The deal is attractive to council as the coal wash reject material and soil would be delivered and provided at no cost to ratepayers – as it also benefits the colliery to get rid of the material for free.

Councillors at Monday’s meeting agreed to proceed with an attempt to use the mixed material for “capping” the landfill – covering the site with a thick layer of topsoil or other material.

They voted to not send this to tender, not wanting to miss a chance to save $224,000 while reducing truck movements and reusing waste material for rehabilitation.

The tip was closed in 2012 in a move council said would better care for the environmentally sensitive area. The landfill was not lined so there was the threat of leaching into creeks that feed to the Royal National Park nearby.

Peabody’s Metropolitan Colliery offered to provide the materials for the capping in the form of coal wash reject material from the mine.

This material was not up to the standard required by the Environment Protection Agency, so it was stalled.

But the report from council staff recommended accepting an offer to cap the site with a combination of coal wash and clean soil that had been dug up during mine-related excavation. Council’s plan depends on this mixed material passing the EPA’s testing standards.

It will be some time before the results of the testing are known, delaying the rehabilitation work.

Council staff who recommended the mixed-material plan noted it would involve less kilometres to be driven by trucks bringing it in.

The downside of this plan was that it would delay letting of the contract to a principal contractor for the rehabilitation job.

A council spokesman said decisions on the future use for the site would be made several years down the track.

“Any use of the site would be determined by a future council,” he said.

“The remediation of the site will probably need between 5 and 10 years to see how it performs.

“This remediation work would then need to be assessed prior to a decision on the future use.”