PERMFILE47451

• Permit No: C1980007A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: Exhibit 51 Lower Refuse Pile
• Media Type: D
• Archive: Yes

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III IIIIIIIIIIIII III
s99
l .0 INTRODUCTION ...................
2.0 DESCRIPTION OF PILECONF[GURATIONANDPHASING .............................. _.......................3
2.1 Current Lower Refuse Pile Configuratioa ............................._........................ ...._...................3
2.2 Final Lower Refuse Pile Configuration(RevisedMsrch, 1996) ....................... ......._................3
2.3 Phasing .............................._............................_............................_............... ............._...........4
2.3.1 Phase I .............................._............................_............................_..... ......................._4
2.3.2 Phase ll .............................._..:........................._............................_... ...........................4
2.3.3 Phase 111 .............................._............................_............................_.. ..........................4
2.3.4 PhaselV .............................._............................_............................_.. ...........................4
2.3.5 Phase V .............................._............................_............................_... ..........................5
2.4 StorageCapaciry .............................._............................_............................_. ..........................5
2.5 Materials Balance .............................._............................_............................_ .........................b
2.6 HighwayRight-of-Way .............................._............................_..................... ......._.................7
3.0 SOIL COVER VARIANCE ....
............ _ ...................8
4.0 TOPSOIL AND SUBSOIL SALVAGE AND STORAGE .............................._............................_...9
4.1 Topsoil and Subsoil Salvage .............................._............................_............................_.........9
4.2 Topsoil Storage .............................._............................_............................_.............................9
4.3 Subsoil Storage .............................._............................_............................_.............................9
5.0 GEOTECHNICALSTUD[ES .............................._............................_.......................... .._..............II
5.1 Field Investigation .............................._............................_............................_.... ...................1 I
5.2 Laboratory Results .............................._............................_............................_... ...................12
5.3 Geology .............................._............................_............................_..................... ......._........12
5.4 Subsurface Hydrology .............................._............................_............................ _.................13
5.4.1 Permeability Data .............................._............................_........................ ...._............13
5.4.2 Leachate Data .............................._............................_............................_ ..................14
5.4.2.1 Leachate Estimate Performed for Phases I through IV ................... ..........._....14
5.4.2.2 Leachate Estimate Performed for Phase V .............................._.... ...................16
5.4.3 Leachate TestingResults .............................._............................._.............. .............._.16
5.4.4 Water Quality of the North Fork of the Gunnison River ............................. ._...............17
5.4.5 Underdrains .............................._............................_............................_.. ...................18
5.5 Slope Stabilirv Analysis of Phases I through 1 V .............................._.................... ........._........ 18
S.~.i Critical Sections ............................._............................_........................... ._...............i8
x.5.2 Parameter Selection .............................._............................._..................... ......._.........19
5.5.3 PiezometricPressure .............................._............................._................... ........._.......20
5.5.4 Analyses Results .............................._............................_.......................... .._.............21
5.6 Slope Stability Analysis of Phase V .............................._............................_........ ..................21
5.6.1 Critical Sections .............................._............................._. ~~
5.6.2 Parameter Selection .............................._............................_..................... ......._.........23
5.6.3 AnalysesResults ..............................._............................_.......................... ..._..............24
6.0 SURFACE HYDROLOGY ..............................._............................._...........................~_ ..................25
6. I Introduction ..............................._............................_............................._............. ..............._. 25
6? Sediment Control Ditches .............................._............................_....................... ....._...........25
6.2.1 Sediment Control Ditches for Phases 1 through IV .............................._..... ..................25
6.2.2 Sediment Control Ditches for Phase V .............................._....................... ....._...........26
6.3 DesignafSedimentControlPond .............................._............................_.......... ...................26
6.3.1 Sediment Control Pond for Phases I through IV .............................._........ ...................26
Doc Date:12/11I2001
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