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Energy Fuels Coal, Inc. Southfield Mine SEMI-ANNUAL SUBSIDENCE MONTI'ORING REPORT Period: July 1 through December 31, 2001 Introduction The semi-annual subsidence monitoring report compares field survey monitoring data to permit predictions for inventoried structures. Summarized survey data are 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, the original survey data and current quarterly survey data for all subsidence monitoring locations are shown on attached Table 2, Current Report Data. Field surveys are conducted quarterly on the structure monuments shown on Table I. EFCI will conduct a survey the South Grid monument network prior to bond release for the area containing the monuments, as approved in the permit. EFCI performed two quarterly subsidence surveys of the structures shown on Table 1 during the reporting period. The surveys were conducted using differential GPS equipment for both horizontal and vertical control. Discussion of the subsidence data, and any current visual observation information, is shown below. 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 Structures Survey data for the reporting period indicate vertical changes, compared to original data, ranging from -0.OS to -0.09 feet. These data are consistent with values obtained during previous monitoring periods which show insignificant subsidence has occurred in this area. No subsidence is expected since mining has not occurred below the ranch azea that would cause measurable subsidence. In addition, there are no physical indications of subsidence on or neaz the monitored structures.