b'REPORT ON THE AUDIT OF THE CONSOLIDATED FINANCIAL STATEMENTS (Continued)KEY AUDIT MATTERS (Continued)Key audit matter How our audit addressed the key audit matterESTIMATION OF DECOMMISSIONING Our audit procedures focused on the work of the AND RESTORATION PROVISIONS consolidated entitys specialists.Provisions associated with decommissioning andIn obtaining sufficient audit evidence, we:restoration are disclosed in Section 4.8 to the consolidated financial statements; a descriptionassessed the competence and objectivity of bothof the accounting policy and key judgements andthe Groups internal and external specialists estimates is included in Section 2.4. involved in the estimation process;The calculation of decommissioning andassessed the reasonableness of therestoration provisions is conducted by specialistassumptions utilized by the specialists in the engineers and requires the use of significantdetermination of the provisions;judgement in the application of key assumptionsunderstood the Groups decommissioning and in respect of asset lives, timing of restoration work being undertaken, environmental legislativerestoration estimation processes;requirements, the extent of restoration activitiestested the consistency in the application of required and estimation of future costs.Changes in these assumptions may result in materialprinciples and assumptions to other areas changes to the decommissioning and restorationof the audit such as reserves estimation and provisions recorded by the Group. impairment testing;tested the mathematical accuracy of the netpresent value calculations and discount rate applied; and;reconciled the calculations to the financial reportprepared by internal and external specialists.29'