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Energy Fuels Coal Inc. Southfield Mine Semi-Annual Subsidence Monitoring Report (May, 1988 through October, 1988) Subsidence monitoring data for the period of this report were obtained from field surveys conducted in July and October, 1988. Energy Fuels Coal, Inc. (EFCI) has compiled the information in compliance with Colorado Mining and Reclamation Permit Number C- 81-014. Enclosed with this report are survey data pertaining to monitored structures and the high-resolution monitoring grid; and cross sections of the grid. High-Resolution Monument Grid Data collected from surveys of the high-resolution monument grid ("South Grid") are shown on Table 1, Subsidence Monitoring Data Summary. Survey data of total displacement is depicted in cross section form on Figures 1 and 2 representing data from the most recent survey. Only minor additional subsidence was observed for the period of record of this report. Actual subsidence at each subsidence monument is summarized on Table 1. The largest amount of cumula- tive displacement, 2.12 feet, occurred at monument No. 15. As discussed in previous semi-annual reports, monument is influenced by three retreat mined panels and therefore is beyond the scope of subsidence predictions in the permit application. Total sub- sidence at monument No. 4 was measured at 1.20 feet, this being the maximum subsidence detected above the mining panel. This value compares with the maximum expected subsidence of 1.46 feet predicted in the permit application. The measured subsidence change during the period of this report ranged from 0 to 0.04 feet It is anticipated that only minor additional subsidence will occur at the South Grid monuments. The measured angle of draw ranges from 22 to 29 degrees based on Figure 1. The angle of draw is comparable to the range of 20 to 25 degrees predicted in the permit application. City of Florence Water Line Monuments Survey monitoring data for the Florence Water Line Monuments are presented on Table 2, Subsidence Monitoring Data. Measurable subsidence continued to occur only at monument "E", totaling 1.61 feet through the period of record of this report. No measurable subsidence change occurred at monument "E" during the semi-annual period, indicating that subsurface conditions are stabilizing. No,measurable subsidence occurred at the remaining seven water line monuments. It is anticipated that only minor additional subsidence will occur at the water line monuments.