2015-03-12_PERMIT FILE - C1981014A (2)

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• Freshwater Pond No. 3 (reclaimed) • Sedimentation Pond No. 4 • Mine Substation (scheduled for removal) • Powerlines (most removed during reclamation) • City of Florence Waterline (portions removed while mine was in operation) • Telephone Communications Fines (most removed during reclamation) • Thompson Well *, in Sec. 25. T20S. R70W • Corley Company Well *, Permit No.119459, in NE4,' SE4, Sec.24, T20S, R70W • Corley Company Well *, Permit No.75659, in SW4, NW4, Sec. 19, T20S, R69W • Corley Mine Shop Building *, in Sec. 24. T20S. R70W *Structures added in response to Permit Renewal No. 06 (RN -06) Structures associated with EFCI's mining and related activities, including office, shop, warehouse, preparation plant, and loadout facilities, were not undermined, and therefore, were not affected by subsidence. The configuration of potentially affected structures within the area of concern is illustrated by the Mine Surface Facilities Map. (Map 18). EFCI's subsidence inventory does not delineate any renewable resource lands within potentially affected areas. Probable and Worst Case Subsidence; Based on the subsidence report prepared by RMG in 1983 for Dorchester, both the maximum expected probable and worst -case subsidence ranges were predicted. RMG predicted probable maximum vertical subsidence for combined advance and retreat mining to range from 146 to 5.85 feet. These predictions apply to Southfield's overall mine plan within the permit area. Where pillars are left (development extraction only). RMG predicted worst -case vertical subsidence ranging from 2.60 to 4.36 feet. The RMG subsidence predictions and subsidence control plan were used by EFCI during the period of active mining and have proven to be accurate. Actual subsidence monitoring data collected over the past eighteen years by both Dorchester and EFCI indicate vertical subsidence ranging between 0.03 and 3.2 1 feet (Florence Waterline Station I), well within the ranges predicted by RMG. Actual subsidence data can be found on Table 1, High Resolution Grid Survey Data, and in the Semi- Annual Subsidence Reports contained in Exhibit 23, Subsidence Information. 2.05.6 -56 Revised: 9/2014 RN -06