline values (Figure 1.12a). Over the past nine years, total molybdenum concentrations in waters of Leslie Lake (maximum 0.114 mg/L) and Moose Lake (maximum 0.113 mg/L) downstream of LLCF discharge have increased by at least two orders of magnitude from baseline levels (below detection limits of 0.001 mg/L). Concentrations have periodically exceeded the CCME (2007a) water quality guideline (WQG) for the protection of freshwater aquatic life (0.073 mg/L) in Leslie and Moose lakes between 2007 and 2011. Molybdenum concentration in Leslie and Moose lakes

BHP BILLITON CANADA INC. 11 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011 was greater than the CCME guideline value in April (underice) water samples only (Figure 1.12a). However, concentrations remain below the previouslyestablished interim SSWQO and below the upper range of natural background concentrations in Canada. Molybdenum concentrations have also increased in Nema Lake, but to a lesser degree (maximum 0.047 mg/L).

Stream water concentrations of molybdenum have increased approximately 50 times when compared to baseline in the interconnecting streams LeslieMoose (maximum 0.075 mg/L) and MooseNero (maximum 0.063 mg/L) (Figure 1.12b). A smaller increase has been observed in NemaMartine (maximum 0.029 mg/L) (Figure 1.12b). Total molybdenum concentration in water collected from LeslieMoose Stream in September 2011 was greater than the CCME (2007a) WQG of 0.073 mg/L (average of 4 replicates samples was 0.075 mg/L) however concentrations in all other Koala Watershed streams remain below the guideline value. Molybdenum concentrations generally range from below detection to 0.5 mg/L in Canadian waters (CCME 1999). Thus, they can naturally exceed the current CCME (2007a) national WQG.

There is evidence that molybdenum concentrations are increasing in middepth sediments of Moose, Nema and Slipper lakes, and deeper sediment of Leslie Lake (Figure 1.13). However, sediment molybdenum concentrations are of less concern than observed concentrations in the water column because bioavailability is typically greater in the water column than in sediments (Chapman 2008).

Contrary to the findings described for the Koala Watershed lakes, molybdenum concentrations show no appreciable increase in water or sediment in the KingCujo Watershed which, receives a discharge from the King Pond Settling Facility (Figures 1.11 to 1.13).

As indicated above, increasing molybdenum concentrations in the Koala Watershed lakes initiated the development of SSWQOs in 2006. However, since 2006, significant work has been published that provides additional acute and chronic toxicity data on molybdenum. The Nevada Division of Environmental Protection (NDEP 2008) commissioned the development of water quality criteria for molybdenum for surface waters in the State of Nevada. In 2009, additional acute and chronic bioassay results were obtained and incorporated to recommend water quality standards for molybdenum (GEI 2009). In 2010, additional chronic toxicity data for molybdenum were reported for nine species, five of which had no previous information, and a chronic water quality criterion for molybdenum was derived for use in Holland (De Schamphelaere et al. 2010).

The availability of new (post2006) chronic toxicity data from new sources (e.g., De Schamphelaere et al. 2010) indicated the need for an update of the 2006 EKATI molybdenum interim SSWQOs.

1.2 OBJECTIVES The primary objective of this study was to develop revised, updated SSWQOs for molybdenum. This report provides:

o a brief discussion of existing guidelines and sitespecific objectives relative to their applicability to EKATI (Section 2);

o a description of the methodology used in deriving the SSWQOs (Section 3);

o the results of a literature review of fate and behaviour, acute and chronic toxicity studies, along with new results from an algal chronic toxicity bioassay, and calculation of a shortterm and longterm SSWQOs (Section 4); and,

o a discussion of uncertainties related to each step of the process (Section 5).

Development of the SSWQOs for molybdenum at EKATI followed Canadian procedures for sitespecific benchmark calculations and updated methods for their development (CCME 2003, 2007b).

12 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012

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7180000 7177000 7174000 7171000 7168000 gis no. gis EKA-01-109 7165000 PROJECT # 0648-095 ILLUSTRATION # a30888w February 20, 2012

Koala Watershed Lakes 0.15

1616−30 (LLCF) Leslie Moose Nema Slipper S2 S3 0.10

April 0.05 July August September Total Molybdenum (mg/L)

Detection Limit CCME Guideline 0.00

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Year

King-Cujo Watershed Lakes 0.15

1616−43 (KPSF) Cujo LdS2 LdS1

0.10

April 0.05 July August September Total Molybdenum (mg/L)

Detection Limit CCME Guideline 0.00

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Year

Note: CCME guideline is 0.073 mg/L. The 2006 interim site specific water quality objective is 16 mg/L.

Figure 1.1-2a Total Molybdenum Concentrations in Water at AEMP Lake and Stream Sites, 1994-2011 PROJECT # 0648-095 ILLUSTRATION # a35810f February 20, 2012

Koala Watershed Streams 0.15

Leslie−Moose Moose−Nero Nema−Martine Slipper−Lac de Gras

0.10

June 0.05 July August September Total Molybdenum (mg/L)

Detection Limit CCME Guideline 0.00

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Year

King-Cujo Watershed Streams 0.15

Cujo Outflow Christine−Lac du Sauvage

0.10

June 0.05 July August September Total Molybdenum (mg/L)

Detection Limit CCME Guideline 0.00 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Year

Note: CCME guideline is 0.073 mg/L. The 2006 interim site specific water quality objective is 16 mg/L.

Figure 1.1-2b Total Molybdenum Concentrations in Water at AEMP Lake and Stream Sites, 1994-2011 PROJECT # 0648-095 ILLUSTRATION # a30889w February 20, 2012

Koala Watershed Mid-Depth Sediments 60

Leslie Moose 50 Nema Slipper S2

10 Total Molybdenum (mg/L) Detection Limit

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 King-Cujo Watershed Mid-Depth Sediments 60

Cujo LdS1 50

10 Total Molybdenum (mg/L) Detection Limit 0

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 Koala Watershed Deep-Depth Sediments 60

Leslie Slipper 50 S3

10 Total Molybdenum (mg/L) Detection Limit

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 Year Notes: Sorry Tonia, but I overwrote the old a30889w so I don’t know what the first note is! No deep-depth sediments are collected in the King-Cujo Watershed. Figure 1.1-3 Total Molybdenum Concentrations in Sediment at AEMP Mid- and Deep-Depth Lake Sites, 1994-2011 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

2. Review of Water Quality Benchmarks

2.1 BACKGROUND In Canada, guidelines are used as benchmarks for receiving environments, and do not have legal status. The terms guideline, criterion, trigger value and objective are used by different jurisdictions to generally refer to levels for specific chemicals that are considered safe (i.e., pose minimal risk) for the environment. In Canada, these terms are not equivalent to endofpipe permitted discharge limits or standards; they refer to water quality in receiving waterbodies.

Historically, WQGs have commonly been derived using the hazard quotient method, as described in CCME (1991). This method used the single most sensitive species endpoint and applied one or more safety factor(s) to provide a conservative estimate of a safe concentration, done separately for each chemical of interest in surface waters. The WQG provided a guideline that was generally applicable across a broad spectrum of environments. Its greatest weakness was that it relied heavily on the results of a single study on a single species and thus was generally overly conservative. However, in cases where limited studies were available, it might also not have provided adequate protection for all taxa.

In 2003, guidance for derivation of sitespecific WQGs was provided in CCME (2003). More recently, Environment Canada has updated the CCME (1991) protocol to include the use of SSD (cumulative distributions of toxicity endpoints for all species) (CCME 2007b). An SSD is created using either acute (brief exposure) or chronic (repeated or continuous exposure) endpoints. The SSD data are then fitted to a model that best fits the data distribution (particularly at the critical lower tail) to determine the concentration that is considered to be protective of 95% of tested species. This concentration is termed the HC 5 (hazard concentration to 5% of the tested species). Protection of 95% of species is considered acceptable to protect overall ecological structure and function, given ecological redundancy present in natural systems (CCME 2007b).

A shortterm HC 5 is derived using an acute SSD; its application is limited to shortterm exposures. A longterm HC 5 is derived using a chronic SSD and is applied to longerterm exposures. The advantage of using an SSD approach is that it uses a statistical distribution to determine a benchmark, rather than relying on the lowest endpoint (which may be overprotective or not sufficiently protective as noted above).

2.2 EXISTING GENERIC WATER QUALITY BENCHMARKS Several toxicity end points can be used in guideline development. The preferred acute endpoint to be used in acute SSD development is an LC 50 (the lethal concentration at which 50% of test organisms are expected to die) (CCME 2007b). For a chronic SSD, numerous chronic exposure toxicity data exist. Most preferred is the EC 10 or IC 10 (Effective or Inhibition Concentration required to induce a 10% effect in test organisms). The NOEC is the No Observed Effects Concentration (highest test treatment that shows no significant difference from controls). The LOEC is the Lowest Observed Effects Concentration (lowest test treatment that shows a significant difference from controls). The MATC is the Maximum Acceptable Toxicant Concentration (calculated as the geometric mean of the NOEC and LOEC).

The existing CCME WQG for molybdenum for the protection of freshwater aquatic life is 0.073 mg/L (CCME 2007a). This value was calculated based on the most sensitive chronic toxicity study available at

the time, a 28d LC 50 of 0.73 mg/L for rainbow trout (Oncorhynchus mykiss ) (Birge 1978), divided by a safety factor of 10. The primary concern associated with the current CCME WQG is that the study upon

BHP BILLITON CANADA INC. 21 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011 which the value is based has not been reproducible (Davies et al. 2005). Other studies in laboratory and field settings indicate a much higher toxic threshold for effects of molybdenum to rainbow trout (Goettl and Davies 1976; McConnell 1977; Ennevor 1993; McDevitt et al. 1999; Pickard et al. 1999;

Davies et al. 2005; De Schamphelaere et al. 2010). Birge (1978) and Birge et al. (1980) observed LC 50 values of 0.73 to 0.79 mg/L molybdenum whereas Davies et al . (2005), who repeated those experiments, reported a LOEC of 400 mg/L using the same methodology as Birge (1978), and 1000 mg/L following Environment Canada (1998) test methodology. De Schamphelaere et al. (2010) reported an

EC 10 value of 43.2 mg/L molybdenum for reduced biomass of rainbow trout for a similar, but longer exposure. These recent results indicate that this species is considerably less sensitive than reported by Birge (1978) and Birge et al. (1980). The results of Birge (1978) and Birge et al. (1980) are also suspect because full details of the methodology used and control performance have never been provided. Thus, the present CCME (2007a) WQG for molybdenum appears to be based on scientific studies that are not technically defensible. Specifically there is a weight of evidence from subsequent studies to suggest less sensitivity and the CCME’s (2007b) data requirements were not met.

The Ontario Ministry of Environment water quality objective (WQO) is also based on the results of the Birge (1978) study and employs a safety factor of 16, resulting in a chronic WQO of 0.040 mg/L (Swain 1986; Ontario MOE 1998). Thus, for the same reasons as those described above, the Ontario WQO does not appear to be technically defensible.

The British Columbia Ministry of Environment (BC MOE 2010) provides a maximum WQG of 2 mg/L for shortterm exposures and a 30day average WQG of 1 mg/L for chronic exposures. The BC WQG is based on a 96hr LC 50 of 70 mg/L as MoO 3 ( with water hardness of 20 mg/L) for the fathead minnow (Pimephales promelas) (Tarswell and Henderson 1960, reported in Swain 1986). The BC MOE used this

study as it was the lowest LC 50 found in the literature at the time. The BC WQG was derived by converting the LC 50 to 42 mg/L (converting 70 mg/L as MoO 3 to pure molybdenum) and then multiplying it by safety factors of 0.05 (for the Maximum WQG) and 0.02 (for 30d Mean WQG). The BC Max WQG is 2.1 mg/L rounded down to 2 mg/L, and the BC 30d Mean WQG is 0.84 mg/L, rounded up to 1 mg/L (based on five consecutive weekly samplings to arrive at a monthly average). A technical problem with the BC WQG is that the key study (Tarswell and Henderson 1960) cannot be verified because it does not provide sufficient information regarding control survival and test methodology. Thus, the BC MOE WQG does not appear to be technically defensible based on the CCME (2007b) data quality requirements.

The Dutch National Institute of Public Health and the Environment (RIVM) developed a maximum permissible concentration (MPC) of 0.29 mg/L for molybdenum in freshwater (RIVM 1997). This MPC represents the safe guideline level for a substance, taking into consideration the most sensitive species and background concentrations in Holland. The MPC used the lowest acute data for invertebrates and fish (96hr EC50 of 29 mg/L for the freshwater annelid Tubifex tubifex (Khangarot 1991)). This value was then divided by a safety factor of 100. The Dutch guidance methodology specifically screens out studies of species from their toxicological dataset that are not found in Holland, and uses a very large safety factor. Thus, the Dutch molybdenum benchmark is not applicable to Canadian waters and appears to be overly conservative.

Australian and New Zealand regulators reported a low reliability trigger value of 0.034 mg/L based on inclusion of all studies of varying quality and applying large safety factors (ANZECC/ARMCANZ 2000). This low reliability trigger for molybdenum does not meet the CCME (2007b) data quality requirements.

The European Union and the United States Environmental Protection Agency (US EPA) have not specified water quality criteria for molybdenum for the protection of aquatic life (European Union 2008; US EPA 2010).

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2.3 PREVIOUS SITE-SPECIFIC WATER QUALITY BENCHMARKS In 2006, SSWQOs for molybdenum based on both acute and chronic exposure scenarios were developed and proposed for use at EKATI (Rescan 2006). The 2006 WQO was derived using only data considered to be relevant in the context of species present at or near EKATI (i.e., either resident aquatic taxa, or suitable surrogate species for residents). An acute HC 5 of 20 mg/L and a chronic HC 5 of 16 mg/L were calculated.

In 2008, the Nevada Division of Environmental Protection derived an acute criterion of 6.16 mg/L for total molybdenum in the State of Nevada and a chronic criterion of 1.65 mg/L (NDEP 2008). In 2009, additional toxicity data were obtained, and an acute criterion of 7.92 mg/L and chronic criterion of 1.90 mg/L were derived (GEI 2009). However, these Nevadaspecific benchmarks are based on warm water species not relevant to the EKATI environment (e.g., bluegill and catfish).

In 2010, nine new chronic toxicity data were reported, along with a Predicted NoEffect Concentration

(PNEC; chronic WQO based on HC 5 value) of 38.2 mg/L (95% confidence limits (CL) of 18.7 to 57.3 mg/L) developed following the European Chemical Agency guidance for derivation of WQO (EC 2006, cited in De Schamphelaere et al. 2010). However, this WQO did not use several studies available in the literature, and was derived specifically in relation to conditions that occur in Holland. Thus it is neither uptodate nor applicable to Canadian waters.

Although the above studies are not specific to EKATI, they provide useful information relevant to the development of SSWQOs for EKATI as described in the next section of this report.

BHP BILLITON CANADA INC. 23 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

3. Methodology

3.1 INTRODUCTION Derivation of the sitespecific water quality objective (SSWQO) for molybdenum followed the most recent guidance from CCME (2003, 2007b). This included guidance for derivation of sitespecific water quality guidelines presented in “Guidance on the SiteSpecific Application of Water Quality Guidelines in Canada: Procedures for Deriving Numerical Water Quality Objectives” (CCME 2003), and updated guidance on deriving water quality guidelines presented in “A Protocol for the Derivation of Water Quality Guidelines for the Protection of Aquatic Life (CCME 2007b).

The main steps for the derivation of the sitespecific WQOs were as follows:

1. Data compilation of existing information including environmental fate, toxicological data, and modifying factors; 2. Identification of relevant toxicological data; 3. Selection of approach to be used in deriving SSWQOs based on available data; and 4. Calculation of objectives and discussion of results and uncertainties.

Prior to deriving the WQO it was necessary to adopt a suitable appropriate approach.

3.2 SITE-SPECIFIC WATER QUALITY OBJECTIVE APPROACHES The CCME (2003) identified four approaches that can be taken to determine SSWQOs for individual substances: 1) the Background Concentration Approach; 2) the Recalculation Approach; 3) the Water Effects Ratio (WER) Approach; and, 4) the Resident Species Approach.

3.2.1 Background Concentration In the Background Concentration Approach, the benchmark is adjusted to reflect background concentrations of the chemical of interest. This approach is generally useful in cases where there are naturallyelevated background concentrations of the parameter of interest.

3.2.2 Recalculation Using the Recalculation Approach, the existing generic benchmark is recalculated after limiting the dataset to available toxicological data for species that are considered relevant to the site (i.e., resident species or suitable surrogates representing taxa for which toxicology data are not available). Species that are not relevant (e.g., tropical species) are excluded from the dataset, in order to create an SSD which represents an appropriate representation of flora and fauna found at site.

3.2.3 Water Effects Ratio Using the Water Effects Ratio (WER) Approach, site and laboratory water are used in parallel toxicity tests to measure the effect that site water has on the toxicity of a substance to laboratory toxicity species. A difference in sensitivity of test organisms between the test waters provides an indication that the site water modifies the toxicity of the substance of interest. This provides justification to alter the water quality benchmark to account for that difference, because WQGs or similar benchmarks are typically derived from toxicity tests conducted in standardized laboratory water. Environmental

BHP BILLITON CANADA INC. 31 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011 and toxicity modifying factors (ETMFs) are characteristics in site water that can alter the behaviour, uptake, or toxicity of a substance to organisms. A weakness of the WER Approach is that it is only applicable to discrete time events, and must be repeated for varying seasons with varying water quality conditions.

3.2.4 Resident Species Using the Resident Species Approach, resident species are tested to evaluate whether they are different in sensitivity from those that have been used to derive the existing benchmark. This approach can account for differences related to tolerance (acclimation and adaptation) to various substances.

3.2.5 Selected Approach for the EKATI SSWQO Calculation The Background Concentration Approach is not applicable to EKATI since background concentrations of molybdenum are generally less than detection limits. The WER Approach is also not applicable as there is little evidence that molybdenum has significant ETMFs that might be present in site water (see Section 4.1.1). Water pH can act as a moderate ETMF when pH is below five, affecting molybdenum speciation and potentially bioavailability, but a low pH (< 5.0) is not relevant to EKATI receiving waters and can itself be toxic. The Resident Species Approach was not necessary because the Recalculation Approach was possible based both on comprehensive aquatic inventory data available for EKATI receiving and nearby waters and the availability of newly published acceptable, relevant toxicity data.

3.3 COMPILATION OF EXISTING INFORMATION

3.3.1 Environmental Fate As part of the initial step in developing the SSWQOs, data on the physical and chemical interactions of molybdenum in aquatic systems were compiled and reviewed. The compilation included a search of primary literature on the environmental fate of molybdenum in aquatic and related systems (i.e ., sediments and soils). The main objectives of this review were to determine:

o primary pathways of molybdenum transport into freshwater ecosystems;

o ultimate environmental fate and partitioning in environmental media such as water and sediments; and

o biological partitioning such as bioaccumulation potential, and natural absorption and excretion routes.

3.3.2 Toxicity Data Both acute and chronic toxicity data from the following sources were used to compile the aquatic toxicity dataset for molybdenum:

o existing water quality guidelines and objectives;

o primary literature; and

o an aquatic toxicity bioassay conducted specifically for this study (Appendix D).

Literature toxicity studies were classified as either primary or secondary relative to the CCME (2007b) criteria for acceptable data. Studies that provided useful information but did not meet the criteria for primary or secondary studies were used as supporting information but were not used directly in the development of the SSWQOs. All other studies were excluded from further consideration. Screening

32 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 METHODOLOGY criteria for inclusion of studies are defined in Section 3.4.1. Supporting studies were also discussed in relation to primary and secondary studies of species, but were not used in the SSD.

3.3.2.1 Existing Water Quality Guidelines Relevant toxicological information on the acute and chronic toxicity of molybdenum contained in the existing CCME, BC MOE, US EPA, Nevada State, and other water quality objectives were summarized.

3.3.2.2 Literature Search The primary literature was searched to ensure that all relevant toxicological data were considered in development of the SSWQOs, with particular focus on studies published subsequent to the ERA of molybdenum commissioned by BHP Billiton (Rescan 2006). Searches included the US EPA Ecotox database, Google Scholar (using the terms “molybdenum”, “molybdate”, “aquatic”, “effect”, “toxic” and/or “toxicity”), Web of Science, and references from review papers.

3.3.2.3 Aquatic Toxicity Bioassay Algae are one of the most sensitive taxonomic groups to molybdenum, but only two chronic studies using plants or algae were available. Therefore, a 72h algal, Pseudokirchneriella subcapitata , growth inhibition bioassay was conducted to supplement the chronic toxicity dataset. Use of this standard bioassay species provided a third plant/alga data point, consistent with the recommendations for optimal number of algal studies contained in CCME (2007b).

The P. subcapitata study (Appendix D) was conducted by Nautilus Environmental (Nautilus) in December 2010, using sodium molybdate with positive and negative controls, and 8 study treatments (measured concentrations: 0, 10.3, 20.3, 40.6, 80, 159, 321, 610 mg/L). Nautilus followed the standard bioassay methodology prescribed by Environment Canada (2007). Treatment concentrations (logbased) were selected to encompass the expected EC 50 based on a previous study on Chlorella sp. (Sakaguchi et al. 1981; 96hr EC 50 of 50 mg/L) and secondary studies with Scenedesmus sp. (Bringmann and Kuhn 1959; Fargosava 1999; HRC 1994, cited in De Schamphelaere et al. 2010) and P. subcapitata (HRC 1994, cited in De Schamphelaere et al. 2010) showing effects thresholds between 3.7 and 54 mg/L. Molybdenum concentrations were measured in the test solutions at test initiation and the measured values were subsequently used to calculate the test endpoints.

3.4 EVALUATION OF RELEVANT TOXICITY DATA Evaluation of the available toxicity data involved three steps. First, each study was screened using the CCME (2007b) criteria to evaluate quality, reliability, accuracy and relevance. Second, the datasets were examined in terms of minimum data requirements for each aquatic biological group. This was completed for acute and chronic data separately. Third, the screened studies within each of the two datasets were further examined and the final SSD for a SSWQO (CCME 2007b) was developed by compiling results for the same endpoints of the same species and removing redundant data from less sensitive test endpoints.

3.4.1 Screening Aquatic Toxicology Studies Once the toxicological dataset was compiled, it was reviewed to determine which studies were acceptable for use in the calculation of the SSD. Criteria used in evaluating the quality of toxicity studies based on CCME (2007b) were:

o use of standard test methodology;

o adequate replication and study design reported;

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o measurement of concentrations of molybdenum in test water treatments (rather than analysis based on nominal concentrations or stock solution concentrations);

o use of sensitive life stages (as appropriate for each species and test);

o reporting whether positive and negative controls were used in the study design, and whether control performance met acceptability criteria for each test;

o reporting of appropriate ranges used for abiotic factors (e.g., water temperature, pH, hardness, dissolved oxygen) as relevant to bioassays and species;

o demonstration of an acceptable concentrationresponse relationship; and

o reporting and use of proper statistical tests in calculating test endpoint(s).

Evaluation of data for inclusion in the guideline derivation separated relevant and acceptable literature data from those that did not meet the minimum CCME selection criteria. Each acute or chronic toxicity study was evaluated based on the eight criteria listed above; results are summarized in an acute dataset (Appendix B) and a chronic dataset (Appendix C). Studies were classified as primary if they at least met the following criteria: reported measurement of concentrations used in study treatments, control response, concentrationresponse shown, ETMF information was provided, study design and replication was reported, and relevant statistics were used. Studies that provided a minimum of ETMF information and control response were classified as secondary data. Other studies provided supporting information (e.g., studies reporting on a second less sensitive endpoint than the most sensitive endpoint for a species) but were not included in the SSD.

Studies were also screened for relevance in the context of species present at the site. A species was classified as resident if it at least belonged to the same genus as a species present at EKATI. Toxicity data on species that are present at EKATI were preferred. However, only a limited number of standardized toxicity tests exist for aquatic species. Therefore, in the absence of data on residents, surrogate species (with standardized toxicity tests) that are taxonomically related to resident taxa or that were found in proximity to EKATI were included to provide the best possible approximation of toxicity to resident species. For important biological groups (e.g., Amphipoda) that did not have corresponding acceptable resident toxicity data, surrogate data at the family level were used. Studies that evaluated taxa that were not resident or surrogate species, or studies that provided little to no toxicological information and failed to meet the above criteria were classified as unacceptable based on CCME (2007b).

Test duration was also screened for all acute and chronic studies using CCME (2007b) guidance. Toxicity tests that were suitable for use in derivation of a shortterm SSWQG were defined as those that met the following criteria (CCME 2007b):

o Fish Test durations of generally 96 hours used in assessing lethality;

o Invertebrates Lethality endpoint from test durations of generally 24 hours to 48 hours for invertebrates, depending on life span, up to 96 hours for longer lived species; and

o Plants/ Algae Lethality test durations of less than 24 hours.

Toxicity tests that were suitable for use in derivation of a longterm SSWQO were defined as those that met the following criteria (CCME 2007b):

o Fish test durations of ≥ 21 days, or ≥ 7 days if involving the egg or larval stages, based preferentially on nonlethal endpoints of growth, egg/larval development, or reproduction;

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o Invertebrates Nonlethal endpoints (growth, reproduction) from test durations of ≥ 96 hours for shorter lived invertebrates or of ≥ 7 days for longer lived invertebrates, and lethal endpoints from tests of ≥ 21 days for longer lived invertebrates (lethal endpoints for < 21 day tests for shorter lived species were considered on a casebycase basis); and

o Plants/ Algae Growth test durations exceeding 24 hours. Plant chronic bioassays were considered on a casebycase basis.

3.4.2 Minimum Requirements for SSD Dataset In order to calculate an acute or a chronic SSD, there are also minimum dataset requirements (CCME 2007b):

o Fish for an acute or a chronic SSD, each require at least three studies on freshwater fish species, including one salmonid and one nonsalmonid;

o Invertebrates for an acute or a chronic SSD, each require at least three studies on freshwater invertebrate species, at least one of which is a planktonic crustacean species; and

o Plants/ Algae for an acute SSD, a plant or alga is desirable but not essential. For a chronic SSD, at least one plant or algal species is required. In the case where plants or algae are among the most sensitive taxa, a chemical is classed as phytotoxic and thereby requires two studies for an acute SSD, or three studies for a chronic SSD.

Although amphibians are known to occur in the Northwest Territories, the EKATI area is beyond their known distribution which is generally below the tree line (ENR 2006, 2012a and 2012b). Thus data on amphibians were not considered or included in the SSD.

Toxicity endpoints derived using sodium molybdate as the test substance were preferred. The vast majority of studies reviewed used this form of molybdenum, and this form predominates in freshwater environments (Cornelis 2005, cited in GEI 2009). Some studies used ammonium molybdate or molybdenum oxides and were listed in the dataset for potential consideration. However, these two substances tend to show higher toxicity than sodium molybdate in tests, likely related to the presence of ammonia and to lower pH as the substances revert to the molybdate form (GEI 2009; De Schamphelaere et al. 2010). Also, ammonia can exert its own toxic effects, particularly in fish (CCME 2007a). Two studies using ammonium molybdate were included in the SSD dataset; these results were used with caution, due to the lack of other suitable studies, and rationale for their inclusion is provided below. Other studies using ammonium molybdate or molybdenum oxide were not used. Regardless of the form of molybdenum source, all endpoints are reported in concentrations of molybdenum.

3.4.3 SSD Data Selection Following the screening of studies for inclusion in the SSD dataset, the complete dataset was examined. Only the most sensitive endpoint from each study was included for each species (e.g., reproduction or growth, not both). For each species, only one data point was included in the SSD.

Acute toxicity test endpoints are typically either the LC 50 , or in rare cases, the Maximum Acceptable Toxicant Concentration (MATC; geometric mean of the NOEC and LOEC). The CCME (2007b) guidance lists a preference ranking for chronic endpoints in the following order:

NoEffects Threshold EC x/IC x > EC 10 /IC 10 > EC 1125 /IC 1125 > MATC > NOEC > LOEC > EC 2649 /IC 2649 > Nonlethal EC 50 /IC 50

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Where two or more of the above endpoints are available for a given species, the preferred endpoint is used. Thus for derivation of a chronic WQO, chronic endpoints including the EC 10 or IC 10 were preferred, followed in order by the MATC, NOEC, EC 11to24 , LOEC, EC 25to49 , and EC 50 . Regressionbased point estimates such as the EC 10 are generally considered to be more appropriate than hypothesis tests, such as the NOEC, LOEC, and MATC values, since results from hypothesis tests can be significantly affected by aspects of study design, such as replication and treatment concentrations (CCME 2007b).

3.5 DERIVATION OF SSWQO The proposed SSWQOs were calculated using the Recalculation Approach to obtain SSDs, consistent with CCME (2007b). Modeling was completed using SSD Master statistical software, developed by Intrinsik Environmental Sciences Inc. (Rodney and Moore 2008). This software package can fit data using a variety of model distributions (normal, logistic, Weibull, Gompertz, and FisherTippett). The best model was selected on the basis of Anderson Darling Goodness of fit tests, as well as best professional judgement based on a visual assessment of the plot to ensure the lower tail of the data distribution was properly modeled, because the lower tail is the most critical area of the SSD for setting benchmarks.

The HC 5 for both acute and chronic data were then determined from their respective SSD distributions for use as SSWQOs. Following derivation of SSWQOs for both acute and chronic exposure scenarios, any data gaps and all uncertainties were reviewed with respect to the SSWQOs and their potential use.

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4. Results

4.1 COMPILATION OF EXISTING INFORMATION

4.1.1 Environmental Fate Molybdenum in freshwater systems originates primarily from the weathering of igneous or sedimentary rock and subsequent runoff into streams or lakes. Other sources include the burning of fossil fuels, use of fertilizers containing molybdenum, and leaching from metal mines. Aerial transport of saltwater aerosols deposited through precipitation can provide a minor source of molybdenum (CCME 1999).

In aquatic environments, molybdenum forms organometallic complexes including molybdate, bimolybdate and molybdenum sulphide. Molybdenum in the molybdate form is considered to be highly bioavailable whereas other forms such as molybdenum disulphide are not readily bioavailable. While molybdate can be readily taken up by biota, most biota are able to readily excrete this substance (Ecometrix 2007). In waters of pH greater than 5, molybdenum is soluble, and at pH greater than 7, the 2 molybdate ion (MoO 4 ) predominates (CCME 1999). At pH less than 5, molybdenum availability and fate in aquatic systems are driven by adsorption, absorption, and coprecipitation of hydroxides of iron and aluminium. Molybdenum is more mobilized in oxic systems compared to anoxic systems in which sulphide complexes can form (Viollier et al. 1995).

Biomagnification refers to increased tissue concentrations of substances from diet up three or more trophic levels. Inorganic substances such as molybdenum do not biomagnify (Chapman 2008). Molybdenum has not been found to biomagnify in aquatic food webs (Saiki et al. 1993).

4.1.2 Acute Toxicity Data A summary of the acute toxicity data gathered from a review of the existing benchmarks and peer reviewed literature is provided in Appendix B. There were a total of 36 acute toxicity studies involving freshwater biota in the literature.

4.1.3 Chronic Toxicity Data A summary of the chronic toxicity data gathered from a review of the existing benchmarks and peer reviewed literature is provided in Appendix C. There were a total of 41 chronic toxicity studies involving freshwater biota in the literature. Results from a bioassay using the green alga, P. subcapitata , are provided in Appendix D. These results were incorporated into the chronic toxicity dataset.

4.1.4 Exposure and Toxicity Modifying Factors (ETMF) A review of existing literature and of benchmarks indicated that there are no major ETMFs for molybdenum toxicity in aquatic systems (CCME 1999; NDEP 2008; GEI 2009; De Schamphelaere et al. 2010). A standard temperature, dissolved oxygen and pH are employed during bioassays and form part of a screening criterion (CCME 2007b).

Water pH affects the speciation and solubility of molybdenum, with molybdenum forming complexes with sulphides below a pH of 5 (Jarrell et al. 1980). At a pH of 7 and greater, molybdenum is mainly in the molybdate form. This form is considered physiologically relevant and 100% bioavailable for uptake into plant and animal cells (Cruywagen 2000). Different molybdenum species show different levels of

BHP BILLITON CANADA INC. 41 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011 toxicity (Sakaguchi 1981). To avoid the confounding effect of pH, studies conducted with laboratory water below pH 6 were not included in the dataset for SSD calculation. This ensured that molybdenum would occur as molybdate. Consequently, the confounding effect of pH on speciation and toxicity was avoided.

Several studies have examined water hardness as an ETMF of molybdenum. Molybdenum toxicity to fathead minnows decreased with increasing water hardness (Tarswell and Henderson 1960). However, Bionomics (1973, cited in NDEP 2008) reported increased toxicity of molybdenum to rainbow trout with increasing water hardness. In that study, acute rainbow trout 96hr LC 50 values were 7,340, 6,790 and 4,950 mg/L in waters with hardness values of 148, 154 and 290 mg/L (as CaCO 3). Other studies found no effect of hardness on molybdenum toxicity (Bentley and Macek 1973; Peterson 1974, cited in Hamilton and Buhl 1997; Hamilton and Buhl 1990; Dwyer et al. 1992; Pyle 2000). Collectively, there is no conclusive evidence that hardness is an ETMF for molybdenum. This conclusion is consistent with the consensus of other researchers in developing molybdenum benchmark values (NDEP 2008; GEI 2009; De Schamphelaere 2010). Hardness was therefore not used in deriving the SSWQOs for EKATI, neither were any other ETMF.

4.2 EVALUATION OF RELEVANT TOXICITY DATA

4.2.1 Acute Data From the available acute toxicity studies, a total of five primary and eight secondary datapoints representing 11 species were included in the SSD: these data represent one protist, seven invertebrates, and three fish species (Table 4.21, Appendix B).

Ten data points in five studies that did not meet all of the CCME (2007b) requirements for primary or secondary studies were classified as supporting information, and were excluded from the SSD data (Appendix B). Studies with rainbow trout, salmon, kokanee, northern pike and fathead minnow reported no effects at the highest treatment concentrations tested, and therefore could not be used to accurately determine an endpoint, but were used as supporting data regarding molybdenum toxicity (Hamilton and Buhl 1990; Pyle 2000; Reid 2002). One study by Diamantino et al. (2000) failed to report control use or response and used nominal concentrations; therefore, it was not used in the SSD. One study was relegated to supporting information status because it did not report control survival or present clear concentrationresponse data, but did provide indications of relative levels of sensitivity (Kimball 1978).

Nine studies were considered unacceptable based on CCME (2007b) and were excluded from the acute SSD dataset (Appendix B). Two of these studies were excluded because they did not use relevant species (Martin and Holdich 1986; Pundir and Saxena 1999, cited in RIVM 2005). The other seven excluded studies did not use or report sufficient information to verify their results (Tarzwell and Henderson 1960, cited in NDEP 2008; Easterday and Miller 1963, cited in GEI 2009; Bionomics 1973, cited in NDEP 2008; Peterson 1974, cited in Hamilton and Buhl 1997; Kimball 1978; Fargasova 1998, cited in RIVM 2005; Borgmann et al. 2005). Rationale for inclusion is provided in Table 4.21 and Appendix B, supported by the discussion for each included species below.

Generally, the more recent studies tended to fulfill all the key requirements for inclusion in an SSD dataset (i.e., they documented a clear concentrationresponse, control responses were reported and were acceptable, test concentrations were measured, and there was a welldefined and acceptable test methodology). Older studies tended to either not use standard methods, did not measure molybdenum concentrations in test solutions (instead relied on nominal concentrations based on stock solution preparation), did not show a concentrationresponse, did not have a sufficient number of

42 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 RESULTS treatments or controls, did not show or report control responses, or otherwise did not provide sufficient information to be considered acceptable per CCME (2007b).

Rationale for inclusion of data is provided in Table 4.21, supported by the discussion for each included species below. Unless otherwise stated, the studies below met all requirements listed by CCME (2007b) for a SSWQO derivation.

Table 4.2-1. Acute Toxicity Studies Used in the Acute Species Sensitivity Distribution

Threshold Value Rationale (Resident = R, Study Class & Species Group Endpoint (mg/L) as Mo Surrogate =S) Reference Euglena gracilis Protist Survival; 679 R Euglena sp. is resident 2 Colmano 24hr MATC 1973 *Chironomus Invertebrates Survival; 7,533 R Chironomus spp. are 1 GEI 2009

tentans (benthic) 48hr LC 50 resident Girardia Invertebrates Survival; 1,226 S Turbellaria are resident 1 GEI 2009

dorotocephala (benthic) 96hr LC 50 Tubifex tubifex Invertebrates Survival; 52.1 R Tubificids are resident 2 Khangarot

(benthic) 48hr LC 50 1991 Crangonyx Invertebrates Survival; 2,650 S Amphipods present in NT 2 Martin and

pseudogracilis (epibenthic) 96hr LC 50 lakes near EKATI Holdich (1986) Ceriodaphnia Invertebrates Survival; 1,015 R Ceriodaphnia spp. are 1 GEI 2009

dubia (planktonic 48hr LC 50 resident crustacean) Daphnia magna Invertebrates Survival; 1,728 R – Daphnia spp. are resident 1 GEI 2009

(planktonic 48hr LC 50 crustacean) Gammarus Invertebrates Survival; 3,940 S Gammarus spp. are found 2 Bionomics

fasciatus (epibenthic 48hr LC 50 in lakes of NT near EKATI 1973; cited in crustacean) NDEP 2008 Catostomus Fish Survival; 1,940 S Longnose suckers are 2 Hamilton

latipinnis (non 96hr LC 50 resident and Buhl 1997 salmonid) Pimephales Fish Survival; 644 S – Lake chub are resident 1 GEI 2009

promelas (non 96hr LC 50 (Cyprinids) salmonid) Oncorhynchus Fish Survival; 5,797 S Round whitefish, Arctic 2 Bionomics

mykiss (salmonid) 96hr LC 50 grayling and lake trout are 1973; cited in resident NDEP 2008 Oncorhynchus Fish Survival; 800 2 McConnell

mykiss (salmonid) 96hr LC 50 1977 Oncorhynchus Fish Survival; 1,320 (1,829.4) 2 McConnell

mykiss (salmonid) 96hr LC 50 1977

Mo = Molybdenum. Note that the text provides full supporting rationale for data inclusion. LC50 is the concentration at which 50% mortality of test organisms is expected MATC is the Maximum Allowable Toxicant Concentration (concentration at threshold for effects; sometimes calculated as the geometric mean of the NOEC and LOEC). Boxed values are from the same species; the geometric mean of these values (shown in parentheses) was used in the SSD. Study class: Numbers before authors in reference column indicate primary study (denoted by 1) and secondary study (denoted by 2). *C. tentans has been renamed C. dilutus.

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Euglena gracilis No acceptable toxicity studies on dominant alga at EKATI (i.e., cyanophytes, chlorophytes, chrysophytes) were available. However a single study on acute toxicity to a unicellular organism – the autotrophic protist Euglena gracillis provided information on sensitivity for this group (Colmano 1973). This 24hr study provided a concentrationresponse relationship, with effects seen at the highest treatment but no effects seen at the other three treatments, and control survival was adequate. There were three shortcomings to this study: 1) measured concentrations were not reported, instead nominal values were used; 2) ammonium dimolybdate was used rather than sodium molybdate; and, 3) the study did not follow a standardized procedure. Use of data from a test using ammonium dimolybdate is not ideal, since ammonia may have contributed to the observed toxicity. However, this study is considered important as it represents the only available acute study for unicellular organisms, and it reflects a conservative estimate of the potential for adverse effects based on the use of ammonium dimolybdate. It was classified as a secondary study. As Euglena spp. are found at EKATI, albeit not in dominant numbers, this species was considered a suitable surrogate and the study was included in the dataset (Appendix B). The geometric mean of the LOEC (960 mg/L molybdenum) and the NOEC (480 mg/L) was calculated as 678.8 mg/L, and this 24hr MATC was used in the acute SSD (Colmano 1973).

Chironomus tentans GEI (2009) conducted replicate bioassays on benthic larvae of the midge, Chironomus tentans (now identified as Chironomus dilutus ). This study was classified as primary because it met all CCME screening requirements. The geometric mean of the 48hr LC 50 values (7,532.0 and 7,534.7 mg/L) was 7,533.3 mg/L. Chironomus spp. are present at EKATI, therefore this study was included in the dataset (Appendix B).

Girardia dorotocephala GEI (2009) conducted replicate bioassays on the turbellarian worm, Girardia dorotocephala . This study was classified as primary because it met all CCME screening requirements. The geometric mean of the

96hr LC 50 values (1,125.8 and 1,334.2 mg/L) was 1,225.6 mg/L. These flatworms are present at EKATI (Appendix B).

Tubifex tubifex Khangarot (1991) conducted an acute bioassay with the oligochaete worm, Tubifex tubifex , and

reported a 48hr LC 50 value of 52.12 mg/L. Nominal values were used instead of measured concentrations; therefore, this work was classified as a secondary study and used in the acute SSD. Standard test methods were used, and reasonably narrow 95% confidence limits (CL) of 42.5 mg/L to 65.6 mg/L were reported, suggesting low control survival, low betweenreplicate variability, and a clear concentrationresponse.

Tubificids are present at EKATI, supporting their inclusion in the acute dataset (Appendix B). Tubificids have been observed in low numbers in lake and stream samples, and generally make up 10% to 15% of oligochaete specimens, which themselves represent generally less than 5% of the benthic invertebrate communities (Rescan 2011a).

Crangonyx pseudogracilis Martin and Holdich (1986) conducted a bioassay with the amphipod, Crangonyx pseudogracilis, and

reported a 96hr LC 50 value of 2,650 mg/L. No control response was reported but controls were used, and the 95% CL (2,516 mg/L to 2,773 mg/L) were narrow indicating good concentrationresponse and low mortality at low treatment concentrations. The study was therefore classified as secondary and

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was included in the acute SSD (Appendix B). A 48hr LC 50 was also reported (3,618 mg/L, 95% CL of 3,481 mg/L to 3,758 mg/L), providing evidence of concentrationresponse over time. This less conservative value was not used for the SSD. Amphipods are present in lakes in the Northwest Territories close to EKATI (Rescan 2011b); therefore, these data were included in the dataset.

Ceriodaphnia dubia GEI (2009) conducted replicate bioassays on the planktonic crustacean zooplankton Ceriodaphnia dubia . This study was classified as primary because it met all CCME screening requirements. The

geometric mean of the 48hr LC 50 values (1,005.5 mg/L and 1,024.6 mg/L) was 1,015.0 mg/L (Appendix B). As C. dubia are found at EKATI, this species endpoint was included in the dataset.

Daphnia magna GEI (2009) conducted replicate bioassays on the planktonic crustacean zooplankton, Daphnia magna .

The resulting geometric mean of the 48hr LC 50 values (1,680.4 mg/L and 1,776.6 mg/L) was 1,727.8 mg/L. Measured concentrations were used, and both control and concentrationresponse reporting were acceptable for this primary study (Appendix B).

Diamantino et al. (2000) reported a 48hr LC 50 of 2,847.5 mg/L (95% CL 2,838 mg/L to 2,857 mg/L) for Daphnia magna (Appendix B). Because no information was provided with regards to control response in this study, it was used only as support for the primary study by GEI (2009) which was used in the acute dataset.

An excluded study with D. magna provided a 48hr LC50 of 3,220 mg/L (Bionomics 1973, cited in NDEP 2008) – indicating lower toxicity than the two previously discussed study. However, the study failed to provide clear reporting of measurement concentrations, abiotic test conditions, and concentrationresponse.

Another excluded study provided a 48hr LC 50 of 206.8 mg/L (Kimball 1978) – indicating higher toxicity. However, this study did not report control survival, was not peerreviewed, and did not show a clear concentrationresponse.

Gammarus fasciatus

The acute 48hr LC 50 for Gammarus fasciatus was 3,940 mg/L (Bionomics 1973, cited in NDEP 2008). NDEP (2008) reported that the study provided sufficient detail to be consistent with standard protocols, reporting of abiotic factors and good control response. However, it was not clear whether measured or nominal concentrations were used, and a clear concentrationresponse relationship was not provided (simply the endpoint was provided). Gammarid shrimp have been found in lakes 60 km to the southwest of EKATI (Rescan 2011b), and this species is considered an appropriate surrogate species for those aquatic invertebrates, thus this secondary study was included in the SSD.

Catostomus latipinnis

The acute 96hr LC 50 for the flannelmouth sucker ( Catostomus latipinnis) was 1,940 mg/L (Hamilton and Buhl 1997). The 95% CL were narrow (1,680 mg/L to 2,340 mg/L) indicating an appropriate concentrationresponse. There was no control mortality. However, nominal concentrations were used in the endpoint calculations, thus this work was considered a secondary study. This species is considered a surrogate for longnose sucker ( Catostomus catostomus ) which is a resident species at EKATI, in the absence of any other data.

A study with white sucker ( Catostomus commersoni ) was excluded because it reported no effects at any treatment concentrations, with a 96hr LC 50 > 2,000 mg/L (Pyle 2000). However, this study provides support for the flannelmouth sucker endpoint and demonstrates that suckers show low sensitivity to molybdenum.

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Other nonsalmonid fish species also show relatively low sensitivity to molybdenum. Northern pike had a 96hr LC 50 > 127.7 mg/L; the study provides supporting information but was excluded for the same reason as listed above for flannelmouth suckers (Pyle 2000). Similarly, the 96hr TL 50 for bluegill (Lepomis macrochirus ) was 6,790 mg/L in another study which was excluded because bluegill are not a relevant species (Bionomics 1973, cited in NDEP 2008). Another excluded study by Easterday and Miller

(1963, cited in GEI 2009) reported a 96hr LC 50 of 1,320 mg/L for bluegill, providing further evidence of low sensitivity of molybdenum in nonsalmonid fish.

Pimephales promelas

The acute 96hr LC 50 for the fathead minnow ( Pimephales promelas) was 644.2 mg/L based on the geometric mean of two replicate tests (609.1 and 681.4 mg/L; GEI 2009). Control response and concentrationresponse were adequate, and measured concentrations were used. The data from this primary study were thus used in the acute SSD. Although this species is not found in the subArctic, preferring warmer and more eutrophic conditions (e.g., muddy pools), it is widely used in toxicity testing, widely distributed through a large portion of Canada, and is a good surrogate for lake chub which are resident at EKATI (both belong to the Cyprinidae family).

Other studies that did not meet primary or secondary study requirements support the above findings.

Pyle (2000) and Kimball (1978) reported 96hr LC 50 values for fathead minnows of >100 mg/L and 628 mg/L, respectively.

Oncorhynchus mykiss

The acute 96hr LC50 for rainbow trout ( Oncorhynchus mykiss) was 800.0 mg/L for 20 mm long fish, and 1,320.0 mg/L for 55 mm long fish (McConnell 1977). Good control and concentrationresponse, but lack of measured concentrations meant that this was classified as a secondary study. Another study

reported a 96hr LC 50 of 5,797.5 mg/L for this species (Bionomics 1973, cited in NDEP 2008). This latter study was also classified as a secondary study because no information was available related to measured concentrations in treatments. The geometric mean of the three test values (1,829.4 mg/L) was conservatively used in the acute SSD dataset.

Studies not included in the acute SSD but supporting the use of the above SSD value included a rainbow trout study that indicated 96hr LC 50 values > 1,000 mg/L for alevin and > 1,190 mg/L for juveniles (Pyle 2000). While no control survival or concentrationresponse were provided since the LC 50 was above the highest treatment concentrations used, these results support the evidence that trout are relatively insensitive to molybdenum. Supporting studies with Pacific salmon species indicated a lack of response at all test concentrations used, also showing low toxicity to salmonids. The 96hr LC 50 for an acute bioassay with kokanee ( Oncorhynchus nerka ) was > 2,000 mg/L, and the 96hr LC 50 values for coho ( Oncorhynchus kisutch ) and chinook salmon (Oncorhynchus tshawytscha ) were both > 1,000 mg/L (Reid 2002; Hamilton and Buhl 1990; Appendix B).

Rainbow trout are distributed widely throughout Canada, although are they not found in the subArctic region or at EKATI. This species is considered a surrogate for round whitefish ( Prosopium cylandriceum) as they are both in the Salmonidae family. Rainbow trout are also related to lake trout ( Salvelinus namaycush) and Arctic grayling ( Thymallus arcticus ). Rainbow trout are the closest available surrogate for these three important salmonid species at EKATI, in the absence of other molybdenum studies.

4.2.1.1 Unacceptable Studies Data for three fish species were excluded from the acute dataset since they were not acceptable surrogate taxa for EKATI fish species: the Ticto barb ( Puntius ticto) (Pundir and Saxena 1990, cited in RIVM 2005); the channel catfish ( Ictalurus punctatus ) (Bionomics 1973, cited in NDEP 2008); and the

46 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 RESULTS bluegill ( Lepomis macrochirus ) (Easterday and Miller 1963 and Bionomics 1973, cited in NDEP 2008). These warm water species are considered unsuitable as surrogates for any fish species found at EKATI.

Some studies with relevant species were excluded because the study failed to report or meet critical requirements for studies to be used in deriving a SSWQO (CCME 2007b). A study of acute toxicity to the amphipod Hyallela azteca (Borgmann et al. 2005) reported a 7d LC 50 >1.0 mg/L. However, it used very low test concentrations and no adverse effects were seen in any treatment. This study and species were therefore excluded from the dataset; however, the results do indicate that shortterm acute toxicity to amphipods would be expected to be greater than 1 mg/L.

Fargasova (1998, cited in RIVM 2005) reported acute toxicity results for the midge Chironomus plumosus (96hr LC 50 of 0.46 mg/L) and the oligochaete Tubifex tubifex (96hr EC 50 of 4.6 mg/L). However, these results were excluded from the acute dataset because nonstandard methods were used, no measured concentrations were reported, no test conditions were available, and no control response or concentrationresponse were provided.

Two studies with fathead minnows were excluded. The first study did not show a clear concentration response, did not report measured concentrations, and reported a 96hr LC50 of 7,630 mg/L which was over 10 times higher than all other studies for this species (Bionomics 1973; cited in NDEP 2008). The second fathead minnow study provided a 96hr LC 50 of 70mg/L for water hardness of 20 mg/L as CaCO 3 (Tarzwell and Henderson 1960, cited in NDEP 2008). However, there was insufficient information provided in this study with which to assess the validity and relevance of results in terms of test methods, controls and concentrationresponse.

4.2.1.2 CCME Acute Dataset Requirements The 13 acceptable acute toxicity tests included 11 species (Table 4.21: one protist, seven invertebrate and three fish species). Therefore, CCME (2007b) requirements for groups of different biota that must be included in the SSD were met. Benthic and planktonic invertebrates and fish are wellrepresented by the available dataset. All of the available acute data on fish indicate relatively low sensitivity to molybdenum. Algae are not well represented in this acute dataset. This is partly due to the fact that most algae bioassays are considered to be chronic in nature; it is difficult to assess shortterm lethality to this class of aquatic life.

4.2.2 Chronic Data The available chronic toxicity data on molybdenum were summarized and screened for inclusion in the SSD (Table 4.22, Appendix C). A total of 15 primary tests were included, including data from 10 genera (one plant, one alga, six invertebrates, and two fish). The majority of the included data come from recent studies by GEI (2009) and De Schamphelaere et al. (2010). As with the acute studies, many chronic studies failed to provide sufficient information or failed to meet all CCME (2007b) requirements related to measured test concentrations, concentrationresponse, control response, experimental design, and statistical methods.

Ten chronic endpoints from secondary studies which did not meet all of the requirements required for inclusion in the SSD dataset were also tabulated (Appendix C). These studies on relevant genera were used as supporting information. Four of the studies provide secondary information on sensitivity of algae to molybdenum. Studies by Huntington Research Council (HRC 1994) could not be obtained but were reported in De Schamphelaere et al. (2010).

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Table 4.2-2. Chronic Toxicity Studies Used in Deriving a Long-term Water Quality Objective

Species Chronic Value Rationale (Resident = Study Class & (common name) Group Endpoint (mg/L) as Mo R, Surrogate = S) Reference Lemna minor Plant Growth; 241.5 S – Macrophytes are 1 De

(Duckweed) 7d EC 10 present at EKATI Schamphelaere et al. 2010 Chlorella regularis Alga Growth; 50 S – Green algae genera 2 Sakaguchi et

(Green algae) 96hr EC 50 are present at EKATI al. 1981 Pseudokirchneriella Alga Growth; 25.1 S – Green algae genera 1 This report,

subcapitata 72hr EC 10 are present at EKATI Appendix D (Green algae) Brachionus calyciflorus Invertebrates Population 193.6 S – Rotifers are present 1 De (Rotifer) (pelagic) Growth; at EKATI Schamphelaere et

48hr EC 10 al. 2010 Lymnaea stagnalis Invertebrates Growth; 211.3 S Molluscs are present 1 De

(Snail) (benthic) 28d EC 10 at EKATI Schamphelaere et al. 2010 Chironomus riparius Invertebrates Growth; 121.4 R Chironomus spp. are 1 De (midge) (benthic) 14d EC10 resident Schamphelaere et al. 2010 Ceriodaphnia dubia Invertebrates Reproduction; 34.0 R Ceriodaphnia spp. 1 Naddy et al.

(spiny waterflea) (planktonic 8d IC 12.5 are resident 1995 crustacean) Reproduction; 78.2 1 De

7d EC 10 Schamphelaere et al. 2010 Reproduction; 50.8 (51.3) 1 GEI 2009

6d EC 10 Daphnia magna Invertebrates Reproduction; 61.2 R Daphnia spp. are 2 Diamantino et (waterflea) (planktonic 21d MATC resident al. 2000 crustacean) Reproduction; 105.6 1 De

21d EC 10 Schamphelaere et al. 2010 Reproduction; 107.9 (88.7) GEI 2009

21d EC 10 Pimephales promelas Fish (non Growth; 39.3 S – Lake chub are 1 De

(fathead minnow) salmonid) 34d EC 10 resident (cyprinids) Schamphelaere et al. 2010 Growth; 90.9 (59.8) GEI 2009

28d EC 10 Oncorhynchus mykiss Fish Growth; 43.2 S Round whitefish, 1 De

(rainbow trout) (salmonid) 7d EC 10 Arctic grayling and lake Schamphelaere et trout are resident al. 2010 (salmonids)

Mo = Molybdenum. Note that the text provides full supporting rationale for data inclusion. Boxed values are from the same species; the geometric mean of these values (shown in parentheses) was used in the SSD.

ICx (e.g., IC 20 ) is the concentration at which x% of test organisms are expected to be inhibited (e.g., inhibited reproduction).

ECx (e.g., EC 10 ) is the concentration at which x% of test organisms are expected to show an effect. MATC is the Maximum Allowable Toxicant Concentration (concentration at threshold for effects, sometimes calculated as the geometric mean of the NOEC and LOEC. Study class: Numbers before authors in reference column indicate primary study (denoted by 1) and secondary study (denoted by 2).

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Three invertebrate studies on the survival endpoint were excluded since the reproduction endpoint was selected for these invertebrates ( D. magna and C. dubia ). Finally, three fish studies were listed as secondary studies. The rainbow trout survival endpoint of Davies et al. (2005) was not used in the SSD since growth was shown to be a more sensitive endpoint. Pyle (2000) reported no effects at the highest treatment concentrations for fathead minnows; thus, there was no concentrationresponse and an effects benchmark could not be determined.

Rationale for inclusion of data is provided in Table 4.22, supported by the discussion for each included species below. Unless otherwise stated, the studies below met all requirements listed by CCME (2007b).

Lemna minor

A primary study examining molybdenum toxicity to lesser duckweed, Lemna minor , reported a 7d EC 10 of 241.5 mg/L (95% CL of 183.6 mg/L to 317.7 mg/L) for frond growth (De Schamphelaere et al. 2010). L. minor is a macrophyte that is widely used in toxicity testing, and provides a suitable surrogate for aquatic grasses and other macrophytes that are present at EKATI (Appendix C).

Chlorella regularis

The green alga Chlorella regularis was exposed to ammonium dimolybdate, resulting in a 96hr EC 50 of 50 mg/L based on growth (Sakaguchi et al. 1981). While there are limitations to this secondary study, including limited reporting of methods and abiotic factors, potential confounding factor of ammonia effects (i.e., a conservative result), and use of nominal concentrations, it is of value since it provides a valid endpoint and reports good control survival. Green algae are present at EKATI; therefore, this secondary study was included in the chronic dataset (Appendix C).

In support of including Sakaguchi et al. (1981) in the chronic SSD, a study by Bringmann and Kuhn (1959) reported a 96hr chronic threshold of 54 mg/L. However, the experimental design did not describe the treatments concentrations used, whether controls were used, whether molybdenum was measured or reported nominally, or how the chronic endpoint was calculated. In addition, the study used ammonium dimolybdate; therefore, ammonia toxicity could have been a confounding factor in this bioassay. While this conservative benchmark has been used to set a chronic guideline by the Dutch Institute for the Environment (RIVM 1997), it is provided here only as a supporting study for algae confirming that they are relatively sensitive to molybdenum. This study was also cited by McKee and Wolf (1963), who included it in the dataset used to develop the WQG for molybdenum in British Columbia (Swain 1986).

A chronic study with the green alga Scenedesmus quadricauda reported a 12d EC 50 of 3.71 mg/L based on reduced production of new cells as a measure of growth (Fargasova 1999, cited in RIVM 2005). There was insufficient information to verify the reliability of this study in terms of standard methods used, control response, measured concentrations of test solutions, and concentrationresponse. Also, it used ammonium dimolybdate instead of sodium molybdate; therefore, ammonia toxicity could have been a confounding variable in this experiment. Thus, the results of this work are relegated to supporting information highlighting the potential phytotoxicity of molybdenum in freshwater aquatic environments.

Another chronic study reported a 72hr NOEC of 12.5 mg/L with Scenedesmus subspicatus and a 72hr NOEC of 4.6 mg/L with Pseudokirchneriella subcapitata (HRC 1994, cited in De Schamphelaere et al. 2010). These studies were deemed unreliable by De Schamphelaere et al. (2010) for inclusion in regulatory risk assessments in Europe, according to EU Regulation No 1907/2006 (EC 2006). The studies did not show a reliable concentrationresponse and failed to report measured test concentrations.

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Regardless, these studies provide supporting evidence that algae are particularly sensitive to molybdenum and supported the results of the P. subcapitata bioassay (Appendix D).

Pseudokirchneriella subcapitata The green alga P. subcapitata (formerly Selenastrum capricornutum ) has been widely used in toxicity bioassays and green algae are present at EKATI. A chronic bioassay with P. subcaptitata was conducted by Nautilus in December 2010 (Appendix D). It used sodium dimolybdate and resulted in a 72hr EC 10 of 25.1 mg/L based on growth. This value is lower than the endpoint for Chlorella regularis (see above) but higher than the supporting information on Scenedesmus subspicatus and P. subcapitata (HRC 1994, cited in De Schamphelaere et al. 2010). The Nautilus bioassay followed standard testing protocols and met all CCME (2007b) screening requirements. This primary study was included in the chronic SSD.

Brachionus calyciflorus

The planktonic rotifer B. calyciflorus was used in a chronic study resulting in a 48hr EC 10 of 193.6 mg/L (95% CL of 50 mg/L to 756 mg/L) based on population growth rates (De Schamphelaere et al. 2010). While the confidence limits are large, the study met all screening requirements for a primary study. This rotifer is often used in bioassays and serves as a suitable surrogate for rotifers resident in lakes of EKATI (Appendix C).

Lymnaea stagnalis

The snail L. stagnalis was used in a chronic study resulting in a 28d EC10 of 211.3 (95% CL of 173 mg/L to 283 mg/L) based on growth (De Schamphelaere et al. 2010). This species serves as a suitable surrogate for molluscs that are resident at EKATI (Appendix C). This primary study was included in the dataset.

Chironomus riparius

The midge C. riparius was used in a chronic study resulting in a 14d EC10 of 121.4 (95% CL of 61 mg/L to 242 mg/L) based on biomass as a measure of growth (De Schamphelaere et al. 2010). This species is amenable to bioassay testing and serves as a suitable surrogate for chironomids (including resident Chironomus spp.) and several other dipteran benthic insects that are resident at EKATI (Appendix C). This study was classed as primary and included in the chronic dataset.

Ceriodaphnia dubia Three primary reproduction studies using the spiny waterflea, C. dubia , were reported for molybdenum. This planktonic crustacean is widely used in toxicity tests, and is a resident at EKATI.

Naddy et al. (1995) report an 8d IC 12.5 of 34 mg/L and an 8d IC 25 of 47 mg/L. De Schamphelaere et al. (2010) reported a 7d EC 10 of 78.2 mg/L (95% CL of 50 mg/L to 123 mg/L) based on reproductive effects, and a 7d MATC of 231.2 mg/L based on survival. GEI (2009) reported a 6d EC 10 of 50.8 mg/L for reproduction, calculated as the geometric mean of two replicate EC 10 values (45.6 mg/L and 56.5 mg/L). GEI (2009) reported a 6d LC 10 of 187.9 mg/L. The reproduction endpoint was selected because it was the most sensitive. The geometric mean of the three reproduction endpoint values (34 mg/L, 50.8 mg/L and 78.2 mg/L) was 51.3 mg/L, and this was included in the chronic SSD dataset (Appendix C).

Daphnia magna The waterflea, D. magna, was used in three chronic toxicity studies with molybdenum. A 21d MATC of 61.2 mg/L based on reproduction was calculated as the geometric mean of the NOEC (50 mg/L) and the LOEC (75 mg/L) (Diamantino et al. 2000). This study also reported a 21d MATC of 61.2 mg/L for growth and 86.8 mg/L for survival. This study was classified as secondary due only to the lack of measured

410 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 RESULTS concentrations as all other test acceptability criteria were met. De Schamphelaere et al. (2010) reported a 21d EC 10 of 105.6 mg/L (95% CL of 92 mg/L to 122 mg/L) based on reproductive effects. GEI (2009) reported 21d EC 10 values of 107.9 mg/L for reproduction and 200 mg/L for adult survival. The reproductive endpoint was selected as it was the most sensitive. The latter two studies met all acceptability criteria and were classified as primary; the Diamantino et al. (2000) secondary study was also included to provide a measure of conservatism as its benchmark was lower. The geometric mean of the three reproductive endpoint values (61.2 mg/L, 105.6 mg/L, and 107.9 mg/L) was 88.7 mg/L for inclusion in the chronic SSD.

Pimephales promelas The fathead minnow Pimephales promelas was used in two chronic toxicity studies with molybdenum. While fathead minnows are not found in the subArctic, they are widely distributed in most of Canada, are used in toxicity tests in Canada, and are taxonomically related to lake chub (both are cyprinids), which are resident at EKATI. Therefore, fathead minnows were included in the chronic SSD dataset as a

surrogate fish species for lake chub. De Schamphelaere et al. (2010) reported a 34d EC 10 of 39.3 mg/L (95% CL of 32.7 mg/L to 52.6 mg/L) for growth based on dry weight. GEI (2009) reported a 28d EC 10 of 90.9 mg/L for the same endpoint, based on the geometric average of two replicate tests (83.2 mg/L and 99.2 mg/L). Both studies met requirements for primary study classification (Appendix C). The geometric mean of the two study values, 59.8 mg/L, was included in the SSD.

A study by Pyle (2000) provided supporting information for the above studies suggesting that the endpoint used in the SSD was conservative, but since no effects were seen at the highest test concentrations, this study was not included in the chronic SSD. Pyle (2000) reported a 3d LOEC of >100 mg/L for both egg survival and timetohatch endpoints, and a 7d LOEC of > 100 mg/L for growth.

Oncorhynchus mykiss Rainbow trout (Oncorhynchus mykiss ) embryos were used in chronic toxicity tests with molybdenum. A 32d MATC of 866 mg/L based on survival was calculated as the geometric mean of the NOEC

(750 mg/L) and the LOEC (1,000 mg/L) (Davies et al. 2005). These authors also reported a 32d LC 20 of 1,425 mg/L, but no LC 50 could be calculated due to insufficient mortality. De Schamphelaere et al. (2010) reported a 7d EC 10 of 43.2 mg/L (95% CL of 19.7 mg/L to 94.7 mg/L) based on biomass as a measure of growth. Based on guidance for deriving a SSWQO (CCME 2007b), only the most sensitive endpoint (growth) was used for this species. The Davies et al. (2005) data based on survival were used as supporting information, and the value of 43.2 mg/L for growth was used to represent O. mykiss in the chronic dataset (Appendix C).

4.2.2.1 Chronic Toxicity Testing 2010 The 72h growth inhibition bioassay using the green algae, Pseudokirchneriella subcapitata , indicated a

chronic IC 25 of 25.1 mg/L (Appendix D) with 95% CL of 0.4 to 30.9 mg/L. The results of the growth inhibition bioassay also indicated that the chronic IC 50 was 86.5 mg/L with 95% CL of 9.7 mg/L to 130.1 mg/L. A reliable IC 10 value could not be determined due to data variability. Therefore, the IC 25 of 25.1 mg/L was included in the chronic dataset.

This study used standard test methods, and reported good control survival, abiotic test conditions, measured concentrations of test solutions, and demonstrated a clear concentrationresponse relationship. This study serves as a critical chronic toxicity endpoint for the chronic SSD, because this

IC 25 is the lowest value (most sensitive) in the chronic dataset. There are few toxicological data on molybdenum effects to algae, which appear to be among the most sensitive biota (see also the discussion in the Chlorella regularis section above).

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4.2.2.2 Unacceptable Studies Fifteen reported toxicity endpoints were excluded from use in the chronic SSD (Appendix C). One of the studies (McKee and Wolf 1963) reported information previously reported elsewhere (Bringmann and Kuhn 1959) and thus was not a separate study.

Kimball (1978) reported a 28d LC 50 of 0.93 mg/L and a 28d MATC of 0.88 mg/L based on the NOEC and LOEC for reproductive inhibition in D. magna . The study used standard methodology, and adequate control survival, measured concentrations of test solutions, and good concentrationresponse. The author used molybdenum oxide as a molybdenum source; this may not have been a confounding factor in developing the acute SSD, as most molybdenum would have been in molybdate form at the pH of 7 used during the test, similar to other studies. However, the effects levels reported were 70 to 123 times lower than all other results for D. magna , and well over 10 times lower for other biota (Kimball 1978). Therefore, this study was suspect and, based on methodology for outlier data prescribed by US EPA (Stephan et al. 1985), it was excluded from the chronic dataset.

Four reported endpoint values were excluded from the chronic SSD because they did not represent suitable species. These studies involved bioassays using the African clawed frog (De Schamphelaere et al. 2010), the goldfish (Birge 1978), and the narrowmouthed toad (Birge et al. 1978). Although amphibians are known to occur in the Northwest Territories, the EKATI area is beyond their known distribution which is generally below the tree line (ENR 2006, 2012a and 2012b). Thus the frog and toad studies were not relevant for deriving a SSWQO for EKATI. The goldfish is an Asian minnow species that is widely introduced throughout North America; fathead minnows were considered more relevant as a surrogate for lake chub, which reside at EKATI.

Four endpoints involved very low treatment ranges, and failed to show effects at the highest treatment concentration; these were not used because an effects threshold was not determined. A chronic study reported a 13d IC 25 of >1.7 mg/L based on growth of northern pike, and a 22d LC 50 of >1.7 mg/L in white suckers (Pyle 2000). A chronic bioassay using rainbow trout yielded a 1yr LOEC of >17 mg/L

(McConnell 1977). Another rainbow trout study reported an 18month EC 20 of >18.5 mg/L (Goettl and Davies 1976).

Finally, the four Birge (1978) and Birge et al. (1980) endpoints were not included since they used non standardized methods that resulted in much different endpoints than those produced from standardized testing as shown in Davies et al. (2005; cf Section 2.2). These toxicity studies are considered unreliable since toxicity data for all other studies showed effects at two to three orders of magnitude higher concentrations (Goettl and Davies 1976; McConnell 1977; NDEP 2008; De Schamphelaere et al. 2010). Three studies (Ennevor 1993; McDevitt et al. 1999; Pickard et al. 1999, all cited in Davies 2005) provide further evidence that the studies by Birge (1978, 1980) are unreliable. For more details, see Section 2.2.

4.2.2.3 CCME Chronic Dataset Requirements The 15 chronic toxicity studies included 10 species (one plant, two algae, five invertebrates and two fish species). The minimum data requirements of three algae/plants and three invertebrates (including a planktonic crustacean) were met. The chronic dataset provides better coverage of plants and algae than was possible for the acute SSWQO, based on available studies. Both benthic and planktonic invertebrates are wellrepresented by the available chronic dataset.

However, only data for two of the CCME (2007b) recommended three fish species (representing both salmonid and nonsalmonid species) were available. Of the eight major fish species at EKATI, five are represented by surrogates (Table 4.2.2 and discussion above: lake trout, round whitefish, Arctic grayling, and lake chub). There were no suitable surrogates for burbot , slimy sculpin , or ninespine

412 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 RESULTS stickleback , based on the available chronic studies. Sticklebacks are extremely rare in the study area, and burbot are also rare (Rescan 2008). However, in contrast, slimy sculpin represent a significant proportion of the fish community in EKATI lakes and streams. Lack of toxicological data on sculpins is a limitation of the current study but is not considered critical as algae are the most sensitive species and

the final derived HC 5 was below the most sensitive data available for algae (see Section 4.3.2).

Wheeler et al. (2002) suggest a minimum of 10 datapoints be used in estimating an HC 5. The US EPA uses a minimum of eight datapoints in such calculations (Posthuma et al. 2002). Newman et al. (2000) suggest 15 to 55 datapoints. CCME (2007b) does not have a minimum requirement for the number of data in an SSD. The use of 10 datapoints in deriving the HC 5 for molybdenum in this report is above US EPA requirements for conducting SSD calculations.

4.3 DERIVATION OF SSWQO Following the screening of the available studies and addition of new data from the algal bioassay

(P. subcapitata ), shortterm and longterm SSWQOs were calculated based on HC5 values for each of the two SSDs.

4.3.1 Acute SSD An acute toxicity data SSD was developed using the 11 acute data points. A nonlinear regression was used to model the data, based on the Gompertz model (Figure 4.31; Appendix E). Data were tested for goodnessoffit using the AndersonDarling test (A2 = 0.329; critical value = 1.93 for α = 0.10) and visual assessment of the lower tail of the SSD plot. The Gompertz model fit the data most closely, particularly in association with the lowest ( T. tubifex ) chronic data point (52 mg/L).

Other distributions were tested, including normal, logistic, Weibull, and FisherTippett, but these distributions did not fit the data as closely as Gompertz which provided the lowest (most conservative)

HC 5 (223 mg/L; see below). Model plots and AndersonDarling test coefficients are provided in Appendix E. The Weibull distribution showed a similar pattern to the Gompertz model but did not fit the data as well (A2 = 0.440) and was slightly less predictive in the lower tail of the SSD. While the logistic model showed a slightly better fit to the acute molybdenum data set as a whole (A2 = 0.351), it did not fit the lower tail of the distribution as well as the Gompertz model. The same was true for the normal distribution (A2 = 0.676). The FisherTippett model failed to adequately fit the data (A2 = 4.786; critical value = 1.93) and also exhibited the worst fit to the lower tail.

A shortterm SSWQO was calculated from the acute SSD by estimation of the 5 th percentile of this

distribution, referred to as the acute HC 5. The acute HC 5 calculated on this basis was 222.7 mg/L (95% CL of 109.9 mg/L to 451.4 mg/L). The equation of the Gompertz fitted model is:

y = 1 e –[e (x3.307)/( 0.32)] where y is the proportion of taxa affected, and x is the molybdenum concentration (mg/L).

This new shortterm HC 5 is much higher than the previous acute SSWQO (20 mg/L) calculated by Rescan (2006) because several new studies were made available, and three of the most sensitive species previously included in the guideline derivation were removed based on CCME (2007b) criteria and review. Two of the previously included species ( Chlorella and Scenedesmus ) were not included in the current acute SSWQO because they were considered chronic exposures (96hr) rather than acute (< 24 hr) exposures (CCME 2007b). In addition, the previously included Anabaena sp. was not used in the derivation of the current acute SSWQO because it represented nutrient deficiency rather than toxic response through overdose (Steeg et al. 1986). Removal of these three lower endpoints from the SSD had a strong effect on the lower tail of the distribution and resultant HC 5. The updated 2011 shortterm HC 5 is based on the most recent acceptable data in the literature using CCME (2007b) methodology.

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1.0 Chironomus tentans

Gompertz Model Gammarus fasciatus Confidence Limits 0.8 Fish Invertebrate Crangonyx pseudogracilis Phototrophic Protist Catostomus latipinnis x-3.307 -[e( 0.32 )] 0.6 y = 1-e Oncorhynchus mykiss

Daphnia magna

0.4 Girardia dorotocephala

Ceriodaphnia dubia

Euglena gracilis

Proportion of Taxa Affected 0.2 HC5 = 223 mg/L Pimephales promelas Tubifex tubifex

0.0 1 10 100 1,000 10,000 100,000 Total Molybdenum (mg/L)

Figure 4.3-1 Acute Species Sensitivity Distribution for Molybdenum at EKATI RESULTS

One of the acute species (T. tubifex ) endpoints is 52 mg/L, which is well below the calculated HC 5 of 223 mg/L. This result indicates that oligochaetes could exhibit adverse effects under short term exposure scenarios at levels below the recommended shortterm SSWQO even though the longterm SSWQO (Section 4.3.2) is much lower than the acute SSWQO. However, two factors suggest that this result will not adversely affect the benthic communities of waters downstream of EKATI. First, tubificids make up a small proportion (generally less than 5%) of the benthic community at EKATI in terms of density and richness, and therefore any impacts to this group would not be expected to have major trophic or ecological consequences (Rescan 2011a). Second, this result is based on exposures in water without sediment. Tubificid oligochaetes live and burrow into muddy sediments, which lifestyle minimizes their exposure to shortterm changes in overlying water quality (Chapman et al. 1982a, b; Chapman and Brinkhurst 1981, 1984).

4.3.2 Chronic Species Sensitivity Distribution A chronic toxicity SSD was developed using the 10 chronic data points. A nonlinear regression was completed on the data using the normal model (Figure 4.32; Appendix F). This fit was assessed using both the AndersonDarling goodnessoffit test test (A 2 = 0.291; critical value = 1.93 for α = 0.10) and visual assessment of the lower tail of the SSD plot, because this is the critical region in developing a SSWQO.

Other model distributions were tested, including Gompertz, logistic, Weibull, and FisherTippett (Appendix F). The Gompertz model overestimated toxicity with a lower tail far to the left of the data and did not fit the data as well as the normal distribution (A2 = 0.291). The Weibull (A2 = 0.317) and logistic (A2 = 0.309) distributions provided slightly weaker fit to the data compared to the normal model; the former two models also slightly overestimated toxicity in the lower tail. While the Fisher Tippett model provided slightly better overall fit (A2 = 0.269) compared to the normal model, the FisherTippett model slightly underestimated toxicity. The normal distribution provided the best

estimation of the HC 5 based on a combination of statistical assessment (better AndersonDarling coefficient than logistic, Weibull or Gompertz), conservatism (more conservative than FisherTippett) and visual assessment of the lower tails of the SSD.

The equation of the Normal fitted model is:

y = ½ {1 + erf [(x1.917)/ (0.383*√2)] }

where y is the proportion of taxa affected, x is the molybdenum concentration (mg/L), and erf is the Gauss error function of the cumulative normal distribution.

A longterm SSWQO was calculated from the chronic SSD by estimation of the chronic HC 5. The chronic HC 5 calculated on this basis was 19.38 mg/L (95% CL of 13.63 to 27.55 mg/L).

This new HC 5 value is greater than the chronic SSWQO value (16 mg/L) reported in Rescan (2006), because of the inclusion of additional data on both previously listed species and also six new species (C. dubia , C. riparius , P. pimelas , B. calyciflorus , L. stagnalis , and L. minor ). Endpoints of some species previously listed in the SSWQO derived by Rescan (2006) were not included because: 1) Anabaena sp. reflected nutrient deficiency effects rather than overdose effects (Steeg et al. 1986); 2) Esox lucius chronic endpoints did not show any effect at the highest treatment concentration (Pyle 2000); and, 3) the Catostomus latipinnus chronic value was estimated, not measured (Rescan 2006), and thus was highly uncertain.

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1.0

Normal Model Lemna minor 95% Confidence Limits Fish Invertebrate Lymnaea stagnalis Alga/Plant 0.8 y = ½ 1 + erf (x-1.917) { [ (0.383 2) ]} Brachionus calyciflorus

Chironomus riparius 0.6 Daphnia magna

Pimephales promelas 0.4 Ceriodaphnia dubia Proportion of Taxa Affected

Chlorella regularis 0.2

HC5 = 19 mg/L Oncorhynchus mykiss

Pseudokirchneriella subcapitata 0.0 1 10 100 1,000 10,000 Total Molybdenum (mg/L)

Figure 4.3-2 Chronic Species Sensitivity Distribution for Molybdenum at EKATI RESULTS

The newly derived chronic HC 5 is less than each of the chronic data points included, indicating that it is likely protective of all groups of biota at EKATI (algae, plants, invertebrates, and fish). The current chronic HC 5 of 19.38 mg/L falls between the chronic benchmark developed by NDEP (2008) of 1.65 mg/L, the GEI (2009) chronic benchmark of 2.44 mg/L, and the higher chronic HC 5 value of De Schamphelaere et al. (2010) of 38.2 mg/L. Differences are related to the inclusion of more data, and screening of genera relevant to the EKATI environment.

The recommended longterm SSWQO for EKATI is intended to be used in routine monitoring of the downstream receiving environment based on continuous exposure to molybdenum. This new SSWQO is based on updated CCME methodology, uses toxicological data specific to the EKATI biological community, incorporates more recent studies not available in 1999 when the CCME WQG was developed, and is therefore considered appropriate and scientifically defensible for use at EKATI.

BHP BILLITON CANADA INC. 417 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

5. Uncertainty

5.1 INTRODUCTION The derivation of a SSWQO involves multiple steps (CCME 2003, 2007b). Uncertainties inherent in this process can be present in numerous areas, including the accuracy of toxicity endpoints in available studies, the availability of a sufficient number of toxicity studies on all relevant biological groups at a site, the understanding of chemical fate, and the extrapolation process in estimation of a benchmark value.

The uncertainties and assumptions used in deriving the SSWQOs for EKATI included: 1) relevance of the toxicological datasets; 2) bioavailability; 3) tolerance; and 4) toxicity of mixtures. Some of these uncertainties have been mentioned in other sections of this report. They are more fully described below.

5.2 RELEVANCE OF THE TOXICOLOGICAL DATASETS The uncertainties and limitations of the datasets and SSD approach are discussed in the following sections. The datasets used and extrapolation involved in the SSD process are associated with the largest potential sources of uncertainty. This is because the extrapolation work is central to the derivation of the SSWQOs, and can be greatly affected by the selected data points used for SSWQO derivation.

5.2.1 Inclusion Criteria Only primary and secondary data were included in the acute and chronic datasets, based on CCME (2007b) guidance. Other studies were used only in discussions to support these data, and were not included in the SSDs.

Acute Data Of the 13 studies used in the acute SSD, five were classified as primary studies and eight were classified as secondary studies (CCME 2007b; Table 4.21; Appendix B). The species associated with use of secondary studies are discussed below in regards to CCME (2007b) inclusion criteria:

o Euglena gracilis : This study by Colmano (1973) is cited also in NDEP (2008) and met the CCME (2007b) screening criteria except that nominal values were used, and study treatments were fewer than standard. It provided the only data on unicellular autotrophic biota (similar to algae) for the acute dataset.

o Tubifex tubifex : This study by Khangarot (1991) provided the only acute endpoint for the oligochaete group, and is widely cited by others (including RIVM 1997; NDEP 2008; GEI 2009). The study by Khangarot (1991) met all of the CCME (2007b) screening criteria except that nominal values were used. It also provided the lowest acute endpoint and thus greatly influenced the lower tail of the SSD.

o Crangonyx pseudogracilis : Martin and Holdich (1986) provided an acute endpoint and used

controls but did not directly report control survival. The resulting LC 50 with narrow 95% confidence limits lends support to the use of this secondary study, suggesting that control survival was acceptable (i.e., high).

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o Gammarus fasciatus : This secondary study (Bionomics 1973, cited in NDEP 2008) met all requirements of the CCME (2007b) guidance except that it was not clear whether nominal or measured concentrations were used in calculations. It was relatively insensitive compared to other genera and therefore would not be expected to have greatly affected the lower tail of the SSD.

o Catostomus latipinnis : This secondary study (Hamilton and Buhl 1997) met all requirements of the CCME (2007b) guidance except that it used nominal concentrations in calculations. It provided a valuable third acute data point for the fish group, and represented longnose suckers which reside at EKATI. It was relatively insensitive compared to other genera and therefore would not be expected to have greatly affected the lower tail of the SSD.

o Oncorhynchus mykiss : Three data points for this species were provided from studies by McConnell (1977) and Bionomics (1973, cited in NDEP 2008). These studies met all CCME requirements except that nominal concentrations were used instead of measured concentrations. These studies are supported by other fish bioassays indicating that fish are not acutely sensitive to molybdenum.

Chronic Data Thirteen of the 15 chronic data points were obtained from primary studies based on screening with CCME (2007b) criteria. Two secondary data points were also included, and are discussed below:

o Chlorella regularis : This secondary study (Sakaguchi et al. 1981) met all requirements of the CCME (2007b) guidance except that it used nominal concentrations in calculations. It provides a third alga/plant chronic data point.

o Daphnia magna : A 21d MATC was reported by Diamantino et al. (2000) in a secondary study that used nominal concentrations. This value was slightly lower than results of two primary studies (GEI 2009; De Schamphelaere et al. 2010); it was conservatively incorporated into the higher other two values to produce the single value used in the chronic SSD.

5.2.2 Duration Criteria All toxicological data were categorized by exposure duration according to CCME (2007b) guidance. For some test organisms the chronic test durations were longer than those typically used. The lymnaid snail study was run for 28 days, and the daphnid bioassays were run for 21 days, longer than many chronic bioassays for invertebrates (generally four to 14 days). One of the fathead minnow bioassays was run for 34 days (De Schamphelaere et al. 2010), longer than typical fish bioassay durations (seven to 28 days).

This provides an additional measure of conservatism (longer exposure) to the proposed long term HC 5.

5.2.3 Minimum Data Criteria The acute SSD was based on 14 data points for 11 species. This includes one protist, seven invertebrates (four benthic and three planktonic crustacean), and three fish species (two non salmonid, one salmonid). It therefore meets the dataset requirements for a Type A shortterm CCME WQG (CCME 2007b). It is not clear if molybdenum should be considered a phytotoxin (thereby requiring a second acute data point for the acute SSD), because algae and plants were not uniformly the most sensitive taxa in acute and chronic datasets. Tubificids and fathead minnows showed the highest sensitivity in the acute SSD, and the chronic SSD revealed that green algae (P. subcapitata ) were the most sensitive, yet rainbow trout were more sensitive than the green alga Chlorella , and Lemna minor was the least sensitive of all taxa in the chronic dataset.

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The chronic dataset includes 15 datapoints for 10 species. It includes one plant, two algae, five invertebrates (one pelagic, one planktonic crustacean, and three benthic invertebrates), and two fish species (one salmonid and one nonsalmonid). The dataset therefore meets all the requirements of the type A longterm CCME WQO, with the exception that it is missing one chronic fish study. The key fish species at EKATI (lake trout, Arctic grayling, lake chub, round whitefish) are represented by available laboratory test species (rainbow trout and fathead minnows) (Appendix C; Rescan 2008). This reduces concern that fish are underprotected by the proposed longterm HC 5. As previously discussed the absence of data for a third fish species, specifically slimy sculpin, is not considered critical given that fish did not provide the most sensitive chronic endpoint and that the HC 5 was lower than the lowest chronic endpoint in the SSD.

5.2.4 Endpoints Used in SSD

For the acute SSD, 13 of the 14 data points were based on an LC 50 (or EC 50 immobilization, equivalent to mortality, for tubificids) and only one study reported a MATC, a lesspreferred endpoint. For the

chronic SSD, 11 of the studies reported an EC 10 , one reported an EC 12.5 , one reported an EC 25 , one reported an MATC, and one reported an EC 50 . Therefore, the majority of studies used the most preferred acute or chronic endpoints based on CCME (2007b) guidance.

5.2.5 Suitability of Species The acute SSD included data on all major biological groups, and matched relevant surrogate species with genera found at or near EKATI. An autotrophic euglenid protist was used to represent algae and plants in the acute dataset, because there were no studies on the dominant algae groups found at EKATI (cyanophytes, chlorophytes and chrysophytes). To represent zooplankton, two cladocerans were included in the acute dataset. No acute data were available for rotifers or copepods. Benthic and epibenthic invertebrates of the EKATI environment were reasonably well represented based on inclusion of a chironomid, a flatworm, a gammarid shrimp, an additional amphipod, and a tubificid worm. The fish community was represented by flannelmouth sucker, fathead minnow and rainbow trout. The slimy sculpin was not represented by available surrogate species but, as previously noted, this absence was not considered critical.

The chronic SSD included one macrophyte and two green algal species. This is moderately protective of the resident plant and algal communities at EKATI, although no toxicity data were available for chrysophytes or cyanophytes. Benthic invertebrates of the EKATI environment were represented by a chironomid and a snail. The snail served as a surrogate for fingernail clams present at EKATI (since no molybdenum data exist for these fingernail clams) (De Schamphelaere et al. 2010). Zooplankton were represented by a rotifer and two daphnids. This covers two of the three major zooplankton groups of EKATI lakes (copepod data were not available). The fish communities in lakes and streams of EKATI were represented by fathead minnows and rainbow trout, surrogates for lake chub, round whitefish, Arctic grayling and lake trout present at EKATI. No molybdenum data were available for burbot, longnose sucker, or slimy sculpin but again this was not considered a critical data gap.

5.2.6 Model Fit The robustness of a model fit to an SSD is related partly to the number and quality of available toxicological studies. This depends on fulfilling both the number of representative studies for each biological group, and also the total number of studies included in the SSD. Model fit also depends on the distribution of available data along the cumulative species distribution plot.

As previously noted, the minimum number of studies required to estimate an HC 5 ranges from 8 to 15 (Newman et al. 2000, Posthuma et al. 2002, Wheeler et al. 2002). This study exceeded the US EPA

BHP BILLITON CANADA INC. 53 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011 minimum recommendation of 8 studies as it used 11 and 10 species for the acute and chronic SSDs, respectively. CCME (2007b) does not have a minimum requirement for the number of data in an SSD, although minimum representation from specific taxonomic groups is specified and has been met, with the exception that it is missing one chronic fish study (see Section 5.2.3).

The tubificid worm, Tubifex tubifex (Khangarot 1991) provided an acute value of 52 mg/L, which is 12 times lower than the next most sensitive species (the fathead minnow lethal endpoint value is 644 mg/L). Therefore, the tubificid data point strongly drives the model fit in the lower tail of the

cumulative distribution of toxicity studies. It is this lower tail on which the HC 5 is estimated. The Khangarot (1991) study is considered robust because the 95% CL for the 48hr EC 50 were narrow (42.5 mg/L to 65.6 mg/L), and this study also reported 24hr and 96hr EC 50 values of 56 mg/L and 29 mg/L, respectively. These calculated endpoints support the conclusion that tubificids are relatively sensitive to molybdenum compared to other groups. However, as previously discussed both this group’s small contribution to the benthic community and the insulating effect of the sediments they live in (not present during the acute wateronly laboratory toxicity tests) obviate major concerns for possible ecological impacts. Further, the current molybdenum concentrations in the receiving environment are over 200 times less than the acute threshold for T. tubifex . Therefore no risk to this invertebrate group is predicted under current or reasonably foreseeable future conditions.

Comparison of the longterm SSWQO of 19 mg/L to the chronic endpoints indicates that all taxa included in the chronic SSD would be protected, since the lowest toxicity endpoint was 25 mg/L for

P. subcapitata . The estimated HC 5 and associated 95% CL (13.63 mg/L to 27.55 mg/L) indicate a good fit to the available toxicological data (based on the AndersonDarling test and visual inspection of the SSD plot).

5.3 BIOAVAILABILITY At typical pH levels observed in streams and lakes at EKATI (greater than pH 6), molybdenum is found almost entirely in the molybdate form (Rescan 2010). This molybdenum species is considered highly bioavailable to organisms. Precipitation, colloid or ligand binding, and adsorption of molybdate can occur, particularly with metal hydroxides (CCME 1999).

The lack of adjustment for any reduced bioavailability provides a measure of conservatism in the proposed SSWQOs. It is possible that some molybdenum may become bound or precipitated into sediment in lakes, thereby reducing bioavailable molybdenum to some degree, thus the lack of consideration of reduced bioavailability provides a measure of conservatism. Studies of molybdenum speciation would provide a more accurate assessment of bioavailability, but are not recommended at this time, because molybdenum concentrations in EKATI monitored lakes are far less than the chronic

HC 5 value (19 mg/L) presented here (Rescan 2010). Should molybdenum concentrations increase over time such that they could approach this HC 5 value, bioavailability studies would be useful in refining the HC 5.

5.4 TOLERANCE OF ORGANISMS The derivation of a SSWQO depends on the results of controlled, laboratorybased toxicity tests using laboratorybred, naive species. Laboratory cultures are not exposed to molybdenum at concentrations found in bioassays, thus they would not show capacity for metabolic acclimation (modified enzyme induction) or adaptation (population tolerance developed through natural selection) that could reduce their sensitivity to molybdenum. Species living under field conditions have shown the capacity for acclimation and adaptation to a number of metals (Klaverkamp et al. 1984; Posthuma and Van Straalen 1993; Chapman 2008). However, it is not known to what degree tolerance to molybdenum can be

54 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 UNCERTAINTY developed. The use of single chemical laboratory bioassays is a wellaccepted and conservative approach to provide clearly defined responses to be used in benchmark development, without considering the possibility of tolerance (CCME 2007b).

5.5 TOXICITY OF MIXTURES It is recognized that, within any effluent discharge into the natural environment, multiple substances may be present with possible interactions that may result in antagonism, additivity or synergism. While this study presents acute and chronic SSWQOs for molybdenum, it does not consider potential interaction effects with other substances. While molybdenum is known to compete with and inhibit copper uptake in ruminants (Underwood 1971), no other information on metals interactions with molybdenum was available.

BHP BILLITON CANADA INC. 55 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

6. Summary

BHP Billiton has commissioned several studies to address concerns regarding increasing molybdenum concentrations in waterbodies at EKATI. These studies include annual AEMP reporting (Rescan 2006, 2008, 2009, 2010) and an environmental risk assessment of molybdenum, as well as development of SSWQOs for this metal (Rescan 2006). This report provides an update to the SSWQOs developed in 2006, incorporating more recent acute and chronic toxicity studies from the literature and applying the updated CCME (2007b) methodology to derive Type A SSWQOs.

A total of 13 acceptable acute toxicity studies on 11 species were used to derive a shortterm SSWQO for

EKATI (223 mg/L) based on an acute HC 5. This proposed shortterm SSWQO is designated only for use in emergency situations involving shortterm (≤ 24 h) peaks in molybdenum concentrations in the aquatic environment.

A total of 15 acceptable chronic studies were available for 10 species, including a chronic alga test commissioned specifically for this study. The proposed longterm SSWQO was 19 mg/L, designated for use in routine water quality monitoring at EKATI.

The existing molybdenum concentrations in the lakes and streams of EKATI have ranged from below detection limits (0.001 mg/L) to 0.114 mg/L, much less than the newly derived chronic SSWQO of 19 mg/L.

Although this project was designed to establish monitoring criteria for EKATI, these results may be applicable at other sites across subArctic Canada, and may provide a suitable foundation for a future update of the CCME WQG for molybdenum.

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References

ANZECC/ARMCANZ. 2000. Australian and New Zealand guidelines for fresh and marine water quality . National Water Quality Management Strategy, Australian and New Zealand Environment Conservation Council, and Agriculture and Resource Management Council of Australia and New Zealand (ANZECC) (refer to http://www.environment.gov.au/water/quality/). Bentley, R.E. and K.J. Macek. 1973. Bioassay report submitted to Climax Molybdenum Company of Michigan. Prepared by Bionomics Inc., Wareham, MA, USA. Bionomics. 1973. Acute toxicity of sodium molybdate to bluegill (Lepomis macrochirus), rainbow trout (Salmo gairdneri), fathead minnow (Pimephales promelas), channel catfish (Ictalurus punctatus), water flea (Daphnia magna), and scud (Gammarus fasciatus). Report prepared for Climax Molybdenum Company of Michigan by Bionomics Inc, Wareham, MA, USA. Birge, W.J. 1978. Aquatic toxicology of trace elements of coal and fly ash. In Energy and Environmental Stress in Aquatic Ecosystems . Ed. J.H. Throp and J.W. Gibbons. United States Department of Energy Symposium Series. Report CONF771114. Birge, W.J., J.A. Black, A.G. Westerman and J.E. Hudson. 1980. Aquatic toxicity tests on inorganic element occurring in oil shale. In Oil Shale Symposium: Sampling, Analysis and Quality Assurance . Ed. C. Gale. National Technical Information Service, Springfield, VA, USA. EPA 600/980022. Borgmann, U., Y. Couillard, P. Doyle and D. G. Dixon. 2005. Toxicity of sixtythree metals and metalloids to Hyalella azteca at two levels of water hardness. Environmental Toxicology and Chemistry 24: 641652. Bringmann, G. and R. Kuhn. 1959. The toxic effects of waste water on aquatic bacteria, algae, and small crustaceans. GesundheitsIng 80: 115. British Columbia Ministry of Environment (BC MOE). 2010. A Compendium of Working Water Quality Guidelines for British Columbia . http://www.env.gov.bc.ca/wat/wq/BCguidelines/working. Updated January 2010. BrkovicPopovic, I. and M. Popovic. 1977. Effects of heavy metals on survival and respiration rate of tubificid worms: Part 1 – Effects on survival. Environmental Pollution 13: 6572. CCME. 1991. A protocol for the derivation of water quality guidelines for the protection of aquatic life. In Canadian Water Quality Guidelines: Appendix IX . Prepared by the Task Force on Water Quality Guidelines of the Canadian Council of Ministers of the Environment. Water Quality Branch. Environment Canada. Ottawa, ON, Canada. CCME. 1999. Canadian water quality guidelines for the protection of aquatic life: Molybdenum. Update 7.0 (September 2007) In Canadian Environmental Quality Guidelines, 1999 . Canadian Council of Ministers of the Environment. Winnipeg, MB, Canada. CCME. 2003. Guidance on the Sitespecific Application of Water Quality Guidelines in Canada: Procedures for Deriving Numerical Water Quality Objectives. Canadian Council of Ministers of the Environment. Winnipeg, MB, Canada. CCME. 2007a. Canadian water quality guidelines for the protection of aquatic life: Summary table. Updated December, 2007. In Canadian Environmental Quality Guidelines, 1999. Ed. Canadian Council of Ministers of the Environment. Winnipeg, MB, Canada.

BHP BILLITON CANADA INC. R1 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011

CCME. 2007b. A Protocol for the Derivation of Water Quality Guidelines for the Protection of Aquatic Life . Canadian Council of Ministers of the Environment. Winnipeg, MB, Canada. Chapman, P. M. 2008. Environmental risks of inorganic metals and metalloids: a continuing, evolving scientific odyssey. Human and Ecological Risk Assessment 14: 540. Chapman, P.M. and R.O. Brinkhurst. 1981. Seasonal changes in interstitial salinities and seasonal movements of subtidal benthic invertebrates in the Fraser River estuary, BC. Estuarine, Coastal and Shelf Science 12: 4966. Chapman, P.M. and R.O. Brinkhurst. 1984. Lethal and sublethal tolerances of aquatic oligochaetes with reference to their use as a biotic index of pollution. Hydrobiologia 115: 139144. Chapman, P.M., M.A. Farrell and R.O. Brinkhurst. 1982a. Relative tolerances of selected aquatic oligochaetes to individual pollutants and environmental factors. Aquatic Toxicology 2: 4767. Chapman, P.M., M.A. Farrell and R.O. Brinkhurst. 1982b. Relative tolerances of selected aquatic oligochaetes to combinations of pollutants and environmental factors. Aquatic Toxicology 2: 6978. Colborn, T. 1982. Measurement of low levels of molybdenum in the environment by using aquatic insects. Bulletin of Environmental Contamination and Toxicology 29: 422–428. Colmano, G. 1973. Molybdenum toxicity: abnormal cellular division of teratogenic appearance in Euglena gracilis . Bulletin of Environmental Contamination and Toxicology 9: 361364. Cornelis, R.H. 2005. Speciation of molybdenum. In Handbook of Elemental Speciation II: Species in the Environment, Food, Medicine, and Occupational Health Eds. Cornelis, R., H. Crews, J. Caruso and K.G. Heumann. John Wiley and Sons, Inc. Cruywagen, J.J. 2000. The catalytic scaffold of the haloalkanoic acid dehalogenase enzyme superfamily acts as a mold for the trigonal bipyramidal transition state. Advances in Inorganic Chemistry 49: 127182. Davies, T.D., J. Pickard and K.J. Hall. 2005. Acute molybdenum toxicity to rainbow trout and other fish. Journal of Environmental Engineering & Science 4: 481485. De Schamphelaere, K.A.C., W. Stubblefield, P. Rodriguez, K. Vleminckx and C.R. Janssen. 2010. The chronic toxicity of molybdate to freshwater organisms. I. Generating reliable effects data. Science of the Total Environment 408: 53625371. Diamantino, T.C., Guilhermino, L., Almeida, E. and Soares, A.M.V.M. 2000. Toxicity of sodium molybdate and sodium dichromate to Daphnia magna straus evaluated in acute, chronic and acetylcholinesterase inhibition tests. Ecotoxicology and Environmental Safety 45: 253259. Dwyer, F.J., S.A. Burch, C.G. Ingersoll and J.B. Hunn. 1992. Toxicity of trace element and salinity mixtures to striped bass (Morone saxatilis ) and Daphnia magna . Environmental Toxicology & Chemistry 11: 513520. Easterday, R.L. and R.F. Miller. 1963. The acute toxicity of molybdenum to the bluegill. Virginia Journal of Science 1962/1963: 199200. EC. 2006. Regulation (EC) No 1907/2006 of the European Parliament and of the council of 18 December 2006 concerning the registration, evaluation, authorisation and restriction of chemical substances (REACH), establishing a European Chemicals Agency, amending Directive 1999/45/EC and repealing Council Regulation (EEC) No 793/93 and Commission Regulation (EC) No 1488/94 as well as Council Directive 76/769/EEC and Commission Directives 91/155/EEC, 93/67/EEC, 93/105/EC and 2000/21/EC; 2006. European Commission, Brussels, Belgium.

R2 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 REFERENCES

Ecometrix. 2007. A Review of Environmental Management Criteria for Selenium and Molybdenum . Prepared for The Mine Environmental Neutral Drainage (MEND) Program. MEND Report No. 10.1.1. Eisler, J. 1989. Molybdenum Hazards to Fish, Wildlife and Invertebrates: A Synoptic Review . United States Fish and Wildlife Service. Biological Report 85. Ennevor, B.C. 1993. Effects of sodium molybdate and Endako mine effluent on developing embryos and alevin of coho salmon at Capilano river hatchery . Habitat Management Branch: Fisheries and Oceans Canada, Vancouver, BC, Canada. ENR 2006. Amphibians and Reptiles in the Northwest Territories Pamphlet . Updated 2006. Prepared by Northwest Territories Environment and Natural Resources. ENR 2012a. Wood Frog ( Lithobates sylvatica ). http://www.enr.gov.nt.ca/_live/pages/wpPages/Wood_Frog.aspx. (accessed February 2012). ENR 2012b. Boreal Chorus Frog ( Pseudacris maculata ). http://www.enr.gov.nt.ca/_live/pages/wpPages/Boreal_Chorus_Frog.aspx. (accessed February 2012). Environment Canada. 1998. Biological Test Method: Toxicity Tests Using Early Life Stages of Salmonid Fish (Rainbow Trout). Report EPS1/RM/28. 2nd Ed. Environmental Protection Services. Ottawa, ON, Canada. Environment Canada. 2007. Biological Test Method: Growth Inhibition Test using the Freshwater Algae . Environmental Protection Series, Report EPS1/RM/25. 2nd Ed. Method Development and Application Section, Environmental Science and Technology Centre, Science and Technology Branch. Ottawa, ON, Canada. European Union. 2008. Directive of the European Parliament and of the Council on Environmental Quality Standards in the Field of Water Policy, Amending and Subsequently Repealing Directives 82/176/EEC, 83/513/EEC, 84/156/EEC, 84/491/EEC and 86/280/EEC, and amending Directive 2000/60/EC. PECO_S 3644/08. Annex I Environmental Quality Standards for priority substances and certain other pollutants Part A: Environmental Quality Standards (EQS) September, 2008 . http://register.consilium.europa.eu/pdf/en/08/st03/st03644.en08.pdf (accessed November 2010). Fargasova, A. 1998. Comparative acute toxicity of Cu 2+ , Cu +, Mn 2+ , Mo 6+ , Ni 2+ , V 5+ to Chironomus plumosus larvae and Tubifex tubifex worms. Biologia 53: 315319. Fargasova, A. 1999. Ecotoxicological effects and uptake of metals (Cu+, Cu 2+ , Mn 2+ , Mo 6+ , Ni 2+ , V 5+ ) in freshwater alga Scenedesmus quadricaud a. Chemosphere 38: 11651173. GEI. 2009. Ambient water quality standards for molybdenum . Report prepared by GEI Consultants Inc. for Chevron Mining Inc., Questa, New Mexico, USA. Goettl, J.P. and P.H. Davies. 1976. Water pollution studies . Job Progress Report, Federal Aid Project F33R11. Colorado Division of Wildlife, Denver, CO, USA. Hamilton, S.J. and K.J. Buhl. 1990. Acute toxicity of boron, molybdenum, and selenium to fry Chinook salmon and coho salmon. Archives of Environmental Contamination and Toxicology 19: 366 373. Hamilton, S.J. and K.J. Buhl. 1997. Hazard evaluation of inorganics, singly and in mixtures, to flannelmouth sucker Catostomus latipinnis in the San Juan River, New Mexico. Ecotoxicology and Environmental Safety 38: 296:308.

BHP BILLITON CANADA INC. R3 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011

HRC. 1994. Sodium molybdate dihydrate — algal growth inhibition . Huntington Research Centre Report; Study commissioned by the International Molybdenum Association (IMOA). Jarrell, W.M., A.L. Page and A.A. Elseewi. 1980. Molybdenum in the environment. Residue Research 74:1–43. Khangarot, B.S. 1991. Toxicity of metals to a freshwater tubificid worm, Tubifex tubifex (Mőller) Bulletin of Environmental Contamination and Toxicology 46: 906912. Kienholz, E.W. 1977. Effects of environmental molybdenum levels upon wildlife. In Molybdenum in the Environment: The Geochemistry, Cycling, and Industrial Uses of Molybdenum . Eds. W.R. Chappell and K. Kellog Petersen. Marcel Dekker, Inc. New York, NY, USA. Kimball, G. 1978. The effects of lesser known metals and one organic to fathead minnows ( Pimephales promelas ) and Daphnia magna . Unpublished manuscript. Department of Entomology, Fisheries, and Wildlife, University of Minnesota, MN, USA. Klaverkamp, J., W. Macdonald, D. Duncan, and R. Wagemann. 1984. Metallothionein and acclimation to heavy metals in fish: A review. In Contaminant Effects on Fisheries . John Wiley and Sons, New York, NY, USA. Lynch, T.R., C.J. Popp and G.Z. Jacobi. 1988. Aquatic insects as environmental monitors of trace metal contamination: Red River, New Mexico. Water Air and Soil Pollution 42:1931. Martin, T.R. and D.M. Holdich. 1986. The acute lethal toxicity of heavy metals to peracarid crustaceans (with particular reference to freshwater asellids and gammarids). Water Research 20:1137 1147. McConnell, R.P. 1977. Toxicity of molybdenum to rainbow trout under laboratory conditions. In The Geochemistry, Cycling, and Industrial Uses of Molybdenum . Eds. W.R. Chappel, and K.K. Peterson. Marcel Dekker Inc., New York, NY, USA. McDevitt, C.A., J. Pickard, K. Andersen and C. Eickhoff. 1999. Toxicity of molybdenum to early life stages of rainbow trout in on site bioassays. In Proceedings of the 1999 Workshop on Molybdenum Issues in Reclamation. Eds. W.A. Brice, B. Hart, C. Howell. Kamloops, BC, Canada. McKee, J.E. and H.W. Wolf. 1963. Water Quality Criteria. 2nd Edition. The Resources Agency of California State Water Resources Control Board. Publication No. 3A. Sacramento, CA, USA. Naddy, R., T. LaPoint and S. Klaine. 1995. Toxicity of arsenic, molybdenum and selenium combinations to Ceriodaphnia dubia . Environmental Toxicology and Chemistry 14: 329336. NDEP. 2008. Aquatic life water quality criteria for molybdenum. Prepared for Nevada Division of Environmental Protection – Bureau of Water Quality Planning, by Tetra Tech Inc. Owings Mills, MD, USA. Newman, M.C., D.R. Ownby, L.C.A. Mezin, D.C. Powel, S.B.L. Christensen and B.A. Andersen. 2000. Applying speciessensitivity distributions in ecological risk assessment: assumptions of distribution type and sufficient number of species. Environmental Toxicology and Chemistry 19: 508515. Ontario MOE. 1998. Scientific criteria document for the development of an interim provincial water quality objective for molybdenum . Standards Development Branch. Toronto, ON, Canada. OECD. 1992. Report of the OECD workshop on the extrapolation of laboratory aquatic toxicity data to the real environment . Organization for Economic Cooperation and Development Environment. Monograph no. 59. Paris, France. Peterson, J. R. 1974. Molybdenum and fish. Industrial Water Engineering 11: 6.

R4 RESCAN ENVIRONMENTAL SERVICES LTD. (PROJ#64809501/REV C.1) FEBRUARY 2012 REFERENCES

Pickard, J., P. McKee and J. Stroiazzo. 1999. Site specific multispecies toxicity testing of sulphate and molybdenum spiked mining effluent and receiving water. In Proceedings of the 1999 Workshop on Molybdenum Issues in Reclamation Eds. W.A. Brice, B. Hart, C. Howell. Kamloops, BC, Canada. Posthuma, L. and N. Van Straalen. 1993. Heavymetal adaptation in terrestrial invertebrates: A review of occurrence, genetics, physiology and ecological consequences. Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology 106: 1138. Posthuma, L., T.P. Trass and G.W. Suter II. 2002. Species Sensitivity Distributions in Ecotoxicology . New York, NY, USA: Lewis Publishers. Pundir, R. and A. B. Saxena. 1990. Seasonal changes in the testes of fish Puntius ticto , and their relation to heavy metal toxicity. Bulletin of Environmental Contamination and Toxicology 45: 288293. Pyle, G. 2000. The toxicity and bioavailability of nickel and molybdenum to standard toxicitytest fish species, and fish species found in northern Canadian lakes . Ph.D. Dissertation. University of Saskatchewan, Saskatoon, SK, Canada. Reid, S.D. 2002. Physiological impact of acute molybdenum exposure in juvenile kokanee salmon (Oncorhychuss mykiss ). Comparative Biochemistry and Physiology Part C 133: 355367. Rescan. 2006. EKATI Diamond Mine. Tier 1 Aquatic Ecological Risk Assessment for Molybdenum. 2nd Draft. Prepared for BHP Billiton Canada Inc. by Rescan Environmental Services Ltd.: Vancouver, BC, Canada. Rescan. 2008. 2007 Aquatic Effects Monitoring Program (AEMP) Appendix B: Data Report . Prepared for BHP Billiton Canada Inc. by Rescan Environmental Services Ltd.: Vancouver, BC, Canada. Rescan. 2011a. EKATI Diamond Mine 2010 Aquatic Effects Monitoring Program. Appendix A: Evaluation of Effects. Prepared for BHP Billiton Canada Inc. by Rescan Environmental Services Ltd.: Yellowknife, NWT, Canada. Rescan. 2011b. Courageous Lake Project: Aquatic Resources: Aquatic Biology Baseline Study, 2010 . Prepared for Seabridge Gold Inc. by Rescan Environmental Services Ltd.: Yellowknife, NWT, Canada. RIVM. 1997. Maximum permissible concentrations and negligible concentrations for metals, taking background concentrations into account. In Environmental Risk Limits in the Netherlands . Report 601501001. Eds. T. Crommentuijn, M.D. Polder and E.J. van de Plassche. Rijksinstituut Voor Volksgezondheid en Milieu (National Institute of Public Health and the Environment). Holland. RIVM. 2005. Environmental Risk Limits for Nine Trace Elements . Rijksinstituut Voor Volksgezondheid en Milieu (National Institute for Public Health and the Environment). Holland. RIVM report no. 601501029. Rodney, S.I. and D.R.J. Moore. 2008. Development of an ExcelBased Tool for Fitting and Evaluating Species Sensitivity Distributions . Prepared for Environment Canada by Intrinsik Environmental Sciences Inc. Ottawa, ON. Saiki, M.K., M.R. Jennings and W.G. Brumbaugh. 1993. Boron, molybdenum, and selenium in aquatic food chains from the lower San Joaquin and its tributaries, California. Archives of Environmental Contamination and Toxicology 24: 307319.

BHP BILLITON CANADA INC. R5 SITE SPECIFIC WATER QUALITY OBJECTIVE FOR MOLYBDENUM, 2011

Sakaguchi, T., A. Nakajima and T. Horikoshi. 1981. Studies on the accumulation of heavy metal elements in biological systems: accumulation of molybdenum by green microalgae. European Journal of Applied Microbiology and Biotechnology 12: 8489. Steeg, P., P. Hanson and H. Paerl. 1986. Growthlimiting quantities and accumulation of molybdenum in Anabaena oscillarioides (Cyanobacteria). Hydrobiologia 140: 143147. Stephan, C.E., D. Mount, D. Hansen, J. Gentile, G. Chapman, and W. Brungs. 1985. Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Life and Its Uses. United States Environmental Protection Agency. Document PB85227049. Office of Research and Development Environmental Research Laboratories, Duluth, Minnesota, USA. Suttle, N. 1991. The interactions between copper, molybdenum, and sulphur in ruminant nutrition. Annual Review of Nutrition 11: 121140. Swain, L.G. 1986. Water Quality Criteria for Molybdenum . Ministry of Environment Lands and Parks Province of British Columbia. Victoria, BC, Canada. Tarswell, C.M. and C. Henderson. 1960. Toxicity of less common metals to fish. Industrial Wastes 2: 12. Tong, S.S.C., W.D. Youngs, W.H. Gutemann and D.J. Lisk. 1974. Trace metals in Lake Cayuga lake trout (Salvelinus namaycush ) in relation to age. Journal of the Fisheries Research Board of Canada 31: 238–239. Underwood, E.J. 1971. Molybdenum: Trace Elements in Human and Animal Nutrition . 116140. New York, NY, USA: Academic Press. US EPA. 1985. Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses . Duluth, MN, USA: United States Environmental Protection Agency Office of Research and Development. US EPA. 2010. National Recommended Water Quality Criteria . http://water.epa.gov/scitech/swguidance/waterquality/standards/current/upload/nrwqc 2009.pdf United States Environmental Protection Agency. accessed November 2010). Van de Meent, D., T. Aldenberg, J Canton, C. Van Gestel and W. Sloof. 1990. Desire for levels. Background study for the policy document. Report no. 670101002. In Setting Environmental Quality Standards for Water and Soil . Holland. Viollier, E., D. Jezequel, G. Michard, M Pepe, G Sarazin and P Alberic. 1995. Geochemical study of a crater lake (Pavin Lake, France): Traceelement behaviour in the monimolimnion. Chemical Geology 125: 6172. Wheeler, J.R., E.M.P. Grist, K.M.Y. Leung, D. Morrit and M. Crane. 2002. Species sensitivity distributions: data and model choice. Marine Pollution Bulletin 45: 192202. Woodward, D.F., R.G. Riley, M.G. Henry, J.S. Meyer and T.R. Garland. 1985. Leaching of retorted oil shale: Assessing the toxicity to Colorado squawfish, fathead minnows and two foodchain organisms. Transactions of the American Fisheries Society 114:887–894.

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Appendix A Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994 to 2011

Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Counts 14-Aug-97 <0.00005 Counts 1-Aug-00 <0.00006 Counts 14-Aug-97 <0.00005 Counts 1-Aug-00 <0.00006 Counts 14-Aug-97 <0.00005 Counts 4-Sep-00 <0.00006 Counts 30-Jun-98 <0.00006 Counts 4-Sep-00 <0.00006 Counts 30-Jun-98 <0.00006 Counts 4-Sep-00 <0.00006 Counts 30-Jun-98 <0.00006 Counts 4-Sep-00 <0.00006 Counts 30-Jun-98 <0.00006 Counts 5-Jul-01 <0.00006 Counts 30-Jun-98 <0.00006 Counts 5-Jul-01 <0.00006 Counts 30-Jun-98 <0.00006 Counts 5-Jul-01 <0.00006 Counts 18-Jul-98 <0.00006 Counts 5-Jul-01 <0.00006 Counts 18-Jul-98 <0.00006 Counts 30-Jul-01 <0.00006 Counts 18-Jul-98 <0.00006 Counts 30-Jul-01 <0.00006 Counts 18-Jul-98 <0.00006 Counts 30-Jul-01 <0.00006 Counts 18-Jul-98 <0.00006 Counts 30-Jul-01 <0.00006 Counts 18-Jul-98 <0.00006 Counts 2-Sep-01 <0.00006 Counts 29-Jul-98 <0.00006 Counts 2-Sep-01 <0.00006 Counts 29-Jul-98 <0.00006 Counts 2-Sep-01 <0.00006 Counts 29-Jul-98 <0.00006 Counts 2-Sep-01 <0.00006 Counts 29-Jul-98 <0.00006 Counts 23-Apr-02 <0.00006 Counts 29-Jul-98 <0.00006 Counts 23-Apr-02 <0.00006 Counts 29-Jul-98 <0.00006 Counts 23-Apr-02 <0.00006 Counts 14-Aug-98 <0.00006 Counts 23-Apr-02 <0.00006 Counts 14-Aug-98 <0.00006 Counts 10-Jul-02 <0.00006 Counts 14-Aug-98 <0.00006 Counts 10-Jul-02 <0.00006 Counts 14-Aug-98 <0.00006 Counts 10-Jul-02 <0.00006 Counts 14-Aug-98 <0.00006 Counts 10-Jul-02 <0.00006 Counts 14-Aug-98 <0.00006 Counts 7-Aug-02 <0.00006 Counts 10-Sep-98 <0.00006 Counts 7-Aug-02 <0.00006 Counts 10-Sep-98 <0.00006 Counts 7-Aug-02 <0.00006 Counts 10-Sep-98 <0.00006 Counts 7-Aug-02 <0.00006 Counts 10-Sep-98 <0.00006 Counts 6-Sep-02 <0.00006 Counts 10-Sep-98 <0.00006 Counts 6-Sep-02 <0.00006 Counts 10-Sep-98 <0.00006 Counts 6-Sep-02 <0.00006 Counts 09-Jul-99 - Counts 6-Sep-02 <0.00006 Counts 09-Jul-99 - Counts 13-Apr-03 <0.00006 Counts 09-Jul-99 - Counts 13-Apr-03 <0.00006 Counts 09-Jul-99 - Counts 13-Apr-03 <0.00006 Counts 09-Jul-99 - Counts 13-Apr-03 <0.00006 Counts 09-Jul-99 - Counts 2-Jul-03 <0.00006 Counts 08-Aug-99 - Counts 2-Jul-03 <0.00006 Counts 08-Aug-99 - Counts 7-Aug-03 <0.00006 Counts 08-Aug-99 - Counts 7-Aug-03 <0.00006 Counts 08-Aug-99 - Counts 10-Sep-03 <0.00006 Counts 08-Aug-99 - Counts 10-Sep-03 <0.00006 Counts 08-Aug-99 - Counts 17-Apr-04 <0.000050 Counts 04-Sep-99 - Counts 17-Apr-04 <0.000050 Counts 04-Sep-99 - Counts 17-Apr-04 <0.000050 Counts 04-Sep-99 - Counts 17-Apr-04 <0.000050 Counts 04-Sep-99 - Counts 9-Jul-04 <0.000050 Counts 04-Sep-99 - Counts 9-Jul-04 <0.000050 Counts 04-Sep-99 - Counts 12-Aug-04 <0.000050 Counts 30-Jun-00 <0.00006 Counts 12-Aug-04 <0.000050 Counts 30-Jun-00 <0.00006 Counts 11-Sep-04 <0.000050 Counts 30-Jun-00 <0.00006 Counts 11-Sep-04 <0.000050 Page 1 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Counts 30-Jun-00 <0.00006 Counts 24-Apr-05 <0.000050 Counts 01-Aug-00 <0.00006 Counts 24-Apr-05 <0.000050 Counts 01-Aug-00 <0.00006 Counts 24-Apr-05 <0.000050 Counts 24-Apr-05 <0.000050 Counts 7-Sep-09 <0.000050 Counts 14-Jul-05 <0.00005 Counts 7-Sep-09 <0.000050 Counts 14-Jul-05 <0.00005 Counts 7-Sep-09 <0.000050 Counts 07-Aug-05 <0.00005 Counts 7-Aug-10 <0.000050 Counts 07-Aug-05 <0.00005 Counts 7-Aug-10 <0.000050 Counts 07-Aug-05 <0.00005 Counts 7-Aug-10 <0.000050 Counts 01-Sep-05 <0.00005 Counts 7-Aug-10 <0.000050 Counts 01-Sep-05 <0.00005 Counts 7-Aug-10 <0.000050 Counts 22-Apr-06 <0.000050 Counts 7-Aug-10 0.000101 Counts 22-Apr-06 <0.000050 Counts 14-Apr-10 <0.000050 Counts 22-Apr-06 <0.000050 Counts 14-Apr-10 <0.000050 Counts 22-Apr-06 <0.000050 Counts 14-Apr-10 <0.000050 Counts 30-Jun-06 <0.000050 Counts 14-Apr-10 <0.000050 Counts 30-Jun-06 0.000121 Counts 5-Aug-11 <0.000050 Counts 04-Aug-06 <0.000050 Counts 5-Aug-11 <0.000050 Counts 04-Aug-06 <0.000050 Counts 5-Aug-11 <0.000050 Counts 07-Sep-06 0.000059 Counts 5-Aug-11 <0.000050 Counts 07-Sep-06 <0.000050 Counts 5-Aug-11 <0.000050 Counts 13-Jul-07 <0.000050 Counts 5-Aug-11 <0.000050 Counts 13-Jul-07 <0.000050 Counts 26-Apr-11 <0.000050 Counts 06-Aug-07 <0.000050 Counts 26-Apr-11 <0.000050 Counts 06-Aug-07 <0.000050 Counts 26-Apr-11 <0.000050 Counts 06-Aug-07 <0.000050 Counts 26-Apr-11 <0.000050 Counts 06-Aug-07 <0.000050 Cujo 11-Jul-99 - Counts 06-Aug-07 <0.000050 Cujo 11-Jul-99 - Counts 06-Aug-07 <0.000050 Cujo 11-Jul-99 - Counts 24-Apr-07 <0.000050 Cujo 11-Jul-99 - Counts 24-Apr-07 <0.000050 Cujo 11-Jul-99 - Counts 24-Apr-07 <0.000050 Cujo 11-Jul-99 - Counts 24-Apr-07 <0.000050 Cujo 8-Aug-99 - Counts 12-Sep-07 <0.000050 Cujo 8-Aug-99 - Counts 12-Sep-07 <0.000050 Cujo 8-Aug-99 - Counts 12-Sep-07 <0.000050 Cujo 8-Aug-99 - Counts 03-May-08 <0.000050 Cujo 8-Aug-99 - Counts 03-May-08 <0.000050 Cujo 8-Aug-99 - Counts 03-May-08 <0.000050 Cujo 5-Sep-99 - Counts 03-May-08 <0.000050 Cujo 5-Sep-99 - Counts 08-Jul-08 0.000123 Cujo 5-Sep-99 - Counts 08-Jul-08 <0.000050 Cujo 5-Sep-99 - Counts 31-Jul-08 <0.000050 Cujo 5-Sep-99 - Counts 31-Jul-08 <0.000050 Cujo 5-Sep-99 - Counts 31-Jul-08 <0.000050 Cujo 30-Jun-00 <0.00006 Counts 31-Jul-08 <0.000050 Cujo 30-Jun-00 <0.00006 Counts 31-Jul-08 <0.000050 Cujo 30-Jun-00 <0.00006 Counts 31-Jul-08 <0.000050 Cujo 30-Jun-00 <0.00006 Counts 05-Sep-08 <0.000050 Cujo 31-Jul-00 <0.00006 Counts 05-Sep-08 <0.000050 Cujo 31-Jul-00 <0.00006 Counts 17-May-09 <0.000050 Cujo 31-Jul-00 <0.00006 Counts 17-May-09 <0.000050 Cujo 31-Jul-00 <0.00006 Counts 17-May-09 <0.000050 Cujo 4-Sep-00 <0.00006 Counts 17-May-09 <0.000050 Cujo 4-Sep-00 <0.00006 Page 2 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Counts 06-Jul-09 <0.000050 Cujo 4-Sep-00 <0.00006 Counts 06-Jul-09 <0.000050 Cujo 4-Sep-00 <0.00006 Counts 06-Jul-09 <0.000050 Cujo 6-Jul-01 <0.00006 Counts 01-Aug-09 <0.000050 Cujo 6-Jul-01 <0.00006 Counts 01-Aug-09 <0.000050 Cujo 6-Jul-01 <0.00006 Counts 01-Aug-09 <0.000050 Cujo 30-Jul-01 <0.00006 Counts 31-Jul-09 <0.000050 Cujo 30-Jul-01 <0.00006 Cujo 30-Jul-01 <0.00006 Cujo 6-Sep-06 0.00306 Cujo 02-Sep-01 0.00013 Cujo 6-Sep-06 0.00329 Cujo 02-Sep-01 0.00013 Cujo 15-Jul-07 0.00135 Cujo 02-Sep-01 0.00014 Cujo 15-Jul-07 0.00127 Cujo 02-Sep-01 0.00013 Cujo 15-Jul-07 0.00129 Cujo 23-Apr-02 0.00075 Cujo 5-Aug-07 0.00151 Cujo 23-Apr-02 0.00082 Cujo 5-Aug-07 0.00152 Cujo 23-Apr-02 0.00099 Cujo 5-Aug-07 0.00152 Cujo 23-Apr-02 0.00078 Cujo 5-Aug-07 0.000963 Cujo 08-Jul-02 0.00032 Cujo 5-Aug-07 0.00152 Cujo 08-Jul-02 0.00033 Cujo 5-Aug-07 0.00144 Cujo 08-Jul-02 0.00033 Cujo 27-Apr-07 0.002 Cujo 08-Jul-02 0.00031 Cujo 27-Apr-07 0.00198 Cujo 07-Aug-02 0.00032 Cujo 27-Apr-07 0.00186 Cujo 07-Aug-02 0.00032 Cujo 27-Apr-07 0.00186 Cujo 07-Aug-02 0.00031 Cujo 12-Sep-07 0.00136 Cujo 07-Aug-02 0.00032 Cujo 12-Sep-07 0.00131 Cujo 05-Sep-02 0.00025 Cujo 3-May-08 0.000792 Cujo 05-Sep-02 0.00027 Cujo 3-May-08 0.000801 Cujo 05-Sep-02 0.00025 Cujo 3-May-08 0.000863 Cujo 05-Sep-02 0.00026 Cujo 3-May-08 0.000779 Cujo 13-Apr-03 0.0011 Cujo 7-Jul-08 0.000905 Cujo 13-Apr-03 0.00103 Cujo 7-Jul-08 0.000817 Cujo 13-Apr-03 0.00097 Cujo 26-Jul-08 0.00156 Cujo 13-Apr-03 0.00124 Cujo 26-Jul-08 0.00149 Cujo 06-Jul-03 0.00061 Cujo 26-Jul-08 0.00141 Cujo 06-Jul-03 0.00056 Cujo 26-Jul-08 0.00164 Cujo 04-Aug-03 0.00128 Cujo 26-Jul-08 0.0015 Cujo 04-Aug-03 0.00128 Cujo 26-Jul-08 0.00153 Cujo 09-Sep-03 0.00213 Cujo 10-Sep-08 0.00112 Cujo 09-Sep-03 0.00214 Cujo 10-Sep-08 0.00112 Cujo 11-Jul-04 0.000621 Cujo 3-May-09 0.00128 Cujo 11-Jul-04 0.000669 Cujo 3-May-09 0.0013 Cujo 10-Aug-04 0.000659 Cujo 3-May-09 0.0012 Cujo 10-Aug-04 0.00071 Cujo 3-May-09 0.00126 Cujo 02-Sep-04 0.000629 Cujo 6-Jul-09 0.000753 Cujo 02-Sep-04 0.000609 Cujo 6-Jul-09 0.000785 Cujo 02-Sep-04 0.000595 Cujo 31-Jul-09 0.000926 Cujo 17-Apr-04 0.00157 Cujo 31-Jul-09 0.00104 Cujo 17-Apr-04 0.00167 Cujo 31-Jul-09 0.000905 Cujo 17-Apr-04 0.00148 Cujo 31-Jul-09 0.000922 Cujo 17-Apr-04 0.00132 Cujo 31-Jul-09 0.00101 Cujo 24-Apr-05 0.00273 Cujo 31-Jul-09 0.000929 Cujo 24-Apr-05 0.00316 Cujo 8-Sep-09 0.00118 Cujo 24-Apr-05 0.00278 Cujo 8-Sep-09 0.00115 Cujo 24-Apr-05 0.00273 Cujo 4-Aug-10 0.000996 Cujo 14-Jul-05 0.00134 Cujo 4-Aug-10 0.00106 Page 3 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Cujo 14-Jul-05 0.00127 Cujo 4-Aug-10 0.00107 Cujo 09-Aug-05 0.00137 Cujo 4-Aug-10 0.00106 Cujo 09-Aug-05 0.00132 Cujo 4-Aug-10 0.00104 Cujo 09-Aug-05 0.00133 Cujo 4-Aug-10 0.00108 Cujo 01-Sep-05 0.00121 Cujo 16-Apr-10 0.00135 Cujo 01-Sep-05 0.00122 Cujo 16-Apr-10 0.00118 Cujo 22-Apr-06 0.00111 Cujo 4-Aug-11 0.00179 Cujo 22-Apr-06 0.0011 Cujo 4-Aug-11 0.00149 Cujo 01-Jul-06 0.000774 Cujo 4-Aug-11 0.00149 Cujo 01-Jul-06 0.000758 Cujo 4-Aug-11 0.00149 Cujo 04-Aug-06 0.00207 Cujo 4-Aug-11 0.00148 Cujo 04-Aug-11 0.00148 Grizzly 2-Sep-99 - Cujo 26-Apr-11 0.00236 Grizzly 2-Sep-99 - Cujo 26-Apr-11 0.00235 Grizzly 2-Sep-99 - Cujo 26-Apr-11 0.00194 Grizzly 2-Sep-99 - Cujo 26-Apr-11 0.00195 Grizzly 2-Sep-99 - Grizzly 20-Jun-94 <0.001 Grizzly 2-Sep-99 - Grizzly 20-Jun-94 <0.001 Grizzly 4-Jul-00 <0.00006 Grizzly 20-Jun-94 <0.001 Grizzly 4-Jul-00 <0.00006 Grizzly 20-Jun-94 <0.001 Grizzly 4-Jul-00 <0.00006 Grizzly 20-Jun-94 <0.001 Grizzly 4-Jul-00 <0.00006 Grizzly 13-Aug-94 <0.001 Grizzly 4-Aug-00 <0.00006 Grizzly 13-Aug-94 <0.001 Grizzly 4-Aug-00 <0.00006 Grizzly 13-Aug-94 <0.001 Grizzly 4-Aug-00 <0.00006 Grizzly 13-Aug-94 <0.001 Grizzly 4-Aug-00 <0.00006 Grizzly 13-Aug-94 <0.001 Grizzly 5-Sep-00 <0.00006 Grizzly 07-Aug-97 <0.00005 Grizzly 5-Sep-00 <0.00006 Grizzly 07-Aug-97 <0.00005 Grizzly 5-Sep-00 <0.00006 Grizzly 07-Aug-97 <0.00005 Grizzly 5-Sep-00 <0.00006 Grizzly 28-Jun-98 <0.00006 Grizzly 11-Jul-01 <0.00006 Grizzly 28-Jun-98 <0.00006 Grizzly 11-Jul-01 <0.00006 Grizzly 28-Jun-98 <0.00006 Grizzly 11-Jul-01 <0.00006 Grizzly 28-Jun-98 <0.00006 Grizzly 11-Jul-01 <0.00006 Grizzly 28-Jun-98 <0.00006 Grizzly 7-Aug-01 <0.00006 Grizzly 28-Jun-98 <0.00006 Grizzly 7-Aug-01 <0.00006 Grizzly 14-Jul-98 0.00007 Grizzly 7-Aug-01 <0.00006 Grizzly 14-Jul-98 <0.00006 Grizzly 7-Aug-01 <0.00006 Grizzly 14-Jul-98 <0.00006 Grizzly 29-Aug-01 <0.00006 Grizzly 14-Jul-98 <0.00006 Grizzly 29-Aug-01 <0.00006 Grizzly 14-Jul-98 <0.00006 Grizzly 29-Aug-01 <0.00006 Grizzly 14-Jul-98 <0.00006 Grizzly 29-Aug-01 <0.00006 Grizzly 27-Jul-98 <0.00006 Grizzly 5-Jul-02 <0.00006 Grizzly 27-Jul-98 <0.00006 Grizzly 5-Jul-02 <0.00006 Grizzly 27-Jul-98 <0.00006 Grizzly 5-Jul-02 <0.00006 Grizzly 27-Jul-98 <0.00006 Grizzly 5-Jul-02 <0.00006 Grizzly 27-Jul-98 <0.00006 Grizzly 2-Aug-02 <0.00006 Grizzly 27-Jul-98 <0.00006 Grizzly 2-Aug-02 <0.00006 Grizzly 09-Aug-98 <0.00006 Grizzly 2-Aug-02 <0.00006 Grizzly 09-Aug-98 <0.00006 Grizzly 2-Aug-02 <0.00006 Grizzly 09-Aug-98 <0.00006 Grizzly 2-Sep-02 <0.00006 Grizzly 09-Aug-98 <0.00006 Grizzly 2-Sep-02 <0.00006 Grizzly 09-Aug-98 <0.00006 Grizzly 2-Sep-02 <0.00006 Grizzly 09-Aug-98 <0.00006 Grizzly 2-Sep-02 <0.00006 Grizzly 02-Sep-98 <0.00006 Grizzly 16-Apr-03 0.00024 Page 4 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Grizzly 02-Sep-98 <0.00006 Grizzly 16-Apr-03 0.00008 Grizzly 02-Sep-98 <0.00006 Grizzly 16-Apr-03 0.00006 Grizzly 02-Sep-98 <0.00006 Grizzly 16-Apr-03 <0.00006 Grizzly 02-Sep-98 <0.00006 Grizzly 4-Jul-03 <0.00006 Grizzly 02-Sep-98 <0.00006 Grizzly 8-Aug-03 <0.00006 Grizzly 07-Jul-99 - Grizzly 8-Aug-03 <0.00006 Grizzly 07-Jul-99 - Grizzly 5-Sep-03 <0.00006 Grizzly 07-Jul-99 - Grizzly 4-Jul-03 <0.00006 Grizzly 07-Jul-99 - Grizzly 8-Jul-04 <0.000050 Grizzly 06-Aug-99 - Grizzly 8-Jul-04 <0.000050 Grizzly 06-Aug-99 - Grizzly 7-Aug-04 <0.000050 Grizzly 06-Aug-99 - Grizzly 7-Aug-04 <0.000050 Grizzly 06-Aug-99 - Grizzly 10-Sep-04 <0.000050 Grizzly 06-Aug-99 - Grizzly 10-Sep-04 <0.000050 Grizzly 06-Aug-99 - Grizzly 19-Apr-04 <0.000050 Grizzly 19-Apr-04 <0.000050 Grizzly 3-Aug-09 <0.000050 Grizzly 19-Apr-04 <0.000050 Grizzly 3-Aug-09 <0.000050 Grizzly 24-Apr-05 <0.000050 Grizzly 4-Sep-09 <0.000050 Grizzly 24-Apr-05 <0.000050 Grizzly 4-Sep-09 <0.000050 Grizzly 24-Apr-05 <0.000050 Grizzly 4-Sep-09 <0.000050 Grizzly 24-Apr-05 <0.000050 Grizzly 4-Aug-10 <0.000050 Grizzly 12-Jul-05 <0.00005 Grizzly 4-Aug-10 <0.000050 Grizzly 12-Jul-05 <0.00005 Grizzly 4-Aug-10 <0.000050 Grizzly 07-Aug-05 <0.00005 Grizzly 4-Aug-10 <0.000050 Grizzly 07-Aug-05 <0.00005 Grizzly 4-Aug-10 <0.000050 Grizzly 04-Sep-05 <0.00005 Grizzly 4-Aug-10 <0.000050 Grizzly 04-Sep-05 <0.00005 Grizzly 12-Apr-10 <0.000050 Grizzly 24-Apr-06 <0.000050 Grizzly 12-Apr-10 <0.000050 Grizzly 24-Apr-06 <0.000050 Grizzly 12-Apr-10 <0.000050 Grizzly 24-Apr-06 <0.000050 Grizzly 12-Apr-10 <0.000050 Grizzly 24-Apr-06 <0.000050 Grizzly 1-Aug-11 <0.000050 Grizzly 30-Jun-06 <0.000050 Grizzly 1-Aug-11 <0.000050 Grizzly 30-Jun-06 <0.000050 Grizzly 1-Aug-11 <0.000050 Grizzly 07-Aug-06 <0.000050 Grizzly 1-Aug-11 <0.000050 Grizzly 07-Aug-06 <0.000050 Grizzly 1-Aug-11 <0.000050 Grizzly 07-Sep-06 0.000279 Grizzly 1-Aug-11 <0.000050 Grizzly 07-Sep-06 0.000092 Grizzly 28-Apr-11 <0.000050 Grizzly 14-Jul-07 <0.000050 Grizzly 28-Apr-11 <0.000050 Grizzly 14-Jul-07 <0.000050 Grizzly 28-Apr-11 <0.000050 Grizzly 04-Aug-07 <0.000050 Grizzly 28-Apr-11 <0.000050 Grizzly 04-Aug-07 <0.000050 Kodiak 2-Jul-94 <0.001 Grizzly 04-Aug-07 <0.000050 Kodiak 2-Jul-94 <0.001 Grizzly 04-Aug-07 <0.000050 Kodiak 2-Jul-94 <0.001 Grizzly 04-Aug-07 <0.000050 Kodiak 2-Jul-94 <0.001 Grizzly 04-Aug-07 <0.000050 Kodiak 2-Jul-94 <0.001 Grizzly 26-Apr-07 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 26-Apr-07 <0.000050 Kodiak 19-Aug-94 0.001 Grizzly 26-Apr-07 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 26-Apr-07 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 10-Sep-07 0.000072 Kodiak 19-Aug-94 0.001 Grizzly 10-Sep-07 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 06-May-08 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 06-May-08 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 06-May-08 0.000101 Kodiak 19-Aug-94 <0.001 Page 5 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Grizzly 06-May-08 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 06-Jul-08 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 06-Jul-08 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 27-Jul-08 <0.000050 Kodiak 19-Aug-94 0.001 Grizzly 27-Jul-08 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 27-Jul-08 <0.000050 Kodiak 19-Aug-94 <0.001 Grizzly 27-Jul-08 <0.000050 Kodiak 10-Aug-95 <0.001 Grizzly 27-Jul-08 <0.000050 Kodiak 10-Aug-95 <0.001 Grizzly 27-Jul-08 <0.000050 Kodiak 10-Aug-95 <0.001 Grizzly 09-Sep-08 0.000487 Kodiak 18-Apr-96 0.000035 Grizzly 28-Apr-09 <0.000050 Kodiak 28-Jul-96 0.00011 Grizzly 28-Apr-09 <0.000050 Kodiak 28-Jul-96 0.00012 Grizzly 28-Apr-09 <0.000050 Kodiak 28-Jul-96 0.00011 Grizzly 11-Jul-09 <0.000050 Kodiak 28-Jul-96 0.00011 Grizzly 11-Jul-09 <0.000050 Kodiak 28-Jul-96 0.00012 Grizzly 03-Aug-09 0.000206 Kodiak 28-Jul-96 0.00012 Grizzly 03-Aug-09 <0.000050 Kodiak 28-Jul-96 0.00013 Grizzly 03-Aug-09 <0.000050 Kodiak 28-Jul-96 0.00013 Grizzly 03-Aug-09 <0.000050 Kodiak 28-Jul-96 0.00013 Kodiak 09-Aug-97 Kodiak 25-Aug-98 - Kodiak 09-Aug-97 0.00018 Kodiak 25-Aug-98 - Kodiak 09-Aug-97 Kodiak 25-Aug-98 - Kodiak 09-Aug-97 0.00019 Kodiak 19-Apr-99 0.0006 Kodiak 26-Jun-98 - Kodiak 19-Apr-99 0.0004 Kodiak 26-Jun-98 - Kodiak 13-Jul-99 - Kodiak 26-Jun-98 - Kodiak 13-Jul-99 - Kodiak 26-Jun-98 - Kodiak 13-Jul-99 - Kodiak 26-Jun-98 - Kodiak 13-Jul-99 - Kodiak 26-Jun-98 - Kodiak 13-Jul-99 - Kodiak 03-Jul-98 0.00193 Kodiak 10-Aug-99 - Kodiak 03-Jul-98 0.00195 Kodiak 10-Aug-99 - Kodiak 03-Jul-98 0.00193 Kodiak 10-Aug-99 - Kodiak 03-Jul-98 0.00195 Kodiak 10-Aug-99 - Kodiak 03-Jul-98 0.00202 Kodiak 10-Aug-99 - Kodiak 03-Jul-98 0.00196 Kodiak 7-Sep-99 - Kodiak 14-Jul-98 - Kodiak 7-Sep-99 - Kodiak 14-Jul-98 - Kodiak 7-Sep-99 - Kodiak 14-Jul-98 - Kodiak 7-Sep-99 - Kodiak 14-Jul-98 - Kodiak 7-Sep-99 - Kodiak 14-Jul-98 - Kodiak 6-Apr-00 - Kodiak 15-Jul-98 0.00227 Kodiak 6-Apr-00 - Kodiak 15-Jul-98 0.00186 Kodiak 10-Apr-00 - Kodiak 15-Jul-98 0.00188 Kodiak 10-Apr-00 - Kodiak 15-Jul-98 0.00186 Kodiak 27-Jun-00 - Kodiak 15-Jul-98 0.00188 Kodiak 27-Jun-00 - Kodiak 15-Jul-98 0.00188 Kodiak 27-Jun-00 - Kodiak 28-Jul-98 0.00196 Kodiak 27-Jun-00 - Kodiak 28-Jul-98 0.00197 Kodiak 29-Jul-00 0.00016 Kodiak 28-Jul-98 0.00193 Kodiak 29-Jul-00 0.00016 Kodiak 28-Jul-98 0.00195 Kodiak 29-Jul-00 0.00016 Kodiak 28-Jul-98 0.00197 Kodiak 29-Jul-00 0.00015 Kodiak 28-Jul-98 0.00196 Kodiak 30-Aug-00 0.00024 Kodiak 28-Jul-98 - Kodiak 30-Aug-00 0.00024 Kodiak 28-Jul-98 - Kodiak 30-Aug-00 0.00025 Page 6 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Kodiak 28-Jul-98 - Kodiak 30-Aug-00 0.00024 Kodiak 28-Jul-98 - Kodiak 23-Apr-01 0.00015 Kodiak 28-Jul-98 - Kodiak 23-Apr-01 0.00014 Kodiak 28-Jul-98 - Kodiak 23-Apr-01 0.00014 Kodiak 11-Aug-98 0.0016 Kodiak 23-Apr-01 0.00013 Kodiak 11-Aug-98 0.00162 Kodiak 30-Jun-01 0.00009 Kodiak 11-Aug-98 0.00163 Kodiak 30-Jun-01 0.00009 Kodiak 11-Aug-98 0.00155 Kodiak 30-Jun-01 0.00009 Kodiak 11-Aug-98 0.00155 Kodiak 30-Jun-01 0.00009 Kodiak 11-Aug-98 0.00157 Kodiak 28-Jul-01 0.004 Kodiak 11-Aug-98 - Kodiak 28-Jul-01 0.00046 Kodiak 11-Aug-98 - Kodiak 28-Jul-01 0.00049 Kodiak 11-Aug-98 - Kodiak 29-Aug-01 0.00017 Kodiak 11-Aug-98 - Kodiak 29-Aug-01 0.00016 Kodiak 25-Aug-98 0.00132 Kodiak 29-Aug-01 0.00015 Kodiak 25-Aug-98 0.00132 Kodiak 29-Aug-01 0.00017 Kodiak 25-Aug-98 0.00131 Kodiak 18-Apr-02 0.00015 Kodiak 25-Aug-98 0.00134 Kodiak 18-Apr-02 0.00016 Kodiak 25-Aug-98 0.00132 Kodiak 18-Apr-02 0.00014 Kodiak 25-Aug-98 0.00132 Kodiak 18-Apr-02 0.00019 Kodiak 25-Aug-98 - Kodiak 18-Apr-02 0.00018 Kodiak 25-Aug-98 - Kodiak 18-Apr-02 0.00018 Kodiak 25-Aug-98 - Kodiak 18-Apr-02 0.00016 Kodiak 18-Apr-02 0.00014 Kodiak 4-Aug-07 0.000099 Kodiak 04-Jul-02 0.00017 Kodiak 4-Aug-07 0.000103 Kodiak 04-Jul-02 0.00018 Kodiak 4-Aug-07 0.000122 Kodiak 04-Jul-02 0.00017 Kodiak 4-Aug-07 0.000124 Kodiak 04-Jul-02 0.00014 Kodiak 4-Aug-07 0.000115 Kodiak 02-Aug-02 0.00019 Kodiak 4-Aug-07 0.000121 Kodiak 02-Aug-02 0.00018 Kodiak 26-Apr-07 0.00011 Kodiak 02-Aug-02 0.00019 Kodiak 26-Apr-07 0.000099 Kodiak 02-Aug-02 0.00019 Kodiak 26-Apr-07 0.000093 Kodiak 02-Sep-02 0.00018 Kodiak 26-Apr-07 0.000095 Kodiak 02-Sep-02 0.00019 Kodiak 9-Sep-07 0.000119 Kodiak 02-Sep-02 0.00019 Kodiak 9-Sep-07 0.000123 Kodiak 02-Sep-02 0.00018 Kodiak 6-May-08 0.000283 Kodiak 17-Apr-03 0.00011 Kodiak 6-May-08 0.000114 Kodiak 17-Apr-03 0.00011 Kodiak 6-May-08 0.000114 Kodiak 17-Apr-03 0.00013 Kodiak 6-May-08 0.000101 Kodiak 17-Apr-03 0.00012 Kodiak 13-Jul-08 0.00014 Kodiak 04-Jul-03 - Kodiak 13-Jul-08 0.000122 Kodiak 04-Jul-03 0.00013 Kodiak 27-Jul-08 0.000134 Kodiak 04-Jul-03 - Kodiak 27-Jul-08 0.000144 Kodiak 08-Aug-03 0.00015 Kodiak 27-Jul-08 0.000161 Kodiak 08-Aug-03 0.00015 Kodiak 27-Jul-08 0.000124 Kodiak 05-Sep-03 0.00018 Kodiak 27-Jul-08 0.000134 Kodiak 05-Sep-03 0.00017 Kodiak 27-Jul-08 0.000129 Kodiak 05-Sep-03 0.00018 Kodiak 6-Sep-08 0.000873 Kodiak 19-Apr-04 0.000116 Kodiak 6-Sep-08 0.000271 Kodiak 19-Apr-04 0.000119 Kodiak 2-May-09 0.00019 Kodiak 19-Apr-04 0.000087 Kodiak 2-May-09 0.000175 Kodiak 19-Apr-04 0.000089 Kodiak 2-May-09 0.00025 Kodiak 10-Jul-04 0.000129 Kodiak 2-May-09 0.000182 Kodiak 10-Jul-04 0.000112 Kodiak 11-Jul-09 0.000115 Page 7 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Kodiak 10-Jul-04 0.000156 Kodiak 11-Jul-09 0.000144 Kodiak 07-Aug-04 0.000127 Kodiak 8-Aug-09 0.000098 Kodiak 07-Aug-04 0.000136 Kodiak 8-Aug-09 0.000094 Kodiak 07-Sep-04 0.000108 Kodiak 8-Aug-09 0.000106 Kodiak 07-Sep-04 0.000118 Kodiak 8-Aug-09 0.000089 Kodiak 09-Jul-05 0.000082 Kodiak 8-Aug-09 0.000104 Kodiak 09-Jul-05 0.00009 Kodiak 8-Aug-09 0.000096 Kodiak 03-Aug-05 0.000128 Kodiak 4-Sep-09 0.000125 Kodiak 03-Aug-05 0.000113 Kodiak 4-Sep-09 0.000109 Kodiak 07-Sep-05 0.000112 Kodiak 5-Aug-10 0.000118 Kodiak 07-Sep-05 0.000106 Kodiak 5-Aug-10 0.000097 Kodiak 07-Sep-05 0.000103 Kodiak 5-Aug-10 0.000117 Kodiak 28-Apr-05 0.000138 Kodiak 5-Aug-10 0.000112 Kodiak 28-Apr-05 0.000128 Kodiak 16-Apr-10 0.000093 Kodiak 24-Apr-06 0.000102 Kodiak 16-Apr-10 0.000085 Kodiak 24-Apr-06 0.000085 Kodiak 16-Apr-10 0.0001 Kodiak 24-Apr-06 0.000088 Kodiak 16-Apr-10 0.000084 Kodiak 24-Apr-06 0.000083 Kodiak 5-Aug-11 0.000124 Kodiak 01-Jul-06 0.000118 Kodiak 5-Aug-11 0.000122 Kodiak 01-Jul-06 0.000119 Kodiak 5-Aug-11 0.000151 Kodiak 01-Aug-06 0.00014 Kodiak 5-Aug-11 0.000123 Kodiak 01-Aug-06 0.000125 Kodiak 5-Aug-11 0.000115 Kodiak 01-Aug-06 0.000116 Kodiak 5-Aug-11 0.000123 Kodiak 08-Sep-06 0.000178 Kodiak 28-Apr-11 0.000092 Kodiak 08-Sep-06 0.00024 Kodiak 28-Apr-11 0.000101 Kodiak 14-Jul-07 0.000145 Kodiak 28-Apr-11 0.000099 Kodiak 14-Jul-07 0.000116 Kodiak 28-Apr-11 0.000099 LdS1 01-Jul-00 <0.00006 LdS1 14-Jul-05 <0.00005 LdS1 01-Jul-00 <0.00006 LdS1 14-Jul-05 <0.00005 LdS1 01-Jul-00 <0.00006 LdS1 9-Aug-05 <0.00005 LdS1 02-Aug-00 <0.00006 LdS1 9-Aug-05 0.000051 LdS1 02-Aug-00 <0.00006 LdS1 1-Sep-05 0.000089 LdS1 02-Aug-00 <0.00006 LdS1 1-Sep-05 <0.00005 LdS1 02-Aug-00 <0.00006 LdS1 25-Apr-05 <0.000050 LdS1 03-Sep-00 <0.00006 LdS1 25-Apr-05 <0.000050 LdS1 03-Sep-00 <0.00006 LdS1 25-Apr-05 <0.000050 LdS1 03-Sep-00 <0.00006 LdS1 25-Apr-05 <0.000050 LdS1 03-Sep-00 <0.00006 LdS1 22-Apr-06 <0.000050 LdS1 06-Jul-01 <0.00006 LdS1 22-Apr-06 <0.000050 LdS1 06-Jul-01 <0.00006 LdS1 22-Apr-06 <0.000050 LdS1 06-Jul-01 <0.00006 LdS1 22-Apr-06 <0.000050 LdS1 06-Jul-01 <0.00006 LdS1 10-Jul-06 <0.000050 LdS1 31-Jul-01 <0.00006 LdS1 10-Jul-06 <0.000050 LdS1 31-Jul-01 <0.00006 LdS1 1-Aug-06 <0.000050 LdS1 31-Jul-01 <0.00006 LdS1 1-Aug-06 <0.000050 LdS1 31-Jul-01 <0.00006 LdS1 10-Sep-06 <0.000050 LdS1 03-Sep-01 <0.00006 LdS1 10-Sep-06 <0.000050 LdS1 03-Sep-01 <0.00006 LdS1 13-Jul-07 <0.000050 LdS1 03-Sep-01 <0.00006 LdS1 13-Jul-07 <0.000050 LdS1 03-Sep-01 <0.00006 LdS1 5-Aug-07 <0.000050 LdS1 09-Jul-02 <0.00006 LdS1 5-Aug-07 <0.000050 LdS1 09-Jul-02 <0.00006 LdS1 5-Aug-07 <0.000050 LdS1 09-Jul-02 <0.00006 LdS1 5-Aug-07 <0.000050 LdS1 09-Jul-02 <0.00006 LdS1 5-Aug-07 <0.000050 Page 8 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum LdS1 05-Aug-02 0.00009 LdS1 5-Aug-07 <0.000050 LdS1 05-Aug-02 <0.00006 LdS1 1-May-07 <0.000050 LdS1 05-Aug-02 <0.00006 LdS1 1-May-07 <0.000050 LdS1 05-Aug-02 <0.00006 LdS1 1-May-07 <0.000050 LdS1 06-Sep-02 <0.00006 LdS1 1-May-07 <0.000050 LdS1 06-Sep-02 <0.00006 LdS1 12-Sep-07 <0.000050 LdS1 06-Sep-02 <0.00006 LdS1 4-May-08 0.000057 LdS1 06-Sep-02 <0.00006 LdS1 4-May-08 0.000061 LdS1 23-Apr-02 <0.00006 LdS1 13-Jul-08 <0.000050 LdS1 23-Apr-02 <0.00006 LdS1 13-Jul-08 <0.000050 LdS1 23-Apr-02 <0.00006 LdS1 31-Jul-08 0.000199 LdS1 23-Apr-02 <0.00006 LdS1 31-Jul-08 0.000062 LdS1 07-Jul-03 <0.00006 LdS1 31-Jul-08 <0.000050 LdS1 07-Jul-03 <0.00006 LdS1 31-Jul-08 <0.000050 LdS1 06-Aug-03 <0.00006 LdS1 6-Sep-08 <0.000050 LdS1 10-Sep-03 <0.00006 LdS1 6-Sep-08 <0.000050 LdS1 10-Sep-03 <0.00006 LdS1 18-May-09 <0.000050 LdS1 13-Apr-03 <0.00006 LdS1 18-May-09 <0.000050 LdS1 13-Apr-03 <0.00006 LdS1 18-May-09 <0.000050 LdS1 13-Apr-03 <0.00006 LdS1 18-May-09 <0.000050 LdS1 13-Apr-03 <0.00006 LdS1 15-Jul-09 <0.000050 LdS1 12-Jul-04 <0.000050 LdS1 15-Jul-09 <0.000050 LdS1 13-Jul-04 <0.000050 LdS1 1-Aug-09 <0.000050 LdS1 10-Aug-04 <0.000050 LdS1 1-Aug-09 <0.000050 LdS1 10-Aug-04 <0.000050 LdS1 1-Aug-09 <0.000050 LdS1 09-Sep-04 <0.000050 LdS1 1-Aug-09 <0.000050 LdS1 09-Sep-04 <0.000050 LdS1 31-Jul-09 <0.000050 LdS1 17-Apr-04 <0.000050 LdS1 31-Jul-09 <0.000050 LdS1 17-Apr-04 <0.000050 LdS1 6-Sep-09 <0.000050 LdS1 17-Apr-04 <0.000050 LdS1 6-Sep-09 <0.000050 LdS1 17-Apr-04 <0.000050 LdS1 4-Aug-10 <0.000050 LdS1 04-Aug-10 <0.000050 LdS2 9-Aug-05 <0.00005 LdS1 04-Aug-10 <0.000050 LdS2 1-Sep-05 <0.00005 LdS1 04-Aug-10 <0.000050 LdS2 1-Sep-05 <0.00005 LdS1 04-Aug-10 <0.000050 LdS2 22-Apr-06 <0.000050 LdS1 04-Aug-10 <0.000050 LdS2 22-Apr-06 <0.000050 LdS1 14-Apr-10 <0.000050 LdS2 10-Jul-06 <0.000050 LdS1 14-Apr-10 <0.000050 LdS2 10-Jul-06 <0.000050 LdS1 14-Apr-10 <0.000050 LdS2 10-Jul-06 <0.000050 LdS1 14-Apr-10 <0.000050 LdS2 3-Aug-06 <0.000050 LdS1 04-Aug-11 <0.000050 LdS2 3-Aug-06 <0.000050 LdS1 04-Aug-11 <0.000050 LdS2 10-Sep-06 <0.000050 LdS1 04-Aug-11 <0.000050 LdS2 10-Sep-06 <0.000050 LdS1 04-Aug-11 <0.000050 LdS2 13-Jul-07 <0.000050 LdS1 04-Aug-11 <0.000050 LdS2 5-Aug-07 <0.000050 LdS1 04-Aug-11 <0.000050 LdS2 5-Aug-07 <0.000050 LdS1 26-Apr-11 <0.000050 LdS2 5-Aug-07 <0.000050 LdS1 26-Apr-11 <0.000050 LdS2 12-Sep-07 <0.000050 LdS1 26-Apr-11 <0.000050 LdS2 12-Sep-07 <0.000050 LdS1 26-Apr-11 <0.000050 LdS2 13-Jul-08 <0.000050 LdS2 01-Jul-00 <0.00006 LdS2 13-Jul-08 <0.000050 LdS2 01-Jul-00 <0.00006 LdS2 31-Jul-08 0.000277 LdS2 02-Aug-00 <0.00006 LdS2 31-Jul-08 0.000073 LdS2 02-Aug-00 <0.00006 LdS2 31-Jul-08 <0.000050 Page 9 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum LdS2 03-Sep-00 <0.00006 LdS2 5-Sep-08 <0.000050 LdS2 03-Sep-00 <0.00006 LdS2 5-Sep-08 <0.000050 LdS2 05-Jul-01 <0.00006 LdS2 15-Jul-09 <0.000050 LdS2 05-Jul-01 <0.00006 LdS2 15-Jul-09 <0.000050 LdS2 31-Jul-01 <0.00006 LdS2 1-Aug-09 <0.000050 LdS2 31-Jul-01 <0.00006 LdS2 1-Aug-09 <0.000050 LdS2 03-Sep-01 <0.00006 LdS2 1-Aug-09 <0.000050 LdS2 03-Sep-01 <0.00006 LdS2 6-Sep-09 <0.000050 LdS2 03-Sep-01 <0.00006 LdS2 6-Sep-09 <0.000050 LdS2 03-Sep-01 <0.00006 LdS2 4-Aug-10 <0.000050 LdS2 09-Jul-02 <0.00006 LdS2 4-Aug-10 <0.000050 LdS2 09-Jul-02 <0.00006 LdS2 4-Aug-10 <0.000050 LdS2 09-Jul-02 <0.00006 LdS2 4-Aug-11 <0.000050 LdS2 09-Jul-02 <0.00006 LdS2 4-Aug-11 <0.000050 LdS2 05-Aug-02 <0.00006 LdS2 4-Aug-11 <0.000050 LdS2 05-Aug-02 <0.00006 Leslie 21-Aug-94 <0.001 LdS2 06-Sep-02 <0.00006 Leslie 21-Aug-94 <0.001 LdS2 06-Sep-02 <0.00006 Leslie 21-Aug-94 <0.001 LdS2 06-Sep-02 <0.00006 Leslie - - LdS2 06-Sep-02 <0.00006 Leslie - - LdS2 07-Jul-03 <0.00006 Leslie - - LdS2 07-Jul-03 <0.00006 Leslie - - LdS2 06-Aug-03 <0.00006 Leslie 5-Jul-03 0.0101 LdS2 06-Aug-03 <0.00006 Leslie 5-Jul-03 0.0101 LdS2 10-Sep-03 <0.00006 Leslie 3-Aug-03 0.0123 LdS2 10-Sep-03 <0.00006 Leslie 3-Aug-03 0.012 LdS2 13-Jul-04 <0.000050 Leslie 9-Sep-03 0.0139 LdS2 13-Jul-04 <0.000050 Leslie 9-Sep-03 0.0139 LdS2 10-Aug-04 <0.000050 Leslie 15-Apr-03 0.0133 LdS2 10-Aug-04 <0.000050 Leslie 15-Apr-03 0.0108 LdS2 09-Sep-04 <0.000050 Leslie 15-Apr-03 0.0106 LdS2 09-Sep-04 <0.000050 Leslie 15-Apr-03 0.0113 LdS2 14-Jul-05 0.000145 Leslie 10-Jul-04 0.0256 LdS2 14-Jul-05 <0.00005 Leslie 10-Jul-04 0.026 LdS2 09-Aug-05 <0.00005 Leslie 10-Jul-04 0.0256 Leslie 09-Aug-04 0.0325 Leslie 2-May-09 0.0972 Leslie 09-Aug-04 0.0329 Leslie 2-May-09 0.095 Leslie 03-Sep-04 0.0295 Leslie 15-Jul-09 0.0594 Leslie 03-Sep-04 0.0301 Leslie 15-Jul-09 0.0615 Leslie 16-Apr-04 0.0488 Leslie 5-Aug-09 0.0624 Leslie 16-Apr-04 0.0504 Leslie 5-Aug-09 0.0587 Leslie 16-Apr-04 0.0455 Leslie 5-Aug-09 0.0637 Leslie 16-Apr-04 0.0459 Leslie 5-Aug-09 0.0608 Leslie 29-Apr-05 0.0617 Leslie 5-Aug-09 0.0566 Leslie 29-Apr-05 0.0615 Leslie 5-Aug-09 0.0617 Leslie 29-Apr-05 0.0603 Leslie 8-Sep-09 0.0787 Leslie 29-Apr-05 0.0606 Leslie 8-Sep-09 0.0781 Leslie 13-Jul-05 0.0563 Leslie 3-Aug-10 0.06 Leslie 13-Jul-05 0.0573 Leslie 3-Aug-10 0.0605 Leslie 13-Jul-05 0.0562 Leslie 3-Aug-10 0.0603 Leslie 04-Aug-05 0.0576 Leslie 3-Aug-10 0.0608 Leslie 04-Aug-05 0.0612 Leslie 3-Aug-10 0.0614 Leslie 04-Sep-05 0.0532 Leslie 3-Aug-10 0.0613 Leslie 04-Sep-05 0.0535 Leslie 17-Aug-10 - Page 10 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Leslie 23-Apr-06 0.0658 Leslie 31-Aug-10 - Leslie 23-Apr-06 0.0645 Leslie 17-Aug-10 - Leslie 23-Apr-06 0.0633 Leslie 31-Aug-10 - Leslie 23-Apr-06 0.0643 Leslie 16-Apr-10 0.0806 Leslie 02-Jul-06 0.0527 Leslie 16-Apr-10 0.0826 Leslie 02-Jul-06 0.0539 Leslie 16-Apr-10 0.0807 Leslie 06-Aug-06 0.0656 Leslie 16-Apr-10 0.0805 Leslie 06-Aug-06 0.0655 Leslie 2-Aug-11 0.07 Leslie 06-Sep-06 0.0609 Leslie 2-Aug-11 0.0709 Leslie 06-Sep-06 0.0641 Leslie 2-Aug-11 0.0707 Leslie 11-Jul-07 0.0607 Leslie 2-Aug-11 0.0702 Leslie 11-Jul-07 0.072 Leslie 2-Aug-11 0.0699 Leslie 13-Aug-07 0.0684 Leslie 2-Aug-11 0.0691 Leslie 13-Aug-07 0.0678 Leslie 27-Apr-11 0.088 Leslie 13-Aug-07 0.0693 Leslie 27-Apr-11 0.0865 Leslie 13-Aug-07 0.0675 Leslie 27-Apr-11 0.0916 Leslie 13-Aug-07 0.0686 Leslie 27-Apr-11 0.0888 Leslie 13-Aug-07 0.0706 Moose 6-Jul-94 <0.001 Leslie 26-Apr-07 0.103 Moose 6-Jul-94 <0.001 Leslie 26-Apr-07 0.0947 Moose 6-Jul-94 <0.001 Leslie 10-Sep-07 0.073 Moose 22-Aug-94 <0.001 Leslie 10-Sep-07 0.0708 Moose 22-Aug-94 <0.001 Leslie 10-Sep-07 0.0709 Moose 22-Aug-94 <0.001 Leslie 06-May-08 0.111 Moose 22-Aug-94 <0.001 Leslie 06-May-08 0.114 Moose 22-Aug-94 <0.001 Leslie 06-May-08 0.112 Moose 17-Apr-96 0.0001 Leslie 06-May-08 0.111 Moose 26-Jul-96 <0.00005 Leslie 08-Jul-08 0.0581 Moose 26-Jul-96 <0.00005 Leslie 08-Jul-08 0.0564 Moose 26-Jul-96 <0.00005 Leslie 31-Jul-08 0.0631 Moose 10-Aug-97 <0.00005 Leslie 31-Jul-08 0.063 Moose 10-Aug-97 0.00005 Leslie 31-Jul-08 0.0629 Moose 10-Aug-97 <0.00005 Leslie 31-Jul-08 0.0624 Moose 30-Jun-98 0.00026 Leslie 31-Jul-08 0.0668 Moose 30-Jun-98 0.00027 Leslie 31-Jul-08 0.0688 Moose 30-Jun-98 0.00027 Leslie 06-Sep-08 0.0567 Moose 30-Jun-98 0.00024 Leslie 06-Sep-08 0.057 Moose 30-Jun-98 0.00026 Leslie 02-May-09 0.0927 Moose 30-Jun-98 0.00026 Leslie 02-May-09 0.0937 Moose 15-Jul-98 0.00043 Moose 15-Jul-98 0.00044 Moose 3-Aug-01 0.00559 Moose 15-Jul-98 0.00042 Moose 3-Aug-01 0.00542 Moose 15-Jul-98 0.00043 Moose 3-Aug-01 0.0055 Moose 15-Jul-98 0.00044 Moose 5-Sep-01 0.00689 Moose 15-Jul-98 0.00043 Moose 5-Sep-01 0.00699 Moose 28-Jul-98 0.00012 Moose 5-Sep-01 0.00684 Moose 28-Jul-98 0.00013 Moose 5-Sep-01 0.00698 Moose 28-Jul-98 0.00012 Moose 6-Jul-02 0.00437 Moose 28-Jul-98 0.00011 Moose 6-Jul-02 0.00435 Moose 28-Jul-98 0.00012 Moose 6-Jul-02 0.0046 Moose 28-Jul-98 0.00012 Moose 6-Jul-02 0.00461 Moose 11-Aug-98 0.00008 Moose 5-Aug-02 0.00867 Moose 11-Aug-98 0.00009 Moose 5-Aug-02 0.00886 Moose 11-Aug-98 0.00008 Moose 5-Aug-02 0.00853 Moose 11-Aug-98 0.00008 Moose 5-Aug-02 0.00872 Page 11 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Moose 11-Aug-98 0.00008 Moose 8-Sep-02 0.0106 Moose 11-Aug-98 0.00007 Moose 8-Sep-02 0.0107 Moose 03-Sep-98 0.00007 Moose 8-Sep-02 0.0108 Moose 03-Sep-98 0.00006 Moose 8-Sep-02 0.0105 Moose 03-Sep-98 0.00007 Moose 20-Apr-02 0.0122 Moose 03-Sep-98 0.00008 Moose 20-Apr-02 0.0121 Moose 03-Sep-98 0.00007 Moose 20-Apr-02 0.0118 Moose 03-Sep-98 0.00007 Moose 20-Apr-02 0.0115 Moose 08-Jul-99 - Moose 15-Apr-03 0.0114 Moose 08-Jul-99 - Moose 15-Apr-03 0.0107 Moose 08-Jul-99 - Moose 15-Apr-03 0.0108 Moose 08-Jul-99 - Moose 3-Jul-03 0.00887 Moose 08-Jul-99 - Moose 3-Jul-03 0.00842 Moose 08-Jul-99 - Moose 9-Aug-03 0.0109 Moose 07-Aug-99 - Moose 9-Aug-03 0.0108 Moose 07-Aug-99 - Moose 9-Aug-03 0.0109 Moose 07-Aug-99 - Moose 8-Sep-03 0.0127 Moose 07-Aug-99 - Moose 8-Sep-03 0.0128 Moose 07-Aug-99 - Moose 15-Apr-03 0.0121 Moose 07-Aug-99 - Moose 16-Apr-04 0.0577 Moose 03-Sep-99 - Moose 16-Apr-04 0.0583 Moose 03-Sep-99 - Moose 16-Apr-04 0.0565 Moose 03-Sep-99 - Moose 16-Apr-04 0.0561 Moose 03-Sep-99 - Moose 9-Jul-04 0.0215 Moose 03-Sep-99 - Moose 9-Jul-04 0.0201 Moose 03-Sep-99 - Moose 10-Aug-04 0.0305 Moose 28-Jun-00 0.00111 Moose 10-Aug-04 0.0297 Moose 28-Jun-00 0.00111 Moose 10-Aug-04 0.0296 Moose 28-Jun-00 0.00099 Moose 2-Sep-04 0.0279 Moose 28-Jun-00 0.00106 Moose 2-Sep-04 0.0286 Moose 30-Jul-00 0.00214 Moose 11-Jul-05 0.0431 Moose 30-Jul-00 0.00215 Moose 11-Jul-05 0.0443 Moose 30-Jul-00 0.00213 Moose 11-Jul-05 0.0446 Moose 30-Jul-00 0.00214 Moose 9-Aug-05 0.0308 Moose 31-Aug-00 0.00311 Moose 9-Aug-05 0.0317 Moose 31-Aug-00 0.00307 Moose 5-Sep-05 0.0223 Moose 31-Aug-00 0.00316 Moose 5-Sep-05 0.0226 Moose 31-Aug-00 0.00312 Moose 26-Apr-05 0.0613 Moose 02-Jul-01 0.00402 Moose 26-Apr-05 0.0563 Moose 02-Jul-01 0.004 Moose 26-Apr-05 0.062 Moose 02-Jul-01 0.00397 Moose 26-Apr-05 0.0605 Moose 02-Jul-01 0.00402 Moose 23-Apr-06 0.0629 Moose 03-Aug-01 0.00557 Moose 23-Apr-06 0.0618 Moose 23-Apr-06 0.0624 Moose 3-Aug-10 0.0586 Moose 23-Apr-06 0.0625 Moose 17-Aug-10 - Moose 01-Jul-06 0.0521 Moose 31-Aug-10 - Moose 02-Jul-06 0.0506 Moose 17-Aug-10 - Moose 02-Jul-06 0.0496 Moose 31-Aug-10 - Moose 05-Aug-06 0.0613 Moose 14-Apr-10 0.0837 Moose 05-Aug-06 0.0612 Moose 14-Apr-10 0.0794 Moose 07-Sep-06 0.0596 Moose 14-Apr-10 0.0827 Moose 07-Sep-06 0.0577 Moose 14-Apr-10 0.0837 Moose 07-Sep-06 0.0595 Moose 3-Aug-11 0.0686 Moose 15-Jul-07 0.0568 Moose 3-Aug-11 0.0689 Page 12 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Moose 15-Jul-07 0.0647 Moose 3-Aug-11 0.0681 Moose 07-Aug-07 0.0703 Moose 3-Aug-11 0.068 Moose 07-Aug-07 0.0717 Moose 3-Aug-11 0.0685 Moose 07-Aug-07 0.0716 Moose 3-Aug-11 0.0675 Moose 07-Aug-07 0.0707 Moose 27-Apr-11 0.0866 Moose 07-Aug-07 0.0691 Moose 27-Apr-11 0.0857 Moose 07-Aug-07 0.0699 Moose 27-Apr-11 0.0813 Moose 27-Apr-07 0.0906 Moose 27-Apr-11 0.0811 Moose 27-Apr-07 0.0892 Mosee East 27-Apr-11 0.106 Moose 27-Apr-07 0.0937 Mosee East 27-Apr-11 0.106 Moose 27-Apr-07 0.09 Nanuq 4-Aug-97 <0.00005 Moose 10-Sep-07 0.0687 Nanuq 4-Aug-97 <0.00005 Moose 10-Sep-07 0.0695 Nanuq 4-Aug-97 <0.00005 Moose 06-May-08 0.11 Nanuq 4-Aug-97 <0.00005 Moose 06-May-08 0.112 Nanuq 4-Aug-97 <0.00005 Moose 06-May-08 0.113 Nanuq 4-Aug-97 <0.00005 Moose 06-May-08 0.111 Nanuq 4-Aug-97 <0.00005 Moose 13-Jul-08 0.0303 Nanuq 4-Aug-97 <0.00005 Moose 13-Jul-08 0.03 Nanuq 4-Aug-97 <0.00005 Moose 29-Jul-08 0.0336 Nanuq 30-Jun-98 <0.00006 Moose 29-Jul-08 0.0319 Nanuq 30-Jun-98 <0.00006 Moose 29-Jul-08 0.0325 Nanuq 30-Jun-98 <0.00006 Moose 29-Jul-08 0.0338 Nanuq 30-Jun-98 <0.00006 Moose 29-Jul-08 0.0329 Nanuq 30-Jun-98 <0.00006 Moose 29-Jul-08 0.0351 Nanuq 30-Jun-98 <0.00006 Moose 09-Sep-08 0.0512 Nanuq 15-Jul-98 <0.00006 Moose 09-Sep-08 0.051 Nanuq 15-Jul-98 <0.00006 Moose 09-Sep-08 0.0516 Nanuq 15-Jul-98 <0.00006 Moose 29-Apr-09 0.0866 Nanuq 15-Jul-98 <0.00006 Moose 29-Apr-09 0.0883 Nanuq 15-Jul-98 <0.00006 Moose 29-Apr-09 0.0874 Nanuq 15-Jul-98 <0.00006 Moose 29-Apr-09 0.0847 Nanuq 29-Jul-98 <0.00006 Moose 14-Jul-09 0.0299 Nanuq 29-Jul-98 <0.00006 Moose 14-Jul-09 0.0315 Nanuq 29-Jul-98 <0.00006 Moose 30-Jul-09 0.0533 Nanuq 29-Jul-98 <0.00006 Moose 30-Jul-09 0.0558 Nanuq 29-Jul-98 <0.00006 Moose 30-Jul-09 0.0566 Nanuq 29-Jul-98 <0.00006 Moose 30-Jul-09 0.0559 Nanuq 11-Aug-98 <0.00006 Moose 30-Jul-09 0.0546 Nanuq 11-Aug-98 <0.00006 Moose 30-Jul-09 0.0548 Nanuq 11-Aug-98 <0.00006 Moose 07-Sep-09 0.0597 Nanuq 11-Aug-98 <0.00006 Moose 07-Sep-09 0.0603 Nanuq 11-Aug-98 <0.00006 Moose 03-Aug-10 0.0563 Nanuq 11-Aug-98 <0.00006 Moose 03-Aug-10 0.0569 Nanuq 9-Sep-98 <0.00006 Moose 03-Aug-10 0.0584 Nanuq 9-Sep-98 <0.00006 Moose 03-Aug-10 0.0582 Nanuq 9-Sep-98 <0.00006 Moose 03-Aug-10 0.0585 Nanuq 9-Sep-98 <0.00006 Nanuq 09-Sep-98 <0.00006 Nanuq 19-Apr-02 <0.00006 Nanuq 09-Sep-98 <0.00006 Nanuq 19-Apr-02 <0.00006 Nanuq 09-Jul-99 - Nanuq 6-Jul-03 <0.00006 Nanuq 09-Jul-99 - Nanuq 6-Jul-03 <0.00006 Nanuq 09-Jul-99 - Nanuq 9-Aug-03 <0.00006 Nanuq 09-Jul-99 - Nanuq 9-Aug-03 <0.00006 Nanuq 09-Jul-99 - Nanuq 9-Aug-03 <0.00006 Page 13 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Nanuq 09-Jul-99 - Nanuq 7-Sep-03 <0.00006 Nanuq 07-Aug-99 - Nanuq 7-Sep-03 <0.00006 Nanuq 07-Aug-99 - Nanuq 12-Apr-03 <0.00006 Nanuq 07-Aug-99 - Nanuq 12-Apr-03 <0.00006 Nanuq 07-Aug-99 - Nanuq 12-Apr-03 <0.00006 Nanuq 07-Aug-99 - Nanuq 12-Apr-03 <0.00006 Nanuq 07-Aug-99 - Nanuq 13-Jul-04 <0.000050 Nanuq 04-Sep-99 - Nanuq 13-Jul-04 <0.000050 Nanuq 04-Sep-99 - Nanuq 10-Aug-04 <0.000050 Nanuq 04-Sep-99 - Nanuq 10-Aug-04 <0.000050 Nanuq 04-Sep-99 - Nanuq 10-Aug-04 <0.000050 Nanuq 04-Sep-99 - Nanuq 12-Sep-04 <0.000050 Nanuq 04-Sep-99 - Nanuq 12-Sep-04 <0.000050 Nanuq 03-Jul-00 <0.00006 Nanuq 18-Apr-04 <0.000050 Nanuq 03-Jul-00 <0.00006 Nanuq 18-Apr-04 <0.000050 Nanuq 03-Jul-00 <0.00006 Nanuq 18-Apr-04 <0.000050 Nanuq 03-Jul-00 <0.00006 Nanuq 18-Apr-04 <0.000050 Nanuq 04-Aug-00 <0.00006 Nanuq 14-Jul-05 <0.00005 Nanuq 04-Aug-00 <0.00006 Nanuq 14-Jul-05 <0.00005 Nanuq 04-Aug-00 <0.00006 Nanuq 1-Aug-05 <0.00005 Nanuq 04-Aug-00 <0.00006 Nanuq 1-Aug-05 <0.00005 Nanuq 05-Sep-00 <0.00006 Nanuq 1-Sep-05 <0.00005 Nanuq 05-Sep-00 <0.00006 Nanuq 1-Sep-05 <0.00005 Nanuq 05-Sep-00 <0.00006 Nanuq 1-Sep-05 <0.00005 Nanuq 05-Sep-00 0.00006 Nanuq 24-Apr-05 <0.000050 Nanuq 07-Jul-01 <0.00006 Nanuq 24-Apr-05 <0.000050 Nanuq 07-Jul-01 <0.00006 Nanuq 24-Apr-05 <0.000050 Nanuq 07-Jul-01 <0.00006 Nanuq 24-Apr-05 <0.000050 Nanuq 07-Jul-01 <0.00006 Nanuq 20-Apr-06 <0.000050 Nanuq 01-Aug-01 <0.00006 Nanuq 20-Apr-06 <0.000050 Nanuq 01-Aug-01 <0.00006 Nanuq 20-Apr-06 <0.000050 Nanuq 01-Aug-01 <0.00006 Nanuq 20-Apr-06 <0.000050 Nanuq 01-Aug-01 <0.00006 Nanuq 29-Jun-06 <0.000050 Nanuq 01-Sep-01 <0.00006 Nanuq 29-Jun-06 0.000105 Nanuq 01-Sep-01 <0.00006 Nanuq 2-Aug-06 <0.000050 Nanuq 01-Sep-01 <0.00006 Nanuq 2-Aug-06 <0.000050 Nanuq 01-Sep-01 <0.00006 Nanuq 2-Aug-06 <0.000050 Nanuq 10-Jul-02 <0.00006 Nanuq 5-Sep-06 <0.000050 Nanuq 10-Jul-02 <0.00006 Nanuq 5-Sep-06 <0.000050 Nanuq 10-Jul-02 <0.00006 Nanuq 15-Jul-07 <0.000050 Nanuq 10-Jul-02 <0.00006 Nanuq 15-Jul-07 0.000067 Nanuq 01-Aug-02 <0.00006 Nanuq 11-Aug-07 <0.000050 Nanuq 01-Aug-02 <0.00006 Nanuq 11-Aug-07 <0.000050 Nanuq 01-Aug-02 <0.00006 Nanuq 11-Aug-07 <0.000050 Nanuq 01-Aug-02 <0.00006 Nanuq 11-Aug-07 <0.000050 Nanuq 01-Sep-02 <0.00006 Nanuq 11-Aug-07 <0.000050 Nanuq 01-Sep-02 <0.00006 Nanuq 11-Aug-07 <0.000050 Nanuq 01-Sep-02 <0.00006 Nanuq 21-Apr-07 <0.000050 Nanuq 01-Sep-02 <0.00006 Nanuq 21-Apr-07 <0.000050 Nanuq 19-Apr-02 <0.00006 Nanuq 21-Apr-07 <0.000050 Nanuq 19-Apr-02 <0.00006 Nanuq 21-Apr-07 <0.000050 Nanuq 11-Sep-07 0.000103 Nema 11-Aug-95 <0.001 Nanuq 11-Sep-07 <0.000050 Nema 11-Aug-95 <0.001 Nanuq 27-Apr-08 <0.000050 Nema 17-Apr-96 0.0002 Page 14 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Nanuq 27-Apr-08 <0.000050 Nema 26-Jul-96 0.00009 Nanuq 27-Apr-08 <0.000050 Nema 26-Jul-96 0.00009 Nanuq 27-Apr-08 <0.000050 Nema 26-Jul-96 0.00009 Nanuq 07-Jul-08 <0.000050 Nema 11-Aug-97 0.00007 Nanuq 07-Jul-08 <0.000050 Nema 11-Aug-97 0.00006 Nanuq 08-Aug-08 <0.000050 Nema 11-Aug-97 0.00005 Nanuq 08-Aug-08 <0.000050 Nema 30-Jun-98 0.00039 Nanuq 08-Aug-08 <0.000050 Nema 30-Jun-98 0.00038 Nanuq 08-Aug-08 <0.000050 Nema 30-Jun-98 0.00039 Nanuq 08-Aug-08 <0.000050 Nema 30-Jun-98 0.00037 Nanuq 08-Aug-08 <0.000050 Nema 30-Jun-98 0.00036 Nanuq 09-Sep-08 <0.000050 Nema 30-Jun-98 0.00037 Nanuq 09-Sep-08 <0.000050 Nema 17-Jul-98 0.00033 Nanuq 11-May-09 <0.000050 Nema 17-Jul-98 0.00034 Nanuq 11-May-09 <0.000050 Nema 17-Jul-98 0.00034 Nanuq 11-May-09 <0.000050 Nema 17-Jul-98 0.00033 Nanuq 11-May-09 <0.000050 Nema 17-Jul-98 0.00033 Nanuq 18-May-09 <0.000050 Nema 17-Jul-98 0.00034 Nanuq 18-May-09 <0.000050 Nema 28-Jul-98 0.00034 Nanuq 18-May-09 <0.000050 Nema 28-Jul-98 0.00035 Nanuq 18-May-09 <0.000050 Nema 28-Jul-98 0.00035 Nanuq 13-Jul-09 <0.000050 Nema 28-Jul-98 0.00034 Nanuq 13-Jul-09 <0.000050 Nema 28-Jul-98 0.00034 Nanuq 13-Jul-09 <0.000050 Nema 28-Jul-98 0.00036 Nanuq 30-Jul-09 <0.000050 Nema 11-Aug-98 0.00028 Nanuq 30-Jul-09 <0.000050 Nema 11-Aug-98 0.00031 Nanuq 30-Jul-09 <0.000050 Nema 11-Aug-98 0.0003 Nanuq 30-Jul-09 <0.000050 Nema 11-Aug-98 0.00031 Nanuq 30-Jul-09 <0.000050 Nema 11-Aug-98 0.00031 Nanuq 30-Jul-09 <0.000050 Nema 11-Aug-98 0.0003 Nanuq 08-Sep-09 <0.000050 Nema 3-Sep-98 0.00023 Nanuq 08-Sep-09 <0.000050 Nema 3-Sep-98 0.00023 Nanuq 06-Aug-10 <0.000050 Nema 3-Sep-98 0.00024 Nanuq 06-Aug-10 <0.000050 Nema 3-Sep-98 0.00024 Nanuq 06-Aug-10 <0.000050 Nema 3-Sep-98 0.00025 Nanuq 05-Aug-10 <0.000050 Nema 3-Sep-98 0.00024 Nanuq 05-Aug-10 <0.000050 Nema 10-Jul-99 - Nanuq 05-Aug-10 <0.000050 Nema 10-Jul-99 - Nanuq 14-Apr-10 <0.000050 Nema 10-Jul-99 - Nanuq 14-Apr-10 <0.000050 Nema 10-Jul-99 - Nanuq 14-Apr-10 <0.000050 Nema 10-Jul-99 - Nanuq 14-Apr-10 <0.000050 Nema 10-Jul-99 - Nanuq 02-Aug-11 <0.000050 Nema 10-Aug-99 - Nanuq 02-Aug-11 <0.000050 Nema 10-Aug-99 - Nanuq 02-Aug-11 <0.000050 Nema 10-Aug-99 - Nanuq 02-Aug-11 <0.000050 Nema 10-Aug-99 - Nanuq 02-Aug-11 <0.000050 Nema 10-Aug-99 - Nanuq 02-Aug-11 <0.000050 Nema 10-Aug-99 - Nanuq 25-Apr-11 <0.000050 Nema 7-Sep-99 - Nanuq 25-Apr-11 <0.000050 Nema 7-Sep-99 - Nanuq 25-Apr-11 <0.000050 Nema 7-Sep-99 - Nanuq 25-Apr-11 <0.000050 Nema 7-Sep-99 - Nema 11-Aug-95 <0.001 Nema 7-Sep-99 - Nema 11-Aug-95 <0.001 Nema 7-Sep-99 - Page 15 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Nema 11-Aug-95 <0.001 Nema 29-Jun-00 0.00024 Nema 29-Jun-00 0.00023 Nema 17-Apr-04 0.00496 Nema 29-Jun-00 0.00022 Nema 25-Apr-05 0.0175 Nema 29-Jun-00 0.00022 Nema 25-Apr-05 0.0173 Nema 30-Jul-00 0.00037 Nema 25-Apr-05 0.0184 Nema 30-Jul-00 0.00036 Nema 25-Apr-05 0.0188 Nema 30-Jul-00 0.00036 Nema 11-Jul-05 0.02 Nema 30-Jul-00 0.00038 Nema 11-Jul-05 0.0201 Nema 01-Sep-00 0.0005 Nema 9-Aug-05 0.021 Nema 01-Sep-00 0.0005 Nema 9-Aug-05 0.0202 Nema 01-Sep-00 0.0005 Nema 1-Sep-05 0.0193 Nema 01-Sep-00 0.0005 Nema 1-Sep-05 0.0193 Nema 03-Jul-01 0.00046 Nema 23-Apr-06 0.0115 Nema 03-Jul-01 0.00047 Nema 23-Apr-06 0.0117 Nema 03-Jul-01 0.00046 Nema 23-Apr-06 0.013 Nema 03-Aug-01 0.00105 Nema 23-Apr-06 0.0128 Nema 03-Aug-01 0.00105 Nema 2-Jul-06 0.00766 Nema 03-Aug-01 0.00107 Nema 2-Jul-06 0.00764 Nema 03-Aug-01 0.00104 Nema 5-Aug-06 0.0207 Nema 05-Sep-01 0.0024 Nema 5-Aug-06 0.0193 Nema 05-Sep-01 0.00238 Nema 7-Sep-06 0.0199 Nema 05-Sep-01 0.00239 Nema 7-Sep-06 0.0195 Nema 05-Sep-01 0.00236 Nema 7-Sep-06 0.0195 Nema 18-Apr-02 0.00176 Nema 14-Jul-07 0.0146 Nema 18-Apr-02 0.00169 Nema 14-Jul-07 0.0148 Nema 18-Apr-02 0.00172 Nema 14-Jul-07 0.0146 Nema 18-Apr-02 0.00171 Nema 11-Aug-07 0.0219 Nema 06-Jul-02 0.0018 Nema 11-Aug-07 0.0232 Nema 06-Jul-02 0.00181 Nema 11-Aug-07 0.0229 Nema 06-Jul-02 0.0018 Nema 11-Aug-07 0.0223 Nema 06-Jul-02 0.00175 Nema 11-Aug-07 0.0228 Nema 04-Aug-02 0.00182 Nema 11-Aug-07 0.0223 Nema 04-Aug-02 0.00181 Nema 27-Apr-07 0.0315 Nema 04-Aug-02 0.00184 Nema 27-Apr-07 0.0308 Nema 04-Aug-02 0.00184 Nema 27-Apr-07 0.031 Nema 07-Sep-02 0.00182 Nema 27-Apr-07 0.032 Nema 07-Sep-02 0.00187 Nema 10-Sep-07 0.0257 Nema 07-Sep-02 0.00209 Nema 10-Sep-07 0.0257 Nema 07-Sep-02 0.00205 Nema 6-May-08 0.0471 Nema 14-Apr-03 0.00191 Nema 6-May-08 0.0465 Nema 14-Apr-03 0.00164 Nema 6-May-08 0.0465 Nema 14-Apr-03 0.00169 Nema 6-May-08 0.0469 Nema 14-Apr-03 0.00154 Nema 9-Jul-08 0.0227 Nema 05-Jul-03 0.00141 Nema 9-Jul-08 0.0236 Nema 05-Jul-03 0.00143 Nema 29-Jul-08 0.0249 Nema 03-Aug-03 0.00181 Nema 29-Jul-08 0.0252 Nema 03-Aug-03 0.00176 Nema 29-Jul-08 0.025 Nema 08-Sep-03 0.00173 Nema 29-Jul-08 0.0245 Nema 08-Sep-03 0.00178 Nema 29-Jul-08 0.0249 Nema 08-Sep-03 0.00175 Nema 29-Jul-08 0.025 Nema 12-Jul-04 0.00505 Nema 6-Sep-08 0.0201 Nema 12-Jul-04 0.00542 Nema 6-Sep-08 0.0201 Nema 09-Aug-04 0.00897 Nema 29-Apr-09 0.0176 Nema 09-Aug-04 0.00912 Nema 29-Apr-09 0.0176 Page 16 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Nema 09-Sep-04 0.00936 Nema 29-Apr-09 0.0172 Nema 09-Sep-04 0.00907 Nema 29-Apr-09 0.0174 Nema 17-Apr-04 0.005 Nema 3-Jul-09 0.00877 Nema 17-Apr-04 0.00502 Nema 3-Jul-09 0.00892 Nema 17-Apr-04 0.00505 Nema 30-Jul-09 0.0161 Nema 30-Jul-09 0.0155 S2 3-Sep-98 <0.00006 Nema 30-Jul-09 0.0152 S2 3-Sep-98 <0.00006 Nema 30-Jul-09 0.0149 S2 13-Jul-99 - Nema 30-Jul-09 0.0154 S2 13-Jul-99 - Nema 30-Jul-09 0.0149 S2 13-Jul-99 - Nema 07-Sep-09 0.0173 S2 13-Jul-99 - Nema 07-Sep-09 0.0172 S2 13-Jul-99 - Nema 05-Aug-10 0.0158 S2 13-Jul-99 - Nema 05-Aug-10 0.0159 S2 11-Aug-99 - Nema 05-Aug-10 0.0157 S2 11-Aug-99 - Nema 05-Aug-10 0.0157 S2 11-Aug-99 - Nema 05-Aug-10 0.0157 S2 11-Aug-99 - Nema 05-Aug-10 0.0155 S2 11-Aug-99 - Nema 15-Apr-10 0.0173 S2 11-Aug-99 - Nema 15-Apr-10 0.0171 S2 8-Sep-99 - Nema 15-Apr-10 0.0184 S2 8-Sep-99 - Nema 15-Apr-10 0.0174 S2 8-Sep-99 - Nema 05-Aug-11 0.0199 S2 8-Sep-99 - Nema 05-Aug-11 0.0203 S2 8-Sep-99 - Nema 05-Aug-11 0.0201 S2 8-Sep-99 - Nema 05-Aug-11 0.0205 S2 2-Jul-00 <0.00006 Nema 05-Aug-11 0.0205 S2 2-Jul-00 <0.00006 Nema 05-Aug-11 0.0204 S2 2-Jul-00 <0.00006 Nema 27-Apr-11 0.0255 S2 2-Jul-00 <0.00006 Nema 27-Apr-11 0.0252 S2 3-Aug-00 <0.00006 Nema 27-Apr-11 0.0244 S2 3-Aug-00 <0.00006 Nema 27-Apr-11 0.0244 S2 3-Aug-00 <0.00006 S2 07-Jul-94 <0.001 S2 3-Aug-00 <0.00006 S2 14-Aug-94 <0.001 S2 2-Sep-00 <0.00006 S2 12-Aug-97 <0.00005 S2 2-Sep-00 <0.00006 S2 02-Jul-98 <0.00006 S2 2-Sep-00 <0.00006 S2 02-Jul-98 <0.00006 S2 2-Sep-00 <0.00006 S2 02-Jul-98 <0.00006 S2 4-Jul-01 0.0001 S2 02-Jul-98 <0.00006 S2 4-Jul-01 0.0001 S2 02-Jul-98 <0.00006 S2 4-Jul-01 0.0001 S2 02-Jul-98 <0.00006 S2 4-Jul-01 0.0001 S2 16-Jul-98 <0.00006 S2 29-Jul-01 <0.00006 S2 16-Jul-98 <0.00006 S2 29-Jul-01 <0.00006 S2 16-Jul-98 <0.00006 S2 29-Jul-01 <0.00006 S2 16-Jul-98 <0.00006 S2 29-Jul-01 <0.00006 S2 16-Jul-98 <0.00006 S2 31-Aug-01 <0.00006 S2 16-Jul-98 <0.00006 S2 31-Aug-01 <0.00006 S2 30-Jul-98 <0.00006 S2 31-Aug-01 <0.00006 S2 30-Jul-98 <0.00006 S2 31-Aug-01 <0.00006 S2 30-Jul-98 <0.00006 S2 23-Apr-02 <0.00006 S2 30-Jul-98 <0.00006 S2 23-Apr-02 <0.00006 S2 30-Jul-98 <0.00006 S2 23-Apr-02 0.00007 S2 30-Jul-98 <0.00006 S2 23-Apr-02 0.00009 S2 13-Aug-98 <0.00006 S2 7-Jul-02 0.00009 Page 17 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum S2 13-Aug-98 <0.00006 S2 7-Jul-02 0.00008 S2 13-Aug-98 <0.00006 S2 7-Jul-02 0.00008 S2 13-Aug-98 <0.00006 S2 7-Jul-02 0.00008 S2 13-Aug-98 <0.00006 S2 4-Aug-02 <0.00006 S2 13-Aug-98 <0.00006 S2 4-Aug-02 <0.00006 S2 03-Sep-98 <0.00006 S2 4-Aug-02 <0.00006 S2 03-Sep-98 <0.00006 S2 4-Aug-02 <0.00006 S2 03-Sep-98 <0.00006 S2 3-Sep-02 0.00016 S2 03-Sep-98 <0.00006 S2 3-Sep-02 0.00015 S2 03-Sep-02 0.00018 S2 4-May-08 0.000137 S2 03-Sep-02 0.00017 S2 4-May-08 0.000108 S2 15-Apr-03 <0.00006 S2 13-Jul-08 0.00158 S2 15-Apr-03 <0.00006 S2 13-Jul-08 0.00152 S2 15-Apr-03 <0.00006 S2 7-Aug-08 0.00058 S2 15-Apr-03 0.00006 S2 7-Aug-08 0.000591 S2 03-Jul-03 0.00009 S2 7-Aug-08 0.000572 S2 03-Jul-03 0.0001 S2 7-Aug-08 0.000566 S2 05-Aug-03 0.0001 S2 7-Aug-08 0.000597 S2 05-Aug-03 0.00009 S2 7-Aug-08 0.000581 S2 03-Sep-03 0.0001 S2 5-Sep-08 0.00176 S2 03-Sep-03 0.00011 S2 5-Sep-08 0.00157 S2 12-Jul-04 0.000939 S2 18-May-09 0.00022 S2 12-Jul-04 0.000939 S2 18-May-09 0.000211 S2 09-Aug-04 0.000633 S2 18-May-09 0.000275 S2 09-Aug-04 0.000573 S2 18-May-09 0.00024 S2 13-Sep-04 0.000432 S2 13-Jul-09 0.00277 S2 13-Sep-04 0.000408 S2 13-Jul-09 0.00229 S2 13-Sep-04 0.000396 S2 31-Jul-09 0.00122 S2 17-Apr-04 <0.000050 S2 31-Jul-09 0.00111 S2 17-Apr-04 <0.000050 S2 31-Jul-09 0.00112 S2 26-Apr-05 0.000116 S2 31-Jul-09 0.0012 S2 26-Apr-05 0.000125 S2 31-Jul-09 0.00093 S2 11-Jul-05 0.00145 S2 31-Jul-09 0.000923 S2 11-Jul-05 0.0014 S2 6-Sep-09 0.00084 S2 11-Jul-05 0.0015 S2 6-Sep-09 0.000825 S2 05-Aug-05 0.000749 S2 6-Aug-10 0.001 S2 05-Aug-05 0.000667 S2 6-Aug-10 0.000928 S2 31-Aug-05 0.000783 S2 6-Aug-10 0.000948 S2 31-Aug-05 0.000867 S2 6-Aug-10 0.000971 S2 18-Apr-06 0.000079 S2 6-Aug-10 0.000946 S2 18-Apr-06 0.00007 S2 5-Aug-10 0.001 S2 18-Apr-06 0.000091 S2 15-Apr-10 0.000157 S2 18-Apr-06 0.000065 S2 15-Apr-10 0.000136 S2 01-Jul-06 0.00135 S2 15-Apr-10 0.000166 S2 01-Jul-06 0.00119 S2 15-Apr-10 0.000124 S2 04-Aug-06 0.00285 S2 4-Aug-11 0.000886 S2 04-Aug-06 0.00275 S2 4-Aug-11 0.00117 S2 04-Aug-06 0.00096 S2 4-Aug-11 0.00128 S2 06-Sep-06 0.000552 S2 4-Aug-11 0.00119 S2 06-Sep-06 0.000587 S2 4-Aug-11 0.000773 S2 13-Jul-07 0.00149 S2 4-Aug-11 0.000876 S2 13-Jul-07 0.00124 S2 27-Apr-11 0.000303 S2 08-Aug-07 0.000785 S2 27-Apr-11 0.000313 S2 08-Aug-07 0.00084 S2 27-Apr-11 0.000387 Page 18 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum S2 08-Aug-07 0.000753 S2 27-Apr-11 0.000377 S2 08-Aug-07 0.000684 S3 7-Jul-94 <0.001 S2 08-Aug-07 0.000679 S3 14-Aug-94 <0.001 S2 08-Aug-07 0.000687 S3 12-Aug-97 <0.00005 S2 23-Apr-07 0.000129 S3 12-Aug-97 <0.00005 S2 23-Apr-07 0.000127 S3 12-Aug-97 <0.00005 S2 23-Apr-07 0.000105 S3 2-Jul-98 <0.00006 S2 23-Apr-07 0.000111 S3 2-Jul-98 <0.00006 S2 13-Sep-07 0.000795 S3 2-Jul-98 <0.00006 S2 13-Sep-07 0.000825 S3 2-Jul-98 <0.00006 S2 13-Sep-07 0.000785 S3 2-Jul-98 <0.00006 S2 04-May-08 0.000091 S3 2-Jul-98 <0.00006 S2 04-May-08 0.000103 S3 16-Jul-98 <0.00006 S3 16-Jul-98 <0.00006 S3 29-Jul-01 <0.00006 S3 16-Jul-98 <0.00006 S3 29-Jul-01 <0.00006 S3 16-Jul-98 <0.00006 S3 29-Jul-01 <0.00006 S3 16-Jul-98 <0.00006 S3 31-Aug-01 <0.00006 S3 16-Jul-98 <0.00006 S3 31-Aug-01 <0.00006 S3 30-Jul-98 <0.00006 S3 31-Aug-01 <0.00006 S3 30-Jul-98 <0.00006 S3 31-Aug-01 <0.00006 S3 30-Jul-98 <0.00006 S3 7-Jul-02 <0.00006 S3 30-Jul-98 <0.00006 S3 7-Jul-02 <0.00006 S3 30-Jul-98 <0.00006 S3 7-Jul-02 <0.00006 S3 30-Jul-98 <0.00006 S3 7-Jul-02 <0.00006 S3 13-Aug-98 <0.00006 S3 4-Aug-02 <0.00006 S3 13-Aug-98 <0.00006 S3 4-Aug-02 <0.00006 S3 13-Aug-98 <0.00006 S3 4-Aug-02 <0.00006 S3 13-Aug-98 <0.00006 S3 4-Aug-02 <0.00006 S3 13-Aug-98 <0.00006 S3 3-Sep-02 <0.00006 S3 13-Aug-98 <0.00006 S3 3-Sep-02 <0.00006 S3 03-Sep-98 <0.00006 S3 3-Sep-02 <0.00006 S3 03-Sep-98 <0.00006 S3 3-Sep-02 <0.00006 S3 03-Sep-98 <0.00006 S3 23-Apr-02 <0.00006 S3 03-Sep-98 <0.00006 S3 23-Apr-02 <0.00006 S3 03-Sep-98 <0.00006 S3 23-Apr-02 <0.00006 S3 03-Sep-98 <0.00006 S3 23-Apr-02 <0.00006 S3 12-Jul-99 - S3 3-Jul-03 0.00008 S3 12-Jul-99 - S3 3-Jul-03 0.00009 S3 12-Jul-99 - S3 5-Aug-03 <0.00006 S3 12-Jul-99 - S3 5-Aug-03 <0.00006 S3 12-Jul-99 - S3 3-Sep-03 <0.00006 S3 12-Jul-99 - S3 3-Sep-03 <0.00006 S3 11-Aug-99 - S3 15-Apr-03 <0.00006 S3 11-Aug-99 - S3 15-Apr-03 <0.00006 S3 11-Aug-99 - S3 15-Apr-03 <0.00006 S3 11-Aug-99 - S3 15-Apr-03 <0.00006 S3 11-Aug-99 - S3 17-Apr-04 <0.000050 S3 11-Aug-99 - S3 17-Apr-04 <0.000050 S3 08-Sep-99 - S3 17-Apr-04 0.000051 S3 08-Sep-99 - S3 17-Apr-04 0.000054 S3 08-Sep-99 - S3 12-Jul-04 0.00105 S3 08-Sep-99 - S3 12-Jul-04 0.000986 S3 08-Sep-99 - S3 9-Aug-04 0.000418 S3 08-Sep-99 - S3 9-Aug-04 0.000465 Page 19 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum S3 02-Jul-00 <0.00006 S3 13-Sep-04 0.000164 S3 02-Jul-00 <0.00006 S3 13-Sep-04 0.000162 S3 02-Jul-00 <0.00006 S3 14-Jul-05 0.00138 S3 02-Jul-00 <0.00006 S3 14-Jul-05 0.000654 S3 03-Aug-00 <0.00006 S3 5-Aug-05 0.000427 S3 03-Aug-00 <0.00006 S3 5-Aug-05 0.000443 S3 03-Aug-00 <0.00006 S3 5-Aug-05 0.000437 S3 03-Aug-00 <0.00006 S3 31-Aug-05 0.00021 S3 02-Sep-00 <0.00006 S3 31-Aug-05 0.00019 S3 02-Sep-00 <0.00006 S3 26-Apr-05 0.000266 S3 02-Sep-00 <0.00006 S3 26-Apr-05 0.000235 S3 02-Sep-00 <0.00006 S3 26-Apr-05 0.000131 S3 04-Jul-01 <0.00006 S3 26-Apr-05 0.00015 S3 04-Jul-01 <0.00006 S3 18-Apr-06 0.000096 S3 04-Jul-01 <0.00006 S3 18-Apr-06 0.000512 S3 04-Jul-01 <0.00006 S3 18-Apr-06 0.000081 S3 29-Jul-01 <0.00006 S3 18-Apr-06 0.000066 S3 01-Jul-06 0.000424 S3 15-Apr-10 0.000156 S3 01-Jul-06 0.000439 S3 15-Apr-10 0.000151 S3 01-Jul-06 0.000503 S3 4-Aug-11 0.000412 S3 04-Aug-06 0.0005 S3 4-Aug-11 0.000422 S3 04-Aug-06 0.00029 S3 4-Aug-11 0.000421 S3 05-Sep-06 0.000327 S3 4-Aug-11 0.000465 S3 05-Sep-06 0.000274 S3 4-Aug-11 0.000456 S3 13-Jul-07 0.00131 S3 4-Aug-11 0.000467 S3 13-Jul-07 0.000875 S3 27-Apr-11 0.000318 S3 06-Aug-07 0.000361 S3 27-Apr-11 0.000319 S3 06-Aug-07 0.000328 S3 27-Apr-11 0.00112 S3 06-Aug-07 0.000368 S3 27-Apr-11 0.00115 S3 06-Aug-07 0.000366 Slipper 7-Jul-94 <0.001 S3 06-Aug-07 0.00034 Slipper 7-Jul-94 <0.001 S3 06-Aug-07 0.000411 Slipper 7-Jul-94 <0.001 S3 23-Apr-07 0.000146 Slipper 7-Jul-94 <0.001 S3 23-Apr-07 0.000157 Slipper 7-Jul-94 <0.001 S3 23-Apr-07 0.00132 Slipper 7-Jul-94 <0.001 S3 23-Apr-07 0.00138 Slipper 7-Jul-94 <0.001 S3 13-Sep-07 0.000202 Slipper 7-Jul-94 <0.001 S3 13-Sep-07 0.000247 Slipper 7-Jul-94 <0.001 S3 04-May-08 0.000106 Slipper 7-Jul-94 <0.001 S3 04-May-08 0.000105 Slipper 7-Jul-94 <0.001 S3 04-May-08 0.000113 Slipper 7-Jul-94 <0.001 S3 04-May-08 0.000111 Slipper 7-Jul-94 <0.001 S3 15-Jul-08 0.000664 Slipper 7-Jul-94 <0.001 S3 15-Jul-08 0.000728 Slipper 7-Jul-94 <0.001 S3 15-Jul-08 0.00068 Slipper 15-Aug-94 <0.001 S3 07-Aug-08 0.000416 Slipper 15-Aug-94 <0.001 S3 07-Aug-08 0.000462 Slipper 15-Aug-94 <0.001 S3 07-Aug-08 0.000509 Slipper 15-Aug-94 <0.001 S3 07-Aug-08 0.000233 Slipper 15-Aug-94 <0.001 S3 07-Aug-08 0.000325 Slipper 11-Aug-95 <0.001 S3 07-Aug-08 0.000329 Slipper 11-Aug-95 <0.001 S3 05-Sep-08 0.000438 Slipper 11-Aug-95 <0.001 S3 05-Sep-08 0.000458 Slipper 11-Aug-95 <0.001 S3 17-May-09 0.000264 Slipper 11-Aug-95 <0.001 Page 20 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum S3 17-May-09 0.000361 Slipper 11-Aug-95 <0.001 S3 17-May-09 0.00189 Slipper 17-Apr-96 0.0001 S3 17-May-09 0.00151 Slipper 26-Jul-96 0.0005 S3 13-Jul-09 0.00124 Slipper 26-Jul-96 0.0007 S3 13-Jul-09 0.00119 Slipper 26-Jul-96 0.0006 S3 31-Jul-09 0.00096 Slipper 11-Aug-97 <0.00005 S3 31-Jul-09 0.000759 Slipper 11-Aug-97 0.00005 S3 31-Jul-09 0.000715 Slipper 11-Aug-97 <0.00005 S3 31-Jul-09 0.000695 Slipper 4-Jul-98 0.00009 S3 31-Jul-09 0.000698 Slipper 4-Jul-98 0.00008 S3 31-Jul-09 0.00066 Slipper 4-Jul-98 0.00009 S3 06-Sep-09 0.00037 Slipper 4-Jul-98 0.00009 S3 06-Sep-09 0.000339 Slipper 4-Jul-98 0.00009 S3 06-Aug-10 0.000303 Slipper 4-Jul-98 0.00009 S3 06-Aug-10 0.000288 Slipper 17-Jul-98 0.00016 S3 06-Aug-10 0.000275 Slipper 17-Jul-98 0.0001 S3 05-Aug-10 0.000318 Slipper 17-Jul-98 0.0001 S3 05-Aug-10 0.000292 Slipper 17-Jul-98 0.0001 S3 05-Aug-10 0.000293 Slipper 17-Jul-98 0.00009 S3 15-Apr-10 0.000352 Slipper 17-Jul-98 0.00009 S3 15-Apr-10 0.000334 Slipper 31-Jul-98 0.00007 Slipper 31-Jul-98 0.00007 Slipper 31-Aug-01 0.00026 Slipper 31-Jul-98 0.00007 Slipper 8-Jul-02 0.00028 Slipper 31-Jul-98 0.00006 Slipper 8-Jul-02 0.00029 Slipper 31-Jul-98 0.00007 Slipper 8-Jul-02 0.00022 Slipper 31-Jul-98 0.00007 Slipper 8-Jul-02 0.00023 Slipper 12-Aug-98 0.00008 Slipper 6-Aug-02 0.00033 Slipper 12-Aug-98 0.00008 Slipper 6-Aug-02 0.00033 Slipper 12-Aug-98 0.00008 Slipper 6-Aug-02 0.00032 Slipper 12-Aug-98 0.00008 Slipper 6-Aug-02 0.00033 Slipper 12-Aug-98 0.00007 Slipper 3-Sep-02 0.00042 Slipper 12-Aug-98 0.00007 Slipper 3-Sep-02 0.00044 Slipper 03-Sep-98 0.00008 Slipper 3-Sep-02 0.00042 Slipper 03-Sep-98 0.00008 Slipper 3-Sep-02 0.00042 Slipper 03-Sep-98 0.00008 Slipper 23-Apr-02 0.00034 Slipper 03-Sep-98 0.00007 Slipper 23-Apr-02 0.00033 Slipper 03-Sep-98 0.00007 Slipper 23-Apr-02 0.00038 Slipper 03-Sep-98 0.00007 Slipper 23-Apr-02 0.00033 Slipper 10-Jul-99 - Slipper 2-Jul-03 0.00037 Slipper 10-Jul-99 - Slipper 2-Jul-03 0.00036 Slipper 10-Jul-99 - Slipper 7-Aug-03 0.00052 Slipper 10-Jul-99 - Slipper 7-Aug-03 0.00053 Slipper 10-Jul-99 - Slipper 7-Aug-03 0.0005 Slipper 10-Jul-99 - Slipper 3-Sep-03 0.00051 Slipper 09-Aug-99 - Slipper 3-Sep-03 0.00051 Slipper 09-Aug-99 - Slipper 15-Apr-03 0.00074 Slipper 09-Aug-99 - Slipper 15-Apr-03 0.0009 Slipper 09-Aug-99 - Slipper 15-Apr-03 0.00054 Slipper 09-Aug-99 - Slipper 15-Apr-03 0.00056 Slipper 09-Aug-99 - Slipper 17-Apr-04 0.000786 Slipper 07-Sep-99 - Slipper 17-Apr-04 0.000807 Slipper 07-Sep-99 - Slipper 17-Apr-04 0.000588 Slipper 07-Sep-99 - Slipper 17-Apr-04 0.000594 Slipper 07-Sep-99 - Slipper 9-Jul-04 0.00203 Page 21 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Slipper 07-Sep-99 - Slipper 9-Jul-04 0.00222 Slipper 07-Sep-99 - Slipper 12-Aug-04 0.00188 Slipper 29-Jun-00 0.00009 Slipper 12-Aug-04 0.00192 Slipper 29-Jun-00 0.0001 Slipper 12-Aug-04 0.00183 Slipper 29-Jun-00 0.00018 Slipper 12-Sep-04 0.00165 Slipper 29-Jun-00 0.00009 Slipper 12-Sep-04 0.0016 Slipper 31-Jul-00 0.00011 Slipper 10-Jul-05 0.00495 Slipper 31-Jul-00 0.00012 Slipper 10-Jul-05 0.0045 Slipper 31-Jul-00 0.0001 Slipper 5-Aug-05 0.0056 Slipper 31-Jul-00 0.00011 Slipper 5-Aug-05 0.00545 Slipper 02-Sep-00 0.00012 Slipper 1-Sep-05 0.00528 Slipper 02-Sep-00 0.00013 Slipper 1-Sep-05 0.00519 Slipper 02-Sep-00 0.00012 Slipper 1-Sep-05 0.00525 Slipper 02-Sep-00 0.00013 Slipper 26-Apr-05 0.00297 Slipper 04-Jul-01 0.00022 Slipper 26-Apr-05 0.00309 Slipper 04-Jul-01 0.00021 Slipper 26-Apr-05 0.00375 Slipper 04-Jul-01 0.00019 Slipper 26-Apr-05 0.00389 Slipper 04-Jul-01 0.00018 Slipper 18-Apr-06 0.00404 Slipper 29-Jul-01 0.00022 Slipper 18-Apr-06 0.00371 Slipper 29-Jul-01 0.00025 Slipper 18-Apr-06 0.00416 Slipper 29-Jul-01 0.00018 Slipper 18-Apr-06 0.00418 Slipper 29-Jul-01 0.0002 Slipper 1-Jul-06 0.00297 Slipper 31-Aug-01 0.00027 Slipper 1-Jul-06 0.00286 Slipper 31-Aug-01 0.00025 Slipper 4-Aug-06 0.00487 Slipper 31-Aug-01 0.00027 Slipper 4-Aug-06 0.00457 Slipper 06-Sep-06 0.0055 Slipper 3-Aug-11 0.00449 Slipper 06-Sep-06 0.00532 Slipper 3-Aug-11 0.0045 Slipper 13-Jul-07 0.00362 Slipper 3-Aug-11 0.00456 Slipper 13-Jul-07 0.00365 Slipper 3-Aug-11 0.00454 Slipper 13-Jul-07 0.00347 Slipper 3-Aug-11 0.00453 Slipper 10-Aug-07 0.00443 Slipper 27-Apr-11 0.00543 Slipper 10-Aug-07 0.00467 Slipper 27-Apr-11 0.00546 Slipper 10-Aug-07 0.00458 Slipper 27-Apr-11 0.00434 Slipper 10-Aug-07 0.00437 Slipper 27-Apr-11 0.0044 Slipper 10-Aug-07 0.00482 Vulture 1-Jul-94 <0.001 Slipper 10-Aug-07 0.0044 Vulture 1-Jul-94 <0.001 Slipper 24-Apr-07 0.00799 Vulture 1-Jul-94 <0.001 Slipper 24-Apr-07 0.00802 Vulture 1-Jul-94 <0.001 Slipper 24-Apr-07 0.00703 Vulture 1-Jul-94 <0.001 Slipper 24-Apr-07 0.00708 Vulture 13-Aug-94 <0.001 Slipper 13-Sep-07 0.00481 Vulture 13-Aug-94 <0.001 Slipper 13-Sep-07 0.00464 Vulture 13-Aug-94 <0.001 Slipper 04-May-08 0.00525 Vulture 13-Aug-94 <0.001 Slipper 04-May-08 0.0056 Vulture 13-Aug-94 <0.001 Slipper 04-May-08 0.00467 Vulture 9-Aug-95 <0.001 Slipper 04-May-08 0.00455 Vulture 9-Aug-95 <0.001 Slipper 08-Jul-08 0.00471 Vulture 9-Aug-95 <0.001 Slipper 08-Jul-08 0.00545 Vulture 9-Aug-95 <0.001 Slipper 08-Jul-08 0.00461 Vulture 9-Aug-95 <0.001 Slipper 29-Jul-08 0.00541 Vulture 18-Apr-96 0.0001 Slipper 29-Jul-08 0.00538 Vulture 26-Jul-96 <0.00005 Slipper 29-Jul-08 0.00537 Vulture 26-Jul-96 <0.00005 Slipper 29-Jul-08 0.00525 Vulture 26-Jul-96 <0.00005 Slipper 29-Jul-08 0.0051 Vulture 5-Aug-97 <0.00005 Page 22 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Slipper 29-Jul-08 0.00524 Vulture 5-Aug-97 <0.00005 Slipper 06-Sep-08 0.00489 Vulture 5-Aug-97 <0.00005 Slipper 06-Sep-08 0.00544 Vulture 5-Aug-97 <0.00005 Slipper 17-May-09 0.00762 Vulture 5-Aug-97 <0.00005 Slipper 17-May-09 0.00771 Vulture 5-Aug-97 <0.00005 Slipper 17-May-09 0.00657 Vulture 5-Aug-97 <0.00005 Slipper 17-May-09 0.00723 Vulture 5-Aug-97 <0.00005 Slipper 03-Jul-09 0.00392 Vulture 5-Aug-97 <0.00005 Slipper 03-Jul-09 0.00415 Vulture 29-Jun-98 <0.00006 Slipper 03-Jul-09 0.004 Vulture 29-Jun-98 <0.00006 Slipper 03-Aug-09 0.00492 Vulture 29-Jun-98 <0.00006 Slipper 03-Aug-09 0.00469 Vulture 29-Jun-98 <0.00006 Slipper 03-Aug-09 0.00469 Vulture 29-Jun-98 <0.00006 Slipper 03-Aug-09 0.00456 Vulture 29-Jun-98 <0.00006 Slipper 03-Aug-09 0.00475 Vulture 14-Jul-98 <0.00006 Slipper 03-Aug-09 0.00472 Vulture 14-Jul-98 <0.00006 Slipper 07-Sep-09 0.00517 Vulture 14-Jul-98 <0.00006 Slipper 07-Sep-09 0.00481 Vulture 14-Jul-98 <0.00006 Slipper 05-Aug-10 0.00474 Vulture 14-Jul-98 <0.00006 Slipper 05-Aug-10 0.00465 Vulture 14-Jul-98 0.00008 Slipper 05-Aug-10 0.00468 Vulture 27-Jul-98 <0.00006 Slipper 05-Aug-10 0.00464 Vulture 27-Jul-98 0.00007 Slipper 05-Aug-10 0.00462 Vulture 27-Jul-98 <0.00006 Slipper 05-Aug-10 0.00453 Vulture 27-Jul-98 <0.00006 Slipper 15-Apr-10 0.00343 Vulture 27-Jul-98 <0.00006 Slipper 15-Apr-10 0.0036 Vulture 27-Jul-98 <0.00006 Slipper 15-Apr-10 0.00451 Vulture 10-Aug-98 <0.00006 Slipper 15-Apr-10 0.00458 Vulture 10-Aug-98 <0.00006 Slipper 03-Aug-11 0.00446 Vulture 10-Aug-98 <0.00006 Vulture 10-Aug-98 <0.00006 Vulture 3-Aug-02 <0.00006 Vulture 10-Aug-98 <0.00006 Vulture 9-Sep-02 <0.00006 Vulture 10-Aug-98 <0.00006 Vulture 9-Sep-02 <0.00006 Vulture 02-Sep-98 <0.00006 Vulture 9-Sep-02 <0.00006 Vulture 02-Sep-98 <0.00006 Vulture 9-Sep-02 <0.00006 Vulture 02-Sep-98 <0.00006 Vulture 20-Apr-02 <0.00006 Vulture 02-Sep-98 <0.00006 Vulture 20-Apr-02 <0.00006 Vulture 02-Sep-98 <0.00006 Vulture 20-Apr-02 <0.00006 Vulture 02-Sep-98 <0.00006 Vulture 20-Apr-02 <0.00006 Vulture 08-Jul-99 - Vulture 5-Jul-03 <0.00006 Vulture 08-Jul-99 - Vulture 5-Jul-03 <0.00006 Vulture 08-Jul-99 - Vulture 5-Jul-03 <0.00006 Vulture 08-Jul-99 - Vulture 4-Aug-03 <0.00006 Vulture 08-Jul-99 - Vulture 4-Aug-03 <0.00006 Vulture 08-Jul-99 - Vulture 7-Sep-03 <0.00006 Vulture 06-Aug-99 - Vulture 7-Sep-03 <0.00006 Vulture 06-Aug-99 - Vulture 14-Apr-03 <0.00006 Vulture 06-Aug-99 - Vulture 14-Apr-03 <0.00006 Vulture 06-Aug-99 - Vulture 14-Apr-03 <0.00006 Vulture 06-Aug-99 - Vulture 14-Apr-03 <0.00006 Vulture 06-Aug-99 - Vulture 11-Jul-04 <0.000050 Vulture 03-Sep-99 - Vulture 11-Jul-04 <0.000050 Vulture 03-Sep-99 - Vulture 11-Jul-04 <0.000050 Vulture 03-Sep-99 - Vulture 9-Aug-04 <0.000050 Vulture 03-Sep-99 - Vulture 9-Aug-04 <0.000050 Page 23 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Vulture 03-Sep-99 - Vulture 7-Sep-04 <0.000050 Vulture 03-Sep-99 - Vulture 7-Sep-04 <0.000050 Vulture 03-Jul-00 <0.00006 Vulture 18-Apr-04 <0.000050 Vulture 03-Jul-00 <0.00006 Vulture 18-Apr-04 <0.000050 Vulture 03-Jul-00 <0.00006 Vulture 18-Apr-04 <0.000050 Vulture 03-Jul-00 <0.00006 Vulture 18-Apr-04 <0.000050 Vulture 04-Aug-00 <0.00006 Vulture 10-Jul-05 0.000144 Vulture 04-Aug-00 <0.00006 Vulture 10-Jul-05 <0.00005 Vulture 04-Aug-00 <0.00006 Vulture 31-Jul-05 <0.00005 Vulture 04-Aug-00 <0.00006 Vulture 31-Jul-05 <0.00005 Vulture 05-Sep-00 <0.00006 Vulture 1-Sep-05 <0.00005 Vulture 05-Sep-00 <0.00006 Vulture 1-Sep-05 <0.00005 Vulture 05-Sep-00 <0.00006 Vulture 24-Apr-05 <0.000050 Vulture 05-Sep-00 <0.00006 Vulture 24-Apr-05 <0.000050 Vulture 07-Jul-01 <0.00006 Vulture 24-Apr-05 <0.000050 Vulture 07-Jul-01 <0.00006 Vulture 24-Apr-05 <0.000050 Vulture 07-Jul-01 <0.00006 Vulture 21-Apr-06 <0.000050 Vulture 07-Jul-01 <0.00006 Vulture 21-Apr-06 <0.000050 Vulture 02-Aug-01 <0.00006 Vulture 21-Apr-06 <0.000050 Vulture 02-Aug-01 <0.00006 Vulture 21-Apr-06 <0.000050 Vulture 02-Aug-01 <0.00006 Vulture 30-Jun-06 <0.000050 Vulture 02-Aug-01 <0.00006 Vulture 30-Jun-06 <0.000050 Vulture 01-Sep-01 <0.00006 Vulture 30-Jun-06 <0.000050 Vulture 01-Sep-01 <0.00006 Vulture 2-Aug-06 <0.000050 Vulture 01-Sep-01 <0.00006 Vulture 2-Aug-06 <0.000050 Vulture 01-Sep-01 <0.00006 Vulture 5-Sep-06 <0.000050 Vulture 04-Jul-02 <0.00006 Vulture 5-Sep-06 <0.000050 Vulture 04-Jul-02 <0.00006 Vulture 10-Jul-07 <0.00025 Vulture 04-Jul-02 <0.00006 Vulture 10-Jul-07 <0.000050 Vulture 04-Jul-02 <0.00006 Vulture 12-Aug-07 <0.000050 Vulture 03-Aug-02 <0.00006 Vulture 12-Aug-07 <0.000050 Vulture 03-Aug-02 <0.00006 Vulture 12-Aug-07 <0.000050 Vulture 03-Aug-02 <0.00006 Vulture 12-Aug-07 <0.000050 Vulture 12-Aug-07 <0.000050 Vulture 12-Aug-07 <0.000050 Vulture 22-Apr-07 <0.000050 Vulture 22-Apr-07 <0.000050 Vulture 22-Apr-07 <0.000050 Vulture 22-Apr-07 <0.000050 Vulture 10-Sep-07 <0.000050 Vulture 10-Sep-07 <0.000050 Vulture 03-May-08 <0.000050 Vulture 03-May-08 <0.000050 Vulture 03-May-08 <0.000050 Vulture 03-May-08 <0.000050 Vulture 13-Jul-08 <0.000050 Vulture 13-Jul-08 0.000146 Vulture 29-Jul-08 0.000232 Vulture 29-Jul-08 <0.000050 Vulture 29-Jul-08 <0.000050 Vulture 29-Jul-08 0.000072 Vulture 29-Jul-08 <0.000050 Vulture 29-Jul-08 <0.000050 Vulture 09-Sep-08 <0.000050 Page 24 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Lake Date Molybdenum Lake Date Molybdenum Vulture 09-Sep-08 <0.000050 Vulture 28-Apr-09 <0.000050 Vulture 28-Apr-09 <0.000050 Vulture 28-Apr-09 <0.000050 Vulture 28-Apr-09 <0.000050 Vulture 15-Jul-09 0.00013 Vulture 15-Jul-09 <0.000050 Vulture 15-Jul-09 <0.000050 Vulture 30-Jul-09 0.000116 Vulture 30-Jul-09 <0.000050 Vulture 30-Jul-09 <0.000050 Vulture 30-Jul-09 <0.000050 Vulture 30-Jul-09 <0.000050 Vulture 30-Jul-09 <0.000050 Vulture 06-Sep-09 <0.000050 Vulture 06-Sep-09 <0.000050 Vulture 05-Aug-10 0.000079 Vulture 05-Aug-10 <0.000050 Vulture 05-Aug-10 <0.000050 Vulture 05-Aug-10 <0.000050 Vulture 05-Aug-10 <0.000050 Vulture 05-Aug-10 0.000059 Vulture 12-Apr-10 <0.000050 Vulture 12-Apr-10 <0.000050 Vulture 12-Apr-10 <0.000050 Vulture 12-Apr-10 <0.000050 Vulture 05-Aug-11 <0.000050 Vulture 05-Aug-11 <0.000050 Vulture 05-Aug-11 <0.000050 Vulture 05-Aug-11 <0.000050 Vulture 05-Aug-11 <0.000050 Vulture 05-Aug-11 <0.000050 Vulture 28-Apr-11 <0.000050 Vulture 28-Apr-11 <0.000050 Vulture 28-Apr-11 <0.000050 Vulture 28-Apr-11 <0.000050 Dashes indicate that no analyses or information is available. < indicates less than the detection limit

Page 25 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum 1616-30 (LLCF) 1-May-98 - 1616-30 (LLCF) 26-Jul-04 0.0356 1616-30 (LLCF) 20-Jul-98 - 1616-30 (LLCF) 2-Aug-04 0.0374 1616-30 (LLCF) 18-Aug-98 - 1616-30 (LLCF) 2-Aug-04 0.0384 1616-30 (LLCF) 19-Sep-98 0.0001 1616-30 (LLCF) 11-Aug-04 0.0378 1616-30 (LLCF) 7-Jun-99 - 1616-30 (LLCF) 11-Aug-04 0.0392 1616-30 (LLCF) 9-Aug-99 - 1616-30 (LLCF) 11-Aug-04 0.0399 1616-30 (LLCF) 13-Sep-99 - 1616-30 (LLCF) 11-Aug-04 0.0391 1616-30 (LLCF) 12-Jun-00 0.0015 1616-30 (LLCF) 23-Aug-04 0.0313 1616-30 (LLCF) 31-Jul-00 0.004 1616-30 (LLCF) 30-Aug-04 0.0412 1616-30 (LLCF) 4-Sep-00 0.0046 1616-30 (LLCF) 9-Sep-04 0.043 1616-30 (LLCF) 14-Jun-01 0.00307 1616-30 (LLCF) 9-Sep-04 0.0419 1616-30 (LLCF) 14-Jun-01 0.00319 1616-30 (LLCF) 6-Jun-05 0.0471 1616-30 (LLCF) 14-Jun-01 0.00321 1616-30 (LLCF) 13-Jun-05 0.0529 1616-30 (LLCF) 7-Aug-01 0.00889 1616-30 (LLCF) 13-Jun-05 0.0454 1616-30 (LLCF) 7-Aug-01 0.00901 1616-30 (LLCF) 13-Jun-05 0.0477 1616-30 (LLCF) 7-Aug-01 0.00892 1616-30 (LLCF) 20-Jun-05 0.0565 1616-30 (LLCF) 8-Sep-01 0.0104 1616-30 (LLCF) 27-Jun-05 0.065 1616-30 (LLCF) 8-Sep-01 0.0104 1616-30 (LLCF) 13-Jul-05 0.0665 1616-30 (LLCF) 8-Sep-01 0.0103 1616-30 (LLCF) 2-Aug-05 0.0699 1616-30 (LLCF) 15-Jul-02 0.0126 1616-30 (LLCF) 2-Aug-05 0.0667 1616-30 (LLCF) 15-Jul-02 0.0128 1616-30 (LLCF) 29-Aug-05 0.0649 1616-30 (LLCF) 15-Jul-02 0.0126 1616-30 (LLCF) 5-Sep-05 0.066 1616-30 (LLCF) 6-Aug-02 0.0141 1616-30 (LLCF) 5-Sep-05 0.0667 1616-30 (LLCF) 6-Aug-02 0.0142 1616-30 (LLCF) 5-Sep-05 0.0642 1616-30 (LLCF) 6-Aug-02 0.0143 1616-30 (LLCF) 12-Sep-05 0.0592 1616-30 (LLCF) 11-Sep-02 0.0157 1616-30 (LLCF) 19-Sep-05 0.0697 1616-30 (LLCF) 11-Sep-02 0.0158 1616-30 (LLCF) 26-Sep-05 0.0633 1616-30 (LLCF) 11-Sep-02 0.0156 1616-30 (LLCF) 21-May-06 0.021 1616-30 (LLCF) 12-Jun-03 0.0109 1616-30 (LLCF) 21-May-06 0.0209 1616-30 (LLCF) 12-Jun-03 0.0108 1616-30 (LLCF) 23-Jun-06 0.0583 1616-30 (LLCF) 2-Aug-03 0.0181 1616-30 (LLCF) 27-Jun-06 0.0609 1616-30 (LLCF) 2-Aug-03 0.0185 1616-30 (LLCF) 27-Jun-06 0.0606 1616-30 (LLCF) 4-Sep-03 0.0213 1616-30 (LLCF) 5-Jul-06 0.061 1616-30 (LLCF) 4-Sep-03 0.021 1616-30 (LLCF) 5-Jul-06 0.0597 1616-30 (LLCF) 12-Jun-04 0.00431 1616-30 (LLCF) 8-Jul-06 0.0597 1616-30 (LLCF) 12-Jun-04 0.00418 1616-30 (LLCF) 8-Jul-06 0.0599 1616-30 (LLCF) 20-Jun-04 0.00502 1616-30 (LLCF) 10-Jul-06 0.0603 1616-30 (LLCF) 20-Jun-04 0.00479 1616-30 (LLCF) 20-Jul-06 0.0652 1616-30 (LLCF) 20-Jun-04 - 1616-30 (LLCF) 20-Jul-06 0.064 1616-30 (LLCF) 24-Jun-04 0.00269 1616-30 (LLCF) 26-Jul-06 0.0654 1616-30 (LLCF) 2-Jul-04 0.0204 1616-30 (LLCF) 26-Jul-06 0.0643 1616-30 (LLCF) 5-Jul-04 0.0248 1616-30 (LLCF) 31-Jul-06 0.0695 1616-30 (LLCF) 12-Jul-04 0.0353 1616-30 (LLCF) 4-Aug-06 0.0667 1616-30 (LLCF) 19-Jul-04 0.0369 1616-30 (LLCF) 23-Aug-06 0.0679 1616-30 (LLCF) 26-Jul-04 0.0359 1616-30 (LLCF) 27-Jul-06 0.0644 1616-30 (LLCF) 29-Jul-06 0.0656 1616-30 (LLCF) 22-Sep-08 0.0602 1616-30 (LLCF) 2-Sep-06 0.0696 1616-30 (LLCF) 29-Sep-08 0.0631 1616-30 (LLCF) 9-Sep-06 0.0735 1616-30 (LLCF) 11-Jun-09 0.0073 1616-30 (LLCF) 5-Sep-06 0.0666 1616-30 (LLCF) 11-Jun-09 0.00731 1616-30 (LLCF) 6-Sep-07 0.079 1616-30 (LLCF) 21-Jun-09 0.0146 1616-30 (LLCF) 6-Sep-07 0.0795 1616-30 (LLCF) 21-Jun-09 0.0139 1616-30 (LLCF) 6-Jun-07 0.00541 1616-30 (LLCF) 29-Jun-09 0.0943 1616-30 (LLCF) 12-Aug-07 0.0726 1616-30 (LLCF) 29-Jun-09 0.093 1616-30 (LLCF) 12-Aug-07 0.0724 1616-30 (LLCF) 6-Jul-09 0.0594

Page 26 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum 1616-30 (LLCF) 16-Jun-07 0.0101 1616-30 (LLCF) 6-Jul-09 0.0592 1616-30 (LLCF) 16-Jun-07 0.0101 1616-30 (LLCF) 19-Jul-09 0.0664 1616-30 (LLCF) 23-Jun-07 0.0126 1616-30 (LLCF) 19-Jul-09 0.0648 1616-30 (LLCF) 30-Jun-07 0.0127 1616-30 (LLCF) 3-Aug-09 0.0655 1616-30 (LLCF) 30-Jun-07 0.0732 1616-30 (LLCF) 3-Aug-09 0.0677 1616-30 (LLCF) 6-Jun-07 0.0739 1616-30 (LLCF) 6-Aug-09 0.0668 1616-30 (LLCF) 7-Jul-07 0.0653 1616-30 (LLCF) 6-Aug-09 0.0668 1616-30 (LLCF) 7-Jul-07 0.0649 1616-30 (LLCF) 10-Aug-09 0.0662 1616-30 (LLCF) 14-Jul-07 0.0645 1616-30 (LLCF) 10-Aug-09 0.0667 1616-30 (LLCF) 14-Jul-07 0.0643 1616-30 (LLCF) 17-Aug-09 0.0685 1616-30 (LLCF) 24-Jul-07 0.0638 1616-30 (LLCF) 17-Aug-09 0.0671 1616-30 (LLCF) 24-Jul-07 0.0652 1616-30 (LLCF) 24-Aug-09 0.0727 1616-30 (LLCF) 28-Jul-07 0.0683 1616-30 (LLCF) 24-Aug-09 0.0725 1616-30 (LLCF) 28-Jul-07 0.0689 1616-30 (LLCF) 31-Aug-09 0.0727 1616-30 (LLCF) 30-Aug-07 0.0762 1616-30 (LLCF) 31-Aug-09 0.0696 1616-30 (LLCF) 30-Aug-07 0.0772 1616-30 (LLCF) 5-Sep-09 0.0672 1616-30 (LLCF) 1-Sep-07 0.0769 1616-30 (LLCF) 5-Sep-09 0.0691 1616-30 (LLCF) 1-Sep-07 0.0745 1616-30 (LLCF) 7-Sep-09 0.0716 1616-30 (LLCF) 3-Sep-07 - 1616-30 (LLCF) 7-Sep-09 0.0698 1616-30 (LLCF) 3-Sep-07 - 1616-30 (LLCF) 14-Sep-09 0.0785 1616-30 (LLCF) 8-Sep-07 0.0772 1616-30 (LLCF) 14-Sep-09 0.0742 1616-30 (LLCF) 8-Sep-07 0.074 1616-30 (LLCF) 21-Sep-09 0.0779 1616-30 (LLCF) 14-Jul-08 - 1616-30 (LLCF) 21-Sep-09 0.0792 1616-30 (LLCF) 14-Jul-08 - 1616-30 (LLCF) 28-Sep-09 0.0728 1616-30 (LLCF) 4-Aug-08 0.0587 1616-30 (LLCF) 28-Sep-09 0.0721 1616-30 (LLCF) 4-Aug-08 0.0591 1616-30 (LLCF) 8-Jun-10 0.00467 1616-30 (LLCF) 24-Aug-08 0.0631 1616-30 (LLCF) 8-Jun-10 0.00492 1616-30 (LLCF) 24-Aug-08 0.0626 1616-30 (LLCF) 21-Jun-10 0.0473 1616-30 (LLCF) 1-Sep-08 0.0601 1616-30 (LLCF) 21-Jun-10 0.0497 1616-30 (LLCF) 1-Sep-08 0.0608 1616-30 (LLCF) 4-Jul-10 0.0626 1616-30 (LLCF) 8-Sep-08 0.0661 1616-30 (LLCF) 4-Jul-10 0.0654 1616-30 (LLCF) 8-Sep-08 0.0675 1616-30 (LLCF) 17-Jul-10 0.0657 1616-30 (LLCF) 8-Sep-08 0.0637 1616-30 (LLCF) 17-Jul-10 0.0644 1616-30 (LLCF) 8-Sep-08 0.0634 1616-30 (LLCF) 19-Jul-10 0.0666 1616-30 (LLCF) 13-Sep-08 0.0606 1616-30 (LLCF) 19-Jul-10 0.0705 1616-30 (LLCF) 13-Sep-08 0.0629 1616-30 (LLCF) 26-Jul-10 0.0664 1616-30 (LLCF) 15-Sep-08 0.0654 1616-30 (LLCF) 26-Jul-10 0.0664 1616-30 (LLCF) 13-Jul-10 - 1616-43 (KPSF) 16-Jun-02 - 1616-30 (LLCF) 13-Jul-10 - 1616-43 (KPSF) 16-Jun-02 - 1616-30 (LLCF) 3-Aug-10 0.0695 1616-43 (KPSF) 6-Aug-02 0.00592 1616-30 (LLCF) 3-Aug-10 0.067 1616-43 (KPSF) 6-Aug-02 0.00585 1616-30 (LLCF) 9-Aug-10 0.0721 1616-43 (KPSF) 6-Aug-02 0.00588 1616-30 (LLCF) 9-Aug-10 0.0702 1616-43 (KPSF) 11-Sep-02 0.00939 1616-30 (LLCF) 16-Aug-10 0.0716 1616-43 (KPSF) 11-Sep-02 0.00912 1616-30 (LLCF) 16-Aug-10 0.0728 1616-43 (KPSF) 11-Sep-02 0.00891 1616-30 (LLCF) 23-Aug-10 0.0726 1616-43 (KPSF) 12-Jun-03 0.00425 1616-30 (LLCF) 23-Aug-10 0.0717 1616-43 (KPSF) 12-Jun-03 0.00418 1616-30 (LLCF) 30-Aug-10 0.0756 1616-43 (KPSF) 2-Aug-03 0.00776 1616-30 (LLCF) 30-Aug-10 0.0783 1616-43 (KPSF) 2-Aug-03 0.00775 1616-30 (LLCF) 7-Sep-10 0.0755 1616-43 (KPSF) 4-Sep-03 0.0107 1616-30 (LLCF) 7-Sep-10 0.076 1616-43 (KPSF) 4-Sep-03 0.0106 1616-30 (LLCF) 13-Sep-10 0.082 1616-43 (KPSF) 20-Jun-04 0.00542 1616-30 (LLCF) 13-Sep-10 0.0812 1616-43 (KPSF) 20-Jun-04 0.00508 1616-30 (LLCF) 21-Sep-10 0.0792 1616-43 (KPSF) 11-Aug-04 0.00813 1616-30 (LLCF) 21-Sep-10 0.0784 1616-43 (KPSF) 11-Aug-04 0.00803

Page 27 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum 1616-30 (LLCF) 27-Sep-10 0.0779 1616-43 (KPSF) 19-Aug-04 0.00883 1616-30 (LLCF) 27-Sep-10 0.0783 1616-43 (KPSF) 19-Aug-04 0.00897 1616-30 (LLCF) 12-Jun-11 0.0252 1616-43 (KPSF) 11-Sep-04 0.00886 1616-30 (LLCF) 12-Jun-11 0.0217 1616-43 (KPSF) 9-Sep-04 0.00821 1616-30 (LLCF) 21-Jun-11 0.077 1616-43 (KPSF) 9-Sep-04 0.00848 1616-30 (LLCF) 21-Jun-11 0.0759 1616-43 (KPSF) 13-Jun-05 0.00225 1616-30 (LLCF) 26-Jun-11 - 1616-43 (KPSF) 13-Jun-05 0.00218 1616-30 (LLCF) 26-Jun-11 - 1616-43 (KPSF) 27-Jun-05 0.00369 1616-30 (LLCF) 6-Jul-11 0.0721 1616-43 (KPSF) 25-Jul-05 0.00658 1616-30 (LLCF) 6-Jul-11 0.0722 1616-43 (KPSF) 2-Aug-05 0.00568 1616-30 (LLCF) 11-Jul-11 0.071 1616-43 (KPSF) 2-Aug-05 0.0057 1616-30 (LLCF) 11-Jul-11 0.0719 1616-43 (KPSF) 5-Sep-05 0.00604 1616-30 (LLCF) 18-Jul-11 0.0758 1616-43 (KPSF) 5-Sep-05 0.00581 1616-30 (LLCF) 25-Jul-11 0.0811 1616-43 (KPSF) 5-Sep-05 0.00566 1616-30 (LLCF) 31-Jul-11 0.0773 1616-43 (KPSF) 21-Sep-05 0.00545 1616-30 (LLCF) 31-Jul-11 0.0835 1616-43 (KPSF) 26-Sep-05 0.00566 1616-30 (LLCF) 2-Aug-11 0.0827 1616-43 (KPSF) 21-May-06 0.00292 1616-30 (LLCF) 8-Aug-11 0.087 1616-43 (KPSF) 21-May-06 0.00299 1616-30 (LLCF) 8-Aug-11 0.085 1616-43 (KPSF) 27-Jun-06 0.0126 1616-30 (LLCF) 14-Aug-11 0.0881 1616-43 (KPSF) 7-Aug-06 0.0144 1616-30 (LLCF) 24-Aug-11 0.0807 1616-43 (KPSF) 21-Aug-06 0.0152 1616-30 (LLCF) 29-Aug-11 0.0887 1616-43 (KPSF) 21-Aug-06 0.0147 1616-30 (LLCF) 5-Sep-11 0.0846 1616-43 (KPSF) 27-Jul-06 0.014 1616-30 (LLCF) 5-Sep-11 0.0848 1616-43 (KPSF) 27-Jul-06 0.0135 1616-30 (LLCF) 12-Sep-11 0.0797 1616-43 (KPSF) 2-Sep-06 0.013 1616-30 (LLCF) 19-Sep-11 0.0851 1616-43 (KPSF) 9-Sep-06 0.0143 1616-30 (LLCF) 26-Sep-11 0.0882 1616-43 (KPSF) 5-Sep-06 0.0136 1616-43 (KPSF) 16-Jun-02 - 1616-43 (KPSF) 5-Sep-06 0.0129 1616-43 (KPSF) 5-Sep-07 0.0382 1616-43 (KPSF) 28-Jun-10 0.00338 1616-43 (KPSF) 5-Sep-07 0.038 1616-43 (KPSF) 7-Jul-10 0.0037 1616-43 (KPSF) 6-Jun-07 0.00201 1616-43 (KPSF) 7-Jul-10 0.00373 1616-43 (KPSF) 3-Aug-07 0.00693 1616-43 (KPSF) 2-Aug-10 0.0044 1616-43 (KPSF) 3-Aug-07 0.00691 1616-43 (KPSF) 2-Aug-10 0.00427 1616-43 (KPSF) 31-May-07 0.00172 1616-43 (KPSF) 16-Aug-10 0.00513 1616-43 (KPSF) 31-May-07 0.0017 1616-43 (KPSF) 29-Aug-10 0.00798 1616-43 (KPSF) 25-Jun-07 0.00377 1616-43 (KPSF) 31-Aug-10 0.0154 1616-43 (KPSF) 9-Jul-07 0.00569 1616-43 (KPSF) 31-Aug-10 0.016 1616-43 (KPSF) 9-Jul-07 0.00564 1616-43 (KPSF) 26-Aug-10 0.00584 1616-43 (KPSF) 14-Jul-07 0.00635 1616-43 (KPSF) 9-Sep-10 0.0218 1616-43 (KPSF) 14-Jul-07 0.0066 1616-43 (KPSF) 9-Sep-10 0.0217 1616-43 (KPSF) 10-Jun-08 0.00551 1616-43 (KPSF) 13-Sep-10 0.0221 1616-43 (KPSF) 29-Jun-08 0.00589 1616-43 (KPSF) 20-Sep-10 0.0242 1616-43 (KPSF) 7-Jul-08 0.00681 1616-43 (KPSF) 12-Jun-11 0.00456 1616-43 (KPSF) 15-Jul-08 0.00789 1616-43 (KPSF) 12-Jun-11 0.00454 1616-43 (KPSF) 21-Jul-08 0.00894 1616-43 (KPSF) 2-Jul-11 0.0059 1616-43 (KPSF) 27-Jul-08 0.00972 1616-43 (KPSF) 2-Jul-11 0.00597 1616-43 (KPSF) 1-Aug-08 0.0105 1616-43 (KPSF) 30-Jul-11 0.000056 1616-43 (KPSF) 1-Aug-08 0.0104 1616-43 (KPSF) 30-Jul-11 <0.000050 1616-43 (KPSF) 2-Sep-08 0.00836 1616-43 (KPSF) 16-Aug-11 0.00266 1616-43 (KPSF) 2-Sep-08 0.00858 1616-43 (KPSF) 16-Aug-11 0.00316 1616-43 (KPSF) 6-Sep-08 0.00795 1616-43 (KPSF) 30-Aug-11 0.0204 1616-43 (KPSF) 22-Sep-08 0.00715 1616-43 (KPSF) 30-Aug-11 0.0207 1616-43 (KPSF) 29-Sep-08 0.00661 1616-43 (KPSF) 10-Sep-11 0.0216 1616-43 (KPSF) 11-Jun-09 0.00165 1616-43 (KPSF) 11-Sep-11 0.0225

Page 28 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum 1616-43 (KPSF) 13-Jun-09 0.00205 Christine-Lac du Sauvage 28-Jun-00 <0.00006 1616-43 (KPSF) 13-Jun-09 0.00216 Christine-Lac du Sauvage 28-Jun-00 <0.00006 1616-43 (KPSF) 29-Jun-09 0.00365 Christine-Lac du Sauvage 28-Jun-00 <0.00006 1616-43 (KPSF) 9-Jul-09 0.0053 Christine-Lac du Sauvage 3-Aug-00 <0.00006 1616-43 (KPSF) 3-Aug-09 0.00532 Christine-Lac du Sauvage 3-Aug-00 <0.00006 1616-43 (KPSF) 3-Aug-09 0.00516 Christine-Lac du Sauvage 3-Aug-00 <0.00006 1616-43 (KPSF) 4-Aug-09 0.00538 Christine-Lac du Sauvage 7-Sep-00 <0.00006 1616-43 (KPSF) 2-Sep-09 0.00643 Christine-Lac du Sauvage 7-Sep-00 <0.00006 1616-43 (KPSF) 4-Sep-09 0.00639 Christine-Lac du Sauvage 7-Sep-00 <0.00006 1616-43 (KPSF) 4-Sep-09 0.00613 Christine-Lac du Sauvage 14-Jun-01 <0.00006 1616-43 (KPSF) 21-Sep-09 0.00578 Christine-Lac du Sauvage 14-Jun-01 <0.00006 1616-43 (KPSF) 28-Sep-09 0.00548 Christine-Lac du Sauvage 14-Jun-01 <0.00006 1616-43 (KPSF) 8-Jun-10 0.00167 Christine-Lac du Sauvage 7-Aug-01 <0.00006 1616-43 (KPSF) 8-Jun-10 0.00155 Christine-Lac du Sauvage 7-Aug-01 <0.00006 1616-43 (KPSF) 5-Jul-10 0.00372 Christine-Lac du Sauvage 7-Aug-01 <0.00006 1616-43 (KPSF) 5-Jul-10 0.00377 Christine-Lac du Sauvage 8-Sep-01 <0.00006 1616-43 (KPSF) 1-Aug-10 0.00441 Christine-Lac du Sauvage 8-Sep-01 <0.00006 1616-43 (KPSF) 1-Aug-10 0.00449 Christine-Lac du Sauvage 8-Sep-01 <0.00006 1616-43 (KPSF) 14-Jun-10 0.00235 Christine-Lac du Sauvage 16-Jun-02 <0.00006 1616-43 (KPSF) 14-Jun-10 0.00235 Christine-Lac du Sauvage 16-Jun-02 <0.00006 Christine-Lac du Sauvage 16-Jun-02 <0.00006 Christine-Lac du Sauvage 4-Sep-09 0.000086 Christine-Lac du Sauvage 6-Aug-02 <0.00006 Christine-Lac du Sauvage 4-Sep-09 0.00006 Christine-Lac du Sauvage 6-Aug-02 <0.00006 Christine-Lac du Sauvage 7-Jun-10 <0.000050 Christine-Lac du Sauvage 6-Aug-02 <0.00006 Christine-Lac du Sauvage 7-Jun-10 <0.000050 Christine-Lac du Sauvage 11-Sep-02 <0.00006 Christine-Lac du Sauvage 4-Jul-10 <0.000050 Christine-Lac du Sauvage 11-Sep-02 <0.00006 Christine-Lac du Sauvage 4-Jul-10 <0.000050 Christine-Lac du Sauvage 11-Sep-02 <0.00006 Christine-Lac du Sauvage 1-Aug-10 0.000062 Christine-Lac du Sauvage 12-Jun-03 <0.00006 Christine-Lac du Sauvage 1-Aug-10 0.00006 Christine-Lac du Sauvage 12-Jun-03 <0.00006 Christine-Lac du Sauvage 8-Sep-10 0.000084 Christine-Lac du Sauvage 2-Aug-03 <0.00006 Christine-Lac du Sauvage 8-Sep-10 0.000058 Christine-Lac du Sauvage 2-Aug-03 <0.00006 Christine-Lac du Sauvage 12-Jun-11 0.000063 Christine-Lac du Sauvage 4-Sep-03 <0.00006 Christine-Lac du Sauvage 12-Jun-11 0.000055 Christine-Lac du Sauvage 4-Sep-03 <0.00006 Christine-Lac du Sauvage 3-Jul-11 0.000069 Christine-Lac du Sauvage 20-Jun-04 <0.000050 Christine-Lac du Sauvage 3-Jul-11 0.000063 Christine-Lac du Sauvage 20-Jun-04 <0.000050 Christine-Lac du Sauvage 30-Jul-11 0.00008 Christine-Lac du Sauvage 11-Aug-04 0.000084 Christine-Lac du Sauvage 30-Jul-11 0.000102 Christine-Lac du Sauvage 11-Aug-04 0.000058 Christine-Lac du Sauvage 30-Aug-11 0.000073 Christine-Lac du Sauvage 9-Sep-04 0.000688 Christine-Lac du Sauvage 30-Aug-11 0.000078 Christine-Lac du Sauvage 9-Sep-04 0.000083 Count Outflow 7-Jun-10 <0.000050 Christine-Lac du Sauvage 13-Jun-05 <0.000050 Count Outflow 7-Jun-10 <0.000050 Christine-Lac du Sauvage 13-Jun-05 <0.000050 Count Outflow 12-Jun-11 <0.000050 Christine-Lac du Sauvage 2-Aug-05 0.000054 Count Outflow 12-Jun-11 <0.000050 Christine-Lac du Sauvage 2-Aug-05 <0.000050 Counts Ouflow 1-Aug-10 <0.000050 Christine-Lac du Sauvage 5-Sep-05 <0.000050 Counts Ouflow 1-Aug-10 <0.000050 Christine-Lac du Sauvage 5-Sep-05 <0.000050 Counts Ouflow 30-Jul-11 <0.000050 Christine-Lac du Sauvage 21-May-06 <0.000050 Counts Ouflow 30-Jul-11 <0.000050 Christine-Lac du Sauvage 21-May-06 <0.000050 Counts Outflow 7-Sep-97 <0.00005 Christine-Lac du Sauvage 27-Jul-06 0.000072 Counts Outflow 20-May-98 <0.00006 Christine-Lac du Sauvage 27-Jul-06 <0.000050 Counts Outflow 20-May-98 0.00009 Christine-Lac du Sauvage 2-Sep-06 0.00009 Counts Outflow 20-May-98 <0.00006 Christine-Lac du Sauvage 11-Sep-06 0.000054 Counts Outflow 25-Jun-98 <0.00006 Christine-Lac du Sauvage 5-Sep-07 0.000064 Counts Outflow 22-Jul-98 0.00009 Christine-Lac du Sauvage 5-Sep-07 0.000076 Counts Outflow 22-Jul-98 <0.00006 Christine-Lac du Sauvage 6-Jun-07 0.000061 Counts Outflow 22-Jul-98 <0.00006 Christine-Lac du Sauvage 4-Aug-07 0.000052 Counts Outflow 18-Aug-98 <0.00006

Page 29 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Christine-Lac du Sauvage 4-Aug-07 0.000061 Counts Outflow 18-Aug-98 <0.00006 Christine-Lac du Sauvage 17-Jun-08 <0.000050 Counts Outflow 18-Aug-98 <0.00006 Christine-Lac du Sauvage 17-Jun-08 <0.000050 Counts Outflow 10-Sep-98 <0.00006 Christine-Lac du Sauvage 1-Aug-08 0.00007 Counts Outflow 10-Sep-98 <0.00006 Christine-Lac du Sauvage 1-Aug-08 <0.000050 Counts Outflow 10-Sep-98 <0.00006 Christine-Lac du Sauvage 4-Sep-08 <0.000050 Counts Outflow 4-Jun-99 - Christine-Lac du Sauvage 4-Sep-08 <0.000050 Counts Outflow 4-Jun-99 - Christine-Lac du Sauvage 13-Jun-09 0.000063 Counts Outflow 4-Jun-99 - Christine-Lac du Sauvage 13-Jun-09 0.000061 Counts Outflow 7-Aug-99 - Christine-Lac du Sauvage 3-Aug-09 0.000064 Counts Outflow 7-Aug-99 - Christine-Lac du Sauvage 3-Aug-09 <0.000050 Counts Outflow 7-Aug-99 - Counts Outflow 14-Sep-99 - Counts Outflow 5-Sep-05 <0.000050 Counts Outflow 14-Sep-99 - Counts Outflow 21-May-06 <0.000050 Counts Outflow 14-Sep-99 - Counts Outflow 21-May-06 <0.000050 Counts Outflow 16-Jun-00 <0.00006 Counts Outflow 27-Jul-06 <0.000050 Counts Outflow 16-Jun-00 <0.00006 Counts Outflow 27-Jul-06 <0.000050 Counts Outflow 16-Jun-00 <0.00006 Counts Outflow 31-Aug-06 <0.000050 Counts Outflow 30-Jul-00 <0.00006 Counts Outflow 11-Sep-06 <0.000050 Counts Outflow 30-Jul-00 <0.00006 Counts Outflow 5-Sep-07 <0.000050 Counts Outflow 30-Jul-00 <0.00006 Counts Outflow 5-Sep-07 0.000051 Counts Outflow 7-Sep-00 <0.00006 Counts Outflow 6-Jun-07 <0.000050 Counts Outflow 7-Sep-00 <0.00006 Counts Outflow 3-Aug-07 0.00014 Counts Outflow 7-Sep-00 <0.00006 Counts Outflow 3-Aug-07 <0.000050 Counts Outflow 14-Jun-01 <0.00006 Counts Outflow 17-Jun-08 <0.000050 Counts Outflow 14-Jun-01 <0.00006 Counts Outflow 17-Jun-08 <0.000050 Counts Outflow 7-Aug-01 <0.00006 Counts Outflow 1-Aug-08 <0.000050 Counts Outflow 7-Aug-01 <0.00006 Counts Outflow 1-Aug-08 <0.000050 Counts Outflow 7-Aug-01 <0.00006 Counts Outflow 4-Sep-08 <0.000050 Counts Outflow 8-Sep-01 <0.00006 Counts Outflow 4-Sep-08 <0.000050 Counts Outflow 8-Sep-01 <0.00006 Counts Outflow 21-Jun-09 <0.000050 Counts Outflow 8-Sep-01 <0.00006 Counts Outflow 21-Jun-09 <0.000050 Counts Outflow 16-Jun-02 <0.00006 Counts Outflow 3-Aug-09 <0.000050 Counts Outflow 16-Jun-02 <0.00006 Counts Outflow 3-Aug-09 <0.000050 Counts Outflow 16-Jun-02 <0.00006 Counts Outflow 4-Sep-09 <0.000050 Counts Outflow 6-Aug-02 <0.00006 Counts Outflow 4-Sep-09 <0.000050 Counts Outflow 6-Aug-02 <0.00006 Counts Outflow 4-Jul-10 <0.000050 Counts Outflow 6-Aug-02 <0.00006 Counts Outflow 4-Jul-10 <0.000050 Counts Outflow 11-Sep-02 <0.00006 Counts Outflow 8-Sep-10 <0.000050 Counts Outflow 11-Sep-02 <0.00006 Counts Outflow 8-Sep-10 <0.000050 Counts Outflow 11-Sep-02 <0.00006 Counts Outflow 3-Jul-11 <0.000050 Counts Outflow 12-Jun-03 <0.00006 Counts Outflow 3-Jul-11 <0.000050 Counts Outflow 12-Jun-03 <0.00006 Counts Outflow 30-Aug-11 <0.000050 Counts Outflow 2-Aug-03 <0.00006 Counts Outflow 30-Aug-11 <0.000050 Counts Outflow 2-Aug-03 <0.00006 Cujo Outflow 4-Jun-99 - Counts Outflow 4-Sep-03 <0.00006 Cujo Outflow 4-Jun-99 - Counts Outflow 4-Sep-03 <0.00006 Cujo Outflow 4-Jun-99 - Counts Outflow 20-Jun-04 <0.000050 Cujo Outflow 7-Aug-99 - Counts Outflow 20-Jun-04 <0.000050 Cujo Outflow 7-Aug-99 - Counts Outflow 11-Aug-04 <0.000050 Cujo Outflow 7-Aug-99 - Counts Outflow 11-Aug-04 <0.000050 Cujo Outflow 16-Jun-00 <0.00006 Counts Outflow 9-Sep-04 <0.000050 Cujo Outflow 16-Jun-00 <0.00006 Counts Outflow 9-Sep-04 <0.000050 Cujo Outflow 16-Jun-00 <0.00006 Counts Outflow 13-Jun-05 <0.000050 Cujo Outflow 30-Jul-00 <0.00006 Counts Outflow 13-Jun-05 <0.000050 Cujo Outflow 30-Jul-00 <0.00006 Counts Outflow 2-Aug-05 <0.000050 Cujo Outflow 30-Jul-00 <0.00006

Page 30 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Counts Outflow 2-Aug-05 <0.000050 Cujo Outflow 7-Sep-00 <0.00006 Counts Outflow 5-Sep-05 <0.000050 Cujo Outflow 7-Sep-00 <0.00006 Cujo Outflow 7-Sep-00 <0.00006 Cujo Outflow 4-Aug-07 0.00159 Cujo Outflow 14-Jun-01 <0.00006 Cujo Outflow 4-Aug-07 0.00161 Cujo Outflow 14-Jun-01 <0.00006 Cujo Outflow 17-Jun-08 0.000432 Cujo Outflow 14-Jun-01 <0.00006 Cujo Outflow 17-Jun-08 0.000414 Cujo Outflow 7-Aug-01 <0.00006 Cujo Outflow 1-Aug-08 0.00149 Cujo Outflow 7-Aug-01 <0.00006 Cujo Outflow 1-Aug-08 0.00147 Cujo Outflow 7-Aug-01 <0.00006 Cujo Outflow 4-Sep-08 0.00107 Cujo Outflow 8-Sep-01 0.00016 Cujo Outflow 4-Sep-08 0.00114 Cujo Outflow 8-Sep-01 0.00017 Cujo Outflow 13-Jun-09 0.000329 Cujo Outflow 8-Sep-01 0.00016 Cujo Outflow 13-Jun-09 0.000356 Cujo Outflow 16-Jun-02 0.00019 Cujo Outflow 3-Aug-09 0.000839 Cujo Outflow 16-Jun-02 0.00019 Cujo Outflow 3-Aug-09 0.000883 Cujo Outflow 16-Jun-02 0.00017 Cujo Outflow 4-Sep-09 0.00101 Cujo Outflow 6-Aug-02 0.00028 Cujo Outflow 4-Sep-09 0.000852 Cujo Outflow 6-Aug-02 0.0003 Cujo Outflow 7-Jun-10 0.000378 Cujo Outflow 6-Aug-02 0.0003 Cujo Outflow 7-Jun-10 0.000389 Cujo Outflow 11-Sep-02 0.00105 Cujo Outflow 4-Jul-10 0.000497 Cujo Outflow 11-Sep-02 0.00103 Cujo Outflow 4-Jul-10 0.000505 Cujo Outflow 11-Sep-02 0.00106 Cujo Outflow 1-Aug-10 0.00104 Cujo Outflow 12-Jun-03 0.00039 Cujo Outflow 1-Aug-10 0.00105 Cujo Outflow 12-Jun-03 0.00042 Cujo Outflow 8-Sep-10 0.00151 Cujo Outflow 2-Aug-03 0.00108 Cujo Outflow 8-Sep-10 0.00151 Cujo Outflow 2-Aug-03 0.00109 Cujo Outflow 12-Jun-11 0.000833 Cujo Outflow 4-Sep-03 0.00184 Cujo Outflow 12-Jun-11 0.000842 Cujo Outflow 4-Sep-03 0.00183 Cujo Outflow 2-Jul-11 0.00108 Cujo Outflow 20-Jun-04 0.000278 Cujo Outflow 2-Jul-11 0.00107 Cujo Outflow 20-Jun-04 0.000283 Cujo Outflow 30-Jul-11 0.00147 Cujo Outflow 11-Aug-04 0.000664 Cujo Outflow 30-Jul-11 0.00137 Cujo Outflow 11-Aug-04 0.000661 Cujo Outflow 30-Aug-11 0.00141 Cujo Outflow 9-Sep-04 0.000688 Cujo Outflow 30-Aug-11 0.00136 Cujo Outflow 9-Sep-04 0.000756 Kodiak-Little 12-Jun-94 <0.001 Cujo Outflow 13-Jun-05 0.000383 Kodiak-Little 3-Aug-94 <0.001 Cujo Outflow 13-Jun-05 0.000372 Kodiak-Little 19-Jun-95 <0.001 Cujo Outflow 2-Aug-05 0.00112 Kodiak-Little 8-Aug-95 <0.001 Cujo Outflow 2-Aug-05 0.00114 Kodiak-Little 14-Sep-95 <0.001 Cujo Outflow 5-Sep-05 0.00114 Kodiak-Little 15-Jun-96 0.0001 Cujo Outflow 5-Sep-05 0.00119 Kodiak-Little 28-Jul-96 - Cujo Outflow 21-May-06 0.000271 Kodiak-Little 28-Jul-96 - Cujo Outflow 21-May-06 0.000274 Kodiak-Little 30-May-97 0.00013 Cujo Outflow 27-Jul-06 0.00119 Kodiak-Little 3-Jul-97 0.00013 Cujo Outflow 27-Jul-06 0.00133 Kodiak-Little 6-Sep-97 0.0002 Cujo Outflow 2-Sep-06 0.00283 Kodiak-Little 21-May-98 - Cujo Outflow 11-Sep-06 0.00309 Kodiak-Little 21-May-98 - Cujo Outflow 5-Sep-07 0.00148 Kodiak-Little 21-May-98 - Cujo Outflow 5-Sep-07 0.00147 Kodiak-Little 21-May-98 - Cujo Outflow 6-Jun-07 0.000421 Kodiak-Little 19-Jun-98 - Kodiak-Little 19-Jun-98 - Kodiak-Little 12-Jun-03 0.0001 Kodiak-Little 25-Jun-98 0.00198 Kodiak-Little 12-Jun-03 0.0001 Kodiak-Little 25-Jun-98 0.00205 Kodiak-Little 2-Aug-03 0.00025 Kodiak-Little 25-Jun-98 0.00205 Kodiak-Little 2-Aug-03 0.00016 Kodiak-Little 26-Jun-98 - Kodiak-Little 4-Sep-03 0.00017 Kodiak-Little 14-Jul-98 - Kodiak-Little 4-Sep-03 0.00017 Kodiak-Little 14-Jul-98 - Kodiak-Little 20-Jun-04 0.000079

Page 31 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Kodiak-Little 24-Jul-98 0.00183 Kodiak-Little 20-Jun-04 0.000097 Kodiak-Little 24-Jul-98 0.00178 Kodiak-Little 11-Aug-04 0.00015 Kodiak-Little 24-Jul-98 0.00181 Kodiak-Little 11-Aug-04 0.000168 Kodiak-Little 28-Jul-98 - Kodiak-Little 9-Sep-04 0.000116 Kodiak-Little 11-Aug-98 - Kodiak-Little 9-Sep-04 0.000118 Kodiak-Little 20-Aug-98 <0.00006 Kodiak-Little 13-Jun-05 0.000067 Kodiak-Little 20-Aug-98 0.00129 Kodiak-Little 13-Jun-05 0.000051 Kodiak-Little 20-Aug-98 0.00132 Kodiak-Little 2-Aug-05 0.00012 Kodiak-Little 25-Aug-98 - Kodiak-Little 2-Aug-05 0.000114 Kodiak-Little 18-Sep-98 0.00077 Kodiak-Little 5-Sep-05 0.000117 Kodiak-Little 18-Sep-98 0.00077 Kodiak-Little 5-Sep-05 0.000103 Kodiak-Little 18-Sep-98 0.00077 Kodiak-Little 21-May-06 0.000138 Kodiak-Little 27-Sep-98 - Kodiak-Little 21-May-06 0.000313 Kodiak-Little 6-Jun-99 - Kodiak-Little 29-Jul-06 0.000136 Kodiak-Little 6-Jun-99 - Kodiak-Little 29-Jul-06 0.000125 Kodiak-Little 11-Aug-99 - Kodiak-Little 3-Sep-06 <0.000050 Kodiak-Little 8-Sep-99 - Kodiak-Little 11-Sep-06 0.000223 Kodiak-Little 8-Sep-99 - Kodiak-Little 6-Sep-07 0.000225 Kodiak-Little 8-Jun-00 - Kodiak-Little 6-Sep-07 0.000254 Kodiak-Little 8-Jun-00 - Kodiak-Little 6-Jun-07 0.000142 Kodiak-Little 29-Jul-00 - Kodiak-Little 5-Aug-07 0.00012 Kodiak-Little 29-Jul-00 - Kodiak-Little 5-Aug-07 0.000118 Kodiak-Little 6-Sep-00 - Kodiak-Little 11-Jun-08 0.000113 Kodiak-Little 6-Sep-00 - Kodiak-Little 11-Jun-08 0.000106 Kodiak-Little 14-Jun-01 - Kodiak-Little 1-Aug-08 0.00015 Kodiak-Little 14-Jun-01 - Kodiak-Little 1-Aug-08 0.000159 Kodiak-Little 2-Aug-01 - Kodiak-Little 2-Sep-08 0.000116 Kodiak-Little 2-Aug-01 - Kodiak-Little 3-Sep-08 0.000139 Kodiak-Little 8-Sep-01 - Kodiak-Little 13-Jun-09 0.000101 Kodiak-Little 8-Sep-01 - Kodiak-Little 13-Jun-09 0.000085 Kodiak-Little 16-Jun-02 0.00015 Kodiak-Little 5-Aug-09 0.000095 Kodiak-Little 16-Jun-02 0.00016 Kodiak-Little 5-Aug-09 0.000087 Kodiak-Little 16-Jun-02 0.00015 Kodiak-Little 6-Sep-09 0.000112 Kodiak-Little 6-Aug-02 0.0002 Kodiak-Little 6-Sep-09 0.000111 Kodiak-Little 6-Aug-02 0.00019 Kodiak-Little 7-Jun-10 0.000057 Kodiak-Little 6-Aug-02 0.00018 Kodiak-Little 7-Jun-10 0.000197 Kodiak-Little 11-Sep-02 0.00027 Kodiak-Little 3-Jul-10 0.000088 Kodiak-Little 11-Sep-02 0.00019 Kodiak-Little 3-Jul-10 0.000086 Kodiak-Little 11-Sep-02 0.00017 Kodiak-Little 1-Aug-10 0.000132 Kodiak-Little 8-Sep-10 0.000112 Lower PDC 11-Jun-00 <0.00006 Kodiak-Little 8-Sep-10 0.000123 Lower PDC 30-Jul-00 0.00022 Kodiak-Little 12-Jun-11 0.000102 Lower PDC 30-Jul-00 0.00021 Kodiak-Little 12-Jun-11 0.000092 Lower PDC 30-Jul-00 0.00022 Kodiak-Little 6-Jul-11 0.000121 Lower PDC 8-Sep-00 0.00008 Kodiak-Little 6-Jul-11 0.000121 Lower PDC 8-Sep-00 0.00008 Kodiak-Little 31-Jul-11 0.000137 Lower PDC 8-Sep-00 0.00008 Kodiak-Little 31-Aug-11 0.000141 Lower PDC 14-Jun-01 0.00007 Kodiak-Little 31-Aug-11 0.000144 Lower PDC 14-Jun-01 <0.00006 Kodiak-Little 1-Aug-10 0.000113 Lower PDC 14-Jun-01 <0.00006 Kodiak-Little 31-Jul-11 0.000127 Lower PDC 7-Aug-01 0.0001 Leslie-Moose 7-Jun-10 0.0148 Lower PDC 7-Aug-01 0.00009 Leslie-Moose 7-Jun-10 0.0153 Lower PDC 7-Aug-01 0.0001 Leslie-Moose 3-Jul-10 0.0463 Lower PDC 8-Sep-01 0.0001 Leslie-Moose 3-Jul-10 0.0466 Lower PDC 8-Sep-01 0.00009 Leslie-Moose 1-Aug-10 0.0627 Lower PDC 8-Sep-01 0.0001

Page 32 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Leslie-Moose 1-Aug-10 0.0618 Lower PDC 16-Jun-02 <0.00006 Leslie-Moose 7-Sep-10 0.0631 Lower PDC 16-Jun-02 <0.00006 Leslie-Moose 7-Sep-10 0.0644 Lower PDC 16-Jun-02 0.00013 Leslie-Moose 12-Jun-11 0.0115 Lower PDC 6-Aug-02 0.00008 Leslie-Moose 12-Jun-11 0.0113 Lower PDC 6-Aug-02 0.00009 Leslie-Moose 3-Jul-11 0.054 Lower PDC 6-Aug-02 0.00009 Leslie-Moose 3-Jul-11 0.0531 Lower PDC 11-Sep-02 0.00007 Leslie-Moose 13-Jul-11 0.0565 Lower PDC 11-Sep-02 0.00007 Leslie-Moose 30-Jul-11 0.0612 Lower PDC 11-Sep-02 0.00006 Leslie-Moose 30-Jul-11 0.0717 Lower PDC 12-Jun-03 0.0001 Leslie-Moose 31-Aug-11 0.0743 Lower PDC 12-Jun-03 <0.00006 Leslie-Moose 31-Aug-11 0.074 Lower PDC 2-Aug-03 0.00015 Leslie-Moose 5-Sep-11 0.0779 Lower PDC 2-Aug-03 0.00013 Leslie-Moose 5-Sep-11 0.0745 Lower PDC 4-Sep-03 0.00018 Lower PDC 2-Jun-97 0.0004 Lower PDC 4-Sep-03 0.00014 Lower PDC 2-Jul-97 0.0008 Lower PDC 20-Jun-04 0.000053 Lower PDC 1-Sep-97 0.0004 Lower PDC 20-Jun-04 <0.000050 Lower PDC 20-May-98 - Lower PDC 11-Aug-04 0.00011 Lower PDC 29-Jun-98 - Lower PDC 11-Aug-04 0.000107 Lower PDC 29-Jun-98 - Lower PDC 9-Sep-04 0.000091 Lower PDC 20-Jul-98 - Lower PDC 9-Sep-04 0.000086 Lower PDC 17-Aug-98 - Lower PDC 13-Jun-05 <0.000050 Lower PDC 15-Sep-98 0.0001 Lower PDC 13-Jun-05 <0.000050 Lower PDC 7-Jun-99 - Lower PDC 2-Aug-05 0.000085 Lower PDC 2-Aug-99 - Lower PDC 2-Aug-05 0.000072 Lower PDC 2-Aug-99 - Lower PDC 5-Sep-05 0.000059 Lower PDC 4-Sep-99 - Lower PDC 5-Sep-05 0.000061 Lower PDC 4-Sep-99 - Lower PDC 21-May-06 0.000075 Lower PDC 11-Jun-00 <0.00006 Lower PDC 21-May-06 <0.000050 Lower PDC 11-Jun-00 <0.00006 Lower PDC 29-Jul-06 0.000089 Lower PDC 29-Jul-06 0.000117 Lower PDC 6-Jul-11 0.000104 Lower PDC 2-Sep-06 0.000139 Lower PDC 9-Jul-11 0.000072 Lower PDC 9-Sep-06 0.000152 Lower PDC 12-Jul-11 0.000088 Lower PDC 6-Sep-07 0.000087 Lower PDC 16-Jul-11 0.000081 Lower PDC 6-Sep-07 0.00017 Lower PDC 19-Jul-11 0.000143 Lower PDC 6-Jun-07 0.000071 Lower PDC 23-Jul-11 0.000093 Lower PDC 6-Jun-07 <0.000050 Lower PDC 26-Jul-11 0.000102 Lower PDC 5-Aug-07 0.000086 Lower PDC 30-Jul-11 0.000111 Lower PDC 5-Aug-07 0.000078 Lower PDC 30-Jul-11 0.000089 Lower PDC 16-Jun-08 <0.000050 Lower PDC 31-Jul-11 0.00009 Lower PDC 16-Jun-08 <0.000050 Lower PDC 31-Jul-11 0.000094 Lower PDC 28-Jul-08 0.000053 Lower PDC 6-Aug-11 0.000093 Lower PDC 28-Jul-08 0.000076 Lower PDC 13-Aug-11 0.000088 Lower PDC 2-Sep-08 0.000055 Lower PDC 21-Aug-11 0.000234 Lower PDC 2-Sep-08 <0.000050 Lower PDC 28-Aug-11 0.000128 Lower PDC 13-Jun-09 0.00006 Lower PDC 28-Aug-11 0.000115 Lower PDC 13-Jun-09 0.000066 Lower PDC 30-Aug-11 0.00011 Lower PDC 8-Aug-09 <0.000050 Lower PDC 30-Aug-11 0.000104 Lower PDC 8-Aug-09 <0.000050 Lower PDC 3-Sep-11 0.000109 Lower PDC 5-Sep-09 0.000074 Lower PDC 11-Sep-11 0.000091 Lower PDC 5-Sep-09 0.000062 Lower PDC 18-Sep-11 0.0001 Lower PDC 7-Jun-10 <0.000050 Lower PDC 25-Sep-11 0.000148 Lower PDC 7-Jun-10 <0.000050 Lower PDC 25-Sep-11 0.000085 Lower PDC 7-Jul-10 <0.000050 Moose-Nero 14-Jun-96 0.00006 Lower PDC 7-Jul-10 <0.000050 Moose-Nero 14-Jun-96 0.00006

Page 33 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Lower PDC 2-Aug-10 0.000111 Moose-Nero 27-Jul-96 - Lower PDC 2-Aug-10 0.000112 Moose-Nero 31-May-97 0.00009 Lower PDC 8-Sep-10 0.00008 Moose-Nero 3-Jul-97 0.00006 Lower PDC 8-Sep-10 0.00008 Moose-Nero 5-Sep-97 <0.00005 Lower PDC 4-Jun-11 0.000052 Moose-Nero 5-Sep-97 <0.00005 Lower PDC 7-Jun-11 0.000082 Moose-Nero 23-May-98 0.00229 Lower PDC 11-Jun-11 0.000067 Moose-Nero 23-May-98 0.0213 Lower PDC 11-Jun-11 0.000071 Moose-Nero 23-May-98 0.00219 Lower PDC 12-Jun-11 0.000055 Moose-Nero 27-Jun-98 0.00064 Lower PDC 12-Jun-11 0.000053 Moose-Nero 21-Jul-98 0.00069 Lower PDC 14-Jun-11 0.000148 Moose-Nero 21-Jul-98 0.00068 Lower PDC 16-Jun-11 0.00009 Moose-Nero 21-Jul-98 0.00067 Lower PDC 18-Jun-11 0.000088 Moose-Nero 16-Aug-98 0.00018 Lower PDC 21-Jun-11 0.000089 Moose-Nero 16-Aug-98 0.00018 Lower PDC 25-Jun-11 0.000076 Moose-Nero 16-Aug-98 0.00017 Lower PDC 27-Jun-11 0.000075 Moose-Nero 17-Sep-98 0.0002 Lower PDC 2-Jul-11 0.00016 Moose-Nero 17-Sep-98 0.00027 Lower PDC 2-Jul-11 0.00015 Moose-Nero 17-Sep-98 0.00022 Lower PDC 3-Jul-11 0.000148 Moose-Nero 3-Jun-99 - Lower PDC 3-Jul-11 0.00015 Moose-Nero 3-Jun-99 - Lower PDC 5-Jul-11 0.000119 Moose-Nero 3-Jun-99 - Moose-Nero 8-Aug-99 - Moose-Nero 13-Jun-05 0.0145 Moose-Nero 8-Aug-99 - Moose-Nero 2-Aug-05 0.0153 Moose-Nero 8-Aug-99 - Moose-Nero 2-Aug-05 0.0154 Moose-Nero 15-Sep-99 - Moose-Nero 5-Sep-05 0.00956 Moose-Nero 15-Sep-99 - Moose-Nero 5-Sep-05 0.00926 Moose-Nero 15-Sep-99 - Moose-Nero 21-May-06 0.00332 Moose-Nero 10-Jun-00 0.00065 Moose-Nero 21-May-06 0.00325 Moose-Nero 10-Jun-00 0.00056 Moose-Nero 27-Jul-06 0.0482 Moose-Nero 10-Jun-00 0.00055 Moose-Nero 27-Jul-06 0.0498 Moose-Nero 29-Jul-00 0.00186 Moose-Nero 1-Sep-06 0.0341 Moose-Nero 29-Jul-00 0.00182 Moose-Nero 11-Sep-06 0.0628 Moose-Nero 29-Jul-00 0.00182 Moose-Nero 6-Sep-07 0.06 Moose-Nero 6-Sep-00 0.00221 Moose-Nero 6-Sep-07 0.0593 Moose-Nero 6-Sep-00 0.00222 Moose-Nero 6-Jun-07 0.0027 Moose-Nero 6-Sep-00 0.00221 Moose-Nero 3-Aug-07 0.0504 Moose-Nero 14-Jun-01 0.00213 Moose-Nero 3-Aug-07 0.0486 Moose-Nero 14-Jun-01 0.00215 Moose-Nero 18-Jun-08 0.00865 Moose-Nero 14-Jun-01 0.00219 Moose-Nero 18-Jun-08 0.00843 Moose-Nero 7-Aug-01 0.00335 Moose-Nero 1-Aug-08 0.0162 Moose-Nero 7-Aug-01 0.00342 Moose-Nero 1-Aug-08 0.0163 Moose-Nero 7-Aug-01 0.00344 Moose-Nero 3-Sep-08 0.0116 Moose-Nero 8-Sep-01 0.00529 Moose-Nero 3-Sep-08 0.0116 Moose-Nero 8-Sep-01 0.00542 Moose-Nero 13-Jun-09 0.0063 Moose-Nero 8-Sep-01 0.00545 Moose-Nero 13-Jun-09 0.00686 Moose-Nero 16-Jun-02 0.00075 Moose-Nero 5-Aug-09 0.0409 Moose-Nero 16-Jun-02 0.00074 Moose-Nero 5-Aug-09 0.0417 Moose-Nero 16-Jun-02 0.00075 Moose-Nero 6-Sep-09 0.0448 Moose-Nero 6-Aug-02 0.00608 Moose-Nero 6-Sep-09 0.0461 Moose-Nero 6-Aug-02 0.00603 Moose-Nero 7-Jun-10 0.00465 Moose-Nero 6-Aug-02 0.00611 Moose-Nero 7-Jun-10 0.00454 Moose-Nero 11-Sep-02 0.00342 Moose-Nero 3-Jul-10 0.0106 Moose-Nero 11-Sep-02 0.00339 Moose-Nero 3-Jul-10 0.0106 Moose-Nero 11-Sep-02 0.00339 Moose-Nero 1-Aug-10 0.0442 Moose-Nero 12-Jun-03 0.00082 Moose-Nero 1-Aug-10 0.0438

Page 34 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Moose-Nero 12-Jun-03 0.00082 Moose-Nero 7-Sep-10 0.0478 Moose-Nero 2-Aug-03 0.00555 Moose-Nero 7-Sep-10 0.0475 Moose-Nero 2-Aug-03 0.00554 Moose-Nero 12-Jun-11 0.00408 Moose-Nero 4-Sep-03 0.00835 Moose-Nero 12-Jun-11 0.00407 Moose-Nero 4-Sep-03 0.00829 Moose-Nero 3-Jul-11 0.0168 Moose-Nero 3-Jul-04 0.00298 Moose-Nero 3-Jul-11 0.0163 Moose-Nero 3-Jul-04 0.00302 Moose-Nero 13-Jul-11 0.0216 Moose-Nero 11-Aug-04 0.0185 Moose-Nero 30-Jul-11 0.0571 Moose-Nero 11-Aug-04 0.0184 Moose-Nero 30-Jul-11 0.0561 Moose-Nero 9-Sep-04 0.0231 Moose-Nero 31-Aug-11 0.0438 Moose-Nero 9-Sep-04 0.0236 Moose-Nero 31-Aug-11 0.0439 Moose-Nero 13-Jun-05 0.0143 Moose-Nero 5-Sep-11 0.0383 Nanuq Outflow 7-Sep-97 <0.00005 Nanuq Outflow 6-Aug-02 <0.00006 Nanuq Outflow 20-May-98 <0.00006 Nanuq Outflow 11-Sep-02 <0.00006 Nanuq Outflow 20-May-98 <0.00006 Nanuq Outflow 11-Sep-02 <0.00006 Nanuq Outflow 20-May-98 <0.00006 Nanuq Outflow 11-Sep-02 <0.00006 Nanuq Outflow 25-Jun-98 <0.00006 Nanuq Outflow 12-Jun-03 <0.00006 Nanuq Outflow 22-Jul-98 <0.00006 Nanuq Outflow 12-Jun-03 <0.00006 Nanuq Outflow 22-Jul-98 <0.00006 Nanuq Outflow 2-Aug-03 <0.00006 Nanuq Outflow 22-Jul-98 <0.00006 Nanuq Outflow 2-Aug-03 <0.00006 Nanuq Outflow 18-Aug-98 <0.00006 Nanuq Outflow 4-Sep-03 <0.00006 Nanuq Outflow 18-Aug-98 <0.00006 Nanuq Outflow 4-Sep-03 <0.00006 Nanuq Outflow 18-Aug-98 <0.00006 Nanuq Outflow 20-Jun-04 <0.000050 Nanuq Outflow 9-Sep-98 <0.00006 Nanuq Outflow 20-Jun-04 <0.000050 Nanuq Outflow 9-Sep-98 <0.00006 Nanuq Outflow 11-Aug-04 <0.000050 Nanuq Outflow 9-Sep-98 <0.00006 Nanuq Outflow 11-Aug-04 <0.000050 Nanuq Outflow 4-Jun-99 - Nanuq Outflow 9-Sep-04 <0.000050 Nanuq Outflow 4-Jun-99 - Nanuq Outflow 9-Sep-04 0.00007 Nanuq Outflow 4-Jun-99 - Nanuq Outflow 13-Jun-05 <0.000050 Nanuq Outflow 6-Aug-99 - Nanuq Outflow 13-Jun-05 <0.000050 Nanuq Outflow 6-Aug-99 - Nanuq Outflow 2-Aug-05 <0.000050 Nanuq Outflow 6-Aug-99 - Nanuq Outflow 2-Aug-05 <0.000050 Nanuq Outflow 14-Sep-99 - Nanuq Outflow 5-Sep-05 0.000054 Nanuq Outflow 14-Sep-99 - Nanuq Outflow 5-Sep-05 <0.000050 Nanuq Outflow 14-Sep-99 - Nanuq Outflow 21-May-06 <0.000050 Nanuq Outflow 16-Jun-00 <0.00006 Nanuq Outflow 21-May-06 <0.000050 Nanuq Outflow 16-Jun-00 <0.00006 Nanuq Outflow 27-Jul-06 <0.000050 Nanuq Outflow 16-Jun-00 <0.00006 Nanuq Outflow 27-Jul-06 <0.000050 Nanuq Outflow 30-Jul-00 <0.00006 Nanuq Outflow 31-Aug-06 <0.000050 Nanuq Outflow 30-Jul-00 <0.00006 Nanuq Outflow 11-Sep-06 <0.000050 Nanuq Outflow 30-Jul-00 <0.00006 Nanuq Outflow 6-Sep-07 <0.000050 Nanuq Outflow 8-Sep-00 <0.00006 Nanuq Outflow 6-Sep-07 <0.000050 Nanuq Outflow 8-Sep-00 <0.00006 Nanuq Outflow 16-Jun-07 <0.000050 Nanuq Outflow 8-Sep-00 <0.00006 Nanuq Outflow 3-Aug-07 <0.000050 Nanuq Outflow 14-Jun-01 <0.00006 Nanuq Outflow 3-Aug-07 0.000094 Nanuq Outflow 14-Jun-01 <0.00006 Nanuq Outflow 17-Jun-08 <0.000050 Nanuq Outflow 14-Jun-01 <0.00006 Nanuq Outflow 17-Jun-08 <0.000050 Nanuq Outflow 7-Aug-01 <0.00006 Nanuq Outflow 2-Aug-08 <0.000050 Nanuq Outflow 7-Aug-01 <0.00006 Nanuq Outflow 2-Aug-08 <0.000050 Nanuq Outflow 7-Aug-01 <0.00006 Nanuq Outflow 4-Sep-08 <0.000050 Nanuq Outflow 8-Sep-01 <0.00006 Nanuq Outflow 4-Sep-08 <0.000050 Nanuq Outflow 8-Sep-01 <0.00006 Nanuq Outflow 21-Jun-09 <0.000050 Nanuq Outflow 8-Sep-01 <0.00006 Nanuq Outflow 21-Jun-09 <0.000050 Nanuq Outflow 16-Jun-02 <0.00006 Nanuq Outflow 3-Aug-09 <0.000050 Nanuq Outflow 16-Jun-02 <0.00006 Nanuq Outflow 3-Aug-09 <0.000050

Page 35 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Nanuq Outflow 16-Jun-02 <0.00006 Nanuq Outflow 4-Sep-09 <0.000050 Nanuq Outflow 6-Aug-02 <0.00006 Nanuq Outflow 4-Sep-09 <0.000050 Nanuq Outflow 6-Aug-02 <0.00006 Nanuq Outflow 13-Jun-10 <0.000050 Nanuq Outflow 13-Jun-10 <0.000050 Nema-Martine 10-Jun-00 0.00019 Nanuq Outflow 3-Jul-10 <0.000050 Nema-Martine 10-Jun-00 0.00019 Nanuq Outflow 3-Jul-10 <0.000050 Nema-Martine 29-Jul-00 0.00039 Nanuq Outflow 1-Aug-10 <0.000050 Nema-Martine 29-Jul-00 0.00039 Nanuq Outflow 1-Aug-10 <0.000050 Nema-Martine 29-Jul-00 0.00039 Nanuq Outflow 8-Sep-10 <0.000050 Nema-Martine 6-Sep-00 0.00051 Nanuq Outflow 8-Sep-10 <0.000050 Nema-Martine 6-Sep-00 0.0005 Nanuq Outflow 12-Jun-11 <0.000050 Nema-Martine 6-Sep-00 0.0005 Nanuq Outflow 12-Jun-11 <0.000050 Nema-Martine 14-Jun-01 0.00038 Nanuq Outflow 3-Jul-11 <0.000050 Nema-Martine 14-Jun-01 0.00036 Nanuq Outflow 3-Jul-11 <0.000050 Nema-Martine 14-Jun-01 0.00035 Nanuq Outflow 30-Jul-11 <0.000050 Nema-Martine 7-Aug-01 0.00111 Nanuq Outflow 30-Jul-11 <0.000050 Nema-Martine 7-Aug-01 0.00109 Nanuq Outflow 30-Aug-11 <0.000050 Nema-Martine 7-Aug-01 0.00109 Nanuq Outflow 30-Aug-11 <0.000050 Nema-Martine 8-Sep-01 0.00183 Nema-Martine 18-Jun-95 <0.001 Nema-Martine 8-Sep-01 0.0018 Nema-Martine 10-Aug-95 <0.001 Nema-Martine 8-Sep-01 0.00178 Nema-Martine 13-Sep-95 <0.001 Nema-Martine 16-Jun-02 0.0012 Nema-Martine 14-Jun-96 0.00006 Nema-Martine 16-Jun-02 0.0012 Nema-Martine 26-Jul-96 - Nema-Martine 16-Jun-02 0.00121 Nema-Martine 30-May-97 0.00007 Nema-Martine 6-Aug-02 0.00182 Nema-Martine 4-Jul-97 0.00006 Nema-Martine 6-Aug-02 0.00172 Nema-Martine 5-Sep-97 <0.00005 Nema-Martine 6-Aug-02 0.00177 Nema-Martine 23-May-98 0.00045 Nema-Martine 11-Sep-02 0.00206 Nema-Martine 23-May-98 0.00043 Nema-Martine 11-Sep-02 0.00206 Nema-Martine 23-May-98 0.00044 Nema-Martine 11-Sep-02 0.00203 Nema-Martine 26-Jun-98 0.00041 Nema-Martine 12-Jun-03 0.001 Nema-Martine 25-Jul-98 0.00053 Nema-Martine 12-Jun-03 0.00105 Nema-Martine 25-Jul-98 0.00035 Nema-Martine 2-Aug-03 0.00181 Nema-Martine 25-Jul-98 0.00033 Nema-Martine 2-Aug-03 0.00177 Nema-Martine 21-Aug-98 0.00028 Nema-Martine 4-Sep-03 0.00173 Nema-Martine 21-Aug-98 0.00026 Nema-Martine 4-Sep-03 0.00173 Nema-Martine 21-Aug-98 0.00028 Nema-Martine 20-Jun-04 0.00434 Nema-Martine 17-Sep-98 0.00021 Nema-Martine 20-Jun-04 0.00459 Nema-Martine 17-Sep-98 0.00021 Nema-Martine 11-Aug-04 0.00782 Nema-Martine 17-Sep-98 0.00021 Nema-Martine 11-Aug-04 0.00746 Nema-Martine 3-Jun-99 - Nema-Martine 9-Sep-04 0.00866 Nema-Martine 3-Jun-99 - Nema-Martine 9-Sep-04 0.00839 Nema-Martine 3-Jun-99 - Nema-Martine 13-Jun-05 0.00741 Nema-Martine 7-Aug-99 - Nema-Martine 13-Jun-05 0.00748 Nema-Martine 7-Aug-99 - Nema-Martine 2-Aug-05 0.0209 Nema-Martine 7-Aug-99 - Nema-Martine 2-Aug-05 0.0208 Nema-Martine 16-Sep-99 - Nema-Martine 5-Sep-05 0.0192 Nema-Martine 16-Sep-99 - Nema-Martine 5-Sep-05 0.0189 Nema-Martine 16-Sep-99 - Nema-Martine 21-May-06 0.00516 Nema-Martine 10-Jun-00 0.00019 Nema-Martine 21-May-06 0.00514 Nema-Martine 27-Jul-06 0.0193 Slipper-Lac de Gras 5-Jul-97 <0.00005 Nema-Martine 27-Jul-06 0.0194 Slipper-Lac de Gras 4-Sep-97 0.00005 Nema-Martine 3-Sep-06 0.0186 Slipper-Lac de Gras 23-May-98 <0.00006 Nema-Martine 11-Sep-06 0.0192 Slipper-Lac de Gras 23-May-98 <0.00006 Nema-Martine 6-Sep-07 0.0291 Slipper-Lac de Gras 23-May-98 <0.00006 Nema-Martine 6-Sep-07 0.028 Slipper-Lac de Gras 26-Jun-98 0.00007

Page 36 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Nema-Martine 6-Jun-07 0.0109 Slipper-Lac de Gras 23-Jul-98 0.0001 Nema-Martine 4-Aug-07 0.0222 Slipper-Lac de Gras 23-Jul-98 0.00009 Nema-Martine 4-Aug-07 0.022 Slipper-Lac de Gras 23-Jul-98 0.00009 Nema-Martine 18-Jun-08 0.013 Slipper-Lac de Gras 19-Aug-98 0.00008 Nema-Martine 18-Jun-08 0.0128 Slipper-Lac de Gras 19-Aug-98 0.00009 Nema-Martine 1-Aug-08 0.0254 Slipper-Lac de Gras 19-Aug-98 0.00008 Nema-Martine 1-Aug-08 0.0261 Slipper-Lac de Gras 17-Sep-98 0.00008 Nema-Martine 3-Sep-08 0.0232 Slipper-Lac de Gras 17-Sep-98 0.00007 Nema-Martine 3-Sep-08 0.0227 Slipper-Lac de Gras 17-Sep-98 0.00007 Nema-Martine 13-Jun-09 0.0162 Slipper-Lac de Gras 3-Jun-99 - Nema-Martine 13-Jun-09 0.0165 Slipper-Lac de Gras 3-Jun-99 - Nema-Martine 4-Aug-09 0.0163 Slipper-Lac de Gras 3-Jun-99 - Nema-Martine 4-Aug-09 0.0168 Slipper-Lac de Gras 7-Aug-99 - Nema-Martine 6-Sep-09 0.0173 Slipper-Lac de Gras 7-Aug-99 - Nema-Martine 6-Sep-09 0.018 Slipper-Lac de Gras 7-Aug-99 - Nema-Martine 7-Jun-10 0.00937 Slipper-Lac de Gras 15-Sep-99 - Nema-Martine 7-Jun-10 0.00912 Slipper-Lac de Gras 15-Sep-99 - Nema-Martine 3-Jul-10 0.0112 Slipper-Lac de Gras 15-Sep-99 - Nema-Martine 3-Jul-10 0.0111 Slipper-Lac de Gras 10-Jun-00 0.00012 Nema-Martine 1-Aug-10 0.0174 Slipper-Lac de Gras 10-Jun-00 0.00012 Nema-Martine 7-Sep-10 0.0164 Slipper-Lac de Gras 10-Jun-00 0.00012 Nema-Martine 7-Sep-10 0.0159 Slipper-Lac de Gras 29-Jul-00 0.00012 Nema-Martine 1-Aug-10 0.0179 Slipper-Lac de Gras 29-Jul-00 0.00013 Nema-Martine 12-Jun-11 0.00536 Slipper-Lac de Gras 29-Jul-00 0.00012 Nema-Martine 12-Jun-11 0.00522 Slipper-Lac de Gras 6-Sep-00 0.00012 Nema-Martine 3-Jul-11 0.0122 Slipper-Lac de Gras 6-Sep-00 0.00011 Nema-Martine 3-Jul-11 0.012 Slipper-Lac de Gras 6-Sep-00 0.00012 Nema-Martine 13-Jul-11 0.0144 Slipper-Lac de Gras 14-Jun-01 0.00025 Nema-Martine 30-Jul-11 0.0193 Slipper-Lac de Gras 14-Jun-01 0.00023 Nema-Martine 30-Jul-11 0.0196 Slipper-Lac de Gras 14-Jun-01 0.00024 Nema-Martine 31-Aug-11 0.0249 Slipper-Lac de Gras 7-Aug-01 0.00024 Nema-Martine 31-Aug-11 0.0249 Slipper-Lac de Gras 7-Aug-01 0.00024 Nema-Martine 5-Sep-11 0.0253 Slipper-Lac de Gras 7-Aug-01 0.00024 Slipper-Lac de Gras 9-Aug-94 <0.001 Slipper-Lac de Gras 8-Sep-01 0.00022 Slipper-Lac de Gras 18-Jun-95 <0.001 Slipper-Lac de Gras 8-Sep-01 0.00023 Slipper-Lac de Gras 18-Jun-95 <0.001 Slipper-Lac de Gras 8-Sep-01 0.00023 Slipper-Lac de Gras 10-Aug-95 <0.001 Slipper-Lac de Gras 16-Jun-02 0.00021 Slipper-Lac de Gras 13-Sep-95 <0.001 Slipper-Lac de Gras 16-Jun-02 0.0002 Slipper-Lac de Gras 14-Jun-96 <0.00005 Slipper-Lac de Gras 16-Jun-02 0.00021 Slipper-Lac de Gras 26-Jul-96 - Slipper-Lac de Gras 6-Aug-02 0.00034 Slipper-Lac de Gras 6-Aug-02 0.00033 Slipper-Lac de Gras 7-Jun-10 0.00235 Slipper-Lac de Gras 6-Aug-02 0.00033 Slipper-Lac de Gras 7-Jun-10 0.00236 Slipper-Lac de Gras 11-Sep-02 0.00046 Slipper-Lac de Gras 4-Jul-10 0.00295 Slipper-Lac de Gras 11-Sep-02 0.00045 Slipper-Lac de Gras 4-Jul-10 0.00291 Slipper-Lac de Gras 11-Sep-02 0.00047 Slipper-Lac de Gras 1-Aug-10 0.00514 Slipper-Lac de Gras 12-Jun-03 0.0004 Slipper-Lac de Gras 1-Aug-10 0.00517 Slipper-Lac de Gras 12-Jun-03 0.0004 Slipper-Lac de Gras 7-Sep-10 0.00537 Slipper-Lac de Gras 2-Aug-03 0.00052 Slipper-Lac de Gras 7-Sep-10 0.00553 Slipper-Lac de Gras 2-Aug-03 0.00054 Slipper-Lac de Gras 12-Jun-11 0.00259 Slipper-Lac de Gras 4-Sep-03 0.00052 Slipper-Lac de Gras 12-Jun-11 0.00264 Slipper-Lac de Gras 4-Sep-03 0.00051 Slipper-Lac de Gras 4-Jul-11 0.00364 Slipper-Lac de Gras 20-Jun-04 0.00413 Slipper-Lac de Gras 4-Jul-11 0.00354 Slipper-Lac de Gras 20-Jun-04 0.00413 Slipper-Lac de Gras 13-Jul-11 0.00429 Slipper-Lac de Gras 11-Aug-04 0.00189 Slipper-Lac de Gras 30-Jul-11 0.00466 Slipper-Lac de Gras 11-Aug-04 0.00183 Slipper-Lac de Gras 30-Jul-11 0.00464

Page 37 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Slipper-Lac de Gras 9-Sep-04 0.00159 Slipper-Lac de Gras 31-Aug-11 0.00633 Slipper-Lac de Gras 9-Sep-04 0.00156 Slipper-Lac de Gras 31-Aug-11 0.0064 Slipper-Lac de Gras 13-Jun-05 0.00344 Slipper-Lac de Gras 4-Sep-11 0.00698 Slipper-Lac de Gras 13-Jun-05 0.00343 Vulture Outflow 8-Jun-10 <0.000050 Slipper-Lac de Gras 2-Aug-05 0.00506 Vulture Outflow 8-Jun-10 <0.000050 Slipper-Lac de Gras 2-Aug-05 0.00512 Vulture Outflow 5-Jul-10 <0.000050 Slipper-Lac de Gras 5-Sep-05 0.00498 Vulture Outflow 5-Jul-10 <0.000050 Slipper-Lac de Gras 5-Sep-05 0.00512 Vulture Outflow 1-Aug-10 <0.000050 Slipper-Lac de Gras 21-May-06 0.0025 Vulture Outflow 1-Aug-10 <0.000050 Slipper-Lac de Gras 21-May-06 0.00251 Vulture Outflow 8-Sep-10 <0.000050 Slipper-Lac de Gras 28-Jul-06 0.00419 Vulture Outflow 8-Sep-10 <0.000050 Slipper-Lac de Gras 28-Jul-06 0.00425 Vulture Outflow 12-Jun-11 <0.000050 Slipper-Lac de Gras 1-Sep-06 0.00515 Vulture Outflow 12-Jun-11 <0.000050 Slipper-Lac de Gras 11-Sep-06 0.00525 Vulture Outflow 3-Jul-11 <0.000050 Slipper-Lac de Gras 6-Sep-07 0.005 Vulture Outflow 3-Jul-11 <0.000050 Slipper-Lac de Gras 6-Sep-07 0.00483 Vulture Outflow 31-Jul-11 <0.000050 Slipper-Lac de Gras 6-Jun-07 0.00732 Vulture Outflow 31-Jul-11 <0.000050 Slipper-Lac de Gras 4-Aug-07 0.00477 Vulture Outflow 31-Aug-11 <0.000050 Slipper-Lac de Gras 4-Aug-07 0.00468 Vulture Outflow 31-Aug-11 <0.000050 Slipper-Lac de Gras 17-Jun-08 0.00467 Vulture-Polar 18-Jun-08 0.000144 Slipper-Lac de Gras 17-Jun-08 0.00476 Vulture-Polar 18-Jun-08 <0.000050 Slipper-Lac de Gras 1-Aug-08 0.00549 Vulture-Polar 2-Aug-08 <0.000050 Slipper-Lac de Gras 1-Aug-08 0.00551 Vulture-Polar 2-Aug-08 <0.000050 Slipper-Lac de Gras 3-Sep-08 0.00507 Vulture-Polar 5-Sep-08 <0.000050 Slipper-Lac de Gras 3-Sep-08 0.00521 Vulture-Polar 5-Sep-08 <0.000050 Slipper-Lac de Gras 13-Jun-09 0.00683 Vulture-Polar 13-Jun-09 <0.000050 Slipper-Lac de Gras 13-Jun-09 0.00643 Vulture-Polar 13-Jun-09 <0.000050 Slipper-Lac de Gras 4-Aug-09 0.00463 Vulture-Polar 4-Aug-09 <0.000050 Slipper-Lac de Gras 4-Aug-09 0.00515 Vulture-Polar 4-Aug-09 <0.000050 Slipper-Lac de Gras 6-Sep-09 0.00499 Vulture-Polar 4-Sep-09 <0.000050 Slipper-Lac de Gras 6-Sep-09 0.00501 Vulture-Polar 4-Sep-09 <0.000050 Vulture-Polar 13-Jun-94 <0.001 Vulture-Polar 7-Aug-01 <0.00006 Vulture-Polar 13-Jun-94 <0.001 Vulture-Polar 7-Aug-01 <0.00006 Vulture-Polar 13-Jun-94 <0.001 Vulture-Polar 8-Sep-01 <0.00006 Vulture-Polar 4-Aug-94 <0.001 Vulture-Polar 8-Sep-01 <0.00006 Vulture-Polar 6-Jul-95 <0.001 Vulture-Polar 8-Sep-01 <0.00006 Vulture-Polar 10-Aug-95 <0.001 Vulture-Polar 16-Jun-02 <0.00006 Vulture-Polar 14-Sep-95 <0.001 Vulture-Polar 16-Jun-02 0.00086 Vulture-Polar 15-Jun-96 <0.00005 Vulture-Polar 16-Jun-02 <0.00006 Vulture-Polar 27-Jul-96 - Vulture-Polar 6-Aug-02 <0.00006 Vulture-Polar 2-Jul-97 <0.00005 Vulture-Polar 6-Aug-02 <0.00006 Vulture-Polar 6-Sep-97 <0.00005 Vulture-Polar 6-Aug-02 <0.00006 Vulture-Polar 22-May-98 <0.00006 Vulture-Polar 11-Sep-02 <0.00006 Vulture-Polar 22-May-98 <0.00006 Vulture-Polar 11-Sep-02 <0.00006 Vulture-Polar 22-May-98 <0.00006 Vulture-Polar 11-Sep-02 <0.00006 Vulture-Polar 25-Jun-98 <0.00006 Vulture-Polar 12-Jun-03 <0.00006 Vulture-Polar 20-Jul-98 <0.00006 Vulture-Polar 12-Jun-03 <0.00006 Vulture-Polar 20-Jul-98 <0.00006 Vulture-Polar 2-Aug-03 <0.00006 Vulture-Polar 20-Jul-98 <0.00006 Vulture-Polar 2-Aug-03 <0.00006 Vulture-Polar 16-Aug-98 <0.00006 Vulture-Polar 4-Sep-03 <0.00006 Vulture-Polar 16-Aug-98 <0.00006 Vulture-Polar 4-Sep-03 <0.00006 Vulture-Polar 16-Aug-98 <0.00006 Vulture-Polar 20-Jun-04 <0.000050 Vulture-Polar 15-Sep-98 <0.00006 Vulture-Polar 20-Jun-04 <0.000050 Vulture-Polar 15-Sep-98 <0.00006 Vulture-Polar 11-Aug-04 <0.000050 Vulture-Polar 15-Sep-98 <0.00006 Vulture-Polar 11-Aug-04 <0.000050

Page 38 of 39 Appendix A. Molybdenum Water Concentrations in Lakes and Streams of the EKATI Project Area, 1994-2009 Stream Date Molybdenum Stream Date Molybdenum Vulture-Polar 4-Jun-99 - Vulture-Polar 9-Sep-04 <0.000050 Vulture-Polar 4-Jun-99 - Vulture-Polar 9-Sep-04 <0.000050 Vulture-Polar 4-Jun-99 - Vulture-Polar 13-Jun-05 <0.000050 Vulture-Polar 8-Aug-99 - Vulture-Polar 13-Jun-05 <0.000050 Vulture-Polar 8-Aug-99 - Vulture-Polar 2-Aug-05 <0.000050 Vulture-Polar 8-Aug-99 - Vulture-Polar 2-Aug-05 <0.000050 Vulture-Polar 16-Sep-99 - Vulture-Polar 5-Sep-05 <0.000050 Vulture-Polar 16-Sep-99 - Vulture-Polar 5-Sep-05 <0.000050 Vulture-Polar 16-Sep-99 - Vulture-Polar 21-May-06 <0.000050 Vulture-Polar 11-Jun-00 <0.00006 Vulture-Polar 21-May-06 <0.000050 Vulture-Polar 11-Jun-00 <0.00006 Vulture-Polar 27-Jul-06 <0.000050 Vulture-Polar 11-Jun-00 <0.00006 Vulture-Polar 27-Jul-06 <0.000050 Vulture-Polar 30-Jul-00 <0.00006 Vulture-Polar 3-Sep-06 <0.000050 Vulture-Polar 30-Jul-00 <0.00006 Vulture-Polar 11-Sep-06 <0.000050 Vulture-Polar 30-Jul-00 <0.00006 Vulture-Polar 5-Sep-07 0.000092 Vulture-Polar 8-Sep-00 <0.00006 Vulture-Polar 5-Sep-07 <0.00020 Vulture-Polar 8-Sep-00 <0.00006 Vulture-Polar 6-Jun-07 <0.000050 Vulture-Polar 8-Sep-00 <0.00006 Vulture-Polar 4-Aug-07 <0.000050 Vulture-Polar 14-Jun-01 <0.00006 Vulture-Polar 4-Aug-07 <0.000050 Vulture-Polar 14-Jun-01 <0.00006 Vulture-Polar 14-Jun-01 <0.00006 Vulture-Polar 7-Aug-01 <0.00006 Dashes indicate that no analyses or information is available. < indicates less than the detection limit

Page 39 of 39 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Appendix B Acute Toxicity Studies on Molybdenum Available From the Literature

Appendix B. Acute Toxicity Studies on Molybdenum Available From the Literature

Species Geometric Mean Group Species (common name) Endpoint Effect Level Value (mg/L) (mg/L) Molybdenum species Reference Rationale for Acceptability Standardized Method Standardized AppropriateReplication Design and Measured Concentrations ofSensitive Use Lifestages ControlPerformance Factors Abiotic Report Dose- Acceptable response Procedures Statistical ACUTE TESTS INCLUDED FROM THE DATA SET (Primary and Secondary Studies) PROTISTS / ALGAE / PLANTS Phototrophic Protist Euglena gracilis Mortality 24-hr MATC 678.8 678.8 sodium molybdate or Colmano 1973 Partial Yes No Yes Yes Yes Yes No Euglena are present at EKATI. MATC based on geometric mean of LOEC (960 mg/L; 100% (Protist) ammonium dimolybdate stopped growth) and NOEC (480 mg/L; no reported effect). Used two chemicals as molybdenum source. Secondary study as nominal concentrations used.

INVERTEBRATES Invertebrates (benthic) Chironomus tentans Mortality 48-hr LC50 7,533.3 7,533.3 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Chironomids are found at EKATI. Acute LC50 calculated as the geometric mean of two (Midge) LC50 replicates (7,532 and 7,534.7 mg/L). Primary study.

Invertebrates (benthic) Girardia dorotocephala Mortality 96-hr LC50 1,225.6 1,225.6 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Turbellarian worms are found at EKATI, so Girardia is a good surrogate. Value used (Flatworm) based on the geometric mean of two LC50 replicates (1,125.8 and 1,334.2 mg/L). Primary study.

Invertebrates (benthic) Tubifex tubifex Mortality 48-hr EC50 52.12 52.12 sodium molybdate Khangarot 1991 Yes Yes No Yes Yes Yes Yes Yes Tubificids are present in some lakes and streams at EKATI. The 95% CL for the 48-hr (Oligochaete) LC50 were 42.48 to 65.64 mg/L. The 24hr LC50 reported was 56.11 mg/L (95% CL 44.42 to 75.44 mg/L) and the 96-hr LC50 was 28.91 mg/L (95% CL 26.30 to 34.72 mg/L). Secondary study as nominal concentrations used.

Invertebrates (benthic) Crangonyx pseudogracilis Mortality 96-hr LC50 2,650.0 2,650.0 sodium molybdate Martin and Yes Yes No Yes Partial Yes Yes Yes Amphipods present in NWT lakes near EKATI, therefore this is an acceptable surrogate (Amphipod) Holdich (1986) (Rescan 2011). The reported 95% confidence limits of LC50 (2,516 to 2,773 mg/L) suggest good control survival, despite control data not being reported. A 48hr-LC50 was also reported (3,618 mg/L; 95% CL of 3,481 to 3,758 mg/L). Used sodium molybdate. Secondary study as nominal concentrations used.

Invertebrates Ceriodaphnia dubia Mortality 48-hr LC50 1,015.0 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes C. dubia at EKATI. Value is the geometric mean of two LC50 replicates (1,005.5 and (planktonic crustacean) (Spiny waterflea) 1,024.6 mg/L). Hardness 86 mg/L. Primary study.

Invertebrates Daphnia magna Mortality 48-hr LC50 1,727.8 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Daphnids are found at EKATI. Value is the geometric mean of two LC50 replicates (planktonic crustacean) (Waterflea) (1,680.4 and 1,776.6 mg/L). Hardness 86 mg/L. Primary study.

Invertebrates Gammarus fasciatus Mortality 48-hr LC50 3,940.0 3,940.0 sodium molybdate Bionomics 1973; Yes Yes No Yes Yes Yes Yes Yes Scuds are found in lakes of NWT near EKATI (Rescan 2011). Secondary study as nominal (planktonic crustacean) (Amphipod) cited in NDEP concentrations used. 2008

FISH Fish (non-salmonid) Catostomus latipinnis Mortality 96-hr LC50 1,940.0 1,940.0 sodium molybdate Hamilton and Yes Yes No Yes Yes Yes Yes Yes Flannelmouth suckers are a good surrogate for white suckers which are resident at (Flannelmouth sucker) Buhl 1997 EKATI. Good test reporting, dose response (LC50 95%CL of 1680 to 2340 mg/L), indicating good endpoint fit and low control survival. Secondary study as nominal concentrations used.

Fish (non-salmonid) Pimephales promelas (Fathead Mortality 96-hr LC50 644.2 644.2 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Fathead minnows are a good surrogate for lake chub, and are widely used in toxicity minnow) tests in Canada. Value is the geometric mean of two LC50 replicates (609.1 and 681.4 mg/L). Hardness 85 mg/L. Primary study.

Fish (salmonid) Oncorhynchus mykiss Mortality 96-hr LC50 5,797.5 sodium molybdate Bionomics 1973; Yes Yes No Yes Yes Yes Yes Yes Rainbow trout are a good surrogate for round whitefish, which are present at EKATI. (Rainbow trout) cited in NDEP TL50s of 7340, 6790, and 4950 mg/L were reported for water hardnesses of 148, 154 2008 and 290 mg/L as CaCO3. Geometric mean used. Secondary study as nominal concentrations used.

Fish (salmonid) Oncorhynchus mykiss Mortality 96-hr LC50 (20 mm long 800.0 sodium molybdate McConnell 1977 Yes Yes No Yes Yes No Yes Yes Rainbow trout are a good surrogate for round whitefish, which are present at EKATI. (Rainbow trout)- 25mm fish) Secondary study as nominal concentrations used. Fish (salmonid) Oncorhynchus mykiss Mortality 96-hr LC50 (55 mm long 1,320.0 1,829.4 sodium molybdate McConnell 1977 Yes Yes No Yes Yes No Yes Yes Rainbow trout are a good surrogate for round whitefish, which are present at EKATI. (Rainbow trout)- 55mm fish) Secondary study as nominal concentrations used. Shaded values are from the same species and are used to calculate each species geometric mean. LC50 is the concentration at which 50% mortality of test organisms is expected NOEC is the No Observable Effect Level (Highest treatment concentration with no significant difference from controls). LOEC is the Lowest Observable Effect Level (Lowest concentration with an effect significantly different from controls). MATC is the Maximum Allowable Toxicant Concentration (concentration at threshold for effects; sometimes calculated as the geometric mean of the NOEC and LOEC).

Page 1 of 3 Appendix B. Acute Toxicity Studies on Molybdenum Available From the Literature

Species Geometric Mean Group Species (common name) Endpoint Effect Level Value (mg/L) (mg/L) Molybdenum species Reference Rationale for Acceptability Standardized Method Standardized AppropriateReplication Design and Measured Concentrations ofSensitive Use Lifestages ControlPerformance Factors Abiotic Report Dose- Acceptable response Procedures Statistical SUPPORTING ACUTE INFORMATION (Not used in the SSD, but used to support Primary Studies) INVERTEBRATES Invertebrates Daphnia magna Mortality 48-hr LC50 2,847.5 2,847.5 sodium molybdate Diamantino et Yes Yes No Yes No Yes Yes Yes Daphnids are present at EKATI. No control surival reported, and nominal values were (planktonic crustacean) (Waterflea) al. 2000 used, but the 95% confidence interval for LC50 was very narrow (2,838.7 to 2,857 mg/L), suggesting low control mortality. Supporting information, not used in the acute SSD.

FISH Fish (non-salmonid) Esox lucius Mortality 96-hr LOEC >127.7 >127.7 sodium molybdate Pyle 2000 Yes Yes Yes Yes No Yes No Yes N Pike are present in NWT. No dose response because the LOEC > highest treatment. (Northern pike) Supporting information only. Not used in SSD.

Fish (non-salmonid) Pimephales promelas (Fathead Mortality 96-hr LC50, LOEC >100 >100 sodium molybdate Pyle 2000 Yes Yes Yes Yes No Yes No Yes Fathead minnow are a surrogate for lake chub at EKATI. No dose response because the minnow) LOEC > highest treatment. Supporting information only. Not used in SSD.

Fish (non-salmonid) Pimephales promelas Mortality 96-hr LC50 628 628 molybdenum oxide Kimball 1978 Yes Yes Yes Yes No Yes No No Value based on geometric mean of two tests (LC50 of 577 and 678 mg/L). However, no (Fathead minnow) control or dose response data therefore can not use. Fatheads are a surrogate for lake chub at EKATI. Supporting information only. Not used in SSD.

Fish (non-salmonid) Catostomus commersoni Mortality 96-hr LC50, LOEC >2,000 >2,000 sodium molybdate Pyle 2000 Yes Yes Yes Yes No Yes No Yes White sucker are a surrogate for longnose suckers at EKATI. No dose response because (Whitesucker) the LOEC > highest treatment. Supporting information only. Not used in SSD.

Fish (salmonid) Oncorhynchus nerka (Kokanee Mortality 96-hr LC50, LOEC >2,000 >2,000 sodium molybdate Reid 2002 Yes Yes No Yes Yes Yes No Yes Pacific salmon and kokanee are surrogates for lake trout at EKATI. The LOEC>highest salmon) dose. However, it shows that the NOEC is at least at 2000 mg/L. Supporting information only. Not used in SSD.

Fish (salmonid) Oncorhynchus kisutch Mortality 96-hr LC50, LOEC >1,000 >1,000 sodium molybdate Hamilton and Yes Yes No Yes No Yes No Yes No dose-response defined. Salmon are a surrogate for lake trout at EKATI. Supporting (Coho salmon) Buhl 1990 information only. Not used in SSD.

Fish (salmonid) Oncorhynchus tshawytscha Mortality 96-hr LC50, LOEC >1,000 >1,000 sodium molybdate Hamilton and Yes Yes No Yes No Yes No Yes No dose-response defined. Salmon are a surrogate for lake trout at EKATI. Supporting (Chinook salmon) Buhl 1990 information only. Not used in SSD.

Fish (salmonid) Oncorhynchus mykiss Mortality 96-hr LC50 >1,000 >1,000 sodium molybdate Pyle 2000 Yes Yes Yes Yes No Yes No Yes Rainbow trout are a surrogate for round whitefish at EKATI. No dose response because (Rainbow trout) - alevin the LOEC > highest treatment. Supporting information only. Not used in SSD. Fish (salmonid) Oncorhynchus mykiss Mortality 96-hr LC50 >1,190 >1,190 sodium molybdate Pyle 2000 Yes Yes Yes Yes No Yes No Yes Rainbow trout are a surrogate for round whitefish at EKATI. No dose response because (Rainbow trout) -juvenile the LOEC > highest treatment. Supporting information only. Not used in SSD.

ACUTE STUDIES EXCLUDED FROM DATA SET AND REPORT INVERTEBRATES Invertebrates Daphnia magna (Waterflea) Mortality 48-hr LC50 3,220 3,220 sodium molybdate Bionomics 1973; No Unknown Unknown Yes Yes Unknown Unknown Yes Test did not report measured concentrations, dose response, abiotic factor values, or (planktonic crustacean) cited in NDEP other study design details therefore it could not be used. 2008 Invertebrates Daphnia magna (Waterflea) Mortality 48-hr LC50 206.7 206.7 molybdenum oxide Kimball 1978 Yes Yes Yes Yes No Yes No Yes Value based on geometric mean of two tests (LC50 of 203.2 and 210.3 mg/L). However, (planktonic crustacean) no control or dose response data therefore can not use. Also, the study used molybdenum oxide which has a different toxicity than molybdate. Invertebrates (benthic Hyalella azteca Mortality 7-day LC50, LOEC >1.0 >1.0 sodium molybdate Borgmann et al. No No No Yes Yes Yes No Yes No dose response (LOEC> highest treatment concentration), very low treatment range, crustacean) (Amphipod) 2005 and unusual test methods (feeding, no renewal of test water, extended duration for acute test), therefore not used.

Invertebrates (benthic Asellus aquaticus (Isopod) Mortality 7-day LC50, LOEC >1.0 >1.0 sodium molybdate Martin and Yes Yes No Yes No Yes Yes Yes Not a suitable species as no isopods are found at EKATI. Not used in report. crustacean) Holdich (1986)

Invertebrates (benthic) Chironomus plumosus Mortality 96-hr LC50 0.46 0.46 sodium molybdate Fargasova 1998; Yes Yes Unknown Yes Unknown Unknown Unknown Yes Results from this study using midge and tubificids are much lower than all other (Midge) cited in RIVM studies. No control or dose-response info available. Not used by RIVM, or in this study. 2005

Invertebrates (benthic) Tubifex tubifex Mortality 96-hr EC50 4.6 4.6 sodium molybdate Fargasova 1998; Yes Yes Unknown Yes Unknown Unknown Unknown Yes Results from this study using midge and tubificids are much lower than all other (Oligochaete) cited in RIVM studies. No control or dose-response info available. Not used by RIVM, or in this study. 2005 Shaded values are from the same species and are used to calculate each species geometric mean. LC50 is the concentration at which 50% mortality of test organisms is expected NOEC is the No Observable Effect Level (Highest treatment concentration with no significant difference from controls). LOEC is the Lowest Observable Effect Level (Lowest concentration with an effect significantly different from controls). MATC is the Maximum Allowable Toxicant Concentration (concentration at threshold for effects; sometimes calculated as the geometric mean of the NOEC and LOEC).

Page 2 of 3 Appendix B. Acute Toxicity Studies on Molybdenum Available From the Literature

Species Geometric Mean Group Species (common name) Endpoint Effect Level Value (mg/L) (mg/L) Molybdenum species Reference Rationale for Acceptability Standardized Method Standardized AppropriateReplication Design and Measured Concentrations ofSensitive Use Lifestages ControlPerformance Factors Abiotic Report Dose- Acceptable response Procedures Statistical UNACCEPTABLE ACUTE STUDIES EXCLUDED FROM DATA SET AND REPORT FISH Fish (non-salmonid) Punctius ticto Mortality 96-hr LC50 550 550 ammonium dimolybdate Pundir and Yes Unknown Unknown Yes Unknown Yes Unknown Yes No acceptable as this is a subtropical (Asian) group of fish; not a surrogate for any (Ticto barb) Saxena, 1990, EKATI fish. Not used. as reported in RIVM 2005

Fish (non-salmonid) Nemacheilus botia Mortality 96-hr LC50 211 211 ammonium dimolybdate Pundir 1989, as Yes Unknown Unknown Yes Unknown Yes Unknown Yes No acceptable as this is a Eurasian fish not found in northern Canada, and does not (Striped Loach) reported in relate to fish families at EKATI. Not used. RIVM 2005

Fish (non-salmonid) Lepomis macrochirus Mortality 96-hr LC50 6,790 6,790 sodium molybdate Bionomics 1973; Yes Unknown Unknown Yes Yes Unknown Unknown Yes Bluegills are not a good surrogate for non-salmonid fish at EKATI. LOEC> highest (Bluegill) cited in NDEP treatment, therefore no dose response. Not used in this report. 2008 Fish (non-salmonid) Lepomis macrochirus Mortality 96-hr LC50 1,320 1,320 sodium molybdate Easterday and Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Paper not available, study details could not be verified. Bluegills are not a suitable (Bluegill) Miller 1963; surrogate for the fish of EKATI. Not used for this report. cited in GEI 2009

Fish (non-salmonid) Pimephales promelas (Fathead Mortality 96-hr LC50 7,630 7,630 sodium molybdate Bionomics 1973; Yes Yes No Yes Yes Unknown Unknown Yes This value is more than 10 x higher than recent well documented studies, therefore not minnow) cited in NDEP acceptable (US EPA: Stephan et al 1985). Not used. 2008 Fish (non-salmonid) Pimephales promelas (Fathead Mortality 96-hr LC50 70 (for hardness of 70 (for hardness of unknown Tarzwell and Unknown No Yes Yes No Yes Yes Unknown There is not sufficient information to assess validity of this study (methods, controls,

minnow) 20 mg/L) 20 mg/L) Henderson dose-response). 96hr LC50 of 370 mg/L for hardness of 400 mg/L as CaCO3. Not used. 1960; cited in NDEP 2008.

Fish (non-salmonid) Ictalurus punctatus Mortality 96-hr LC50, LOEC >10,000 >10,000 sodium molybdate Bionomics 1973; Yes Unknown Unknown Yes Yes Unknown Unknown Yes Catfish are not a suitable surrogate for the fish of EKATI. Not used. (Channel catfish) cited in NDEP 2008

Fish (salmonid) Oncorhynchus mykiss Mortality 96-hr LC50 no effect of no effect of unknown Peterson (1974); Unknown Unknown Unknown Unknown Unknown Yes Unknown Unknown There is not sufficient information to assess validity of this study (methods, controls, (Rainbow trout) hardness on hardness on cited in dose-response, no measured concs). Not used. toxicity to rainbow toxicity to rainbow Hamilton and trout trout Buhl 1997

LC50 is the concentration at which 50% mortality of test organisms is expected NOEC is the No Observable Effect Level (Highest treatment concentration with no significant difference from controls). LOEC is the Lowest Observable Effect Level (Lowest concentration with an effect significantly different from controls). MATC is the Maximum Allowable Toxicant Concentration (concentration at threshold for effects; sometimes calculated as the geometric mean of the NOEC and LOEC).

Page 3 of 3 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Appendix C Chronic Toxicity Studies on Molybdenum Available From the Literature

Appendix C. Chronic Toxicity Studies of Molybdenum Available from the Literature

Species Species Geometric Group (common name) Endpoint Effect Level Chronic Value (mg/L) Mean (mg/L) Molybdenum species Reference Rationale for Acceptability StandardizedMethod Appropriate Replicationand Design Measured Concentrations Useof Sensitive Lifestages ControlPerformance ReportAbiotic Factors AcceptableDose- response StatisticalMethods Reported CHRONIC TESTS INCLUDED FROM THE DATA SET (Primary and Secondary Studies) PLANTS/ ALGAE Plant Lemna minor Growth 7-d EC10 241.5 241.5 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. Lemna sp. is a suitable (Duckweed) et al 2010 surrogate for aquatic macrophytes at EKATI, and is widely used in toxicity testing. Primary study.

Alga Chlorella regularis Growth 96-h EC50 50 50 ammonium dimolybdate Sakaguchi, 1981 Partial Yes No Yes Yes Partial Yes No Green algae are present at EKATI. The study provides a good dose response and control data info, but does (Green algae) not report measured concentrations in solution (only inside algae). Also, the pH may have been 5 which is low and could affect speciation of molybdate to less bioavailable form in acidic water. Secondary study as nominal concentrations used.

Alga Pseudokirchneriella Growth 72-h IC25 25.1 25.1 sodium molybdate Rescan 2011 Yes Yes Yes Yes Yes Yes Yes Yes Green algae are present at EKATI. The study provides control and dose response, and statistics (The 95% subcapitata confidence limits for the IC25 were 0.44 to 30.9 mg/L). The IC50 was reported as 86.5 mg/L (95% (Green alga) confidence limits of 9.7 to 130.1 mg/L). Primary study.

INVERTEBRATES Invertebrates (pelagic) Brachionus calyciflorus Population Growth 48-h EC10 193.6 193.6 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. Rotifers are present at EKATI, (Rotifer) et al 2010 therefore B. calyciflorus is a suitable surrogate species. Primary study.

Invertebrates (benthic) Lymnaea stagnalis Growth (length) 28-d EC10 211.3 211.3 sodium molybdate De Schamphelaere Partial Yes Yes Yes Yes Yes Yes Yes Methods reported in absence of standardized test, control results, dose response, 95% CI of endpoint (Snail) et al 2010 reported. Lymnaea is a surrogate for gastropods (e.g. fingernail clams) that are present at EKATI. Primary study.

Invertebrates (benthic) Chironomus riparius Growth (biomass) 14-d EC10 121.4 121.4 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. Chironomids are present at (Midge) et al 2010 EKATI. Primary study.

Invertebrates (planktonic Ceriodaphnia dubia Reproduction 8-d IC12.5 34 sodium molybdate Naddy et al 1995 Yes Yes Yes Yes Yes Yes Yes Yes C. dubia is present at EKATI. An 8-d IC25 of 47 mg/L was also reported. Primary study. crustacean) (Spiny waterflea) Invertebrates (planktonic Ceriodaphnia dubia Reproduction 7-d EC10 78.2 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. C. dubia is present at EKATI. crustacean) (Spiny waterflea) et al 2010 Primary study. Invertebrates (planktonic Ceriodaphnia dubia Reproduction 6-d EC10 50.8 51.3 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. C. dubia is present at EKATI. crustacean) (Spiny waterflea) Primary study.

Invertebrates (planktonic Daphnia magna Reproduction 21-d MATC 61.2 sodium molybdate Diamantino et al. Yes Yes No Yes Yes Yes Yes Yes Daphnids are present at EKATI, therefore D. magna is a good surrogate. The NOEC (50 mg/L) and LOEC (75 crustacean) (Waterflea) 2000 mg/L) were used to calculate geometric mean MATC (both growth and reproduction). Also reported were MATC of 61.2 mg/L (growth) and 86.6 mg/L (survival). Secondary study as nominal concentrations used.

Invertebrates (planktonic Daphnia magna Reproduction 21-d EC10 105.6 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. Daphnids are present at EKATI. crustacean) (Waterflea) et al 2010 Primary study. Invertebrates (planktonic Daphnia magna Reproduction 21-d EC10 107.9 88.7 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response reported. Value is geometric mean of 2 replicates (106 and crustacean) (Waterflea) 110 mg/L). Daphnids are present at EKATI. Primary study.

FISH Fish (non-salmonid) Pimephales promelas Growth (Dry 34-d EC10 39.3 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. Fathead minnows are a (Fathead minnow) Weight) et al 2010 surrogate for lake chub at EKATI. Primary study. Fish (non-salmonid) Pimephales promelas Growth (Dry 28-d EC10 90.9 59.8 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. Fathead minnows are a (Fathead minnow) Weight) surrogate for lake chub at EKATI. EC10 based on geometric mean of two replicate tests (83.2 and 99.2 mg/L). Primary study.

Fish (salmonid) Oncorhynchus mykiss Growth (biomass) 7-d EC10 43.2 43.2 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Good methods, control results, dose response, 95% CI of endpoint reported. Rainbow trout are a surrogate (Rainbow trout) et al 2010 for round whitefish at EKATI. EC10 reported is the geometric mean of two replicate test EC10s (36.9 and 43.2 mg/L). Primary study. Shaded values are from the same species and are used to calculate each species geometric mean.

ICx (e.g. IC 20 ) is the concentration at which x % of test organisms are expected to be inhibited (e.g. inhibited reproduction).

ECx (e.g. EC 10 ) is the concentration at which x % of test organisms are expected to show an effect.

LCx (e.g. LC 50 ) is the concentration at which x% mortality of test organisms is expected NOEC is the No Observable Effect Level (Highest treatment concentration with no significant difference from controls). LOEC is the Lowest Observable Effect Level (Lowest concentration with an effect significantly different from controls). MATC is the Maximum Allowable Toxicant Concentration (concentration at threshold for effects; sometimes calculated as the geometric mean of the NOEC and LOEC).

Page 1 of 3 Appendix C. Chronic Toxicity Studies of Molybdenum Available from the Literature

Species Species Geometric Group (common name) Endpoint Effect Level Chronic Value (mg/L) Mean (mg/L) Molybdenum species Reference Rationale for Acceptability StandardizedMethod Appropriate Replicationand Design Measured Concentrations Useof Sensitive Lifestages ControlPerformance ReportAbiotic Factors AcceptableDose- response StatisticalMethods Reported SUPPORTING CHRONIC TOXICITY INFORMATION (Not used in SSD, but used to support primary studies) PLANTS/ ALGAE Alga Scenedesmus sp. Growth 96-h tox threshold 54 54 ammonium dimolybdate Bringmann and Unknown Unknown No Yes Yes Unknown No No The paper did not provide enough detail to verify results, dose response, control survival (just lists effect (Green alga) (chronic) Kuhn, 1959 threshold of 54 mg/L). Supporting information only; not used in SSD.

Alga Scenedesmus Growth (number of 12-d EC50 3.71 3.71 ammonium dimolybdate Fargasova et al 1999 No Yes No Yes No No Partial Yes Scenedesmus is appropriate as green algae are present at EKATI. However, no measured concentrations, no quadricauda cells) clear reporting of dose response, controls, uncertainty in units; static test no renewal. Supporting (Green alga) information only. Not used in SSD.

Alga Scenedesmus Growth 72-h NOEC 12.5 12.5 sodium molybdate Huntington Research Unknown Unknown No Unknown Unknown Unknown Unknown Unknown Paper not found, could not verify; rated as unreliable K3 by De Schampheleare et al 2010. Supporting subspicatus Council 1994; cited information only; not used in SSD. (Green alga) in De Schampelaere et al 2010

Alga Pseudokirchneriella Growth 72-h NOEC 4.6 4.6 sodium molybdate Huntington Research Unknown Unknown No Unknown Unknown Unknown Unknown Unknown Paper not found, could not verify; rated as unreliable K3 by De Schampheleare et al 2010. Supporting subcapitata Council 1994; cited information only; not used in SSD. (Green algae) in De Schampelaere et al 2010

INVERTEBRATES Invertebrates (planktonic Daphnia magna Survival 21-d EC10 200 200 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Using more sensitive endpoint (reproduction). Good methods, control results, dose response, reported. crustacean) (Waterflea) Value is the geometric mean of two replicates (145 and 275 mg/L). Supporting information only; not used in SSD. Invertebrates (planktonic Daphnia magna Survival 21-d EC50 102.1 102.1 sodium molybdate Diamantino et al. Yes Yes No Yes Yes Yes Yes Yes Valid study on mortality; but already using the more sensitive endpoint (reproduction). Supporting crustacean) (Waterflea) 2000 information only; not used in SSD.

Invertebrates (planktonic Ceriodaphnia dubia Survival 6-d EC10 187.9 187.9 sodium molybdate GEI 2009 Yes Yes Yes Yes Yes Yes Yes Yes Using more sensitive endpoint (reproduction). Good methods, control results, dose response, 95% CI of crustacean) (Spiny waterflea) endpoint reported. Supporting information only; not used in SSD. Invertebrates (planktonic Ceriodaphnia dubia Survival 7-d MATC* 231.2 231.2 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Using more sensitive endpoint (reproduction). Good methods, control results, dose response, 95% CI of crustacean) (Spiny waterflea) et al 2010 endpoint reported. MATC calculated as the geometric mean of the NOEC (177 mg/L) and the LOEC (302 mg/L). Supporting information only; not used in SSD.

FISH Fish (salmonid) Oncorhynchus mykiss Survival 32-d MATC 866 866 sodium molybdate Davies et al 2005 Yes Yes Yes Yes Yes Yes Yes Yes MATC based on geometric mean of NOEC (750 mg/L) and LOEC (1000 mg/L); LC20 of 1425 mg/L also (Rainbow trout) reported. Rainbow trout are a surrogate for round whitefish at EKATI. Supporting information only; not used in SSD.

Fish Pimephales promelas Growth 7-d NOEC 100 100 sodium molybdate Pyle 2000 Yes Yes No Yes Yes Yes No No LOEC>highest treatment, therefore no dose response. Supporting information only; not used in SSD. (Fathead minnow) Fish Pimephales promelas Time to hatch, Egg 3-d NOEC 100 100 sodium molybdate Pyle 2000 Yes Yes No Yes Yes Yes No No LOEC>highest treatment, therefore no dose response. Supporting information only; not used in SSD. (Fathead minnow) survival

ICx (e.g. IC 20 ) is the concentration at which x % of test organisms are expected to be inhibited (e.g. inhibited reproduction).

ECx (e.g. EC 10 ) is the concentration at which x % of test organisms are expected to show an effect.

Page 2 of 3 Appendix C. Chronic Toxicity Studies of Molybdenum Available from the Literature

Species Species Geometric Group (common name) Endpoint Effect Level Chronic Value (mg/L) Mean (mg/L) Molybdenum species Reference Rationale for Acceptability StandardizedMethod Appropriate Replicationand Design Measured Concentrations Useof Sensitive Lifestages ControlPerformance ReportAbiotic Factors AcceptableDose- response StatisticalMethods Reported UNACCEPTABLE CHRONIC TESTS EXCLUDED FROM THE DATA SET and REPORT PLANTS/ ALGAE Alga Scenedesmus sp. Growth 96-h tox threshold 54 54 sodium molybdate McKee and Wolf, Unknown Unknown No Yes Yes Unknown No No Based on Bringmann and Kuhn 1959 (listed above already), not a new study. (Green alga) (chronic) 1963 ( based on Bringmann and Kuhn 1959)

INVERTEBRATES Invertebrates (planktonic Daphnia magna Reproduction 28-d MATC 0.878 0.878 molybdenum oxide Kimball 1978 Yes Yes Yes Yes Yes Yes Yes Yes MATC calculated as the geometric mean of NOEC (0.67 mg/L) and LOEC (1.15 mg/L). Daphnia are present at crustacean) (Waterflea) EKATI. Test used molybdenum oxide, and is 70 to 123 times lower than other studies, therefore is not used based on US EPA guidance (Stephan et al. 1985). Invertebrates (planktonic Daphnia magna Survival 28-d LC50 0.93 0.93 molybdenum oxide Kimball 1978 Yes Yes Yes Yes Yes Yes Yes Yes Test results are 100 lower than other studies which are more recent and more well documented. Not used. crustacean) (Waterflea)

AMPHIBIANS Amphibian Xenopus laevis Malformation 4-d EC10 115.9 115.9 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Not a good surrogate as there are no amphibians at EKATI. (African clawed frog) et al 2010 Amphibian Xenopus laevis Survival 4-d EC10 415.4 415.4 sodium molybdate De Schamphelaere Yes Yes Yes Yes Yes Yes Yes Yes Not a good surrogate as there are no amphibians at EKATI. (African clawed frog) et al 2010

Amphibian Gastrophryne Survival 7-d LC50 0.96 0.96 not reported Birge et al. 1978 No Unknown No Yes No Yes Yes Unknown Not a good surrogate as there are no amphibians at EKATI, and not a standardized test, no control survival carolinensis reported. (Narrow-mouthed toad)

FISH Fish (non-salmonid) Carassius auratus Survival 7-d LC50 60 60 not reported Birge 1978 No No Yes Yes No Yes Unknown Unknown No, poor test reporting, and not a good surrogate species for fish at EKATI. (Goldfish)

Fish (non-salmonid) Esox lucius Growth (Weight) 13-d IC25, LOEC >1.7 >1.7 sodium molybdate Pyle 2000 No Yes No Yes Yes Yes No Yes LOEC>highest treatment, therefore no dose response. Very low treatment range. (Northern pike)

Fish (non-salmonid) Catostomus commersoni Survival 22-d EC50, LOEC >1.7 >1.7 sodium molybdate Pyle 2000 Yes Yes No Yes Yes Yes No No LOEC>highest treatment, therefore no dose response. Very low treatment range. (White sucker)

Fish (salmonid) Oncorhynchus mykiss Survival 1-yr LOEC >17 >17 sodium molybdate McConnell 1977 Yes Yes No Yes Yes Yes No No LOEC>highest treatment, therefore no dose response. Very low treatment range. (Rainbow trout) Fish (salmonid) Oncorhynchus mykiss Survival 18-mo EC20 >18.5 >18.5 sodium molybdate Goettl et al. 1976 Yes Yes Unknown Yes Unknown Yes No No LOEC>highest treatment, therefore no dose response, very low treatment range, and no control surival (Rainbow trout) data. Fish (salmonid) Oncorhynchus mykiss Survival 7-d LC50 0.96 0.96 not reported Birge 1978 No Yes No Yes No Yes Yes Yes Non standard methods used, and results not clearly reported; results do not match the well documented (Rainbow trout) repeat study of Davies et al 2005. Not used. Fish (salmonid) Oncorhynchus mykiss Survival 28-d LC50 0.73 0.73 not reported Birge 1978 No Yes No Yes No Yes Yes Yes Non standard methods used, and results not clearly reported; results do not match the well documented (Rainbow trout) repeat study of Davies et al 2005. Not used. Fish (salmonid) Oncorhynchus mykiss Survival 28-d LC50 0.79 0.79 not reported Birge et al 1980 No Yes No Yes Yes Yes Yes Yes Non standard methods used, and results not clearly reported; results do not match the well documented (Rainbow trout) repeat study of Davies et al 2005. Not used. Fish (salmonid) Oncorhynchus mykiss Survival 28-d NOEC, LOEC 200, 400 200, 400 sodium molybdate Davies et al 2005 No Yes Yes Yes Yes Yes Yes Yes This test replicated Birge's test using Birge's non-standard methods. This report uses Davies et al 2005 data (Rainbow trout) using standardardized methods listed above. Not used.

ICx (e.g. IC 20 ) is the concentration at which x % of test organisms are expected to be inhibited (e.g. inhibited reproduction).

ECx (e.g. EC 10 ) is the concentration at which x % of test organisms are expected to show an effect.

Page 3 of 3 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Appendix D Chronic Algal Bioassay on Molybdenum Conducted in December 2010

Toxicity Testing of Molybdenum with the Freshwater Alga Pseudokirchneriella subcapitata

Final Toxicity Test Report

Report date: January 20, 2011

Submitted to:

RESCAN ENVIRONMENTAL SERVICES LTD. Vancouver, BC

8664 Commerce Court Burnaby, BC V5A 4N7

GLOSSARY OF TERMS USED IN THIS REPORT

IC25, IC50 The inhibition concentration is the concentration of sample that is estimated to cause a 25 or 50% growth reduction relative to the control.

Confidence Intervals These intervals represent the upper and lower concentrations within which the point estimate (e.g., LC50, IC25) is found. Thus, the 95% confidence intervals indicate that there is a 19 out of 20 (95%) chance that the endpoint is within the specified intervals.

Cell Yield The concentration of algal cells at the end of the 72-h exposure period relative to the initial cell density.

CV Coefficient of Variation, which is the standard deviation divided by the mean and expressed as a percentage.

INTRODUCTION

Molybdenum was evaluated for toxicity by Nautilus Environmental, as requested by Rescan Environmental Services. The chemical was tested with the freshwater alga Pseudokirchneriella subcapitata (formerly Selenastrum capricornutum). This report describes the results of the toxicity test. Copies of raw laboratory datasheets are provided in Appendix A. The results presented herein relate only to the chemical tested.

METHODS

Methods for the Pseudokirchneriella subcapitata toxicity test are summarized in Table 1. Statistical analyses for all the test data were performed using CETIS (Tidepool Scientific Software, 2009) on the basis of measured concentrations of Mo.

The nominal Mo test concentrations were prepared using sodium molybdate crystals

(Na2MoO4.2H2O, CAS 10102-40-6). The highest concentration of Mo that was tested was prepared by adding the appropriate amount of sodium molybdate crystals into control water. The remaining lower concentrations were then prepared by serial dilution, following a 0.5 X dilution series. Control and dilution water was distilled water, supplemented with nutrients required by this species. Subsamples of the test solutions were collected and analyzed for total Mo concentrations. Analyses were conducted by ALS Laboratory Group, Burnaby, BC.

RESULTS

Results of the toxicity test are shown in Table 2. Nonlinear regression models failed to meet the statistical fit for the type of data generated and, therefore, the point estimates for this test were analyzed using log-linear interpolation. The IC25 and IC50 (95% confidence limits) values for were 25.1 (0.44 – 30.9) and 86.5 (9.7 – 130.1) mg/L Mo, respectively.

QA/QC

The test met the acceptability criteria for validity as specified in the Environment Canada protocol. Water quality parameters measured during the toxicity test were within acceptable ranges.

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Results of the reference toxicant test conducted during the testing program were within the laboratory historical mean  two standard deviations. This indicates that the algae evaluated in the reference toxicant test were within acceptable levels of quality and sensitivity. The reference toxicant test results for this species are summarized in Table 3.

Table 1. Summary of test conditions for the Pseudokirchneriella subcapitata growth inhibition test.

Test organism Pseudokirchneriella subcapitata, strain UTCC #37 In-house culture, originally obtained from Test organism source Canadian Phycological Culture Center, University of Waterloo, isolated from Nitelva River, Norway Test organism age 3 to 7-day old culture in logarithmic growth phase Test type Static Test duration 72 hours Test chamber Microplate Test solution volume 220 µL Test concentrations (% sample) Seven concentrations, plus laboratory control Number of replicates 4 for treatments; 8 for control Control/Dilution water Deionized or distilled water Test solution renewal None Test temperature 24 ± 2°C Number of organisms/chamber 10,000 cells/mL Light intensity 3600 to 4400 lux Photoperiod Continuous light Aeration None Test protocol Environment Canada (2007), EPS 1/RM/25 Test endpoint Algal cell growth inhibition  16-fold increase in number of algal cells; control must not exhibit a positive or negative trend with Test acceptability criteria for controls Mann-Kendall test; and the coefficient of variation of the control replicates must not exceed 20%. Reference toxicant Zinc

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Table 2. Toxicity test results for the Pseudokirchneriella subcapitata growth inhibition test.

Cell Yield (x 104 cells/mL) Test Concentration (mg/L Mo) (mean  SD)

Control 58.9  6.0 10.3 46.8  10.8 20.3 53.8  11.0 40.6 29.0  1.8 80 31.5  4.4 159 21.8  7.1 321 24.5  5.7 610 14.2  5.6 Test endpoint (mg/L Mo) IC25 (95% CL) 25.1 (0.44 – 30.9) IC50 (95% CL) 86.5 (9.7 – 130.1) IC = Inhibition Concentration. SD = Standard Deviation. CL = Confidence Limits.

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Table 3. Reference toxicant test results.

Mean and CV Species Test date IC50 Historical Range (%) 23.6 Pseudokirchneriella December 20, 2010 Algal Growth: 28.6 μg/L Zn 11.9– 47.0 μg/L 41% subcapitata Zn

REFERENCES

Environment Canada. 2007. Biological test method: growth inhibition test using the freshwater alga. Environmental Protection Series, Report EPS 1/RM/25. Second Edition, March 2007. Environment Canada, Method Development and Application Section, Environmental Science and Technology Centre, Science and Technology Branch, Ottawa, ON. 53 pp.

Tidepool Scientific Software. 2009. CETIS comprehensive environmental toxicity information system, version 1.7.0. Tidepool Scientific Software, McKinleyville, CA. 222 pp.

Nautilus Environmental 5

APPENDIX A – Toxicity Test Data

Pseudokirchneriella subcapitata Summary Sheet

Client: Rescan Start Date: December 20.2010 Work Order No.: 10506 Set UP bv: ECC

Sample Information:

Sample ID: Molybdenum Sample Date: NA Date Received: NA Saniple Volunie: NA

Test Organism Information:

Culture Date: December 17.2010 Age of culture (Day 0):

Zinc Reference Toxicant Results:

Reference Toxicant ID: - -- - - Stock Solution ID: 10Zn01 Date Initiated: December 20,2010

72-h IC50 Reference Toxicant Mean and Range: 23.6, 11.9 - 47.0 CV (%): 41%. 'MIL * Test ResuIts: Algal Growth IC25 %(v/v) (95% CL) 25.1 (0.44 - 30.9) WIL lC50 %(v/v) (95% CL) 86.5 (9.7 - 130.1) )aprlc

Reviewed by: Date reviewed: 76~* /UP/

Modified May 8, 2008; Ver. 1.0 Nautilus Environmental 72-h Algal Growth Inhibition Toxicity Test Water Quality Measurements

Client : Rescan Setup by: ECC

Sample ID: Test DatelTime: December ?0,2OlO ( L~QL

Work Order No.: Test Species: Pseudokirchneriella subcapitata

Culture Date: p-13 %I3 Age of Culture: 362 Culture Health: Gf-9

Culture Count: I 2 Tq Average: q? Culture Cell Density (cl): Ci'? Y iOq

220,000 cellslml x fkornl vl = = \\- 34 * cellslml (C1) qyroq &- Time Zero Counts: 1 23 2q Average: 73 Y Lo ' ~o.of~ellslrn~: 'LS:$XL~~Initial Density: # cells1mL + 220 pL x 10 pL = 106e~-

Water Quality Measurements Concentration Microplates rotated 2X per day? C- i~h)pH Temp (Oc) (3 h Oh 24h 48h 72h 0 h 24 h 48 h 72 h Control 6-7 -~$Lz&Q 26.0 J/ JJ J \ex &*C( z2-c*D 26-07L6.~ JJ dJ 2;s 0.7 z~3~3~po&.o~.o J Js/ /1/ J J c*o 6.4 23-<24.0 *a " d 1/,/ LO drci zaC26.0 zb-@%Q JJ JJ JJ / =m 6-4 2%~~'0 %-Q 3k.o /J JJJJ J' 46 6-4 3.3~76-0 &a JdJJJJ b8 L-7 23c~~ J /J /L/ JJ

Initial control p~:Well I: 6' well 2: 6-g Final control pH: Well 1: 0.: Well 2: b ts Light intensity (lux): 3 71 0 Date measured:

Sample Description:

Comments:

Reviewed: 3% Date reviewed: la#* 14/11 u I

Version 1.0 Modified May 8,2008 Nautilus Environmental 72-h Algal Growth Inhibition Toxicity Test Water Quality Measurements

Client : Rescan Setup by: ECC

Sample ID: 'wm ( ~~b)Test DatelTime: December 20,201 0 1 b %h

Work Order No.: 16P Test Species: Pseudokirchneriella subcapitata

Culture Date: b I*rw ~~e of Culture: 3 8- Culture Health: &A Culture Count: 1 qb 2 qg Average: q? Culture Cell Density (cl): 47q~b4

Time Zero Counts: Average: 2.3 XYLO'

NO. of ~ellslrn~: 'I?*< 'Q Initial Density: # cellslmL + 220 pL x 10 pL = 1ob dz

Water Quality Measurements Concentration Microplates rotated 2X per day? PH Temp (OC) [n-.d-~~h) Oh Oh 24h 48h 72h 0 h 24 h 48 h 72 h MO 6-a z3.~2~.o%e~~r0JJ JJ /J

initial control p~:we11 I: 6 - g Well 2: 6 .,tS

6 a&- Final control pH: Well 1: Well 2: 6 -A/

Light intensity (lux): 3?/ 0 Date measured:

Sample Description:

Comments:

Reviewed: Date reviewed: 7.W I+/,( I

Version 1.0 Modified May 8, 2008 Nautilus Environmental Pseudokirchneriella subcapitata Toxicity Test Data Sheet 72-h Algal Cell Counts

Client: Rescan Start DateITime: 20-Dec-10 I6 ?o k Work Order #: Termination Date: 23-Dec-I 0

D 43' A $3 B 60 10.0 C \ 3 D z8 kll T A cq fa B 40

m*a , c J+ D bf Gs I A 'z$ 43 -b B 31 c --zF;' D 3> A 80 'a B 2% 31 C A0 . D 'tj

Comments:

Reviewed by: 36 Date Reviewed:

Version 1.0 Modified May 8, 2008 Nautilus Environmental Pseudokirchneriella subcapitata Toxicity Test Data Sheet 72-h Algal Cell Counts

Client: Rescan Start DateITime: 20-Dec-10 tb 3a Work Order #: Termination Date:

B C D A B C D A -B C -1 D A B C D A B C D

Comments:

Reviewed by: Jm+- Date Reviewed: 76~P I+/// I

Version 1.0 Modified May 8, 2008 Nautilus Environmental Pseudokirchneriellasubcapitata Algal Counts

Client: Rescan Start DateITime: 20-Dec-10 @1630h WO#: 10506 Termination Date: 23-Dec-10 Sample ID: Molybdate Initial Cell Density: 10682 cell1mL

Concentration Count 1 Count 2 Count3 Count4 Mean Cell Yield % vlv (X I04) (X I04) (X I04) (X I04) (X I04) (X I04) cell1mL Control 57 55.9 mean 61 59.9 SD 66 64..9 CV 54 52.9 5 1 49.9 67 7 1 67.9 59 57.9 62 60.9 58 56.9 65 63.9 64 62.9 52 50.9 66 64.9 40 39 38.4 53 51.9 57 55.9 68 66.9 50 48.9 65 63.9 59 57.9 53 51.9 60 58.9 41 43 40.9 38 35 35.4 59 57.9 40 38.9 54 52.9 68 65 65.4 29 27.9 31 29.9 28 26.9 32 30.9 34 32.9 28 3 1 28.4 36 40 36.9 29 27.9 27 25.9 12 14 11.9 22 20.9 29 27.9 23 21.9 19 19 17.9 28 26.9 31 33 30.9 13 13 11.9 9 7.9 18 16 15.9 2 1 24 21.4 CETIS Analytical Report Report Date: 14 Jan-11 10:15 (p 1 of 2) Test Code: 00-9455-3490110506b - EC Alga Growth Inhibition Test Nautilus Environmental

Analysis ID: 04-8869-4322 Endpoint: Cell Yield CETlS Version: CETISv1.7.0 Analyzed: 14 Jan-1 1 10:15 Analysis: Linear Interpolation (ICPIN) Official Results: Yes

Batch ID: 01-0096-3239 Test Type: Cell Growth Analyst: Start Date: 20 Dec-10 Protocol: ECIEPS 1lRMl25 Diluent: Deionized Water Ending Date: 23 Dec-10 Species: Pseudokirchneriella subcapitata Brine: Duration: 72h Source: In-House Culture Age:

Sample ID: 18-9710-361 2 Code: Molybdenum Client: Rescan Sample Date: 20 Dec-10 Material: chemical Project: Receive Date: Source: Rescan Sample Age: NIA Station:

Linear lnterpolation Options X Transform Y Transform Seed Resamples Exp 95% CL Method Log(X+ 1) Linear 57951 200 Yes Two-Point Interpolation

Residual Analysis Attribute Method Test Stat Critical P-Value Decision(5%) Extreme Value Grubbs Extreme Value 2.3577 2.9906 0.5218 No Outliers Detected Control Trend Mann-Kendall Trend 4 0.71 95 Nonsignificant Trend in Controls

Point Estimates Level gm/L 95% LCL 95% UCL tw+a4@-

Cell Yield Summary Calculated Variate Conc-gmlL Control Type Count Mean Min Max Std Err Std Dev CV% DiWh 0 Negative Control 10.3 20.3 40.6 80 159 32 1 61 0

Cell Yield Detail Conc-gmlL Control Type Rep 1 Rep 2 Rep 3 Rep4 Rep 5 Rep 6 Rep 7 Rep 8 0 Negative Control 56 60 65 53 50 68 58 61

Analyst: QA: 36-4~ Ja* /lf/l( CE'TIS Analytical Report Report Date: 14 Jan-11 10:15(p2of 2) Test Code: 00-9455-349011 0506b EC Alga Growth Inhibition Test Nautilus Environmental

Analysis ID: 04-8869-4322 Endpoint: Cell Yield CE'I'IS Version: CE-I-ISv1.7.0 Analyzed: 14 Jan-1 1 10:15 Analysis: Linear Interpolation (ICPIN) Official Results: Yes

Graphics

Analyst: QA: J& WIb NAUTILUS ENVIRONMERITAL Date Received: 06-JAN - 1 1 ATTN: Edmund Canaria Report Date: 1 3-JAIV - 1 1 I7: I 3 (MT) Version: FINAL 8664 Corr~rr~erceCourt Imperial Square Lake City Burnabv BC V5A 4N7 Phone: 604-420-8773

Certificate of Analysis Lab Work Order #: L967948 Project P.O. #: PROJECT #O125; WO# 10506 Job Reference: Legal Site Desc: C of C Numbers:

Can Dang Account Manager [This report shall not be reproduced except in full without the written authority of the Laboratory.]

ADDRESS: 8081 Lougheed Hwy, Suite 100, Burnaby, BC V5A 1W9 Canada I Phone: +I 604 253 4188 1 Fax: +I 604 253 6700 ALS CANADA LIMITED Part of the ALS Group A Campbell Brothers Limited Company L967948 CONTD.... PAGE 2 of 4

ALS LABORATORY GROUP ANALYTICAL REPORT 13JAN-11 17:13(MT) Version: FINAL L967948 CONTD.... PAGE 3 of 4

ALS LABORATORY GROUP ANALYTICAL REPORT 13JAN-11 17:13(MT) Version: FINAL L967948 CONTD.... PAGE 4 of 4 13JAN-11 17:13 (MT) Reference Information Version: FINAL Test Method References: ALS Test Code Matrix Test Description Method Referencef*

M ET-TOT-ICP-VA Water Total Metals in Water by ICPOES EPA SW-846 3005A16010B This analysis is carried out using procedures adapted from "Standard Methods for the Examination of Water and Wastewater" published by the American Public Health Association, and with procedures adapted from "Test Methods for Evaluating Solid Waste" SW-846 published by the United States Environmental Protection Agency (EPA). The procedures may involve preliminary sample treatment by acid digestion, using either hotblock or microwave oven (EPA Method 3005A). Instrumental analysis is by inductively coupled plasma - optical emission spectrophotometry (EPA Method 6010B). -- - -- ** ALS test methods may incorporate modifications from specified reference methods to improve performance. The last two letters of the above test code(s) indicate the laboratory that performed analytical analysis for that test. Refer to the list below:

-- - - - .- Laboratory Definition Code Laboratory Location VA ALS LABORATORY GROUP - VANCOUVER, BC, CANADA

Chain of Custody Numbers: ------GLOSSARY OF REPORT TERMS Surrogate A compound that is similar in behaviour to target analyte(s), but that does not occur naturally in environmental samples. For applicable tests, surrogates are added to samples prior to analysis as a check on recovery. mg/kg milligrams per kilogram based on dry weight of sample. mgkg wwt milligrams per kilogram based on wet weight of sample. mgkg Iwt milligrams per kilogram based on lipid-adjusted weight of sample. mg/L milligrams per litre. < - Less than. D.L. The reported Detection Limit, also known as the Limit of Reporting (LOR). N/A Result not available. Refer to qualifier code and definition for explanation.

Test results reported relate only to the samples as received by the laboratory. UNLESS OTHERWISE STATED, ALL SAMPLES WERE RECEIVED IN ACCEPTABLE CONDITION. Analytical results in unsigned test reports with the DRAFT watermark are subject to change, pending final QC review. -- --

TESTING LOCATION (Please Circle) ~utilus6wirowteKtm[ Chain of Custody British Calumbia hway &st Suite 2 8664 Commerce Court Bumaby,Phone 604.420.8773 Brltish Coli~rnb~a, Canada V5A 4N3

*,-g679L. Fax 604 357.1361 ~96tVt9 \\l\l\\\\\\\\\\\~\u~[~~l~i~?-.J Sample CollectIan By: ANALYSES REQUIRED r A RepolZ to: Invoice To: E4 Company Nautilus Environmental Company g! Address a Address 8664 Commerce Court A 0 City/ State/Zi~ Burnaby BC, VSA4N3 Clty/State/Zlp E w i Contact Edrnund Canaria Contact 5 B C C Phone 604-420-8773 Phone x Emall edmund~nautllu6envrr~nmental.com Email g ,. Z 'E PL Co;nrAINER ! NO. OF 5 SAMPLE ID DATE TIME MATRIX COMMENTS : TYPE CONTAINERS F--. 10 mg/LMo 20-0ec-10 125 rn~bottle i Overlying water Day 0 n 125 ml bottle 1 20mgjL Mo 20-Dec- 10 Overlying water Day 0 K 40mg/LMo 125 ml bottle I 1 Overlying water Day 0 20- bec-10 W 1 80mg/l Mo 20-bec-I0 125 rnl bottle Overlying water Day 0 K 125 mi bottie I Overlying water bay O 5 160 mf/ L Mo 20-0ec-10 K 6 . 320mg/LM0 20-Dec-iO 125 ml bottle 1 Overlying water Day 0 Y .. . mg/L 125 mt battle 1 640 Mo 20-Dec-10 Overlying water Day 0 X 8

10 L PROJECT INFORMATION SAMPLE RECElPT RELINQUISHED BY (CLIENT) RELINQUISHED BY (COURIER) ISgnature) 1 #fi F fs~onature) Fme) Client: Total No. of Containers Ld)"'fj'h, "/" (Prlntd Name) Julbanna G ~aloczll 'printed ~amd X0125; WoIY u (D (Date) PO NO.: Pro'ect Received Good Condition? 10506 . - , b/ p-p- Shipped Matches Test Schedule? Via: i -- SPECIAL INSTRUmONS/COMMENTS: 72-h Algal Growth Inhib~tionTest; Sarnpes RECEIVED BY (COURIER) RECEIVED BY [LABORATORY) were not prserved, Please submit results by January 13/11. (Sqnature) {T~me) (Lanature)c- 6';- (Printed Name) [Date) (Pnnted Name)

(Compsnyl (Cm~any)

#LS 86y 4 L Additional costs may be required for sample disposal or storage. Payment net 30 unless otherwise contracted. EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Appendix E Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software

Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software

Model Normal Logistic Gompertz Weibull FisherTippett ∑ei2 0.0145 0.0138 0.0177 0.0161 0.0206 MSE 0.0016 0.0015 0.0020 0.0018 0.0023 Normal residuals? D'AgostinoPearson (n>20) Yes No Yes Yes Yes Normal residuals? ShapiroFrancia (n>7) Yes Yes Yes Yes Yes Data from specified distribution? AndersonDarling (n>5) Yes Yes Yes Yes No A2 (AndersonDarling) 0.676 0.351 0.416 0.440 4.786 HC5(mg/L) 363.07 324.33 222.74 276.86 469.53 Lower confidence limit on the mean (expected HC5) 268.61 156.82 109.90 127.04 215.90 Upper confidence limit on the mean (expected HC5) 490.76 670.78 451.45 603.34 1021.14

Model Parameter Estimates Location Model Shape notation Shape Estimate Scale Notation Scale Estimate Location Notation Estimate Normal σ 0.372410855 3.172555322 Logistic σ or s 0.224860363 3.17307508 Gompertz σ or s 0.323101418 3.307480708 Weibull κ 9.818737925 λ 3.304958792 FisherTippett b or s 0.328483853 or L 3.032074943

1.0

0.8

0.6

0.4 Proportion ofAffected Taxa Proportion Normal 0.2 Logistic Gompertz Weibull FisherTippett

0.0 1 10 100 1000 10000 100000 1000000 Molybdenum Concentration (mg/L) Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software 1.0 Model 3 Gompertz

Variables Parameter Estimates Statistics Values 0.8

2 3.307480708 ∑ei 0.01774879 σ 0.323101418 MSE 0.00197209 0.6

Residual Normality 0.4 Test Test Critical Value (α=0.05) Normal? PValue Statistic 0.2 2 3.646 2 5.991 Yes 0.1615 Gompertz Model D'AgostinoPearson, K (n≥20) χ (2df) Proportion ofTaxa Affected ShapiroFrancia, W' (7≤n) 0.944 z 1.645 Yes 0.1726 Confidence Limits 0.0 AndersonDarling GoodnessofFit (n≥5) 1 10 100 1000 10000 100000 Concentration (units) Test Statistic, A2 0.416 Critical Value (α=0.10) 1.933 Figure 31. Gompertz CDF fit to data with confidence limits. Sample from the Model CDF? Yes

0.08 2.0 0.06 1.5 0.04 1.0 0.02 0.5 0.00 0.0 0 1 2 3 4 5 -2 -1 0 1 2 Residuals -0.02 -0.5 -0.04 -1.0 -0.06 -1.5 Ordered Standardized Ordered Standardized Residuals -0.08 -2.0 Normal Scores Predictor, X i

Figure 32. Plot of residuals versus toxicity metameter, xi. Figure 33. Normal probability plot of residuals.

1.0 4 4 0.8 3

0.6 3 2

0.4 2

Ordered Ordered Predictors 1 0.2

Observed Proportion Observed Proportion Affected 1

0.0 0 0 0.2 0.4 0.6 0.8 1 0 1 2 3 4 5 Predicted Proportion Affected Quantiles of the Gompertz Model

Figure 34. PP Plot (observed vs. predicted proportion affected) Figure 35. QQ Plot for the Gompertz CDF model Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software

Reverse Log Plotting Model 2 3 Taxon ei ei ei Rank Ordered Data F(xi) F(xN+1i) Svalues Sorted ei (mg/L) Postion Estimates (xi) Tubifex tubifex (oligochaete) 1.717004407 0.045454545 0.00725425 0.038200295 0.001459263 5.57443E05 1 3.876985263 0.00725425 0.997055091 0.977622299 0.056122851 Pimephales promelas (fathead minnow) 2.80902072 0.136363636 0.192486487 0.056122851 0.003149774 0.000176774 2 3.595496222 0.192486487 0.912713824 1.11444341 0.053020861 Euglena gracilis (protist) 2.831756235 0.227272727 0.204974798 0.022297929 0.000497198 1.10865E05 3 3.423245874 0.204974798 0.760902927 1.370797224 0.04907746 Ceriodaphnia dubia (spiny waterflea) 3.006468213 0.318181818 0.325584748 0.00740293 5.48034E05 4.05706E07 4 3.28780173 0.325584748 0.609727945 1.312845987 0.042509637 Girardia dorotocephala (flatworm) 3.088348752 0.409090909 0.398014872 0.011076037 0.000122679 1.35879E06 5 3.262300468 0.398014872 0.580840361 1.465174913 0.00740293 Daphnia magna (waterflea) 3.23749347 0.5 0.553020861 0.053020861 0.002811212 0.000149053 6 3.23749347 0.553020861 0.553020861 1.397602909 0.01006873 Oncorhynchus mykiss (rainbow trout) 3.262300468 0.590909091 0.580840361 0.01006873 0.000101379 1.02076E06 7 3.088348752 0.580840361 0.398014872 1.241856749 0.011076037 Catostomus latipinnis (flannelmouth sucker) 3.28780173 0.681818182 0.609727945 0.072090237 0.005197002 0.000374653 8 3.006468213 0.609727945 0.325584748 1.211797733 0.011824346 Crangonyx pseudogracilis (amphipod) 3.423245874 0.772727273 0.760902927 0.011824346 0.000139815 1.65322E06 9 2.831756235 0.760902927 0.204974798 0.776793291 0.022297929 Gammarus fasciatus (scud) 3.595496222 0.863636364 0.912713824 0.04907746 0.002408597 0.000118208 10 2.80902072 0.912713824 0.192486487 0.527039934 0.038200295 Chironomus tentans (midge) 3.876985263 0.954545455 0.997055091 0.042509637 0.001807069 7.68179E05 11 1.717004407 0.997055091 0.00725425 0.019529892 0.072090237 Sum 0.042576166 0.017748791 7.57419E05 11.41550434 mean 0.003870561 Standard deviation 0.041933278

Quantile Quantile Log 2 4 Standardized Uniform Order 2 Taxon (eieibar) (eieibar) mi mixi mi Function (F Function (F ∂f(phati;,σ)/∂ ∂f(phati;,σ)/∂σ (mg/L) Sorted ei Statistic 1 1 (pi)) (phati)) Tubifex tubifex (oligochaete) 1.717004407 0.001202006 1.44482E06 1.246081709 0.055555556 1.593218818 0.089415982 2.538346202 2.316246716 1.717004407 0.590476301 1.615048913 Pimephales promelas (fathead minnow) 2.80902072 0.003558503 1.26629E05 1.172107291 0.144444444 1.060562244 0.056231923 1.124792272 2.687118298 2.80902072 0.501540012 1.764745332 Euglena gracilis (protist) 2.831756235 0.000352222 1.24061E07 1.078067408 0.233333333 0.727913291 0.035724136 0.529857759 2.869530216 2.831756235 0.524275527 1.835111828 Ceriodaphnia dubia (spiny waterflea) 3.006468213 0.000119536 1.4289E08 0.921441838 0.322222222 0.461493694 0.019617929 0.21297643 2.997387185 3.006468213 0.698987505 2.375846001 Girardia dorotocephala (flatworm) 3.088348752 5.69375E05 3.24188E09 0.084237864 0.411111111 0.224687715 0.001663347 0.050484569 3.099960068 3.088348752 0.780868044 2.629266551 Daphnia magna (waterflea) 3.23749347 0.003198038 1.02274E05 0.332415947 0.5 0 0 0 3.189059864 3.23749347 0.930012761 3.090869964 Oncorhynchus mykiss (rainbow trout) 3.262300468 4.27505E05 1.82761E09 0.356437607 0.588888889 0.224687715 0.002488649 0.050484569 3.271211526 3.262300468 0.95481976 3.16764771 Catostomus latipinnis (flannelmouth sucker) 3.28780173 0.004700459 2.20943E05 0.374282837 0.677777778 0.461493694 0.005456861 0.21297643 3.35126747 3.28780173 0.980321022 3.246574203 Crangonyx pseudogracilis (amphipod) 3.423245874 6.87905E05 4.73213E09 0.62405067 0.766666667 0.727913291 0.016230959 0.529857759 3.434500163 3.423245874 1.115765166 3.665774294 Gammarus fasciatus (scud) 3.595496222 0.002767581 7.6595E06 1.003280885 0.855555556 1.060562244 0.040513791 1.124792272 3.530212313 3.595496222 1.288015514 4.198889713 Chironomus tentans (midge) 3.876985263 0.00211968 4.49304E06 1.811468165 0.944444444 1.593218818 0.114855522 2.538346202 3.672103372 3.876985263 1.569504555 5.070099263 Sum 0.018186504 5.87302E05 0.3821991 8.912914465 mean Standard deviation

Page 3 of 8 Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software

Log 1 1 2 LCL UCL LCL UCL Taxon xi(X'X) xi(X'X) xi' ei(x) ei(x) (mg/L) regression regression conc conc Tubifex tubifex (oligochaete) 1.717004407 6.932702814 2.096051977 0.708370247 0.599242309 0.359091345 1.223959127 2.210049687 16.74785248 162.1995658 Pimephales promelas (fathead minnow) 2.80902072 2.51465466 0.781941578 0.11872782 0.121902422 0.0148602 2.607168795 3.010872646 404.7331665 1025.351205 Euglena gracilis (protist) 2.831756235 2.422671969 0.754582118 0.114594947 0.03777398 0.001426874 2.633448624 3.030063847 429.9803649 1071.676843 Ceriodaphnia dubia (spiny waterflea) 3.006468213 1.71582728 0.544337249 0.093919646 0.009081028 8.24651E05 2.826939105 3.185997321 671.3347146 1534.607518 Girardia dorotocephala (flatworm) 3.088348752 1.384557353 0.44580386 0.090980585 0.011611316 0.000134823 2.911651005 3.2650465 815.9264366 1840.969103 Daphnia magna (waterflea) 3.23749347 0.78115195 0.266326116 0.096698111 0.048433606 0.002345814 3.055328173 3.419658766 1135.868807 2628.20215 Oncorhynchus mykiss (rainbow trout) 3.262300468 0.68078851 0.236473875 0.099035606 0.008911058 7.9407E05 3.077946567 3.446654369 1196.593301 2796.754653 Catostomus latipinnis (flannelmouth sucker) 3.28780173 0.577616239 0.205786171 0.101850732 0.063465741 0.0040279 3.100846023 3.474757437 1261.38024 2983.71568 Crangonyx pseudogracilis (amphipod) 3.423245874 0.029640222 0.042795421 0.123806826 0.011254289 0.000126659 3.217121692 3.629370056 1648.624282 4259.612135 Gammarus fasciatus (scud) 3.595496222 0.667245275 0.164487173 0.168758769 0.065283909 0.004261989 3.354844029 3.836148415 2263.831135 6857.22524 Chironomus tentans (midge) 3.876985263 1.806085531 0.503225405 0.283256711 0.204881891 0.041976589 3.565206339 4.188764187 3674.568423 15444.15625 Sum 0.428414065 mean MSE(x) 0.047601563 Standard deviation (X'X)1 70.23160978 21.3847383 21.3847383 6.520625542 X'X 10.07830214 33.05232794 33.05232794 108.5502271 ∂f(pi;,β)/∂ 0.590476301 0.501540012 0.524275527 0.698987505 0.780868044 0.930012761 0.95481976 0.980321022 1.115765166 1.288015514 1.569504555 ∂f(pi;,β)/∂β 1.615048913 1.764745332 1.835111828 2.375846001 2.629266551 3.090869964 3.16764771 3.246574203 3.665774294 4.198889713 5.070099263

Page 4 of 8 Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software Proportion of Log LCL UCL LCL UCL 1 1 Taxa Affected HCx (mg/L) ∂f(phati;,σ)/∂ ∂f(phati;,σ)/∂σ xi(X'X) (i) xi(X'X) xi' regression regression conc conc 0.001 11.90520286 1.0757368 1.231743908 3.599774362 9.527124832 2.867740477 1.411759329 0.379692337 1.771781263 2.397134139 59.12637628 0.005 39.48174099 1.596396295 0.711084413 1.988331434 7.42065564 2.241189345 0.820485335 1.065765976 2.127026615 11.63498896 133.9758789 0.01 66.24696243 1.82116597 0.486314738 1.292668519 6.511288963 1.970706054 0.619066114 1.36024638 2.282085559 22.92167658 191.4633084 0.02 111.3675831 2.046758795 0.260721914 0.59445795 5.598592009 1.6992322 0.449553532 1.653980611 2.439536978 45.07965787 275.1293853 0.03 151.1524168 2.179415096 0.128065613 0.183886242 5.061894966 1.539596284 0.365144105 1.825426886 2.533403305 66.90011841 341.5099055 0.04 187.9445569 2.274029753 0.033450956 0.108946447 4.679105712 1.425738914 0.311849746 1.946892993 2.601166512 88.48975511 399.177921 0.05 222.7442036 2.347806411 0.040325703 0.337285459 4.38062223 1.336957572 0.274284677 2.041004951 2.654607872 109.9018367 451.4481441 0.06 256.0991816 2.408408191 0.100927483 0.524848175 4.135441296 1.264030613 0.246044481 2.1178297 2.698986682 131.1685446 500.0192007 0.07 288.3520004 2.459922969 0.15244226 0.68428659 3.927024292 1.202038769 0.22389455 2.182732425 2.737113513 152.3114051 545.9005259 0.08 319.7355798 2.504790967 0.197310259 0.823153198 3.745498637 1.148045525 0.205992041 2.238913293 2.77066864 173.3457878 589.7509382 0.09 350.4179065 2.544586291 0.237105582 0.946319862 3.584495861 1.100156635 0.191196097 2.288435229 2.800737353 194.2831913 632.0295046 0.1 380.5255598 2.580383834 0.272903125 1.057113381 3.439667193 1.057078594 0.178755999 2.332706101 2.828061566 215.1325381 673.0720652 0.11 410.1572303 2.612950372 0.305469664 1.157906928 3.307910431 1.017888679 0.168154068 2.372729721 2.853171022 235.9009669 713.1338024 0.12 439.3920127 2.642852158 0.33537145 1.25045306 3.186934645 0.981905473 0.159019811 2.409247087 2.876457229 256.5943486 752.4146262 0.13 468.2947634 2.670519301 0.363038593 1.336082964 3.074999713 0.948611391 0.151079949 2.442820857 2.898217746 277.2176365 791.0751572 0.14 496.9197052 2.696286219 0.388805511 1.415831662 2.97075266 0.917604002 0.144127795 2.473888402 2.918684036 297.7751154 829.2472426 0.15 525.3129399 2.720418099 0.412937391 1.490519913 2.873120595 0.888564185 0.13800369 2.502796498 2.938039699 318.270582 867.0411292 0.16 553.5142496 2.743128806 0.435648098 1.560809629 2.781238271 0.861234578 0.132582061 2.529824789 2.956432822 338.7074811 904.5505092 0.17 581.5584197 2.764593348 0.45711264 1.627242461 2.694397645 0.835404582 0.127762588 2.555202112 2.973984583 359.0890089 941.8561613 0.18 609.4762338 2.784956775 0.477476067 1.690267339 2.612011877 0.810899644 0.123464025 2.579118153 2.990795397 379.4181947 979.0286412 0.19 637.2952339 2.804340671 0.496859962 1.750260561 2.533589071 0.787573455 0.119619788 2.601731936 3.006949405 399.6979643 1016.130307 0.2 665.0403123 2.822847971 0.515367263 1.807540721 2.458712766 0.765302143 0.116174718 2.623178135 3.022517808 419.9311918 1053.216874 0.21 692.7341798 2.840566616 0.533085908 1.862379989 2.387027182 0.743979883 0.113082692 2.643571836 3.037561397 440.1207414 1090.338625 0.22 720.3977401 2.857572342 0.550091634 1.915012767 2.318225909 0.723515536 0.110304812 2.663012198 3.052132486 460.2695008 1127.541371 0.23 748.0503939 2.873930856 0.566450148 1.965642425 2.252043103 0.70383003 0.107808019 2.681585289 3.066276423 480.3804102 1164.867218 0.24 775.7102892 2.889699552 0.582218844 2.014446593 2.188246566 0.6848543 0.105564025 2.699366321 3.080032783 500.4564851 1202.355191 0.25 803.394529 2.90492887 0.597448162 2.061581384 2.126632231 0.666527646 0.10354847 2.716421431 3.093436308 520.5008361 1240.041753 0.26 831.1193454 2.919663391 0.612182683 2.107184778 2.067019729 0.64879642 0.101740257 2.732809105 3.106517678 540.516685 1277.961228 0.27 858.9002483 2.933942728 0.62646202 2.151379376 2.009248798 0.631612954 0.100121022 2.748581335 3.119304122 560.5073793 1316.146163 0.28 886.7521525 2.947802251 0.640321543 2.194274647 1.953176339 0.614934683 0.098674698 2.76378457 3.131819933 580.4764035 1354.627639 0.29 914.6894888 2.961273688 0.65379298 2.235968791 1.898673987 0.598723428 0.097387175 2.778460495 3.144086882 600.4273897 1393.435535 0.3 942.7263004 2.974385623 0.666904915 2.276550275 1.845626098 0.58294479 0.096246006 2.792646676 3.15612457 620.3641267 1432.598758 0.31 970.8763294 2.987163913 0.679683205 2.316099125 1.793928062 0.567567654 0.095240173 2.806377104 3.167950721 640.2905681 1472.145451 0.32 999.1530941 2.999632038 0.692151329 2.354688014 1.743484882 0.552563764 0.094359894 2.81968265 3.179581425 660.2108393 1512.103174 0.33 1027.569959 3.011811399 0.704330691 2.392383181 1.694209971 0.537907366 0.093596456 2.832591449 3.191031349 680.1292448 1552.499072 0.34 1056.140201 3.023721574 0.716240866 2.429245212 1.646024129 0.523574902 0.092942077 2.84512923 3.202313918 700.0502747 1593.360028 0.35 1084.877067 3.035380529 0.727899821 2.465329717 1.598854666 0.509544751 0.092389793 2.857319595 3.213441463 719.9786108 1634.7128 0.36 1113.793832 3.046804808 0.7393241 2.500687902 1.552634645 0.495797004 0.091933358 2.869184258 3.224425359 739.9191341 1676.58416 0.37 1142.903853 3.058009697 0.750528989 2.53536707 1.50730223 0.482313267 0.091567157 2.88074326 3.235276134 759.8769306 1719.001017 0.38 1172.220621 3.069009357 0.761528649 2.569411056 1.462800121 0.469076498 0.09128614 2.892015142 3.246003572 779.8572997 1761.99054

Page 5 of 8 Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software Proportion of Log LCL UCL LCL UCL 1 1 Taxa Affected HCx (mg/L) ∂f(phati;,σ)/∂ ∂f(phati;,σ)/∂σ xi(X'X) (i) xi(X'X) xi' regression regression conc conc 0.39 1201.757814 3.079816955 0.772336247 2.602860608 1.419075054 0.456070853 0.091085757 2.903017107 3.256616803 799.8657611 1805.580279 0.4 1231.529344 3.090444764 0.782964056 2.635753716 1.376077367 0.443281561 0.090961905 2.913765158 3.267124371 819.908064 1849.798279 0.41 1261.549411 3.100904265 0.793423557 2.668125907 1.33376062 0.430694809 0.090910882 2.924274217 3.277534313 839.9901962 1894.673204 0.42 1291.832551 3.111206223 0.803725515 2.700010503 1.292081254 0.41829764 0.090929351 2.934558236 3.287854211 860.1183949 1940.234449 0.43 1322.393691 3.121360769 0.81388006 2.731438855 1.250998288 0.406077866 0.091014298 2.944630286 3.298091251 880.2991578 1986.512264 0.44 1353.248201 3.131377458 0.82389675 2.762440545 1.210473053 0.394023983 0.091163012 2.95450265 3.308252267 900.5392568 2033.537883 0.45 1384.411952 3.14126534 0.833784632 2.793043572 1.170468946 0.382125106 0.091373052 2.964186889 3.318343791 920.8457516 2081.343644 0.46 1415.901372 3.151033003 0.843552294 2.823274521 1.130951218 0.370370898 0.091642225 2.973693918 3.328372087 941.2260064 2129.963135 0.47 1447.733511 3.160688627 0.853207919 2.853158713 1.09188677 0.358751514 0.091968569 2.983034065 3.338343189 961.6877079 2179.431328 0.48 1479.926104 3.170240031 0.862759322 2.882720339 1.053243977 0.347257548 0.092350336 2.992217123 3.348262938 982.2388848 2229.784737 0.49 1512.497643 3.179694707 0.872213998 2.911982594 1.014992521 0.335879981 0.092785975 3.001252405 3.358137008 1002.887931 2281.061573 0.5 1545.467454 3.189059864 0.881579156 2.940967788 0.977103238 0.32461014 0.093274119 3.010148788 3.36797094 1023.64363 2333.301926 0.51 1578.855776 3.19834246 0.890861752 2.969697456 0.939547977 0.313439651 0.093813578 3.018914757 3.377770164 1044.515181 2386.547947 0.52 1612.683851 3.207549237 0.900068529 2.998192461 0.902299464 0.302360402 0.094403325 3.027558441 3.387540032 1065.512236 2440.84405 0.53 1646.97402 3.216686749 0.90920604 3.026473091 0.865331183 0.291364505 0.095042494 3.036087657 3.39728584 1086.644926 2496.23714 0.54 1681.749833 3.225761393 0.918280685 3.054559147 0.828617248 0.28044426 0.095730367 3.044509934 3.407012853 1107.923906 2552.77685 0.55 1717.036157 3.234779441 0.927298732 3.082470035 0.792132291 0.269592124 0.096466375 3.052832554 3.416726328 1129.360395 2610.515809 0.56 1752.859314 3.243747061 0.936266353 3.11022485 0.755851351 0.258800671 0.09725009 3.06106258 3.426431542 1150.966226 2669.509937 0.57 1789.247216 3.25267035 0.945189642 3.137842461 0.719749764 0.248062565 0.098081226 3.069206885 3.436133816 1172.753896 2729.81877 0.58 1826.229523 3.261555359 0.954074651 3.165341595 0.68380305 0.237370524 0.098959636 3.077272181 3.445838538 1194.736634 2791.505821 0.59 1863.837822 3.27040812 0.962927412 3.192740921 0.647986804 0.22671729 0.099885312 3.085265049 3.455551192 1216.928462 2854.638982 0.6 1902.10582 3.279234674 0.971753966 3.220059136 0.612276586 0.216095593 0.100858386 3.093191964 3.465277385 1239.344272 2919.290976 0.61 1941.069565 3.2880411 0.980560392 3.247315055 0.576647802 0.205498118 0.101879136 3.101059326 3.475022874 1261.999916 2985.539863 0.62 1980.767695 3.296833544 0.989352836 3.274527699 0.541075585 0.194917468 0.102947982 3.108873487 3.484793602 1284.9123 3053.46961 0.63 2021.241711 3.305618252 0.998137544 3.3017164 0.505534668 0.184346128 0.104065502 3.116640777 3.494595726 1308.099493 3123.170734 0.64 2062.536303 3.314401601 1.006920893 3.328900897 0.469999245 0.173776422 0.105232428 3.124367543 3.50443566 1331.580855 3194.741037 0.65 2104.699703 3.32319014 1.015709432 3.356101453 0.43444283 0.163200473 0.106449663 3.132060168 3.514320111 1355.377177 3268.286433 0.66 2147.784096 3.331990622 1.024509914 3.383338976 0.398838092 0.15261015 0.107718288 3.139725118 3.524256126 1379.510842 3343.921904 0.67 2191.846095 3.340810056 1.033329348 3.410635154 0.36315668 0.141997021 0.109039575 3.147368968 3.534251144 1404.006015 3421.772594 0.68 2236.947281 3.349655749 1.042175041 3.438012605 0.32736903 0.131352292 0.110415004 3.154998449 3.544313049 1428.888854 3501.975064 0.69 2283.154828 3.358535363 1.051054655 3.465495041 0.291444142 0.120666744 0.111846279 3.162620485 3.554450242 1454.187759 3584.678756 0.7 2330.542232 3.367456977 1.059976269 3.493107467 0.255349334 0.109930653 0.113335352 3.170242247 3.564671707 1479.933658 3670.047684 0.71 2379.190159 3.376429155 1.068948447 3.520876388 0.219049956 0.099133716 0.114884449 3.177871208 3.574987102 1506.160342 3758.262422 0.72 2429.187442 3.385461027 1.077980319 3.548830064 0.182509066 0.088264943 0.116496101 3.1855152 3.585406854 1532.904857 3849.52243 0.73 2480.632251 3.394562386 1.087081678 3.5769988 0.145687052 0.077312552 0.118173179 3.193182491 3.59594228 1560.207967 3944.048805 0.74 2533.633488 3.403743791 1.096263083 3.60541528 0.108541189 0.066263834 0.119918942 3.200881865 3.606605717 1588.114697 4042.087556 0.75 2588.312447 3.413016701 1.105535993 3.634114968 0.071025116 0.055105001 0.121737088 3.208622719 3.617410682 1616.674988 4143.913509 0.76 2644.804806 3.422393625 1.114912917 3.663136582 0.033088225 0.043820999 0.123631817 3.21641518 3.628372071 1645.944474 4249.835017 0.77 2703.263046 3.431888308 1.124407599 3.692522656 0.005325087 0.03239529 0.125607912 3.224270238 3.639506377 1675.985427 4360.199663 0.78 2763.859392 3.441515945 1.134035237 3.722320227 0.044276306 0.020809586 0.127670833 3.232199912 3.650831978 1706.867905 4475.401241

Page 6 of 8 Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software Proportion of Log LCL UCL LCL UCL 1 1 Taxa Affected HCx (mg/L) ∂f(phati;,σ)/∂ ∂f(phati;,σ)/∂σ xi(X'X) (i) xi(X'X) xi' regression regression conc conc 0.79 2826.789432 3.451293459 1.143812751 3.752581667 0.08383389 0.009043523 0.12982683 3.240217449 3.662369469 1738.671154 4595.888343 0.8 2892.276607 3.461239825 1.153759117 3.783365704 0.124074611 0.002925733 0.132083094 3.248337567 3.674142083 1771.485359 4722.175055 0.81 2960.577843 3.471376485 1.163895776 3.8147387 0.165085216 0.015123985 0.134447935 3.256576761 3.686176208 1805.413813 4854.854382 0.82 3031.990677 3.481727862 1.174247153 3.846776247 0.20696452 0.027580623 0.136931011 3.264953679 3.698502044 1840.575678 4994.615313 0.83 3106.862407 3.49232202 1.184841312 3.879565204 0.249826061 0.04032942 0.139543624 3.273489608 3.711154433 1877.109501 5142.26475 0.84 3185.601971 3.503191511 1.195710803 3.913206317 0.293801535 0.053409546 0.142299096 3.282209094 3.724173929 1915.177778 5298.75609 0.85 3268.69562 3.514374481 1.206893773 3.947817647 0.339045273 0.066866907 0.145213275 3.291140755 3.737608208 1954.972958 5465.227032 0.86 3356.727942 3.525916144 1.218435436 3.983539132 0.385740199 0.08075591 0.148305198 3.300318356 3.751513931 1996.725463 5643.050426 0.87 3450.410571 3.537870776 1.230390068 4.020538759 0.434105905 0.095141873 0.151598004 3.309782275 3.765959277 2040.714615 5833.903979 0.88 3550.622281 3.550304474 1.242823766 4.059021099 0.484409803 0.110104335 0.155120197 3.31958151 3.781027439 2087.283834 6039.867879 0.89 3658.466323 3.563299062 1.255818353 4.099239392 0.536982932 0.12574176 0.158907447 3.329776538 3.796821585 2136.862307 6263.564946 0.9 3775.354817 3.576957774 1.269477066 4.141513153 0.592242957 0.142178378 0.163005226 3.340443468 3.81347208 2189.99674 6508.367677 0.91 3903.13717 3.591413814 1.283933106 4.186254648 0.650728788 0.159574486 0.167472802 3.351680277 3.831147351 2247.399486 6778.714625 0.92 4044.303447 3.606843734 1.299363025 4.234010301 0.713154711 0.178142539 0.172389517 3.363616569 3.850070898 2310.024412 7080.613645 0.93 4202.322441 3.623489372 1.316008664 4.285528611 0.780499158 0.198173565 0.17786517 3.376429561 3.870549184 2379.192383 7422.48253 0.94 4382.238555 3.641696016 1.334215307 4.341878234 0.85415907 0.220083072 0.184058205 3.390371855 3.893020177 2456.811603 7816.641184 0.95 4591.81025 3.661983933 1.354503225 4.404669409 0.936239343 0.244497143 0.191210123 3.405823475 3.918144391 2545.795271 8282.174774 0.96 4843.916654 3.685196662 1.377715954 4.476512884 1.030152733 0.272430872 0.199717544 3.423399606 3.946993718 2650.938216 8851.028067 0.97 5162.440077 3.712855024 1.405374315 4.562115608 1.142052136 0.305714387 0.210306363 3.444207491 3.981502556 2781.041638 9583.023565 0.98 5600.266501 3.748208694 1.440727986 4.671535341 1.285084999 0.348258281 0.224557055 3.470608349 4.02580904 2955.346104 10612.2883 0.99 6322.875215 3.800914611 1.493433903 4.834660334 1.498321078 0.411683517 0.247293523 3.509599494 4.092229727 3232.95377 12366.01382 0.995 7018.051534 3.846216553 1.538735845 4.97487 1.681602371 0.46619896 0.268262622 3.542801773 4.149631333 3489.809922 14113.38968 0.999 8549.111126 3.931920962 1.624440254 5.240125442 2.028342802 0.569333918 0.31154055 3.604946419 4.258895505 4026.673526 18150.78888

Page 7 of 8 Appendix E. Statistical Analysis of Acute Species Sensitivity Distribution Using SSD Master Software D'Agostino and Pearson's, K2 ShapiroFrancia, W' s2 0.0017584 W' 0.901177517

k3 1.9911E05 X 2.602104727

k4 8.97356E06 λhat 0.110307807

g1 0.270033077 y 2.042609003

g2 2.902215966 yhat 2.46123872

root b1 0.231719793 σyhat 0.443478379 A 0.408715297 z 0.94396872 B 3.383333333 A 0.827407183 C 1.183269719 p 0.172592817 D 1.087782018 E 3.447440185 F 0.123723231 G 0.589285714 H 2.26839155 J 1.47636828 K 22.46453508 L 0.521580465

Zg1 0.425447689

Zg2 1.861555445

Page 8 of 8 EKATI DIAMOND MINE Site Specific Water Quality Objective for Molybdenum, 2011

Appendix F Statistical Analysis of Chronic Species Sensitivity Distribution Using SSD Master Software

Appendix F. Statistical Analysis of Chronic Species Sensitivity Distribution Using SSD Master Software

Model Normal Logistic Gompertz Weibull Fisher-Tippett ∑ei2 0.0324 0.0344 0.0443 0.0362 0.0283 MSE 0.0041 0.0043 0.0055 0.0045 0.0035 Normal residuals? D'Agostino-Pearson (n>20) Yes Yes Yes Yes Yes Normal residuals? Shapiro-Francia (n>7) Yes Yes Yes Yes Yes Data from specified distribution? Anderson-Darling (n>5) Yes Yes Yes Yes Yes A2 (AndersonDarling) 0.291 0.309 0.367 0.317 0.269 HC5(mg/L) 19.38 17.07 10.89 16.36 26.46 Lower confidence limit on the mean (expected HC5) 13.63 9.55 4.14 10.32 16.11 Upper confidence limit on the mean (expected HC5) 27.55 30.54 28.64 25.95 43.44

Model Parameter Estimates Shape Shape Scale Scale Location Location Model notation Estimate Notation Estimate Notation Estimate Normal σ 0.382554053 1.91650943 Logistic σ or s 0.231406726 1.91370982 Gompertz σ or s 0.349948249 2.07628039 Weibull κ 5.6170557 λ 2.059753974 FisherTippett b or s 0.317629865 or L 1.77103463

1.0

0.8

0.6

0.4 Proportion Affected of Proportion Taxa

0.2 Normal Logistic Gompertz Weibull FisherTippett 0.0 0.1 1 10 100 1000 10000 Molybdenum Concentration (mg/L) Appendix F. Statistical Analysis of Chronic Species Sensitivity Distribution Using SSD Master Software

Model 1 Normal

Parameter Estimates Variables Statistic Values 1.0

2 1.916509428 ∑ei 0.032437176 0.8 σ 0.382554053 MSE 0.004054647

0.6 Residual Normality Test Test StatisticCritical Value (α=0.05) Normal? PValue 0.4 2 2 D'AgostinoPearson, K (n≥20) 3.158 χ (2df) 5.991 Yes 0.2062 Normal Model ShapiroFrancia, W' (7≤n) 0.833 z 1.645 Yes 0.7975 0.2 Confidence Limits Proportion of Taxa Affected of Taxa Proportion AndersonDarling GoodnessofFit (n≥5) 0.0 Test Statistic, A2 0.291 1 10 100 1000 10000 Concentration (units) Critical Value (α=0.10) 1.933 Sample from the Model CDF? Yes Figure 11. Normal CDF fit to data with confidence limits.

0.12 2.0 0.10 1.5 0.08 1.0 0.06 0.04 0.5 0.02 0.0 0.00 -2 -1 0 1 2 Residuals -0.02 0 0.5 1 1.5 2 2.5 3 -0.5 -0.04 -1.0 -0.06 -1.5

-0.08 Residuals Standardized Ordered -0.10 -2.0

Predictor, X i Normal Scores

Figure 12. Plot of residuals versus toxicity metameter, xi. Figure 13. Normal probability plot of residuals.

1.0 3

3 0.8 2 0.6 2 0.4 1 Ordered Predictors Ordered 0.2 1 Observed Proportion Affected Proportion Observed 0.0 0 0 0.2 0.4 0.6 0.8 1 0 0.5 1 1.5 2 2.5 3 Predicted Proportion Affected Quantiles of the Normal Model

Figure 14. PP Plot (observed vs. predicted proportion affected) Figure 15. QQ Plot for the Normal CDF model

Page 2 of 5 Appendix F. Statistical Analysis of Chronic Species Sensitivity Distribution Using SSD Master Software

Log Plotting 2 3 2 4 Taxon Model Estimate ei ei ei Rank F(xi) F(xN+1i) Svalues Sorted ei (eieibar) (eieibar) Standardized Sorted ei Uniform Order Statistic (mg/L) Postion Reverse Ordered Data (xi) Pseudokirchneriella subcapitata (green algae) 1.400 0.050 0.088 0.038 0.001470 0.000056 1 2.3829 0.088 0.888614766 0.462125999 0.084 0.00120 0.0000014283 1.331 0.061 Oncorhynchus mykiss (rainbow trout) 1.635 0.150 0.231 0.081 0.006608 0.000537 2 2.3249 0.231 0.857134976 1.022980865 0.081 0.00601 0.0000361031 1.294 0.159 Chlorella regularis (green alga) 1.699 0.250 0.285 0.035 0.001211 0.000042 3 2.2869 0.285 0.833532381 1.524466921 0.038 0.00096 0.0000009261 0.577 0.256 Ceriodaphnia dubia (spiny waterflea) 1.710 0.350 0.295 0.055 0.003055 0.000169 4 2.0842 0.295 0.669449518 1.630099032 0.035 0.00349 0.0000121599 0.518 0.354 Pimephales promelas (fathead minnow) 1.776 0.450 0.357 0.093 0.008618 0.000800 5 1.9479 0.357 0.53269896 1.6113013 0.019 0.00933 0.0000871099 0.262 0.451 Daphnia magna (waterflea) 1.948 0.550 0.533 0.017 0.000299 0.000005 6 1.7765 0.533 0.357166517 1.178835211 0.007 0.00044 0.0000001973 0.056 0.549 Chironomus riparius (midge) 2.084 0.650 0.669 0.019 0.000378 0.000007 7 1.7101 0.669 0.294723687 0.975604681 0.017 0.00025 0.0000000604 0.352 0.646 Brachionus calyciflorus (rotifer) 2.287 0.750 0.834 0.084 0.006978 0.000583 8 1.6990 0.834 0.284796789 0.775906941 0.055 0.00636 0.0000404647 0.986 0.744 Lymnaea stagnalis (snail) 2.325 0.850 0.857 0.007 0.000051 0.000000 9 1.6355 0.857 0.231290396 0.709243201 0.061 0.00001 0.0000000001 1.088 0.841 Lemna minor (duckweed) 2.383 0.950 0.889 0.061 0.003768 0.000231 10 1.3997 0.889 0.088345547 0.400112871 0.093 0.00425 0.0000180277 1.613 0.939 Sum 5.000 5.037753536 0.037753536 0.032437176 2.0847E05 10.29067702 0.03229 0.00020 mean 0.004 Standard deviation 0.059902367

2 Quantile Quantile Plotting Position 2 2 mi mixi m Probit Weight, w nw nwx nwx Snw(xx ) v(m) sm LCL UCL LCL UCL Taxon i Function (F Function (F Roundoff bar regression regression conc conc Pseudokirchneriella subcapitata (green algae) 1.546635271 0.129194126 2.392080663 1.287264006 1.399673721 0.050 3.3 0.208 2.08 2.911321341 8.476 787.670 0.003088431 0.055573653 1.246761504 1.552585938 17.65068256 35.69323723 Oncorhynchus mykiss (rainbow trout) 1.000490546 0.081330272 1.000981332 1.520017634 1.635483747 0.150 4 0.439 4.39 7.179773649 51.549 787.670 0.003043208 0.055165277 1.483695186 1.787272307 30.45756546 61.27344625 Chlorella regularis (green alga) 0.655423505 0.025132573 0.429579971 1.65848064 1.698970004 0.250 4.3 0.532 5.32 9.038520423 81.695 787.670 0.003025855 0.055007771 1.547614823 1.850325185 35.28700698 70.84760692 Ceriodaphnia dubia (spiny waterflea) 0.37546177 0.013064864 0.140971541 1.769103522 1.710069095 0.350 4.6 0.601 6.01 10.27751526 105.627 787.670 0.003017111 0.054928233 1.558932767 1.861205422 36.21869238 72.64494884 Pimephales promelas (fathead minnow) 0.122580844 0.002384138 0.015026063 1.86843717 1.776478217 0.450 4.9 0.634 6.34 11.26287189 126.852 787.670 0.003013134 0.05489202 1.625441529 1.927514905 42.21254423 84.62816125 Daphnia magna (waterflea) 0.122580844 0.000874611 0.015026063 1.964581685 1.947900332 0.550 5.1 0.634 6.34 12.34968811 152.515 787.670 0.003012777 0.054888766 1.796872599 2.098928066 62.64300731 125.5821939 Chironomus riparius (midge) 0.37546177 0.006495879 0.140971541 2.063915334 2.084218687 0.650 5.4 0.601 6.01 12.52615431 156.905 787.670 0.003016015 0.054918259 1.9331098 2.235327573 85.72545532 171.9204634 Brachionus calyciflorus (rotifer) 0.655423505 0.036229395 0.429579971 2.174538215 2.286905353 0.750 5.7 0.532 5.32 12.16633648 148.020 787.670 0.003023937 0.054990338 2.135598141 2.438212565 136.6463832 274.291636 Lymnaea stagnalis (snail) 1.000490546 0.061415346 1.000981332 2.313001221 2.324899497 0.850 6 0.439 4.39 10.20630879 104.169 787.670 0.003040261 0.055138562 2.173184442 2.476614552 148.9993736 299.650186 Lemna minor (duckweed) 1.546635271 0.14357954 2.392080663 2.545754849 2.382917135 0.950 6.6 0.238 2.38 5.671342782 32.164 787.670 0.003083754 0.055531562 2.230120733 2.535713537 169.8715827 343.33141 Sum 0.497951522 7.95727914 48.58 93.58983303 967.971 mean xbar 1.926509531 Standard deviation

Page 3 of 5 Appendix F. Statistical Analysis of Chronic Species Sensitivity Distribution Using SSD Master Software

Log of 2 LCL UCL LCL UCL Proportion of Taxa Affected HCx Snw(xx ) v(m) sm (mg/L) bar regression regression conc conc 0.001 5.424110579 0.734328535 787.670 0.003276581 0.057241431 0.576827387 0.891829683 3.774221521 7.795243444 0.005 8.533270016 0.931115488 787.670 0.003196598 0.056538464 0.775548572 1.086682404 5.964150195 12.20906496 0.01 10.6305472 1.02655562 787.670 0.003162988 0.056240452 0.87180869 1.18130255 7.444039869 15.18107584 0.02 13.51572847 1.130839458 787.670 0.003130134 0.055947604 0.976898305 1.284780611 9.481964071 19.26551448 0.03 15.73998124 1.19700421 787.670 0.003111385 0.05577979 1.043524802 1.350483619 11.05413595 22.41215508 0.04 17.65132762 1.246777376 787.670 0.003098353 0.055662848 1.093619735 1.399935017 12.40565602 25.11510606 0.05 19.37599467 1.287264006 787.670 0.003088431 0.055573653 1.134351789 1.440176223 13.62547933 27.55346511 0.06 20.97608759 1.321724488 787.670 0.003080466 0.055501944 1.16900958 1.474439395 14.75739088 29.81531452 0.07 22.48741779 1.351939589 787.670 0.003073845 0.055442267 1.199388883 1.504490294 15.82664582 31.95142955 0.08 23.9328053 1.378993608 787.670 0.003068205 0.055391377 1.226582926 1.531404289 16.84934125 33.99415806 0.09 25.32784009 1.403598156 787.670 0.003063311 0.055347188 1.251309061 1.55588725 17.83647631 35.96559503 0.1 26.68373889 1.426246682 787.670 0.003059006 0.055308279 1.274064649 1.578428716 18.79596593 37.88163503 0.11 28.0089046 1.447296124 787.670 0.003055175 0.055273637 1.295209407 1.599382842 19.73374023 39.75418384 0.12 29.30984139 1.467013468 787.670 0.003051736 0.055242521 1.31501237 1.619014567 20.65438983 41.59245611 0.13 30.59172285 1.485603936 787.670 0.003048626 0.055214364 1.33368031 1.637527562 21.56156649 43.40378086 0.14 31.85876126 1.503228885 787.670 0.003045796 0.055188732 1.351375789 1.655081982 22.45824362 45.19412498 0.15 33.11445669 1.520017634 787.670 0.003043208 0.055165277 1.368229073 1.671806195 23.34689195 46.96844635 0.16 34.36177059 1.536075534 787.670 0.00304083 0.055143722 1.384346281 1.687804787 24.22960204 48.73093979 0.17 35.60324993 1.551489643 787.670 0.003038638 0.055123842 1.399815092 1.703164194 25.10817183 50.4852131 0.18 36.8411182 1.566332803 787.670 0.00303661 0.055105448 1.414708864 1.717956743 25.9841709 52.23441593 0.19 38.07734351 1.580666642 787.670 0.00303473 0.055088384 1.429089653 1.732243631 26.85898846 53.98133631 0.2 39.31369045 1.594543814 787.670 0.003032982 0.05507252 1.443010475 1.746077152 27.73387 55.72847412 0.21 40.55176031 1.608009711 787.670 0.003031355 0.055057743 1.456517033 1.759502389 28.60994567 57.47809813 0.22 41.79302281 1.621103784 787.670 0.003029837 0.055043957 1.469649038 1.772558529 29.48825262 59.23229082 0.23 43.03884134 1.633860571 787.670 0.00302842 0.055031079 1.482441259 1.785279883 30.36975292 60.99298433 0.24 44.29049353 1.64631052 787.670 0.003027095 0.055019038 1.494924338 1.797696701 31.25534794 62.76198943 0.25 45.54918808 1.65848064 787.670 0.003025855 0.055007771 1.507125459 1.809835821 32.14589036 64.54101946 0.26 46.8160788 1.670395035 787.670 0.003024695 0.054997224 1.519068876 1.821721195 33.04219396 66.33171018 0.27 48.09227638 1.682075334 787.670 0.003023608 0.054987347 1.530776351 1.833374318 33.94504205 68.13563654 0.28 49.37885859 1.693541047 787.670 0.003022591 0.054978099 1.542267511 1.844814583 34.85519454 69.95432698 0.29 50.67687899 1.70480986 787.670 0.003021639 0.054969441 1.553560148 1.856059573 35.77339417 71.78927591 0.3 51.98737464 1.715897886 787.670 0.003020749 0.054961339 1.564670465 1.867125307 36.70037193 73.64195457 0.31 53.311373 1.726819868 787.670 0.003019916 0.054953764 1.57561329 1.878026445 37.63685189 75.51382084 0.32 54.6498981 1.737589356 787.670 0.003019139 0.054946688 1.586402247 1.888776466 38.58355562 77.40632801 0.33 56.0039763 1.748218863 787.670 0.003018413 0.054940089 1.597049913 1.899387813 39.54120617 79.32093291 0.34 57.37464162 1.758719986 787.670 0.003017738 0.054933943 1.607567945 1.909872026 40.51053187 81.25910347 0.35 58.76294074 1.769103522 787.670 0.003017111 0.054928233 1.617967194 1.920239849 41.49226985 83.2223259 0.36 60.16993793 1.779379563 787.670 0.003016529 0.05492294 1.628257799 1.930501327 42.48716952 85.21211159 0.37 61.59671974 1.789557585 787.670 0.003015992 0.054918049 1.638449278 1.940665892 43.49599582 87.23000385 0.38 63.04439974 1.799646514 787.670 0.003015498 0.054913546 1.648550596 1.950742432 44.51953261 89.27758458 0.39 64.51412316 1.809654799 787.670 0.003015044 0.05490942 1.658570236 1.960739362 45.55858592 91.35648096 0.4 66.00707172 1.819590467 787.670 0.003014631 0.054905658 1.668516254 1.970664679 46.61398732 93.46837222 0.41 67.52446852 1.829461175 787.670 0.003014257 0.054902251 1.678396335 1.980526014 47.68659738 95.61499666 0.42 69.0675831 1.839274259 787.670 0.003013921 0.054899191 1.688217839 1.990330679 48.77730923 97.79815884 0.43 70.63773678 1.849036776 787.670 0.003013622 0.05489647 1.697987843 2.000085709 49.88705228 100.0197372 0.44 72.23630821 1.858755542 787.670 0.00301336 0.054894082 1.707713182 2.009797903 51.01679617 102.2816918 0.45 73.86473942 1.86843717 787.670 0.003013134 0.05489202 1.717400482 2.019473858 52.16755493 104.5860734 0.46 75.52454209 1.878088101 787.670 0.003012943 0.054890281 1.727056199 2.029120003 53.34039148 106.9350318 0.47 77.21730443 1.887714637 787.670 0.003012787 0.05488886 1.736686645 2.038742629 54.53642239 109.3308259 0.48 78.9446986 1.897322971 787.670 0.003012666 0.054887754 1.746298021 2.048347921 55.75682311 111.7758346 0.49 80.70848872 1.906919215 787.670 0.003012579 0.054886962 1.755896445 2.057941986 57.00283358 114.2725676 0.5 82.51053965 1.916509428 787.670 0.003012526 0.054886482 1.765487979 2.067530876 58.27576439 116.8236783 0.51 84.3528266 1.92609964 787.670 0.003012507 0.054886313 1.775078656 2.077120624 59.57700352 119.4319777 0.52 86.23744564 1.935695884 787.670 0.003012523 0.054886455 1.784674508 2.08671726 60.90802371 122.1004488 0.53 88.1666254 1.945304218 787.670 0.003012573 0.05488691 1.79428159 2.096326847 62.27039064 124.8322639 0.54 90.14273991 1.954930754 787.670 0.003012657 0.054887679 1.803906009 2.105955499 63.66577198 127.6308023 0.55 92.1683229 1.964581685 787.670 0.003012777 0.054888766 1.813553952 2.115609419 65.09594734 130.4996715 0.56 94.24608375 1.974263313 787.670 0.003012931 0.054890172 1.82323171 2.125294916 66.56281951 133.4427293 0.57 96.37892527 1.983982079 787.670 0.003013121 0.054891903 1.832945714 2.135018444 68.06842688 136.4641092 0.58 98.56996362 1.993744596 787.670 0.003013347 0.054893963 1.842702562 2.144786631 69.6149574 139.5682493 0.59 100.8225507 2.003557681 787.670 0.00301361 0.054896359 1.852509053 2.154606308 71.20476431 142.759924 0.6 103.1402996 2.013428389 787.670 0.003013911 0.054899098 1.862372225 2.164484552 72.84038379 146.04428 0.61 105.5271128 2.023364056 787.670 0.00301425 0.054902188 1.872299392 2.174428721 74.52455503 149.4268774 0.62 107.9872151 2.033372341 787.670 0.003014629 0.054905637 1.882298184 2.184446498 76.26024291 152.9137356 0.63 110.52519 2.04346127 787.670 0.003015049 0.054909458 1.892376601 2.194545939 78.05066386 156.5113866 0.64 113.1460226 2.053639292 787.670 0.00301551 0.054913661 1.902543059 2.204735525 79.89931547 160.2269349 0.65 115.8551473 2.063915334 787.670 0.003016015 0.054918259 1.912806447 2.21502422 81.81001031 164.0681269 0.66 118.6585042 2.074298869 787.670 0.003016565 0.054923268 1.9231762 2.225421538 83.78691505 168.0434303 0.67 121.5626033 2.084799992 787.670 0.003017163 0.054928705 1.933662365 2.235937619 85.83459551 172.1621268 0.68 124.5745992 2.095429499 787.670 0.003017809 0.054934587 1.944275687 2.24658331 87.9580691 176.4344185 0.69 127.7023789 2.106198988 787.670 0.003018506 0.054940935 1.955027708 2.257370268 90.16286589 180.871553 0.7 130.9546635 2.117120969 787.670 0.003019258 0.054947774 1.965930874 2.268311065 92.45510018 185.4859696 0.71 134.3411293 2.128208995 787.670 0.003020066 0.054955128 1.976998665 2.279419325 94.84155477 190.2914716 0.72 137.8725501 2.139477808 787.670 0.003020934 0.054963026 1.988245745 2.290709871 97.32978079 195.3034304 0.73 141.5609671 2.150943521 787.670 0.003021866 0.054971502 1.999688136 2.302198906 99.92821643 200.5390281 0.74 145.4198927 2.16262382 787.670 0.003022866 0.054980592 2.011343423 2.313904216 102.6463293 206.0175491 0.75 149.4645556 2.174538215 787.670 0.003023937 0.054990338 2.023231003 2.325845427 105.4947879 211.7607307 0.76 153.712199 2.186708336 787.670 0.003025086 0.055000786 2.035372376 2.338044295 108.48567 217.7931897 0.77 158.182445 2.199158284 787.670 0.003026319 0.05501199 2.047791496 2.350525072 111.6327174 224.142944 0.78 162.8977446 2.211915071 787.670 0.003027642 0.05502401 2.060515209 2.363314934 114.9516498 230.8420561 0.79 167.8839365 2.225009144 787.670 0.003029062 0.055036917 2.073573767 2.37644452 118.4605562 237.9274338 0.8 173.1709508 2.238475041 787.670 0.00303059 0.055050791 2.087001491 2.389948592 122.1803854 245.4418368 0.81 178.7937006 2.252352213 787.670 0.003032234 0.055065725 2.100837571 2.403866856 126.135569 253.435154 0.82 184.793228 2.266686052 787.670 0.003034008 0.055081829 2.115127101 2.418245003 130.3548219 261.9660447 0.83 191.2181941 2.281529212 787.670 0.003035925 0.055099229 2.129922382 2.433136042 134.8721816 271.1040728 0.84 198.1268438 2.296943321 787.670 0.003038003 0.05511808 2.145284624 2.448602018 139.7283801 280.9325222 0.85 205.5896377 2.313001221 787.670 0.003040261 0.055138562 2.161286167 2.464716276 144.9726797 291.5521684 0.86 213.6928394 2.32978997 787.670 0.003042725 0.055160897 2.17801346 2.48156648 150.665376 303.0864214 0.87 222.5435026 2.347414919 787.670 0.003045424 0.055185356 2.19557111 2.499258728 156.8812748 315.688476 0.88 232.2765607 2.366005387 787.670 0.003048395 0.055212276 2.214087507 2.517923267 163.714636 329.5514805 0.89 243.0651698 2.385722731 787.670 0.003051688 0.055242084 2.233722835 2.537722627 171.2863814 344.9233751 0.9 255.1362529 2.406772173 787.670 0.003055362 0.055275329 2.2546808 2.558863546 179.7549257 362.1292005 0.91 268.794699 2.4294207 787.670 0.003059499 0.055312741 2.277226388 2.581615011 189.3330314 381.6058385 0.92 284.4626474 2.454025248 787.670 0.00306421 0.055355306 2.301713818 2.606336677 200.3151599 403.9584313 0.93 302.7465945 2.481079267 787.670 0.003069649 0.055404414 2.328632715 2.633525818 213.1241749 430.0567991 0.94 324.5595312 2.511294367 787.670 0.003076045 0.055462107 2.358689072 2.663899663 228.3963041 461.2110066 0.95 351.3620472 2.545754849 787.670 0.003083754 0.055531562 2.392958447 2.698551251 247.1487663 499.5181246 0.96 385.6927536 2.586241479 787.670 0.003093375 0.05561812 2.433206911 2.739276048 271.1483155 548.6255737 0.97 432.5284162 2.636014645 787.670 0.003106038 0.055731837 2.482667181 2.789362109 303.8555556 615.6900123 0.98 503.708636 2.702179397 787.670 0.003124295 0.055895396 2.548381896 2.855976898 353.4938769 717.75611 0.99 640.4175652 2.806463235 787.670 0.003156374 0.056181619 2.651878186 2.961048284 448.6195405 914.2148765 0.995 797.8171488 2.901903367 787.670 0.003189274 0.056473661 2.746514756 3.057291978 557.8465557 1141.016641 0.999 1255.134654 3.098690321 787.670 0.003267795 0.057164635 2.94140048 3.255980161 873.7767401 1802.935381

Page 4 of 5 Appendix F. Statistical Analysis of Chronic Species Sensitivity Distribution Using SSD Master Software

D'Agostino and Pearson's, K2 ShapiroFrancia, W' s2 0.003588294 W' 0.965

k3 4.67938E05 X 2.697414907

k4 3.50974E05 λhat 0.132334195

g1 0.217698785 y 2.705593825

g2 2.725833877 yhat 2.350726597

root b1 0.183579735 σyhat 0.426228659 A 0.316863444 z 0.83257477 B 3.320433437 A 0.202542296 C 1.154267131 p 0.797457704 D 1.074368248 E 3.733714201 F 0.088002263 G 0.569612206 H 2.042972749 J 1.396210787 K 24.21741967 L 0.558526918

Zg1 0.328152669

Zg2 1.746387606

Page 5 of 5