2013-10-07_PERMIT FILE - C1981025A ‎(6)‎

• Permit No: C1981025A
• IBM Index Class Name: Permit File
• Doc Date: 10/7/2013
• Doc Name: Final Engineering Calculations
• Section_Exhibit Name: 4.0 Appendix 4-B
• Media Type: D
• Archive: Yes

• LONG POND SPILLWAYS
DISCHARGE THOUGH A SUBMERGED TUBE
DIAMETER OF PIPE
AREA OF PIPE
C = LOSS COEFFICIENT
H = HEAD ON SPILLWAY
Q = C A (2GH)^.5
Q =
Q = ONE 4-INCH PIPE _
Q = TWO 4-INCH PIPES =
4.000 INCHES
0.0872 SQUARE FEET
0.500
0.167 FEET
3/6
0.1429 CUBIC FEET PER SECOND
64 GALLONS PER MINUTE
128 GALLONS PER MINUTE
DISCHARGE THOUGH A SUBMERGED TUBE
DIAMETER OF PIPE 6.000 INCHES
AREA OF PIPE 0.1963 SQUARE FEET
C = LOSS COEFFICIENT 0.500
H = HEAD ON SPILLWAY 0.250 FEET
Q = C A {2GH)^.5
Q = 0.3937 CUBIC FEET PER SECOND
Q = ONE 6-INCH PIPE = 177 GALLONS PER MINUTE
Two 4 inch emergency spillway pipes have adegate capacity to
handle the design flow of 70 gpm. In the event that the
25-year event did occur, the 0.077 acre feet of water would
be discharged through both the primary and emergency spillways.
It would take 6.5 hours to pass the 0.077 acre feet through
• one emergency spillway flowing at 64 gallons/minute,
(0.077*43560*7.48) Gallons /(64*60) Gallons/Hour.
Reference Civil Engineering Handbook,
Urquhart, Fourth Edition, Page 4-34.
The primary spillway will be a six inch diameter pipe. The
emergency spillway will be two four inch diameter pipes.
DIVERSION DITCH ABOVE TREATMENT PONDS T-1 AND T-2
Treatment ponds T-1 and T-2 are two of the three ponds
used to handle the No. 1 Mine drainage. This calculation
is presented to determine the size of ditch required to
divert surface drainage away from the ponds.
The flow will be calculated from two different drainage
areas. The first drainage area is the revegetated site
which has a curve number of 70 as explained above.
The second is the access road which has a curve number
of 82 based on the classification of Farmsteads-buildings,
lanes, driveways and surrounding lots, soil type C.
•
P-9-7
08-14-95