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Summary Risk assessment is a systematic approach used to evaluate the level of safety of a complex system or operation and to recommend appro- priate safety improvement measures. It is an established engineering discipline with application in many industrial enterprises for which safety is a paramount concern, such as nuclear reactors, large chemi- cal plants, and the airline industry. Risk assessment is also widely used in the marine industry by government and private authorities to help manage safe shipping operations. Assessing risk involves addressing three key questions: What can go wrong? How likely is it? and What are the impacts? These questions are organized systematically into discrete steps that involve identifying hazards (or creating risk sce- narios), determining the likelihood of their occurrence, and iden- tifying their consequences. The present study applies such classic fundamentals of risk assessment to the question of how to mini- mize vessel accidents and spills in the Aleutian Islands and recom- mends an appropriate framework for conducting a comprehensive risk assessment for such events. The Aleutian Islands are a 1,200-mile chain of small volcanic islands in the North Paciï¬c stretching westward from the Alaska Peninsula to Russia. In addition to their biological, cultural, and eco- logical signiï¬cance, these islands have long been politically and 1
2 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands economically important. The Aleutians are located along the short- est transportation route for commercial vessels traveling between northwestern North America and Asia. More than 4,500 large com- mercial vessels annually now traverse Unimak Pass at the eastern end of the Aleutiansâa number that has steadily risen in recent years and is anticipated to continue to grow with increases in vessel trafï¬c between Asia and North America, including the Arctic as well as the Aleutians Islands. In December 2004, the grounding and breakup of the bulk carrier M/V Selendang Ayu during a severe storm focused public attention on the oil spill risks posed by vessels transiting the Aleutians. The accident caused the death of six crew members when a U.S. Coast Guard (USCG) rescue helicopter crashed. It also resulted in a spill of 336,000 gallons of heavy fuel oil near the shore of Unimak Island. While this incident was particularly severe, other accidents, spills, and near misses have taken place and continue to occur in the region. The court settlement following the M/V Selendang Ayu accident speciï¬ed that funds be allocated for a comprehensive risk assess- ment of ship accidents and spills in the Aleutians and for conduct of projects identiï¬ed by the risk assessment. This study, conducted by a committee empaneled by the Trans- portation Research Board of the National Academies, was initi- ated to provide guidance for the conduct of that assessment. The charge to the committee was to examine available data and evi- dence about the risk of spills from vessels transiting the Aleutian Islands, determine the information needed to conduct a compre- hensive risk assessment, recommend a framework for the most appropriate and scientiï¬cally rigorous risk assessment approach possible given available data and modeling capability, and identify how the risk assessment could be conducted in a logical sequence of discrete steps. The risk posed to people and the environment by shipping in the Aleutians is greatly inï¬uenced by the regionâs unique set- ting, harsh environment, and difï¬cult operating conditions. Such factors as geography, climate, regulatory regime, population and its cultural base, ecology, and industrial activities all combine to deï¬ne this special operating environment. Assessing the risk in this environment requires a full understanding of these con- ditions and factors as they are at present and as they may change over time.
Summary â¢ 3 This report reviews and evaluates available information on the cur- rent system and operating environment for shipping in the Aleutian Islands. It presents the committeeâs proposed design for a com- prehensive risk assessment for the evaluation of vessel accidents and spills in the Aleutians and recommendations for an appro- priate framework for the conduct of that assessment. These rec- ommendations identify a logical sequence of building blocks that can be used to conduct the assessment in discrete steps so that early decisions can be made regarding the most important safety improvements and risk mitigation options can be considered in the order of their priority. STUDY CONTEXT The Aleutian Islands: Resources and Infrastructure Central to the public concern about improving the safety of shipping in the Aleutian Islands are the unique and valuable natural resources in the region that could suffer damage from vessel accidents. Indeed, history has shown that oil spill accidents in the Aleutians are not uncommon, in large part because of the frequent and sudden storms, high winds, and severe sea conditions to which the region is subject. Response to these events is often ineffective as a result of the severe weather conditions and a lack of adequate salvage and spill response infrastructure (for example, there are no large rescue-capable tugs). The Aleutian region is home to natural resources found nowhere else in the world. Because of the vast diversity of species over a broad area, most of the Aleutian Island chain has been designated as a national wildlife refuge. Few marine areas in the world match the Aleutians in marine productivity, and Dutch Harbor is the leading U.S. ï¬shing port in tonnage landed. Large commercial vessels engaged in the substantial and growing maritime trade between northwestern North America and northern Asia travel the North Paciï¬c Great Circle Route that traverses the Aleutian Islands. The 4,500 vessels that transit Unimak Pass annually are a mix of large containerships, bulk carriers, car carriers, tankers, and othersâthe majority foreign ï¬agged and on âinnocent passageâ through these waters. These vessels carry large quantities
4 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands of fuel oil and various cargoes, including chemicals and other haz- ardous materials. The spill risk they pose will grow as their trafï¬c volume increases and as new shipping routes emerge to serve future resource development in Alaska and other Arctic regions. The volume of vessel trafï¬c through Unimak Pass is roughly double that calling on all ports in the 17th USCG District (Alaska). Vessels entering those major ports are subject to a set of controls, whereas similar vessels traveling on innocent passage through the Aleutians need not meet comparable requirements. Vessel Accidents and Spills In the region near Dutch Harbor, large commercial ship trafï¬c is concentrated in and near Unimak Pass, and the local ï¬shing ï¬eet, tugs and barges, ferries, and other small vessels often cross the large- ship trafï¬c lanes. Farther out in the Aleutian chain, the trafï¬c is more dispersed, but hazards are always present. Since 2005, because of new automatic identiï¬cation system (AIS) carriage requirements and the installation of AIS stations in the area, the Marine Exchange of Alaska has been collecting data on ship transits through Uni- mak Pass for USCG. These data identify and characterize each ves- sel transit, and the annual reports produced from the data can be combined with incident/accident reports to determine historical patterns. Historical data on accidents and spills near the Aleutian Islands show that ï¬shing vessels account for the majority of the accidents, most of these resulting in small spills, while the large commercial ï¬eet has experienced only a few major accidents but with much larger spill volumes. Over the past 20 years, about 20 ï¬shing vessel accidents with spills in excess of 1,000 gallons were recorded, while just two commercial cargo vessel accidents (the M/V Selendang Ayu in 2004 and the M/V Kuroshima in 1997) spilled 336,000 and 40,000 gallons, respectively. Data for the past 20 years on response to spills in the Aleutians have also shown that almost no oil has been recovered during events in which recovery attempts have been made by the responsible par- ties or government agencies and that in many cases, weather and other conditions have prevented any response at all. This evidence and other data on the difï¬culty of recovering oil from the sea in open ocean environments and severe weather conditions lead the
Summary â¢ 5 committee to suggest that accident and spill prevention be given high priority in considering risk reduction options. Safety Infrastructure The 1,200-mile-long Aleutian Island chain is remote and sparsely populated. It has few sizable harbors and minimal maritime infrastructureâespecially with respect to the ability to respond to vessels in distress. Given this limited infrastructure and the harsh climate and other hazards to shipping that characterize the region, mariners are challenged to maintain safe operations. The committee therefore reviewed the existing infrastructure and safety measures (such as practices on board and in port, regulations, and the use of vessel monitoring and tracking systems) to identify key areas for improvement that should be considered in assessing the risk of vessel accidents and spills in the Aleutian Islands. Reliable communications are vital to safe shipping, and the com- mittee found that there are signiï¬cant gaps in coverage within the Aleutian study area. Moreover, several accident reports cite poor communications as a factor contributing to a chain of events lead- ing to serious problems. Vessel monitoring and tracking systems also can enhance safe operations. The advent of AIS technology has improved trafï¬c management capabilities and offers the potential for active monitoring and early identiï¬cation of problems. Beginning January 1, 2009, vessel tracking capability will be further improved by International Maritime Organization (IMO) regulations requiring cargo ships above 300 gross tons to transmit long-range identiï¬cation and tracking technology (LRIT) data. When vessels at sea do experience problems, it is important to have an effective response capability. Tug capability for assist- ing large vessels in distress does not exist in the Aleutians. Only small harbor tugs are stationed in Dutch Harbor, and they are not rescue-capable. While Dutch Harbor authorities have prepared Emergency Towing System packages that represent an important step toward improving shipping safety in and near the harbor, their coverage is primarily local; other areas in the Aleutians remain more vulnerable. None of the existing measures are adequate for respond- ing to large vessels under severe weather conditions, and the sub- stantial funding normally required for such a capability has not been identiï¬ed.
6 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands RECOMMENDATIONS Risk Assessment Framework The committee developed a risk assessment framework for ana- lyzing the commercial shipping system in the Aleutian region, both in its current state and projected into the future, with respect to accidents and spills resulting in harm to people and the environ- ment. The proposed framework can be used to evaluate hazards, identify current levels of risk, investigate risk reduction measures, analyze the costs and beneï¬ts of those measures, and justify safety improvements to the system. The committee recommends that a structured risk assessment be performed with two major phasesâa Phase A Preliminary Risk Assessment and a Phase B Focused Risk Assessment. This process would include a speciï¬c, stepped approach to collecting and catego- rizing available data; development of a logical sequence of events deï¬ning key scenarios; and use of a risk matrix for an initial qualitative evaluation of risk levels. The Phase A Preliminary Risk Assessment should begin with semiquantitative studies aimed at trafï¬c characterization and pro- jections, spill estimates, and identiï¬cation of the highest risks. This information should then be used for a qualitative assessment and prioritization of risk reduction options. The Phase B Focused Risk Assessment should entail detailed, in-depth assessments of individual risk reduction options in order of priority. The time and resources dedicated to Phase A should be limited to ensure that it is completed in a timely manner and that sufï¬cient resources have been reserved for Phase B. Phase B should be accomplished in discrete steps as necessary in accordance with the priority of measures to be investigated and the level of risk reduction possible. The committee believes that this framework would enable risks to be evaluated effectively and efï¬ciently within the resources available. It would also allow for explicit and com- parative evaluations of risk reduction measures using more ana- lytical techniques, such as modeling and costâbeneï¬t studies, when warranted. The committee also recommends that the risk assessment include a quantitative fate and effect consequence analysis to yield an under- standing of the damage to natural resources and socioeconomic
Summary â¢ 7 impacts associated with different hazards, sizes of spills, and acci- dent locations. The committee believes that a preliminary conse- quence analysis should be conducted in Phase A and a more detailed analysis, including biological impacts, in Phase B. Organization of the Risk Assessment Study An effective study organization is vital to the success of a risk assess- ment. The committee reviewed various risk assessment approaches and techniques, including those employed in recent marine risk assessments that are relevant to the problem at hand. This expe- rience points to the importance of certain elements: the problem should be clearly deï¬ned, and a contractor should be provided with the speciï¬c scope of the study and explicit goals; a peer review group should be given responsibility for reviewing and commenting on the study methodology and the handling of uncertainties; and a stakeholder group should be included in framing the issues, identi- fying local expert knowledge, suggesting risk reduction measures, and reviewing ï¬nal results. The committee recommends that the risk assessment be orga- nized and managed by a team consisting of USCG, its designated fund management organization (the National Fish and Wildlife Foundation), and the State of Alaska. The Management Team should provide oversight of the contractor(s) conducting the risk assessment. The committee recommends that the Management Team appoint a Risk Assessment Advisory Panel with a facilitator and members consisting of experts and key parties with an interest in furthering the goals of the risk assessment. Recognizing the importance of stake- holder involvement to the success of the risk assessment, the commit- tee suggests that the Advisory Panel represent all major Aleutian Islands stakeholders, who would provide relevant local knowl- edge and expertise to the contractors. The panel should review and comment on the framing of the study and its conduct at key stages and help identify and provide input on the risk reduction measures to be evaluated. The committee also recommends that the Management Team appoint a Risk Assessment Peer Review Panel with a facilitator and members consisting of experts in the techniques and methodolo- gies of risk assessment to ensure that the study will be conducted
8 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands with sufï¬cient attention to completeness, accuracy, rigor, and transparency. Finally, the committeeâs charge was to develop the framework for a risk assessment. The committee believes that ongoing risk man- agement is a critical part of the risk assessment process. Thus, the framework proposed in this report is structured to ensure effective implementation of the most cost-effective risk reduction measures by establishing Phase B as a detailed risk management project. Interim Actions to Enhance the Assessment During its review of existing data, the deï¬nition of the problem, and the current state of safety in the system, the committee identiï¬ed interim actions that would help ensure a successful risk assessment. The committee is aware of the urgency of taking actions to improve the safety of shipping operations in the Aleutian Islands, and early actions that would provide additional data to build a solid risk assessment foundation should also be considered. The committee recommends that USCG take appropriate action to expand the AIS tracking network along the Aleutian chain and covering the southern North Paciï¬c Great Circle Route. The process for taking this action is already in place, and USCG has the authority to proceed as funding is made available. It would be valuable to implement these systems and to make available the data they yield as soon as possible so the complete trafï¬c system can be described and analyzed with conï¬dence as part of the risk assessment. Collec- tion of additional AIS data should not delay this risk assessment. If it is not possible to install additional receivers and collect sufï¬cient data to contribute to the study, the augmentation of the AIS system should be given careful consideration when the Phase A study results become available. When LRIT data become available, USCG should take steps to utilize these data to further improve vessel tracking in and around the Aleutian chain. Having an adequate rescue tug capability in the region has been identiï¬ed in the past as a risk reduction option with obvious beneï¬ts for responding to large commercial vessels in distress. This capabil- ity has been established in other locations where the potential for maritime accidents exists, and local stakeholders in the Aleutians have advocated this solution for many years. While the committee has not evaluated the costs and beneï¬ts of this option, it has con-
Summary â¢ 9 cluded that such an evaluation could not begin without more infor- mation about costs and possible ï¬nancing mechanisms. Therefore, should the Phase A assessment conclude that rescue tugs have potential risk reduction beneï¬ts, the committee recommends that USCG and the State of Alaska be ready and available to investigate funding levels, sources, and mechanisms for an Aleutian Rescue Tug, with the expectation that the Risk Assessment Management Team and Advisory Panel might request this information for early consideration within the risk assessment process. The committee further recommends that USCG be ready and available to investigate the possible structure and costs of a Vessel Trafï¬c Information System within and near Unimak Pass and Dutch Harbor, with the expectation that the Risk Assessment Manage- ment Team and Advisory Panel might request the information thus generated early in the risk assessment process. This action would facilitate the risk assessment and provide needed data for costâbeneï¬t analyses of selected options. Subject to the ï¬ndings of the Phase A Preliminary Risk Assess- ment, the committee also recommends early consideration of options for tracking and monitoring vessel trafï¬c in certain congested areas, as well as for employing some common trafï¬c management schemes that have shown merit in similar locations worldwide. Implementing voluntary vessel trafï¬c systems, establishing trafï¬c lanes, and iden- tifying particularly sensitive sea areas or areas to be avoided are among the measures that USCG could pursue without new author- ity. Some of these measures might require IMO consideration, while others might be adopted unilaterally. CONDUCT OF THE RISK ASSESSMENT STUDY Building on the recommendations presented above, the committee has outlined the process and speciï¬c steps it believes should be fol- lowed to conduct a successful risk assessment for shipping operations in the Aleutian Islands. Problem Deï¬nition, Scope, and Budget The primary goal of the risk assessment is to determine whether risk reduction measures are necessary and then to recommend the
10 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands TABLE S-1 Hazardous Substances Marpol Annex Type or Other Code Name Example Oil Annex I Oil cargo Crude oil, asphalt- blending stocks, fuel oil no. 4, fuel oil no. 5, fuel oil no. 6, diesel oil Annex I Biofuels and base petroleum fuels Annex I Bunkers Diesel oil, lube oil, heavy fuel oil Chemicals Annex II and IBC Noxious liquids in Vegetable oils, oil-like Code (Chapters bulk and noxious substances 17 and 18) liquid substances Annex II and Biofuels Biodiesel, fatty acid methyl IBC Code esters, B100 and ethanol, ethyl alcohol E100 Other Annex III Dangerous goods in Microorganisms, rats hazardous package form and substances invasive species Note: IBC = international bulk container. implementation of effective and efï¬cient risk reduction measures. To achieve this goal within available resources, the study must focus on the speciï¬c problem at handârisks related to accidental spills from vessels operating in the study region. To provide the needed focus, the committee has deï¬ned the types of hazardous substances, types of accidents, geographic region, and time frame to be considered for the study. Table S-1 identiï¬es the hazardous substances that need to be addressed, while Figure S-1 illustrates the study region, which includes the entire Aleutian Island chain and encompasses the region traversed by commercial vessels on the North Paciï¬c Great Circle Route. Because the system and the problem are so complex, the commit- tee recommends that the study be conducted in phasesâbeginning with qualitative and semiquantitative analyses and assessments, fol- lowed by selected detailed quantitative assessments of signiï¬cant risks and most promising risk reduction measures. The prioritization of potential risk reduction measures should be an ongoing, iterative process throughout all of these efforts, reï¬ecting analysis results as they become available, changing circumstances, and emerging tech- nologies and opportunities.
Summary â¢ 11 170Â°E 175Â°E 180Â° 175Â°W 170Â°W 165Â°W 160Â°W 55Â°N 50Â°N FIGURE S-1 Complete Aleutian chain. The Advisory Panel should be structured to build trust, clarify the values and goals for the assessment, provide local knowledge, and identify needed organizational learning and policy changes. It should also help establish tolerance parameters for risk and, together with the Management Team, perform an initial prioritiza- tion of risk reduction measures. The committee has concluded that, regardless of how rigorous it may be, an analytical approach to risk assessment alone is insufï¬cient for decision making. The needs and values of stakeholders play a key role and must be considered in the decision-making process. The basic steps and time line for the risk assessment are shown in Figures S-2 and S-3. The ï¬gures show the relationships among the four groups involved in management, oversight, and conduct of the risk assessment and the primary responsibilities of each. The committee believes that approximately 2 years will be required for the full assessment. The process is structured so that a qualitative prioritization of risk reduction measures will be available after the ï¬rst year, which may allow for earlier implementation of those measures that stand out as particularly effective. In accordance with the court settlement resulting from a com- mercial vessel accident and large oil spill in 2004, $3 million has been set aside for the overall risk assessment and projects iden- tiï¬ed by the assessment. The committee is conï¬dent that the available funds are more than sufï¬cient to cover the costs of a credible comprehensive risk assessment; however, the Manage- ment Team must control the scope of the effort to ensure that the work is done in a timely fashion and that early efforts are not devoted to detailed analyses that will not inï¬uence the ï¬nal decisions.
12 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands Management Advisory Risk Analysis Peer Review Team Panel Team Panel Semiquantitative Studies Develop Draft RFP Review Draft RFP for for Phase A Preliminary Phase A Preliminary Risk Assessment Risk Assessment and Provide Input/Comments Update Phase A RFP Considering Advisory Panel Input/Comments Solicit Responses to RFP Review and Comment and Award Contract on Responses for Phase A Study to RFP Phase A Contractor(s) Selected Meeting of Management Team, Advisory Panel, and Contractor (review overall work process and responsibilities; Advisory Panel and Management Team provide input to Contractor) Select Members of Peer Review Panel Peer Review Panel Established Draft Report on Phase A Discuss and Draft Risk Matrix 8 Months Traffic and Spill Evaluation Approach Likelihood/Size Review Phase A Review Phase A Review Phase A Traffic and Spill Traffic and Spill Traffic and Spill Likelihood/Size Analysis Likelihood/Size Analysis Likelihood/Size Analysis Provide Comments on Update Draft Report on Draft Phase A Traffic/Spill Phase A Traffic and Spill Report to Contractor Likelihood/Size Meeting of Management Team, Advisory Panel, and Contractor (discuss baseline spill risk report; review risk matrix evaluation approach; discuss scope of Phase A consequence analysis) Specify Scope of Phase A Draft Report on Phase A Consequence Analysis Consequence Analysis Review Phase A Review Phase A Review Phase A Consequence Analysis Consequence Analysis Consequence Analysis Provide Comments on Final Report on Phase A Draft Phase A Consequence Traffic/Spill/Consequence Report to Contractor Studies Qualitative Assessment and Prioritization of Risk Reduction Options Meeting of Management Team, Advisory Panel, and Contractor (establish list of potential risk reduction measures; prioritize list of risk reduction measures) Develop rankings for 3 Months accident scenarios Identify and qualitatively evaluate potential risk reduction options Prioritize risk reduction options FIGURE S-2 Phase A Preliminary Risk Assessment. (RFP = request for proposals.)
Summary â¢ 13 Management Advisory Risk Analysis Peer Review Team Panel Team Panel Focused Risk Assessment Select Measures for Phase B Evaluation Develop Draft RFP Review Draft RFP for for Phase B Phase B Evaluation and Focused Risk Assessment Provide Input/Comments Update Phase B RFP Considering Advisory Panel Input/Comments 10 Months Solicit Responses to RFP Review and Comment and Award Contract for on Responses Phase B Study to RFP Phase B Contractor Selected Draft Phase B Report Review Phase B Study Review Phase B Study Review Phase B Study Provide Comments on Draft Final Report on Phase B Study Phase B Focused to Contractor Risk Assessment Development and Reporting of Findings and Recommendations Meeting of Management Team, Advisory Panel, and Contractor (discuss results of Phase B study; 3 Months prioritize list of risk reduction measures) Management Report on Recommend Measures Findings/Recommendations for Implementation and Process for Implementation FIGURE S-3 Phase B Focused Risk Assessment. The Phase A characterization of risk is needed for the initial qualitative assessment of risk reduction measures and should serve as a baseline for the focused quantitative risk reduction investiga- tions. Care must be taken to avoid spending too much of the bud- get on the Phase A effort; the committee believes that this effort can be completed for about 25 percent of the overall budget. In the Phase B analysis, there may be a natural tendency to assess more options in greater detail than resources allow, so the scope and sched- ule should be deï¬ned and adhered to as closely as practicable. If additional studies are deemed desirable, they should be consid- ered after the study has been completed as part of the ongoing effort of risk management.
14 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands Technical Approach The committeeâs proposed technical approach for conducting the risk assessment begins with the Phase A Preliminary Risk Assess- ment. The semiquantitative portions of the Phase A analysis (i.e., trafï¬c characterization and projections and spill estimates) should rely on historical data supplemented by results of prior risk stud- ies and expert opinion. This analysis should help identify geo- graphic locations and spill scenarios for a limited number of focused environmental impact investigations. The Phase A study should identify the highest risks in terms of the types of spills and vessels involved, the types of accidents and their likely causes and sce- narios, and the spill sizes and likely locations, and it should provide some sense of the environmental impacts. The intent is to provide sufï¬cient information with which to prioritize risk reduction mea- sures on a qualitative basis. The committee recommends the following speciï¬c steps to accomplish the semiquantitative portions of Phase A: â¢ Trafï¬c study: Characterize the existing ï¬eet and trafï¬c and the quantities of hazardous cargoes moved. Project growth in trade, changes in vessels, and impacts of expected regulatory changes. Project the ï¬eet makeup over a 25-year study period. â¢ Spill baseline study: Develop an oil spill baseline over the study period on the basis of projected movements of oil and hazardous materials and estimated spill rates and frequencies. The projection should provide an understanding of the most important hazards and serve as a baseline for later assessment of beneï¬ts. â¢ Identiï¬cation of high-risk accidents: Identify the hazardous sub- stances, representative spill sizes, and locations of spills associated with the highest-risk accidents. â¢ Phase A consequence analysis: For representative high-risk acci- dents, perform a high-level spill trajectory and fate analysis to gain an understanding of the relative impacts of spill size, type, and location. â¢ Accident scenario and causality study: Determine representative accident scenarios to develop probabilities for their principal causes and associated consequences. The Phase A Preliminary Risk Assessment should end with a qual- itative assessment of risk reduction options that should lead to the identiï¬cation of certain measures that merit immediate implementa-
Summary â¢ 15 tion, some that are unjustiï¬able, and others that warrant more detailed analysis.. The Advisory Panel and Management Team should populate risk matrices, compile lists of potential risk reduction measures, qualitatively assess the beneï¬ts and costs of each measure, and priori- tize the measures. The Risk Analysis Team should be available during these deliberations to provide background information and insight into the Phase A investigations. Figure S-4 illustrates a risk matrix that the committee recommends using as a structured process for reaching conclusions and establishing priorities for risk reduction measures. In the Phase B Focused Risk Assessment, the assessment approaches and techniques should be applied in more detailed, quantitative analyses to determine whether particular measures are justiï¬ed and to understand their secondary effects. A variety of techniques, such as numerical simulations, as well as expert elicitation, should be used to quantify the likelihood and consequences of an accident with and without a risk reduction measure in place. Uncertainty and sensitivity analyses should help bound the conï¬dence level of the characterization of risks and beneï¬ts. Such quantitative assess- ments should also supply data needed for costâbeneï¬t analyses. The Phase B risk analysis should follow the basic steps of Phase A. The speciï¬c modeling and analysis methods may differ because the analysis needs to be more focused, with sufï¬cient detail, precision, and data quality to allow more robust decisions on the selection, design, and implementation of cost-effective risk control measures. As noted, to the extent possible, Phase B should be a quantitative assessment. Other characteristics of the Phase B risk analysis should include the use of hybrid modeling methods for risk scenarios; more detailed causal modeling; consideration of human factors and adoption of human-error analysis techniques; evaluation of rare, high-consequence events; advanced modeling; formal use of expert opinion; and rigorous uncertainty and sensitivity analyses. The ï¬nal step in the committeeâs proposed approach is decision making and implementation of risk reduction measures. Imple- mentation of risk reduction measures will involve many challenges, including establishing sources for funding and reaching agreement with the various agencies and stakeholders that will inï¬uence the failure or success of a measure. Risk management is not a one-time solution; it requires continuous monitoring and reassessment. Thus, the committee stresses the need for a mechanism to ensure that the risk management plan remains a living document.
16 â¢ Risk of Vessel Accidents and Spills in the Aleutian Islands Frequency of Severity of Incident (or Consequences) Occurrence/ Likelihood Incidental Minor Serious Major Catastrophic (1) (2) (3) (4) (5) Frequent (5) High Risk Occasional (4) Seldom (3) Remote (2) Low Risk Unlikely (1) FIGURE S-4 Proposed risk matrix. Implementation of Risk Reduction Measures The development of risk reduction measures for implementation will require consideration of who the decision makers are and what capaci- ties they have to effect recommended changes. For example, USCG rulemaking depends on consideration of beneï¬ts relative to costs. The State of Alaska and local municipalities also have speciï¬c decision- making roles. Securing federal funds will involve other U.S. govern- ment branches, and IMO will have a role if changes to international regulations are desired. Successful implementation of certain initia- tives may require the collaboration of various government decision makers, the support of stakeholders, and a relatively longer time. Need for Transparency If the objectives of the risk assessment study are to be met, its ï¬nal report should be fully transparent, describing the study process and all relevant assumptions: â¢ Hazards and risks should be clearly identiï¬ed. For risk reduction measures that merit detailed analysis, beneï¬ts and costs should be clearly deï¬ned. â¢ All sources of data should be documented and assumptions explained. Models and methodologies should be explained in suf-
Summary â¢ 17 ï¬cient detail to allow a third party to understand the assessmentâs basic assumptions and limitations. â¢ Judgments applied during the assessment should be explicitly stated. The process for elicitation and analysis of expert opinion should be explained. â¢ Uncertainty and associated sensitivity analyses should be clearly documented and explained. Results should be presented in a way that does not create a false sense of precision. â¢ The analyses should be of sufï¬cient depth to address the needs and expectations of those with expertise in risk assessment while being understandable to the layperson. CONCLUSION Despite the complexity of the system and the open-ended nature of the problem, the committee is conï¬dent that a rigorous and com- prehensive risk assessment of shipping in the Aleutian Islands can be conducted within the available resources and that needed safety improvements can be justiï¬ed in the process. The committee also understands that, while certain historical and time-series data are lim- ited, they can be enhanced and supplemented by relevant worldwide data and local expertise and judgment. This report presents a frame- work for conducting such a risk assessment, explaining the underlying principles and offering guidelines for applying both qualitative and quantitative techniques where appropriate. Finally, throughout this report, the committee emphasizes principles that are key to ensuring a successful outcome. These include keeping the work focused on a clear deï¬nition of boundaries and scope, designing the assessment process to incorporate continuous involvement of local stakeholders, and applying a phased approach to set priorities for early action and allocate resources efï¬ciently.