PERMFILE123290

• Permit No: C1980001
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: RATIONALE FOR SEDIMOT II INPUT PARAMETERS
• Section_Exhibit Name: 4.6 Appendix 4.6-M‎(b)‎
• Media Type: D
• Archive: No

Doc Date:1 211 112 0 01
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RATIONALE FOR SEDIMOT II INPUT PARAMETERS
I. In preparing the Sedimot II tercace outputs the following parameter
values were used to obtain output values listed in the worksheet summaries.
(A). Stnrm i nk
(1). Storm Type - SCS's Type 2 which is the Sedimot !I default
value.
(2). Rainfall depth and duration - Based on 10 year (1.80")
24 hour precipitation event. This rainfall depth and
duration value was obtained from section 2.5-4 of the
approved Edna Mine Permit Application.
(3). Time Increments -One-tenth (1/10) of an hour was
considered an acceptable value of time for these size
watersheds by the originator of Sedimot II, (University of
Kentucky).
(B). Watershe d Data
Watershed data - Watersheds were dissected using the
map illustration shown on Exhibit 4.6-M3.
(C). Between Structure RoutinE Parameters - Between structure
routing parameters were derived from calculations
obtained in worksheet 1 in Appendix 4.6-M(b).
• (D). Hydraulic Input Values For Subwatersheds -The area for water-
sheds was planimetered for acres and the curve numbers
derived from values listed in Table 2.20, The Aoolied
gydroloev afld Sedimentoloev E4.C Disturbed Areas,
Ba~eld, Warner and Haan, Oklahoma Technical Press 1981.
(1). Curve No. 79 - Represents range land in poor condition.
(Spoils)
(2). Time of Concentration - Derived from calculation
on worksheet I & II contained in Appendix 4.6-M(b).
(3). Travel Time - Derived from calculation on
worksheet I & II of Appendix 4.6-M(b).
(4). K Value -Derived from calculation on worksheet I
& II of Appendix 4.6-M(b).
(5). X Value -Derived from calculation on worksheet I &
II of Appendix 4.6-M(b).
(E). Unit Hydrograph - Based on an agricultural condition.
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