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Mr. George V. Patterson, General Manager Energy Fuels Coal, Inc. P.O. Box 459 Florence, CO 81226 December 12, 2013 Subject: Review of Mine Related Subsidence Potential at Corley Mine Shop Building, a.k.a. Corley Concrete Block Barn Dear George, The following report includes a discussion and engineering evaluation concerning subsidence associated with historic Southfield Mine operations specifically occurring in the vicinity of the Corley Mine Shop Building ("Shop Building "). At the request of George Patterson, Energy Fuels Coal, Inc. ( "EFCI "), I have utilized mine maps, mine permit documents, and survey data to interpret the potential extents of subsidence relative to the location of the Shop Building. The Shop Building is located in section 24, R70W, T20S, on lands owned by the Corley Ranch Company. This building is a concrete block structure that was primarily utilized in conjunction with former mining operations in the Rex Carbon coal seam, and was constructed prior to the 1979 start-up of the Southfield Mine. EFCI subsequently conducted room and pillar mining operations in the area south of the Shop Building during the 1990's. During active mining operations, EFCI was not required to conduct a pre - subsidence survey or perform periodic subsidence monitoring of the structure because proposed mining projections indicated no potential for subsidence at the Shop Building location. Data and documents utilized in this report include the certified Southfield Mine Permanent Closure Map ( "Mine Closure Map "), Sheet 1 of 2, Dated 09 -18 -2001; Section 2.05.6, Subsidence Survey, of approved Colorado mining permit No. C -14 -1981; and survey coordinates obtained on 10 -21 -13 of the Shop Building by W D Corley ( "Corley ") and certified by John H. Keillers, PLS, then delivered to EFCI. A review of the Mine Closure Map, Sheet 1, indicated that underground mining operations in the Red Arrow seam occurred near the Shop Building in a section of the mine including 2 North Submains and Panel `B East'. No other mining by EFCI occurred in the vicinity of the building. Using the survey coordinates provided by Corley, the Shop Building location was computer plotted on the relevant portion of the Mine Closure Map as shown on attached Figure 1. In order to portray subsidence limits, a cross - section representing this area of the mine and overlying surface along with the Shrp Building was developed from Figure 1, and is shown on attached Figure 2. The elevation shown for the Shop Building is an average of the four elevations provided for the structure. The angle of draw (29 degrees), which is the maximum angle of draw according to the approved mining permit, was then plotted based on the extent and elevation of the mine workings. Figure 2 shows the surface intercept location of the projected draw angle relative to the Shop Building. A distance of approximately 210' is shown between the Shop Building and projected extent of any potential surface subsidence. The projected subsidence limit is portrayed on Figure 1 and Figure 2.