The helicopter will fly a grid pattern at an altitude of about 300 feet to collect data. Mapping the normal amounts and location of radioactive material will provide a baseline for comparison to assess contamination if there were a nuclear incident like the events in Fukushima. Sampling in that area of Japan after the nuclear reactors were damaged produced radiation readings, but there was no baseline for comparison so it was unclear how much higher the levels had grown.
The Washington State Department of Health is overseeing the project as the U.S. Department of Energy’s Remote Sensing Laboratory Aerial Measurement System conducts the flyover. The project has been in planning since 2009 and is funded by a grant from the U.S. Department of Homeland Security.
The data collected will be part of a report after quality assurance review. The report will be available to the public, though some information may be withheld for national security reasons. If levels of radioactivity are high enough to pose any health concern, the source will be investigated.
The flyovers will start in Seattle and Bellevue before moving to other areas of King and Pierce Counties, including Tacoma. During the Puget Sound flyovers, the helicopter will be based at Boeing Air Field and will make daily flights between July 11 and 28.