SOIL testing is underway at the site of Bendigo's GovHub.
It comes as the city plans for the day its staff vacate the offices at Lyttleton Terrace, where a 1000-desk building will be constructed.
Environmental and geotechnical investigations started on Monday and are expected to continue until Saturday.
Preparations for the sale of the land are still ongoing.
Meanwhile, the city has been arranging where its staff will be based during the construction phase.
It will need to vacate its main office and three other buildings on the site by April, with demolition expected to start mid-2020.
The customer service centre is expected to relocate from the city's main office at Lyttleton Terrace to its Hopetoun Mill office either in late November or early December.
The city intends to lease the upper level of the Fountain Court complex from the Bendigo and Adelaide Bank to house the rest of the staffers shifting from the Lyttleton Terrace site - about 200 workers.
It plans to lease the site for three years from January, with the option to extend or exit as required.
The $90m state government project is expected to be completed by mid-2022.
Bendigo council considered 16 sites when searching for temporary offices.
"Independent market analysis was also commissioned to assess the rental costs," corporate performance director Andrew Cooney said.
He said expenses associated with temporary offices were factored into the city's costings for its involvement in the project.
Mr Cooney said work would soon start at the Hopetoun Mill office, at Hopetoun Street in Bendigo, to make way for the customer service team and new technology intended to streamline the customer experience.
"We look forward to introducing some supported self-help kiosks and a concierge-type service to decrease the time spent in a queue, which will be similar to how we will work when we move into the GovHub," he said.
"We will ensure plenty of information is shared with the community in the coming months so as they will know when we are moving and how to find us."
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