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-5- Alluvium In the Yampa River alluvium there are two monitoring wells, YAW-3 and YAW-5 that are sampled quarterly for full suite parameters and monthly for field parameters. In reference to Figure 21 conductivity levels have been extremely high throughout 1984, (8000-12000 umhos/cm). In fact conductivity levels have been high throughout the life of monitoring well YAW-5. These high levels may be due to either improper or faulty well construction or they are natural in-situ background conductivity levels. The water is chemically a NaSO4 type water. Minor and trace elements are within acceptable limits. Three monitoring wells completed in the Williams Fork alluvium, AVF-3, AVF-5, and AYF-6 are sampled on a quarterly basis for full suite parameters and on a monthly basis for field parameters. Except fora brief period from January, 1984 thru May, 1984 conductivity levels remained at an acceptable level. During this time conductivity levels in Well AVF-5 averaged over 3,000 umhos/cm. Throughout the remainder of the year conductivity levels were under 2000 umhos/cm. Chemically, the water is a NaHC03 type. Minor and trace elements are within acceptable limits. Springs Empire Energy monitors four springs for water quality. North, Haxton and Lippard No. 2 Springs are sampled quarterly for full suite parameters and sampled monthly for field parameters. No. 1 Strip Pit is sampled bimonthly for NPDES parameters and weekly for field parameters. Summaries of 1984 full suite analysis and cumulative water quality analysis are presented in Tables 31-35. These data indicate there are no water quality problems in any of these springs. Surface Water Flow measurements are made at four surface water monitoring sites. Two sites are on the Yampa River, YS-1 and YS-2, and are measured weekly. Two sites re on the Williams Fork River WF-1 and WF-2. WF-1 is measured weekly and WF-2 is measured on a continuous basis. Discharge hydrographs, Figures 23 and 25, for the Williams Fork River indicates peak discharge occurs during May through July. As predicted electrical conductivities decrease significantly during this period of high flow. Water quality improves due to dilution from snowmelt. Figure 26 shows a dramatic increase in suspended solids during high flow. This is a normal predicted phenomenon. No degradation to water quality in the Yampa and Williams Fork Rivers have occurred as a result of Empire Energy's mining operation. In addition no measurable impact to flows in the Yampa and Williams Fork Rivers have resulted from Empire's mining activity. r .l