Life Cycle Assessment of Brownfield Management P. Lesage, L. Deschênes, R. Samson CIRAIG – Interuniversity Reference Center for the Life Cycle Analysis, Interpretation and Management of Products, Processes and Services NSERC Industrial Chair in Site Remediation and Management Dept. of Chemical Engineering École Polytechnique de Montréal

The brownfield problem What is a brownfield? –Site whose expansion, redevelopment, or reuse is complicated by a real or perceived contamination (US EPA) –Necessitates an intervention Widespread in industrial countries –Canada – At least sites –USA – to sites

Example (case study) 50 ha Montreal brownfield Heavy industrial activity (railway company’s shops) Mixed and persistent soil and groundwater contamination (metal, PAH, PHC, sulphur), slag

Impacts of brownfields Economic –Loss of economic opportunity –Devaluation of surrounding land –Encouragement of urban sprawl –Loss of tax base Environmental –IF site contaminated, human health and ecological risk –Encouragement of urban sprawl (land competition) Low density land occupation, car dependence, etc. Social –Adverse impact on neighbourhood image –Eyesore –Higher crime rate –Worsens inner-city deterioration

Overview of presentation Brownfields and the urban site life cycle Presentation of the urban site life cycle Environmental aspects Brownfield management Two functions Environmental assessment LCA of brownfield management Existing approaches Single-site application Multiple-site application

Urban site life cycle Greenfield Transformation Occupation/ Exploitation Occupation end

Possible legacy Infrastructure (maybe decrepit) –Standing –Underground Presence of onsite contamination –Soil –Groundwater Land derelict –land so damaged by development that it is incapable of beneficial use without treatment

Sites not requiring intervention Greenfield Transformation Occupation/ Exploitation No No action Occupation end

Sites requiring intervention Brownfields: Intervention needed for reuse Greenfield Transformation Occupation/ Exploitation Intervention Yes Brownfield No action Occupation end

Case study – Brownfield rehabilitation and redevelopment Intervention –Dig & haul –Onsite containment –Cover –Material recycling Transformation and exploitation –Industrial park –1250 residences –Commercial area –Green spaces

Environmental aspects Primary impacts: –Impacts associated with the state of the site Secondary impacts –Impacts associated with intervention on a brownfield Tertiary impacts –Impacts on regional land use resulting from brownfield management decisions

Primary impacts Impacts associated with the state of the site –Life support functions –Biodiversity –Risk (if site contaminated) t 1 t 3 t 2 Environmental quality (EQ) Time 1 Greenfield No action Brownfield 2 RedevelopmentIntervention Brownfield 3 GreenfieldBrownfield Intervention

Secondary impacts Impacts associated with intervention on a brownfield –Local impacts of intervention (noise, dust, etc.) –Long-term fate of managed contaminants –Life cycle impacts of intervention

Tertiary impacts Impacts on regional land use resulting from brownfield management decisions –Reintegrating brownfields in economy counters urban sprawl –Land transformation differential –Differential impacts of urban and periurban land occupation

Overview of presentation Brownfields and the urban site life cycle Presentation of the urban site life cycle Environmental aspects Brownfield management Two functions Environmental assessment LCA of brownfield management Existing approaches Single-site application Multiple-site application

Two functions of brownfield management Function 1: Risk management –For contaminated brownfields –Lower human and ecosystem risk to acceptable levels Function 2: Brownfield redevelopment –Prevention of urban sprawl/“Smart growth” –Socioeconomic benefits

Environmental decision support Primary impacts: –Many tools for risk assessment and management Secondary impacts –LCA-based tools for life cycle impacts of intervention Tertiary impacts –General conclusions assumed valid, often no case-specific evaluations No tool for treating all environmental issues under one consistent framework (except possibly MCA)

Overview of presentation Brownfields and the urban site life cycle Presentation of the urban site life cycle Environmental aspects Brownfield management Two functions Environmental assessment LCA of brownfield management Existing approaches Single-site application Multiple-site application

Limitations of existing LCA in the field Limited to risk management function –Focus on how to go about the intervention phase –Technology comparison Primary impacts excluded Long-term fate of contaminants excluded Tertiary impacts excluded Land use impact category not fully exploited

Life cycle of intervention for case study

Proposal LCA can provide the framework to consider: –Both functions (risk management, redevelopment) –Whole iterations of the urban site life cycle –Three classes of impacts Method – system expansion Current research project restricted to residential reuse of site

Multi-functional FU Two functions in functional unit: –Manage risk within constraints of policy on contaminated site –Develop and occupy x residential units for t years

2 options to meet functions Option 2 Option 1 Decontamination (1ha) & redevelopment (1ha) Restrictive measures (1ha) & greenfield development (>1ha)

Single site application Decision support for what should be done with a given brownfield Stakeholders: Site owners, municipality and other approving bodies, lenders “Urban sprawl”“Smart growth”Tertiary NoneHigh impactsSecondary No improvement ImprovementPrimary Option 2Option 1Impacts

LCI modeling issues Onsite contaminants –Brownfield considered in ecosphere –Fate model Long-term fate of managed contaminants –Leaching from landfills and containment cells Tertiary impacts –Differential land use and infrastructure from statistical data –Differential use of residences function of time Marginal modeling –E.g. Transportation 1 Delay Situation Volume/capacity

Multiple site application Determine impacts of applying the decision to all brownfields of Montreal Stakeholders: municipal and national government Same two options compared

LCI modeling issues Decontamination technology mix Scale of change calls for modeling scenarios –New road construction for increased transportation –Landfill capacity a major issue Scaled to the same reference flow(s)

Other possible applications of framework Prioritizing sites for intervention Comparisons of different types of redevelopment (commercial, industrial) Evaluating impacts of contaminated site legislation Evaluation of the externalities of management options – correct the market failure

Conclusion Brownfield management is an environmentally complex issue –Primary, secondary and tertiary impacts LCA so far limited to secondary (and sometimes primary) impacts LCA can give a holistic perspective on environmental impacts of brownfield management by considering the site’s whole life cycle.