The Australian government said that geotechnical works at the proposed airport at Badgerys Creek have begun.
Deputy Prime Minister and Minister for Infrastructure and Regional Development Warren Truss also said that a detailed plan for the airport would be developed by the end of the year.
Residents in the area would be expected to inspect the environmental impact and give its statement within months, according to The Sydney Morning Herald.
Truss said: "The Western Sydney airport will be among the nation's most impressive civil engineering projects over the next decade. The Commonwealth-owned land at Badgerys Creek is a large site of around 1,700 hectares and extensive investigation is required to assist in planning for the first stage of an airport.
"A team of engineers will be at Badgerys Creek to profile the subsoil and rock at several locations over the next six weeks."
The proposed airport that will cost an estimated $6-$8bn is supposed to replace the existing Kingsford Smith Airport in Sydney.
A part of the geotechnical work, more than 100 boreholes of a depth up to 40 metres will be excavated while earthmoving equipment will dig pits five metres in depth.
Extensive geological surveys will be carried out to understand rock density, the samples of which, will be analysed by the end of the year.
"In April last year the Australian Government ended decades of uncertainty with our decision that Badgerys Creek will be the site of an airport for Western Sydney. The airport will be a major boost for the local economy, creating thousands of jobs during construction and a pipeline of tens of thousands of jobs once the airport commences operation.
"Work is well underway to develop a commercial proposal for an airport which could be expected to operate from the mid-2020s."
Image: A map showing indicative geotechnical investigations at the Badgerys Creek airport site. Photo: courtesy of Department of Infrastructure and Regional Development, Government of Australia.