The three-storey building at suburban Sturt was closed in July after officers heard "a rumble" and saw structural movement in the western end of the site.

Assistant Commissioner Paul Dickson says the cracking was caused by soil movement and has not affected the building's structural integrity.

"Full independent structural and engineering assessments have been undertaken which found the major structural elements of the building are sound," Mr Dickson said on Wednesday.

"However there was damage to some lightweight internal elements such as walls and door frames.

"In the wake of the reports, a plan was developed for the undertaking of repair work to allow for a return of services and workers to the building."

The station will reopen on Wednesday next week.

Australian Associated Press