Gahcho Ku Project AEMP AEMP Workshop, Yellowknife, April 8, 2015 - - PowerPoint PPT Presentation

Gahcho Kué Project AEMP

AEMP Workshop, Yellowknife, April 8, 2015

AEMP P Wor

• rkshop

shop Agen enda da

Time me: : 8:30-1:00 1:00 PM Location

• n: Explo

lorer rer Hot Hotel l Janvier er Meet eting ng Room Confere rence nce Call Nu Number - 1-877-217-1261 Code 9293073# 1. 1. Introduction (De Beers)

• Workshop Objectives
• Mine Plan/Milestones
• AEMP WL Conditions
• AEMP Development – Regulatory and Engagement

2. Overview of AEMP (Golder)

• 3. Comments (De Beers/Golder)
• Traditional Knowledge
• Frequency of Sampling/Monitoring
• Analysis of the Data
• Action Levels
• 4. Wrap-up and Path Forward

2

Wor

• rksh

shop

• p Objectiv

ctives es

• Project Update/Project Milestones – align with AEMP Program and Re-design

timelines

• AEMP Design Plan
• Comments/Responses
• Action Levels

3

AEMP – Regulatory & Engagement

• Baseline

e studies - 1996

• Submission of EIS December 2010
• EIR Process – October 2011 to December 2012
• AE

AEMP Work rkshop shop - March arch 2013 13

• Site Work

rkshop hops - August 2013 13 - (As Aspect cts of the AE AEMP discussed) ed)

• EIR process concluded with Ministerial sign-off in October 2013.
• PLUP received November 2013
• Application for Type A Water Licence and Land Use Permit for Mining and Milling

submitted in November 2013

• AE

AEMP Work rkshop hop - February 2014

• Technical Sessions February 11-13, 2014
• AE

AEMP Work rkshop hop - March 2014

• Public Hearing May 2014
• Water Licence / Land Use Permit issued

September 2014

• Board Decision on AEMP – December 2014

4

5

Hearne 5034 Tuzo

Location of Kimberlite Pipes in Kennady Lake

Area 5 Area 6 Area 7 Area 4 Area 3 Area 1 Area 8 Area 2 Dyke A Dyke C Dyke D Dyke E Dyke F Dyke G

Construction (2015)

Area 5 Area 4 Area 3 Area 1 Area 8 Area 2 Area 7 Area 6 Dyke A Dyke A1 Dyke F Dyke G Dyke H Dyke

I

Dyke J Dyke K Dyke L

Construction (2015-2016)

Discharge Water ~21 Mi m3 Discharg e Water ~1.5 -2 Mi m3

Area 8 Area 6 Area 7 South Mine Rock Pile Fine PKC Facility West Mine Rock Pile Tuzo Hear ne Coarse PK pile 5034 B Dyke L A Dyke C D E F G H

I M

K N

Operations (2016-2018)

5034 Hearne Operational Discharge Water ~3.4 Mi m3 - ~ 2months of discharge Groundwater inflows 5034 ~5,200 m3/day and Hearne ~ 3,000m3/day

Estimated Inflows into Pits (5034 and Hearne)

9

11

GK SNP Locations – Construction and Operations

12

Review Water Licence Conditions – AEMP

(Part I, item 2; Schedule 6, Part I)

13

Preparation of an AEMP Design Plan – current to Sept 2019

• Conceptual site model with clearly defined testable hypotheses for the AEMP and

assessment and measurement endpoints

• Monitoring for the purpose of measuring Project-related effects on the following

components of the Receiving Environment

• Hydrology
• Surface water quality
• Sediment quality
• Lower trophic organisms
• Fish habitat, fish health and fish

tissue chemistry

• Assessing dispersion of mine discharges
• Sampling and Analysis Plan
• Summary of how TK will be incorporated into AEMP studies
• Description of the AEMP Response Framework

Review Water Licence Conditions - AEMP

14

• Revision of the AEMP Design Plan (Version 4)

– May 2015

• Submission of an AEMP Annual Report

– May of each year

• Submission of the Aquatic Effects Re-

evaluation Report – July 2019 (and every 3 years thereafter)

• Description of Project-related effects since

Project inception

• Revise prediction
• Provide supporting evidence for any

proposed revisions to the AEMP Design Plan update

• Development of an AEMP Response Plan
• Required if any low action level is

triggered

AEMP Design Plan – 2015 to 2019

This AEMP monitoring period:

• 2 years construction and 2 years operation

Key Project activities:

• 2 years of dewatering
• WQ consistent between Area 3 and Lake

N11, and Area 7 to Area 8 (if required)

• Dewatering regulated by TSS EQC and

Action Levels

• First 2 years of planned operational discharge

to Lake N11 and possibly 1 year to Area 8

• Operational discharge regulated by EQCs

15

Lake N11 EQCs (Operations)

16

WQ Constituent EQCs Predicted Discharge Quality MAC (mg/L) MGC (mg/L) Year 1 (2017) Year 2 (2018) Ammonia 10 20 6.6 8.0 Sulphate 150 300 14 23 Nitrate 10 20 6.5 7.9 Total Phosphorus 0.03 0.06 0.02 0.03 Chloride 160 320 35 85 Fluoride 0.15 0.3 0.08 0.12 Aluminum 0.1 0.2 0.068 0.085 Chromium 0.002 0.004 0.001 0.0018 Copper 0.003 0.006 0.002 0.0024 Iron 0.4 0.8 0.2 0.29 Molybdenum 0.3 0.6 0.003 0.004 Nickel 0.09 0.18 0.0035 0.0045 Uranium 0.06 0.12 0.0012 0.0019 TSS 15 25

AEMP Study Design Overview

Monitoring Locations: – Core lakes

• Area 8, Lake N11, Lake 410, and Kirk

Lake

– Reference lakes

• Reference Lake 3 and East Lake

– Raised lakes

• Lakes A1, D2 and D3, and J1

– Downstream lakes and streams

• L and M watersheds between Area 8

and Lake 410

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AEMP Study Design Overview

Reference Lakes:

• East Lake is general similar to the core

lakes in terms of water and sediment quality and lower trophic communities

• Refere

rence ce Lake 3 has a shallower depth, more similar water and sediment quality to core lakes, and more abundant benthic community (compared to Reference Lake 2)

18

AEMP Study Design Overview

• All components follow a common

sampling design

• Component sampling methods include

field observations and/or measurements, and sample collection for laboratory analyses

• Data analyses are conducted on a

component-specific basis, but include the same statistical comparisons

• Each component follows a quality

assurance / quality control process

19

AEMP – 2015-2019

Waterbody/ Watercourse Predicted Change in Hydrology Predicted Change in Water Quality Hydrology Water Quality Plankton Sediment Quality Benthic Invertebrates Fish Habitat and Community Fish Health Fish Tissue Chemistry Lake N11 increased flow-through; increased flow at outlet; slight increase in water level negligible Y (AEMP and SNP) Y (AEMP and SNP) Y Y (AEMP and SNP) Y N Y Y Other N lakes increased flow-through some N lakes, particularly N14 negligible Y (Lakes N14 and 17) N N N N N N N Lakes D2, D3 increased water level minor changes (water and sediment quality) Y Y Y Y Y N N Y Lake J1 increased flow-through due to diversion from Lake A1 (Area 1) negligible Y N N N N N N N Area 8 increased flow-through; increased flow at outlet negligible Y (AEMP and SNP) Y (AEMP and SNP) Y Y Y N Y Y Area 8 outlet Stream K5 and L and M streams increased flow negligible Y (Stream K5) Y (Streams K5 and L2) N N Y Y (L and M Streams) N N Subset of L and M lakes increased flow-through; increased flow at outlet; minor increase in water level negligible Y (Lakes L1 and M1) Y (Lakes L2 and M4) N N N N N N Lake 410 increased flow-through; increased flow at outlet negligible Y Y N N N N N N Kirk Lake increased flow-through; increased flow at outlet negligible Y N N N N N N N East Lake none none Y Y Y Y Y N Y Y Reference Lake 3 none none Y Y Y Y Y N Y Y Kennady Lake Areas 2 to 7 partly dewatered, Areas 3 and 5 become WMP (not applicable) N (SNP only) N (SNP) N N N N N N

AEMP Design Plan - Board Decision Review

• Board Decision on AEMP Design Plan issued December 2014 (Water Licence

MV2005L2-0015)

• Current AEMP Design Plan addresses the construction and early operations

phases of Gahcho Kué Mine

• 69 of 78 responses to Board comments were deemed acceptable, with

recommendations, where applicable, to incorporate responses into the next version of the Plan

• 9 responses required follow-up:
• Sampling frequency (9, 42)
• Incorporation of TK (44)
• WQ/sampling locations (50)
• Plankton baseline data sufficiency (52)
• Action levels (57, 58, 60, 61)

21

Response #9 - Sampling Frequency

Concern:

• Will the period between monitoring cycles

be reduced based on monitoring results?

• Response provided was an incorrect entry

Correct response:

• The statement that sampling frequency may decrease in operations was made to

indicate the expectation that following the cessation of operational discharge to Lake N11 (at the end of Year 3), measurement endpoints would begin to trend back to existing conditions

• However, an increase in monitoring frequency of a component or a specific

parameter due to prior monitoring results, particularly during the operational discharge may occur (e.g., a low action level trigger or the result of a special study)

• De Beers will adjust the text in the next version of the AEMP Design Report to

reflect these considerations

22

Response #42 – Monitoring Frequency

Concern

• De Beers must clearly outline the monitoring frequency over the period of this

version of the AEMP is in place Monitoring Plan

• the AEMP sampling frequency for this AEMP

version will be annual during 2015 to 2019 (not 2015 to 2018 as stated in the IR response)

• rationale for any changes to sampling frequency

for the 2020 AEMP or future AEMPs will be discussed in the AEMP re-evaluation report to be submitted in July 2019, and proposed in the next AEMP Design Plan, due September 2019

• Text in the Plain Language Summary updated

23

Response #44 – Incorporating TK into AEMP

Concern

• Separate TK monitoring programs should be

referenced in the AEMP and the AEMP should describe how the results gathered in these monitoring programs will be evaluated in the AEMP Monitoring Plan

• De Beers and five Aboriginal Parties have recently signed the Ni Hadi Xa

agreement

• Traditional monitoring component to be further refined and developed through

input of this group as well as ongoing community meetings

• 2015 traditional monitoring include:
• Establishing a cabin; hiring 1 full time TK monitor and 1 part-time TK monitor
• Traditional monitoring in the downstream (consideration to Fletcher Lake)

including several TK indicators, including fish-tasting

24

Response #50 – WQ Sample Locations

Concern:

• How will water quality sample locations be determined?

Monitoring Plan:

• The location of the stations will be “field fit”
• Water quality sample locations will be finalized in the field using the following

criteria:

• Focus on basin near discharge at N11
• co-locate with benthic invertebrate community

and sediment quality samples

• co-locate with plankton samples
• similar depth and substrate to other stations
• same or similar locations as previous monitoring or baseline programs

25

Response #52 – Plankton Monitoring and Baseline

Concern:

• Is there sufficient baseline data for plankton downstream of the Project?
• Is it appropriate to collect additional baseline data in downstream lakes

after the Project has commenced? Monitoring Plan:

• Sufficient plankton baseline data exist for downstream lakes including:

Area 8, Lake N11, L and M lakes, and Lake 410.

• 4 years of baseline data will have been collected prior to predicted

changes

• Collecting baseline downstream after Project commencement is a

reasonable approach for plankton

• No chemistry changes predicted during this period
• SNP monitoring will proceed – early indicator
• Timing issue – best to time to collect baseline data is just before

effects are likely to occur

26

Response #58 - Action Level for Sediment Quality

Concern:

• Board staff recommended that the low action level

criteria be reviewed and revised with consideration for the sediment quality benchmarks and normal ranges. Monitoring Plan:

• The low action level criteria for sediment quality have been updated to include:
• Concentration at AEMP station nearest the discharge is greater than normal

range, OR relative difference between core lake and reference lakes statistically significant compared to baseline; AND

• Concentration at AEMP station nearest the discharge exceeds benchmark
• Confusion around benchmark being set within the normal range
• The benchmarks are based on general CCME guidelines
• Site-specific baseline concentrations could exceed CCME guidelines so low

action level is set to include both normal range and benchmark exceedances

27

Concern:

• What is the rationale for when a human health risk assessment would be initiated?

Monitoring Plan:

• It is anticipated that human health and/or wildlife risk assessment activities would

be initiated as part of response planning if a Low Action level is reached

Response #60 – Action Level for Water Quality

28

Concern:

• Low action level (nutrient enrichment)

for WQ – exceedance of EIS predictions warrant further investigation regardless if AEMP benchmarks are not exceeded Monitoring Plan:

• Low action level for WQ:
• Exceedance of EIS predictions; AND
• Exceedance of 75% of AEMP

benchmark; AND

• Statistically significant relative difference

between core lake and reference lakes compared to baseline

Response #61 – Action Level for Water Quality (nutrient enrichment)

29

Review of Action Levels

Effects due to Project Activities

• Toxicity from operational discharge or inputs from mine structures
• Nutrient enrichment from operational discharge or seepages form

mine structures

• Habitat alteration (flow changes during dewatering)

30

Low Action Levels

31

General Criteria

• Comparison to normal range (change is outside of natural variability)
• Statistical significance (change is not occurring at reference lakes)
• Comparison to EIS predictions (change is larger than predicted)
• Comparison to benchmark (change is larger than effect threshold)
• Link to mine (change is a result of the mine)

Toxicological Impairment Low Action Level – Water Quality

32

Water Quality

Substances of potential toxicological concern Measured toxicity at end-of-pipe

Lake-wide concentration greater than normal range supported by a temporal trend AND Concentration exceeds 75% of AEMP benchmark AND Divergence of trends in concentrations compared to those in reference lakes Persistent sublethal toxic effects to test organisms

• ther than fish in end-of-pipe samples

AND No sublethal toxic effects for fish in end-of-pipe samples Water Quality

Substances of potential toxicological concern Measured toxicity at end-of-pipe

Lake-wide average concentration greater than normal range and supported by a visual temporal trend AND Lake-wide average concentration exceeds 75% of AEMP benchmark AND Relative difference between core lake and reference lakes statistically significant compared to baseline (i.e., significant BACI effect detected) Sublethal toxic effects to test organisms other than fish in three consecutive end-of-pipe samples Version 3 Version 4

Toxicological Impairment Low Action Level – Sediment Quality

33

Sediment Quality Concentration exceeding AEMP benchmarks(b) as a result of the Mine(c) AND Concentration is greater than normal range AND Divergence of trends in concentrations compared to those in reference lakes Sediment Quality Concentration at AEMP station nearest the discharge is greater than normal range, OR relative difference between core lake and reference lakes statistically significant compared to baseline (i.e., significant BACI effect detected) AND Concentration at AEMP station nearest the discharge exceeds AEMP benchmark Version 3 Version 4

Toxicological Impairment Low Action Level – Plankton Community

34

Plankton Community A decline below the normal range in total phytoplankton biomass, or zooplankton abundance

• r biomass

AND Divergence of trends in total phytoplankton biomass, or zooplankton abundance or biomass, compared to those in reference lakes Plankton Community Lake-wide average value for total phytoplankton biomass, zooplankton abundance, or zooplankton biomass less than normal range OR Relative difference in total phytoplankton biomass, zooplankton abundance, or zooplankton biomass, between core lake and reference lakes statistically significant compared to baseline (i.e., significant BACI effect detected) Version 3 Version 4

Toxicological Impairment Low Action Level – Benthic Community

35

Benthic Community Decline below the normal range in total density, richness or densities of dominant taxa AND Divergence of trends in total density, richness, or densities of dominant taxa compared to those in reference lakes Benthic Community Lake-wide average value for total density, richness or densities of dominant taxa less than normal range OR Relative difference in total density, richness, or densities

• f dominant taxa, between core lake and reference lakes

statistically significant compared to baseline (i.e., significant BACI effect detected) Version 3 Version 4

Toxicological Impairment Low Action Level – Fish Health

36

Fish Health Statistically significant difference in fish health endpoints or fish tissue chemistry that is beyond normal range AND Change is in direction, and of magnitude, that is indicative of an impairment to fish health Fish Health Average value for fish health endpoint outside of normal range and in the direction that is indicative of a toxicological effect AND A statistically significant difference in fish health endpoint relative to reference lakes that exceeds the critical effect size Version 3 Version 4 Fish Tissue Average value for fish tissue chemistry parameter above normal range AND A statistically significant difference in fish tissue chemistry parameter relative to reference lakes and relative to baseline

Toxicological Impairment Low Action Level – Fish Consumption

37

Fish Consumption by Humans Fish Good to Eat Fish taste and/or texture not acceptable. OR Metals in edible fish tissue above normal range. Fish Consumption by Humans Fish Good to Eat Fish taste and/or texture that is not acceptable AND Average concentration of a metal in edible fish tissue above normal range Version 3 Version 4

Toxicological Impairment Low Action Level – Drinking Water

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Drinking Water for Humans Water Must be Drinkable Drinking water parameter at any location above 75% of HC human health or aesthetic drinking WQG Drinking Water for Humans Water Must be Drinkable Concentration of a drinking water parameter at any location above 75% of Health Canada’s human health or aesthetic drinking water quality guideline Version 3 Version 4

Nutrient Enrichment Low Action Level – Water Quality

39

Water Quality Concentrations exceeding EIS predictions supported by temporal trend AND Exceeding 75% of AEMP Benchmark AND Divergence of trends in concentrations compared to those in reference lakes Water Quality Lake-wide average concentration exceeds EIS predictions and exceedance is supported by a visual temporal trend AND Lake-wide average concentration exceeds 75% of AEMP benchmark AND Relative difference between core lake and reference lakes statistically significant compared to baseline (i.e., significant BACI effect detected) Version 3 Version 4

Nutrient Enrichment Low Action Level – Plankton Community

40

Plankton Community Persistent increase beyond the normal range in total phytoplankton or zooplankton biomass OR An ecologically relevant change in phytoplankton

• r zooplankton community composition

AND Divergence of trends in total phytoplankton or zooplankton biomass, compared to those in reference lakes Plankton Community Lake-wide average value for total phytoplankton biomass, zooplankton abundance, or zooplankton biomass persistently (three consecutive years) above normal range OR An ecologically relevant change in phytoplankton or zooplankton community composition OR A statistically significantly relative difference in total phytoplankton biomass, or zooplankton abundance or biomass, between core lake and reference lakes compared to baseline (i.e., significant BACI effect detected) Version 3 Version 4

Nutrient Enrichment Low Action Level – Benthic Community

41

Benthic Community Increases above normal range(a) in total density, richness, or densities of dominant taxa AND Divergence of trends in total density, richness or densities of dominant taxa compared to reference lakes Benthic Community Lake-wide average value for total density, richness or densities of dominant taxa greater than normal range OR Relative difference in total density, richness, or densities

• f dominant taxa, between core lake and reference lakes

statistically significant compared to baseline (i.e., significant BACI effect detected) Version 3 Version 4

Nutrient Enrichment Low Action Level – Fish Health

42

Fish Health Statistically significant difference in fish health endpoints or fish tissue chemistry that is beyond normal range AND Change is in direction, and of magnitude, that is indicative of an impairment to fish health Version 3 Version 4 Fish Health Average value for fish health endpoint outside of normal range and in the direction that is indicative of a nutrient enrichment effect AND A statistically significant difference in fish health endpoint relative to reference lakes that exceeds the critical effect size Fish Tissue Average value for fish tissue chemistry parameter above normal range AND A statistically significant difference in fish tissue chemistry parameter relative to reference lakes and relative to baseline

Habitat Alteration Low Action Level – Hydrology

43

Hydrology Open water: Flows exceed the 2-year flow level during pumping (dewatering and operational discharges) OR Evidence of widespread bank instability (i.e., bank slumping in the range of 0.5 m by 3 m in length, or greater) Under ice: Water levels (piezometric head) in lakes along the dewatering flow path exceed the 10-year water level during pumping (dewatering and operational discharges) OR Channels along the dewatering flow path exhibit large scale and progressive aufeis buildup above the bankfull elevation causing an increase in upstream lake water levels Version 3 = Version 4

No Version Change

Habitat Alteration Low Action Level – Benthic Community

44

Benthic Community Decreases below normal range(a) in total density, richness, and densities of dominant taxa, indicating scouring AND Change in community composition indicating an adverse flow-related effect Benthic Community Average value for total density, richness or densities of dominant taxa less than normal range, indicating scouring AND Change in community composition indicating an adverse flow-related effect Version 3 Version 4

Habitat Alteration Low Action Level – Fish Habitat, Community and Health

45

Fish Habitat, Community and Health Changes in fish habitat, community or health

• utside normal range that are consistent with

effects related to increased water level (beyond EIS predictions) OR Changes in fish habitat, community or health

• utside normal range that are consistent with

effects related to increased flow (beyond of EIS predictions) Version 3 = Version 4

No Version Change

Analysis of AEMP Component Data

• The general approach to assessing effects involves answering these

questions:

• Is the measurement endpoint outside of the range of natural

variability? (Comparison to normal range)

• Is the pattern of observations for a measurement endpoint at the

core lakes consistent with the reference lakes? (Statistical comparison using a Before-After Control Impact [BACI] design)

• Other criteria are also used (e.g. comparisons to AEMP benchmarks)

46

What is the Normal Range, and how is it Defined?

• Normal range – range that represents 95% of reference or baseline values
• Has traditionally been defined as the mean ± 2 standard deviations
• Captures approximately 95% of data when:
• sample sizes are large; and
• when data follow a bell shaped distribution

47

95%

What is the Normal Range, and how is it Defined?

• Assumptions are typically violated and the mean ± 2 SD can provide

unrealistic bounds

• e.g. total density (-400, 1550)
• Traditionally, the mean at the exposure site was compared to the normal

range for an individual observation (this is not an early warning indicator)

48

What is the Normal Range, and how is it Defined?

• De Beers funded research to develop appropriate statistical methods to define

the normal range

49

What is the Normal Range, and how is it Defined?

• Idea is to estimate the range of natural variability for a single observation or

the mean of some number (m) observations

• Questions we want to answer are:

If we have one value of a measurement endpoint: Is the observed value outside the expected range of values that we would see if the mine wasn’t there? If we have 10 randomly selected values: Is the average of the 10 observed values outside of the range of where the average of 10 samples would be if the mine wasn’t there?

50

Normal Range – An Example

• Consider a school with children aged 6 to 18.
• The normal range (captures 95%) for the age of children in the school could be

6 to 18

• 5 year old or a 20 year old would be outside of the normal range

51

Normal Range – An Example

• If we randomly select 10 students from the school, should we compare the

average of their ages to the range 6 to 18?

52

Example: normal range

• The normal range for the average age of the 10 students is narrower (more like

10 to 14)

• It would be highly unlikely to randomly select all young students and have the

average of 10 students being 7 or 17

53

What is the Normal Range, and how is it Defined?

• The new approach is to define the normal range for the average value of the

endpoint

• Normal ranges are generally narrower than the traditional approach
• The use of the new approach answers the question:

On average, are the observed values outside of the range of values that we would see if the mine wasn’t there?

• What does it mean to be outside of the normal range?
• On average, the observed values are unusual (only likely to happen 5% of

the time if there are no mine-related effects)

• Does not address ecological significance (it is an early warning indicator)

54

Statistical Approach

• Key questions:
• Is the measurement endpoint different from baseline?
• Is the measurement endpoint changing over time?
• If the measurement endpoint has changed, was the same change observed at

the reference sites?

• Approach: Before-After Control-Impact (BACI) design
• Before-After – baseline data pre-construction vs. data post-construction
• Control-Impact – data collected from reference sites and test sites
• Use to detect long-term (press) and short-term (pulse) responses

55

Statistical Approach: Before-After

• Is the measurement endpoint different from baseline?
• Is the measurement endpoint changing over time?

56

Statistical Approach: Before-After/Control-Impact

• If the measurement endpoint has changed, was the same change
• bserved at the reference sites?
• Note that it is ok that reference sites are different

57

Statistical Approach: Before-After/Control-Impact

• Pulse response (short-term)
• Press response (long-term)

58

Pulse Press

Changes not Linked to the Mine?

• Example:
• Increase from baseline but change is also seen at reference sites (e.g., could

be linked to climate change or fires)

59

Worked Example – Data Analysis

60

General Criteria for Low Action Level

• Comparison to normal range (change is outside of natural variability)
• Statistical significance (change is not occurring at reference lakes)
• Comparison to EIS predictions (change is larger than predicted)
• Comparison to benchmark (change is larger than effect threshold)
• Link to mine (change is a result of the mine)

Worked Example – Data Analysis

• Example: water quality constituent
• 2 years of before data
• 2 years of after data
• 3 open water sampling periods per year
• 2 Reference lakes
• 5 sampling stations per lake

61

Worked Example – Data Analysis

62

Worked Example – Data Analysis

• Significant BACI effect can be

detected in year 1

63

Path Forward

64