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Energy Fuels Coal, Inc. Southfield Mine SEMI-ANNUAL SUBSmENCE MONITORING REPORT (Period: Period May I, 1995 -October 31, 1995) INTRODUCTION The semi-annual subsidence monitoring report compares field survey monitoring data to permit predictions for inventoried structures. Additionally, tabulated survey data is attached showing location and orientation of monuments and structures for the reporting period. Cross-sections are attached that graphically represent survey elevation data at the high-resolution monument grid. DISCUSSION 1. South Subsidence (High-Resolution) Grid The South Subsidence Grid was surveyed on asemi-annually during the 2nd and 4th quarters of 1995. Summarized survey data for the period of this report are shown on Table 1, Semi-Annual Subsidence Monitoring Data Summary. These data are also shown graphically, in cross-section form, on Figures 1 and 2. From the vertical displacement data plotted on Figure 1, the estimated draw angle is depicted. Location of the monument grid and the mine layout are shown on Map 17 in the permit application. Mining activity that could affect these monuments was completed in 1987. Review of the current monitoring data and subsidence predictions show that the displacements of Monuments 13, 14 and 15 exceed the permit prediction of 1.46 feet (maximum expected subsidence). These monuments lie above a mining panel ("B" Panel) that was mined after extraction of "A" Panel, shown on Figure 1. The permit predictions for maximum subsidence contemplate extraction of only "A" Panel. The increased mining width below the monitoring grid, created by extraction of "B" Panel, increases the maximum expected subsidence. The increased subsidence due to mining wider panels is explained in the Rocky Mountain Geotechnical report located in Exhibit 23 of the permit application. The survey data show that little or no movement of the monuments occurred during the reporting period, similar to preceding monitoring periods. It is likely that the strata has consolidated, and little or no additional movement will occur. The estimated angle of draw, shown on Figure 1, is 28.75 degrees. This compares favorably with the 29 degree maximum angle predicted in the permit application. Visual inspections for surface cracking occurred while performing the field surveys. The previously reported surface cracks between Monuments 11 and 12 continue to naturally heal. No new surface cracks were observed.