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Nearly five years after David Bass found the remains of a murdered Virginia Tech student on his farm, the 75-year-old looks out at his 700-acre property and wonders if the body of another missing woman lies somewhere out there, in a shallow grave, hidden within dense woods or left in some remote ravine.

The sprawling farm in Albemarle County, dubbed Anchorage Farm, was searched by police in the disappearance last month of University of Virginia student Hannah Graham. While Bass claims it’s unlikely the 18-year-old sophomore is there, he said his property and the many other farms surrounding it cannot be ruled out.

"Is there a place somewhere where we haven't been? I mean, of course," Bass said of the search for Graham, who was last seen Sept. 13 after leaving a party in Charlottesville.

On the morning of Jan. 26, 2010, Bass discovered the skeletal remains of 20-year-old college student Morgan Harrington while riding his tractor to inspect fences on his farm. Harrington had disappeared three months earlier, on Oct. 17, 2009, after leaving a Metallica concert on the UVA campus in Charlottesville. Her badly decomposed remains, which Bass first mistook for a deer, were found 200 yards off a public road on his property, 10 miles outside of Charlottesville, he said.

"It takes a long time to see these things in rural places," Bass told FoxNews.com, noting that his farm consists of open fields as well as heavily wooded areas, ravines and a small mountain. "Morgan went missing in October. It took me till January to find her. Most of southern Albemarle is like my farm."

Authorities announced last week that a forensic clue linked Harrington to 32-year-old Jesse Leroy Matthew Jr., the prime suspect in the disappearance of Graham. Matthew was apprehended in Texas last month and charged with abduction with intent to defile in the case of Graham, a UVA sophomore from Alexandria, Va., who has not yet been found, despite expensive ground searches and the assistance of the FBI. Investigators had previously said DNA from Harrington's attacker matched a perpetrator in an unsolved 2005 sexual assault in Fairfax.

Harrington, from Roanoke, was last seen by her friends as she was leaving UVA's John Paul Jones Arena in search of a restroom. When friends later called her cell phone, Harrington said she'd been locked out of the arena and would find a ride home. Witnesses later reported seeing a woman matching Harrington's description walking along a bridge not far from the arena. Matthew, a hospital worker, had a taxi license at the time Harrington disappeared.

While police released few details about Harrington's death, her family said in 2010 her murder had been violent, with several bones broken. She had also been raped, they said.

Graham also disappeared after becoming separated from her friends. Surveillance video showed Graham as she walked or ran alone past a bar and a service station, then onto Charlottesville's Downtown Mall. She sent friends a string of text messages, saying she was lost after leaving an off-campus party, according to police. Witnesses later told detectives she was seen with Matthew at a bar.

On Saturday, Graham's parents issued an emotional plea for her return.

Sue and John Graham, of Alexandria, issued a written and videotaped statement describing their daughter's disappearance as a nightmare.

"Somebody listening to me today either knows where Hannah is, or knows someone who has that information. We appeal to you to come forward and tell us where Hannah can be found," Sue Graham said in the taped statement.

"John has already said that this is every parent's worst nightmare ... Please, please, please help end this nightmare for all of us. Please help us to bring Hannah home," she said.

Virginia Department of Emergency Management coordinators plan to have more than 70 percent of Albemarle County searched by the end of this week. Investigators are using tracking dogs to scour rural parts of the county that have not already been checked. Bass, who has given police full permission to examine his farm, said he's not aware of any plans to re-search his property.

The Harrington family is offering a $100,000 reward for information leading to the arrest and conviction of the person or persons responsible for their daughter's murder. The band Metallica is offering an additional  $50,000, bringing the reward to $150,000 for information leading to the arrest and conviction of the person or persons responsible.

In the Graham case, meanwhile, authorities are offering a $100,000 reward for information leading to her safe return.

Anyone with information on Hannah Graham's whereabouts is urged to call the Charlottesville Police Department tip line at 434-295-3851 or email CPDtips@charlottesville.org.