Phase A Aleutian Islands Risk Assessment. Options and Recommended Risk Matrix Approach. April 27, 2010

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1 Phase A Aleutian Islands Risk Assessment Options and Recommended Risk Matrix Approach April 27, 2010

2 Agenda for Risk Matrix Discussion Introductions Where we are in AIRA Phase A Risk Matrix Background Risk Matrix Design Options - Overview of options - Examples - Option details and discussion Recommended Approach Discussion and Agreement 2

3 Background Where We Are in AIRA Phase A Traffic Study Spill Baseline Study Identify High-Risk Accidents - Hazardous substances - Representative spill sizes - Locations of spills We are here Phase A Consequence Analysis Accident Scenario and Causality Study Phase A: Semi-qualitative study intended to provide a high-level understanding of relative risks taking into consideration types of vessels and hazardous substances, and the locations where discharges are most likely to occur -RFP 3

4 Background: Not in scope now, but later In the Phase B Focused Risk Assessment, the assessment approaches and techniques should be applied in more detailed, quantitative analyses. - SR293 p. 15 4

5 Background on Risk Matrix Risk Assessment Process - Generic - (IMO 2002 taken from SR293) Risk matrix - analysis / evaluation tool 5

6 Background on Risk Matrix Frequency of Occurrence/ Likelihood Frequent (A) Occasional (B) Seldom (C) Remote (D) Unlikely (E) Incidental (5) Low Risk Severity of Incident (or Consequence) Minor (4) Serious (3) Major (2) High Risk Catastrophic (1) 6

7 Background on Risk Matrix Uses and Limitations Visual display of likelihood and severity to allow - risk ranking - Identify greatest risks Quick analysis: qualitative or quantitative High level perspective Compare baseline vs. mitigated Must describe very undesirable conditions (the focus) Not good for cumulative risk Frequency of Occurrence/ Likelihood Frequent (A) Occasional (B) Seldom (C) Remote (D) Unlikely (E) Incidental (5) Low Risk Severity of Incident (or Consequence) Minor (4) Serious (3) Major (2) High Risk Catastrophic (1) Not good to identify causes given few data points Task 3 Goal: Identify the hazardous substances, representative spill sizes, and locations of spills associated with the highest-risk accidents. 7

8 How Risk Matrix is Used in AIRA Task 3 - Characterizing Spills from Highest Risk Accidents - Identify greatest risks (i.e., scenario selection) - Limited data for environmental impact Task 5 - Accident Scenario and Causality Study - Identify mitigation measures with greatest potential benefit - Detailed data for environmental impact A single matrix can meet the needs, with adjustments to column definitions 8

9 Risk Matrix Overview of Design Options 1.Matrix granularity 2.Define rows & columns 3.High risk cells 1. Matrix granularity 3x3 5x5 7x7 2. Define Rows & Columns Frequency need range definition Severity need range and column definitions Low Medium High 3. Which cells define high risk scenarios Only the red? Include the orange? Do we consider data in orange cells for Task 3? limiting: 20 scenarios modeled in Phase A Task 4 Frequency of Occurrence/ Likelihood Frequent (A) Occasional (B) Seldom (C) Remote (D) Unlikely (E) Incidental (5) Low Risk Severity of Incident (or Consequence) Minor (4) Serious (3) Major (2) High Risk Catastrophic (1) 9

10 1. How Many Boxes Should There Be? 1.Matrix granularity 2.Define rows & columns 3.High risk cells Option Pros Cons LowRisk 3x3 - Simple data mapping and output - Fewer cells to define 5x5 - Moderate complexity data mapping HighRisk - Commonly used - Moderate granularity - Recommended in SR 293 7x7 - High granularity - Better resolution for qualitative evaluation of a large number of options - Consistent with ISO Lack of differentiation if lots of data - Unclear scenario selection for modeling - Must define which cells provide input to scenario development - Moderate number of cells to define - High complexity data mapping - High number of cells to define - Number of high risk cells must be balanced with need for granularity. (May get same result as 5x5, with greater level of effort) 5x5 provides enough granularity without unnecessary complexity 10

11 2. Define Rows & Columns 1.Matrix granularity 2.Define rows & columns 3.High risk cells Requirements - Implementable version now (Task 3) and later (Task 5) - Data different now (Task 3) and later (Task 5) - Useful output now (Task 3) and later (Task 5) Frequency Options (rows): - Use pre-defined ranges (e.g., multiples of ten) to define rows 1x10-5 to 1x10-6 events/yr - Define range of actual data into equal spans of frequency (scale matrix to fit data) Severity Options (columns): - Use pre-defined ranges (e.g., multiples of 10 for volume) to define columns 1,000-10,000 gallons/event - Use greatest severity in actual data to define most severe column, and scale remaining columns equally (scale matrix to fit data) Development of matrix ranges based on data provides the best possible resolution 11

12 2. Define Rows & Columns 1.Matrix granularity 2.Define rows & columns 3.High risk cells Task 3 Characterizing Spills from Highest Risk Accidents - Identify greatest risks (i.e., scenario selection) - Limited data for environmental impact Quantitative volume, material spilled Qualitative location of release, location of receptors? Task 5 - Accident Scenario and Causality Study - Identify mitigation measures with greatest potential benefit - Detailed data for environmental impact Quantitative effect on receptors (volume, material, location of release and receptors) Severity definitions must differ for the two tasks 12

13 Example (Real-World) E Severity Criteria 1.Matrix granularity 2.Define rows & columns 3.High risk cells Effect/scale-focused Commitment-focused Volume-focused (material considered) Catastrophic permanent loss/extinction (100%) of species, habitat or ecosystem. Irrevocable loss, no mitigation possible. Major/Extended Duration/Full-Scale Response > bbl of oil in sensitive coastal waters > bbl of oil in other coastal waters Prolonged regional / global contamination Serious loss or migration (>50%) of species population, habitat or ecosystem. Partial mitigation only possible through prolonged and resource intensive effort (>50 years). Temporary, but reversible loss/migration of species population (<25%), habitat or ecosystem. Moderate mitigation efforts required for total reversal. Brief, but reversible loss/migration of species population (<15%), habitat or ecosystem. Minor mitigation efforts required for total reversal. Some minor loss/migration of species population (<10%) habitat or ecosystem that are short term and immediately and completely reversible. Serious/Significant Resource Commitment Moderate/Limited Response of Short Duration Minor/Little or No Response Needed > bbl of oil in sensitive coastal waters > bbl of oil in other coastal waters Short term damage at regional level Prolonged contamination requiring extensive nature conservation or monitoring/mitigation > bbl of oil in sensitive area >100 Te of classified material Long term damage affecting extensive area Uncontained release of reportable quantity (e.g. >100 bbl of oil, less if in sensitive location or >10 Te classified material) Extensive short term pollution / contamination Prolonged pollution / contamination affecting limited area Release offsite with immediate remediation or onsite release with prolonged damage Onsite release that is remediated immediately Contained onsite release 13

14 2. Defining Severity (columns) what data will we base severity on? Task 3 Options - Effect/scale of consequence - Commitment required after the release - Volume of release (modified by material type) - Some combination of the above modified by general location 1.Matrix granularity 2.Define rows & columns 3.High risk cells Data: Volume Material released Red locations Task 3 recommendation: Define severity by volume range Multiply volume by a factor (x10) for persistent materials - Only two materials modeled in Phase A - Accounts for increased adverse effect on environment Severity = volume (x10 for persistent materials) provides transparent analysis based on available data 14

15 2. Defining Severity (columns) what data will we base severity on? Task 5 Options - Effect/scale of consequence - Commitment required after the release - Detailed criteria for each impacted aspect - worst aspect represents the scenario - Single measure of environmental impact [E-Score] - (weighted) sum of impact scores 1.Matrix granularity 2.Define rows & columns 3.High risk cells Data - quantified impacts on: Aquatic receptors Marine mammals Marine flora Terrestrial receptors More Task 5 recommendation: Define severity by volume range Develop a numerical measure of E impact - Score each aspect and sum all scores - Allows transparent comparison of scenarios - Severity is greater when more than one E aspect is impacted Severity = E-score provides transparent weighting of factors and consideration of all effects (not worst one only) 15

16 Scenario Development from Which Cells? 1.Matrix granularity 2.Define rows & columns 3.High risk cells Red cells only - Upper right 3 cells should be enough - Buffer of an order of magnitude (3 more cells) - (Recommended) Frequency of Occurrence/ Likelihood Frequent (A) Occasional (B) Seldom (C) Remote (D) Unlikely (E) Incidental (5) Low Risk Severity of Incident (or Consequence) Minor (4) Serious (3) Major (2) High Risk Catastrophic (1) Red cells and orange cells - Every cell represents about an order or magnitude difference in risk from an adjacent cell - All spills in orange cells are at least a factor of 10 lower risk significance than spills in the red cells on the basis of mass/ volume spilled (i.e. not taking into account the ecotoxicity of the spill material done in Task 5). - Worthy option if gal in a certain Aleutians location could have the same environmental severity as 10,000 gal in a different Aleutians location (same material spilled) - If true, now we must define the locations of highest concern to avoid poor study results Scenarios from red cells identify all the high risk scenarios of potential concern 16

17 Recommended Approach Task 3 Goal: Identify the hazardous substances, representative spill sizes, and locations of spills associated with the highest-risk accidents. Key issue: 1. Matrix granularity Recommendation: 1. 5x5 2. Define rows & columns Severity criteria (2x in Phase A) 3. Define high risk cells 2. Scale matrix to fit data Task 3 Severity = volume (x10 for persistent) Task 5 Severity = E-score 3. Red cells (6) Next steps Develop aspects and weighting factors for E-score Completion needed when Task 5 begins 17

18 Risk Matrices - Agreed Path Forward 18