Except where the context otherwise requires, in this Part of this Act “pipeline” means a pipe or system of pipes (excluding a drain or sewer) for the conveyance of any thing, together with F1all apparatus, works and services associated with the operation of such a pipe or system .

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The Secretary of State may by order provide that a part of a pipeline specified in the order shall be treated for the purposes of this Part of this Act, except this subsection, as a pipeline.