A forensic anthropologist with the military's Joint POW/MIA Accounting Command, Moore decides where to dig and for how long in conditions plagued by erosion, scavenging and even bone-eating acidic soil.
For the 1,800 American families who long for answers and a small piece of their loved ones to bury, he is often the last hope.
"Vietnam was the war of my generation. So many paid the ultimate sacrifice to come over here and wage war for American policy of that time and, of course, it wasn't a very happy ending," says Moore, 53, smoking a Marlboro while perched on a thick root overlooking an excavation site.
"This is just one way I can pay my dues."
With a draft number high, Moore volunteered to fight in Vietnam in 1968. But he was turned down when doctors realized he had only 10 percent of his hearing -- his deafness the result of experimental antibiotics used to treat pneumonia as a baby.
The son of a doctor and a nurse, Moore yearned to do medical work. But he was rejected by medical schools, and forensic anthropology became the answer.
In 1992, after earning his doctorate, Moore joined the Hawaii-based team, which sends men and women from the Army, Navy, Air Force and Marines in search of remains from as far back as World War II. Anything recovered is sent to Oahu where experts, including Moore, work to match DNA to lost soldiers.
"He's something of a legend to everyone," says Sardiaa Plaud, a civilian at the lab. "Everywhere you go, people know him."
All of the easily accessible Vietnam War sites have been picked clean, yielding more than 700 identified sets of remains since 1973.
The remaining locations are daunting. Some are situated on 65-degree inclines that require searchers to strap themselves to trees and form bucket brigades, passing soil to be sifted through metal screens in search of bone fragments.
The site on the Laotian border in central Vietnam is at 1,800 feet, so high the villagers call it "Khong Troi" or mountain with no clouds. Accessible mainly by helicopter, it's just off old Route 10, which once served as a North Vietnamese supply line.
Moore rattles off the history of the site, where two men in a twin-engine Cessna were shot down during a reconnaissance mission in 1968. Human remains have been recovered here, but the team of Americans and Vietnamese will not leave until the 120-by-120 foot area is fully excavated.
"They always give the tough sites to Hoss," said Army Capt. Octave "Mac" MacDonald, the recovery team's leader from Baton Rouge, La., referring to Moore by his nickname.
"I think that's pretty much because he's the best."
At 6-foot-4 and 270 pounds, Moore, of Stilwell, Kan., is a source of curiosity.
With his can of Copenhagen snuff, Cambodian scarf and wide-brimmed straw hat, one U.S. team member described him as a cross between Indiana Jones and the Marlboro Man.
He's worked hard to cultivate strong bonds with residents, who often recognize him in the remotest places, calling out a friendly "Hoss!" or "Doc Moore!"
"To get along with your counterparts, no matter which culture you're in, you break bread with 'em, drink their whiskey and eat their food," he says, laughing. "I've eaten about every kind of critter they have in this country, from four-legged animals like porcupine and raccoons to iguana, cobra, python."
And for Moore, living in the open is preferable to the cities and highways at home. He's the only one in the group who sleeps on a cot under a mosquito net instead of in a tent. Still, he admits the months away from his wife, Ginny, their three children and six grandchildren aren't easy &3151; especially since he's lucky to get home twice a year.
"It does get lonely, but then you've got to improvise, adapt and overcome," he says. "I never went to a deaf school. I went to public schools all my life it wasn't easy."
His experience, sense of humor and tough-as-nails attitude have created easy bonds with team members who are often less than half his age. They quickly learn the only way to communicate with Moore is to talk while looking him in the eye his hearing aid is useless in the jungle's soupy humidity.
But beyond his larger-than-life persona, it's his professionalism and expertise that earn Moore the most admiration.
"He's kind of the grand old man on the mountain when he's there," says Lt. Col. Ty Smith, commander of the U.S. MIA office in Hanoi. "I'm the boss, but he mentors me and I want him to."
Moore says he gets immense satisfaction from helping return lost soldiers to their families, and he says his work also sends a message to soldiers in Iraq: No matter what happens, someone will bring them home.
But Moore says perhaps the biggest benefit comes from bandaging the wounds of his generation's war.
"It brings closure (to America) for part of the healing process," he said. "Eventually, we'll get the issue resolved and that chapter will be closed ... hopefully."
By Margie Mason