This REF has been prepared to assess the potential impacts of the proposed rehabilitation of the Mid-Western Highway between 53.18 to 56.38 km west of Bathurst, at Carcoar. It presents details of the proposal, assesses the existing natural and social environments, describes the potential impacts on the environment and presents safeguards to minimise and/or remove these identified impacts. Total length of the route is 485 km. Primary deficiencies along the route are narrow formation, lack of sealed shoulders and poor drainage.