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 Image Number K7124-1 |
Atop the roof of a high school in Kennewick, Washington, meteorologist Mary Hattendorf changes a 10-micron filter on a high-volume dust sampler. Dave Lauer (wearing cap), Clean Air Authority director in Benton County, Washington, and meteorological technician John St. Clair inspect the filters on another dust sampler.
Photo by Jack Dykinga
