The 100-metre-deep pit looks set to receive up to 1.5 million cubic metres of dirt and rock spoil from the construction of the NorthConnex motorway tunnel. The disused pit sits on the doorstep of Hornsby. Credit:Hornsby Council An environmental impact statement released for the plan says the former quarry has emerged as one of the preferred options to receive the excess soil so the land can be turned into public parklands. Hornsby Shire Council paid $26 million for the quarry in 2002 only to find the pricetag to make the land stable and usable was about three times that amount. The council has since recovered $9 million by arguing in court that the land was overvalued but only this year did residents finish copping a 10-year rate levy to pay off the hole.

While everyone seems to agree the quarry must be filled and there are hopes of turning it into the "Centennial Park of the North", the plan comes with a big catch. An artists impression of the park that could be built when the former quarry is filled. As Hornsby Liberal MP Matt Kean put it: "One truck movement every two minutes, 10 hours a day, for five and half days, for two and a bit years." At the project peak there would be up to 70 trucks travelling through Hornsby every hour from the tunnel excavation site about four kilometres away, according to the environmental assessment. Hornsby MP Matt Kean has campaigned for the Hornsby hole to be filled so it can be turned into public parkland. Credit:Guy Sherlock

The tunnel will eventually link the M1 Pacific Motorway at Wahroonga to the Hills M2 Motorway at West Pennant Hills. The work to fill the pit would be carried out between 7am to 6pm Monday to Friday and 8am to 1pm on Saturday for 33 months. Resident Lucy Bal who lives near the quarry, worries the noise and heavy traffic could become unbearable. "To have trucks every few seconds - you've got to be joking. It's going to be a complete disaster," Ms Bal said. "It won't just be local residents that will be affected by it, it will be the whole area. The whole thing is just awful."

Some residents have called for an underground conveyor belt to carry the soil to the quarry, but the assessment found this would be time and cost-inefficient and require substantial excavation and demolition. Mr Kean said the disruption would be significant but justified by the final result. "This is a problem that has plagued our community for over a decade. We paid $26 million for a big black hole which nobody is able to access or use," he said. "The opportunity to turn into the people's park is something too good to pass up." Hornsby mayor Steve Russell said he was confident the council would have the funds to turn the quarry into parklands by the time it was filled.

"The residents that live quite near it are the ones who will be affected the most but what we hope they can do is see the end picture," Mr Russell said. "They are going to be living on the edge of a beautiful, wonderful park in due course within a few minutes of their houses." The proposal is open for public comment but pending planning approval the filling is expected to start late this year.