Dozens of police will this morning converge on an area of bushland where they believe the body of missing mother-of three Samantha Murphy has been hidden, after revealing new details about secret searches for her over the past six weeks.

The 51-year-old was last seen leaving her home on Eureka Street in Ballarat, Victoria, to go for a run in the Canadian State Forest on the morning of February 4.

On Wednesday morning, Victoria Police Missing Persons Unit Detective Inspector Dave Dunstan told a media pack search crews expected to enter treacherous bushland near Grenville, south of Ballarat, as soon as the weather permitted.

The region has been bombed with heavy rains, but are expected to clear before midday. 

The search areas are believed to be taking place in mountainous terrain west of Enfield Plantation, which has been previously searched over the seven months since Ms Murphy went missing. 

A large police force has gathered at the Grenville Recreation Reserve, with officers seen preparing to head out with the aid of horses, dogs and motorbikes. 

Detectives from the Missing Persons Squad were joined by specialist officers from NSW Police and their Australian Federal counterparts on Tuesday in the latest large-scale search.

Inspector Dunstan said police had in reality been searching in the area on-and-off for the past month-and-a-half. 

‘There are a number of areas in which we are actually searching in a number of different areas,’ he told reporters gathered at the meeting point. 

Inspector Dunstan said search crews faced dangerous conditions, which had only been compounded by the bad weather. 

‘The danger is there are a lot of mines here as well and that’s one of the reasons we’ve brought out Search and Rescue,’ he said. 

‘There are a lot of unidentified mines … so it’s super dangerous.’

Police are understood to be searching different areas spanning up to a three kilometre radius of rugged terrain. 

Up to 45 officers are expected to join in the search, with a select number of media representatives to be taken into the area sometime on Wednesday. 

It remains unknown how long police will remain in the area, but it is understood detectives remain hopeful the latest search will result in the recovery of Ms Murphy’s body. 

Police have launched multiple searches in bushland since February as part of their extensive investigation into Ms Murphy’s disappearance.

Detectives found her mobile phone near a dam in Buninyong, 10 minutes from her home in June.

The phone was undamaged and in near-perfect condition.

The new search in Grenville is less than 15km from Buninyonng.

Ms Murphy’s body has never been found.

She was last seen leaving her home on Eureka Street to go for a run in Canadian State Forest on the morning of February 4.

A month later, police charged 22-year-old tradesman Patrick Orren Stephenson with the murder of Ms Murphy at Mount Clear on the day she went missing.

At his last court mention last month, prosecutors asked the court to adjourn the committal mention for 12 weeks to allow them to go through a brief of evidence which contains ‘extensive’ CCTV.

Stephenson remains in custody and is expected to reappear in court on November 14.

He is the son of Orren Stephenson, who played 15 AFL games for Geelong and Richmond between 2012 and 2014.