An Update on Monitoring Activities for the Giant Mine Remediation - - PowerPoint PPT Presentation

An Update on Monitoring Activities for the Giant Mine Remediation Project Working Group Meeting July 9, 2015

1 MV2007L8-0031

What is the purpose of the GMRP Baseline Investigations and Monitoring Activities?

• To contribute to the Long Term Environmental

Monitoring Program, which will consist of all monitoring activities at Giant Mine

• Components are:

– regulatory requirements; – non-regulatory (due diligence) requirements; – commitments made; and – monitoring to address public input or concern.

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Program Objectives

• Over the longer term, these activities will help to inform:

– the planning process for remediation activities; – predicting how the ecosystem will respond to remediation activities; and – the identification of scientific data gaps that need to be filled in order to advance the planning and implementation of remediation activities.

• As well, these components are, in part, designed to fulfill

project regulatory requirements.

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Regulatory Monitoring “Programs”

• 1. Surveillance Network Program (SNP)/Operational

Monitoring Program (OMP)

• 2. Metal Mining Effluent Regulations (MMER)

including Environmental Effects Monitoring (EEM)

• 3. Aquatic Effects Monitoring Program (AEMP) – will

be developed as part of the preparation for the Water Licence (planning only this year)

• 4. Wildlife Management Program (WMP) – will be

developed as part of the preparation for the Water Licence (planning only this year)

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Other Monitoring Components

• Air quality monitoring program (AQMP)
• Due diligence (non-regulatory) monitoring

– terrestrial & aquatic ecosystems

• Freeze Program – to be determined
• Cumulative effects – will be developed as part
• f the preparation for the Water Licence

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Surveillance Network Program (SNP) Objectives

• Surface water monitoring to confirm effluent

discharge volume, quality and treatment performance

• Currently being completed under former Water

Licence requirements that will need to be revised when the new treatment plant and treated effluent discharge pipe are constructed (the outfall location will be selected via engagement initiatives)

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SNP/MMER Sample Points

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Operational Monitoring Program (OMP) Objectives

• Various, non-regulatory monitoring requirements

being performed by the Care & Maintenance contractor

• Program includes surface water (ponds sumps)

and effluent treatment plant (ETP) performance and formerly included other tasks including shallow and deep groundwater wells

• Portions of the OMP will continue and/or morph

as the project moves out of C&M

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OMP Surface Water Sample Points

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SNP/OMP Results for 2014/2015

• Effluent Treatment Plant (ETP) operated for 65

days between June 12 & September 25, 2014 (suspended for 32 days from August 9-September 9 due to low water levels).

– Total effluent discharged: 228,004 m3 – 22.9% less than 2013/2014 due to dry conditions

• Former Water Licence requirements met

– Effluent discharged to Baker Creek contained total Arsenic concentrations between 0.240 mg/L and 0.405 mg/L (average of 0.311 mg/L). – The applicable criteria are 0.500 mg/L.

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Metal Mining Effluent Regulation (MMER) & Environmental Effects Monitoring (EEM)

• MMER/EEM: Weekly and monthly surface water

monitoring to ensure effluent discharge quality for specific metals and toxicity

• This program is completed annually to fulfill regulatory

requirements under the Fisheries Act, MMER/EEM

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MMER Surface Water Sample Points

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MMER/EEM Results for 2014/2015

• Sampling took place three times only due to short

discharge period: July 15, August 18 and September 22, 2014

• Treated effluent was not acutely toxic
• Survival of test organisms not affected by treated effluent
• Sub lethal toxic effects related to survival and/or

reproduction observed in two species in the August 18 sample

• Concentrations of applicable parameters were below

criteria for all sampling events

• Results are consistent with those from previous years

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MMER/EEM Plan for 2015/2016

• In consultation with Environment Canada,

Phase 5 of the EEM program will be designed for implementation in 2016/2017

• The details of the scope of the EEM Phase

5 have not been developed yet but currently looking at two main options, one

• f which, a Periodic Monitoring –

Surveillance Study is preferred by GMRP

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Baseline Work in Aquatic Environments

• The characterization of the baseline aquatic

environment at the site is nearing completion

– required in order to establish a starting point for the remediation project to which progress can be compared

• A data gap analysis is currently being completed

in order to determine whether or not additional baseline work in the aquatic environment is required

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Baseline Work in Aquatic Environments

• Completed and presented in 2013/2014:
• 1. Yellowknife Bay Baseline Aquatics Study
• 2. Yellowknife Bay and Lower Martin Lake Fish

Collection and Tissue Analysis Study

• 3. Lower Martin Lake and Upper Baker Creek

Baseline Aquatics and Sediment Studies

• 4. Yellowknife Bay Hydrodynamic Modelling

Study

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Baseline Work in Aquatic Environments Completed in 2014/2015

1. Foreshore Tailings Area Underwater Aquatic Habitat Survey 2. Baker Creek Outlet Ecological Assessment & Comparative Hydrodynamic Modelling 3. Baker Creek Outlet Sediment & Pore Water Characterization (underway; completion in July/August 2015) 4. Metal Concentrations in Sediments and Surface Waters adjacent to N’Dilo and Dettah in Yellowknife Bay (follow-up program to be completed in 2015/2016) 5. Baseline Aquatics & Fisheries Studies in Gar Lake, Trapper Lake, Upper Shot Lake and Lower Shot Lake (for the Baker Creek north diversion evaluation in response to Measure 11 from MVEIRB on the Report of EA) 6. Upper Baker Creek Sediment & Surface Water Characterization Study 7. Site Runoff & Storm Event Surface Water Quality Sampling Program – There are also other non GMRP-funded ongoing and completed projects

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Foreshore Tailings Area (FTA) Underwater Aquatic Habitat Survey Objectives/Scope/Findings

• Aquatic habitat survey involved an underwater video

survey of the FTA to describe and characterize the aquatic habitat present.

• The underwater survey was completed over three days

in October 2014 using an underwater drop camera to collect colour video footage of substrate in the study area.

• Little viable fisheries habitat or utilization noted during

survey.

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FTA Underwater Aquatic Habitat Survey

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Baker Creek Outlet (BCO) Ecological Assessment & Comparative Hydrodynamic Modelling

• Comparative hydrodynamic modelling was undertaken to

assess the potential ecological effects of diverting the Baker Creek outlet area—In other words, how will re- routing Baker affect the creek mouth from a hydrodynamic perspective?

• The ecological importance of the outlet area to the
• ngoing productivity of Yellowknife Bay was also

assessed.

BCO Ecological Assessment & Comparative Hydrodynamic Modelling

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BCO Ecological Assessment & Comparative Hydrodynamic Modelling Results for 2014/2015

• An analysis of six scenarios was developed for

the creek mouth.

• The focus was on developing each option to

mitigate potential weaknesses or threats, and

• pportunities to enhance local habitat and fish

productivity.

• A summary of results is difficult to present,

however, if water levels decrease or become intermittent, ecological and hydrological integrity

• f BCO will be affected.

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Baker Creek Outlet (BCO) Sediment & Pore Water Characterization Objectives

• Study designed to address data gaps in the

understanding of Arsenic in the BCO

– Potential sediment toxicity and how it relates to the aquatic environment – Arsenic mobility within the sediment and between the sediment surface and the water column, and potential effects on aquatic

• rganisms

– Estimate of the volume of contaminated sediments present in the BCO

• Report due mid 2015—stay tuned.

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Upper Baker Creek (UBC) Sediment & Surface Water Characterization Objectives

• Address data gaps in the understanding of Arsenic

concentrations in UBC

• Use multiple lines of evidence (LOEs) to assess the

distribution and chemical signature of arsenic-contaminated sediments, particularly to determine whether sediments from LML and UBC are affected by natural or anthropogenic (originating from human activity) sources.

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Upper Baker Creek (UBC) Sediment & Surface Water Characterization

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Upper Baker Creek (UBC) Sediment & Surface Water Characterization Results for 2014/2015

• Elevated concentrations of total arsenic are present in all of Upper Baker

Creek (Reach 7 to 11) sediments sampled as well as small unnamed lakes near the creek.

– Elevated concentrations are pronounced in wetland areas – Distribution of arsenic is patchy, (similar to lower Baker Creek on the Mine: Reach 0 to 6).

• Sediment arsenic concentrations in upper Baker Creek (Reaches 7 to 11)

ranged from 16 to 746 mg/kg.

• Sediment arsenic concentrations in the unnamed Lakes ranged from 500-

1,200 mg/kg.

• Arsenic speciation results indicate that arsenic trioxide is present in all

samples tested--this substance is rarely observed under natural conditions, indicating that it is from a man-made source.

• Arsenic levels in surface water were above FWAL CCME criteria in most of

the samples collected. There was no correlation based on distance from Mine.

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Upper Baker Creek (UBC) Sediment & Surface Water Characterization Results for 2014/2015

• The bioaccessibility of the arsenic ranges from 9% to 44% - this is the

portion of the arsenic available for uptake by humans and aquatic organisms.

• Lower reaches of Baker Creek (6 & 7) had the highest

bioaccessibility percentages

• The primary source of the arsenic in Lower Martin Lake and

downstream through Upper Baker Creek is likely from the Mine

– Roaster stack is the primary source of the man-made arsenic via atmospheric (air-borne) deposition onto the land and subsequent runoff to the creeks and lakes.

• Use of data shared by other researchers in the study area was cost-

effective and successful.

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(Community Monitoring) Metal Concentrations in Sediments and Surface Waters adjacent to N’Dilo and Dettah in Yellowknife Bay

• Measure metal concentrations in sediments and surface water at

locations adjacent to the communities of N’Dilo Dettah

– Locations commonly used by community members – 5 sites in N’Dilo and 4 site in Dettah – Communities of Dettah and Ndilo involved in study, including a training component for community members to learn sampling techniques. – Collaborative effort between Environment Canada, the GNWT Cumulative Impacts Monitoring Program (CIMP) and the Yellowknives Dene First Nation (YKDFN) – The results from a CIMP study 19 other lakes in the area were used for comparison

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Sample Locations in Sediments and Surface Waters adjacent to N’Dilo and Dettah in Yellowknife Bay

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Metal Concentrations in Sediments and Surface Waters adjacent to N’Dilo and Dettah – 2014 Results

• Sediment
• Arsenic was elevated in offshore sediments at Ndilo (7-284 mg/kg; averaging 271

mg/kg), consistent with inputs from mining, although arsenic concentrations were within the range of other Yellowknife area lakes.

• Sediments near Dettah (4-10 mg/kg) were relatively low compared to concentrations

measured in 19 other lakes near Yellowknife.

• GNWT sediment criteria developed for the boat launch, is 150 ug/g.
• Considerably higher concentrations of arsenic were noted in deeper sediments at

both locations—from the 40’s and 50’s (averaging ~700 mg/kg) with two peaks noted at depth.

• Water
• Water chemistry arsenic concentration ranges were as follows:

– Dettah: unfiltered: 0.4-1.3 ug/L; filtered: 0.4-1.3 ug/L; total recoverable As: 0.38- 1.38 ug/L; and – Ndilo: unfiltered: 2.0-2.3 ug/L; filtered: 1.8-2.1 ug/L; total recoverable As: 2.33- 2.71 ug/L.

• The study will continue in 2015/16, with an objective of filling information gaps

identified in the 2014/2015 study.

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Baseline Aquatics & Fisheries Studies in Gar Lake, Trapper Lake, Upper Shot Lake and Lower Shot Lake

• Aquatic and fisheries data were collected in September

2014 in the four study lakes.

– Aquatic program included field collection of biota. – Fisheries program included lake habitat characterization, fish presence, and community composition.

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Baseline Aquatic Habitat in Trapper Lake

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Baseline Aquatics & Fisheries Studies in Gar Lake, Trapper Lake, Upper Shot Lake and Lower Shot Lake Results for 2014/2015

• Arsenic concentrations

– Highest in Trapper Lake (up to 0.235 mg/L, 47 times the guideline) and Gar Lake (up to 0.136 mg/L, 27 times the guideline) – Lowest in Upper Shot Creek (up to 0.012 mg/L, just over two times the guideline) and Lower Shot Creek (up to 0.009 mg/L, slightly less than two times the guideline).

• Benthic invertebrate communities were similar in all four lakes.

Mayflies, generally considered to be pollution sensitive, were present in all four lakes.

• No fish were captured or observed in any lakes during the study.

– Fish habitat assessments in all four lakes indicated a lack of adequate habitat to support fish (ie: shallow water that may freeze to bottom on winter).

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Baseline Work in Terrestrial Environments

• Completed terrestrial baseline studies:

– Site Runoff & Storm Event Surface Water Quality Sampling Program (to update arsenic loading estimates to downstream aquatic receptors) – Pre- and Post-Roaster Deconstruction Breeding Bird Surveys – Site-Wide Bird Surveys – Site-Wide Bird Habitat Mapping Study – Site-Wide Contaminated Soils Assessment – Site-Wide Baseline Noise Assessment

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Site Runoff & Storm Event Surface Water Quality Sampling Program

• Purpose was:

– To provide a better understanding of potential As loading into Baker Creek and Back Bay from the Giant; and – To develop a better understanding of surface water flow into these two water bodies.

• Collection of water samples from 38 (of 43 proposed)

locations in Baker Creek and Yellowknife Bay watersheds included As speciation analysis, trace metals analysis (including total As), and routine chemistry parameters.

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Site Runoff & Storm Event Surface Water Quality Sampling Program

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Site Runoff & Storm Event Surface Water Quality Sampling Program Results for 2014/2015

• Concentrations of total arsenic exceeded CCME Water

Quality Guideline of 0.005 mg/L in all water samples collected during both sampling events.

– Water chemistry total arsenic concentrations ranged from 0.00503 mg/L to 4.56 mg/L. – However, majority of these total arsenic concentrations consist

• f As (V) (0.0021 to 4.53 mg/L) – less toxic forms.

– Only approximately 1% by volume of As (III) was present in each

• f these samples (0.000443 to 0.122 mg/L).
• Results may be abnormal as last year was very dry.

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Site Runoff & Storm Event Surface Water Quality Sampling Program Plan for 2015/2016

• The proposed 2015 site runoff sampling program will

augment the work performed in 2014 and will be focused

• n the Baker Creek watershed, as well as various runoff

channels into Back Bay (at Yellowknife Bay on Great Slave Lake).

– New sample locations added to the north and along YK Bay to fill a few gaps noted last year. – Our initial sampling episode was completed during freshet (May 2015).

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Site-Wide Bird Survey & Habitat Mapping Study

– Document bird use of infrastructure at the Site; – Assess risks to birds from remediation activities and existing infrastructure; and – Recommend mitigations to reduce identified risks and support compliance and due diligence to environmental protection legislation relevant to birds that are likely to

• ccur at the Site.

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Bird Habitat Mapping

• Bird habitats at the Site have been categorized into four

types:

– Uplands; – Wetlands (including open water); – Riparian areas; and – Disturbed areas.

• Each of these habitat types described in detail regarding

vegetation types present, geological formations, and resident bird species

– inform project site activities.

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Site-Wide Bird Survey & Habitat Mapping Study

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Site-Wide Bird Survey & Habitat Mapping Study Results for 2014/2015

• Few birds were detected because the survey was

conducted in fall.

– Eleven federally-listed species at risk have the potential to occur

• n site.

– Barn swallow and horned grebe were the only species detected and confirmed to breed on site during past surveys. – Barn swallows nest on habitats that are well represented across the site and any abandoned mine structures could be used for nesting.

• A few potential risks to birds on-site were identified

which will need to be addressed on a case by case basis.

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Site-Wide Bird Survey & Habitat Mapping Study Plan for 2015/2016

• The 2015/2016 surveys are intended to document bird

use of all active areas at the Site to inform the development of mitigations to reduce the risk to birds, their eggs and nests from industrial activities.

• The primary focus of this work will be areas of the site

where work is planned or ongoing for the 2015/2016 fiscal year field season—field work has now been completed.

• Site workers will be able to stay away from the few active

nests noted until young have fledged.

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Assessment of Regional Soil Quality

• The purpose of the regional soil sampling program was to

characterize the distribution of arsenic in shallow soils across the undeveloped areas of the Site.

– The results of this program will provide key data for a future risk assessment and inform discussion regarding end land use and project design.

• The program involved sampling vertical profiles at 103 locations

across the Site with the collection of 354 soil samples in the undisturbed areas.

– All samples were analyzed for bulk chemistry (ie metals). – The results of the bulk chemistry analysis were used to select a subset of 50 samples for arsenic speciation testing (completed by Queen’s University, Heather Jamieson group).

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Assessment of Regional Soil Quality – Sample Locations by Terrain Type

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Assessment of Regional Soil Quality Results for 2014/2015 – Sample Locations and Terrain Types

• Shallow soil across the Site has been impacted by two primary

mining-related anthropogenic sources

– former Roaster Stack emissions, and; – dust from mine rock and tailings.

• The highest concentrations of arsenic were recorded in shallow soil,

and these concentrations decreased quickly with depth.

• Overall decrease in concentrations of arsenic with increasing

distance from the former Roaster Stack

– secondary source from the tailings areas also confirmed.

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Assessment of Regional Soil Quality Results for 2014/2015 – Arsenic Speciation

• Arsenic speciation results provide mineralogical

evidence of the presence of three primary mining-related constituents in shallow soil:

– arsenic trioxide; – arsenopyrite; and – roaster oxides.

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Assessment of Regional Soil Quality – 2014/15 Results in Undisturbed Areas

• Shallow Bedrock Outcrops

– High concentrations of arsenic present (shallow soil (20 – 17,000 ug/g), intermediate/deep soil: (14 – 3,400 ug/g)) – Impacted soils are shallow (typically less than 200mm in depth). – Primarily Arsenic trioxide

• Forest Areas

– Arsenic concentrations lower compared to outcrop terrain (shallow soil (<1.0 – 900 ug/g), intermediate/deep soil: (3.2 - 45ug/g)) – Consist of both arsenic trioxide and arsenopyrite.

• Wetlands

– Concentrations of arsenic were significantly lower in the wetland areas (shallow soil (<0.01 – 3.1 ug/g), intermediate/deep soil: (<0.01 – 0.073 ug/g)) – Arsenic trioxide was not dominant in the shallow soils.

• Note that the current GNWT soil remediation criteria for Industrial land use

is 340 ug/g

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Proposed 2015 Work Program

• LTEMP Implementation and Management
• ver multiple years including regulatory

programs discussed previously

– Plus a gap analysis to ensure baseline assessments and studies are complete

• Habitat and Vertebrate Studies

– address commitments related to the Developers Assessment Report (DAR), and Wildlife Management Plan requirements expected from the new (remediation plan) Water Licence.

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Proposed 2015 Work Program

• Baker Creek System Contaminated Sediment

Investigation and Delineation

• Supplemental Contaminated Soil Arsenic

Characterization Study

• Supplemental Arsenic Loading Study on

Baker Creek watershed and Back Bay.

• Community monitoring sediment and surface

water program (N’Dilo and Dettah).

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