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III IIIIIIIIIIIII III Energy Fuels Coal, Inc. Southfield Mine SEMI-ANNUAL SUBSIDENCE MONTI'ORING REPORT Period: January 1 -June 30, 2001 Introduction The semi-annual subsidence monitoring report compares field survey monitoring data to permit predictions for inventoried swctures. Summarized survey data aze shown in attached Table 1, Semi-Annual Subsidence Monitoring Data. These data show location and orientation of monuments and swctures 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 aze conducted quarterly on the swcture monuments shown on Table 1. EFCI will survey the South Grid monument network after mining operations have permanently ceased, as approved in the permit. EFCT performed two quarterly subsidence surveys of the swctures 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. Discussion 1. swctures 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 swctures aze 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 swctures follows below. 1. l Thompson Ranch Structures Survey data for the reporting period indicate vertical changes, compared to original data, ranging from -0.25 to -0.32 feet. These values were obtained during the 2nd quarter survey. During this survey there was a 0.2 to 0.3 foot 'variation' in the elevation data believed to be from GPS survey technique. No subsidence is expected since mining has not occurred below the ranch area that would cause measurable subsidence. In addition, there are no physical indications of subsidence on or near the monitored swctures.