2017 AIR QUALITY METEOROLOGICAL MONITORING AND … · 2018. 11. 23. · Snap Lake Mine - ii - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

2017 AIR QUALITY METEOROLOGICAL

MONITORING AND EMISSIONS REPORT

Snap Lake Mine 2018

Snap Lake Mine - i - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

REVISION HISTORY

No previous versions

Snap Lake Mine - ii - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

EXECUTIVE SUMMARY

De Beers Canada Inc. (De Beers) owns and operates the Snap Lake Mine (Mine), a diamond mine located approximately 220 kilometres (km) northeast of Yellowknife, Northwest Territories. The Mine is located 30 km south of MacKay Lake and 100 km south of Lac de Gras. Final regulatory approvals for construction and operation of the Mine were granted in May 2004, and construction began in April 2005. The first diamonds were recovered in August 2007, and commercial production was achieved in early 2008. On December 4, 2015, De Beers announced that it would be suspending operations at Snap Lake Mine, and that the Mine would be placed under “care and maintenance”. An Extended Care and Maintenance Plan was submitted to the Mackenzie Valley Land and Water Board (MVLWB) in April 2016 (De Beers 2016). In December 2017 De Beers announced that the Mine will begin preparations for final closure.

Why Conduct Air Quality and Meteorological monitoring at Snap Lake?

The principal objective of the Air Quality, Meteorological Monitoring and Emissions Reporting Annual Summary is to comply with the Surveillance Network Program (SNP) described in Section C of the SNP, Annex A to Water Licence MV2011L2-0004, Article VI Section 6.3 Items d) and e) and Article VI Section 7.2 part a) of the Environmental Agreement, and related corporate commitments including the Snap Lake Environmental Management System.

This report provides the results of the air quality and meteorological monitoring programs that were active at Snap Lake during 2017. This document fulfills the annual reporting requirements outlined in the Air Quality and Emissions Management and Monitoring Plan(De Beers, 2017). Changes to the original Plan (De Beers, 2005) were made in 2007 and 2008 to align with design recommendations from the Government of the Northwest Territories (GNWT) Ministry of Environment and Natural Resources and Environment and Climate Change Canada (GNWT and Environment and Climate Change Canada, 2006). The 2008 Plan was updated in 2017 to reflect the monitoring program associated with Extended Care and Maintenance.

What was monitored in 2017?

In 2017, the monitoring program involved the following components:

• Meteorological monitoring – Hourly measurements of wind speed, wind direction, solar radiation, temperature, relative humidity, and rainfall were collected from instruments mounted on a 10 metre (m) tower (Hill Station) and a 3 m tripod (Lake Station).

• Particulate monitoring – Continuous monitoring of particulate matter nominally less than or equal to 2.5 micrometres (µm) aerodynamic diameter (PM2.5) continued until October 2017 when the monitoring stations were disabled for the Winter months (October to March).

Snap Lake Mine - iii - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

• Passive gas monitoring – Passive gas sampling began in January and continued through December; monthly samples were collected for nitrogen dioxide (NO2) and sulphur dioxide (SO2).

What were the Results of the 2017 Meteorological and Air Quality Monitoring Program?

The results of the 2017 monitoring program were:

• Meteorological monitoring – 2017 quarterly wind patterns were similar to 2016, other than a secondary predominance of winds from the west and northwest (De Beers, 2017). Monthly air temperature averages and relative humidity measured at Snap Lake were consistent with patterns and ranges measured in Yellowknife. Annual peak solar radiation occurred in June, consistent with previous years (2006, 2007, 2010, 2012, 2014 and 2016) when the annual peak also occurred in June. The total annual rainfall recorded at the Hill Station in 2017 was 92.46 millimetres (mm), which is lower than the Yellowknife total for 2017 (156.1 mm) and much lower than the Yellowknife long-term (1981 to 2010) annual rainfall average of 170.8 mm (Environment and Climate Change Canada, 2015).

• Passive Monitoring – The passive monitoring of SO2 and NO2 in 2017 indicated concentrations well below the applicable criteria. The annual average SO2 concentration is 0.12 micrograms per cubic metre (µg/m3), which is a decrease of 0.02 µg/m3 from 2016 and below the Northwest Territories (NWT) Ambient Air Quality Standards (AAQS) of 30 µg/m3 (GNWT, 2014a). The annual average NO2 concentration is 0.31 µg/m3, a decrease of 0.21 µg/m3 from 2016 and is still below the NWT AAQS of 60 µg/m3 (GNWT, 2014a).

• Particulate Monitoring – The Dichot Partisols that measured PM10 and PM2.5

located at the airstrip and explosives emulsion plant were decommissioned in July 2014 and replaced with 5030 SHARP PM2.5 monitors in November 2014. Four exceedances of the NWT AAQS 24-hour standard for PM2.5 were recorded for PM2.5

at the airstrip station. The annual average for PM2.5 was 6.01 µg/m3, an increase of 0.70 µg/m3 from 2016.

• Snap Lake Mine Emissions – Fuel consumption was approximately 5,864 cubic metres (m3) of diesel with a maximum sulphur content of 15 parts per million by weight. The space heating furnaces used a mixture of diesel (40%) and waste oil (60%) for fuel, burning a total of 30.6 m3 of waste oil in 2017. Fuel consumption in 2017 was lower than the amount used in 2016, and monthly tonnage of waste burned in 2017 was overall less than the tonnage burned in 2016. Emission rates in 2017 were lower than those reported in 2016 and also remained below the emission rates predicted in the 2007 Air Modelling Update (De Beers, 2007).

Snap Lake Mine - iv - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

TABLE OF CONTENTS

1 INTRODUCTION .............................................................................................................................. 1 1.1 BACKGROUND ............................................................................................................... 1 1.2 LEGISLATION, REGULATORY AND POLICY REQUIREMENTS ....................................... 3 1.3 SCOPE ............................................................................................................................ 3 1.4 OBJECTIVES.................................................................................................................... 4 1.5 METHODOLOGY AND APPROACH ................................................................................. 5

2 METEOROLOGICAL MONITORING ............................................................................................... 8 2.1 OBJECTIVE ...................................................................................................................... 8 2.2 MONITORING STATION LOCATIONS .............................................................................. 8 2.3 MONITORING METHODS ............................................................................................. 13

Monitoring Frequency .................................................................................. 13 Monitoring Parameters ................................................................................ 14

2.4 TEMPERATURE ............................................................................................................. 14 Hill Station Temperature Results ................................................................ 14 Lake Station Temperature Results ............................................................. 14 Discussion .................................................................................................... 17

2.5 WIND SPEED AND WIND DIRECTION .......................................................................... 17 Hill Station Wind Speed and Wind Direction Results ................................ 17 Lake Station Wind Speed and Wind Direction Results .............................. 18 Discussion .................................................................................................... 22

2.6 RELATIVE HUMIDITY .................................................................................................... 23 Hill Station Relative Humidity Results ........................................................ 23 Lake Station Relative Humidity Results ..................................................... 23 Discussion .................................................................................................... 26

2.7 SOLAR RADIATION ....................................................................................................... 26 Hill Station Solar Radiation Results ............................................................ 26 Lake Station Net Solar Radiation Results .................................................. 27 Discussion .................................................................................................... 28

2.8 PRECIPITATION ............................................................................................................ 28 Hill Station Precipitation Results ................................................................ 28 Lake Station Precipitation Results .............................................................. 29 Discussion .................................................................................................... 29

3 AIR QUALITY MONITORING ....................................................................................................... 31 INTRODUCTION ............................................................................................ 31

3.2 ESTABLISHING THE ACTION LEVEL BASIS ................................................................. 33 3.3 PASSIVE SULPHUR DIOXIDE AND NITROGEN DIOXIDE MONITORING ...................... 33

Monitoring Station Locations ...................................................................... 33 Monitoring Methods ..................................................................................... 33 Monitoring Frequency .................................................................................. 34 Data Analysis ................................................................................................ 34

3.4 TOTAL SUSPENDED PARTICLE, PM10 AND PM2.5 MONITORING ............................ 35 Monitoring Station Locations ...................................................................... 36 Monitoring Methods ..................................................................................... 37 Monitoring Frequency .................................................................................. 38

Snap Lake Mine - v - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

Data Analysis ................................................................................................ 38 Total Suspended Particulate Monitoring Results ...................................... 39 PM10 Monitoring Results ............................................................................. 39 PM2.5 Monitoring Results ............................................................................. 39 Discussion .................................................................................................... 44

4 SUMMARY OF 2017 EMISSIONS .............................................................................................. 45 4.1 INTRODUCTION ............................................................................................................ 45 4.2 EMISSION ESTIMATES ................................................................................................. 45

Types of Emissions ...................................................................................... 45 4.3 FUEL USE AND WASTE INCINERATION SUMMARY .................................................... 46

Incinerator Stack Testing Results ............................................................... 49 4.4 EMISSIONS MITIGATION STRATEGIES ........................................................................ 50 4.5 FACILITY EMISSIONS ................................................................................................... 50

Methods ........................................................................................................ 50 Emission Calculation Results ...................................................................... 51

4.6 GREENHOUSE GAS EMISSIONS .................................................................................. 55

5 CONCLUSIONS ............................................................................................................................. 56

6 REFERENCES ............................................................................................................................... 58

LIST OF FIGURES

Figure 1 Location of the Snap Lake Mine, NT .................................................................... 2 Figure 2 Air Quality and Meteorological Monitoring Stations ............................................ 9 Figure 3 Hill Meteorological Monitoring Station ............................................................... 11 Figure 4 Lake Hydro-Meteorological Monitoring Station ................................................. 13 Figure 5 2017 Hill Station Temperature Summary .......................................................... 15 Figure 6 2017 Lake Station Temperature Summary ....................................................... 16 Figure 7 2017 Hill Station Annual Wind Speed and Wind Direction Summary .............. 19 Figure 8 2017 Hill Station Quarterly Wind Speed and Wind Direction Summary .......... 20 Figure 9 2017 Lake Station Annual Wind Speed and Wind Direction Summary ........... 21 Figure 10 2017 Lake Station Quarterly Wind Speed and Wind Direction Summary

.............................................................................................................................. 22 Figure 11 2017 Hill Station Relative Humidity Summary .................................................. 24 Figure 12 2017 Lake Station Relative Humidity Summary ............................................... 25 Figure 13 2017 Hill Station Solar Radiation Summary ...................................................... 27 Figure 14 2017 Lake Station Solar Radiation Summary ................................................... 28 Figure 15 2017 Hill Station Rainfall Summary ................................................................... 30 Figure 16 Annual Average Sulphur Dioxide Concentrations .............................................. 34 Figure 17 Annual Ambient Nitrogen Dioxide Concentrations ............................................ 35 Figure 18 2017 PM2.5 Concentrations at 5030 SHARP PM001 Station .......................... 41 Figure 19 2017 PM2.5 Concentrations at 5030 SHARP PM002 Station .......................... 42 Figure 20 Action Levels for Annual Ambient PM2.5 Concentrations ................................... 43

Snap Lake Mine - vi - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

LIST OF TABLES

Table 1 Relevant Ambient Air Quality Criteria ................................................................... 7 Table 2 Hill Meteorological Monitoring Station Components ......................................... 10 Table 3 Lake Hydro-Meteorological Monitoring Station Components ........................... 12 Table 4 Criteria Used to Trigger Action Levels ................................................................. 32 Table 5 Snap Lake PM2.5 Concentrations ........................................................................ 40 Table 6 Canada-wide Standards for Municipal Waste Incineration Emissions ............. 46 Table 7 Diesel Fuel Consumption Comparisons ............................................................. 47 Table 8 2017 Monthly Fuel Usage from Important Combustion Sources ..................... 48 Table 9 2017 Monthly Waste Tonnage Burned .............................................................. 49 Table 10 Emission Factors ................................................................................................. 52 Table 11 2017 Estimated Emission Rates ........................................................................ 52 Table 12 Estimated Emission Rates Comparisons, 2006 to 2017 ................................. 53 Table 13 2016 Snap Lake Greenhouse Gas Emissions ................................................... 55 Table 14 Annual Snap Lake Greenhouse Gas Emission Comparisons, 2006 to

2017 ..................................................................................................................... 55

Snap Lake Mine - vii - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

LIST OF ABBREVIATIONS

Term Definition

5030 SHARP Thermo Scientific 5030 Synchronized Hybrid Ambient Real-time Particulate (SHARP) Monitor

AAQS Ambient Air Quality Standards

AQEMMP Air Quality and Emissions Management and Monitoring Plan

AQMP Air Quality Monitoring Program

ARKTIS ARKTIS Solutions Inc.

BC British Columbia

CCME Canadian Council of Ministers of the Environment

CH4 Methane

CO2 carbon dioxide

CO2e carbon dioxide equivalent

De Beers De Beers Canada Inc.

DL detection limit

Dichot Partisol dichotomous partisol sampler

e.g. for example

EAR Environmental Assessment Report

EMP Emissions Management Plan

EMS Environmental Management System

ENR Environment and Natural Resources

GHG greenhouse gas

GNWT Government of the Northwest Territories

Golder Golder Associates Ltd.

Hill Station Hill Meteorological Monitoring Station

I-TEQ International Toxic Equivalents

Lake Station Lake Hydro-meteorological Monitoring Station

Mine Snap Lake Mine

MVEIRB Mackenzie Valley Environmental Impact Review Board

N2O nitrous oxide

NAAQO National Ambient Air Quality Objectives

NAD North American Datum

NAPS National Air Pollution Surveillance

NO2 nitrogen dioxide

NOx oxides of nitrogen

NWT Northwest Territories

O2 Oxygen

Partisol Partisol Sampler (A particulate monitoring unit)

PM particulate matter

PM10 particulate matter nominally less than or equal to 10 micrometres (µm) aerodynamic diameter

Snap Lake Mine - viii - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

Term Definition

PM2.5 particulate matter nominally less than or equal to 2.5 µm aerodynamic diameter

QA/QC quality assurance/quality control

SNP Surveillance Network Program

SO2 sulphur dioxide

TSP Total Suspended Particulate

UTM Universal Transverse Mercator

UNITS OF MEASURE

Term Definition

% Percent

º Degrees

°C degrees Celsius

µm micrometer

µg/m³ micrograms per cubic metre

km kilometer

km/h kilometres per hour

kt kiloton

kt/yr kilotonnes per year

kW/m2 kilowatts per square metre

L Litre

L/yr litres per year

m Metre

m3 cubic metre

mg Milligram

mm millimeter

pg I-TEQ/Rm³ picograms per international toxicity equivalents per reference cubic metre

T Tonne

t/d tonnes per day

W/m2 watts per square metre

Snap Lake Mine - 1 - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

1 INTRODUCTION

1.1 BACKGROUND

De Beers Canada Inc. (De Beers) owns and operates the Snap Lake Mine (Mine), a diamond mine located approximately 220 kilometres (km) northeast of Yellowknife, Northwest Territories. The Mine is 30 km south of MacKay Lake and 100 km south of Lac de Gras (Figure 1). Final regulatory approvals for construction and operation of the Mine were granted in May 2004 and construction began in April 2005. Operation of the Mine commenced in 2007. On December 4, 2015, De Beers announced that it would be suspending operations at Snap Lake Mine, and that the Mine would be placed under “care and maintenance”. An Extended Care and Maintenance Plan was submitted to the MVLWB in April 2016 and approved in June 2016. The scope of activities to be undertaken during De Beers’ suspension phase, as well as the ongoing activities will maintain compliance with De Beers’ Water License MV2011L2-0004 and Land Use Permits MV2010D0053 and MV2014D0010. In December 2017 De Beers announced that the Mine will begin preparations for final closure.

The Mine includes the development of underground workings, a processed kimberlite storage facility (the North Pile), Mine facilities and accommodations, an airstrip, water treatment facilities, fuel and ammonium nitrate storage facilities, and a winter access road spur off the Tibbitt-to-Contwoyto winter road that is constructed each winter. De Beers has conducted ambient air quality and meteorological monitoring at the Mine since 1998 when the Advanced Exploration Program began. The programs reflect a commitment by De Beers to identify and mitigate changes to air quality during planning, construction, and operation of the Mine (De Beers, 2002a).

This report provides the results of the air quality and meteorological monitoring programs that were active at the Mine during 2017. It fulfills the annual reporting requirements outlined in the Air Quality and Emissions Management and Monitoring Plan (AQEMMP) (De Beers, 2017).


Figure 1 Location of the Snap Lake Mine, NT


1.2 LEGISLATION, REGULATORY AND POLICY REQUIREMENTS

An Environmental Assessment Report (EAR) for the Mine (De Beers, 2002a) was completed and submitted to the Mackenzie Valley Environmental Impact Review Board (MVEIRB) in February 2002. The MVEIRB in turn completed a review and recommended that the Mine proceed, subject to the implementation of measures to mitigate environmental impacts (MVEIRB, 2003). The MVEIRB report and recommendation were submitted to the Minister of Indian and Northern Affairs Canada in July 2003 and received ministerial approval in October 2003. De Beers received the necessary Water Licence (MV2001L2-0002), Land Use Permit, Land Lease and Environmental Agreement in May 2004 to begin construction and operation of the Mine. De Beers renewed Land Use Permit MV2010D0053 in February 2011 and obtained Land Use Permit MV2014D0010 in June 2014 for fuel storage. De Beers applied for amendments to the Water Licence (MV2011L2-0004) in December 2013 and received approval in September 2015.

De Beers must meet the following requirements regarding air quality, meteorological monitoring, and emissions monitoring:

develop an Air Quality Monitoring Program (AQMP), as outlined in Article VII, Section 7.2 Item a of the Environmental Agreement;

develop an Emissions Management Plan (EMP), as outlined in Article VI, Section 6.3 Items d and e and Article VII, Section 7.2 Item a) of the Environment Agreement; and,

meet the meteorological monitoring requirements specified in the General Conditions (Part B) and the Surveillance Network Program section of the Water Licence (MV2011L2-0004).

Any updates to the monitoring programs will be evaluated, updated and provided to the appropriate stakeholders to be reflective of the activities during Extended Care and Maintenance. The AQEMMP for the post closure phase of the Mine may undergo changes to support the final plan. As such, AQEMMP may be updated as a component of the final closure plan. At that time, any changes to the monitoring programs will be presented in the annual Air Quality Meteorological Monitoring and Emissions Report.

1.3 SCOPE

An initial draft of the AQMP was prepared in September 2003 and was updated in September 2005 based on feedback from the Government of the Northwest Territories (GNWT) and Environment Canada (now titled Environment and Climate Change Canada). A draft of the EMP was submitted to the Snap Lake Environmental Monitoring Agency, GNWT and Environment Canada February 2006. Upon receipt of feedback on this draft (GNWT and Environment Canada, 2006), the AQMP and EMP were harmonized into one document, the AQEMMP, not


only to demonstrate the links between the two monitoring programs but also because the data from the two programs were to be presented together each year in the annual report. The AQEMMP was submitted for review October 2007.

De Beers and Environment and Natural Resources (ENR), met on March 6, 2008, to discuss the harmonized AQEMMP and comments made by ENR in February 2008. Subsequently, the AQEMMP was finalized (De Beers, 2008) to reflect the comments made by ENR in the February 2008 letter and during the March 2008 meeting, as well as comments made by the Snap Lake Environmental Monitoring Agency in a letter submitted to De Beers January 2008.

The overall purpose of this integrated AQEMMP is to provide an overview of the activities included in the air quality monitoring and emissions management plans, and also to provide a template for the annual monitoring reports. The AQEMMP is a “living” document that may need to be adapted as the Mine itself evolves, consistent with the Mine’s Adaptive Management Plan (De Beers, 2004).

An important component of the AQEMMP is the requirement for a comparison of annual monitoring data to emission estimates and dispersion modelling predictions presented in the EAR (De Beers, 2002a). An Air Modelling Update was completed in 2007 (De Beers, 2007). In this document, the 2007 Air Modelling Update is referred to as a basis for comparison with monitoring data.

In December 2014, revised Action Level criteria were adopted, as those outlined in the AQEMMP were deemed too sensitive and overly conservative (Golder, 2014). These revised Action Levels were previously applied to concentrations in the 2014 Air Quality Report (De Beers, 2015), and apply to concentrations measured in 2015, 2016, and 2017. The AQEMMP (De Beers, 2017) was updated in 2017 to reflect the Extended Care and Maintenance phase of the Mine.

1.4 OBJECTIVES

This document has been developed to address the following objectives:

demonstrate compliance with applicable Federal and Territorial ambient air quality standards (AAQS);

track trends in ambient air quality and emissions; provide information required for the Environmental Management System (EMS) (De

Beers, 2002b) to protect air quality; verify the impact predictions made in the 2007 Air Modelling Update (De Beers, 2007); outline response plans to respond to increasing trends, occurrences above the air

quality criteria or occurrences above emission estimates, and dispersion modelling predictions presented in the 2007 Air Modelling Update (De Beers, 2007);


provide data that can make a meaningful contribution to a regional cumulative effects monitoring data bank;

document fuel use as it relates to air quality management; and, facilitate data gathering to develop an approach for emissions mitigation, including the

fugitive dust abatement program.

To achieve these objectives, Sections 2 and 3 of this report concentrate on the following three main components:

on-site meteorological monitoring; ambient monitoring of Total Suspended Particulate (TSP) and fine particulate matter

(PM) with aerodynamic diameters less than or equal to 2.5 μm (PM2.5); and, passive monitoring of sulphur dioxide (SO2 and nitrogen dioxide (NO2)

Section 4 focuses on the following three components:

emissions estimates; fuel use summary; and, emissions mitigation strategies, including the fugitive dust abatement program.

1.5 METHODOLOGY AND APPROACH

De Beers has conducted ambient air quality and meteorological monitoring at the Mine site since 1998, when the Advanced Exploration Program began. De Beers understands the need for adaptive management of the monitoring programs and acknowledges that the monitoring sites may change as the Mine evolves. However, every effort will be made to maintain consistency in the monitoring locations, as this is an important consideration in conducting trend analysis.

Monitoring activities occur both on-site and off-site. On-site monitoring is defined as monitoring that occurs within the active Mine area; “off-site” monitoring occurs outside of the active Mine area (Section 2).

The focus of the AQEMMP is off-site monitoring for consistency with the applicable AAQS, which are based on off-site concentrations measured at or beyond the facility boundary. This off-site monitoring provides an indication of the ambient concentrations of air emissions to which humans, or other components of the receiving environment, may be exposed. The effectiveness of the AQEMMP is dependent, in part, on selecting appropriate criteria against which Mine emissions and the resulting ambient air concentrations should be compared. Currently no provision for air quality is included in permits for mines in NWT, and there is no requirement to monitor for compliance within permit limits. In lieu of air quality permit requirements, the Mine is required to comply with the relevant NWT AAQS for TSP, PM2.5 (24-


hour and annual), NO2 and SO2 (1-hour, 24-hour and annual) (GNWT, 2014a). Table 1 presents the relevant air quality criteria.

In addition to demonstrating that Mine emissions and ground-level concentrations are consistent with the NWT AAQS and other applicable air quality criteria provided in Table 1, it is De Beers’ intent to manage emissions and ground-level concentrations in keeping with the principles of “Continuous Improvement” and “Keeping Clean Areas Clean”, as described in the Canada-Wide Standards for Particulate Matter and Ozone (CCME, 2000a).

De Beers has incorporated design features that demonstrate their commitment to “Keeping Clean Areas Clean” and “Continuous Improvement”. These include, but are not limited to, the following:

selection of highly-efficient combustion equipment; underground and wet primary ore crushing; conveyor-based, covered ore transport systems; short haul route to the North Pile; investigation of alternate energy sources to offset diesel combustion; incineration facilities and waste segregation policies; worker education; on-site recycling programs; and, development of management plans to guide actions and documentation needs around

air quality.

Implementation of these policies and practices demonstrates De Beers’ ongoing commitment to reducing emissions through the use of the best available, economically feasible technology and systems.


Table 1 Relevant Ambient Air Quality Criteria

Parameter NWT Standards(a)

Canada-Wide Standards(b)

Canadian Ambient Air Quality Standards(c)

Other Criteria 2015 2020

SO2 (µg/m3)

1-Hour 450 - - - 450(e)

24-Hour 150 - - - 125(e)

Monthly - - - - 30(e)

Annual 30 - - - 20(e)

NO2 (µg/m3)

1-Hour 400 - - - 300(e)

24-Hour 200 - - - -

Annual 60 - - - 45(e)

TSP (µg/m3)

24-Hour 120 - - - 100(e)

Annual(d) 60 - - - 60(e)

PM10 (µg/m3)

24-Hour - - - - 50(f)

PM2.5 (µg/m3)

24-Hour 28(g) 30 28 27 25(f)

Annual 10 - 10 8.8 8(f)

a) Source: GNWT (GNWT, 2014a). b) Source: CCME (CCME, 2000a). c) Source: Environnent and Climate Change Canada (Environment and Climate Change Canada, 2013). d) As a geometric mean. e) Source: Government of Alberta (AESRD, 2013). f) Source: Government of British Columbia (Government of British Columbia, 2016). g) The NWT Ambient Air Quality Standards for PM2.5 changed from 30 µg/m3 to 28 µg/m in 2014. μg/m3 = micrograms per cubic metres; SO2 = sulphur dioxide; NO2 = nitrogen dioxide; TSP = Total Suspended Particulate; PM10 = particulate matter nominally less than or equal to 10 micrometres aerodynamic diameter; PM2.5 = particulate matter nominally less than or equal to 2.5 micrometres aerodynamic diameter; NWT = Northwest Territories; — = not applicable.


2 METEOROLOGICAL MONITORING

2.1 OBJECTIVE

Meteorological data were measured at Snap Lake during 2017 to contribute to the maintenance of an accurate record of weather conditions at the site. The data may also be used to support future air quality dispersion modelling. Precipitation data are also used in hydrological studies.

As indicated in the 2006 annual report (De Beers, 2006a), De Beers installed a hydro-meteorological monitoring station to provide data specifically for the calculation of lake evaporation. This station is located northeast of the tank farm and collects meteorological data from the lake-side including total precipitation (rain and snow).

2.2 MONITORING STATION LOCATIONS

The hill meteorological monitoring station (Hill Station) is located on an elevated point of land west of the water management pond located at Universal Transverse Mercator (UTM) 506 052E, 7 052 492N NAD (North American Datum) 83 (Zone 12N). The Hill Station is shown in Figure 2, which also displays the locations of the passive monitoring and particulate monitoring sites. Rainfall, temperature, wind, relative humidity, and solar radiation data were collected at the Hill Station in 2017. Data were collected from instruments mounted on a 10 metre (m) tower. Table 2 provides details of each of the sensors installed at the Hill Station to collect meteorological data. Summaries of monitoring results for each parameter are provided in this section. Figure 3 is a photograph of the Hill Station with a view beyond to the north.

The lake hydro-meteorological monitoring station (Lake Station) is located near the freshwater intake at UTM 506 484E, 7 053 277N NAD 83 (Zone 12N). Temperature, wind, relative humidity, and net solar radiation data were collected at the Lake Station in 2017. Low sensor service factors (operational uptime) in the following sections are due to data logger errors and do not necessarily indicate sensor malfunctioning. From the beginning to the end of the year, the snow and rainfall sensor was not functional. All snow or rainfall data was recorded as zero and therefore was not included in this report. Table 3 provides details of each of the sensors installed at the Lake Station that collect meteorological data. Summaries of monitoring results for each parameter are provided in this section. Figure 4 is a photograph of the Lake Station.


Figure 2 Air Quality and Meteorological Monitoring Stations

1) TSP Partisol 1, Dichotomous PM10/PM2.5 Partisol 1 (pre-July 2014), 5030 SHARP PM2.5 Monitor PM001 (November 2014 onwards), Dust Fall Sampling Location DF011, South Airstrip Passive Gas and Dust Fall Monitoring Site (PS001, PS001A, DF011). 2) TSP Partisol 2, Dichotomous PM10/PM2.5 Partisol 2 (pre-July 2014), 5030 SHARP PM2.5 Monitor PM002 (November 2014 onwards), Ammonium Nitrate Fuel Oil Area (Explosives Emulsion Plant) Passive Gas and Dust Fall Monitoring Site (PS002, DF012). 3) West Shore Snap Lake Passive Gas and Dust Fall Monitoring Site (PS006, DF006). 4) North Shore Snap Lake Passive Gas and Dust Fall Monitoring Site (PS007, DF007). 5) TSP Partisol 3, Wetlands Passive Gas and Dust Fall Monitoring Site (PS008, DF008). 6) Tank Passive Gas and Dust Fall Monitoring Site (PS009, DF009). 7) West Airstrip Passive Gas and Dust Fall Monitoring Site (PS013, DF013). 8) Hill Meteorological Monitoring Station. 9) Lake Hydro-Meteorological Monitoring Station.


Table 2 Hill Meteorological Monitoring Station Components

Parameter Instrumentation

Temperature Temperature sensor is housed in a radiation shield that is mounted on the tower at approximately 2 m above ground level

Air temperature -55 °C to +50°C Campbell Scientific HMP45C212

Winds Anemometer is located 10 m above the ground (avoids some of the effects of surface friction consistent with many other sites in North America)

Wind speed in kilometres per hour [km/h] R.M. Young 05103 Wind Monitor, mounted at a height of 10 m

Wind direction degrees [°] R.M. Young 05103 Wind Monitor

Standard deviation of wind direction degrees [°] R.M. Young 05103 Wind Monitor (calculated internally in the datalogger using the Yamartino algorithm)

Solar Radiation Device mounted at 2.5 m on the meteorological station tower

Incoming solar radiation (kW/m²) Licor LI 200S Silicon Pyranometer

Precipitation Device mounted at 2.5 m on the meteorological station tower

Rainfall (mm) Texas Electronics: TE525 WS Tipping Bucket Rain Gauge

Relative Humidity Relative humidity sensor housed in a radiation shield mounted at approximately 2 m above the ground at the meteorological station

Relative humidity (%) Campbell Scientific HMP45C212

Data Storage and Retrieval

Datalogger Campbell Scientific CR1000 (Cold Spec)

Power supply Solar panel and battery back-up

Instrument mounting Campbell Scientific UT30 tower (10 m high)

°C = degrees Celsius; m= metre, ° = degrees; kW/m2 = kilowatts per square metre; mm = millimetre; % = percent.


Figure 3 Hill Meteorological Monitoring Station


Table 3 Lake Hydro-Meteorological Monitoring Station Components

Parameter Instrumentation

Temperature Four temperature sensors are installed at the station. Two are model 107L installed on the lake bed at nominally 1 and 2 m depths. A third 107L is mounted in a radiation shield at nominally 2 m above water surface. The fourth temperature sensor is a component of the combination Campbell Scientific model HMP45C212 temperature/relative humidity sensor. It is mounted in a radiation shield at nominally 1 m above the water surface.

Wind Anemometer is located at 2.5 m above the ground (avoids some of the effects of surface friction consistent with many other sites in North America)

Wind speed (km/h) R.M. Young 05103 Wind Monitor, mounted at a height of 2.5 m above the ground

Wind direction degrees [°] R.M. Young 05103 Wind Monitor

Standard deviation of wind direction degrees [°] R.M. Young 05103 Wind Monitor (calculated internally in the datalogger using the Yamartino algorithm)

Solar Radiation Device mounted at 2.5 m above the water surface

Net solar radiation in kilowatts per square metre [kW/m²]

Kipp & Zonen NRLITE

Precipitation Total precipitation sensor mounted at 2 m above the ground surface

Total precipitation (mm) Yankee Environmental Systems TPS3100

Relative Humidity Relative humidity sensor housed in a radiation shield mounted at approximately 1 m above the water

Relative humidity (%) Campbell Scientific model HMP45C212 temperature/relative humidity sensor

Water level Keller 500C water bourne pressure transducer

Data Storage and Retrieval

Datalogger Campbell Scientific CR1000 (Cold Spec)

Power supply Solar panel and battery back-up

Instrument mounting Campbell Scientific CM10 three metre tripod

m = metre; km/h = kilometre per hour; mm = millimetre; % = percent; ° = degrees.


Figure 4 Lake Hydro-Meteorological Monitoring Station

2.3 MONITORING METHODS

Meteorological monitoring is conducted using a Campbell Scientific-based system. For the Hill Station, sensors are mounted on a 10 m tower while the Lake Station sensors are mounted on a 3 m tripod. Both stations are consistent with current accepted practice in Canada. The stations operate independently using a combination battery/solar panel power supply. A radio link permits communications between the Hill Station and the on-site De Beers’ environmental technician’s office.

Monitoring Frequency

Meteorological monitoring was conducted year-round throughout 2017. Meteorological data were measured continuously and recorded hourly. From January to December, 2017 the Lake Station snow and rainfall sensor was not operating, and data was recorded as zero. The data were downloaded by De Beers’ site staff.


Monitoring Parameters

The Hill Station tower system continuously measured the following meteorological parameters:

wind speed at 10 m above the ground; wind direction at 10 m above the ground; temperature at 2 m above the ground; relative humidity at 2 m above the ground; solar radiation at 2.5 m above the ground; and, rainfall at 2 m above the ground.

The Lake Station tower system continuously measured the following meteorological parameters:

wind speed at 2.5 m above the ground; wind direction at 2.5 m above the ground; temperature at 1 and 2 m above the ground, and 1 and 2 m below the water; relative humidity at 1 m above the water; solar radiation at 2.5 m above the water; and, precipitation at 2 m above the ground.

2.4 TEMPERATURE

Hill Station Temperature Results

The Hill Station hourly temperature values were measured for the entire year, with a data recovery rate of 68.5 percent (%) in 2017. A summary of temperature data at Snap Lake is presented in Figure 5. Monthly mean temperatures ranged from -27.7 degrees Celsius (°C) in December to +17.6°C in August. The annual average temperature at Snap Lake in 2017 was -6.9°C, which was 0.3°C warmer than in 2016 (-7.2°C) and 0.7°C warmer than the 2004 to 2017 average (-7.5°C). The 1981 to 2010 long-term data for Yellowknife are also provided for comparison in Figure 5 (Environment and Climate Change Canada, 2017).

Lake Station Temperature Results

The Lake Station hourly temperature values were measured for the entire year, with a data recovery rate of 73.6% in 2017. A summary of temperature data at Snap Lake is presented in Figure 6. Monthly mean temperatures ranged from -25.2°C in February to +16.7°C in August. The annual average temperature at Snap Lake in 2016 was -7.4°C, which is cooler than Hill Station but 1.1°C warmer than in 2016 (-8.5°C). The 1981 to 2010 long-term data for Yellowknife are also provided for comparison in Figure 6 (Environment and Climate Change Canada, 2017).


Figure 5 2017 Hill Station Temperature Summary

Notes: The monthly averages were calculated based on available data. No data was available for the following times: January 4 to January 7, January 10, January 18 to January 22, January 25 to January 30, May 27 to June 24, August 20 to September 1, October 14 to October 28, November 19 to November 29, November 30 to November 2, December 3 to December 31 Yellowknife data from Environment and Climate Change Canada (Environment and Climate Change Canada, 2017). °C = degrees Celsius.

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Figure 6 2017 Lake Station Temperature Summary

Notes: The monthly averages were calculated based on available data. No data was available for the following times: May 9 to 13, May 19 to June 9, June 21 to June 29, July 6 to July 11, August 1 to August 2, August 20 to September 2, September 9 to September 13, October 7 to October 12, October 29 to November 2. Yellowknife data from Environment and Climate Change Canada (Environment and Climate Change Canada, 2017). °C = degrees Celsius.

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Discussion

The average annual temperature of -6.9°C and -7.4°C in 2017 for Snap Lake Hill and Lake Stations was 2.6°C and 4.1°C colder than the annual temperature of -4.3°C for Yellowknife during 1981 to 2010. The Lake Station data for Snap Lake were similar to the Hill Station data. The maximum difference between the stations was in November where the Lake Station was 5.39°C colder than the Hill Station though there were limited temperature readings for both sites recorded in June (156 and 276 hours for the Hill and Lake stations, respectively). The Lake Station’s position, with its temperature sensors over the water, makes this a plausible scenario. The 2017 monthly air temperature averages in Yellowknife showed a similar pattern to both the Hill Station and Lake Station.

2.5 WIND SPEED AND WIND DIRECTION

Hill Station Wind Speed and Wind Direction Results

The Hill Station wind sensor service factor for 2017 was 0.69; a factor of 1 would mean full data recovery for the year. There is a wind sensor data gap present for the following dates: May 27 to June 23, July 8 to July 21, August 20 to August 30, October 29 to November 1, December 1, December 4, December 7 to December 9, December 11 and 12 and December 15 to December 20.

Figure 7 presents a windrose showing frequencies of wind direction and wind speed for 2017. The predominant winds were from the east with secondary winds from the west and west-northwest. Calm conditions occurred 3.1% of the time. Calm conditions refer to wind speeds less than 3.6 kilometres per hour (km/h), or one metre per second.

Figure 8 shows a series of windroses representing the four quarterly records of wind at Snap Lake. The quarterly figure shows January through March, April through June, July through September and October through December 2017 data in separate windroses. The January to March windrose shows that winds were predominantly from the west-northwest direction with a secondary predominance from northwest. During April to June the winds were predominantly from the east-southeast with a secondary predominance from the east. The windrose for the July to September quarter shows a slight predominance from the south. For October to December winds shows a slight predominance from the north.


Lake Station Wind Speed and Wind Direction Results

The Lake Station wind sensor service factor for 2017 was 0.74. Figure 9 presents a windrose showing frequencies of wind direction and wind speed for 2017. There is a wind sensor data gap for the following dates: May 9 to May 12, May 19 to June 8, June 21 to June 28, July 6 to July 11, July 13 to July 15, July 29 and July 30, August 1, August 12 to August 14, August 17, August 20 to August 31, September 5, October 5 to October 10, October 29 to November 1.

Figure 10 shows a series of windroses representing the four quarterly records of wind at Snap Lake. The predominant winds were from the east. Calm conditions occurred 17.1% of the time. The quarterly figure shows January through March, April through June, July through September and October through December 2016 data in separate windroses. The January to March windrose shows that winds were predominantly from the west with a secondary predominance from the east. From April to June, the winds were predominantly from the east direction. The windrose for July to September shows a slight predominance from the west north-west. For October to December winds show a slight predominance from the west with a secondary predominance from north.


Figure 7 2017 Hill Station Annual Wind Speed and Wind Direction Summary

Notes: A data gap is present from May 27 to June 23, July 8 to July 21, August 20 to August 30, October 29 to November 1, December 1, December 4, December 7 to December 9, December 11 and December 12, and December 15 to December 20. km/h = kilometres per hour; % = percent; > = greater than.


Figure 8 2017 Hill Station Quarterly Wind Speed and Wind Direction Summary

Notes: A data gap is present from May 27 to June 23, July 8 to July 21, August 20 to August 30, October 29 to November 1, December 1, December 4, December 7 to December 9, December 11 and December 12, and December 15 to December 20. km/h = kilometres per hour; % = percent; > = greater than.


Figure 9 2017 Lake Station Annual Wind Speed and Wind Direction Summary

Notes: A data gap is present from May 9 to May 12, May 19 to June 8, June 21 to June 28, July 6 to July 11, July 13 to July 15, July 29 and July 30, August 1, August 12 to August 14, August 17, August 20 to August 31, September 5, October 5 to October 10, October 29 to November 1. km/h = kilometres per hour; % = percent; > = greater than.


Figure 10 2017 Lake Station Quarterly Wind Speed and Wind Direction Summary

Notes: A data gap is present from May 9 to May 12, May 19 to June 8, June 21 to June 28, July 6 to July 11, July 13 to July 15, July 29 and July 30, August 1, August 12 to August 14, August 17, August 20 to August 31, September 5, October 5 to October 10, October 29 to November 1. km/h = kilometres per hour; % = percent; > = greater than.

Discussion

The Hill Station annual windrose shows a similar pattern to previous years’ monitoring but with a wind predominance from the east south-east. Hill station also had a high frequency of winds from the west-northwest, northwest, southeast, and east. The Lake Station annual windrose


shows a similar pattern to previous years’ monitoring with a high frequency of winds from the east or east-southeast. The quarterly windroses illustrate a more diverse range in wind direction throughout the year. As in previous years, winds from the east and southeast dominate April through July 2017.

In 2017, the winds measured during January to March were predominantly west-northwest at the Hill Station and predominantly west at Lake Station while in 2016, the winds measured during January to March at the Lake Station were predominantly from the east (De Beers, 2017). In 2017, the winds measured during October to December showed a slight predominance from the north for the Hill Station and west with a secondary predominance from the north at Lake Station, while in 2016 the winds measured during October to December were predominantly south with a secondary predominance from the north-west at Hill Station and predominantly from the east at Lake Station (De Beers, 2017). During October to December 2014 winds were predominantly from the east-southeast with a secondary predominance from the west-northwest, while during this quarter in 2013 they were from predominantly from the west-northwest. These variations can be attributed to the different seasonal weather patterns that occur because annual wind predominance is influenced by the pattern of large scale weather systems that move through the region.

2.6 RELATIVE HUMIDITY

Hill Station Relative Humidity Results

The Hill Station relative humidity values were measured for the entire year; the sensor service factor was 0.69. Average monthly relative humidity values ranged from 49.8% in July to 92.0% in November. Figure 11 presents the mean monthly relative humidity at Snap Lake. Long term (1981 to 2010) data for Yellowknife are also provided for comparison (Environment and Climate Change Canada, 2017).

Lake Station Relative Humidity Results

The Lake Station relative humidity values were measured for the entire year; the sensor service factor was 0.74. Average monthly relative humidity values ranged from 62.5% in May to 96.0% in October. Figure 12 presents the mean monthly relative humidity at Snap Lake. Long term (1981 to 2010) data for Yellowknife are also provided for comparison (Environment and Climate Change Canada, 2017).


Figure 11 2017 Hill Station Relative Humidity Summary

Notes: A data gap is present from January 18 to January 21, January 25 to January 28, May 9, May 11 and May 12, May 19 to June 8, June 21 to June 28, July 6 to July 11, July 13 to July 15, July 29 and 30, August 1, August 12 to August 14, August 17, August 20 to August 31, September 5, October 7 to October 10, October 29 to November 1, and December 24 to December 31. Source for Yellowknife data: Environment and Climate Change Canada (Environment and Climate Change Canada, 2017). % = percent.

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Figure 12 2017 Lake Station Relative Humidity Summary

Notes: A data gap is present from May 9, May 11 and May 12, May 19 to June 8, June 21 to June 28, July 6 to July 11, July 13 to July 15, July 29 and 30, August 1, August 12 to August 14, August 17, August 20 to August 31, September 5, October 7 to October 10, and October 29 to November 1. Source for Yellowknife data: Environment and Climate Change Canada (Environment and Climate Change Canada, 2017). % = percent.

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Discussion

Relative humidity is a measure of the amount of water vapour present in the air at a given temperature and pressure relative to the maximum amount of vapour that could be present at the same temperature and pressure. If the amount of vapour remains constant and the temperature rises, relative humidity will fall.

Long-term relative humidity averages are provided from daily humidity measurements taken at 6:00 a.m. and 3:00 p.m. in Yellowknife (Environment and Climate Change Canada, 2017). Morning humidity readings are typically higher than afternoon readings, due to cooler morning temperatures, which result in the air having less ability to hold water vapour. The data in Figure 11 and Figure 12 show patterns and ranges consistent with those of the Yellowknife data. The fact that the relative humidity data are typically higher on average at Snap Lake than in Yellowknife could be attributed to overall slightly lower ambient temperatures but similar levels of absolute ambient moisture. The data in Figure 11 and Figure 12 have a similar pattern and range between the Hill Station and the Lake Station. The Lake Station ranged from 25.1% higher (June) to 1.8% lower than the Hill Station. The difference in reported humidity between the two stations in June, is influenced by the limited June data recovery (156 and 276 hours of data for the Hill and Lake Stations, respectively).

2.7 SOLAR RADIATION

Hill Station Solar Radiation Results

The Hill Station solar radiation sensor service factor for 2017 was 0.69. Figure 13 presents the monthly solar radiation summary. Values ranged from a monthly average of 10.80 watts per square metre (W/m2) in December to an average of 281.72 W/m2 in June.


Figure 13 2017 Hill Station Solar Radiation Summary

Notes: A data gap is present from January 18 to January 21, January 25 to January 28, May 27 to June 23, July 8 to July 21, August 20 to August 31, October 29 to November 1, December 1, December 4, December 7 to December 9, December 11 and December 12, and December 15 to December 20. W/m2 = watts per square metre.

Lake Station Net Solar Radiation Results

The Lake Station net solar radiation sensor service factor for 2017 was 0.74. Figure 14 presents the monthly net solar radiation summary. Values ranged from a monthly average of --12.49 W/m2 in December to an average of 124.85 W/m2 in June.

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Figure 14 2017 Lake Station Solar Radiation Summary

Notes: A data gap is present for May 9, May 11 and May 12, May 19 to June 8, June 21 to June 28, July 6 to July 11, July 13 to July 15, July 29 and July 30, August 1, August 12 to August 14, August 17, August 20 to August 31, September 5, October 7 to October 10, and October 29 to November 1. W/m2 = watts per square metre.

Discussion

Solar radiation levels measured at the surface are a function of hours of sunlight and sun azimuth angle, as well as a function of local weather conditions including relative humidity, cloud cover, cloud type, and cloud depth. Changes in weather variables may cause the annual peak to fluctuate from year to year. The peak solar radiation occurred in May for 2004, 2005, 2008, 2009, 2011, 2013 and 2015 and in June for 2006, 2007, 2010, 2012, 2014, 2016 and 2017. Total solar radiation (incoming radiation only) at the Hill Station and net solar radiation (incoming less than outgoing radiation) at Lake Station cannot be directly compared.

2.8 PRECIPITATION

Hill Station Precipitation Results

In general, rainfall was collected between April and October when temperatures exceeded 0°C. The Hill Station rainfall sensor was operational 68.5% of the time throughout the year. The highest monthly rainfall was 46.99 millimetres (mm) in July 2017. Figure 15 provides a comparative summary of the monthly rainfall readings for Snap Lake in 2017 versus the monthly rainfall for Yellowknife in 2017 (Environment and Climate Change Canada, 2017) and from 1981 to 2010 (Environment and Climate Change Canada, 2015).

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Lake Station Precipitation Results

The Lake Station snow and rainfall sensor continued to not be operational in 2017. The TPS3100 was disconnected in 2014 because it has not functioned properly despite being repaired in 2013. In 2015, following the installation of a new sensor, data was not collected until August 22, 2015 due to the sensor not operating. The data that was collected in 2015 was compared to precipitation recorded at the Hill Station and local weather observations, and it was determined that the sensor continued to malfunction. Due to the sensor continuing to malfunction, no precipitation data is included for the Lake Station in this report.

Discussion

The total annual rainfall recorded at the Hill Station for Snap Lake in 2017 was 92.46 mm, which is approximately 40.8% lower than the Yellowknife total for 2017 (156.1 mm) and 45.9% lower than the Yellowknife long-term (1981 to 2010) annual rainfall average of 170.8 mm. The monthly rainfall totals at Snap Lake were higher than those for Yellowknife in 2017 in April, May and July. Monthly rainfall totals at Snap Lake were lower than those for Yellowknife in January, February, March, June, August, September, October, November, and December. The lower precipitation totals for Hill Station are partly due to the limited number of rainfall data collected especially for the month of June which recorded 0 mm of rain compared to 109.22 mm in 2016.

The monthly rainfall observed at Yellowknife in 2017 was higher than the corresponding 1981 to 2010 monthly rainfall averages for April and July, lower in January, March, May, August, September, October, November, and December, and the same (no rainfall observations) in February (Figure 15).

The rain gauge at the Hill Station is not shielded, which could contribute to precipitation undercatch. A study by Mekis and Vincent (Mekis and Vincent, 2011) showed that rain gauges that are not equipped with a wind screen can result in an undercatch of up to 20% in the Canadian Arctic. Therefore, actual precipitation at the Mine could be higher than what is currently being measured.

Snap Lake Mine -30- March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1

Figure 15 2017 Hill Station Rainfall Summary

Notes: A data gap is present from May 27 to June 23, July 8 to July 21, August 20 to August 31, October 29 to November 1, December 1, December 4, December 7 to December 9, December 11 and December 12, and December 15 to December 20. W/m2 = watts per square metre

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3 AIR QUALITY MONITORING

3.1 INTRODUCTION

One of the purposes of the AQEMMP is to identify trends in ambient air quality and to use this information to inform management decisions around emissions mitigation (GNWT and Environment and Climate Change Canada, 2006). This type of proactive management requires that a clear and well-documented system be established. This section provides details on how this system operates.

For the system to operate effectively, the following parameters must be clearly defined:

the methods for evaluating trends and identifying when emissions mitigation is necessary;

the monitoring timeframe over which emissions mitigation decisions will be made; and, the Action Levels at which emissions mitigation will be employed.

Each year the annual average concentrations of SO2, NO2, TSP, and PM2.5 are summarized as part of the annual report. PM10 concentrations were also monitored and reported up to July 2014, when the Dichot Partisols were decommissioned. These concentrations are then compared to various percentages of the applicable ambient air quality criteria to assess which Action Level is appropriate. A description of how the Action Levels should be applied to each of the substances emitted by the Mine is provided below.

A systematic approach was taken to develop action levels for each compound based on the 2007 Air Modelling Update predictions (De Beers, 2007), the applicable ambient air quality criteria, and percent change (year to year) in measured concentrations. Revised Action Levels were adopted based on recommendations submitted in December 2014, as the criteria outlined in the AQEMMP were deemed too sensitive and overly conservative (Golder, 2014), and will be applied to concentrations measured in 2015, 2016, and 2017.

The Action Levels for SO2, TSP, PM10, and PM2.5 are as follows:

Action Level I – annual aggregate concentrations are above the 2007 Air Modelling Update prediction (De Beers, 2007) but remain below 50% of the applicable ambient air quality criteria;

Action Level II – annual aggregate concentrations are above the 2007 Air Modelling Update prediction (De Beers, 2007) but remain below 75% of the applicable ambient air quality criteria; and,

Action Level III – annual aggregate concentrations are within 25% of the applicable ambient air quality criteria.


The above action levels are not applicable to NO2, as the NO2 concentrations predicted in the 2007 Air Modelling Update (De Beers, 2007) were elevated relative to the ambient air quality criteria and therefore required more proactive emissions management. The Action Levels for NO2 are as follows:

Action Level I – annual aggregate concentrations are at or below 75% of the applicable ambient air quality criteria;

Action Level II – annual aggregate concentrations are between 75% and 90% of the applicable ambient air quality criteria;

Action Level III – annual aggregate concentrations are within 10% of the applicable ambient air quality criteria.

The management action that will be implemented for each of the Action Levels is as follows:

Action Level I – continue monitoring, no mitigation necessary. Action Level II – internal review and development and implementation of Action Plan. Action Level III – external review and development and implementation of Action Plan.

Table 4 indicates the criteria that will be used to evaluate concentrations of SO2, NO2, PM2.5, PM10, and TSP. If either an internal or external review is necessary, this will likely include a review of ambient monitoring data and emissions to assess whether the elevated concentrations or trend are related to Mine equipment or operations. In this manner, any potential issues can be resolved before the ambient air quality standards are reached, which is the primary benefit of this type of proactive management system.

Table 4 Criteria Used to Trigger Action Levels

Parameter Criteria (µg/m³) Source

Maximum Annual SO2 30 NWT AAQS (GNWT, 2014a)

Maximum Annual NO2 60 NWT AAQS (GNWT, 2014a)

Maximum 24-Hour TSP 120 NWT AAQS (GNWT, 2014a)

Maximum Annual TSP 60 NWT AAQS (GNWT, 2014a)

Maximum 24-Hour PM10 50 Objective in British Columbia (Government of British Columbia, 2016)

Maximum 24-Hour PM2.5 28 NWT AAQS (GNWT, 2014a)

SO2 = sulphur dioxide; NO2 = nitrogen dioxide; TSP = Total Suspended Particulate; PM10 = particulate matter less than 10 microns diameter; PM2.5 = particulate matter less than 2.5 microns diameter; µg/m³= micrograms per cubic metre, GNWT = Government of Northwest Territories, AAQS = Ambient Air Quality Standards.

De Beers intends to transition the site to zero permanent occupancy each year from near freeze-up to just prior to the following freshnet during the Extended Care and Maintenance Phase (De Beers Canada Inc., 2017). To ensure compliance with De Beer’s water licence and Land Use permits, a team will physically visit the site at monthly intervals during this period or as required to collet monitoring samples and conduct inspections (De Beers Canada Inc., 2017).


3.2 ESTABLISHING THE ACTION LEVEL BASIS

Implementation of the ambient air quality response plan began in 2007 and is the basis from which 2017 trends in SO2, NO2, and PM2.5 concentrations are compared. The three air quality components that were examined from 2007 to 2017 were SO2, NO2 and particulate matter.

3.3 PASSIVE SULPHUR DIOXIDE AND NITROGEN DIOXIDE MONITORING

SO2 and NO2 emissions are generated by the combustion of diesel fuel and the incineration of solid waste at the Mine. De Beers monitors these substances on a monthly basis using passive sampling technology.

Monitoring Station Locations

In 2017, passive monitoring was conducted at the Mine at seven separate locations: four off-site locations sited to demonstrate that ambient ground level concentrations are consistent with the criteria; and three on site locations whose data will be used to make informed decisions about occupational health and safety levels. The off-site locations were as follows, and are shown in Figure 2:

at the southeast end of the airstrip, co-located with the 5030 SHARP monitors (Partisol samplers were replaced with 5030 SHARP monitors in November 2014);

south of the emulsion plant, co-located with the 5030 SHARP monitors (Partisol samplers were replaced with 5030 SHARP monitors in November 2014);

at the west end of Snap Lake (distant reference site); and, on the north shore of Snap Lake, adjacent to the Mine.

The on-site locations were:

just west of the tank farm, co-located with TSP Partisol 3; immediately north of the fire hall, just west of the three large fuel storage tanks; and, near the west end of the airstrip.

Monitoring Methods

Passive monitoring has been conducted over the past several years to generate ambient air quality data for SO2 and NO2. Sampling is conducted using “charged” cartridges containing material that is both reactive and selective to the target gases. After approximately 30 days of exposure beneath a rain shelter, the samples are retrieved from the field and sent to the laboratory for analysis. Results are reported in parts per billion and can be nominally compared to the annual ambient air quality criteria for the respective compounds.



Sampling is conducted continuously, year-round with sample cartridges exposed to the environment for approximately 30 days before being sent to the laboratory for analysis.

Data Analysis

Figure 16 compares the 2007 to 2017 SO2 passive monitoring data to 50% of the NWT AAQS for SO2 and the 2007 Air Modelling Update Prediction (De Beers, 2007). Based on the passive data collected in 2017, a response consistent with Action Level I is appropriate as defined in Section 3.1. Action Level I is appropriate because the concentrations remain below 50% of the NWT AAQS. The annual average SO2 concentration is 0.12 micrograms per cubic metre (µg/m3), which is a decrease of 0.02 µg/m3 from 2016 and well below the NWT AAQS of 30 µg/m3. The overall trend that is emerging in the data shows little change year to year.

Figure 16 Annual Average Sulphur Dioxide Concentrations

μg/m3 = micrograms per cubic metres; SO2 = sulphur dioxide; NWT AAQS = Northwest Territories Ambient Air Quality Standard.

Figure 17 compares the 2007 to 2017 NO2 passive monitoring data to 75% of the National Ambient Air Quality Objective, 75% of the NWT AAQS, and the 2007 Air Modelling Update Prediction (De Beers, 2007). Based upon the 12 months of passive NO2 data collected in 2017, a response consistent with Action Level I is appropriate, as defined in Section 3.1. Action

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Level I is appropriate because the 2017 concentrations remain below 75% of the NWT AAQS. The annual average NO2 concentration in 2017 is 0.32 µg/m3, which is a decrease of 0.20 µg/m3 from 2016 and well below the NWT AAQS of 60 µg/m3. The NWT standard for annual NO2 is currently 60 µg/m³ (GNWT, 2014a). Prior to 2011, the National Ambient Air Quality Objective (NAAQO) of 100 µg/m³ (Environment and Climate Change Canada, 2011) was used to compare the measured annual ambient NO2 concentrations.

Figure 17 Annual Ambient Nitrogen Dioxide Concentrations

μg/m3 = micrograms per cubic metres; % = percent; NO2 = nitrogen dioxide; NAAQO = National Ambient Air Quality Objective.

3.4 TOTAL SUSPENDED PARTICLE, PM10 AND PM2.5 MONITORING

Suspended particulate matter (fine dust) emissions are generated by wind erosion of local landscapes, movement of vehicles or equipment, airstrip activities, construction activities, the combustion of diesel fuel and the incineration of solid waste materials.

Current understanding is that those particles small enough to readily enter the lungs and bronchi of the lower respiratory tract are of most concern. These particles are typically PM2.5.

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Because monitoring of PM2.5 is considered to fulfill regulatory requirements, all three TSP stations were subsequently decommissioned by the end of 2015. Therefore, no monitoring for TSP was conducted in 2016 or 2017. The PM2.5 monitoring was carried out in 2017 to address the AQEMMP requirements outlined in Article VI, Section 6.3 (Item e) (ii & iii) of the EAR (De Beers, 2002a):

6.3 (e) DBCMI shall prepare and provide to the Parties and the Monitoring Agency an Air Quality and Emission Management annual report summarizing and analyzing the emissions and ambient monitoring information, including:

ii. Comparisons of ambient air quality and deposition monitoring results to previous years, the predictions of the Environmental Assessment Report dispersion modeling and all applicable federal and territorial ambient air quality criteria, standards, objectives and guidelines.

iii. Analysis of emissions and ambient air quality trends and effectiveness of strategies employed to minimized emissions.

It also fulfills the requirements ascribed to the AQEMMP in Article VI, Section 7.2 Item of the Environmental Agreement for the Mine:

7.2 (a) The Air Quality Monitoring Program shall include but not be limited to:

i. Monitoring total suspended particulate (TSP), PM10 and PM2.5. ii. Monitoring of fugitive dust to determine the effects of dust deposition on the

surrounding environment. iii. Documentation of quality assurance and quality control (QA/QC) procedures used to

ensure valid data collection. iv. Contingency plans to respond to increasing trends or exceedances of air quality

criteria/dispersion modelling predictions.

Monitoring Station Locations

On-site monitoring locations were selected during early construction to provide a conservative management approach to monitoring ambient particulate concentrations. These locations were selected based on areas of maximum particulate predictions produced by the dispersion modelling assessment (De Beers, 2002a). The demonstration of compliance with ambient air quality benchmarks at these locations can be extrapolated to represent compliance at off-site locales.

The locations for both on-site and off-site monitoring stations for the ambient particulate monitoring program are provided in Figure 2. The off-site locations were selected because they provide a representative estimate of particulate concentrations away from high intensity mining activities. The availability of electrical power was also a key consideration for these locations. The TSP Partisol 3 (on site) was specifically added to provide additional information


to De Beers concerning on site particulate levels and to provide information to occupational health and safety planning personnel.

The two Thermo Scientific 5030 SHARP Monitors are each co-located with a TSP Partisol sampler and are located off site, directly adjacent to the facility boundary by the airstrip and explosives emulsion plant. The 5030 SHARP Monitors, which only measure PM2.5, were installed in November 2014 to replace the PM10 and PM2.5 Dichotomous Partisol samplers (Dichot Partisol) at these sites. At the end of 2015, the three TSP Partisols were decommissioned. These locations were identified as areas of potentially higher off-site particulate concentrations by dispersion modelling predictions. These locations are intended to be permanent and should not need to be moved in the future. Permanent locations produce consistent data suitable for comparison purposes over time.

Monitoring Methods

Partisols and Dichot Partisols operate on the principle that a stream of ambient air at a controlled flow rate is drawn through a size-selective inlet and then through a pre-weighed filter for a pre-determined time period. The exposed filter is shipped to a laboratory where it is re-weighed. The TSP, PM10, and PM2.5 concentrations can be determined using the measured volume of air and the weight difference between the pre-weighed and exposed filter.

The TSP Partisols at Snap Lake collect particulate with a nominal aerodynamic diameter of 100 µm or smaller. The collection of TSP provides a good measure of airborne particulate; the 24-hour and annual average concentrations are subject to the GNWT ambient air quality standards of 120 and 60 µg/m³ respectively (GNWT, 2014a).

This type of monitoring is a United States Environmental Protection Agency (USEPA) reference method for quantifying ambient PM10 and PM2.5 concentrations. The collection of PM2.5 is also subject to a standard in the NWT (GNWT, 2014a).

Concentrations calculated for particulate mass measured by the laboratory that were missing a corresponding air sample volume were estimated by using the typical sample volume for TSP and PM2.5 of 24 cubic metres (m3), 2.4 m3, and 21.6 m3 respectively. When the laboratory was not able to detect particulate mass on the filters and in these cases reported a non-detect (less than 0.001 milligrams [mg]), these non-detects were included in the statistics and calculated at half the detection limit (DL = 0.001 mg).

However, prior to decommissioning in July 2014, the PM10 and PM2.5 data collected by the Dichot Partisols is suspect, as some values of PM2.5 were greater than PM10 during the same sampling period, which in reality, is not possible. Nevertheless, these instruments are no longer in operation, as discussed in Section 3.4.1.

The 5030 SHARP is a continuous monitor capable of providing real-time measurements. It operates on the principles of aerosol light scattering (nephelometer) and beta attenuation to


measure ambient particulate matter concentrations. When a particle enters the instrument, it scatters light which is emitted by a beam. The amount of light which is scattered is dependent on the size of the particle. The particle is then deposited onto a glass fibre filter tape, which accumulates mass up to a threshold value. When this value is reached, the tape is advanced so that sampling can be done on a clean portion of the tape. The mass of the sample is measured using beta radiation, as the amount of beta radiation absorbed by a sample is dependent on the mass of a sample. The instrument concurrently measures the volume of the sample, thus allowing the calculation of the ambient concentration.


The monitoring of TSP was carried out according to the National Air Pollution Surveillance (NAPS) schedule. This schedule followed a monitoring cycle where a single 24-hour sample was collected every sixth day. The schedule has been followed at the Mine since April 2000 when the original High Volume monitoring program began. However, due to ongoing technical problems with the TSP Partisols, all three stations were decommissioned by the end of 2015. Monitoring of PM2.5 will continue in order to fulfill the regulatory requirements.

PM2.5 monitoring using the 5030 SHARP began in November 2014 and occurs continuously.

Prior to decommissioning of the TSP Partisols, particulate sampling was conducted year-round. Sampling during extreme winter conditions (-20°C and colder with winds greater than 15 km/h) typically occurs between the months of October and April. A small amount of data loss is expected during the winter as ambient conditions exceed the normal operating range expected for the equipment. Climate controlled shelters installed by De Beers in the spring of 2008 to contain the Partisol sampling equipment have minimized, but not eliminated, data loss.

Sampling in accordance with the NAPS schedule provides consistency between the Snap Lake particulate monitoring stations and stations at other facilities across Canada. In addition, by operating on a six-day cycle, different days are sampled each week, which allows for the monitoring of differing production intensities or other operational variability.

In 2017, a change to the monitoring frequency of the SHARP Monitors (ARKTIS, 2017), located at the emulsion plant and airstrip, was approved by the GNWT and summarized in the updated Air Quality and Emissions Monitoring and Management Plan (De Beers Canada Inc., 2018). In summary, the SHARP Monitors will be operational in the summer (April to September) and not operational in the winter (October to March). This change to monitoring was implemented as of October 2017.

Data Analysis

Particulate matter data from the three monitoring locations were analyzed to identify potential air quality concerns, for example, increasing trends or measured concentrations above the


2007 Air Modelling Update (De Beers, 2007) predictions and applicable ambient air benchmarks.

Analysis of temporal trends and comparisons to applicable ambient air criteria helps to identify consistent patterns in the measured particulate concentrations on an annual basis. The response planning and Action Levels associated with various particulate concentrations relative to the 2007 Air Modelling Update (De Beers, 2007) predictions and applicable ambient air criteria are described in Section 3.1. Managing trends in ambient particulate concentrations on an annual basis is appropriate given the scale of the Mine and the long-term nature of the monitoring program.

In addition to the annual trend analysis, ongoing visual observation at the Mine is intended to assist in quickly identifying any abnormal high-dust events and triggers, and if necessary, remedial actions. The potential cause(s) of such events and the mitigation action available will be evaluated and implemented as appropriate.

Total Suspended Particulate Monitoring Results

All three TSP stations were decommissioned by the end of 2015. Therefore, no new samples were collected in 2017.

PM10 Monitoring Results

Dichot Partisols at the airstrip and explosives emulsion plant sites were decommissioned in July 2014, during which month the occurrence of forest fires in the region (GNWT, 2014b) prevented the measurement of PM. In November 2014, they were replaced with 5030 SHARP PM2.5 monitors, which continuously record PM2.5 data. Thus, no monitoring data for PM10 is available after June 2014.

PM2.5 Monitoring Results

5030 SHARP instruments measured the average daily PM2.5 concentration throughout 2017 with a data recovery rate of 64.1% and 27.6% from the PM001 and PM002 monitors respectively. The PM2.5 monitoring results are provided in Table 5 and Figure 18 and Figure 19.

The maximum recorded daily PM2.5 concentration was 88.8 µg/m³, which was observed on August 12, 2017 at the airstrip site. This occurrence exceeded the 24-hour objective of 28 µg/m3 (GNWT, 2014a). In total, four exceedances of the 24-hour PM2.5 standard were recorded at the airstrip site. No exceedances were recorded at the emulsion plant site. All exceedances occurred between August and September. These concentrations are higher than expected, and it is suspected that there are other factors influencing these anomalous periods of high PM2.5

concentrations and the other high concentrations observed in March, May, and September.


Concentrations in these ranges are not expected to be related to routine mine activities. Sufficient information is not available to definitively conclude the reason for the high values.

Though multiple exceedances of the 24-hour PM2.5 standard were recorded at the airstrip, the time-weighted annual average PM2.5 concentration was 6.01 µg/m³. Action Level I was triggered for PM2.5, as the annual average of 6.01 µg/m³ is below the NWT AAQS (Figure 20). Action Level I indicates that monitoring should continue and no mitigation is necessary. Figure 20 also compares the 2017 PM2.5 data to the 2007 Air Modelling Update prediction (De Beers, 2007).

Table 5 Snap Lake PM2.5 Concentrations

Compound Monitoring Sites

Applicable Guideline (μg/m3)

2007 Air Modelling Update(a)

(De Beers, 2007) (μg/m3) 2017 (μg/m3)

24-Hour Annual Hourly Annual 24-Hour Max

Annual Average

PM2.5

5030 SHARP PM001(b) (c)

28 10 24.3 6.2 88.8(a) 6.7(a)

5030 SHARP PM002(b) (d) 29.3 5.3

a) Excluding the period of sensor malfunction where zero and negative values were recorded as a result of sensor failure. μg/m3 = micrograms per cubic metres; PM2.5= particulate matter less than 2.5 microns diameter; max= maximum. b) 5030 SHARP instruments were installed in November 2014. c) A data gap is present from May 8 to June 6. Data from June 25 to July 1 and August 14 to August 18 were not included as their measurements were believed to be faulty. SHARP PM0001 station does not run for the winter period, and thus no data was collected after October 3. d) A data gap is present from March 4 to March 29 and May 8 to December 31. The SHARP PM002 station required maintenance and was not repaired prior to the winter period when SHARP Monitors are not active.


Figure 18 2017 PM2.5 Concentrations at 5030 SHARP PM001 Station

PM2.5= particulate matter less than 2.5 microns diameter; μg/m3 = micrograms per cubic metre; NWT AAQS = Northwest Territories Ambient Air Quality Standard. Notes: A data gap is present from May 8 to June 6. Data from June 25 to July 1 and August 14 to August 18 were not included as their measurements were believed to be faulty. SHARP PM0001 station does not run for the winter period, and thus no data was collected after October 3.

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Figure 19 2017 PM2.5 Concentrations at 5030 SHARP PM002 Station

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Figure 20 Action Levels for Annual Ambient PM2.5 Concentrations

Notes: Annual site average PM2.5 concentration for 2017 is based on both the PM001 airstrip and PM002 emulsion plant recordings. μg/m³ = micrograms per cubic metre; PM2.5= particulate matter nominally less than or equal to 2.5 microns aerodynamic diameter; NWT AAQS = Northwest Territories Ambient Air Quality Standard.

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Discussion

In 2017, the time-weighted average PM2.5 concentration over the monitoring period was 6.01 µg/m³. It is important to note that this time-weighted average included above normal reading which were suspect to be faulty (but could not be confirmed), as well as, a low data recovery rate for PM002 (SHARP Monitoring station PM002 will be repaired for 2018 data collection). According to the available readings that were not excluded for being suspect as faulty, there were four exceedances recorded above the NWT 24 hour PM2.5 standard (GNWT, 2014a) of 28 µg/m³ at the airstrip site from August to September. An Action Level I response was triggered and subsequently monitoring will continue.

Commented [jv1]: De Beers to confirm.


4 SUMMARY OF 2017 EMISSIONS

4.1 INTRODUCTION

The AQEMMP is used to coordinate the monitoring of emissions from the Mine, which were compared to the 2007 Air Modelling Update (De Beers, 2007). The three main components of the emissions summary and the sections in which they are discussed, are as follows:

emissions estimates (Section 4.2); fuel use summary (Section 4.3); and, emissions mitigation strategies, which include the dust abatement program (Section

4.4).

4.2 EMISSION ESTIMATES

The emissions estimate component of the 2017 Annual Report has the following objectives:

demonstrate De Beers’ commitment to ongoing monitoring of emissions at the Mine site;

provide an overview of the appropriate methods for calculating emissions from the Mine;

compare Mine emissions to those modelled in the 2007 Air Modelling Update (De Beers, 2007); and,

demonstrate De Beers’ commitment to minimizing emissions.

Types of Emissions

4.2.1.1 COMBUSTION EMISSIONS

Combustion is the process of burning fuels of various types, and using the energy released to produce electricity, space or process heating, or to facilitate on-site transportation and incineration. The primary combustion sources at the Mine are:

power generators; mine air heaters; surface fleet; incinerators; and, furnaces.

Substances such as SO2, oxides of nitrogen (NOX), particulates, and greenhouse gases (GHGs) are common combustion by-products from Mine sources. These by-products are the subject of regulatory guidance, which limits the release amounts to protect the receiving environment. Other combustion by products, such as dioxins, furans and mercury may also be released


during on site waste incineration (CCME, 2001). Canada-Wide Standards for dioxins, furans, and mercury (Table 6) apply to municipal waste incineration at new facilities such as the Mine. Meeting the Canada-Wide Standards often requires the use of best available control techniques, such is a waste diversion program.

Table 6 Canada-wide Standards for Municipal Waste Incineration Emissions

Municipal Waste Incineration Compound Emission Limit

Dioxins and Furans(a) 80 picograms of International Toxic Equivalents (I-TEQ) per cubic metre

Mercury(b) 20 micrograms per cubic metre (µg/m3)

a) (CCME, 2001); corrected to 11% of oxygen (O2) content. b) (CCME, 2000b).

4.2.1.2 FUGITIVE EMISSIONS

Fugitive emissions are substances that are released to the atmosphere without passing through a stack, vent, or functionally equivalent opening. Fugitive emissions can occur as a result of the Mine construction and operation activities and are expected to consist primarily of fugitive dust.

Fugitive dust emissions can result from Mine sources through either mechanical or natural processes. Examples of mechanical processes that can generate fugitive dust include crushing, materials handling, vehicle fleet operation, heavy equipment operation, vegetation removal and the take-off and landing of aircraft from the airstrip. The main natural process that generates fugitive dust is wind erosion. The main potential fugitive emission sources at the Mine are:

• the roads and airstrip; and, • the North Pile.

4.3 FUEL USE AND WASTE INCINERATION SUMMARY

Data to date on fuel use and waste incineration are compared to the 2007 Air Modelling Update (De Beers, 2007) predictions in this section. Comparing fuel usage in the 2007 Air Modelling Update (Table 7) (De Beers, 2007) shows that total fuel consumption and therefore emissions at the Mine were well below the levels used to predict ground-level concentrations.

Table 8 reports the monthly fuel usage for the Mine combustion sources, identified in Section 4.2.1 and compares these values to the 2007 Air Modelling Update (De Beers, 2007). The 2017 fuel consumption totals were estimated based on the 2013 to 2015 percentages used per source due to the individual breakdowns not being available, with the exception of the mobile fleet totals which were used.


Table 7 Diesel Fuel Consumption Comparisons

Source

Diesel Consumption Rate (L/yr)

2007 Air Modelling

Update (De Beers,

2007) 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

Power Generators(a) 28,319,000 5,782,945 15,761,482 19,886,852 25,094,725 26,309,858 23,447,183 28,660,205 28,987,455 30,648,122 16,654,907(g) 4,185,166(g)

Mine Heaters and Incinerators 11,318,000 5,376,223 2,585,818 745,100 568,868 631,236 3,264,199 4,840,242 5,363,806 7,977,785(b) 3,468,785g) 867,656(g)

Fleet 7,225,000 6,832,013 2,438,514 3,823,752 3,071,664 3,819,252 4,697,621 3,123,905 2,825,052 4,307,483(c) 744,372 760,618

Furnaces - - - - 159,198 311,780 359,892 487,180(d) 572,038(e) 276,163(f) 262,573(g) 51,039(g)

Total 46,862,000 17,991,181 20,785,814 24,455,704 28,894,456 31,072,126 31,768,895 37,111,532 37,748,351 43,209,553 21,129,556(h) 5,864,479(h)

a) Includes pumps, compressors, welders, and other equipment. b) Includes main and ancillary boilers/heaters. Consumption based on approximate monthly usage outlined in the 2015 Master Dip Sheet and Fuel-Enviro reports. c) Any fuel balance not accounted for in the yearly fuel consumption total is allocated to the fleet. d) Furnaces are mainly using diesel fuel, but the 2013 total includes 60,000 L of waste oil. e) Furnaces are mainly using diesel fuel, but the 2014 total includes 30,000 L of waste oil. f) Furnaces are using a mixture of diesel fuel (40%) and waste oil (60%), but are included in the total. g) Fuel consumption based on the 2013-2015 ratio of fuel usage due to the total fuel usage breakdown being unavailable. h) The yearly total is not a sum of the fuel sources due to an error in rounding. The total presented is the actual 2016 and 2017 reported fuel total. L/yr = litres per year.


Table 8 2017 Monthly Fuel Usage from Important Combustion Sources

Month Power Generation(a)

(m³) Mine Heaters(b)

(m³) Mobile Fleet(c)

(m³) Incineration

(m³) Furnaces(d)

(m³) Total(e)

(m³)

2007 Air Modelling Update (De Beers, 2007)

(m³)

January 1,090 401 73 12 32 1,608 3,905

February 415 134 64 4 12 630 3,905

March 694 238 463 7 21 1,423 3,905

April 300 76 0 3 5 384 3,905

May 288 33 65 3 2 392 3,905

June 224 2 25 3 0 254 3,905

July 176 0 7 2 0 186 3,905

August 180 8 6 4 0 197 3,905

September 151 5 5 3 1 166 3,905

October 170 20 32 3 2 228 3,905

November 136 39 10 2 3 191 3,905

December 146 44 12 2 3 207 3,905

Total 3,971 1,002 762 48 82 5,864(g) 46,862

*Note: Monthly source total fuel consumptions based on the 2013-2015 monthly ratios of fuel usage due to the 2017 total fuel usage breakdown being unavailable with the exception of the mobile fleet totals. a) Includes pumps, compressors, welders, and other equipment. b) Includes main and ancillary boilers/heaters. Consumption based on approximate monthly usage outlined in the 2015 Master Dip Sheet and Fuel-Enviro reports. c) Any fuel balance not accounted for in the yearly fuel consumption total is evenly allocated to the fleet. d) Furnaces are using a mixture of diesel fuel (40%) and waste oil (60%), but are included in the total. e) Actual 2017 monthly fuel consumption totals. g) The monthly total is not a sum of the fuel sources due to an error in rounding. The total presented is the actual 2017 reported fuel total. m³ = cubic metre.


Table 9 provides a breakdown of the monthly solid waste incineration in metric tonnes at the Mine and compares these values to the monthly allocations as outlined in the 2007 Air Modelling Update (De Beers, 2007). This tables allow for year by year comparisons of the monthly and annual solid waste incinerated so that trends can be identified in the annual reports.

Monthly waste incineration in 2017 was below the monthly values predicted in the 2007 Air Modelling Update (Table 9) (De Beers, 2007).

Table 9 2017 Monthly Waste Tonnage Burned

Month

Waste Tonnage Burned 2010 (t)



Waste Tonnage Burned 2013 (t)(a)(b)





2007 Air Modelling Update (De Beers, 2007) (t)

January 15.17 51.41 15.00 0 17.89 16.09 7.50 1.30 27.31

February 13.71 27.02 16.29 0 14.12 13.83 6.49 1.25 25.55

March 15.17 42.79 14.49 0 30.17 14.98 7.14 0.83 27.31

April 14.69 18.21 14.37 0 13.93 17.99 6.27 0.70 26.43

May 15.49 16.93 15.24 0 33.53 15.15 3.61 0.83 27.31

June 13.46 15.27 13.73 50.49 13.85 17.78 2.60 0.88 26.43

July 15.52 24.41 18.70 50.22 15.67 18.58 1.58 0.69 27.31

August 14.71 29.65 14.32 31.83 16.66 17.16 3.25 0.84 27.31

September 15.42 77.32 15.24 15.95 14.45 14.70 2.52 0.51 26.43

October 15.26 28.52 15.59 7.00 15.98 16.30 2.24 0.47 27.31

November 14.61 20.23 15.25 15.63 15.76 16.49 2.39 0.28 27.31

December 15.10 20.80 12.96 25.73 17.35 13.56 2.90 0.47 27.31

Total 178.31 373.28 181.19 196.86 219.37 192.61 48.48 9.06 323.33

a) Incinerators were shut down February to May. Waste was shipped off-site until new incinerators were installed. b) Though the records indicate a small amount of diesel was burned for incineration in January, records do not indicate that waste was incinerated in January. t = tonne.

Incinerator Stack Testing Results

The Mine currently has two Ketek Model CY-100-CA-D incinerators, which began operation in June and August 2013. Stack testing of these incinerators in accordance with stack testing protocols outlined in the Canadian-Wide Standards for Dioxins and Furans (CCME, 2001) last occurred on July 11-15 2014. No stack testing was carried out in 2015, 2016 or 2017. For the 2014 stack testing results, refer to De Beers (2015).


4.4 EMISSIONS MITIGATION STRATEGIES

A number of mitigation measures have been integrated into the operations phase of the Mine to minimize air emissions. For combustion emissions such as SO2, NOX, particulate, dioxins, furans and mercury, the following mitigation measures are used:

• fuel conservation measures as appropriate to reduce SO2, NOX, and particulate emissions;

• CCME capable equipment to reduce NOX emissions; • waste diversion methods to minimize dioxins, furans, and mercury emissions from the

incinerator (see details in Section 3.1 of the Domestic Waste and Sewage Management Plan (De Beers, 2006b)

• operation of combustion equipment, particularly the incinerator, at optimal conditions (e.g., manufacturer recommended temperature, pressure, and other parameters); and,

• regular maintenance of the vehicle fleet and limiting of engine idling.

With the temporary closure of the Mine in December 2015, air emissions are expected to be significantly reduced during care and maintenance mode compared to during active mining operations.

4.5 FACILITY EMISSIONS

Methods

This section describes three methods that were used to estimate operations emissions (depending on the substance):

• using a mass balance approach; • using an emission factor approach (published or calculated); or, • using available intermittent source stack testing data.

The mass balance approach is based on the law of conservation of mass in a system. Essentially, if there is no accumulation within the system, then all the materials that go into the system are expelled. Fuel analysis data are a good example of the mass balance approach in predicting emissions. For example, if the sulphur content of a fuel is known, then the emissions of sulphur (in the form of SO2) can be calculated by assuming that all of the sulphur in the gas is emitted from the system.

The second approach is the use of emission factors. Emission factors are available for many emission source categories and are based on the results of source tests performed at one or more facilities within an industry. An emission factor is the contaminant emission rate relative to the level of source activity. Generic emission factors are commonly used when site-specific source monitoring data are unavailable.


The use of source specific stack testing data are appropriate for emission sources or substances that may be difficult to characterize using either mass balance or emission factors. A stack test measures the amounts of specific substances present in the stack exhaust gas.

The methods that were used for estimating emissions are as follows:

• SO2 – mass balance approach; • NOX – emission factor approach; • particulates – emission factor approach; • GHGs – emission factor approach; and, • dioxins, furans and mercury – stack test approach.

The following sections provide the data from the emissions calculations resulting from the use of each of the aforementioned approaches. The method is consistent with that used in the 2007 Air Modelling Update (De Beers, 2007).

Emission Calculation Results

Article VI Section 7.2 (part a, Item i) of the EAR (De Beers, 2002a) requires annual estimation of emissions from the facility, apportioned by major sources. Emission estimates of NOX, SO2, and PM (apportioned into TSP, PM10, and PM2.5) are required.

Emission calculations are based on fuel consumption and emission factors for the equipment at the Mine. The emission factors used are consistent with those used to develop the emissions profile that was simulated in the EAR (De Beers, 2002a) and the 2007 Air Modelling Update (De Beers, 2007), and are summarized in Table 10. Data provided by De Beers in 2017 indicate a diesel consumption of 5,864,479 litres (L) with a maximum sulphur content of 15 parts per million by weight and a waste oil consumption of 30,623 L with an assumed sulphur content of 20,000 ppm by weight. The 2017 emission estimates of the Mine are presented in Table 11.


Table 10 Emission Factors

Source

Emission Factors (g/GJ)

NOx TSP PM10 PM2.5

Power Generators(a) 1375.8 26.7 21.3 20.6

Mine Heaters/Incinerators(b) 61.8 10.0 6.8 4.9

Fleet 1263.6 45.9 45.9 45.9

Furnaces (diesel) 55.6(c) 10.0(b) 6.8(b) 4.9(b)

Furnaces (waste oil)(d) 58.7 309.9 247.0 139.5

(a) Based on published emission factors from USEPA AP-42 (U.S. EPA, 1995) for large stationary diesel engines (>600 hp). (b) Based on published emission factors from USEPA AP-42 (U.S. EPA, 1995) for utility residual oil-fired boilers/heaters using fuel No. 6. (c) Based on published emission factors from USEPA AP-42 (U.S. EPA, 1995) for residential furnaces. (d) Based on published emission factors from USEPA AP-42 (U.S. EPA, 1995) for waste oil combustion, using an assumed ash content of 1.57%.

Table 11 2017 Estimated Emission Rates

Source

Diesel Consumption (L/yr)

Emission Rates (t/d)(e)

SO2 NOX TSP PM10 PM2.5

Power Generators(a) 4,185,166 0.000303 0.6129 0.0119 0.00949 0.00918

Mine Heaters/Incinerators(b)

867,656 0.000063 0.0057 0.0009 0.00063 0.00045

Fleet(c) 760,618 0.000055 0.1023 0.0037 0.00372 0.00372

Furnaces(d) 5,1039 0.000004 0.0003 0.0001 0.00004 0.00003

Total 5,864,479 0.000424 0.7212 0.0166 0.0139 0.0134

Note: Diesel consumption totals by source are based on 2013-2015 ratios due to the 2017 source breakdowns being unavailable with the exception of the fleet total. a) Includes pumps, compressors, welders, and other equipment. b) Includes main and ancillary boilers/heaters. Consumption based on approximate monthly usage outlined in the 2015 Master Dip Sheet and Fuel-Enviro reports. c) Any fuel balance not accounted for in the yearly fuel consumption total is allocated to the fleet. d) Furnaces are using a mixture of diesel fuel (40%) and waste oil (60%), but are included in the total. e) Emission rate calculations use an assumed diesel/waste oil density of 881 kg/m3, a diesel heating value of 0.0441 GJ/kg, and a waste oil heating value of 0.0395 GJ/kg. g) The yearly total is not a sum of the fuel sources due to an error in rounding. The total presented is the actual 2017reported fuel total. L/yr = litres per year; SO2 = sulphur dioxide; NOX = oxides of nitrogen; TSP = Total Suspended Particulate; PM10 =particulate matter nominally less than or equal to 10 micrometres aerodynamic diameter; PM2.5 = particulate matter nominally less than or equal to 2.5 micrometres aerodynamic diameter; t/d = tonnes/day.

Table 12 presents the 2017 emission rates in tonnes per day (t/d) from the EAR (De Beers, 2002a) and compares these against the emission rates from 2006 to 2016. Overall, the emission rates in 2017 were lower than those reported for 2016. These differences are largely due to the reduced fuel consumption in 2017, as well as, the reduced volume of waste oil burned by the furnaces in 2017.


Table 12 Estimated Emission Rates Comparisons, 2006 to 2017

Compound Sources

2007 Air Modelling Update (De Beers, 2007) 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016(g) 2017(g)

SO2 (t/d)

Power Generators(a) 0.085 0.014 0.033 0.005 0.001 0.002 0.002 0.002 0.002 0.002 0.002 0.00120 0.00030

Mine Heaters and Incinerators(b) 0.171 0.003 0.035 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.00025 0.00006

Fleet(c) 0.048 0.007 0.032 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.00005 0.00006

Furnaces (d) (e) (f) - - - - - 0.015 0.030 0.000 0.006 0.006 0.016 0.00002 0.000004

Subtotal 0.304 0.024 0.068 0.007 0.002 0.017 0.032 0.002 0.008 0.008 0.019 0.0015 0.00042

NOX (t/d)



Fleet(c) 1.763 0.897 1.563 0.558 0.514 0.413 0.514 0.632 0.420 0.380 0.579 0.100 0.102

Furnaces (d) (e) (f) - - - - - 0.001 0.002 0.002 0.003 0.004 0.002 0.002 0.0003

Subtotal 8.636 2.06 2.557 3.187 3.342 3.979 4.254 3.983 4.523 4.533 5.122 2.564 0.721

TSP (t/d)



Fleet(c) 0.229 0.033 0.032 0.002 0.019 0.015 0.019 0.023 0.015 0.014 0.021 0.004 0.004

Furnaces (d) (e) (f) - - - - - 0.005 0.009 0.000 0.002 0.002 0.000 0.000 0.0001

Subtotal 0.325 0.071 0.084 0.110 0.108 0.132 0.145 0.100 0.111 0.112 0.117 0.059 0.017

PM10 (t/d)



Fleet(c) 0.102 0.033 0.026 0.002 0.019 0.015 0.019 0.023 0.015 0.014 0.021 0.004 0.004

Furnaces (d) (e) (f) - - - - - 0.004 0.007 0.000 0.002 0.002 0.004 0.000 0.00003

Subtotal 0.182 0.064 0.068 0.097 0.092 0.111 0.123 0.085 0.094 0.093 0.100 0.048 0.014

PM2.5 (t/d) Power Generators(a) 0.051 0.029 0.018 0.050 0.070 0.089 0.093 0.058 0.071 0.071 0.067 0.037 0.009



Compound Sources

2007 Air Modelling Update (De Beers, 2007) 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016(g) 2017(g)

Fleet(c) 0.068 0.033 0.021 0.002 0.019 0.015 0.019 0.023 0.015 0.014 0.021 0.004 0.004

Furnaces (d) (e) (f) - - - - - 0.003 0.006 0.000 0.001 0.001 0.002 0.000 0.00003

Subtotal 0.143 0.063 0.057 0.059 0.090 0.107 0.118 0.083 0.090 0.090 0.095 0.044 0.013

a) Includes pumps, compressors, welders, and other equipment. b) Includes main and ancillary boilers/heaters. Consumption based on approximate monthly usage outlined in the 2015 Master Dip Sheet and Fuel-Enviro reports. c) Any fuel balance not accounted for in the yearly fuel consumption total is allocated to the fleet. d) Furnaces are mainly using diesel fuel, but the 2013 total includes 60,000 L of waste oil. e) Furnaces are mainly using diesel fuel, but the 2014 total includes 30,000 L of waste oil. f) Furnaces are using a mixture of diesel fuel (40%) and waste oil (60%), but are included in the total. g) Emission rates based on 2013-2015 ratios due to the 2016 and 2017 source breakdowns being unavailable with the exception of the fleet totals. SO2 = sulphur dioxide; NOX = oxides of nitrogen; TSP = Total Suspended Particulate; PM10 =particulate matter nominally less than or equal to 10 micrometres aerodynamic diameter; PM2.5 = particulate matter nominally less than or equal to 2.5 micrometres aerodynamic diameter; t/d = tonnes/day; L = litre.


4.6 GREENHOUSE GAS EMISSIONS

Greenhouse gases are emitted from the combustion sources at the Mine. Article 7.2 (part a Item i-D) of the EAR (De Beers, 2002a) requires reporting of GHG emissions from Mine activities and specifies that GHGs must be apportioned as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O).

Estimates of the Mine’s GHG emissions in 2017 were based on emission factors published by Environment and Climate Change Canada (Environment and Climate Change Canada, 2016) and on fuel consumption data listed in Table 7. Since each reported GHG has a different Global Warming Potential, emissions of CH4 and N2O were converted to a carbon dioxide equivalent value (CO2e). Greenhouse gas emissions are reported in kilotonnes (kt) CO2e per year. Table 13 presents 2017 GHG emissions due to fuel combustion at the Mine. The total GHG emissions were estimated to be 59.55 kt CO2e.

Table 13 2017 Snap Lake Greenhouse Gas Emissions

Source CO2 CH4 N2O Total CO2e

Emission Factor (kg/m3) — — — —

Stationary Diesel Combustion(a) 2690 0.133 0.4 —

Off-road Diesel Mobile Combustion(a) 2690 0.15 1 —

Stationary Waste Oil Combustion(b) 2697 0.108 0.021 —

Global Warming Potential(b) 1 25 298 —

Emissions (kt/yr) 15.78 0.001 0.003 16.63

a) (Environment and Climate Change Canada, 2016) b) (USEPA, 2014) kt/yr = kilotonnes per year; CO2 = carbon dioxide; CH4 =methane; N2O = nitrous oxide; CO2e = carbon dioxide equivalent; - not applicable.

Table 14 presents a comparison of 2006 to 2017 GHGs. The GHG emissions in 2017 are lower than the 2016 emissions, due to the reduced annual fuel consumption.

Table 14 Annual Snap Lake Greenhouse Gas Emission Comparisons, 2006 to 2017

Compound 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

CO2 (kt/yr) 44.13 49.11 55.35 65.13 76.95 82.75 84.60 98.83 100.5 116.2 56.84 15.78

CH4 (kt/yr) 0.05 0.05 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.003 0.001

N2O (kt/yr) 2.00 2.23 0.02 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.009 0.003

Total CO2e (kt/yr) 46.18 51.39 62.51 68.23 80.61 86.68 88.63 103.4 105.2 122.3 59.55 16.63

kt/yr = kilotonnes per year; CO2 = carbon dioxide; CH4 =methane; N2O = nitrous oxide; CO2e = carbon dioxide equivalent.


5 CONCLUSIONS

Meteorological data collected included wind speed, wind direction, temperature, relative humidity, solar radiation, and rainfall. The Hill Station data were collected with a 69% retrieval rate for solar radiation, temperature, relative humidity, precipitation, and wind. The Lake Station data were collected with a greater than 74% retrieval rate for solar radiation, temperature, relative humidity, and wind. There was a zero percent retrieval rate for precipitation data from the Lake Station due to a malfunctioning sensor.

The 2017 monthly air temperature averages measured at both stations showed a similar pattern to temperatures measured in Yellowknife. In general, 2017 quarterly wind patterns were similar to 2016. Variations can be attributed to the different seasonal weather patterns that occur because annual wind predominance is influenced by the pattern of large scale weather systems that move through the region. Relative humidity measured at Snap Lake was consistent with patterns and ranges measured in Yellowknife. Relative humidity data is typically higher on average at Snap Lake than in Yellowknife and this could be attributed to overall slightly lower ambient temperatures but similar levels of absolute ambient moisture. Annual peak solar radiation occurred in June, consistent with previous years (2006, 2007, 2010, 2012, 2014, 2016), when the annual peak also occurred in June. The total annual rainfall recorded at the Hill Station for Snap Lake in 2017 was 92.46 mm, which is approximately 40.8% lower than the Yellowknife total for 2017 (156.1 mm) and 45.9% lower than the Yellowknife long-term (1981 to 2010) annual rainfall average of 170.8 mm; due to Snap Lake having lower monthly rainfall totals than Yellowknife in January, February, March, June, August, September, October, November, and December.

The passive monitoring of SO2 and NO2 in 2017 indicated concentrations well below their respective NWT AAQS. The annual average SO2 concentration is 0.12 µg/m3. This is a decrease of 0.14 µg/m3 from 2016. The annual average NO2 concentration is 0.32 µg/m3, which is a decrease of 0.20 µg/m3 from 2016.

Particulate monitoring was completed in 2017 for PM2.5. The TSP Partisols at the airstrip, wetland and explosives emulsion plant sites were decommissioned by the end of 2015, with ongoing monitoring by the 5030 SHARP PM2.5 monitors to fulfill regulatory requirements. The annual average PM2.5 concentration was 6.01 µg/m3 – slightly higher than the annual average in 2016 (5.31 µg/m3).

The total waste tonnage burned in 2017 was much lower than the total tonnage burned in 2016 and 2015. November 2017 had the least amount of waste tonnage burned at 0.28 tonnes.


A comparison of site-wide emission rates showed that 2017 emission rates are lower than those reported in 2016 due to a decrease in diesel fuel consumption and a decrease in waste oil burned. All emission rates remain lower than those predicted in the EAR (De Beers, 2002a) and in the 2007 Air Modelling Update (De Beers, 2007).

To date, the monitoring schedule outlined by the AQEMMP remains current. Any updates to the monitoring programs will be evaluated, updated and provided to the appropriate stakeholders to be reflective of the activities during Extended Care and Maintenance.


6 REFERENCES

AESRD, 2013. Alberta Ambient Air Quality Objectives and Guideline Summary. Alberta Environment and Sustainable Resource Development.

ARKTIS, 2017. Air Quality Monitoring Update for Care and Maintenance - Memorandum. CCME, 2001. Canada-Wide Standards for Dioxins and Furans Emissions from Waste

Incinerators and Coastal Pulp and Paper Boilers. Canadian Council of Ministers of the Environment. Winnipeg, MB, Canada.

CCME, 2000a. Canada-Wide Standards for Particulate Matter (PM) and Ozone. Canadian Council of Ministers of the Environment.

CCME, 2000b. Canada-Wide Standards for Mercury Emissions. Canadian Council of Ministers of the Environment.

De Beers, 2017. Snap Lake Mine Air Quality Meteorological Monitoring and Emissions Reporting 2016 Annual Report. De Beers Canada Inc.

De Beers, 2015. Snap Lake Mine, Air Quality Meteorological Monitoring and Emissions Reporting, 2014 Annual Report. Submitted to the Mackenzie Valley Land and Water Board. Yellowknife, NWT, Canada.

De Beers, 2008. Snap Lake Diamond Mine: Air Quality and Emissions Management and Monitoring Plan. Yellowknife, NWT, Canada.

De Beers, 2007. Snap Lake Diamond Project: Air Dispersion Modelling Update. Yellowknife, NWT, Canada.

De Beers, 2006a. Air Quality, Meteorological Monitoring and Emissions Reporting 2006 Annual Report. Submitted to the Mackenzie Valley Land and Water Board. Yellowknife, NWT, Canada.

De Beers, 2006b. Snap Lake Diamond Mine: The Domestic Waste and Sewage Management Plan. Submitted to the Mackenzie Valley Land and Water Board. Yellowknife, NWT, Canada.

De Beers, 2005. Snap Lake Diamond Project: Air Quality Monitoring Program. Submitted to the Government of the Northwest Territories and Environment Canada. Yellowknife, NWT, Canada.

De Beers, 2004. Snap Lake Diamond Project: Adaptive Management Plan. Submitted to the Mackenzie Valley Land and Water Board. Yellowknife, NWT, Canada.

De Beers Canada Inc., 2018. Snap Lake Diamond Mine: Air Quality and Emissions Management and Monitoring Plan. Yellowknife, NWT, Canada.

De Beers Canada Inc., 2017. Snap Lake Mine Extended Care and Maintenance Plan V2. Submitted to the Mackenzie Valley Land and Water Board in support of MV2011L2-004-Section 7.0: Interim Closure and Reclamation Plan. December.

De Beers Canada Inc., 2002a. Developer’s Environmental Assessment Report, Snap Lake Diamond Project.

De Beers Canada Inc., 2002b. Snap Lake Diamond Project Environmental Management System. Yellowknife, NWT, Canada.

Environment and Climate Change Canada, 2017. Historical Climate Data for Yellowknife “A” Meteorological Station.


Environment and Climate Change Canada, 2016. National Inventory Report: 1990-2014, Greenhouse Gas Sources and Sinks in Canada, Greenhouse Gas Division, Gatineau, Quebec, Canada.

Environment and Climate Change Canada, 2015. Canadian Climate Normals or Averages 1981 to 2010.

Environment and Climate Change Canada, 2013. Canadian Ambient Air Quality Standards. Environment and Climate Change Canada, 2011. National Ambient Air Quality Objectives. GNWT, 2014a. Guideline for Ambient Air Quality Standards in the Northwest Territories.

Department of Environment and Natural Resources. Government of the Northwest Territories.

GNWT, 2014b. 2014 NWT Fire Season Review Report. Government of the Northwest Territories.

GNWT and Environment and Climate Change Canada, 2006. Response Letter to De Beers Canada Inc.: Re: Snap Lake Project - Air Quality and Emissions Management Plan and Air Quality Monitoring Plan. Yellowknife, NWT, Canada.

GNWT and Environment Canada, 2006. Response Letter to De Beers Canada Inc.: Re: Snap Lake Project - Air Quality and Emissions Management Plan and Air Quality Monitoring Plan. Yellowknife, NWT, Canada.

Golder, 2014. Snap Lake Air Quality Action Level III Exceedance External Review and Action Plan Technical Memorandum. Prepared for De Beers Canada Inc. Calgary, AB, Canada. Golder Associated Ltd.

Government of British Columbia, 2016. Air Quality Objectives and Standards. Mekis, E., Vincent, L.A., 2011. An Overview of the Second Generation Adjusted Daily

Precipitation Dataset for Trend Analysis in Canada. Atmosphere-Ocean 49, 163–177. MVEIRB, 2003. Report of Environmental Assessment and Reasons for Decision on the De

Beers Snap Lake Diamond Project. Mackenzie Valley Environmental Impact Review Board.

U.S. EPA, 1995. AP-42, Fifth Edition, Compilation of Air Pollutant Emission Factors: Volume I: Stationary Point and Area Sources. Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina, USA.

USEPA (United States Environmental Protection Agency), 2014. Emission Factors for Greenhouse Gas Inventories.

Documents

2017 AIR QUALITY METEOROLOGICAL MONITORING AND … · 2018. 11. 23. · Snap Lake Mine - ii - March 2018 2017 Air Quality Meteorological Monitoring and Emissions Report Version 1