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Wells depicted in blue are located inside the mining panel. Wells in orange represent up-gradient <br />monitoring points and wells in yellow are outside the panel and down-gradient. All of the drilled <br />and proposed solution-mining production wells are located inside, the border representing the 0-5 <br />year mining panel. <br />Ground water monitoring began in September 1999 and continued on a monthly basis for 15 <br />months to provide baseline data that would characterize the aquifers prior to commercial mining <br />activity. The monitoring program continued on a monthly basis following the initialization of the <br />first injection into the wells in October 2000 and to date includes over 15 operational quarters of <br />data from each sampling location. <br />American Soda uses a network of 25 monitoring well completions (as detailed in Table 1 and <br />shown in Figure 1 and 2) to monitor ground water quality and water levels at the Piceance Site <br />for the 0-5 year mining panel. The Upper Aquifer is monitored at 11 locations, the Lower <br />Aquifer is monitored at l O locations, and the Alluvial Aquifer is monitored at 4 locations. Of the <br />25 well completions, 15 completions (10 well bores) are located outside the 0-5 year mining <br />panel, and 10 completions (8 well bores) are located within the 0-5 year mining panel. <br />The four alluvial monitoring wells include well 19-3, well 21-2, we1121-5, and we1128-1. Three <br />of the four alluvial monitoring wells are used to monitor the water level and water quality of the <br />Alluvial Aquifer adjacent to Piceance Creek. The fourth alluvial monitoring well is located <br />down gradient of the proposed location of the Piceance creek evaporation pond. It was intended <br />to monitor potential leakage from the pond. The evaporation pond has never been constructed <br />and monitoring of well 19-3 has never shown sufficient water to collect a sample. The period of <br />record for this well shows a constant water elevation at the bottom of the well. Well 19-3 is <br />likely to remain a dry well unless the evaporation pond is constructed and fluids are placed in the <br />pond. Consequently, well 19-3 will be checked quarterly to verify that no water is present, but it <br />is not considered further in this monitoring plan. If the pond is constructed, fluids are stored in <br />the pond, and a sample can be obtained, then monitoring of well 19-3 will resume on the same <br />frequency and for the same parameters as the other alluvial monitoring wells. <br />There are three multiple-completion monitoring wells (21-3, 21-4, 29-4), which were installed in <br />1999. These multiple-completion monitoring wells provide nested or co-located monitoring <br />locations for the alluvium, Uinta Formation, A-Groove, B-Groove, and Dissolution Surface. The <br />multiple-completion monitoring wells were constructed in large-diameter boreholes to allow a <br />grout mixture to flow freely and fully seal the borehole between the completion zones. All well <br />construction materials (sand, bentonite, and grout) were placed in the bottom of the borehole by <br />the tremmie method. Each completion is constructed of 2-inch-diameter, PVC or fiberglass well <br />casing and well screen. We1121-3 is located down-gradient of the first-phase mine panel and has <br />four nested completion zones (Uinta, A Groove, B Groove, and Dissolution). It is the point of <br />compliance well as defined by the Colorado Division of Minerals and Geology. Another well, <br />designated as we1129-4, is located up-gradient. of the first-phase mine panel, and has three nested <br />completion zones (Uinta, A Groove, and Dissolution Surface). A separate B-Groove completion <br />is located adjacent to the 29-4 nest (29-4B). The third multiple completion monitoring well, <br />FINAL: Modification No. 9, UIC Area Permit No. C030858-00000 <br />Page 27 of 46 <br />