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1--------- - - - - -- -- 1 I I ' - � r/ 1 ' 46 )7 II _ 4624 , l- l 1 Ij { a627�1 to I F 1 1 1 I E 1 i 1 \ 1 p 1 - � 1 - -- I 1 '4 RESERVE OVERBURDEN SUPPLY 1 EXCAVATE ONLY IF NECESSARY FOR FILL. 1 . .6 (SEE RECLAMATION PLAN - EXHIBIT E) 1 lO .4614.6 1 I 6. 1 �a620 Ir II ,4614.5 612.2 n1 � 1 A611.2 - I 4611.3 .46119 11 .4609.5 jl ,4609.5 ,46092 MINING AREA I 46,.. 1116'H t_�_ I -- _Tae_e- - - -±-- _-4eoe all 1 7 I � - I 1 610.a \ 1 NCI' ,4610.2 ".. e� DRAINAGE OUTLET 1 � �.�"� .. ....460• 1 , 46 '. a 7 .46072 Phase 2 LNG 3 /l'• \�t'G .0 �. . �I 4605.5 I� I NOTES ON MINING OF PHASE 2 1. Install groundwater barrier wall and streambank stabilization structures in weak areas along river bank. Streambank stabilization structures should be small jetties projecting into the river and keyed into bank. 2. First mining to occur in Mining Area 1. Final slope of south wall (next to groundwater barrier wall) must be no steeper than 3:1. Other pit walls may be steeper if desired. This first area will provide a location for dewatering of the rest of Phase 2. It will eventually be backfilled with a blend of overburden and waste concrete to provide drainage from 25th Lane. Do not mine closer than 200' from nearby buildings. 3. Mining in the main area of Phase 2 (Mining Area 2) can proceed after Mining Area 1 is excavated. �1 Dewatering will occur into Mining Area 1 to remove sediment before discharge. Discharge may be pumped -1 across drainage channel to Phase 1 or discharged to adjacent drainage channel. If discharged to drainage �1 channel, a series of checkdams will be installed to reduce flow velocity and remove additional sediment. All pit slopes will be mined to a maximum grade of 3:1 and composed of native, unmined material. No slopes adjacent to the groundwater barrier wall are allowed to be constructed of backfill. Do not mine closer than 200' 1 from nearby buildings. 1 4. Mining of the main area of Phase 2 will remain north of the Mining Area 1 /Mining Area 2 boundary until such time as the streambank stabilization structures have become established and can protect the bank from major erosion. (Minimum 300 foot setback from river during this period.) 1 1 5. Topsoil and overburden from Phase 2 will primarily be used in the backfilling of Phase 1. Overburden from 1 Phase 2 can be used to build sediment basin barrier berms in Phase 1 or be deposited as fill. Topsoil will not 1 be used as fill but only as topdressing on backfilled areas that are ready for final revegetation. 1 6. Once the streambank stabilization structures are established and effective, mining into Mining Area 3 may 1 proceed. It is desirable to construct a sturdy flood barrier along the south side of the Phase 2 area to help keep t flood waters from the river from overflowing into the pit and eroding the pit wall and possibly damaging the { groundwater barrier wall. Such a berm may require prior approvdi from FEMA as a berm will constrict the floodway of the river. .4605.1 - \ .44 Ka 6.9 .4605.2 1 4603.21 Q .46 .4 .1 . �l SETBACK FROM RIVER UNTIL STREAMBANK STABILIZATION IS FUNCTIONAL 7. The Reserve Overburden Supply in the northern part of the operation should be left undisturbed unless absolutely needed to complete backfilling of Phase 1. Exacavation of this (overburden may not extend lower than the elevation of the high point of the pit wall to the south. 8. No overburden or soil may be stockpiled between the Affected Land Boundary and the river. The only disturbance allowed in this setback is that needed to access the streambalnk for installation of streambank stabilization structures. Preserve tree and shrub growth as much as possible. 9. Setbacks from adjacent property owners will be a minimum of 25 feet. No mining may occur within 200' of nearby buildings on other property. No excavation of any kind may occur iin this setback zone. However, this zone may be used as the outer boundary area for the installation of the groundwater barrier wall. Where possible, larger setbacks than 25 feet are desirable to reduce the possibility of headward erosion encroaching into adjacent property. PRE-MINING TOPOGRAPHY -- -- - AFFECTED LAND BOUNDARY TREE LINES (PREMINING) ------- - - - - -- GROUNDWATER BARRIER WALL (SLURRY WALL) APPROX: 7 1 00' LONG; 67 ACRES ENCLOSED PIT WALL CONTOURS - .............. PROPERTY BOUNDARY (10' CONTOURS EXCEPT FOR (WHERE NOT CONGRUENT WITH PERMIT BOUNDARY) SLOPE CREST AND BASE CONTOURS) eeeeeee�.leeeeeeeeee -ems PERMIT BOUNDARY The Affected Land Boundary for Phase 2 actually includes the drainage between Phase 1 and Phase 2. No land between the south affected land boundary and the river may be disturbed except for installation of streambank stabilization measures. Preserve tree and shrub growth as much as possible in the river setback. (See Exhibit D - Mining Plan for more details on affected land definitions.) Permit #_ Confidential? M Class Type Seq �? -a3 M V# - Inspection Date - Doc Date (if no date stamp) To er Recipients 5L4 Revised - 01 107 Amendment: 3 Add Phase 2 scale: 1 " = 300' contour interval = 2' Continental Materials (M- 1986 -015) East Pit - Transit Mix of Pueblo EXHIBIT C -4C - PHASE 2 DETAIL MINING PLAN Mining topo without any reclamation applied Dl by: C4C •emend 3 PMee 2 De181 e1B0.d1Yo RECEI� f -' JAN 312007 Division of Reclame.'on, Mining and Safety