PERMFILE121682

• Permit No: C1980007A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: Exhibit 66 Small Area Exemptions for Sylvester Gulch Facilities
• Media Type: D
• Archive: Yes

February 27, 1997 -4- 963-2178
debris) of leaves and sticks, grasses, and oak brush root system of the undisturbed natural
vegetation slopes was taken as being equivalent to a grass filter of the following description:
Manning's "n" = 0.01 (approximately the middle of the allowable range,
nearly equivalent to a dense stand of fescue); spacing = 0.2" (The
distance is taken as representative as the spacing between leaves, grass
stems, and other debris of the ground cover.); height = 2" (a
representative depth of ground litter); stiffness = 2 (equivalent to a stand
of Bermudagrass, Retardance Class B/C); and an infiltratidn rate = 0.05
(lowest of a hydrologic soil profile of "C"). '
RESULTS
SedCAD+ demonstration computer printouts are attached. Refer to Maps 53B and 54B, and
Exhibits 66 and 69 for SAE Facility designations and locations.
The SedCAD+ demonstrations provide information on the Peak Settleable Concentrations
expected in effluent from the vegetative debris filters. The grass filters and resulting
settleable solid concentrations are st~mn+ari~ed in the following table.
. TABLE 5
SILT FENCE/STRAW BALE FILTERS AND
PEAK SETTLEABLE CONCENTRATIONS
....... .................... ..... Gonce~atiue: of :Peak::::::.;

::.::.::.::.:;:;:.:;::::~:,:<>;:::..: ;:-:.: _.:::.;::::.
:::.::... ;....::.; •;;::,:;:::.,::::::;:.:;::;:.:;:,;::.:::;.
:.
::.:::.:: Slieii
l F71ter:`:s::: ,?:`Setileable'Solids">:(
'=i ....
........

>.:.::s:::';:':'::::.::;':_::_'<::::>?:::::::
:...:.................,.......:......,.:.:

'::::::::':;<::,;::';;;:t:;::::::;;i?'..
............:.:...................:......... ~....

. ;:::Will >:

.... tit....
..:.:..... ..... ::s;Lei! h:.:

....
.......... t;t..:::
r;
.:<::.ellIttent'itrorttHtte
.:. 4....:...:...:.:..:..:..:..:...:..::,::,:
;:s:.:.:;SAB:Fa ::.:: : : :::::.:::. Fikeelocahan.':'':';: ss ': '::": feet::':::' :: eet ,:::: s:::.:':;,; .::!•.:::' :::::;::::<:':':: _:;': _':::'...
Topsoil Storage tce of slope of the pile 400 200 0.00
Pile ql
Topsoil Storage Pile A`2 tce of slope of the pile 450 50 0.00
plus Subsoil Storage Pile
Topsoil Storage tce of slope of the pile 300 100 0.17
Pile N3
Topsoil Storage tce of slope of the pile 400 500 0.00
Pile q4
Cut Slope above east and dovmgradient of 200 100 0.00
Substation, and dte cut slope
Substation
CONCLUSIONS
~• This SedCAD+ analysis review demonstrated that discharges from all sites will meet the
effluent SSp standards of 0.5 ml/l following a 10-year, 24-hour storm event. However, if
e~ee~ss~ne~zn~i.a un Golder Associates