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Energy Fuels Coal, Inc. Southfield Mine SEMI-ANNUAL SUBSIDENCE MONITORING REPORT (Period: July 1, 1996 -December 31, 1996) IN'T'RODUCTION The semi-annual subsidence monitoring report compazes field survey monitoring data to permit predictions for inventoried structures. Summarized survey data aze shown in attached Table 1, Semi-Annual Subsidence Monitoring Data. These data show location and orientation of monuments and structures for the reporting period. Additionally, original survey data for all subsidence monitoring locations aze shown on attached Table 2, Original Subsidence Monument Data. EFCI performed two quarterly surveys of the subsidence monuments and structures shown on Table 1 during the reporting period. The survey conducted during the forth quarter of 1996 utilized GPS equipment to determine both the vertical and horizontal location of all the stations. This is the first time that this type of equipment has been utilized. Discussion of the data obtained with the GPS equipment is shown below. During the forth quarter of 1996 survey, the single Newlin Creek Point station was reestablished neaz the original station to facilitate access for future surveys. Further discussion of this change follows below. DISCUSSION 1. Structures Structures monitored quarterly for subsidence include the Thompson Ranch buildings, the Florence City water line, and the Newlin Creek point. Summarized survey data for these structures are shown on accompanying Table 1, Semi-Annual Subsidence Monitoring Data Summary. Location of the structures and monuments with respect to the Mine layout are shown on Map 17 in the permit application. Discussion of survey monitoring data compared to permit predictions for inventoried structures follows below. 1.1 Thompson Ranch Swctures Survey data for the final quarter of the reporting period indicate that subsidence in the range of O.12 to 0.14 feet has occurred. This range of vertical movement exceeds any previous monitoring data. Since no retreat mining operations occurred in the area of these structures, EFCI believes that there is a small inherent vertical error in the GPS generated data. Verification of the possible error will be determined from subsequent quarterly surveys. 1.2 Newlin Creek Point Survey data for the Newlin Creek point show no additional subsidence through the third quarter of 1996 survey. These data agree with preceding monitoring periods. No mining operations have occurred in the vicinity of this survey point since 1982 to cause additional subsidence.