Simpson-Deane was reported missing after her first period class ended at Cary High in Sept. 19, 2000.
Authorities said a tip led them to an old well in rural Nash County last Thursday. A backhoe was used to dig up sections of the old, abandoned well.
The remains that were recovered were taken to the state medical examiner in Chapel Hill for identification and to determine the cause of death.
Cary Police will not say exactly how she died, but they are treating it as a homicide.
"Everybody says things like, 'You have closure,' but what is closure because you know where she is. I know that she is in a better place now, you know, she does not have to deal with this world as it is today," said Curtis Deane, Amanda's father.
Simpson-Deane's family is planning a memorial service on Thursday. It will take place at the Mount Zion Missionary Baptist Church on Chapel Hill Road in Cary. The service starts at noon.
"We're all coming together to remember her. We'll always remember her anyway. She's a good girl. Everybody she met, you know, was affected by her," said Deane.
Cary police have not named any suspects, but they said one of the last people she was seen with is Jevon Ward. Ward is already in federal prison charged with allegedly attacking a Cary police officer, hijacking two cars and leading police on a high-speed chase through Raleigh.
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