The site, which will be used for manufacturing, assembly and servicing of mostly mining machinery, will serve as the Swedish company's NSW headquarters.

Sandvik expects about 600 employees to be working at the site when construction is completed and it begins 24-hour operations.

That number could rise to 750 in five years.

The development, on Masonite Road, will feature several large worksheds, a main office, warehouse, storage, motorbike shed and car park.

A training facility, amenities building and a gym and sauna will be built for employees.

The environmental assessment report on exhibition says the development boosts the economy by providing 80 construction jobs as well as the permanent staff.

"In the longer term local employment is positively affected through increased demand for goods and services by staff and visitors," the report said.

"The proposal will enable a range of industrial activities to be located within the vicinity of the site . . . [and] attract a number of supporting industries to the area."

Sandvik plans to replace and upgrade a section of Masonite Road as part of the proposal.

Although the site will operate 24 hours a day, testing of loud equipment will take place during daylight hours only.

About 13.5 hectares of the Masonite Road site will need to be cleared for the development. Sandvik has offered land at Duns Creek to offset the clearing.