The REF assessment detailed the project, assessed the potential environmental and social impacts associated with the construction and operation of the project and identified management measures to avoid, mitigate or manage potential impacts.

The project is set to deliver a dual-lane highway through Raglan, which will help improve travel efficiency with wider roads and safer turning opportunities.

Minister for Regional Transport and Roads and Bathurst MP, Paul Toole, said the project has official planning approval to proceed thanks to the release of the REF assessment and construction will proceed once the necessary property acquisitions have been made.

"Once complete, this upgrade will provide motorists with better access to Bathurst airport, an improved and longer-lasting road surface and increased safety, especially at intersections," he said.

"We are glad to be powering ahead with this and other vital infrastructure projects, because we understand their long-term value to local communities.

"The NSW Government has invested $30 million as part of the Great Western Highway upgrade because we remain committed to delivering a safer, faster route from Sydney to the Central West."

The project will see a 3.6-kilometre stretch of the highway, beginning at the Ashworth Drive roundabout in Kelso and ending at Ceramic Avenue east of Raglan, upgraded.

The highway will also included two lanes travelling eastbound for the entire length of the project and two lanes westbound from Napoleon Street.

In response to public submissions and as part of further design development since the community drop-in sessions, significant changes have been made to the original concept design including installing traffic lights at PJ Moodie Drive and Eugenie Street intersection and a flood detention basin north of Nelson Street and an enhanced drainage system across the highway at Nelson Street.

For more information on the project and for a copy of the REF assessment, visit www.rms.nsw.gov.au.