1. PVC Ducting System needs 7 stages of working while COD only needs 3 working stages.
2. Above dimension is without consideration of man working space inside the excavated trench, but only vertical cut.
3. Above dimension does not show slope but vertical cut from bottom.
4. PVC ducting system needs 3 mobilizations:
1) Outer duct in the initial stage.
2) Cleaning, Inspection of installed Outer Duct Line and Inspection & Test of installed Outer Duct Line.
3) Inner duct for insertion.