Shelly-Anne Bacsu (bah-shoo) was last seen on May 3, 1983, just outside of the town of Hinton.
Police say they still hope someone will come forward with information to help solve the mystery of the 16-year-old's disappearance.
The girl's mother, Muriel Bacsu, says she believes someone in the town knows what happened to her daughter and will speak up to end their family's nightmare.
Bacsu says RCMP contacted her last month when remains were found by people riding all-terrain vehicles near the hamlet of Brule (broo-LAY'), a community just west of Hinton.
RCMP say the remains, which may not be human, are still being tested and have not been linked to the girl.