Laserfiche WebLink
J-2 Contracting Co.—DPG Pit— Technical Revision No. 1 Adequacy Review Response <br /> File No. M-2019-028 <br /> -6- <br /> Case 3 has been revised, using the previously approved soil strength parameters, to <br /> show the silt pond slope adjacent to the Cache La Poudre River to be 2:1, and to remove <br /> the slurry wall in that area. <br /> Case 4 has been revised, using the previously approved soil strength parameters, to <br /> show the silt pond slope adjacent to the gas line easement east of the Phase 1 silt pond <br /> at its original 3:1 slope this area, and to remove the slurry wall in that area. <br /> Both Cases 3 and 4 have been analyzed to comply with the factor of safety of 1.5 (static <br /> and rapid drawdown) and 1.3(seismic) for critical structures. <br /> Below are tables summarizing original soil properties used in the analyses, and the <br /> results for the revised Cases 3 and 4. <br /> Table 1 - Soil Properties <br /> Description Max dry density Saturated Density Cohesion Internal <br /> (pcf) WO (psf) Friction <br /> Angle <br /> Overburden 110 131 150 22 <br /> Sand and Gravel 110 125 0 35 <br /> Clay 107 130 50 24 <br /> Weathered 125 141 100 18 <br /> Bedrock <br /> Stable Bedrock 125 141 2000 20 <br /> Slurry Wall 100 110 0 45 <br /> Table 2 - Static Condition Slope Stability Analysis Results <br /> Description Calculated Required <br /> Factor Minimum Factor <br /> Of Safety Of Safety <br /> Case 3- Cache La Poudre River 2.39 1.50 <br /> Case 3- Cache La Poudre River Full Silt Pond 2.77 1.50 <br /> Case 4- Gas Line Easement 1.52 1.50 <br /> Case 4- Gas Line Easement Full Silt Pond 2.60 1.50 <br /> Table 3 - Pseudo-Static Condition Slope Stability AnalVsis Results <br /> Description Calculated Required <br /> Factor Minimum Factor <br /> Of Safety Of Safety <br /> Case 3- Cache La Poudre River EQ 1.76 1.30 <br /> Case 3- Cache La Poudre River Full Silt Pond EQ 1.78 1.30 <br /> Case 4- Gas Line Easement EQ 1.30 1.30 <br /> Case 4- Gas Line Easement Full Silt Pond EQ 1.79 1.30 <br /> Below are summaries and analysis conclusions for each revised case: <br /> V 305 Denver Avenue-Suite D•Fort Lupton CO 80621 •Ph: 303-857-6222•Fax: 303-857-6224 <br />