Transport for NSW and Lake Macquarie council, along with multiple community and environment groups, have called for the company to reassess its plan to truck coal between Myuna Colliery and a site west of Eraring power station where coal from its Mandalong mine comes to the surface.

Centennial's proposal, which is being assessed by the Department of Planning, Industry and Environment, aims to rectify issues with the quality of Myuna's coal by blending the two sources to meet the standards required for use at the power station.

Up 62,500 truck trips would occur each year on a route that includes Wangi and Wilton roads to shift more than a million tonnes of coal between the two sites.

Transport for NSW said it did not offer "in-principle support" for trucking coal on public roads and asked Centennial to prove why "potential alternatives are not practicable or feasible".

"Using public roads has potential inherent traffic and road safety impacts which will be required to be addressed," the agency's submission to the DPIE said.

It highlighted multiple "deficiencies" with the proposed transport route, including the need to provide turning and merge lanes, street lighting and for a road safety audit to be undertaken "to identify any other risks and mitigation measures".

It said any proposed works would have to be completed "at full cost to the developer" and would require "sufficient lead time".

Centennial's modification report had noted, but ruled out, alternatives including building a washery at Myuna's pit top or blending coal on Origin Energy's land. Both options would utilise the overland conveyor between the mine and Eraring.

The council said in its submission that Centennial had not "fully explored or detailed" the alternatives and trucking the coal would result in traffic, noise and environmental impacts.

"If there is an alternative method for transporting the coal rather than using the public roads, this should be further explored," it said.

"Whilst the proposal will result in economic benefits due to enabling the continuation of mining operations, the proposal will result in a number of negative social impacts. These impacts have the potential to affect people's way of life, quality of life, and their health."

Origin Energy maintained its position that it had been "unaware" of the plan until it went on exhibition, but said "numerous ongoing discussions" had been held with Centennial "in relation to the future outlook of the coal quality from [Myuna]".

"Origin has not initiated the need for Centennial to transport coal via public roads," it said.

"Origin considers that the quality of coal supplied by a mine is best managed at the producing mine utilising a range of management methods including on-site blending, appropriate mining methods and deployment of technology to provide real time quality assurance."

More than 70 individual submissions were lodged during the modification's exhibition, the overwhelming majority of which objected to the plan. Five community or environment groups also outlined their opposition.

The DPIE has asked Centennial to respond to the concerns raised in the submissions, including about traffic and transport, noise, air quality and consultation.

It has also "encouraged" the company to hold talks with Origin Energy about alternative options.