2009-02-02_REPORT - C1981008 (15)

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Topsoil and spoil samples are shipped to Servi-Tech Laboratories in Hastings, NE for analysis. The analytical results (see Attachment 2008-A) indicate that all samples are suitable. A soil study was conducted in the NI-12 boundary; west of 27 road on the subsoil, due to an elevated lab parameter (Electrical Conductivity or EC) that exceeded the 4.00 mmho/cm limit. This study is contained in Exhibit 2008-B in its entirety as well as results from a follow up soil study. This investigation is currently on going. No additional grading, special handling, or amendment application took place in 2008. Soil Redistribution In general, the topsoil that was used for redistribution is live handled from ahead of the active mining area to the awaiting backfill area. Because the material is moved by mine equipment and is scheduled amongst the other mining functions. Currently only the area south of BB road and west of 27 road (Morgans) is handled in a different manner. This area has 2 different zones that vary in thickness; A (top) & B (lower) and is considered to be mostly prime farmland. These zones are striped and segregated into different stockpiles. These zones will be laid down in the same zone they were striped from; B underlying A. Occasionally, mining parameters require that some topsoil be stockpiled adjacent to a laydown area prior to spreading. Topsoil Thickness The thickness of soil replaced during 2008 was verified by survey at an approximate 18 inch depth. Sample sites for the New Horizon 2 mining area were selected systematically utilizing a 465 foot by 465 foot grid pattern. Sites at New Horizon 2 were determined from CAD drawings using distances and azimuths from established survey points and located in the field by a survey grade GPS unit. A 2-3/4 inch hand auger was used at each site to excavate a pilot hole through the entire soil strata. An abrupt boundary, defined by color and rock fragment content, typically occurred at the soil/spoil interface. The replaced soil thickness was measured through the pilot hole immediately after encountering the spoil. Minor Revision # 44 was approved by DMG in August 2000. The revision, based on years of extensive sample analysis, allowed for a reduction in the parameters for which the soil is analyzed. Soil thickness as determined by past sampling is shown on Exhibit 2008-6. Soil thickness information for each sample site is located on the map. The average topsoil thickness for the 2008 sampling session is approximately 1.8 feet. The New Horizon 2 has a minimum requirement of"... approximately 1.0 foot for topsoil laydown thickness." (2.05.4(2)(d)-13). . New Horizon 2 has many different soil thickness requirements as shown on Map 2.05.4-4 in section 2.05(2)(d) of the current Permit C-81-008. Exhibit 2008-8 shows the type and area of the reclaimed land. Topsoil Salvage and Storage All suitable soil has been salvaged ahead of mining at New Horizon 2. Approximately 10,390 cubic yards (Pre 1995 LIFT 1), 41,360 cubic yards (Pre 1995 LIFT 2), 22,900 cubic yards (Pre 1995 MIXED) and 32,233 cubic yards (2008 Topsoil), a total of 106,883 cubic yards of soil are stored in all stockpiles at the end of 2008 (non Morgan soil). The total of Morgan Lift A, Lift B, and Mixed is 209,099 cubic yards. A total of 173,110 cubic yards will be needed to replace 2008 (non Morgan) disturbance leaving 4,868 cubic yards excess. The total topsoil (w/Morgan soil) balance EOY 2008; 213,967 cubic yards excess. Exhibit F:\Eng\DATA\Word\Ann Reclaim Report\2008\2008RECRPT.doc