A private investigator searching for Anne Hill, 16, made a public plea for help in the case.
The Casady High School student vanished April 11, 2014 from Edmond and is feared dead.
In the last nine months, several helpful tips have come into the offices at the Center for Search and Investigations of Oklahoma (CFSI OK), but none have taken investigators to Hill's body.
9/24/2014 Related Story: Investigators Search For Clues In Disappearance Of Anne Hill
Darcie Parton-Scoon said she hopes releasing a new set of clues about the area will give them new leads in the case.
"Most of the areas have been searched [in rural Edmond], in addition to the apartment where she was last seen and where her car was found," said Parton-Scoon.
Investigators said they have searched 2,000 rural acres and covered more than 200 miles without success.
View the full request for public assistance released by investigators.
"Unless we find her, I consider it a failure," she said.
Parton-Scoon claimed they will not give up, especially considering the arrests of Chadd Raymond,16, and Chloe Thomas, 17. The arrests came with a confession and some specifics about where the pair allegedly dumped Hill's body after she was killed. Both were criminally charged in her murder.
From the confession, Parton-Scoon said the areas of concentration are off I-40 west of Oklahoma City and I-35 south of Oklahoma City, although the eastern and northern portions of the highway have not been ruled out.
"We know at the exit there could possibly be a man-made rock formation," Parton-Scoon said. Specifically, Parton-Scoon said they are looking for a field in a wooded area with oil or pump sites nearby. "Between the drive to the well site and from the exit, there could be a structure that looks like a white mobile home."
She said she is hopeful the notable features will stand out to those who live near the area.
If you have information matching the description contact investigators by email at firstname.lastname@example.org or by phone at (404) 500-9376.