My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
PERMFILE110843
DRMS
>
Back File Migration
>
Permit File
>
200000
>
PERMFILE110843
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
8/24/2016 10:07:32 PM
Creation date
11/24/2007 8:03:32 PM
Metadata
Fields
Template:
DRMS Permit Index
Permit No
C1981014
IBM Index Class Name
Permit File
Doc Date
12/11/2001
Doc Name
TR-8 , TR-9 to TR-13??
Section_Exhibit Name
EXHIBIT 15 Part 7
Media Type
D
Archive
No
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
99
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
View images
View plain text
** Sedimentation Pond No. 4 contains a small undisturbed area surrounding <br />• the pond and the pond's water surface area in addition to the disturbed <br />and undisturbed watersheds contributing to the refuse collection ditches. <br />A curve number was determined for each. <br />*** Magpie Creek Diversion receives runoff from two (2) large undisturbed <br />subwatersheds. Due to their size, curve numbers were calculated <br />separately for each sub-basin based on soil and vegetation types. <br />As previously mentioned, computer (SEDCAD+) printouts for all mine area <br />structures are contained in the respective design calculations sections of <br />this exhibit. These printouts contain all hydrologic input values and <br />calculated peak flow values on a subwatershed basis for each structure. <br />Once peak flow values are calculated by SEDCAD+, Mannings Equation for <br />open channel flow was utilized to size the diversions and ditches. <br />Q = 1.486 ARz~3S~~Z <br />• n <br />Where Q = peak discharge for desired storm event (cfs) <br />n = Mannings roughness coefficient <br />A = cross sectional area of channe] flow (ftZ) <br />R = hydraulic radius (ft) <br />S = channel slope (ft/ft) <br />A Mannings roughness coefficient of 0.04 was used corresponding to an <br />earthen channel with some weeds and stones (Barfield et. al., 1981, page <br />159). <br />For channel sections with flow velocities exceeding 5.0 feet per second <br />rock riprap is, or will be, installed. The following equation is used to <br />determine riprap size. <br />• <br />9 R Revised - December, 1991 <br />
The URL can be used to link to this page
Your browser does not support the video tag.