2008-08-06_REVISION - C1982057

• Permit No: C1982057
• IBM Index Class Name: REVISION
• Doc Date: 8/6/2008
• Doc Name: Midterm Review Reclamation Cost Estimate
• From: DRMS
• To: Seneca Coal Company
• Type & Sequence: MT5
• Email Name: DTM
• Media Type: D
• Archive: No

sheet 1 of 2
CIRCES Cost Estimatina Software
SURFACE BLASTING WORK
PROJECT IDENTIFICATION
Task #: 002 - State : Colorado PermitfJob #: C-1982-057
Date : - V08J05?2_008 County : Routt_ _ Abbreviation : none
User : -- JRS _ Site :Seneca !i-W -- ---- Filename : C057-002 --V
Agency or organization name : Colorado Division Of Reclamation, Mining And Safety
Permit or other job acfion :2008 Midterm Review -------
Task description : Drill and Shoot South Wadge Pit HighwaH
BLAST AREA DIMENSIONS
Blast area
method descri
QUANTITY UNIT
mass
blast

rtignwan or
ch face angle -

0.50 --
-
;h:1v
eg pe angle ----
1.00 ----- -
h:1v
Highwall or bench length - 5.250 feet
Highwal{ or bench width (from vertical line at base of desired cut on highwall face) 40 feet
Highwall or bench height (from pit floor to crest) i 10.0 feet
epth to base of cut at highwall face 40.0 fleet

BLAST AREA VOLUMES
QUANTITY UNIT
Total volume of dimensional mass to be shot 77, 778 !cubic yards
Blast volume to subdrill grade and blast pattern lines - - 73,684 cubic yards
last volume to firnsh grade and blast pattern lines
------. 62,151 ;cubic yards
_- - - - _
Remaining
volume required to be re-shot or ripped
139,929
cubic yards
BLAST AREA DESIGN
Recommended blasthole diameter
Selected blasthole diameter
QUANTITY UNIT
5.88 inches
ubdrilling allowance 63
:feet
_.------- -- depth (avg_ depth of holes on wedge-shaped mass) 26.3 feet
Density of rock - A verage Density R+rock density
Burden to Charge Diameter Ratio 25 times diameter
Burden 21.0 :feet
Spacing to Burden Ratio 1.1 times burden
----
Spacing -._
23.0 ._.
feet
Cubic yards of rock per blasthole (avg.
Re quantity per hole on wedge-shaped mass)
147.30 ? _....._ __ .._ _.._--
cubic yards
Powder factor description Medium rock strength

_
owder factor
--- ..
.. - -
0.575

pounds/cu yd.
. Density of blasting agent i 0.85 'grams/cc
Quantity of explosives per blasthole (avg, quantity per hole on wedge-shaped mass) 0.00 pounds
Height of
powder column per blasthole (avg height per hole on wedge-shaped-mass)
3.00
`feet
Height of stemming per blasthole (avg. height per hole on-wedge-shaped mass) 23.30 feet
Stemming to burden ratio (avg, ratio per hole on wedge-shaped mass ! 1.11 'times burden

-
_
Quantity of stemming per blasthole (avg. quantity per hole on wedge-shaped mass)
-_ _.._._ - --- 0.0000 cubic yards
- -

umber
of
rows - -
--
0 - - ---- ._.,

;rows
Number of bfasthoies per row 228 holes per row
Total number of blastholes 0 Tholes
Total length of all blasthofes 5,996 feet