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 dangerous stew of toxic contaminants.
Authorities in Washington state believe 22 people are still missing in the deadly mudslide that has killed at least 24 people.
That's down from the 30 people they previously considered missing.
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 on March 22 and left dozens of people dead or missing, authorities said.
The official death toll rhas continued to rise after a rain-soaked hillside collapsed above the north fork of the Stillaguamish River, northeast of Seattle.
The dead included a 4-month-old infant and two older children, ages 5 and 6.
Authorities said the number of people still listed as missing had been cut to 22 from 30.
It was not immediately clear if that number was lowered through the identification of bodies. Of the 24 dead, 18 have been identified by medical examiners.
Meanwhile, 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.
‘‘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 Stillaguamish 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.
STILL SEARCHING FOR BODIES
The Snohomish County medical examiner's office said it has positively identified 18 of the 24 victims in the official death toll.
Snohomish County Executive Director Gary Haakenson said the remains of three additional victims were found on Monday (local time), but they have not yet been included in the medical examiner's official numbers.
Steve Harris, a division supervisor for the search effort, said search teams are learning more about the force of the March 22 slide, and that was helping them better locate victims in a debris field that is 21 metres deep in places.
"There's a tremendous amount of force and energy behind this," Harris said of the slide. He didn't provide further details.
Harris said search dogs were the primary tool for finding remains in the small, mountainside community about 88km northeast of Seattle. He said searchers were finding human remains four to six times per day. Sometimes crews only find partial remains, which made the identification process harder.
A makeshift road completed over the weekend links one side of the 122-hectare debris field to the other.
Governor Jay Inslee on Monday asked President Barack Obama for a major disaster declaration in Snohomish County to make programmes available to help individuals, households and businesses.
Last week, a federal emergency declaration was approved that provided a federal disaster team and specialised personnel to the slide area.
Estimated financial losses have reached US$10 million (NZ$11.52m), Inslee said, adding that about 30 families need assistance with housing, along with personal and household goods. The estimated losses include nearly US$7 million in structures and more than US$3 million in their contents, Inslee's letter said.
Members of the Seattle Seahawks football team and Seattle Sounders soccer team were scheduled to visit with community members on Monday evening.