2011-07-13_REPORT - C1981008 (9)

Home Browse Search

Topsoil Thickness The thickness of topsoil replaced during 2010 was located north of BB Road and verified by the soil survey to approximate 1.9 feet (23 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 backhoe excavated 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 on the cut bank. PR -06 received approval in late 2010; thus changing various topsoil and subsoil sampling requirements and can be viewed in PR -06, 2.05.4(2)(d). Soil thickness as determined by past sampling is shown on Exhibit 2010 -6. New Horizon 2 has several different soil thickness requirements and is noted on Map 2.05.4 -4 in section 2.05(2)(d) of the current Permit C -81 -008 and is noted on Exhibit 2010 -6. Topsoil Salvage and Storage All suitable soil has been salvaged ahead of mining at New Horizon 2. The approximate volumes for all stored top soil are expressed in cubic yards. Topsoil Type Stockpiled Required Balance • Pre 1995 LIFT 1 10,590 200 10,390 • Pre 1995 LIFT 2 41,760 400 41,360 • Pre 1995 MIXED 66,025 43,125 22,592 • Mixed -Zone 7 45,317 69,072 - 23,755 • Mixed -Zone 8 14,730 14,730 0 • Area 4 Mixed 5,780 5,780 0 Non - Morgan topsoil stockpiled totals 50,587 • Morgan Lift A 185,128 108,592 76,536 • Morgan Lift B 345,868 289,869 55,999 • Morgan Mixed 132,271 131,238 1,033 Morgan topsoil stockpiled totals 154,403 Exhibit 2010 -10 gives details on locations, types, volumes, and stockpile identification. The soils were stockpiled separately by soil types and property ownership as specified by our permit. Cover Crop All topsoil stockpiles in the prime farmland area were hydro- seeded with the approved temporary seed mix #3. During this application, organic based mulch and tacktifier were applied to aid in dust and erosion control as well as providing a seed bed for better germination. Ponds 009, 011, 012, and, 013 were broadcast seeded with mix #3 as was their associated ditches. The OB1 stockpile near Pond 012 was broadcast seeded with mix #3, as was a section of Mt. Nucla that was disturbed during reclamation activities. Several other areas were seeded to the temporary mix due to the late approval of PR -6. F: \Eng \DATA \PROJECTS \2011 \ANNUAL RECLAMATION REVIEW RESPONSE 2008 & 3 2010 \2010RECRPT 2011RESPONSE.doc