Bowen teenager Rachel Antonio went missing in 1998.
Bowen teenager Rachel Antonio went missing in 1998. Contributed

What is the chance of finding evidence after 20 years?

POLICE can't confirm when, or if they will begin digging up the Bowen tip in search of the remains of missing teenager Rachel Antonio.

Maps of the Bowen tip in 1998 were not "evidence" of where missing schoolgirl Rachel Antonio was but "information" police would follow-up, Mackay Detective Inspector Nikki Colfs said.

Det Insp Colfs, the officer overseeing the case, said police still needed to determine what evidence they would be looking for before digging up the tip.

Rachel's parents have long suspected their daughter's body might be in the tip but it was never searched after she went missing in April 1998.

Their suspicions are based on the limited amount of time a killer would have had to dispose of Rachel's body and the belief it may have been put in a skip bin.

Former tip manager Hugh Smith provided police with maps of the tip from 1998 after it was revealed during a Courier Mail podcast late last year he had recently discovered his old tip diaries.

The re-emergence of the maps has led to police examining the "feasibility" of digging up the tip and looking for more evidence.

On Wednesday, Det Insp Colfs visited the Bowen tip with Mr Smith and forensic experts.

She said the feasibility wasn't about the cost of digging up the tip but the chance of finding evidence almost 20 years after Rachel had gone missing.

"Cost is never a consideration with it comes to someone's life," she said.

Police will have to determine the area of the excavation site, what evidence they are looking for, the likelihood of it being there and if the evidence would have survived 20 years in the ground.

"Look, my impression, and I'm not an expert, it would be a fairly difficult job," Det Insp Colfs said.

"There is a lot more involved in knowing the area and the equipment that could be used.

"It is a lot more complicated than just putting an excavator in."

She didn't give a timeline of when the decision to dig up the tip or not would be made.

A coroner last year found Robert Hytch had killed Rachel and hid her body. Hytch is appealing the findings in an ongoing case.

Det Insp Colfs said police did not intend to speak to Mr Hytch about the new information at this stage.