Pitfalls of Transparency: Lessons Learned from the Milford Flats Fire

摘要

The Community Environmental Monitoring Program (CEMP) consists of a network of 29 radiation and weather monitoring stations located over a 160,000-km2 area of southern Nevada, southwestern Utah, and southeastern California. The program provides stakeholders with a hands-on role in the monitoring for airborne radioactivity that could result from ongoing or past activities on the Nevada Test Site (NTS). The CEMP's mission includes provisions for the transparency of the monitoring data as well as public accessibility to these data. This is accomplished through direct stakeholder participation, public outreach, and near real-time uploads of monitoring data to a publicly accessible web site located at http://cemp.dri.edu/. In early July 2007, a lightning strike ignited a wildfire just outside the city of Milford in southeastern Utah. This fire, named the Milford Flats Fire, grew rapidly and eventually became the largest wildfire in recorded history in the state, burning approximately 567 square miles. At about the same time, the pressurized ion chamber (PIC) located at the CEMP station in Milford began reporting average exposure rates that ranged from four to seven times normal for the area. Initially, it was believed that elevated readings could be a result of gamma-emitting radon progeny released by the fire and transported in smoke plumes. The U.S. Department of Energy issued a press release offering this as a possible first explanation, and the release received a great amount of attention, particularly in the state of Utah, where concerns were expressed that the fire could be causing re-suspension of radionuclides associated with fallout from past nuclear testing at the NTS. Subsequent analyses of particulate air filter samples obtained from the Milford station, as well as an examination of the data reported by the PIC, the timing of the incident, and diagnostic testing on the PIC, showed that the abnormal gamma readings were a result of instrument malfunction.