Supplementary information files for <i>In-situ</i> comparison of high-order detonations and low-order deflagration methodologies for underwater unexploded ordnance (UXO) disposal

© the authors, CC-BY NC ND 4.0Supplementary files for article <i>In-situ</i> comparison of high-order detonations and low-order deflagration methodologies for underwater unexploded ordnance (UXO) disposalThe unexploded ordnance (UXO) on the seabed off Northwest Europe poses a hazard to offshore developments such as windfarms. The traditional removal method is through high-order detonation of a donor explosive charge placed adjacent to the UXO, which poses a risk of injury or death to marine mammals and other fauna from the high sound levels produced and is destructive to the seabed. This paper describes a sea-trial in the Danish Great Belt to compare the sound produced by high-order detonations with that produced by deflagration, a low-order disposal method that offers reduced environmental impact from noise. The results demonstrate a substantial reduction over high-order detonation, with the peak sound pressure level and sound exposure level being around 20 dB lower for the deflagration. The damage to the seabed was also considerably reduced for deflagration, although there was some evidence for residues of explosives related chemicals in sediments.© 作者保留所有权利，采用CC-BY-NC-ND 4.0许可协议。本文件为论文《原位（in-situ）对比水下未爆炸弹药（unexploded ordnance, UXO）处置所用的高阶爆轰与低阶爆燃方法》的补充材料。西北欧近海海床中的未爆炸弹药对海上风电场等近海开发项目构成安全隐患。传统处置方式为在未爆炸弹药旁布设主起爆装药并实施高阶爆轰（high-order detonation），但该方法会因产生高强度声波，对海洋哺乳动物及其他海洋生物造成致死或致伤风险，同时会破坏海床生态环境。本文介绍了在丹麦大贝尔特海峡开展的海上试验，该试验旨在对比高阶爆轰与低阶爆燃（low-order deflagration，一种可降低噪声环境影响的新型处置手段）所产生的声学信号。试验结果表明，相较于高阶爆轰，爆燃方式的声学排放大幅降低，其峰值声压级（peak sound pressure level）与声暴露级（sound exposure level）均低约20 dB。此外，爆燃方式对海床的破坏程度也显著降低，不过在沉积物中仍检测到了与炸药相关的化学残留物。