The Tracy Power Plant is situated 27 km east of Reno. Nevada, in a region of complex terrain. The power plant is in a valley surrounded by peaks rising to around 950 m above the power plant elevation. During 1984. the United States Environmental Protection Agency carried out a series of 14 experiments between August 6th and 27th. for a total of 128 hours of data collection, mainly during the late evening and early morning hours .
The power plant was maintained in warm stand-by status as a tracer gas (SF6) was released from the 91-in stack on the power plant, and concentrations were measured at 110 receptors (Figure 1). The majority of the receptors were positioned on high areas of the terrain, and around 20 were located within the valley. Different combinations of receptors were used for each of the experiments.
Meteorological data were measured at an instrumented 150-m tower located 1.2 km east of the plant. Wind speed, temperature and vertical turbulence parameter data were profile obtained from . The observed data available included hourly average concentrations of SF6 at each receptor point and meteorological data for each hour of each experiment.