Recovery teams struggling through thick mud up to their armpits and heavy downpours at the site of the devastating landslide in Washington state are facing yet another challenge - an unseen and potentially 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 small, rural community and left dozens dead and missing northeast of Seattle on the morning of March 22.
The official death toll stood at 21 on Monday, with 30 people still listed as unaccounted for nine days after a rain-soaked hillside collapsed above the north fork of the Stillaguamish River.
County officials planned to present their next update on the status of the recovery operations at 11 a.m. local time on Monday.
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 and across state Highway 530, flattening dozens of homes on the outskirts of the town of Oso in the foothills of the Cascade Mountains.
Jason Biermann, program manager for the Snohomish County Emergency Management Department, said late on Sunday that the official loss of life so far included 15 victims whose remains have been identified by medical examiners and six more still awaiting positive identification.
He said four additional sets of remains were found on Sunday that for reasons not explained to reporters were being left out of the official tally of dead.
NO SIGNS OF LIFE
Authorities have offered conflicting casualty figures, and the process of accounting for the number of dead has likely been complicated by the condition of some bodies that rescue workers have said are not always found intact.
They have in recent days reported locating a number of bodies that have not been included in the official death toll, previous to the four reported on Sunday, but have not provided further updates on the status of those remains.
No one has been pulled out alive and no signs of life have been detected since the day the landslide hit, when 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 mound of muck and debris, which county authorities say covers 1 square mile (2.6 sq km).
Scores of recovery workers, including National Guard troops just back from Afghanistan, picked through the swampy, rubble-strewn mud on Sunday as overcast but dry weather provided a welcome respite from heavy rains of recent days.
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 (5 to 23 meters) 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, said relatives had not given up all hope of finding a "miracle" survivor, and neither had authorities.
"We're looking for that miracle right now," the governor said during a stop at an airfield in the neighboring town of Arlington. "If we don't find that miracle, they're also looking for the knowledge of the fate of their loved ones."