Unexploded Ordnance (UXO) Risk Management Hazard and Risk Assessments in Offshore European Waters. Lee Gooderham Principal Consultant

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1 Unexploded Ordnance (UXO) Risk Management Hazard and Risk Assessments in Offshore European Waters Lee Gooderham Principal Consultant

2 Agenda Introduction Risk tolerability and applying ALARP. Current best practice and risk management framework. Facets to an offshore UXO risk assessment, when implement early and throughout the project life-cycle. Clear outputs from the study to unsure it is a useable operation document for the client.

3 Why consider UXO? - Legislation the main four in the UK Health and Safety Drivers Health & Safety at Work (H&SW) Act 1974 Management of H&SW Regulations 1999 Construction Design and Management Regulations 2007 Corporate Manslaughter and Corporate Homicide Act 2007 The effects of high explosives

4 Defining Hazard and Risk Although hazard and risk are often used interchangeably in everyday vocabulary, it is useful to make a conceptual distinction between a "hazard" and a "risk" as follows: Hazard - the potential for harm arising from an intrinsic property or disposition of something to cause detriment Risk - the chance that someone or something that is valued will be adversely affected in a stipulated way by the hazard Irrespective of the precise definitions, "risk" has two key components: Likelihood or frequency component (representing the extent of the chance or possibility) Consequence or severity component (representing the extent of the adverse impact or danger)

5 Risk Calculation Risk = Probability x Consequence

6 Ordtek s Risk Management Framework Ordtek's UXO Risk Management Framework for the amelioration of UXO risks consists of six interrelated and sequential components, (which are specifically designed to discharge clients legal liabilities to ALARP).

7 As Low As Reasonably Practicable (ALARP)

8 ALARP and Risk Tolerability When applying ALARP for UXO one should consider: ALARP is a conceptual model and its application is not mandated through legislation. Furthermore, there are no legislated quantified boundaries to determine what are tolerable residual risks. Expert judgement based on experience, best practice and benchmarked against similar projects. The nature and level of the risks are comprehensively assessed and the results used transparently determine control measures. The residual risks are not unduly high and considered de minimis. The risks are periodically reviewed to ensure that they still meet the ALARP criteria.

9 Ordtek s Risk Management Framework

10 Stage One Historical Desk Based Hazard Assessment Comprehensive research required, not one source has all of the required data example of project in France. Public archives. Military sources. Historical data to be digitised and georeferenced for spatial mapping.

11 Stage One Historical Desk Based Hazard Assessment Important to subdivide the site based on the UXO threat sources to determine the probability of encounter.

12 Ordtek s Risk Management Framework

13 Stage Two Conceptual Risk Assessment Important to subdivide the site based on the environmental factors to determine UXO burial, UXO migration and the geophysical methods required to detect the UXO threat items.

14 Conceptual Risk Model and Environmental Interaction Detonation Effects Burial from Initial Impact of Bomb or air-delivered mine UXO Burial through natural processes UXO Migration How would a LMB mine, for example, interact with the project site?.

15 Stage Two Conceptual Risk Assessment This risk assessment model is generally considered best practice for assessing risk in the marine environment, although it has been modified where required to ensure it is UXO centric.

16 Ordtek Risk Assessment

17 Geophysical Survey and Mitigation Ahead of Geotechnical Investigation Risk assessment and ALARP test will demonstrate that generally: Probability of UXO encounter is low. Therefore the risk to the geotechnical campaign is low. Level of mitigation required is proportionate to the risk, therefore a lower specification of geophysical campaign is warranted. Client will require survey specification and Data Quality Objectives

18 Ordtek s Risk Management Framework

19 Stage Three Site Investigation Data Review the existing risk assessment and conceptual site model with: Geotechnical data (CPTs etc). Geophysical data. This is undertaken in the knowledge that a Phase One geophysical survey will not be as comprehensive in terms of: Coverage compared with an engineering survey. Sensors deployed - Magnetometer line spacing will be wide circa 50m.

20 Conceptual Risk Model and Environmental Interaction - Refinement Detonation Effects Burial from Initial Impact of Bomb or air-delivered Mine UXO Burial through natural processes UXO Migration How would a LMB mine, for example, interact with the project site?

21 Ordtek Semi Quantitative Risk Assessment (SQRA)

22 Geophysical Survey and Risk Mitigation ahead of engineering areas (WTG boxes and cable corridors) Risk assessment and ALARP test will demonstrate that generally: Client will require survey specification and Data Quality Objectives Probability of UXO encounter is greater due to scale of operations. Given the cost of vessels and program risk, other factors must be considered Level of mitigation required is proportionate to the holistic project risk, therefore a higher specification of geophysical campaign is warranted as relocation or WTG etc not an option.

23 Ordtek s Risk Management Framework

24 UXO Risk Mitigation Recommendations The key output for the client is: Comprehensive data analysis. Robust and transparent risk assessment. Clear and concise recommendations. A mitigation strategy to lower the risk to ALARP and work alongside the project programme and maintenance the integrity of the project. These may include: Geophysical contact avoidance by a realistic safety distance. Geophysical contact investigation. Safety briefings.