A Risk Communications Approach to Risk Assessment

Transcription

1 A Risk Communications Approach to Risk Assessment Diana Del Bel Belluz Risk Wise Inc. John Shortreed Institute for Risk Research University of Waterloo

2 An Application of Quantitative Risk Assessment Risk Issue A proposal to accept wastes from out-of-province. What are the changes in risks associated with the transportation of wastes to Swan Hills? Project Transportation Risk Assessment for The Alberta Special Waste Management System (1994) Hazard traffic accident release of waste

3 The Risk Communication Approach "question and answer" format, i.e., What did Albertans want to know? 3-tiered approach An executive summary or short answer to the question. A complete answer to the question. A technical appendix or other document supporting the answer.

4 Rationale for using a question & answer format Determine what kind of risk information people want and in what form. Develop a checklist of the likely concerns and questions of the community, based on the concerns people have had in similar situations in which the agency has been involved.

5 QUESTIONS Question 1: Routes and Trucks on Routes a. What routes will be used? b. How many trucks will use each road section? c. What wastes will be transported on each road section? Question 2: Accident Frequency What impact will the proposal have on the number of accidents for individual road sections? on the Province as a whole? Question 3: Losses Due to Accidents What impact (injuries and fatalities-, property loss; disruption; etc.) win the change in accident probability have on individual road sections? on the Province as a.whole? Question 4: Probability of Releases What will be the change in the number of releases of waste (with or without a traffic accident) for individual road sections? for the Province as a whole?

6 QUESTIONS Question 5: Consequences of Releases What are the consequences of releases for individual road sections? for the Province as a whole? Where are the most vulnerable locations? Question 6: Emergency Response Will changes in emergency response capabilities be required for specific route locations? Question 7: Transportation Management & Safety Controls How will the proposal affect existing transportation safety controls (for driver fatigue, vehicle maintenance, stops, load security, weather, etc.)?

7 QUESTIONS Question 8: Regulations/Safety Requirements What are the Federal and Provincial regulations? How are they implemented? Should any new regulations and controls be considered (training, enforcement, etc.)? Do any highways need upgrading due to the proposal? Question 9: Liability What is the maximum liability due to transport of wastes? How is it financed? Question 10: Other Questions Other questions to be identified at public meetings.

8 Rationale for using a 3-tiered approach People are at different stages on the continuum of understanding. Many citizens will say they want to know everything. Others simply want to know the bottom line: safe or not safe. It is important to provide an "interpretive, simple overview'. (Put the data in perspective) But, also make more technical information available to those who want to know more. (Express risks in several difference ways, making sure not to evade the risk question, i.e., Quantities, Concentrations, Exposures, Probabilities, Risk Levels)

9 Question 1: Routes and Trucks on Routes a. What routes will be used? b. How many trucks will use each road section? c. What wastes will be transported on each road section?

10 TIER 1 Each of the 3 sub-questions were answered in 1-page of text, or less! The text explained the methodology and the results TIER 2 Supporting tables and figures were used to supplement the text for readers who wanted more detail

11 Q1a. What routes will be utilized as principal and secondary routes? Transport Routes, Waste Origins, and Zones

12 Q1b. How many trucks will use each road section? Start with volume of waste for: Existing market (Alberta only) Amount approved under previous Environmental Impact Assessment Year 2000 estimate with both internal and external sources of waste Use sample of 100 to convert tonnes of waste to trucks per month Plot results on map of Province

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15 Estimated year 2000 number of loaded trucks per month on provincial highways.

16 Q1c. What wastes will be transported on each road section? Start with volume of waste for: Existing market (Alberta only) Amount approved under previous Environmental Impact Assessment Year 2000 estimate with both internal and external sources of waste Use sample of 100 to estimate proportions by type of waste and type of truck

17 Waste flows categorized into IRR classes TDG Miscellaneous 9* Flammable 3*, 4* Poison/ Toxic 6* Oxidizing/ Corrosive 5*, 8* PCB 9.2* Drums Class 1 e.g. gas plant filters/ reclaimed sludge & water Class 2 e.g. waste paint/ enamel / lacquers Class 3 e.g. household wastes/ antifreeze Class 4 e.g. spent sulphuric acid / detergent solution Class 5 e.g. PCB filled capacitors (17%) Tanker Class 6 e.g. paint solvent washings (10%) Class 7 e.g. nonchlorinated solvent (5%) Class 8 e.g. waste wash water (2%) Class 9 e.g. spent sulphuric acid (7%) Class 10 e.g. PCB oil/ groundwater (14%) (6%) (1%) (5%) (15%) Bulk Class 11 e.g. incinerator ash Class 12 Class 13 e.g. asbestos debris Class 14 Class 15 e.g. PCB contam. soil (2%) (0%) (3%) (0%) (12%)

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20 TIER 3 was contained in a 12-page appendix detailing the calculation steps for Question 1 Sampling and analysis of existing truck loads of waste. Estimation of tonnes of waste per truck. Estimation of existing market and origins and validation of truck- kilometers on the road network. Define the EIA Market in terms of IRR classes. Convert EIA Market into trucks on road sections. Define the Year 2000 Market in terms of IRR classes. Convert Year 2000 Market into trucks on road sections.

21 Did it work? Response of reviewers Response of readers Public Transport Canada Response of Natural Resources Conservation Board

22 Summary Address the issues and concerns of the audience Present information in a format that meets their information needs People are at different stages on the continuum of understanding. Provide an "interpretive, simple overview'. (Put the data in perspective) Make complete technical information available to those who want to know more. Express risks in several difference ways, making sure not to evade the risk question, i.e., Quantities, Concentrations, Exposures, Probabilities, Risk Levels