MA MANA NAGEMEN GEMENT T AND ND MO MONI NITORING ORING PL - - PowerPoint PPT Presentation

MVLWB Technical Session Snap Lake Mine Final Closure, and Water Licence and Land Permit Renewal July 16 to 18, 2019

MA MANA NAGEMEN GEMENT T AND ND MO MONI NITORING ORING PL PLANS NS

PUBLIC LIC PRESEN ENTATION ION

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• Main plans with highlights of changes
• Review of changes in:
• Air Quality, Waste, and Water
• New plan:
• Re-vegetation

OUTL TLINE

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KEY CHANGES GES/UPD /UPDATE TES

Manag ageme ement nt Plan Key Updates Engagement Plan Formatting, general updates to align with closure and post-closure activities Spill Contingency Plan Formatting, general updates to align with closure and post-closure activities; further updates will include contact information Emergency Response Plan Formatting, general updates to align with closure and post-closure activities Wildlife Monitoring Plan Wildli ldlife fe surveys during ing periods of occup upanc ancy, cessat ation ion of sensory distur urban ance monit itor

• ring

ing program ams and regio iona nal l monit itorin ing, formatting, general updates to align with closure and post-closure activities Vegetation Monitoring Plan Vegetation dustfall 5 years post-closure, footprint measures once/5 years, triggered dustfall effects studies. North Pile Management Plan Updated clos

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ure desig ign n descriptio ions ns includ luding ing cover and passive treatment ent system, em, updat ated closur ure and post- closure geotech ech monit itoring ing plan, formatting, general updates to align with closure and post-closure activities Air Quality and Emissions Monitoring and Management Plan PM2.5 monit itored during ing periods of occupa upanc ncy at station n located ed at commun unic ications ions build ilding ng, dust monit itored on- site, dustfal fall monit itorin ing g repeated 5 years post-clo losur ure, formatting, general updates to align with closure and post- closure activities Waste Management Plan Details ails of land ndfill fill operatio ions ns, formatting, general updates to align with closure and post-closure activities Water Management Plan Updated water balanc lance, e, water manag nageme ement nt system em components nents includ udin ing g north h pile perimeter water er control

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struc uctur ures, es, influent fluent storag age ponds, construc ucted wetland lands, SNP, formatting and general updates. Re-vegetation Plan New plan to describe revegetation of the disturbed Upland areas

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1.Air Quality will continue to be monitored during Closure and Post-Closure (see Table 7-1) CLOSURE:

• On-site dustfall to be monitored 6 times/year
• PM2.5 to be monitored continuously during periods of occupancy
• Meteorological monitoring during periods of occupancy
• Triggered: Additional dustfall effects surveys if triggered by exceedance of guidelines for 3 months or visible dusting of vegetation

POST-CLOSURE:

• Off-site vegetation dustfall once 5 years post closure (Vegetation species composition, cover and vigor, fixed and total dustfall, metals content of

dust, soil chemical and physical properties)

• 2. The AQEMMP is a requirement of the Environmental Agreement and has been reviewed as per the Agreement
• Draft submitted (February 1, 2019) ; Comments received (February 28, 2019) ; Responses provided (March 8, 2019); Final AQEMMP provided for

MVLWB registry (May 20, 2019)

• Included the Air Dispersion modelling for final closure. Conclusion – AQ will remain below NWT standards and plume dispersion limited to the RSA
• 3. The FCRP includes reference to the closure and post-closure monitoring of dust (SW1 – dust levels are safe)

AIR R QUALI ALITY AND EMISSIO SIONS MONITOR ORING G AND MANAGEMEN GEMENT T PLAN V.3

Revie iewe wer Concern erns

• ECCC-9; MVLWB-93; MVLWB-190: provide/identify the AQ monitoring plan
• MVLWB-69: add post-closure monitoring to FCRP Table 5.2
• SLEMA-13: dust should be measured post-closure

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AIR R QUALI ALITY AND EMISSIO SIONS MONITOR ORING G AND MANAGEMEN GEMENT T PLAN V.3

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WASTE TE MANAGE GEMENT ENT PLAN V4

Revie iewe wer Concern erns:

• GNWT-Lands-16: waste inventory
• GNWT-ENR-109: clarify types and quantities of landfill waste
• MVLWB-172: how were waste volumes calculated
• SLEMA-10: include landfarm in list of waste management facilities
• 1. FCRP (Sectio

ion n 5.3.)

• overview of waste

management

• 2. FCRP Appendix

ix G Demolit lition ion Invent ntor

• rie

ies and d Site Closur ure Plans ns

• volume estimates
• 3. FCRP Appendix

ix H North h Pile Closur ure Design ign

• landfill design,

monitoring, cover

• 4. Waste

e Manag ageme ement nt Plan

• Updated to align with

closure and post-closure Closure landfill Operational landfill Historic landfill Landfarm Potential Future landfarm

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WASTE TE MANAGE GEMENT ENT PLAN V4 (LANDFIL DFILL AREAS S –PLAN VIEW)

Landfill Waste sequencing landfill capacity: ~114,000 m3 East Cell deposited PK:

• Excavate Cell 2
• Place PK in Cell 3

East Cell waste placement:

• Cell 1 (existing

landfill)

• Cell 2

Landfill areas

Cell 1 Cell 2 Cell LF

Reviewe wer comment nts:

• GWNT-Lands 3 – map showing the location of the landfill

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• Upland Revegetation (Appendix J):
• Criteria were clarified to include both completion of the reclamation activities (scarification, soil prep, seeding) and a

measure of performance (5% mean plant coverage within 5 years of seeding resulting in 29.5% plant coverage over the LSA)

• Monitoring will occur annually during first 5 years and include soil sampling and vegetation growth monitoring. If criteria are

not met, monitoring will continue

• Re-vegetation techniques
• i. Passive – Leave as constructed and natural encroachment of vegetation
• lightly disturbed areas, natural recovery already underway, access limited
• ii. Active-FS – Scarification with native seed and fertilizer applied to the disturbed surface
• Site roads, airstrip and other remaining upland areas
• iii. Active-OFS – Scarification with overburden placement and native seed and fertilizer applied to the disturbed surface
• Mine Building Area

RE RE-VEGET EGETATION TION PLAN (APPE PENDI DIX X J)

Reviewe wer comment nts:

• MVLWB 177 – how will the airstrip be revegetated?
• GNWT ENR 161 – clarify timelines because Phase II ESA may be influence revegetation.
• GNWT ENR 169 – recommend annual monitoring during active remediation
• MVLWB 112 – how do you measure successful completion of promotion of natural recovery?

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REVEGE EGETATION ON PLAN – AREAS S

Active OFS Passive Active FS

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• The plan describes activities related to water management
• The purpose is to collect, contain, and control the release of water
• Water management has changed significantly and has been greatly simplified (as compared to Operations)
• Includes the surveillance network program (SNP)
• The objective of the SNP is to detail sampling and monitoring requirements related to conditions and required by the

Licence

• The current water licence has 36 stations, 6 are inactive and 30 active
• For the next water licence, De Beers is recommending to:
• Add stations (6); or
• Retain stations (7); or
• Eliminate stations (29).
• Closure and Post-Closure SNP is focused on intakes, discharges, and the receiving environment

WATER ER MANAGEMEN GEMENT T PLAN V4

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• SNP stations were reviewed for relevance and are focused on key downstream locations that can be

maintained over the long term, and that will capture potential changes in the upstream environment, such as chemical changes in the seepage.

• The monitoring data at the SNP stations has been submitted monthly throughout operations.
• Figures showing visual trends for on-site SNP stations that support recommendations regarding changes to

the SNP program are provided in the ARD and Geochemical Annual Report

• A robust set of SNP stations to monitor water at Snap Lake Mine has been proposed

WATER ER MANAGEMEN GEMENT T PLAN V4 (SUR URVEI EILLANCE E NETWOR ORK PROGRAM GRAM)

Reviewe wer comment nts:

• GNWT ENR 49: clarification regarding footnotes
• GWNT ENR 50: recommends additional SNP stations to be located as required to monitor surface run-off
• GNWT ENR 55: requesting summary report of monitoring results at SNP stations
• GNWT ENR 66: recommends adding SNP locations on Figure in EQC report
• GNWT ENR 70, 165: requests rationale for number of SNP stations and duration of monitoring in SL
• GNWT-ENR #51, 52, 53, 55, 56, 57, 58, 59, 60, 61, 62, 63 : on-site SNP trends