In a general managers’s note attached to the notice of motion co-signed by Crs Greg Watson and Joanna Gash, Mr Pigg warned biodiversity credits for vegetation alone could cost $10 million or more. Species specific credits would cost even more, he cautioned.

The use of biodiversity credits underpins the notice of motion to be debated at next week’s ordinary meeting of council. The notice of motion calls on council to act as the proponent for the project and submit a new development application. 

When Motorcycling NSW abandoned the plan earlier in the year it had spent $1 million trying to get the development application approved by the Joint Regional Planning Panel.  

Mr Pigg said council in all likelihood would be required to buy land that contained the same vulnerable orchids as those found on the Yerriyong site.

“Looking at the price of credits that have been sold in the local area, vegetation similar to what is on site is costing approximately $2580 per credit,” Mr Pigg warned.

“Credits for vegetation alone could cost in the vicinity of $10 million or more.”

There would also be significant expense in the preparation of the development application, he said.

“Studies etc will be significant in the first instance and at the very least council should set a budget limitation if it adopts the notice of motion which presently has no budget cap.” 

He said the purchase of the land itself from the Crown would cost about $600,000.

Mr Pigg’s warning adds to a growing chorus of concern about the likely costs to ratepayers of picking up the project. Earlier this week, Cr Andrew Guile gave a searing assessment of the idea, saying costs would be extremely high. 

Shoalhaven Mayor Amanda Findley said on Thursday, September 21 the costs could be as high as $20 million before work even commenced.