( CNN ) -- The official death toll in last month 's massive landslide in rural Washington state rose to 29 , up one from the previous day , Snohomish County medical examiner 's office representative Kelly Stowe said Wednesday . About 15 people remain missing , authorities have said . A rain-saturated hillside along the north fork of the Stillaguamish River gave way on March 22 , sending a square-mile rush of wet earth and rock into the outskirts of the town of Oso in the North Cascade Mountains . The landslide left behind a graveyard in the debris , where bodies have been recovered and crews painstakingly search for people who are listed as missing . Rescuers have been trudging through the muck , which is 70 feet thick in some places . Hundreds of people and cadaver dogs are involved in the search , officials have said . Larry Nickey , one of the incident commanders , told reporters Wednesday that he is increasingly using professional teams with extensive training in searching for human remains , and is scaling back the number of volunteers in the field . Nickey said searchers are focusing on areas of the grid where they feel there is a high probability of finding bodies . He said that one body found Wednesday is not yet counted in the official toll . The search is perilous . The debris field is full of toxic sludge -- a combination of human waste , toxic chemicals from households , propane tanks , oil and gas , according to Lt. Richard Burke of the Bellevue Fire Department . Every person , animal and thing that comes out of the field has to be decontaminated . Some of the workers have come down with dysentery , and supervisors are concerned that others may be at risk for tetanus . The weather has been good for the past three days , allowing water to recede from the debris field , but the forecast looks bad , especially for Friday , when the National Weather Service says there is a 100 % chance of rain , which will be heavy in spurts . According to CNN affiliate KOMO , a bank with branches in Arlington and Darrington said it would forgive any home loans and car loans that were n't covered by insurance . `` Coastal Community Bank is ready to stand behind our customers , and if they are not insured and they owe us that debt , we will forgive that debt , '' CEO Eric Sprink told KOMO . The station reported that of the dozens of primary residences destroyed , none had landslide insurance . Gov . Jay Inslee has asked the federal government for assistance , including disaster grants . As searches continued , a major state university said it was ready to help its students from the area . Washington State University will waive tuition for the next academic year for students directly affected by the slide , specifically students with permanent addresses in Oso or nearby Darrington , university spokeswoman Kathryn Barnard said Wednesday . The number of students this could affect was n't immediately clear . Darrington has about 450 students enrolled in its school system . CNN 's Ana Cabrera contributed to this report .
NEW : About 15 people are still missing . Bank to forgive uninsured homes , cars that were lost in the landslide . A mile-wide landslide devastated an area in rural Washington state on March 22 . Hundreds of people are involved in search efforts .