2012-02-12_REVISION - M2005050

• Permit No: M2005050
• IBM Index Class Name: REVISION
• Doc Date: 2/12/2012
• Doc Name: REVISED DRAINAGE
• From: RIMROCK
• To: DRMS
• Type & Sequence: TR2
• Media Type: M
• Archive: No

r-
10YR
LOWER POND PLAN VIEW
1" -20'
LOWER SPILLWAY
100 -YR /24HR PEAK DESIGN FLOW - 7.24 CFS (Sum of Lower and
Upper 100 -YR Peak Flows)
Height of flow (Broad Crested Weir) -
H= (Q /CL)"2 /3
For C = 2.84, Q = 7.24 cfs, L = 96 in
H = 5.60 in, Spillway Elevation © 6636.60, Crest @ 6638.0
PAP 0790 RIPRAP DESIGN -
D50 Cu^1 /4= 0.55(gf"0.52 /S^3 /4)(sin a /(Gs cos a- 1)(cos a tan phi -sin a))�1.11
D50= (0.55(gf- 0.52 /S^3 /4)(sin a /(Gc cos a- 1)(cos a tan phi -sin a))�1.11) /Cur1 /4
FOR UPPER POND -
D50 = median stone size (m)
Cu = coefficient of uniformity = 1.95, of = unit discharge (m3 /m /s) = 0.084
S = embankment slope (unitless) = 0.333, a = embankment slope (degrees) = 18.43
Gs = specific gravity of riprap = 2.24, phi = angle of repose of the riprap = 42
D50 = 0.100M or 3.94in
LOWER BASIN - REQUIRED VOLUME -
10YR /24HR STORM
AREA DEPTH VOLUME
(AC) (IN - TR -55) (CU -FT)
3.000 0.773
ELEVATION AREA
6636.6
6636.0
6635.0
6634.0
6633.0
6632.0
4504.0
3473.0
2223.1
1288.4
786.4
202.1
LINE SPILLWAY THROUGH
-DAM WITH STONE OR SUITABLE
BLOCK TO PROVIDE VERTICAL
1 CHANNEL WALL 2
M
r- Varies -- - - - - --
8,420
CUMULATIVE - - - - - - - - - -
- - --
VOLUME (CONIC) - - - -
-- - - - - -- - - --
8435.5 \� \� \� \ %\� \� \ % \� \� \� \� \�\
\ \
6049.1
3224.1
1489.5 LATERAL SPILLWAY
462.4 SECTION (typ.,)
0.0 1• - 41
ALTERNATE RIPRAP FILTER -
6 INCH LAYER OF GRAVEL
WITH A MAX DIA OF 2 INCH
A D50 OF NO.4 AND A MIN.
OF NO. 100. O
F9Z9y
13
CREST - 6538.0 Sin LAYER - 1 -1/2 inch D50 Riprap
0 10YR WSEL -
6536.6
1
"'.�W - - -
--- - - - - --
MIRAFI 1120 or 1160N OR EQUIVALENT
RECEIVED
LOWER POND SECTION THRU SPILLWAY
19 -8r
For interstitial flow, Vi (flow velocity) _ (gD50)^0.5 *2.48s^0.58 *CUB -2.22
where s = slope in ft per ft = 0.333
Vi = ( 32. 16x( 6/ 12)) ^0.5x(2.48x(0.333)^0.58)x(1.95" -2.22) = 1.19 fps
Average velocity is the interstitial velocity multiplied by the porosity
(Np) of the riprap - Vav = Vi x Np.
for Np = 0.45, Vav = 1.19x0.45 = 0.54 fps.
Depth of flow is the flow quantity divided by the average velocity -
Y = Q /Vav, Y = (7.24/8ft.)/0.54fps = 1.69 ft. or 20.2 in., using
an integer multiple of D50 for thickness gives 4xD50 for 24 inches
of 6 in. D50 riprap.
Due to lower SG of sandstone (140 pcf - SG = 2.24) and to
provide a safety factor use a riprap with a D50 of 9 in.
Vi = ( 32. 16x (9/12))^0.5x(2.48x(0.333)^0.58)
x(1.95^ -2.22) = 1.46 fps
Vav = 1.46x0.45 = 0.66 fps.
Y = (7.24cfs /8ft) /0.66fps = 1.38 ft or 16.5 in, using
an integer multiple of D50 for thickness gives 2xD50
for 18 inches of 9 in D50 riprap.
_� _ 3 201Z
GRAND JUtvI,� i ovir r itLD OFFICE
DIVISION OF
LEGEND -
RECLAMATION MINING & SAFETY
BASIN BOUNDARY
BERM
DIVERSION SWALE
DITCH
SILT FENCE v
RIMROCK EXPLORATION & DEVELOPMENT
(BIRD MINE PERMIT 2005 -050 TECHNICAL REVISION C
REVISED DRAINAGE - LOWER POND DETAILS
DATE: 10/25/11 JAMES C. PIERCE, JR.
DRAWN BY: JCP, JR P.O. BOX 100
NUCLA, COLORADO 81424
SHEET 3 OF 3 (970) 864 -7455