A Roads and Maritime Services spokesperson said Wilkinson Murray had been engaged to carry out the post-construction assessment after the $230 million 14 kilometre upgrade, jointly funded by the Australian and NSW governments, opened to traffic in September 2017.

"Noise monitoring was carried out in August 2018 at various locations throughout the project to compare actual noise levels against the predicted levels used in the project design," the spokesperson said.

"This involved placing an automated noise logger at 10 residential locations to continuously measure noise levels for 12 days, with some attended monitoring also carried out at each location.

"At the same time, traffic counts were taken at 12 locations to measure vehicle volumes and speed.

"The monitoring results were used to examine noise mitigation currently in place and to determine if further measures are required.

"The assessment found operational noise levels closely matched the predicted noise levels on the project."

As part of this assessment, four properties were identified for further noise mitigation treatment.

The Roads and Maritime spokesperson said project staff will be contacting individual property owners to discuss their options.

"The noise report has been reviewed by the NSW Environment Protection Authority and Department of Planning and Industry to ensure regulatory requirements have been met," the spokesperson said.

The report is available to download on the project website at www.pacifichighway.nsw.gov.au or by contacting Roads and Maritime on 131 782.

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