NCC213685_NOT Closeout Documents (2)_20220622

Sand Filter
On
Record of Construction
Engineer's Certification of Completion
GREENSBORO
Project: AutoZone - 4626 Hicone Rd
Water Resources Department
Stormwater Management Division
2602 S. Elm -Eugene St.
Greensboro, NC 27406
[phone]
Date: 5/3/2021
Description
Design
As -built
I
Sand Filter Type
Open -Bottom
Open -Bottom
2
Sediment Chamber Specifications:
a
Sediment Chamber bottom elevation
823.50
823.0
b
Sediment Chamber depth
1.5' (WQv)
2.0' (WQv)
c
Sediment Chamber surface area (ft)
1,000 sf
1,100 sf
d
Sediment Chamber volume (ft)
1,665 cf WQv
2,300 cf WQv
3
Sand Filter Chamber Specifications:
a
Elevation at top of filter media
823.50
823.2
b
Depth of filter media
1.25'
1.3'
c
Filter bed area
1,250 sf
1,200 sf
d
Volume
2,035 cf (WQv)
2,200 cf (WQv)
e
Type & size of filter media
3" Depth
River Stone
12" Depth
Washed Sand
3" Depth
River Stone
12" Depth
Washed Sand
4
Percent of water quality volume stored in
sediment chamber & facility
45%
55%
51 %
49%
5
Underdrain System Specifications:
a
Size & type of perforated pipe
4" PVC
4" PVC
b
Type (of stone) and thickness of filters
around perforated pipe
9" #57
Stone
9" #57
Stone
c
Number of branch lines
2
2
d
Invert elevation of underdrain
821.50
821.3
e
Invert elevation of outflow pipe at
outlet
821.00 (Storm Pump)
824.00 (OCS, 18" Out)
820.9 (Storm Pump)
824.1 (OCS, 18" Out)
f
Invert elevation of receiving storm
sewer / receiving stream water surface
823.50 (M.H. #10)
823.5 (M.H. #10)
g
Depth of gravel jacket
6"
6"
6
Invert elevation of overflow / bypass
structure
826.50 & 827.50
826.2 & 827.2
7
Dissipator pad length & width
70' Level spreader; 824.00
70' level spreader; 823.5
8
Maintenance access provided (Yes / No)
Yes
Yes

Sand Filter
Record of Construction
L%0& Engineer's Certification of Completion
GREENSBORO
Water Resources Department
Stormwater Management Division
2602 S. Elm -Eugene St.
Greensboro, NC 27406
[phone]
ENGINEER'S CERTIFICATION OF
STORMWATER CONTROL COMPLETION
I certify that, pursuant to generally accepted engineering standards in the community, it is my
professional opinion that the stormwater control(s) labeled as Sand Filter on this plat (or on
name of plat) as recorded in PB 203 , PG 76 in the Office of the Guilford County Register
of Deeds has been completed in conformance with the plans and specifications approved on
06/04/2020 , has its full design volume available, and is functioning as designed.
P.E. SEAL:
SIGNATURE: DATE: