This passage from the NELP EES makes it pretty clear . Majority...

This passage from the NELP EES makes it pretty clear . Majority of spoil to be clean fill .

''It is estimated that approximately 6.1M m3 (in situ) of spoil would be generated for the construction of North East Link, primarily from tunnel and trench excavations. Spoil has been categorised as prescribed industrial waste or Fill Material (also commonly referred to as ‘clean fill’ in accordance with the EPA Victoria Industrial Waste Resource Guideline (IWRG) Publication 621 Soil hazard categorisation and management.
The estimated spoil volumes by spoil type are presented in Table 23-3.
The majority of the spoil is expected to
be Fill Material. However, some spoil,
notably the Silurian siltstone, would
be classified as Category C,
predominantly due to the levels of fluoride present. This fluoride is likely to be naturally occurring and so the majority of the material may be able to be reclassified as Fill Material. For this to occur, reclassification would need to be approved by EPA Victoria, through an application demonstrating that fluoride levels are equivalent to background concentrations and that historical activities in the area do not indicate any sources of this substance.''