2013-07-26_REVISION - C1981014 (2)

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Accordingly, Conceptual Model No. 2 is not valid — the seals in the north area of the mine are not restricting flow of water through the mine and the north area of the mine is hydrogeologicly connected. Conceptual Model No. 3 Conceptual Model No.3 assumes that the mine seals in Is' North, l '/z North and 2 North areas do not restrict water flow and allows for localized hydrogeologic connection but, due to the mine layout, these areas are divided from the rest of the mine due to the higher elevations existing along the mine's Main Entries. Accordingly, the north areas refill as a single unit. Conceptual Model No.3 demonstrates that it would take approximately 106 years after the year 2000, or until the year 2106 for the water level to reach the identified monitoring elevation, 5,860.5 feet. The above modeling studies conclude that 1St North, 1 '/2 North and 2 North areas confined by the mine seals are in fact in connection with some portion of the rest of the mine and water is not expected to reach the identified monitoring elevation (5,860.5 ft) of MW -NW for between 106 to 120 years, or between the years 2106 and 2120 respectively. Monitoring wells MW -23 and MW -65 Bishop - Brogden's work demonstrates that monitoring wells MW -23 and MW -65 in the Southfield Mine's groundwater monitoring program are hydrogeologicly connected to the Southfield mine workings. Given the trend of the repressed water levels in the two wells after approximately 15 years after dewatering activities have ceased supports the findings of the slow rate of inflow into the mine which has been expected and observed. Accordingly, the use of MW -23 and MW -65 is adequate to determine the affects of mining activities on the quantity and quality of groundwater in the area especially considering that there is no water expected to be at the MW -NW location to sample for at least 106 years or more. The Bishop - Brogden study concludes, as previously stated, that monitoring of MW -NW or any other well at that location does not provide any additional information regarding the groundwater conditions resulting from previous mining operations. Accordingly, MW -NW could be removed from the monitoring program without affecting the findings of the monitoring program. Hydrogeologic Review Conducted by the DRMS — Mr. Mike Boulay, Hydrologist — June 3, 2013 DRMS conducted an in depth review regarding hydrogeologic conditions at the Southfield mine. An interoffice memorandum from Mr. Mike Boulay, hydrologist for the DRMS, was sent to Mr. Dan Hernandez of the DRMS, dated June 3, 2013. The memorandum consists of the hydrologic review generated by Mr. Boulay which investigates the Southfield mine and surrounding area. A copy of the review is provided in Appendix B of this submittal. Mr. Boulay's hydrologic review supports the findings and conclusions stated in the BBA Summary Report (Appendix A) prepared for EFCI. Mr. Boulay independently concludes that installation of additional monitoring wells down gradient from the mine