DARRINGTON, Washington (Reuters) - Recovery teams struggling through thick mud up to their armpits and heavy downpours at the site of a devastating landslide in Washington state are facing yet another challenge - an unseen and potentially more dangerous stew of toxic contaminants.
Sewage, propane, household solvents and other chemicals lie beneath the surface of the gray mud and rubble that engulfed hundreds of acres of a rural community after the mudslide that left dozens of people dead or missing northeast of Seattle on the morning of March 22, authorities said.
The official death toll was raised to 24 on Monday - up from 21 a day earlier - with 30 people still listed as unaccounted for nine days after a rain-soaked hillside collapsed above the north fork of the Stillaguamish River.
Managers of the recovery operation were taking special measures to protect the hundreds of workers on the scene from chemical exposure and to prevent toxic sludge from being carried offsite.
"We're worried about dysentery, we're worried about tetanus, we're worried about contamination," local fire Lieutenant Richard Burke, a spokesman for the operation, told reporters visiting the disaster site on Sunday. "The last thing we want to do is take any of these contaminants out of here and take them into town, back to our families."
The torrent of mud released by the slide roared over both stream banks of the river and across state Highway 530, flattening dozens of homes on the outskirts of the town of Oso in the foothills of the Cascade Mountains.
The county medical examiner's office said on Monday it had received a total of 24 victims from the slide, with 17 positively identified. The dead included a 4-month-old infant and two older children, ages 5 and 6.
That number was up from an official toll of 21 victims announced late on Sunday, when officials said they had also located four additional sets of remains that were omitted from the official tally without explanation.
The death toll in the disaster has been somewhat of a moving target in recent days as county officials have reported locating a number of bodies without adding them to their fatality toll.
Search crews, with the help of dogs, have been regularly finding and retrieving more remains, at least four to six times a day on the eastern half of the massive debris pile, recovery team supervisor Steve Harris told a news conference.
Authorities have said the process of accounting for the number of dead has been complicated by the fact that the bodies are not always found intact.
Harris said the mudslide struck with such force that whole cars were "compacted down to about the size of a refrigerator, just smashed to the point where you can hardly tell it was a vehicle."
No one has been pulled out alive and no signs of life have been detected in the disaster zone in the nine days since the slide hit. At least eight people were injured but survived.
Officials have conceded it may be impossible to account for everyone lost in the disaster, and that some victims might end up being permanently entombed under the giant mound of muck and debris. The county has said the slide covered about 1 square mile, but maps of the site appear to show a debris field that extends over an area about half that size.
Scores of recovery workers, including National Guard troops just back from Afghanistan, picked through the swampy, rubble-strewn mud on Monday under fair skies that provided a welcome respite from heavy rains of last week.
Weather forecasts for the week ahead showed a continued drying trend, "which will help crews and reduce the risk of flooding and additional slides," the county said in a statement.
Some parts of the slide area, buried beneath 15 to 75 feet of mud, twisted tree trunks and wreckage, were still too dangerous to enter, Burke told reporters.
Like most workers at the site, Burke's boots were sealed to his trousers with duct tape, a precaution to keep toxic sludge out of his clothing. National Guard troops also set up a decontamination station where workers scrubbed themselves with soap and hot water before leaving the site.
"This is going to be a hazardous materials site for many years while we try to get this cleaned up," Burke said.
Governor Jay Inslee, who toured the disaster zone by helicopter on Sunday, asked President Barack Obama on Monday for a major disaster declaration that would make a federal programs available to assist individuals, households and businesses affected by the slide.
The request followed the approval of a federal emergency declaration last week that paved the way for the U.S. government to send in its own disaster team and specialized personnel.
In a bid to boost gloomy spirits in the community, members of two of Seattle's professional sports teams, the Seahawks of the National Football League and the Sounders Major League Soccer team planned to visit the area later on Monday.