Dam phases
The DSC oversights the safety requirements of "prescribed dams" throughout their lives from initial investigation to eventual decommissioning. Particular DSC requirements at various phases of a dam's life are set out in Information Sheet DSC14 and as follows:
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Investigation - The DSC seeks initial information on the proposal (i.e. D1 form) to determine the need for dam prescription and feedback on DSC requirements.
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Concept Design - The DSC seeks specific details of the dam, particularly its Consequence Category (see DSC13) and provides comments.
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Environmental Assessment - The DSC is interested to ensure its requirements are addressed in the statutory environmental assessment documentation.
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Detailed Design - The DSC has a regulatory role to ensure its safety requirements are covered (see DSC11, DSC16 to DSC19) by reviewing the design before proceeding to construction.
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Construction - The DSC requires close oversight of construction by the designer to ensure it is constructed in accordance with the designer's intentions.
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Commissioning - The DSC requires a Construction Report (including certificate, D4 form and Work-as-Executed drawings), Operation and Maintenance Manual and Dam Safety Emergency Plan at this stage.
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In-Service - The DSC requires submission of Surveillance Reports for all prescribed dams on commissioning and then at five yearly intervals (see DSC15 for details). Intermediate Surveillance Reports are also required for ash and tailings dams.
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Decommissioning - Dams are to be decommissioned in such a way as to remove any threats. When decommissioned, the DSC will deprescribe the dam and then has no further requirements.
Further details are under "Safety of Dams".