A preliminary environmental assessment for the multibillion-dollar Terminal 4 coal-loader project reveals an option to load coal on the north and south sides of the Hunter River.

The proposal represents a significant expansion of coal-loading activities in the port, which have previously been constrained to the northern side of the river.

It has also provided fuel to the supporters of Nathan Tinkler's proposal to build a coal-loader on the BHP industrial site at Mayfield.

The two T4 berths on the southern side of the river would be fed by a conveyor running parallel to Mayfield's Tourle Street bridge, to transport coal from Kooragang Island.

Port Waratah Coal Services spokesman Matthew Watson said there was an onus on the organisation to ensure multiple berthing options were considered so future exports could occur efficiently.

Other berthing options, which would be serviced by conveyors, had been proposed for Walsh Point.

"These are only preliminary ideas and would need to be subjected to the rigors of industry, community and government consultation," Mr Watson said.

"We are also bound by an exhaustive environmental and planning assessment process."

Newcastle MP Jodi McKay said she had been briefed on the options.

"My understanding is that this is a bit of a fishing exercise by them (coal services) to see what is possible in relation to T4," she said.

"I think it's important that the community is made aware of this and is consulted all the way through because wherever they go it's going to be controversial."

The Kooragang Island wind turbine has stood on land leased from the Newcastle Port Corporation since 1997.

However, a map showing the location of the proposed ships' swing basin reveals the turbine could be squeezed out.

Ausgrid (previously EnergyAustralia) and Port Waratah Coal Services confirmed yesterday that they were in discussions about the implications of the swing basin on the wind turbine site.

A Port Corporation spokesman said the swing basin was essential to the development of the port.

"The exact location of the swing basin on the south arm is being examined," he said.