Impact Assessment 2 ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 84 What is Impact Assessment? ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 85 1What is Impact Assessment? •Attempt to describe the environmental consequence of the activity being studied – Accomplished by translating inventory into consequence (impact) ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 86 Why Impact Assessment? ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 87 2Why Impact Assessment? •Reduces number of data points against which to make a decision – If taken to single score, then complementary with decision theory – Monetized methods may be comparable with other metrics •Adds information – Provides input from a range of sciences and other stakeholders ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 88 What is Impact Assessment? ISO Definition • Impact Category Definition – Identify what impacts are of concern and which models will be used to translate inventory to impact • Classification: – Environmental stressors are correlated with specific impact categories • Characterization – Quantify amount of impact – Damage assessment • Aggregate similar impacts • Normalization • Valuation – Possibly weighting impacts to rank or aggregate ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 89 3Your thoughts: What do you see as the key issues? What is most challenging step? ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 91 Issue 1: Relevance •Translating from inventory to impact is – Introduces numerous assumptions • What are examples of assumptions? – Controversial – Necessity depends on context • Expertise / influence of decision-makers may influence the extent of aggregation required • ISO excludes weighting / valuation from comparisons for external distribution ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 92 4Issue 2: Translating Environmental Impact •The impact of pollution is rarely a simple one – C02 Æ Increases thermal absorption Æ Raises Temperature •So what? – Increased temperature Æ •Ice melting • Desertification •… •Assessment method, must take into account causal chain ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 93 Which Environmental Impacts should we care about? ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 94 5Issue 3: What Effects to Track? • ISO establishes three broad categories of concern – Resource use – Human health – Ecological consequence – There is debate over whether to include damage to the man-made environment (e.g., acid rain damage to ancient structures) • What about aesthetics? Comfort? • Key issue: Double counting – Boundary between categories is fuzzy • Oil depletion vs. Emissions from oil use ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 95 Impact Categories: Many differing approaches • Nordic Guidelines • Environmental priorities system – Resource depletion •Energy & material •Water •Land use – Human health • Toxicological • Non-toxicological • Work/living environment – Ecological •Global warming • Photochemical oxidation •Acidification • Ozone depletion • Eutrophication • Ecotoxicological • Bio-diversity – Human health – Biological diversity – Ecosystem production capacity (crops…) – Abiotic resources (metals…) – Cultural & recreational value (e.g., aesthetics…) ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 96 6Example Method 2: Eco-Indicator • Commissioned by Dutch Ministry of Housing, Spatial Planning, and the Environment to support goals of Integrated Product Policy • Aimed particularly at influencing design practice – Extensive documentation for product designers • Fundamental basis / Weighting factor: – Original (95): •Impact oriented • Based on distance to target – Current (99) • Damage oriented • Expert panel / differing perspectives • Generally represents impacts based on average conditions in Europe ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 100 Characterization • Expresses relative contribution of specific impact to the category of impact – E.g., Impact of CO2 release = 1 Impact of methane release = 21 • Mid point vs end-point – Increase in acidification vs. Increase in species depletion – Impact indicator vs. damage indicator – Less uncertainty vs. easier to value – Eco-indicator 99 is an endpoint / damage-based method – Eco-indicator 95 was a midpoint based method ESD.123/3.560: Industrial Ecology – Systems Perspectives Massachusetts Institute of Technology Randolph Kirchain Department of Materials Science & Engineering LCA: Slide 101 7Characterization: Eco-Indicator Damage Model • Fate – Where does the emission end up •Water soluble Æ likely in water supply • Insoluble Æ soil – How durable is the emission • Some substances