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Table 3 <br />Radon Emission Estimates <br /> <br /> <br /> <br />hase Total <br />Prorated <br />Area <br />(SIF) Estimated <br />Annual Radon <br />Emissions <br />Ci <br />Current Conditions 14,992 2.70 <br />Phase I 115,557 20.8 <br />Phase Il 211,755 38.2 <br />Phase 111 415,482 74.9 <br />4.3 Estimated Radon Doses <br />Figure 8 shows the locations of the emission points and the flow rate of vented air at <br />various phases in mine development. The figure also shows the location of the nearest <br />resident (i.e. the nearest public receptor). The nearest resident at this time is a part-time <br />resident who occupies a camp trailer on a private parcel approximately 835 meters <br />northwest of the Whirlwind Portal during the warmer months. Currently, the nearest full- <br />time resident is located approximately 3.5 miles (5,600 meters) southwest of the <br />Whirlwind Mine portal. The COMPLY-R program was utilized to estimate the resultant <br />dose to the nearest resident for current conditions and during each mining phase <br />assuming full-time residency. Wind direction and frequency were not input into the <br />program as site-specific wind data is not available. The program conservatively assumes <br />25 percent of wind in each of the 16 compass directions in absence of wind data. <br />The calculated radon dose for each phase of mining is summarized below. The <br />COMPLY-R program output for each phase is presented in Appendix B. <br />4.3.1 Current Conditions Emissions <br />The prorated exposed ore area of the Whirlwind Mine at current conditions is <br />approximately 15,000 square feet giving a total radon-222 emission of 2.70 Ci per year <br />(0.18 Ci/1000 SF x 14,992 SF). This value, along with the following inputs, were entered <br />into the COMPLY-R program. <br />• Release Height - 0 (ground level from portal) <br />Distance from Source to Nearest Receptor - 835 meters (from Whirlwind portal <br />to Zabronsky Parcel residence location) <br />14