as shown on the

       drawings or as established by the Engineer. Any

       thickness of concrete shown on the drawings may

       be changed by order of the Engineer, in which

       case, the changed thickness will be the basis of

       measurement for payment.

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       In measuring concrete for payment, the volume of

       all individual boreholes, recesses, openings and

       metalwork, greater than 0.04 cubic meter in

       volume, will be deducted.  No allowance will be

       made for reinforcement bars, anchor bolts, water

       stops, etc. and pipes 5mm and less in diameter.