One of those is 53-year-old Steven Hadaway, a former Marine. And nearly every day his brother John Hadaway comes to the scene of the disaster to help search for him.
John says he's being realistic about his brother, but there's still so much left to do - and he still doesn't have the answers he seeks.
Steven Hadaway wasn't one of those living on Steelhead Drive. He was simply on a job, installing satellite TV, when the slide hit.
"I dropped to my knees, and I thank God that he took him fast," says John Hadaway. "My brother's still out there, and there are three other people beside him."
And for three weeks, John has been there, too.
"If you've been in that muck and you understand, it is what it is - it's downright horrible," he says.
On Thursday, John tried to work in Puyallup. It didn't work.
"I feel like I'm abandoning my brother by being home," he says.
John will get another chance to help the search again this weekend. He says realism is taking hold, but he and the family believe Steve Hadaway will be the last to be found - a Marine to the end.
"He wants everyone else to be safe. He wants everyone else to be with their families. And that's just who he is," says John.
John isn't part of the National Guard or firefighters. He's just a man missing his brother, and honored that so many others have come to help.
"All we have to say is thank you. That doesn't even scratch the surface - doesn't even scratch the surface."
Because closure - finally - may come.
"They call me whatever they want, but they know me by 'Steve's brother,' because I'm OK with that. Because that's exactly who I am," says John.
Besides Steven Hadaway, the three others still missing are Molly "Kris" Regelbrugge, 44; Steve Harris, 52; and Theresa Harris, 53.
John said he has heard the discussions about repairing and reopening Highway 530, but he wants to make sure everyone is recovered from the debris fields before a single car goes through there again.