Oso, Washington (KING5) -- The search area at the Oso landslide is now considered contaminated due to sewage and chemicals. Searchers on Tuesday donned protective suits.
The number of people killed in the March 22 landslide rose to 28 Tuesday afternoon; two more bodies were identified, bringing the number victims who have been positively identified by the Snohomish County medical examiner to 22.
Managers working the scene said Tuesday Highway 530 is in worse condition than first thought.
"The power of the slide came down with so much energy and just wiped out the highway bed and there is nothing left. It's just fill," said Steve Harris, Division Manager.
Related: Remembering those lost
Water from the Stillaguamish River that's trapped at the dig site is receding thanks to clear, dry weather over the last two days.
Geologists are on scene, helping point searchers in the direction where bodies would most likely be located based on the direction of slide debris.
The Snohomish County Sheriff's Office Major Crimes Unit's list of people presumed missing was at 20 Tuesday afternoon, reflecting the office's most recent updates.
The Sheriff's Office said detectives carefully reviewed each of the missing person cases based on available information and conversations with family members.
"To have released a list earlier of 90 to 100 names would have been irresponsible," Snohomish County Executive Director Gary Haakenson said Monday afternoon.
"The Sheriff's Office hasn't released these names without some pause," he said. "We want to do all we can to find them and put some closure in place for their families."
The Sheriff's Office asked that anyone who should not be on the following list call the Sheriff's Office tip line immediately at (425) 388-3845.
1. Dequiletts, Ronald M., age 52, Arlington and Bothell
2. Durnell, Thomas M., age 55, Steelhead Dr., Arlington
3. Gullikson, Bonnie J., age 91, SR 530 NE, Arlington
4. Gustafson, Mark J., age 54, Steelhead Dr., Arlington
5. Hadaway, Steven N., age 53, Steelhead Dr., Arlington
6. Halstead, Jerry L., age 74, Steelhead Dr., Arlington
7. Halstead, Gloria J., age 67, Steelhead Dr., Arlington
8. Harris, Denver P., age 13, Steelhead Dr., Arlington
9. Harris, Steve, age 52, Arlington
10. Harris, Theresa, age 52, Arlington
11. Miller, Larry, age 58, Arlington
12. Miller, Sandra, age 64, Arlington
13. Regelbrugge, Molly K., age 44, Steelhead Dr., Arlington
14. Ruthven, Katie, age 35, Steelhead Dr., Arlington
15. Ruthven, Wyatt, age 4, Steelhead Dr., Arlington
16. Satterlee, Thom, age 64, Steelhead Dr., Arlington
17. Satterlee, Mary, age 61, Steelhead Dr., Arlington
18. Slauson, Lon E., age 59, Steelhead Dr., Arlington
19. Spillers, Billy, age 30, Steelhead Dr., Arlington
20. Spillers, Brooke, age 2, Steelhead Dr., Arlington
21. Webb, Delaney M., age 19, Steelhead Dr., Arlington (alternate address is Marysville)
22. Mangual, Jovan E., age 13, Steelhead Dr., Arlington
The Associated Press contributed to this report