Police began a new search of the former home of missing Northern Beaches woman Lyn Dawson on Wednesday, with detectives from the homicide squad arriving at the Bayview property around 9am.
“We have a good understanding of this particular property," police told media outside the house. "We had radar penetration looking at the ground. It is a complex block of land because it's largely rock, so digging is not easy.”
Lyn Dawson has been the subject of true crime podcast The Teacher's Pet, which has catapulted her mysterious disappearance in 1982 back into the public eye.
Two inquests have found that Dawson was likely killed and that a "known person", since identified by the state coroner as her husband Chris Dawson, should be prosecuted. The DPP decided there was insufficient evidence to lay charges that would result in a prosecution.
At the time of her disappearance, schoolteacher Chris Dawson was in a sexual relationship with his teenage student Joanne Curtis.
Curtis moved into the Dawson family home shortly after Lyn's disappearance, and Dawson did not report his wife missing to police for nearly six weeks.
Dawson and Curtis later married, separating six years later. He denies any wrongdoing.
In 1991, New South Wales police re-opened an investigation into Dawson's 1982 disappearance.
In 1999 police dug an area near the pool at her former Bayview home and discovered part of a cardigan. One episode of The Teacher's Pet podcast focused on the police failure to dig up the "soft soil" beneath Dawson's daughters' bedroom windows.
New South Wales police presented the DPP with new evidence about the case in April of this year. The evidence is still being reviewed.
On Tuesday Dawson's nephew, David Jenkins, said on Twitter that he hoped the investigation would lead to the discovery of his aunt. "We need to treat Lyn with the dignity that has been denied for so long and bring her home to rest," he wrote.