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Energy Fuels Coal, Inc. Southfield Mine SEMI-ANNUAL SUBSIDENCE MONITORING REPORT (Period: Period November I, 1995 -June 30, 1996 ) IN'T'RODUCTION The semi-annual subsidence monitoring report compares field survey monitoring data to permit predictions for inventoried structures. Tabulated survey data are shown in attached Table 1, Semi-Annual Subsidence Monitoring Data, showing location and orientation of monuments and structures for the reporting period. Additionally, original survey data for all subsidence monitoring locations are shown on attached Table 2, Original Subsidence Monument Data. Southfield's subsidence monitoring and reporting procedures changed during the period of this report according to approved Technical Revision No. 24. These changes include elimination of monitoring/ reporting of the high-resolution grid, and modifying the monitoring and reporting schedule to coincide with calendar quarters. In accordance with the approved revision, this report picks-up from the end of previous reporting period and so includes the last two months of 1995 and the 1st and 2nd quarters of 1996. 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 Structures Consistent with previous subsidence surveys, survey data for the reporting period indicate that no subsidence is oceumng. No retreat mining operations occurred in the area of these structures. 1.2 Newlin Creek Point Survey data for the Newlin Creek point show no additional subsidence during the reporting period. These data agree with preceding monitoring periods. No mining operations have occurred in the vicinity of this survey point since 1982. 1.3 Florence Water Line Survey data obtained at the eight monuments along the Florence Water Line indicate minor subsidence occurring only at Monuments F and G during the reporting period. The amount of measured subsidence at these monuments ranged from 0.26 to 0.69 feet. The maximum measured subsidence along the water line has occurred at Monument I, totalling 3.05 feet since the original survey. This value is within the permit maximum expected and worst~ase expected subsidence values of 2.79 and 4.36 feet respectively.