PERMFILE41049

• Permit No: C1981008A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: Pond 004
• Section_Exhibit Name: NH1 TAB 13 ATTACHMENT D Part 2
• Media Type: D
• Archive: Yes

LJ
TABLE 3
Spillway Data Summary
Sediment Fond 004
Principal Spillway: Type Riser Inlet (CMP)
Orifice Diameter 5/8-inch
Inlet Elevation. 5661.3
10-year, 24-hour Peak
Stage. 5663.27
Emergency Spillway: Type Drop Inlet (CMP)
Barrel Diameter 12.000-inch
Riser Diameter 12.000-inch
Length of Barrel 70.000-ft
Vertical Head Drop 7.0-ft
Entrance Loss Coef. 1.000
Bend Loss Caef. 0.500
Wier Coef. 3.100
Orifice Coef. 0.600
Manning Coef. O.G25
Inlet Elevation. 5665.2
25-year, 24-hour Peak
Stage. 5665.56
The entrance to the emergency spillway is located more than one foot
above the principal spillway. There will be no flow through the
• emergency spillway inlet as a result of the runoff from a 10-year,
24-hour precipitation event or less.
Construction Summary
In accordance with Rule 4, Part 4.05.6(7) of the Rules and Regulations
of the Colorado Mined Land Reclamation Board pursuant to the Colorado
Surface Coal Mining Reclamation Act 34-33-101 et seq., I, James Gary
Schlenvogt, hereby certify that the construction of Sedimentation Pond
004 was inspected and constructed under my supervision. From October 21
until November 4, 1987 during construction, I was on site to inspect and
supervise construction of this structure. I, James Gary Schlenvogt, am
a 1975 graduate in civil engineering and I have been a Registered
Professional Engineer in Colorado since October 17, 1980.
The purpose of my inspection and certification was to ensure proper
construction of Sedimentation Pond 004 and to satisfy the requirements
of Rule 4.05.6(7) of the Colorado Mined Land Reclamation Division. The
• material was placed in the embankment to meet or exceed the design
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