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The one hour lead standard for Utah is 82 µg/1, while the 4 ,day average is 3.~ µg/1. The three river front ground water stations (M9, 10 and 11) all exceeded both limits, while stations M-4, M-5 and M-6 were also high (Figure 17). No other station- - had detectable levels of lead. The source of lead is unknown. Only-one station had high selenium concentrations, station M-14 at 10 µg/1, and the 4 day average limit is 5 µg/1. The 4 day average-limit for zinc is 110 µg/l and the 1 hour average maximum is 120 µg/1. The sample from station M-11 exceeded both limits. The 4 day average limit for cadmium is 1.1 µg/1 and the 1 hour average maximum is 3.9 µg/1. These levels-were-exceeded in the samples from stations M-6, M-9, M-10, and M-11. The 4 day average limit for copper is 12 µg/1 and-the 1 hour `average maximum is 18 µg/l. Only station M-11 exceeded these limits. The maximum allowable concentration of-iron is 1000 µg/1, and-this was exceeded at station-M-10. When collecting .water samples at stations M-9, M-10, and M-1Z all showed iron precipitation in sample shortly after sample. collection. In general, the stations along the Colorado River (M-9, M- 10, and M-11'..all had high-concentrations of one or more metals. The stations located on the eastern side (M-4, M-5 and M-6) also -had high concentrations-of_ one or.more metals. The sources of :these metals is unknown, but most likely .are from groundwater. The surface waters-delivered from Mill Creek are low in metals. One temporary well established northwest of our, station M12 was pumped to collect water for analysis. We noticed that the water effervesced as it came to the surface.- We-used a lighter to test whether the bubbles would ignite, and in fact-the bubbles were of an ignitable gas. Since the gas had the odor of commercial natural gas, we concluded that the substance most likely was not methane, but was gas which escaped from one of the buried .natural gas pipelines that crosses the site. Both field and laboratory water quality data are presented in the Appendix. 30