1.3 million tonnes is a bit much. Some figures I've found for...

1.3 million tonnes is a bit much.

Some figures I've found for Melbourne Metro spoil is:
2 million cubic meters of spoil in total, of that 1.3 million should be clean fill and and an estimated 221,000 of PASS. Read page 20-12.

https://www.google.com.au/url?sa=t&...FjABegQIARAB&usg=AOvVaw0E2UnwH325y2NQgP9oyJci

Several scenarios could play for NAG if they won a subcontract to dispose of spoil.
1. NAG could take all 2 million m3 (PASS included) at an average $ value.
2. NAG could take only the PASS at a higher $ rate.
3. Any combination of the above.

Option 1 would guarentee Lendlease disposal of all spoil including PASS in accordance with EPA requirements 24/7 in all weather with no stoppages. I'm not sure they would even need to continuously test the 2 million cubics of spoil for PASS as it would all go in the same hole and be be safe underwater.