Cadaver dogs have been brought in to search for the remains of Bathurst teenager Jessica Small, after police received new information regarding her abduction.

Homicide police investigating the disappearance of the 15-year-old in 1997 will today begin excavating an isolated area near Bathurst in the hope of uncovering further evidence.

In addition to the dog squad, homicide police will be assisted by officers from the Australian Federal Police, who will use ground-penetrating radar to pick up deviations in the soil in the area to be searched.

The officer in charge of the investigation, Detective Sergeant Peter Smith, said the federal police unit has the most specialised officers in Australia doing this type of work.

He said the excavation was the result of new information received by police from a member of the public.

Jessica and a friend, Vanessa Conlan, were trying to hitch-hike home from the Amuse Me Games Arcade in Bathurst when they got into a white VK or VL Holden Commodore sedan.

When the male driver allegedly tried to assault them in the car, Jessica's friend managed to escape and alert nearby residents.

Jessica has not been seen or heard from since. Detective Smith said investigators believe Jessica was murdered shortly after her disappearance.

Police have new information that a car similar to the one Jessica was abducted in was seen in a riverside area at O'Connell, about halfway between Bathurst and Oberon.

Police now believe the car was seen driving along the Great Western Highway at Kelso with its headlights off.

They believe the car then turned into the O'Connell Road, travelling towards O'Connell.

"We have conducted extensive inquiries in recent years and new information suggests a car similar to the one Jessica was abducted in was observed in a riverside area at O'Connell just hours after the abduction," Detective Smith said.

"Detectives were told the car was driven to a secluded area near the Fish River, off the O'Connell Road, O'Connell, halfway between Bathurst and Oberon. The car remained parked there for a considerable period of time."

He said the excavation was expected to take two days, and police have not ruled out the possibility of finding Jessica's remains there.

Detective Smith said the new information was heartening for investigators, and again encouraged anyone with information on Jessica's disappearance to contact homicide police or Crime Stoppers.

"I think the reality is people now realise she's been missing for 15 years, and she hasn't run away," he said.

Police say they are seeking information about a male employee of the Oberon Timber Mill, who was present at the Amuse Me amusement centre on the night of Jessica's disappearance and may be able to assist police.

They would also like to hear from a witness who previously told police about a former workmate in the Bathurst area who owned and then disposed of a white Holden Commodore about the time of Jessica's disappearance. That vehicle was possibly involved in a car accident, police said.

The Western Advocate,