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o r',j ~ OJ CHAP TER V VERIFICATION PROGRAM A verification program was initiated in 1980 to investigate the flow-mechanism hypothesis described in the previous chapter. The pro- gram included the installation of a monitoring network and the cleaning, testing, and plugging of three of the abandoned oil wells. When specific sites and activities had been outlined, studies were conducted to assess the impact that the verification program would have on the natural environment and on cultural resources. These studies showed that no significant impacts to the environment would occur as a result of the verification program. The program, therefore, was granted a Categorial Exclusion by the Commissioner of Reclamation, rendering preparation of an environmental assessment unnecessary. Monitoring Network Prior to well reentry activities, a monitoring network was in- stalled to establish a water quality base and assess conditions after verification activities were completed. Eight monitoring stations were built at springs or seeps and six observation wells were installed. To establish a water quality base, water levels, flows, and temperature were measured and water samples were taken for analysis of electrical conductivity, major anions and cations, and TDS. When stabilized from the disruption of station construction, the flows of springs and seeps remained relatively constant aside from seasonal effects due primarily to surface runoff from melting snow and rain, high spring flows in the White River, and evapotranspiration. c Three of the six observation wells are located on top of the dome near the Scott and Marland Wells and three on the south face nearer the river. A cross section of the Meeker Dome area and the location of observation wells are shown on Figure 3. Depths of the wells on top of the dome ranged from 190 to 280 feet, and water was not encountered until the wells had penetrated approximately 100 feet into the Morrison Formation. The water was under artesian pressure, although it was not sufficient to flow at the surface. Laboratory analyses showed that the water quality in all three wells was essentially the same, indicating the water is probably from the same source. The three observation wells nearer the river are relatively shallow. One near the Meeker Well is 30 feet deep, one east of Meeker Well is 80 feet deep, and one south of State Highway 132 is 85 feet deep. The first two wells were drilled into the Morrison Formation and were under sufficient pressure to flow at the surface. The third well bottomed in the Dakota Sandstone or possibly the very uppermost levels of the Morri- son Formation and, although under artesian pressure, it did not flow. 15