Case Study: Installing Landfill Case Study: Installing Landfill Gas Controls Within a Gas Controls Within a

Redeveloped Inactive LandfillRedeveloped Inactive Landfill

B. Marc Adams Martin OrtizB. Marc Adams Martin Ortiz

•• EBA Engineering ConsultantsEBA Engineering Consultants

•• Province of AlbertaProvince of Alberta

•• Calgary Zoological SocietyCalgary Zoological Society

AcknowledgementsAcknowledgementsAcknowledgements

• Site and Project Background

• Conceptual Site Model

• LFG Controls – Selection and Design

• LFG Controls – Implementation

• Conclusions

•• Site and Project BackgroundSite and Project Background

•• Conceptual Site ModelConceptual Site Model

•• LFG Controls LFG Controls –– Selection and DesignSelection and Design

•• LFG Controls LFG Controls –– ImplementationImplementation

•• ConclusionsConclusions

Presentation OutlinePresentation OutlinePresentation Outline

BackgroundBackgroundBackground

Deerfoot Trail

Memorial Drive

Calgary Zoo

Bow River

MaylandCommercial/IndustrialArea

TomCampbell’sHill

Nose C

reekMayland Heights

Renfrew&Bridgeland/Riverside

Bottom-landsPark

NewScience CentreNose HillNose Hill

GlenmoreReservoirGlenmoreReservoir

BowRiverBowRiver

DowntownDowntown

City of CalgaryCity of CalgaryCity of Calgary

Nose CreekNose Creek

West Nose CreekWest Nose Creek

Site LocationSite LocationSite Location

Zoo NorthParkingLot

Nose Creek Nose Creek Landfill HistoryLandfill History

Area 2/2A

• Landfilling from as early as 1914 to early 1980s– Facility closed in 1967– Early activity and post-

1967 activity lacks documentation

• Oxbows, stream channel, valley ravines, general low lying areas were filled

• Deposits of household and construction waste

•• Landfilling from as early Landfilling from as early as 1914 to early 1980sas 1914 to early 1980s–– Facility closed in 1967Facility closed in 1967–– Early activity and postEarly activity and post--

1967 activity lacks 1967 activity lacks documentationdocumentation

•• Oxbows, stream channel, Oxbows, stream channel, valley ravines, general valley ravines, general low lying areas were low lying areas were filledfilled

•• Deposits of household Deposits of household and construction wasteand construction waste

City of Calgary 2010

Landfill Area 2/2ALandfill Area 2/2ALandfill Area 2/2A

• Environmental investigations undertaken from early-1990s – (and ongoing)

• ~40 investigation locations across Area 2/2A– 35 monitoring wells at 19

locations, 10 vapour probes

• Studying• Landfill Waste• Soil• Soil vapour / landfill gas• Groundwater• Surface water• GW / SW interaction

•• Environmental investigations Environmental investigations undertaken from earlyundertaken from early--1990s 1990s –– (and ongoing)(and ongoing)

•• ~40 investigation locations ~40 investigation locations across Area 2/2Aacross Area 2/2A–– 35 monitoring wells at 19 35 monitoring wells at 19

locations, 10 vapour probeslocations, 10 vapour probes

•• StudyingStudying•• Landfill WasteLandfill Waste•• SoilSoil•• Soil vapour / landfill gasSoil vapour / landfill gas•• GroundwaterGroundwater•• Surface waterSurface water•• GW / SW interactionGW / SW interaction

Area 2/2A

Risk AssessmentsRisk AssessmentsRisk Assessments

• Ecological and human health risk assessments conducted for Area 2/2A– Evaluating soil, groundwater,

surface water and soil vapour conditions

– Based on current land use and current surface water conditions

– Physical hazard from methane component of landfill gas not considered

•• Ecological and human health Ecological and human health risk assessments conducted risk assessments conducted for Area 2/2Afor Area 2/2A–– Evaluating soil, groundwater, Evaluating soil, groundwater,

surface water and soil vapour surface water and soil vapour conditionsconditions

–– Based on current land use and Based on current land use and current surface water current surface water conditionsconditions

–– Physical hazard from methane Physical hazard from methane component of landfill gas not component of landfill gas not consideredconsidered

Area 2/2A

Conceptual Site Model / Environmental Management

Plan

Conceptual Site Model / Conceptual Site Model / Environmental Management Environmental Management

PlanPlan

Environmental Management PlanEnvironmental Management PlanEnvironmental Management Plan

• Comprehensive plan being developed– Active exposure scenarios

identified– Maintenance of inactive

exposure scenarios– Mitigation of active exposure

scenarios– Contingency plans

• LFG controls planned for Area 2/2A

•• Comprehensive plan being Comprehensive plan being developeddeveloped–– Active exposure scenarios Active exposure scenarios

identifiedidentified–– Maintenance of inactive Maintenance of inactive

exposure scenariosexposure scenarios–– Mitigation of active exposure Mitigation of active exposure

scenariosscenarios–– Contingency plansContingency plans

•• LFG controls planned for Area LFG controls planned for Area 2/2A2/2A

Recep

torPathway

Source(contaminant)

Deerfoot Trail

Memorial Drive

Bow River

TomCampbell’sHill

Nose C

reek

Bottom-landsPark

Calgary Zoo

Mayland Heights

NewScience Centre

MaylandCommercial/IndustrialArea

Renfrew&Bridgeland/Riverside

Zoo NorthParkingLot

Conceptual Site ModelConceptual Site ModelConceptual Site Model• Exposure scenarios

– Intersection of source, pathway and receptor– Soil contact, surface water contact/ingestion (incl. subsurface

soil/waste leaching to groundwater), groundwater contact/ ingestion, soil vapour inhalation

•• Exposure scenariosExposure scenarios–– Intersection of source, pathway and receptorIntersection of source, pathway and receptor–– Soil contact, surface water contact/ingestion (incl. subsurface Soil contact, surface water contact/ingestion (incl. subsurface

soil/waste leaching to groundwater), groundwater contact/ soil/waste leaching to groundwater), groundwater contact/ ingestion, soil vapour inhalationingestion, soil vapour inhalation

AMEC 2007

Landfill Gas ControlsLandfill Gas ControlsLandfill Gas Controls

• Impetus– Methane not fully considered in HHERA, elevated levels present in

areas of high activity– Vapour inhalation pathway exposure scenario potential concern in

future development

• Precautionary measures planned– Mitigate methane accumulations in subsurface– Prevent potential migration off site or into on-site enclosed spaces– Also beneficial to control of NMOC

•• ImpetusImpetus–– Methane not fully considered in HHERA, elevated levels present iMethane not fully considered in HHERA, elevated levels present in n

areas of high activityareas of high activity–– Vapour inhalation pathway exposure scenario potential concern inVapour inhalation pathway exposure scenario potential concern in

future developmentfuture development

•• Precautionary measures plannedPrecautionary measures planned–– Mitigate methane accumulations in subsurfaceMitigate methane accumulations in subsurface–– Prevent potential migration off site or into onPrevent potential migration off site or into on--site enclosed spacessite enclosed spaces–– Also beneficial to control of NMOCAlso beneficial to control of NMOC

LFG SourceLFG SourceLFG Source

• Municipal Sanitary Waste– Area 2/2A ~700,000 m3

• LFG Composition– Methane

• From ppmv range to ~70% CH4• Higher levels at south end

– NMOC• Volatile organic compounds• Hydrocarbons• Chlorinated solvents

– CO2, H2S• Elevated CO2, H2S relatively low

•• Municipal Sanitary WasteMunicipal Sanitary Waste–– Area 2/2A ~700,000 mArea 2/2A ~700,000 m33

•• LFG CompositionLFG Composition–– Methane Methane

•• From ppmv range to ~70% CH4From ppmv range to ~70% CH4•• Higher levels at south endHigher levels at south end

–– NMOCNMOC•• Volatile organic compoundsVolatile organic compounds•• HydrocarbonsHydrocarbons•• Chlorinated solventsChlorinated solvents

–– CO2, H2SCO2, H2S•• Elevated CO2, H2S relatively lowElevated CO2, H2S relatively low

LFG PathwaysLFG PathwaysLFG Pathways• Site Geology

– Fill soil (silt), waste (with soil), silt/sand, sands and gravels, bedrock

• Topography and ground cover– Ground highest in west, decreasing toward creek in east– Primarily asphalt cover, except landscaping islands and natural

vegetation around buildings in north, road and tunnel in south

•• Site GeologySite Geology–– Fill soil (silt), waste (with soil), silt/sand, sands and gravelFill soil (silt), waste (with soil), silt/sand, sands and gravels, bedrocks, bedrock

•• Topography and ground coverTopography and ground cover–– Ground highest in west, decreasing toward creek in eastGround highest in west, decreasing toward creek in east–– Primarily asphalt cover, except landscaping islands and natural Primarily asphalt cover, except landscaping islands and natural

vegetation around buildings in north, road and tunnel in southvegetation around buildings in north, road and tunnel in south

Landfill Deposits

Fill Soil

Native Soils

Bedrock

NoseCreek

LFG ReceptorsLFG ReceptorsLFG Receptors

• Indoor Environments and Enclosed Spaces– Maintenance shop and animal

hospital in north• Zoo workers

– Admissions facility and tunnels in south• Public access

– Storm sewers and utility manholes across site• Utility workers

• Outdoor spaces– Emission control

•• Indoor Environments and Indoor Environments and Enclosed SpacesEnclosed Spaces–– Maintenance shop and animal Maintenance shop and animal

hospital in northhospital in north•• Zoo workersZoo workers

–– Admissions facility and Admissions facility and tunnels in southtunnels in south•• Public accessPublic access

–– Storm sewers and utility Storm sewers and utility manholes across sitemanholes across site•• Utility workersUtility workers

•• Outdoor spacesOutdoor spaces–– Emission controlEmission control

Area 2/2A LFG Controls –Selection & Design

Area 2/2A LFG Controls Area 2/2A LFG Controls ––Selection & DesignSelection & Design

LFG Controls - ObjectivesLFG Controls LFG Controls -- ObjectivesObjectives

Precautionary measures

•Mitigate methane accumulations in subsurface

•Prevent potential migration off site or into on-site enclosed spaces

Precautionary measuresPrecautionary measures

••Mitigate methane accumulations in subsurfaceMitigate methane accumulations in subsurface

••Prevent potential migration off site or into onPrevent potential migration off site or into on--site enclosed spacessite enclosed spaces

Stakeholder ConsiderationsStakeholder ConsiderationsStakeholder Considerations

• Current leaseholder with significant existing development on lands

• Ongoing public access daily, throughout year and across the area

• Worker exposure

• System design must consider structures and infrastructure

• Installation activity must consider access restrictions• System selection must consider long term impact

•• Current leaseholder with significant existing Current leaseholder with significant existing development on landsdevelopment on lands

•• Ongoing public access daily, throughout year and Ongoing public access daily, throughout year and across the areaacross the area

•• Worker exposureWorker exposure

•• System design must consider structures and System design must consider structures and infrastructureinfrastructure

•• Installation activity must consider access restrictionsInstallation activity must consider access restrictions•• System selection must consider long term impactSystem selection must consider long term impact

Development OpportunityDevelopment Development OpportunityOpportunity

• Major redevelopment of parking lot in 2009

• Opportunity to coordinate installation

• Design testing• Coordinate design with parking

lot design and tendering• Coordinate installation with

parking lot construction

•• Major redevelopment of Major redevelopment of parking lot in 2009parking lot in 2009

•• Opportunity to coordinate Opportunity to coordinate installationinstallation

•• Design testingDesign testing•• Coordinate design with parking Coordinate design with parking

lot design and tenderinglot design and tendering•• Coordinate installation with Coordinate installation with

parking lot constructionparking lot construction

LFG Controls LayoutLFG Controls LFG Controls LayoutLayout

• Four headers installed• Horizontal extraction vents

on headers Aeast, Awest and B– Lower elevations, closer to

waste deposits

• Vertical extraction wells on header C– Higher elevation, deeper

waste deposits

• Perimeter control

•• Four headers installedFour headers installed•• Horizontal extraction vents Horizontal extraction vents

on headers Aon headers Aeasteast, A, Awestwest and Band B–– Lower elevations, closer to Lower elevations, closer to

waste depositswaste deposits

•• Vertical extraction wells on Vertical extraction wells on header Cheader C–– Higher elevation, deeper Higher elevation, deeper

waste depositswaste deposits

•• Perimeter controlPerimeter control

Project StagingProject StagingProject Staging

• Assessment of available site information• Focused testing to obtain design parameters• Preliminary design for parking lot tender docs

– Eastern vent spacing based on pilot tests– Central vent spacing based on redevelopment opportunity

• Header installation during parking lot redevelopment• Pilot extraction well installation and pilot testing• Vertical vent design & installation• Long term pilot test of piping network • Extraction treatment system design and installation

•• Assessment of available site informationAssessment of available site information•• Focused testing to obtain design parametersFocused testing to obtain design parameters•• Preliminary design for parking lot tender docsPreliminary design for parking lot tender docs

–– Eastern vent spacing based on pilot testsEastern vent spacing based on pilot tests–– Central vent spacing based on redevelopment opportunityCentral vent spacing based on redevelopment opportunity

•• Header installation during parking lot redevelopmentHeader installation during parking lot redevelopment•• Pilot extraction well installation and pilot testingPilot extraction well installation and pilot testing•• Vertical vent design & installationVertical vent design & installation•• Long term pilot test of piping network Long term pilot test of piping network •• Extraction treatment system design and installationExtraction treatment system design and installation

Project ImplementationProject ImplementationProject Implementation

CoordinationCoordinationCoordination

• Site access– Limitations due to site development – asphalt areas,

sidewalks, access roads, topography, buildings, utilities

• Coordination with land use– Daily, weekly and seasonal limitations

• Zoo parking lot redevelopment program– One time opportunity for enhanced site access– Required staged approach to design and installation

• Sanitary sewer trunk line upgrade– Followed piping installation, required protection during

program– Design considerations to sewer trunk line

•• Site accessSite access–– Limitations due to site development Limitations due to site development –– asphalt areas, asphalt areas,

sidewalks, access roads, topography, buildings, utilitiessidewalks, access roads, topography, buildings, utilities

•• Coordination with land useCoordination with land use–– Daily, weekly and seasonal limitationsDaily, weekly and seasonal limitations

•• Zoo parking lot redevelopment programZoo parking lot redevelopment program–– One time opportunity for enhanced site accessOne time opportunity for enhanced site access–– Required staged approach to design and installationRequired staged approach to design and installation

•• Sanitary sewer trunk line upgradeSanitary sewer trunk line upgrade–– Followed piping installation, required protection during Followed piping installation, required protection during

programprogram–– Design considerations to sewer trunk lineDesign considerations to sewer trunk line

InstallationInstallationInstallation

• Culvert installation• Header and vent installation

during parking lot redevelopment – Eastern vent spacing– Central vent spacing

• Vertical vent installation and tie in

• System fabrication and installation

•• Culvert installationCulvert installation•• Header and vent installation Header and vent installation

during parking lot during parking lot redevelopment redevelopment –– Eastern vent spacingEastern vent spacing–– Central vent spacingCentral vent spacing

•• Vertical vent installation and Vertical vent installation and tie intie in

•• System fabrication and System fabrication and installationinstallation

Header and Horizontal VentInstallation

Header and Horizontal VentHeader and Horizontal VentInstallationInstallation

• July – Nov. 2009•• July July –– Nov. 2009Nov. 2009

Vertical Extraction WellInstallation

Vertical Extraction WellVertical Extraction WellInstallationInstallation

• Dec. 2010 – Feb. 2011•• Dec. 2010 Dec. 2010 –– Feb. 2011Feb. 2011

Extended Pilot Test & System Design Extended Pilot Test & System Design Extended Pilot Test & System Design

• October-November 2011• Pilot Test Objectives

– Obtain flow data and area of influence for extraction design– Obtain long term LFG quality data for treatment design

• System Design– Emissions threshold definition– Stakeholder input – land use

considerations– Operational requirements

•• OctoberOctober--November 2011November 2011•• Pilot Test ObjectivesPilot Test Objectives

–– Obtain flow data and area of influence for extraction designObtain flow data and area of influence for extraction design–– Obtain long term LFG quality data for treatment designObtain long term LFG quality data for treatment design

•• System DesignSystem Design–– Emissions threshold definitionEmissions threshold definition–– Stakeholder input Stakeholder input –– land use land use

considerationsconsiderations–– Operational requirementsOperational requirements

System Fabrication/Installation System Fabrication/Installation System Fabrication/Installation

• Anticipated: January – March 2012• Commissioning: March 2012•• Anticipated: January Anticipated: January –– March 2012March 2012•• Commissioning: March 2012Commissioning: March 2012

ConclusionsConclusionsConclusions

• Successful installation of subsurface infrastructure across a large, active facility

• Staging of both design and construction allowed this installation without major disruption to the facility

• Involvement and cooperation of the land user was key to attaining success

• Retrofitting a redeveloped landfill is possible if flexibility and stakeholder engagement are strongly applied

• Premium costs of system retrofit can be avoided through opportunistic design and installation

•• Successful installation of subsurface infrastructure across a Successful installation of subsurface infrastructure across a large, active facilitylarge, active facility

•• StagingStaging of both design and construction allowed this of both design and construction allowed this installation without major disruption to the facilityinstallation without major disruption to the facility

•• Involvement and cooperation of the land user Involvement and cooperation of the land user was key to was key to attaining successattaining success

•• Retrofitting a redeveloped landfill is possible if flexibility Retrofitting a redeveloped landfill is possible if flexibility and stakeholder engagement are strongly appliedand stakeholder engagement are strongly applied

•• Premium costs of system retrofit can be avoided through Premium costs of system retrofit can be avoided through opportunistic design and installationopportunistic design and installation

Questions?Questions?Questions?

Area 2/2A

Nose Creek LandfillNose Creek LandfillArea 2/2AArea 2/2A