2 David Low Way - Attachment 6 - UXO Assessment - OPEC

                                                                                OPEC - 2 David Low Highway, Castaways Beach
                                                                                                   Rev 02 – AFU – 10 Aug 2017


REDUCTION OF RISKS - MITIGATIONS/CONTROLS
Due to the relatively high likelihood of dangerous EO/UXO existing on the Site, the full suite of
mitigations is recommended including the following:
         Conduct EO/UXO awareness/education for personnel/contractors working at the Site,
          selected Client management staff and possibly other key stakeholders as well as implement
          a ‘chance UXO find’ protocol/SWP (preventative control and mitigating control). This is an
          important control even if areas have been UXO-remediated for the following reasons:
             o     UXO search/remediation processes are rarely 100% effective – a performance target
                   of 99.7% is generally accepted within the EO/UXO industry. It is important that those
                   using remediated sites understand that ‘chance finds’ of occasional EO/UXO could still
                   occur and be observant during their work.
             o     EO/UXO awareness/education is also a key control used reduce ‘perceptions of risk’ by
                   dispelling common myths and misunderstandings regarding EO/UXO.
             o     A proper EO/UXO Safe Working Procedure (‘Chance Find Procedure’) aims to minimise
                   unsafe practices in the event that EO/UXO are encountered and reduce the likelihood
                   that encounters will escalate to more serious consequences.
         Conduct visual detector-supported inspection of the entire development footprint to
          identify any surface of very shallow-buried EO items.
         Undertake 100% UXO investigation/remediation work of all areas where ground-intrusive
          work is planned (areas previously subjected to ground intrusive work may be able to be
          excluded depending on the nature of any such previous works).
         Review insurances and proposed contract clauses to ensure that these adequately address
          EO/UXO risks. As discussed previously, legal and contractual issues surrounding remnant
          EO/UXO are unclear and largely untested.
         Review risk assessment as new data from research and field work comes to hand. Ongoing
          re-evaluation of risks is a key aspect of an effective risk management system.

MITIGATED RISK RATINGS
Assuming the recommended mitigations/controls are adopted, the mitigated risk ratings remaining
after risk treatment (residual risk) are as shown in Table 4 (below). In nearly all cases, residual risks
are significantly reduced and normally within ‘tolerable’ levels (i.e. ‘As Low As Reasonably
Practicable’/ALARP):
                             Table 4 - Mitigated Risk Ratings (Mitigations/Controls Applied)
                                                                                              Risk Ratings & Scores
         Risk Event                Consequence Type              Controls           Probability     Consequence      Risk Score &
                                                                                       Term            Term              Term
                                                              UXO survey
                                                                                                                          11
                                  H&S                         Awareness               Rare        Catastrophic
                                                                                                                         High
                                                              SWP
                                  Note: When using conventional 5x5 Risk Assessment Matrices, it is almost impossible to
Explosion                         reduce the overall risk rating for UXO-related H&S events into the ‘green’ zone – even if
                                  the probability is rare or almost impossible. This does not mean that the residual risks are
                                  not tolerable but rather illustrates the difficulties that can arise when using relatively
                                  simplistic risk decision tools. Other more sophisticated risk modelling tools may
                                  demonstrate that risks are extremely low (negligible) however there will usually be some
                                  residual risk of a fatality/serious injuries even if full remediation of the Site is undertaken.



For use only in relation to the specified project
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