Veronica Green, who would now be 82, was 38 when she was last seen on February 13, 1976.

The dig started on Monday in a bid to find the missing woman, but no items of significance were found and it concluded on Friday, Victoria Police said.

They dug up the site of a former swimming pool, removed the garden shed, concrete paths and searched below the house and the roof.

Ms Green was married and it was her husband, who has since died, who reported her missing.

Her two children were aged seven and 14 when she vanished.

"When a loved one, family member or friend disappears without explanation, it causes significant heartache for the families involved," Detective Sergeant Allan Wood said.

Police believe Ms Green had a difficult marriage, but are not certain this was a factor in her disappearance.

The detective said earlier this week new information had emerged in the past 12 to 18 months which led to the decision to dig.

"We can't rule out foul play at this stage," he said at the time.

On the day of her disappearance, Ms Green left her Ardeer home in her grey Morris Minor and drove to the Albion railway station, where she parked and caught the train to work in Melbourne.

She never returned to pick up the vehicle.

Ms Green left all of her possessions at her home and has not been seen or heard from since.

"Despite the time that has passed I encourage anyone with information to come forward," the detective said.

"It's never too late."

The detectives will prepare a brief of evidence for the coroner to determine the circumstances of her disappearance.

Australian Associated Press