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UXO Risk Assessment Methods: Critical Review. Jacqueline MacDonald, Debra Knopman, J. R. Lockwood, Gary Cecchine, Henry Willis RAND. Briefing Outline. Need for UXO risk assessment methods Prioritization Site-specific assessment RAND review of existing methods: tasks, approach
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UXO Risk Assessment Methods: Critical Review Jacqueline MacDonald, Debra Knopman, J. R. Lockwood, Gary Cecchine, Henry Willis RAND
Briefing Outline • Need for UXO risk assessment methods • Prioritization • Site-specific assessment • RAND review of existing methods: tasks, approach • Design features and limitations of existing methods • RAND recommendations for improving UXO risk assessment • Prioritization • Site-specific assessment
Need for UXO Risk Assessment • Prioritization: mandated by Congress • Site-specific assessment • Alternative response options have enormous cost implications • Total current cost estimate of $14 billion assumes mag-and-flag approach • Alternative approaches proposed by regulatory agencies could cost much more • DOD needs to understand risk reduction differences among alternative approaches
Alternatives for UXO Response • Surface clearance only • Scan with metal detector, and excavate each anomaly to a specific depth (e.g. 2 ft, 3 ft) • Scan, excavate each anomaly, scan bottom of hole, and excavate again if anomaly is detected • Scan and excavate anomalies, and then repeat the process two or more times • Excavate the entire site in one-foot lifts to depths of 2 ft, 4 ft, or more; sift the excavated soil to remove UXO
Scan land with best available technology (at surface, one scan effort) Excavate all anomalies found to maximum depth (4 feet) Provide construction support to property developers Scan land (surface & 1ft) Excavate anomalies found Excavate entire site to 2 ft Scan land (2ft level) Excavate anomalies found Excavate entire site to 3 ft Scan land (3ft level) Excavate anomalies found Excavate entire site to 4 ft Scan land (4ft level) Excavate anomalies found Alternatives Proposed at Ft. X Army’s Preferred Approach State EPA’s Preferred Approach
Cost Differences Among Ft. X Options Are Hundreds of Millions of Dollars
Briefing Outline • Need for UXO risk assessment methods • Prioritization • Site-specific assessment • RAND review of existing methods • Design features and limitations of existing methods • RAND recommendations for improving UXO risk assessment • Prioritization • Site-specific assessment
RAND Tasks • Client: Army Chief of Staff for Installation Management • Tasks: • Conduct a preliminary analysis of ongoing efforts in UXO risk assessment, including: • Ordnance and Explosives Cost-Effectiveness Risk Tool • Interim Range Rule Risk Methodology • Ordnance and Explosives Risk Impact Analysis • Risk Assessment Code
Tasks, continued • Study methods used by the Department of Energy, National Aeronatuics and Space Administration, and others to evaluate and measure risk of low-probability and high-consequence events. • Recommend how the Army could develop a risk assessment/risk management protocol for UXO sites.
Study Approach • Develop criteria for a technically sound risk assessment, based on risk assessment literature survey and consultations with experts • Read all documentation for available methods; test software if available • Interview method developers • Evaluate extent to which each method satisfies the evaluation criteria
Briefing Outline • Need for UXO risk assessment methods • Prioritization • Site-specific assessment • RAND review of existing methods • Design features and limitations of existing methods • RAND recommendations for improving UXO risk assessment • Prioritization • Site-specific assessment
Operation of the Explosives Safety Risk Tool • (Add all slides from UXO/Countermine Forum briefing)
Briefing Outline • Need for UXO risk assessment methods • Prioritization • Site-specific assessment • RAND review of existing methods • Design features and limitations of existing methods • RAND recommendations for improving UXO risk assessment • Prioritization • Site-specific assessment
[Insert slides on prioritization system from final briefing]
Briefing Outline • Need for UXO risk assessment methods • Prioritization • Site-specific assessment • RAND review of existing methods • Design features and limitations of existing methods • RAND recommendations for improving UXO risk assessment • Prioritization • Site-specific assessment
We Searched Other Agencies for Risk Assessment Models • [Use slide from countermine forum briefing, but modify “scenarios approach” to read “PRA”; also, place EPA first in list, and split FAA and NRC, and eliminate OSHA] • Then, insert slides 28, 29, 30 from countermine forum briefing
Summary of Recommended Approach for Site-Specific Risk Assessment • Use EPA Risk Assessment Guidace for Superfund methods to assess risks of munitions constituents • Develop probabilistic risk assessment method specific to UXO to assess explosion risks • Development should be overseen by a technical advisory committee • The method should be independently peer reviewed • Template “trees” should be developed • Trees then could be modified at individual sites, with substantial stakeholder input
Summary • Existing methods for UXO risk assessment do not satisfy criteria for technical credibility • New prioritization method should include a two-tier screen: • Tier 1: sort by explosion risks (using RRSE or HRS) • Tier 2: sort by constituent risks (using new method—possibly a modified RAC) • New site-specific assessment method should • Use RAGS for constituent risks • Use new PRA method for explosion risks