Explosives Use in Decommissioning—Guide for Assessment of Risk (EDGAR): I Determination of Sound Pressure Levels for Open Water Blasts and Severance of Conductors and Piles from Below the Seabed

Alison M Brand

doi:10.3390/modelling2040027

Abstract

A simple underwater noise model suitable for use with explosives in the decommissioning of oil and gas subsea structures is introduced and evaluated against data from five projects in the US. The performance of the model is compared to four existing models for open water blasts, and for the severance of well conductors and piles. Simulated received underwater sound pressure levels were significantly correlated with measurements for all scenarios. The maximum total error achieved between simulations and measurements was 3.5%, suggesting that predictions are accurate to within 4% of the average measurement. A low relative bias was observed in the simulations when compared to measured values, suggesting only a small systematic underestimate (≤1% of average measurement) for most severance operations and a small overestimate (1.34%) for open water blasts.

Highlights

IntroductionIn the UK, the Department for Business, Energy and Industrial Strategy (BEIS) is responsible for permitting a varied array of offshore operations and ensuring that they are conducted in a safe, effective and environmentally sound manner
In the UK, the Department for Business, Energy and Industrial Strategy (BEIS) is responsible for permitting a varied array of offshore operations and ensuring that they are conducted in a safe, effective and environmentally sound manner. Several of these activities rely upon the underwater detonation of specialised explosive charges to perform specific functions [1]
Though several nonexplosive-severance methodologies can achieve the same goal, many operators feel that explosive-severance charges offer the most flexible, cost-effective, efficient and safest cutting options

Summary

Introduction

In the UK, the Department for Business, Energy and Industrial Strategy (BEIS) is responsible for permitting a varied array of offshore operations and ensuring that they are conducted in a safe, effective and environmentally sound manner Several of these activities rely upon the underwater detonation of specialised explosive charges to perform specific functions [1]. Though several nonexplosive-severance methodologies can achieve the same goal (such as sand cutters, diver severance, abrasive water jet cutters, etc.), many operators feel that explosive-severance charges offer the most flexible, cost-effective, efficient and safest cutting options Despite their apparent advantages, the detonation of the explosives and the acoustic energy/shockwave released has the potential to injure or kill marine protected species, primarily marine mammals

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Results

Conclusion