GENERAL41656

• Permit No: C1981037
• IBM Index Class Name: General Documents
• Doc Date: 12/13/1994
• Doc Name: DECISION ON CWL CLAIM PURCHASE ORDER C-79064
• From: DMG
• To: COLO WEST LEASING
• Permit Index Doc Type: GENERAL CORRESPONDENCE
• Media Type: D
• Archive: No

~ MAXIMUH GRADES FOR HAUL ROADS
Overall Pitch Permissable Length
Road Class Grade Y Grade S of Pitch Grade
Class 1 10 15 300 (Maximian .
length within
100 feet)
Class 2 10 15 300 (length)
III. TRANSYERSE GEOMETRY
The transverse geometry, the cross section of the road are
of great importance especially in ensuring good drainage
of the road and stable construction.
The Regulations specify the width of haul roads re-
quired. Skelly and Loy's report gives the following
design guide for vehicles up to 100,000 pounds gvw.
The width for 1-lane (23 ft.) and 2-lane (40 ft.) haul
roads on curves are shown in Table 2.
TABLE 2
RECOMMENDED UIDTHS FOR HAUL ROADS
Lurve Radius One-Lane Two-Lane
(Ft.• ) Haul Way Haul Way
25 27 48
50 25 44
100 24 42
200 23 41
"lln the inner edge of the pavement.
If the area upstream of the haul road is also disturbed,
rll runoff from the road must be passed through a 5edi-
rent basin (816.42]. Therefore it is Clearly best to
try to concentrate road grainage at a few selected
points. This will mean the use of roadside ditches,
usually located on the ups lope side of the road, with a
revere fall on the whole roadbed so that all drainage
flows to the ditch (Fig. 2). This will mean a culvert
under the road at each sag in the vertical profile.
In steep terrain where most haul roads will be on cut
and fill. a downslope dltch would have to be located
on fill (Fig. 3) and would 6e liable to washout unless
lined. The reverse fall also prevents overland flow
from upsl ope areas flowing onto the road. Cross-slope
to give rapid drainage of surface water should be >t-y"/
ft (10). However in flatter terrain such an arrange-
ment or a cambered road with a ditch on both sides is
possible when road is in total cut
ot=~opewnc
h.lh
0. -~
bPwn. ~a14=4~w"R.
nk b 5mle.
Figure 2
DA*hladalonFll
~svsLrpHkb lioahout •
~~
u ~ ~ _.
~•:if'' Or[proL
' 'y'
g3I`FWI.,'~'T~T~ ~ .
I OJth VuWvd an 4k.
Figure 3 rot~losca/a
Curves on haul roads should normally be superelevated
(banked) for greater safe-operating speeds. Super-
elevations will normally be banked Snto the slope of
the land at crests artd away at sags which allows most
drainage to be handled in ups lope ditches as suggested
above. The Regulations do not specify superelevations,
bui Skelly and Loy's report gives criteria for calcula-
ting superelevations necessary on high-speed haul roads.
The Regulations specify maximian slopes for cuttings
and embankments on haul roads for Class ! and fi roads.
These are shown in Tables 3 and 4.
TABLE 3
MAXIMUM CUT SLOPES FOR HAUL ROADS
Road Class Unconsolidated Ma terf al RDCk -
Class I 1v:1.5h 1v:0.25h
Class II 1v:1.5h 1v:0.25h
Class III no standards specified
TABLE 4
MAXIMUM SLOPES FOR EMBANKMENTS IN HAUL ROADS
Road Class Unconsolidated Fill Rock
Class 1 lv:2h 1v:1.35h
Class iI Iv:1.5h iv:1.35h
Class III no standardsClass Ill no standards s~cified
Topsoilin9 and temporary erosion control measures are
required for Class I and II roads in the performance
standards for slopes of 1v:1.5h or flatter (i.e. those
slopes not in rock or constructed of rock fill).
[V. DRAINAGE [816.153, 816.163 AND 816.173)
On Class 1 roads the drainage system must be designed
for a 10-yr, 24-hr precipitation event. Sedimentation
control for all classes of roads must comply with
Sections 816.42 and 816.45 requiring that all runoff
from "disturbed areas' be passed through sedimentation
ponds: however, Section 816.42(a)(4) notes that 'dis-
turbed areas" do not include those areas in which
only roads are installed if the area upstream of the
road is not "otherwise disturbed.' Matural drainage
channels may not be altered without the approval of
the RA and may not be altered at all in the case of
Class III roads. Drainage structures are required
for all stream crossings.
4:1 Ditches are required for Llass I road (on both
sides of a throughout and on the inside shoulder of
a cut-and-fill section). Ditches are not necessar-
ily required for Class [I roads where ditches,
GROUP MOBILIZATION AND MINING OPERATIONS HANDBOOK ~ •
FOR
MEASURES HAUL ROADS SMALL MINE
OPERATORS 2
a7