SW6110103_Supplement Form_20110201

Permit
(to be provided bye w�Q�;
WW nT ®RSTORMWATER MANAGEMENT PERMIT APPLICATION FORMh
NC®ENR 401 CERTIFICATION APPLICATION FORM o
INFILTRATION TRENCH SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part III) must be printed, filled out and submitted along with all of the required information.
Project name
Contact person
Phone number
Date
Drainage area number
Drainage area
Impervious area
Percent impervious
Design rainfall depth
Peak Flow Calculations
1-yr, 24-hr rainfall depth
1-yr, 24-hr intensity
Pre -development 1-yr, 24-hr discharge
Post -development 1-yr, 24-hr discharge
Pre/Post 1-yr, 24-hr peak Flow control
Storage Volume: Non -SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
1.5' runoff volume
Pre -development 1-yr, 24-hr runoff volume
Post -development 1-yr, 24-hr runoff volume
Minimum volume required
Volume provided
Soils Report Summary
Soil type
Infiltration rate
SHWT elevation
Trench Design Parameters
Drawdown time
Perforated pipe diameter
Perforated pipe length
Number of laterals
Stone type (if used)
Stone void ratio
Stone is free of fines?
JSOC, SOF C4 Facility ILI 66362)
Jason Sesler
[phone]
1/20/2011
Drainage Area #1
85,000.00 ft2
58,400.00 ft2
68.7% %
1.00 in
3.Zu in
5.22 inlhr
/s ft'Isec
0.15 ft3/sec
-1.60 ft3/sec
4,750.00 ft3
6,991.00 ft3
ft3
ft3
ft3
ft3
ft3
Wagram
0.30 in/hr
235.50 fmsl
3.29 days
N/A in
N/A ft
N/A
#57 Stone
04
OK for non -SR waters
OK
Y (Y or N) OK
FES 0 8 2011
i
i
.° SEAL
3-4177F;
llilll'�t1�
Fonn SW401-Infiltration Trench-Rev.4 Parts I. & II. Design Summary, Page 1 of 2

Permit
(to be provided by DWQ)
Trench Elevations
Bottom elevation
244.00
fmsl OK
Storage/overflow elevation
246.65
fmsl
Top elevation
248.63
fmsl
Trench Dimensions
Length (long dimension)
110.00
ft
Width (short dimension)
32.00
ft
Height (depth)
4.63
ft OK
Additional Information
Maximum volume to each inlet into the trench?
0.52
ac-in
OK
Length of vegetative filter for overflow
60.00
ft
OK
Number of observation wells
3
OK
Distance to structure
>15
ft
OK
Distance from surface waters
>100
ft
OK
Distance from water supply well(s)
>100
ft
OK
Separation from impervious soil layer
>2
ft
OK
Depth of naturally occuring soil above SHWT
8.00
ft
OK
Bottom covered with 4-in of clean sand?
Y
(Y or N)
OK
Proposed drainage easement provided?
Y
(Y or N)
OK
Captures all runoff at ultimate build -out?
Y
(Y or N)
OK
Bypass provided for larger storms?
Y
(Y or N)
OK
Trench wrapped with geotextile fabric?
Y
(Y or N)
OK
Pretreatment device provided
3rass Channels, Inlets, Vortech (Water Quality) Chambers
Form SW401-Infiltration Trench-Rev.4 Parts I. & 11. Design Summary, Page 2 of 2

Permit
(to be provided by OWQ)
III. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
n' als Sheet No. {LAOS
<56 I os' 1. Plans (1" - 50' or larger) of the entire site showing:
C —5-1$ - Design at ultimate build -out,
- Off -site drainage (if applicable),
- Delineated drainage basins (include Rational C coefficient per basin),
- Trench dimensions,
- Pretreatment system,
- High flow bypass system,
- Maintenance access,
- Proposed drainage easement and public right of way (ROW),
- Overflow device, and
PLIVS - Boundaries of drainage easement.
c-SOIr c-s t o 2 Partial plan (1" = 30' or larger) and details for the infiltration trench showing:
6-'1 R1 C6) 0S - Bypass structure,
- Maintenance access,
- Basin bottom dimensions,
- Basin cross-section with benchmark for sediment cleanout,
- Flow distribution detail for inflow,
- Vegetated filter, and
/) I P%9rJ5 -Pretreatment device.
5�03. Section view of the infiltration trench (1" = 20' or larger) showing:
-Pretreatment and treatment areas, and
G9u4 dOl+9Jt -Inlet and outlet structures.
6-g-06 �f4. A table of elevations, areas, incremental volumes & accumulated volumes to verify the volume provided.
S6q�oJ�/ 5. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The
results of the soils report must be verified in the field by DWQ, by completing & submitting the soils
PLA rlS investigation request form. County soil maps are not an acceptable source of soils information.
a 10 ( 6. A construction sequence that shows how the inftlration basin will be protected from sediment until the
entire drainage area is stabilized.
6"gL.CS 7. The supporting calculations.
q i7AArg 8. A copy of the signed and notarized operation and maintenance (0&M) agreement.
N1q 9. A copy of the deed restrictions (if required).
Form SW401-Infiltration Trench-Rev.4 Part III. Required Items Checklist, Page 1 of 1