2011-01-13_PERMIT FILE - C1981038 ‎(6)‎

• Permit No: C1981038
• IBM Index Class Name: Permit File
• Doc Date: 1/13/2011
• Section_Exhibit Name: Volume 1 4.03 Roads
• Media Type: D
• Archive: No

9.03 Rl0AD6
9.03.1 RdUl Roads. (Oont'd.)
a The Orchard Valley West Mine haul road has sufficient gravel surface baste
on the traffic weight rerluirements. 'This gravel surface was constructed
and is maintained to prevent ponding, and provide road surface stability.
The Orchard Valley R-0-M coal stockpile haul road surface is designed,
constructed, and maintained to prevent ponding of water, to provide
erosion control, and to provide road surface stability.
(4) (e) (i)
All culverts used in construction of the Orchard Valley Mine, Orchard
Valley West Mine, and Orchard Valley RAM coal stockpile haul roads have
an end area of less than 35 square feet. They are designed to safely pass
the 10-year, 24-hour precipitation event as shown in Surface Drainage
Appendix Volume 8, and Stability Analyses Appendix Volume 6. The original
design specifications utilized for the 48" culvert installed in Stevens
(filch beneath the orchard Valley R-O-M coal stockpile haul road are
unknown. Analysis of this existing culvert's hydraulic properties and the
associated watershed indicates the structure is adequate to safely pass
runoff from the 10-year, 24-hour precipitation event. The adequacy of
this particular culvert is further evidenced by the structural integrity
of the installation which has been maintained since 1976.
(4) (e) (ii)
• Culverts are placed using accepted engineering and construction practice.
No problems have resulted or are anticipated in culverts due to soil
pressure, passive resistance, or weight of vehicles.
(4) (e) (iii)
Culverts are installed with metal inlet and outlet structures where
rerniired. Also, grates are constructed as required to minimize plugging
of culverts.
(4) (e) (v)
All haul road culverts are covered by cortg~acted fill to a mini~mun depth of
1 foot.
(4) (e) (vi)
GUlverts were installed at the existing Orchard Valley Mine haul road to
accotmnodate flows from small intersecting drainages. Spacing of culverts
does not exceed 500 feet (refer to Map No.'s 8A-9A, 8A-9B, and 8A-9C).
Culverts were installed at the Orchard Valley West Mine haul road to
aocanmiodate flows from small intersecting drainages. Spacing of culverts
does not exceed 500 feet (refer to sheet 7 of the Orchard Valley West
Portals Designs in Volume 6).
• Culverts were installed at the existing Orchard Valley R-0-M coal
stockpile haul road to accommodate flows from small intersecting
drainages. Spacing of culverts does not exceed 500 feet.
'1'R 92-18 Revised 07/08/94
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