The contemporaneous actual critical path or a retrospective as-built critical path on an energy from waste project?

UK - South West | Power & Renewables | Expert Services

Vantage Three was appointed to provide independent unbiased opinion regarding the incidences and causes of critical delay on an energy from waste plant. The project involved civil, building and process works associated with the provision of a new 240,000 tonne/year energy from waste plant burning mixed municipal and commercial waste.

Vantage Three's delay expert determined the actual critical path in the context of an As-Planned vs. As-Built Windows analysis with reference to the available facts. In that regard, competition for the longest path was typically between the process hall workstream and the suspended incinerated bottom ash facility workstream.

The opposing expert took a view that the only relevant critical path was that at the point of completion itself - that is to say, if a workstream was not critical at the end then it could not have caused critical delay during the project.
The contemporaneous approach taken by Vantage Three's delay expert - to determine what was critical at any particular time - was preferred.