2009-09-21_PERMIT FILE - C1981010A ‎(34)‎

• Permit No: C1981010A
• IBM Index Class Name: Permit File
• Doc Date: 9/21/2009
• Doc Name: Cost Summary
• Section_Exhibit Name: Appendix A Circes Cost Estimate
• Media Type: D
• Archive: Yes

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CIRCES Cost Estimating Software
SURFACE BLASTING WORK
PROJECT IDENTIFICATION
Task # : 022 State : Colorado Permit/job #: C-1981-010
Date : 0710712009 County : Moffat Abbreviation : none
User: JDM Site : Trapper Mine Filename : C010-022
Agency or organization name : Colorado Division Of Reclamation, Mining And Safety
Permit or other job action :Permit Revision 06
Task description : Cast Blast East A-Pit
BLAST AREA DIMENSIONS
QUANTITY UNIT
Blast area configuration description Wedge-shaped mass
Blasting method description Cast blast
Highwall or bench face angle 0.71 h:1v
Regraded slope angle 3.00 h1 v
Highwall or bench length 1,850 feet
Highwall or bench width (from vertical line at base of desired cut on highwall face) 75 feet
Highwall or bench height (from pit floor to crest) 150.0 feet
Depth to base of cut at highwall face 25.0 feet
BLAST AREA VOLUMES
Total volume of dimensional mass to be shot
Blast volume to subdrill grade and blast pattern lines
Blast volume to finish grade and blast pattern lines
Remaining volume required to be re-shot or ripped
BLAST AREA DESIGN
QUANTITY UNIT
49,034 cubic yards
44,236 cubic yards
44,236 cubic yards
4,797 cubic yards

QUANTITY UNIT
Recommended blasthole diameter 3.33 inches _
Selected blasthole diameter 9.00 inches
Subdrilling allowance 0.0 feet
Blasthole depth (avg. depth of holes on wedge-shaped mass) 11.6 feet
Density of rock Cast blasting (AN rock density _
Burden to Charge Diameter Ratio 20 times diameter
Burden 15.0 feet
Spacing to Burden Ratio 1.1 times burden
Spacing 17.0 feet
Cubic yards of rock per blasthole (avg. quantity per hole on wedge-shaped mass) 102.40 cubic yards
Powder factor description Cast blasting rock strength
Powder factor 2.150 pounds/cu.yd.
Density of blasting agent 0.85 grams/cc _
Quantity of explosives per blasthole (avg. quantity per hole on wedge-shaped mass) 220.16 pounds
Height of powder column per blasthole (avg. height per hole on wedge-shaped mass) 9.39 feet
Height of stemming per blasthole (avg. height per hole on wedge-shaped mass) 2.19 feet
Stemming to burden ratio (avg. ratio per hole on wedge-shaped mass) 0.15 times burden
Quantity of stemming per blasthole (avg. quantity per hole on wedge-shaped mass) 0.0359 cubic yards _
Number of rows 4 rows _
Number of blastholes per row 108 holes per row_
Total number of blastholes 432 holes
Total length of all blastholes 5,004 feet