2008-12-10_REVISION - C1981010

• Permit No: C1981010
• IBM Index Class Name: Revision
• Doc Date: 12/10/2008
• Doc Name: Trapper G-Pit Landslide Mining Assesment
• From: Agapito Associates Inc
• Type & Sequence: PR6
• Media Type: D
• Archive: No

Ju»utir-v 15, 200x'
4.2.3 Geoinco- •
Page 18
The model section was taken through the point 1,435,500E, 404,500N, at 7,400 ft
elevation (local coordinates 55001, 4500N, 7,400) along a N70°E direction. The boundary of
the model extended from 5.495E to 7,665E. The model depth goes from the irregular
topographic ground surface down to an elevation of 6,750 ft. The geometry of the spoil pile
examined slope angles of 52° (1 H: 1.3V). 4-5`(114: 1 V), 40° (1.211:1 V), and 37.6" ( 1.311:1 V).
4.2.4 Vw rial Prolwi-ties
The same twenty-three material layers simulated in the G-Pit landslide FLAC31) model
analysis were used for this model. The assumed deformation and strength properties are shown
in Table 4 for each rock layer. The Mohr-Coulomh constitutive model was assigned to all layers.
The ubiquitous-joint constitutive model was assigned only to the Q-Floor mudstone layer. The
bedding of the Q-Floor mudstone assumed initial strength values of zero cohesion and tension,
and 15 " friction. The bedding strength in the Q-Floor mudstone assumed 15° for peak strength
and for 5° residual strength. The strain-softening behavior of spoils assumed peak friction
strength of 40° and residual friction strength was 30° for inelastic strains greater than 5°'o.
Table 4, Mechanical Properties Used in the G-Pit Spoil Stability FLAG' Model

Layer

Strata
Density
(Ih/ft') ) oung'
Modulus, E
(psf x 10")
Poisson'
Ratio RM
Cohesion
(ksf) R11
Friction
(°) R31
Tensile
(ksf)
1 013, MS 134.2 26.4 0...' 2.5 15.9 1.5
2 11 Seam 80.9 16.2 0.34 3.9 28.6 1.0
3 11 Floor, tiff 131.8 79.7 0.23 17.6 43.1 5.0
4 11 Seam 80.9 16.2 0.34 7,9 18.2 0.7
5 11-12 Inch. SS 130.5 79.7 0.23 25.0 40.6 6.7
6 12 Scam 80.9 16.2 0.34 16.7 18.7 1.4
7 12-K Inth, SS 144.8 120.0 0.18 36.8 29.0 3.7
8 MK Seam 79.8 16.2 0.34 21.0 17.1 1.6
9 MK Floor. MS 153.7 9.1 0.40 35.5 14.4 2.4
10 M1. Roof. MS 135.7 9.1 0.40 11.9 3.4 0.8
11 111. Seam 83.6 23.4 0.32 25.3 15.9 1.6
12 111. Floor. NIS 133.7 45.1 0.40 21.3 6.1 3.9
13 M1. Floor, SS 156.6 418.7 0.17 98.9 33.7 65.9
14 I.-M Inlb. Mti 145.8 48.1 0.37 55.7 19.9 8.9
15 M Roof. SS 133.9 190.7 0.17 67.0 23.7 16.9
16 M Rool, NIS 138.0 48.1 0.37 51.6 8.9 12.5
17 ki Seam 80.9 24.4 0.27 33.1 14.7 1.7
18 M Floor. MS I itl.6 48.1 0.37 61.9 11.3 30.2
19 U Scutt 80.7 24.4 0.27 34.8 ) 6.6 3.2
20 Q Floor. MS 134.8 48.3 0.37 35.1 5.8 5.1
21 Q Floor. SS 132.1 40.8 0.38 64.2 20.0 1.8
22 R Seam 811.9 25.1 0.27 23.3 8.8 0.6
'_ • R F lour, tiff 152.3 711 0.24 91.3 25.8 6.0
125 1.9 0.35 0 55 0
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