Emergency crews were called to Railside Avenue in Bargo at about 4.40pm last Thursday, following reports a pedestrian had been hit at the work site.
The driver, a 55-year-old man, was not injured and was taken to hospital for mandatory testing.
A crime scene was established and an investigation into the circumstances surrounding the crash began.
Police were told on Sunday afternoon that the woman had died in hospital.
SafeWork NSW is investigating.
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