20100684 Ver 1_More Info Received_20101203

McGiU
A S S O C I A T E S
December 2, 2010
Mr. Joseph Gyamfi, PE
North Carolina Department of
Environment and Natural Resources
Division of Water Quality
401/Express Permitting Unit
2321 Crabtree Boulevard
Raleigh, North Carolina 27604

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J? 9f) @
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KETLAI,"E'SEAAMDIt'rF-R QUALITY
RE: Stormwater Review
Foothills Commerce Center - Phase One
Cleveland County, North Carolina
Dear Mr. Gyamfi:
Please find attached the Stormwater Plan and calculations for the proposed Foothills
Commerce Center - Phase One on Artee Road in Cleveland County for review. We have only
enclosed plan sheets that were revised to reflect the proposed stormwater measures to be
constructed as part of Phase One of this project. Sheets C-101 and C-701 show the stormwater
measures that would be constructed in the future if the conceptual plan was followed to buildout.
Please contact Becky Johnson, PE, or me if you have any questions or concerns.
Sincerely,
McGILL ASSOCIATES, P.A.
Tv ?' ?V?-VA-
RHONDA H. HONEYCUTT, El
Engineering Associate
Enclosures
cc: Mr. Rick Howell, City of Shelby (w/ enclosures)
Mr. Brad Cornwell, City of Shelby (w/ enclosures)
Mr. Dale Pennell, PE, McGill Associates, P.A.
P:\2009\09.00116\Letters\j g02dec l O.docx
E n g i n e e r i n g • P l a n n i n g • F i n a n c e
McGill Associates, P.A. - P. 0. Box 2259, Asheville, NC 28802 - 55 Broad Street, Asheville, NC 28801
828-252-0575 - Fax: [phone]

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ATA DEW
7,OLr
NCDENR
Permit No. I D- O (0 8 4
(to be provided by DWQ)
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
W A TF9pG
O Niii? 'r
I. PROJECT INFORMATION
Project name Foothills Commerce Center - Phase One
Contact person Brad Cornwell - City of Shelby - Public Utilities Director
Phone number [phone]
Date 16-Nov-10
Drainage area number 1
il:' DESIGN INFORMATION
Site Characteristics
Drainage area 962,240 ft2
Impervious area, post-development 201,012 ft2
% impervious 20.89 %
Design rainfall depth 1.0 in
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
Post-development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calculations
Is the pre/post control of the 1yr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre-development
Rational C, post-development
Rainfall intensity: 1-yr, 24-hr storm
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the perm. pool elevation)
Top of 1 Oft vegetated shelf elevation
Bottom of 1 Oft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state-required temp. pool?
Elevation of the top of the additional volume
19,085 ft3 OK
33,326 ft3
OK, volume provided is equal to or in excess of volume required.
ft3
ft3
ft3
ft3
ft3
(Y or N)
3.1 in
0.30 (unitless)
043 (unitless)
0.13 in/hr OK
0.86 ft3/sec
24 ft3/sec
0.38 ft3/sec
809.50 fmsl
807.50 fmsl
807.50 fmsl
808.00 fmsl
807.00 fmsl
802.90 fmsl
801.90 fmsl
1.00 ft
(Y or N)
fmsl
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & II. Design Summary, Page 1 of 2
Permit No.
(to be provided by DWQ)
If. DESIGN MIR MATION
Surface Areas
Area, temporary pool 19,322 ftz
Area REQUIRED, permanent pool 12,990 ftz
SA/DA ratio 1.35 (unitless)
Area PROVIDED, permanent pool, Apeonyoo, 13,053 ft OK
Area, bottom of 1 Oft vegetated shelf, AW shelf 10,736 ft
Area, sediment cleanout, top elevation (bottom of pond), Abotyond 5,800 ft`
Volumes
Volume, temporary pool 33,326 ft3 OK
Volume, permanent pool, Vpermyod 42,200 ft3
Volume, forebay (sum of forebays if more than one forebay) 11,178 ft3
Forebay % of permanent pool volume 26.5% % Insufficient forebay volume.
SA/DA Table Data
Design TSS removal 90 %
Coastal SA/DA Table Used? N (Y or N)
Mountain/Piedmont SA/DA Table Used? Y (Y or N)
SA/DA ratio 1.35 (unitless)
Average depth (used in SA/DA table):
Calculation option 1 used? (See Figure 10-2b) N (Y or N)
Volume, permanent pool, Vpenpod 42,200 ft3
Area provided, permanent pool, Aperm-pcd 13,053 ft`
Average depth calculated ft Need 3 ft min.
Average depth used in SA/DA, da,, (Round to nearest 0.5ft) ft
Calculation option 2 used? (See Figure 10-2b) Y (Y or N)
Area provided, permanent pool, Aperm_pW 13,053 ft`
Area, bottom of 1Oft vegetated shelf, Abot shelf 10,736 ft`
Area, sediment cleanout, top elevation (bottom of pond), Abotyond 5,800 ftz
"Depth" (distance b/w bottom of 1 Oft shelf and top of sediment) 4.10 ft
Average depth calculated 3.61 ft OK
Average depth used in SA/DA, da,, (Round to nearest 0.5ft) 3.5 ft OK
Drawdown Calculations
Drawdown through orifice? Y (Y or N)
Diameter of orifice (if circular) 4.50 in
Area of orifice (if-non-circular) in2
Coefficient of discharge (CD) 0.60 (unitless)
Driving head (Ho) 1.90 ft
Drawdown through weir? N (Y or N)
Weir type (unitless)
Coefficient of discharge (C.) (unitless)
Length of weir (L) ft
Driving head (H) ft
Pre-development 1-yr, 24-hr peak flow 0.86 ft3/sec
Post-development 1-yr, 24-hr peak flow 1.24 ft3/sec
Storage volume discharge rate (through discharge orifice or weir) 0.73 ft3/sec
Storage volume drawdown time 2.08 days OK, draws down in 2-5 days.
Additional Information
Vegetated side slopes 3 :1 OK
Vegetated shelf slope 10 :1 OK
Vegetated shelf width 10.0 ft OK
Length of flowpath to width ratio 3 :1 OK
Length to width ratio 2.0 :1 OK
Trash rack for overflow & orifice? Y (Y or N) OK
Freeboard provided 1.0 ft OK
Vegetated filter provided? N (Y or N) OK
Recorded drainage easement provided? Y (Y or N) OK
Capures all runoff at ultimate build-out? Y (Y or N) OK
Drain mechanism for maintenance or emergencies is: Portable pump
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & II. Design Summary, Page 2 of 2
Permit No
(to be provided by DWQ)
111. 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.
Page/ Plan
Initia s Sheet No.
C-108 1. Plans (1" - 50' or larger) of the entire site showing:
C-701 Design at ultimate build-out,
Off-site drainage (if applicable),
- Delineated drainage basins (include Rational C coefficient per basin),
- Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
- Proposed drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
$AN C
508 "
'
- 2. Partial plan (1
= 30
or larger) and details for the wet detention basin showing:
- Outlet structure with trash rack or similar,
- Maintenance access,
- Permanent pool dimensions,
- Forebay and main pond with hardened emergency spillway,
- Basin cross-section,
- Vegetation specification for planting shelf, and
-Filter strip.
T&L
-" "
'
9- C-508 3. Section view of the wet detention basin (1
= 20
or larger) showing:
- Side slopes, 3:1 or lower,
- Pretreatment and treatment areas, and
- Inlet and outlet structures.
N/A 4
If
h
.
t
e basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
Att
h
d 5
A
bl
f
l
ac
e .
ta
e o
e
evations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
C-509 6. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.

Attached 7. The supporting calculations.
Att
h
d 8
ac
e . A copy of the signed and notarized operation and maintenance (0&M) agreement.

N/A 9. A copy of the deed restrictions (if required).
Attached 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County
soil maps are not an acceptable source of soils information.
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Part III. Required Items Checklist, Page 1 of 1
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Wet Basin 1
?S ubcat) Reach Pon Link Drainage Diagram for WetBasinl
Prepared by {enter your company name here}, Printed 11/19/2010
HydroCAD® 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC
WetBasinl Type 1124-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD@ 8.50 s/n 004263 02007 HydroCAD Software Solutions LLC Page 2
Time span=0.00-120.00 hrs, dt=0.04 hrs, 3001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: DA 1 Runoff Area=22.085 ac 20.87% Impervious Runoff Depth=1.26"
Tc=5.0 min CN=79 Runoff=51.15 cfs 2.323 of
Pond 2P: Wet Basin 1 Peak Elev=809.40' Storage=73,317 cf Inflow=51.15 cfs 2.323 of
Primary=0.73 cfs 1.354 of Secondary=0.00 cfs 0.000 of Outflow=0.73 cfs 1.354 of
Total Runoff Area = 22.085 ac Runoff Volume = 2.323 of Average Runoff Depth = 1.26"
79.13% Pervious= 17.475 ac 20.87% Impervious = 4.610 ac
WetBasin1 Type 11 24-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD® 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 1 S: DA 1
Runoff = 51.15 cfs @ 11.96 hrs, Volume= 2.323 af, Depth= 1.26"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-120.00 hrs, dt= 0.04 hrs
Type II 24-hr 1-Year Storm Rainfall=3.10"
Area (ac) CN Description
4.610 98 Paved parking & roofs
17.475 74 >75% Grass cover, Good, HSG C
22.085 79 Weighted Average
17.475 Pervious Area
4.610 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 1S: DA 1
Hydrograph
? Runoff
50- Type II 24-hr 1-Year Storm
45 Rainfall=3.10"
40- Runoff Area=22.085 ac
Runoff Volume=2.323 af
.
35
y Runoff Depth=1.26"
30
Tc=5.0 min
M 25-
CN=79
15 .
10"
5-
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
WetBasin1 Type 11 24-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD® 8.50 s/n 004263 02007 HydroCAD Software Solutions LLC Page 4
Hydrograph for Subcatchment 1 S: DA 1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00
2.00 0.07 0.00 0.00
4.00 0.15 0.00 0.00
6.00 0.25 0.00 0.00
8.00 0.37 0.00 0.00
10.00 0.56 0.00 0.04
12.00 2.06 0.56 45.09
14.00 2.54 0.87 1.79
16.00 2.73 0.99 1.14
18.00 2.86 1.08 0.90
20.00 2.95 1.15 0.66
22.00 3.03 1.21 0.61
24.00 3.10 1.26 0.56
26.00 3.10 1.26 0.00
28.00 3.10 1.26 0.00
30.00 3.10 1.26 0.00
32.00 3.10 1.26 0.00
34.00 3.10 1.26 0.00
36.00 3.10 1.26 0.00
38.00 3.10 1.26 0.00
40.00 3.10 1.26 0.00
42.00 3.10 1.26 0.00
44.00 3.10 1.26 0.00
46.00 3.10 1.26 0.00
48.00 3.10 1.26 0.00
50.00 3.10 1.26 0.00
52.00 3.10 1.26 0.00
54.00 3.10 1.26 0.00
56.00 3.10 1.26 0.00
58.00 3.10 1.26 0.00
60.00 3.10 1.26 0.00
62.00 3.10 1.26 0.00
64.00 3.10 1.26 0.00
66.00 3.10 1.26 0.00
68.00 3.10 1.26 0.00
70.00 3.10 1.26 0.00
72.00 3.10 1.26 0.00
74.00 3.10 1.26 0.00
76.00 3.10 1.26 0.00
78.00 3.10 1.26 0.00
80.00 3.10 1.26 0.00
82.00 3.10 1.26 0.00
84.00 3.10 1.26 0.00
86.00 3.10 1.26 0.00
88.00 3.10 1.26 0.00
90.00 3.10 1.26 0.00
92.00 3.10 1.26 0.00
94.00 3.10 1.26 0.00
96.00 3.10 1.26 0.00
98.00 3.10 1.26 0.00
100.00 3.10 1.26 0.00
102.00 3.10 1.26 0.00
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
104.00 3.10 1.26 0.00
106.00 3.10 1.26 0.00
108.00 3.10 1.26 0.00
110.00 3.10 1.26 0.00
112.00 3.10 1.26 0.00
114.00 3.10 1.26 0.00
116.00 3.10 1.26 0.00
118.00 3.10 1.26 0.00
120.00 3.10 1.26 0.00
WetBasin1 Type 1124-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 02007 HydroCAD Software Solutions LLC Page 5
Summary for Pond 2P: Wet Basin 1
Inflow Area = 22.085 ac, 20.87% Impervious, Inflow Depth = 1.26" for 1-Year Storm event
Inflow = 51.15 cfs @ 11.96 hrs, Volume= 2.323 of
Outflow = 0.73 cfs @ 19.41 hrs, Volume= 1.354 af, Atten= 99%, Lag= 446.7 min
Primary = 0.73 cfs @ 19.41 hrs, Volume= 1.354 of
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.04 hrs / 4
Peak Elev= 809.40'@ 19.41 hrs Surf.Area= 18,773 sf Storage= 73,317 cf
Plug-Flow detention time= 776.0 min calculated for 1.354 of (58% of inflow)
Center-of-Mass det. time= 653.0 min ( 1,496.4 - 843.4 )
Volume Invert Avail.Storage Storage Description
#1 802.50' 106,164 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
802.50 0 0 0
802.90 6,330 1,266 1,266
807.00 10,736 34,985 36,251
807.50 13,053 5,947 42,199
808.00 15,571 7,156 49,355
810.00 20,161 35,732 85,087
810.50 21,046 10,302 95,388
811.00 22,055 10,775 106,164
Device Routing Invert Outlet Devices
#1 Device 3 806.00' 18.0" Vert. Orifice/Grate C= 0.600
#2 Primary 807.50' 4.5" Horiz. Orifice/Grate Limited to weir flow C= 0.600
#3 Primary 809.50' 24.0" Vert. Orifice/Grate C= 0.600
#4 Secondary 809.90' 5.0' long x 20.0' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=0.73 cfs @ 19.41 hrs HW=809.40' (Free Discharge)
L2=Orifice/Grate (Orifice Controls 0.73 cfs @ 6.63 fps)
Orifice/Grate ( Controls 0.00 cfs)
1=Orifice/Grate ( Controls 0.00 cfs)
econdary OutFlow Max=0.00 cfs @ 0.00 hrs HW=802.50' (Free Discharge)
=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
WetBasinl Type 1124-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD(D8.50 s/n 004263 @2007 HydroCAD Software Solutions LLC Page 6
Pond 2P: Wet Basin 1
Hydrograph
¦ Inflow
? Outflow
® Primary
¦ Secondary
N
U
3
O
li
Pond 2P: Wet Basin 1
Stage-Discharge
? Total
Primary
¦ Secondary
m
m
c
O
m
W
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
0 5 10 15 20 25 30 35
Discharge (cfs)
WetBasin1 Type 11 24-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD® 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 7
Pond 2P: Wet Basin 1
Stage-Area-Storage
Surface/Florizontal/Wetted Area (sq-ft)
d
d
c
0
a?
w
100 0 Surface
0 Storage
0 20,000 40,000 60,000 80,000 100,000
Storage (cubic-feet)
WetBasin1 Type 1124-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 8
Hydrograph for Pond 2P: Wet Basin 1
Time Inflow Storage Elevation Outflow Primary Secondary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 802.50 0.00 0.00 0.00
4.00 0.00 0 802.50 0.00 0.00 0.00
8.00 0.00 0 802.50 0.00 0.00 0.00
12.00 45.09 35,081 806.89 0.00 0.00 0.00
16.00 1.14 70,783 809.26 0.71 0.71 0.00
20.00 0.66 73,244 809.39 0.73 0.73 0.00
24.00 0.56 71,602 809.30 0.71 0.71 0.00
28.00 0.00 62,259 808.78 0.60 0.60 0.00
32.00 0.00 54,447 808.32 0.48 0.48 0.00
36.00 0.00 48,434 807.94 0.35 0.35 0.00
40.00 0.00 44,370 807.66 0.20 0.20 0.00
44.00 0.00 42,802 807.55 0.04 0.04 0.00
48.00 0.00 42,456 807.52 0.02 0.02 0.00
52.00 0.00 42,309 807.51 0.01 0.01 0.00
56.00 0.00 42,246 807.50 0.00 0.00 0.00
60.00 0.00 42,219 807.50 0.00 0.00 0.00
64.00 0.00 42,207 807.50 0.00 0.00 0.00
68.00 0.00 42,202 807.50 0.00 0.00 0.00
72.00 0.00 42,200 807.50 0.00 0.00 0.00
76.00 0.00 42,199 807.50 0.00 0.00 0.00
80.00 0.00 42,199 807.50 0.00 0.00 0.00
84.00 0.00 42,199 807.50 0.00 0.00 0.00
88.00 0.00 42,199 807.50 0.00 0.00 0.00
92.00 0.00 42,199 807.50 0.00 0.00 0.00
96.00 0.00 42,199 807.50 0.00 0.00 O.QO
100.00 0.00 42,199 807.50 0.00 0.00 0.00
104.00 0.00 42,199 807.50 0.00 0.00 0.00
108.00 0.00 42,199 807.50 0.00 0.00 0.00
112.00 0.00 42,199 807.50 0.00 0.00 0.00
116.00 0.00 42,199 807.50 0.00 0.00 0.00
120.00 0.00 42,199 807.50 0.00 0.00 0.00
WetBasinl
Type 11 24-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD® 8.50 s/n 004263 02007 HydroCAD Software Solutions LLC Page 9
Stage-Discharge for Pond 2P: Wet Basin 1
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
802.50 0.00 0.00 0.00
802.60 0.00 0.00 0.00
802.70 0.00 0.00 0.00
802.80 0.00 0.00 0.00
802.90 0.00 0.00 0.00
803.00 0.00 0.00 0.00
803.10 0.00 0.00 0.00
803.20 0.00 0.00 0.00
803.30 0.00 0.00 0.00
803.40 0.00 0.00 0.00
803.50 0.00 0.00 0.00
803.60 0.00 0.00 0.00
803.70 0.00 0.00 0.00
803.80 0.00 0.00 0.00
803.90 0.00 0.00 0.00
804.00 0.00 0.00 0.00
804.10 0.00 0.00 0.00
804.20 0.00 0.00 0.00
804.30 0.00 0.00 0.00
804.40 0.00 0.00 0.00
804.50 0.00 0.00 0.00
804.60 0.00 0.00 0.00
804.70 0.00 0.00 0.00
804.80 0.00 0.00 0.00
804.90 0.00 0.00 0.00
805.00 0.00 0.00 0.00
805.10 0.00 0.00 0.00
805.20 0.00 0.00 0.00
805.30 0.00 0.00 0.00
805.40 0.00 0.00 0.00
805.50 0.00 0.00 0.00
805.60 0.00 0.00 0.00
805.70 0.00 0.00 0.00
805.80 0.00 0.00 0.00
805.90 0.00 0.00 0.00
806.00 0.00 0.00 0.00
806.10 0.00 0.00 0.00
806.20 0.00 0.00 0.00
806.30 0.00 0.00 0.00
806.40 0.00 0.00 0.00
806.50 0.00 0.00 0.00
806.60 0.00 0.00 0.00
806.70 0.00 0.00 0.00
806.80 0.00 0.00 0.00
806.90 0.00 0.00 0.00
807.00 0.00 0.00 0.00
807.10 0.00 0.00 0.00
807.20 0.00 0.00 0.00
807.30 0.00 0.00 0.00
807.40 0.00 0.00 0.00
807.50 0.00 0.00 0.00
807.60 0.12 0.12 0.00
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
807.70 0.24 0.24 0.00
807.80 0.29 0.29 0.00
807.90 0.34 0.34 0.00
808.00 0.38 0.38 0.00
808.10 0.41 0.41 0.00
808.20 0.44 0.44 0.00
808.30 0.48 0.48 0.00
808.40 0.50 0.50 0.00
808.50 0.53 0.53 0.00
808.60 0.56 0.56 0.00
808.70 0.58 0.58 0.00
808.80 0.61 0.61 0.00
808.90 0.63 0.63 0.00
809.00 0.65 0.65 0.00
809.10 0.67 0.67 0.00
809.20 0.69 0.69 0.00
809.30 0.71 0.71 0.00
809.40 0.73 0.73 0.00
809.50 0.75 0.75 0.00
809.60 0.83 0.83 0.00
809.70 1.04 1.04 0.00
809.80 1.36 1.36 0.00
809.90 1.79 1.79 0.00
810.00 2.74 2.32 0.42
810.10 4.15 2.95 1.20
810.20 5.88 3.67 2.21
810.30 7.88 4.46 3.42
810.40 10.11 5.33 4.77
810.50 12.54 6.27 6.27
810.60 15.08 7.26 7.82
810.70 17.74 8.29 9.45
810.80 20.61 9.36 11.25
810.90 23.59 10.44 13.15
811.00 26.62 11.42 15.20
811.10 29.12 11.77 17.35
811.20 31.68 12.12 19.57
811.30 34.32 12.45 21.87
811.40 36.98 12.78 24.20
811.50 39.71 13.10 26.61
WetBasin1 Type 11 24-hr 1-Year Storm Rainfall=3.10"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 10
Stage-Area-Storage for Pond 2P: Wet Basin 1
Elevation Surface Storage
(feet) (sq-ft) (cubic-feet)
802.50 0 0
802.60 1,583 79
802.70 3,165 317
802.80 4,747 712
802.90 6,330 1,266
803.00 6,437 1,904
803.10 6,545 2,553
803.20 6,652 3,213
803.30 6,760 3,884
803.40 6,867 4,565
803.50 6,975 5,257
803.60 7,082 5,960
803.70 7,190 6,674
803.80 7,297 7,398
803.90 7,405 8,133
804.00 7,512 8,879
804.10 7,620 9,636
804.20 7,727 10,403
804.30 7,834 11,181
804.40 7,942 11,970
804.50 8,049 12,770
804.60 8,157 13,580
804.70 8,264 14,401
804.80 8,372 15,233
804.90 8,479 16,075
805.00 8,587 16,929
805.10 8,694 17,793
805.20 8,802 18,667
805.30 8,909 19,553
805.40 9,017 20,449
805.50 9,124 21,356
805.60 9,232 22,274
805.70 9,339 23,203
805.80 9,446 24,142
805.90 9,554 25,092
806.00 9,661 26,053
806.10 9,769 27,024
806.20 9,876 28,006
806.30 9,984 28,999
806.40 10,091 30,003
806.50 10,199 31,018
806.60 10,306 32,043
806.70 10,414 33,079
806.80 10,521 34,126
806.90 10,629 35,183
807.00 10,736 36,251
807.10 11,199 37,348
807.20 11,663 38,491
807.30 12,126 39,681
807.40 12,590 40,916
807.50 13,053 42,199
807.60 13,557 43,529
Elevation Surface Storage
(feet) (sq-ft) (cubic-feet)
807.70 14,060 44,910
807.80 14,564 46,341
807.90 15,067 47,823
808.00 15,571 49,355
808.10 15,801 50,923
808.20 16,030 52,515
808.30 16,259 54,129
808.40 16,489 55,767
808.50 16,719 57,427
808.60 16,948 59,110
808.70 17,178 60,817
808.80 17,407 62,546
808.90 17,636 64,298
809.00 17,866 66,073
809.10 18,096 67,871
809.20 18,325 69,692
809.30 18,554 71,536
809.40 18,784 73,403
809.50 19,014 75,293
809.60 19,243 77,206
809.70 19,473 79,142
809.80 19,702 81,100
809.90 19,931 83,082
810.00 20,161 85,087
810.10 20,338 87,112
810.20 20,515 89,154
810.30 20,692 91,214
810.40 20,869 93,293
810.50 21,046 95,388
810.60 21,248 97,503
810.70 21,450 99,638
810.80 21,651 101,793
810.90 21,853 103,968
811.00 22,055 106,164
811.10 22,055 106,164
811.20 22,055 106,164
811.30 22,055 106,164
811.40 22,055 106,164
811.50 22,055 106,164
WetBasinl Type 1124-hr 10-Year Storm Rainfall=5.41 "
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD@ 8.50 s/n 004263 @2007 HydroCAD Software Solutions LLC Page 11
Time span=0.00-120.00 hrs, dt=0.04 hrs, 3001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: DA 1 Runoff Area=22.085 ac 20.87% Impervious Runoff Depth=3.16"
Tc=5.0 min CN=79 Runoff=125.89 cfs 5.812 of
Pond 2P: Wet Basin 1 Peak Elev=811.00' Storage=106,142 cf Inflow=125.89 cfs 5.812 of
Primary=11.41 cfs 3.421 of Secondary=15.18 cfs 1.138 of Outflow=26.59 cfs 4.559 of
Total Runoff Area = 22.085 ac Runoff Volume = 5.812 of Average Runoff Depth = 3.16"
79.13% Pervious= 17.475 ac 20.87% Impervious= 4.610 ac
WetBasin1 Type 1124-hr 10-Year Storm Rainfall=5.41"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 12
Summary for Subcatchment 1 S: DA 1
Runoff = 125.89 cfs @ 11.96 hrs, Volume= 5.812 af, Depth= 3.16"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-120.00 hrs, dt= 0.04 hrs
Type II 24-hr 10-Year Storm Rainfall=5.41"
Area (ac) CN Description
4.610 98 Paved parking & roofs
17.475 74 >75% Grass cover, Good, HSG C
22.085 79 Weighted Average
17.475 Pervious Area
4.610 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 1S: DA 1
Hydrograph
140
Runoff
130 125.89 cfs
120 Type II 24-hr 10=Year Storm
110 _ Rainfall=5.41,.
100 Runoff Area=22.085 ac
90 _ Runoff Volume=5.812 of
80Runoff Depth=3.16'
70 Tc=5.0 min
LL 60 CN=79
50-
40-
30
20
10
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
WetBasinl Type 1124-hr 10-Year Storm Rainfall=5.41"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 13
Hydrograph for Subcatchment 1 S: DA 1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00
2.00 0.12 0.00 0.00
4.00 0.26 0.00 0.00
6.00 0.43 0.00 0.00
8.00 0.65 0.00 0.20
10.00 0.98 0.06 1.21
12.00 3.59 1.63 107.93
14.00 4.44 2.32 3.88
16.00 4.76 2.60 2.41
18.00 4.98 2.79 1.88
20.00 5.15 2.93 1.38
22.00 5.29 3.05 1.26
24.00 5.41 3.16 1.16
26.00 5.41 3.16 0.00
28.00 5.41 3.16 0.00
30.00 5.41 3.16 0.00
32.00 5.41 3.16 0.00
34.00 5.41 3.16 0.00
36.00 5.41 3.16 0.00
38.00 5.41 3.16 0.00
40.00 5.41 3.16 0.00
42.00 5.41 3.16 0.00
44.00 5.41 3.16 0.00
46.00 5.41 3.16 0.00
48.00 5.41 3.16 0.00
50.00 5.41 3.16 0.00
52.00 5.41 3.16 0.00
54.00 5.41 3.16 0.00
56.00 5.41 3.16 0.00
58.00 5.41 3.16 0.00
60.00 5.41 3.16 0.00
62.00 5.41 3.16 0.00
64.00 5.41 3.16 0.00
66.00 5.41 3.16 0.00
68.00 5.41 3.16 0.00
70.00 5.41 3.16 0.00
72.00 5.41 3.16 0.00
74.00 5.41 3.16 0.00
76.00 5.41 3.16 0.00
78.00 5.41 3.16 0.00
80.00 5.41 3.16 0.00
82.00 5.41 3.16 0.00
84.00 5.41 3.16 0.00
86.00 5.41 3.16 0.00
88.00 5.41 3.16 0.00
90.00 5.41 3.16 0.00
92.00 5.41 3.16 0.00
94.00 5.41 3.16 0.00
96.00 5.41 3.16 0.00
98.00 5.41 3.16 0.00
100.00 5.41 3.16 0.00
102.00 5.41 3.16 0.00
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
104.00 5.41 3.16 0.00
106.00 5.41 3.16 0.00
108.00 5.41 3.16 0.00
110.00 5.41 3.16 0.00
112.00 5.41 3.16 0.00
114.00 5.41 3.16 0.00
116.00 5.41 3.16 0.00
118.00 5.41 3.16 0.00
120.00 5.41 3.16 0.00
WetBasin1 Type // 24-hr 10-Year Storm Rainfal1=541"
Prepared by {enter your company name here) Printed 11/19/2010
HydroCAD6 8.50 s/n 004263 @2007 HydroCAD Software Solutions LLC Page 14
Summary for Pond 2P: Wet Basin 1
Inflow Area = 22.085 ac, 20.87% Impervious, Inflow Depth = 3.16" for 10-Year Storm event
Inflow = 125.89 cfs @ 11.96 hrs, Volume= 5.812 of
Outflow = 26.59 cfs @ 12.11 hrs, Volume= 4.559 af, Atten= 79%, Lag= 8.8 min
Primary = 11.41 cfs @ 12.11 hrs, Volume= 3.421 of
Secondary = 15.18 cfs @ 12.11 hrs, Volume= 1.138 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.04 hrs / 4
Peak Elev= 811.00' @ 12.11 hrs Surf.Area= 22,053 sf Storage= 106,142 cf
Plug-Flow detention time= 377.7 min calculated for 4.557 of (78% of inflow)
Center-of-Mass det. time= 292.1 min ( 1,109.1 - 817.0 )
Volume Invert Avail.Storage Storage Description
#1 802.50' 106,164 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
802.50 0 0 0
802.90 6,330 1,266 1,266
807.00 10,736 34,985 36,251
807.50 13,053 5,947 42,199
808.00 15,571 7,156 49,355
810.00 20,161 35,732 85,087
810.50 21,046 10,302 95,388
811.00 22,055 10,775 106,164
Device Routing Invert Outlet Devices
#1 Device 3 806.00' 18.0" Vert. Orifice/Grate C= 0.600
#2 Primary 807.50' 4.5" Horiz. Orifice/Grate Limited to weir flow C= 0.600
#3 Primary 809.50' 24.0" Vert. Orifice/Grate C= 0.600
#4 Secondary 809.90' 5.0' long x 20.0' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=11.40 cfs @ 12.11 hrs HW=810.99' (Free Discharge)
2=Orifice/Grate (Orifice Controls 0.99 cfs @ 9.00 fps)
Orifice/Grate (Passes 10.40 cfs of 10.48 cfs potential flow)
1=Orifice/Grate (Orifice Controls 10.40 cfs @ 5.89 fps)
econdary OutFlow Max=15.09 cfs @ 12.11 hrs HW=810.99' (Free Discharge)
=Broad-Crested Rectangular Weir (Weir Controls 15.09 cfs @ 2.76 fps)
WetBasin1 Type 1124-hr 10-Year Storm Rainfall=5.41 "
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 0 2007 HydroCAD Software Solutions LLC Page 15
Pond 2P: Wet Basin 1
Hydrograph
1
1
1
1
1
N
V
3
O
LL
Pond 2P: Wet Basin 1
Stage-Discharge
m
d
c
0
m
W
¦ Inflow
0 Outflow
0 Primary
¦ Secondary
0 Total
0 Primary
® Secondary
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
0 20 40 60 80 100 120 140
Discharge (cfs)
WetBasin1 Type 11 24-hr 10-Year Storm Rainfall=5.41"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 @2007 HydroCAD Software Solutions LLC Page 16
Pond 2P: Wet Basin 1
Stage-Area-Storage
Surface/HorizontaLYNetted Area (sq-ft)
m
m
c
0
w
w
Q Surface
® Storage
0 20,000 40,000 60,000 80,000 100,000
Storage (cubic-feet)
WetBasin1 Type 1124-hr 10-Year Storm Rainfall=5.41"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 17
Hydrograph for Pond 2P: Wet Basin 1
Time Inflow Storage Elevation Outflow Primary Secondary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 802.50 0.00 0.00 0.00
4.00 0.00 0 802.50 0.00 0.00 0.00
8.00 0.20 341 802.70 0.00 0.00 0.00
12.00 107.93 105,632 810.98 25.92 11.22 14.70
16.00 2.41 85,030 810.00 2.71 2.30 0.41
20.00 1.38 82,356 809.86 1.62 1.62 0.00
24.00 1.16 80,482 809.77 1.25 1.25 0.00
28.00 0.00 69,201 809.17 0.69 0.69 0.00
32.00 0.00 60,118 808.66 0.57 0.57 0.00
36.00 0.00 52,751 808.21 0.45 0.45 0.00
40.00 0.00 47,212 807.86 0.32 0.32 0.00
44.00 0.00 43,706 807.61 0.15 0.15 0.00
48.00 0.00 42,681 807.54 0.03 0.03 0.00
52.00 0.00 42,406 807.52 0.01 0.01 0.00
56.00 0.00 42,288 807.51 0.01 0.01 0.00
60.00 0.00 42,237 807.50 0.00 0.00 0.00
64.00 0.00 42,215 807.50 0.00 0.00 0.00
68.00 0.00 42,206 807.50 0.00 0.00 0.00
72.00 0.00 42,202 807.50 0.00 0.00 0.00
76.00 0.00 42,200 807.50 0.00 0.00 0.00
80.00 0.00 42,199 807.50 0.00 0.00 0.00
84.00 0.00 42,199 807.50 0.00 0.00 0.00
88.00 0.00 42,199 807.50 0.00 0.00 0.00
92.00 0.00 42,199 807.50 0.00 0.00 0.00
96.00 0.00 42,199 807.50 0.00 0.00 0.00
100.00 0.00 42,199 807.50 0.00 0.00 0.00
104.00 0.00 42,199 807.50 0.00 0.00 0.00
108.00 0.00 42,199 807.50 0.00 0.00 0.00
112.00 0.00 42,199 807.50 0.00 0.00 0.00
116.00 0.00 42,199 807.50 0.00 0.00 0.00
120.00 0.00 42,199 807.50 0.00 0.00 0.00
WetBasin1 Type// 24-hr 10-Year Storm Rainfall=5.41"
Prepared by {enter your company name here} Printed 11/19/2010
HydroCAD® 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 18
Stage-Discharge for Pond 2P: Wet Basin 1
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
802.50 0.00 0.00 0.00
802.65 0.00 0.00 0.00
802.80 0.00 0.00 0.00
802.95 0.00 0.00 0.00
803.10 0.00 0.00 0.00
803.25 0.00 0.00 0.00
803.40 0.00 0.00 0.00
803.55 0.00 0.00 0.00
803.70 0.00 0.00 0.00
803.85 0.00 0.00 0.00
804.00 0.00 0.00 0.00
804.15 0.00 0.00 0.00
804.30 0.00 0.00 0.00
804.45 0.00 0.00 0.00
804.60 0.00 0.00 0.00
804.75 0.00 0.00 0.00
804.90 0.00 0.00 0.00
805.05 0.00 0.00 0.00
805.20 0.00 0.00 0.00
805.35 0.00 0.00 0.00
805.50 0.00 0.00 0.00
805.65 0.00 0.00 0.00
805.80 0.00 0.00 0.00
805.95 0.00 0.00 0.00
806.10 0.00 0.00 0.00
806.25 0.00 0.00 0.00
806.40 0.00 0.00 0.00
806.55 0.00 0.00 0.00
806.70 0.00 0.00 0.00
806.85 0.00 0.00 0.00
807.00 0.00 0.00 0.00
807.15 0.00 0.00 0.00
807.30 0.00 0.00 0.00
807.45 0.00 0.00 0.00
807.60 0.12 0.12 0.00
807.75 0.27 0.27 0.00
807.90 0.34 0.34 0.00
808.05 0.39 0.39 0.00
808.20 0.44 0.44 0.00
808.35 0.49 0.49 0.00
808.50 0.53 0.53 0.00
808.65 0.57 0.57 0.00
808.80 0.61 0.61 0.00
808.95 0.64 0.64 0.00
809.10 0.67 0.67 0.00
809.25 0.70 0.70 0.00
809.40 0.73 0.73 0.00
809.55 0.78 0.78 0.00
809.70 1.04 1.04 0.00
809.85 1.56 1.56 0.00
810.00 2.74 2.32 0.42
810.15 4.97 3.30 1.68
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
810.30 7.88 4.46 3.42
810.45 11.30 5.79 5.51
810.60 15.08 7.26 7.82
810.75 19.16 8.82 10.33
810.90 23.59 10.44 13.15
811.05 27.86 11.60 16.26
811.20 31.68 12.12 19.57
811.35 35.64 12.62 23.03
811.50 39.71 13.10 26.61
811.65 44.00 13.56 30.44
811.80 48.45 14.01 34.44
811.95 53.04 14.44 38.60
812.10 57.77 14.86 42.91
812.25 62.64 15.27 47.37
812.40 67.65 15.67 51.98
812.55 72.78 16.05 56.73
812.70 78.05 16.43 61.61
812.85 83.43 16.80 66.63
813.00 88.94 17.17 71.77
813.15 94.57 17.52 77.05
813.30 100.31 17.87 82.44
813.45 106.16 18.21 87.96
813.60 112.13 18.54 93.59
813.75 118.21 18.87 99.34
813.90 124.39 19.19 105.20
814.05 130.68 19.51 111.17
814.20 137.08 19.82 117.25
814.35 143.57 20.13 123.44
814.50 150.17 20.43 129.74
WetBasinl
Type 11 24-hr 10-Year Storm Rainfall=5.41 "
Prepared by {enter your company name here} Printed 11/19/2010
HydroCADO 8.50 s/n 004263 © 2007 HydroCAD Software Solutions LLC Page 19
Stage-Area-Storage for Pond 2P: Wet Basin 1
Elevation Surface Storage
(feet) (sq-ft) (cubic-feet)
802.50 0 0
802.65 2,374 178
802.80 4,747 712
802.95 6,384 1,584
803.10 6,545 2,553
803.25 6,706 3,547
803.40 6,867 4,565
803.55 7,029 5,608
803.70 7,190 6,674
803.85 7,351 7,764
804.00 7,512 8,879
804.15 7,673 10,018
804.30 7,834 11,181
804.45 7,996 12,368
804.60 8,157 13,580
804.75 8,318 14,815
804.90 8,479 16,075
805.05 8,640 17,359
805.20 8,802 18,667
805.35 8,963 20,000
805.50 9,124 21,356
805.65 9,285 22,737
805.80 9,446 24,142
805.95 9,608 25,571
806.10 9,769 27,024
806.25 9,930 28,502
806.40 10,091 30,003
806.55 10,252 31,529
806.70 10,414 33,079
806.85 10,575 34,653
807.00 10,736 36,251
807.15 11,431 37,914
807.30 12,126 39,681
807.45 12,821 41,552
807.60 13,557 43,529
807.75 14,312 45,619
807.90 15,067 47,823
808.05 15,686 50,136
808.20 16,030 52,515
808.35 16,374 54,945
808.50 16,719 57,427
808.65 17,063 59,961
808.80 17,407 62,546
808.95 17,751 65,183
809.10 18,096 67,871
809.25 18,440 70,611
809.40 18,784 73,403
809.55 19,128 76,246
809.70 19,473 79,142
809.85 19,817 82,088
810.00 20,161 85,087
810.15 20,426 88,131
Elevation Surface Storage
(feet) (sq-ft) (cubic-feet)
810.30 20,692 91,214
810.45 20,958 94,338
810.60 21,248 97,503
810.75 21,551 100,713
810.90 21,853 103,968
811.05 22,055 106,164
811.20 22,055 106,164
811.35 22,055 106,164
811.50 22,055 106,164
811.65 22,055 106,164
811.80 22,055 106,164
811.95 22,055 106,164
812.10 22,055 106,164
812.25 22,055 106,164
812.40 22,055 106,164
812.55 22,055 106,164
812.70 22,055 106,164
812.85 22,055 106,164
813.00 22,055 106,164
813.15 22,055 106,164
813.30 22,055 106,164
813.45 22,055 106,164
813.60 22,055 106,164
813.75 22,055 106,164
813.90 22,055 106,164
814.05 22,055 106,164
814.20 22,055 106,164
814.35 22,055 106,164
814.50 22,055 106,164
NaMr Pmenun Green ECMDSVesim43 ? 111/19/2010 i03.25PMCOMPUUTTEDBY. RHH
emmerce Center-Ph.1 --_-?-PR6IECT N0.'. E9.00116 __.._._.?
PRQJECTNAME FouYill,C
FROM STATION/REACH: Ba-1 ,D fAf NRiCZ oaebay NE DRAINADEAREA: 15.5 Aaes DESIGN FREQUENCY: 1 Year Sta.
HYDRAULIC RESULTS
., hek Fbw ebatyllps A- (q It) Hydeu4'I Normal P550 n•0046
I Pmi0d lhrsl Red9OH DeWh BII
25
3.9 9 05 11 19 3.21 03
.39 0 49
S • 04170
30 wietn "= 1
0o u
LINER RESULTS
Not to Scale

Reach 0.1h, T-
IaWyAn*{y V,.I...,
P.miaabk
Cdabled
Solely F-,
Remarks
Stapk Palt.n Phase Ci.. Type Demily Shea Stress
(oal) Shem St,,.
(psq
Soa.4 P550 Vepetalion 3 C Mix 75.95%: 14.00 12 BB 1.09 STABLE
SlapleE Soi F- Sand 3.250 2539 17, STABLE
_Backhlrpil5aem

NORTH AMERICAN GREEN EROSION CONTROL MATERIALS DESIGN SOFTWARE VERSION 4.3
NORTH AMERICAN GREEN CHANNEL PROTECTION - ENGLISH/S.I.
USER SPECIFIED CHANNEL LINING BACK-UP COMPUTATIONS
*****************************************************************************
PROJECT NAME: Foothills Commerce Center - Ph.1 PROJECT NO.: 09.00116
COMPUTED BY: RHH DATE: 11/19/2010
FROM STATION/REACH: Basin 1 TO STATION/REACH: Forebay NE
DRAINAGE AREA: 15.5 Acres DESIGN FREQUENCY: 1-Year Storm
*****************************************************************************
INPUT PARAMETERS
Channel Discharge : 35.9 cfs (1.02 MA 3/s)
Peak Flow Period : 0.5 hours
Channel Slope : 0.417 ft/ft (0.417 m/m)
Channel Bottom Width :5.0 ft (1.52 m)
Left Side Slope :3:1
Right Side Slope :3:1
Channel Lining : P550 Staple E Mix 75-95%
Permi. Shear(Tp) :14.00 psf (670.3 Pa)
Phase = 3
Class = C Vegetation
Soil = Fine Sand
Allowable Soil Shear(Ta):3.25 psf (155.61 Pa)
CALCULATIONS
Initial Depth Estimate = 0.16 * (35.9 /(0.417^0.5))^0.375 = 0.72 ft (.22 m)
Final Channel Depth (after 6 iterations) =.49 ft (0.15 m)
Flow Area = (5.0 * 0.5)+(0.5 *0.49^2 * (3.0+3.0)) = 3.2 sq.ft (0.3 m^2)
Wet Per. =5.0 +(0.5*(((3.OA2)+1)^.5 +((3.0"2)+1)^.5)) = 8.1 ft (2.5 m)
Hydraulic Radius = (3.2 / 8.1) = 0.4 ft (0.1 m)
Channel Velocity =(1.486/0.046)*(0.4^0.667)*(0.417^.5) = 11.2 fps (3.4 m/s)
Channel Effective Manning's Roughness = 0.046
Calculated Shear (Td) = 62.4 * 0.49 * 0.417 = 12.88 psf (616.6 Pa)
Safety Factor = (Tp/Td) _ (14.00 /12.88) = 1.09
Effective Stress on Blanket(Te) = 12.9*(1-0.75)*(/0.046)^2 = 2.54 psf (121.6 Pa)
Safety Factor = (Ta/Te) = (3.25 /2.539) = 1.28
7Jatlt Pmencen Gtean ECMDSVEvicn1.3
PRDJECTNAME: FodHlls Comm>ce Centm Ph.t ?
FROM STATION/REACH: B.-1 OSTAT10N REACH. Fwebar5-
HYDRAULIC RESULTS
Dacheige Peek Fbw eboy it. Aee I, It) Hy= Npimd
I 1 ICfa1 Paiod llxsl ReOtl Depth Bt
9.5 0.5 d 31 2.20 0.30 036
)11/19201003/7PMCOMPUfECBYRHH
PROJECT NO.. 09.00116
DRAINAGE AREA. -41-4.-.. --1DESIGN FREQUENCY: 1-Y-Sl-
P550 (,0 0701
S -02270
30 WiAM1-5.D01t
Not Ip Scale

R each Matting Type
tebAy Analysis VegetdipnCMiapMiivlcs
Pamnsble
Cddrbled
$elety Faclw
Remeiks
Stage Patton 77 777- Dmdy Shea Suess
[pip Sheai 9uevs
Ip+fl
Soapht F550 Vegetation 3 C Mrn 7595: 11.00 512 2.73 $TABtE
StapleE Sd Fbe Sand 3.250 0.395 823 STABLE
B. k to Inpd Sw.,

NORTH AMERICAN GREEN EROSION CONTROL MATERIALS DESIGN SOFTWARE VERSION 4.3
NORTH AMERICAN GREEN CHANNEL PROTECTION - ENGLISH/S.I.
USER SPECIFIED CHANNEL LINING BACK-UP COMPUTATIONS
*****************************************************************************
PROJECT NAME: Foothills Commerce Center - Ph.1 PROJECT NO.: 09.00116
COMPUTED BY: RHH DATE: 11/19/2010
FROM STATION/REACH: Basin 1 TO STATION/REACH: Forebay S
DRAINAGE AREA: 4.1 Acres DESIGN FREQUENCY: 1-Year Storm
*****************************************************************************
INPUT PARAMETERS
*****************************************************************************
Channel Discharge : 9.5 cfs (.27 MA 3/s)
Peak Flow Period : 0.5 hours
Channel Slope : 0.227 ft/ft (0.227 m/m)
Channel Bottom Width : 5.0 ft (1.52 m)
Left Side Slope :3:1
Right Side Slope :3:1
Channel Lining : P550 Staple E Mix 75-95%
Permi. Shear(Tp) :14.00 psf (670.3 Pa)
Phase = 3
Class = C Vegetation
Soil = Fine Sand
Allowable Soil Shear(Ta):3.25 psf (155.61 Pa)

CALCULATIONS
Initial Depth Estimate = 0.16 * (9.5 /(0.227^0.5))^0.375 = 0.49 ft (.15 m)
Final Channel Depth (after 8 iterations) _ .36 ft (0.11 m)
Flow Area = (5.0 * 0.4)+(0.5 *0.36^2 * (3.0+3.0)) = 2.2 sq.ft (0.2 m^2)
Wet Per. =5.0 +(0.4*(((3.0^2)+1)^.5 +((3.0^2)+1)^.5)) = 7.3 ft (2.2 m)
Hydraulic Radius = (2.2 / 7.3) = 0.3 ft (0.1 m)
Channel Velocity =(1.486/0.074)*(0.3^0.667)*(0.227".5) = 4.3 fps (1.3 m/s)
Channel Effective Manning's Roughness = 0.074
Calculated Shear (Td) = 62.4 * 0.36 * 0.227 = 5.12 psf (245.2 Pa)
Safety Factor = (Tp/Td) _ (14.00 /5.12) = 2.73
Effective Stress on Blanket(Te) = 5.1*(1-0.75)*(/0.074)^2 = 0.39 psf (18.9 Pa)
Safety Factor = (Ta/Te) = (3.25 /0.395) = 8.23
@McGM
A S S O C I A T E S
Engineering • Planning Finance
McGill Associates, PA. P.O. Box 2259, Asheville, NC 28802
55 Broad Street, Asheville, NC 28801 828-252-0575 Fax [phone]
PROJECT: _, F }
PROJECT NO.: ra
DESCRIPTION:
CALCULATED BY: F 1?? CHECKED BY:
DATE: nU ?) SHEET NO. , OF I
Pennit Number:
(to be provided by DWQ)
Drainage Area Number:
Wet Detention Basin Operation and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
The wet detention basin system is defined as the wet detention basin,
pretreatment including forebays and the vegetated filter if one is provided
This system (check one):
D does ® does not incorporate a vegetated filter at the outlet.
This system (check one):
D does ® does not incorporate pretreatment other than a forebay.
Important maintenance procedures:
- Immediately after the wet detention basin is established, the plants on the
vegetated shelf and perimeter of the basin should be watered twice weekly if
needed, until the plants become established (commonly six weeks).
- No portion of the wet detention pond should be fertilized after the first initial
fertilization that is required to establish the plants on the vegetated shelf.
- Stable groundcover should be maintained in the drainage area to reduce the
sediment load to the wet detention basin.
- If the basin must be drained for an emergency or to perform maintenance, the
flushing of sediment through the emergency drain should be minimized to the
maximum extent practical.
- Once a year, a dam safety expert should inspect the embankment.
After the wet detention pond is established, it should be inspected once a month and
within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a
Coastal County). Records of operation and maintenance should be kept in a known set
location and must be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: How I will remediate the roblem:
The entire BMP Trash debris is resent. Remove the trash debris.
The perimeter of the wet Areas of bare soil and/or Regrade the soil if necessary to
detention basin erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
egetation is too short or too
F Maintain vegetation at a height of
long. approximately six inches.
Form SW401-Wet Detention Basin O&M-RevA Page 1 of 4
Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element: Potential problem: How I will remediate the problem:
The inlet device: pipe or The pipe is clogged. Unclog the pipe. Dispose of the
swale sediment off-site.
The pipe is cracked or Replace the pipe.
otherwise damaged.
Erosion is occurring in the Regrade the swale if necessary to
swale. smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
The forebay Sediment has accumulated to Search for the source of the
a depth greater than the sediment and remedy the problem if
original design depth for possible. Remove the sediment and
sediment storage. dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Erosion has occurred. Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
prevent future erosion problems.
Weeds are present. Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraying.
The vegetated shelf Best professional practices Prune according to best professional
show that pruning is needed practices
to maintain optimal plant
health.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application to establish the
ground cover if a soil test indicates
it is necessary.
Weeds are present. Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraying.
The main treatment area Sediment has accumulated to Search for the source of the
a depth greater than the sediment and remedy the problem if
original design sediment possible. Remove the sediment and
storage depth. dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Algal growth covers over Consult a professional to remove
50% of the area. and control the algal growth.
Cattails, phragmites or other Remove the plants by wiping them
invasive plants cover 50% of with pesticide (do not spray).
the basin surface.
Form SW401-Wet Detention Basin O&M-Rev.4 Page 2 of 4
Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element: Potential problem: How I will remediate the problem:

The embankment
Shrubs have started to grow _
Remove shrubs immediately.
on the embankment.
Evidence of muskrat or Use traps to remove muskrats and
beaver activity is present consult a professional to remove
beavers.
A tree has started to grow on Consult a dam safety specialist to
the embankment. remove the tree.
An annual inspection by an Make all needed repairs.
appropriate professional
shows that the embankment
needs repair. if applicable)
The outlet device Clogging has occurred. Clean out the outlet device. Dispose
of the sediment off-site.
The outlet device is damaged Repair or replace the outlet device.
The receiving water Erosion or other signs of Contact the local NC Division of
damage have occurred at the Water Quality Regional Office, or
outlet the 401 Oversight Unit at 919-733-
1786.
The measuring device used to determine the sediment elevation shall be such
that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the permanent pool depth reads 4V6 feet in the main pond, the sediment
shall be removed.
When the permanent pool depth reads 4.0 feet in the forebay, the sediment
shall be removed.
BASIN DIAGRAM
( fill in the blanks)
Permanent Pool Elevation 807.5
Sediment Removal
Bottom
803.5- I Pe anen Pool
-------------?-- Volume Sediment Removal Elevation 802.9 Volume
802.5 -ft Min. --------------------------------------------
Sediment Bottom Elevation 801.9 1-ft
Storage Seduner
Storage
FOREBAY MAIN POND
Form SW401-Wet Detention Basin O&M-Rev.4 Page 3 of 4
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project nameToothills Commerce Center
BMP drainage area number:1
Print narne:Brad Cornwell
Title:Public Utilities Director
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
I, 1 J t F?cYY? G1 1 IV' ud yl ?s , a Notary Public for the State of
?A VOII'Qk County of N(T(1J" 0 , do hereby certify that
&Z4o p k, Oem iI L?(_ personally appeared before me this j -7
day of kOTM ? 1' O 10, and acknowledge the due execution of the
forgoing wet detention basin maintenance requirements. Witness my hand and official
seal,
KAREN DILLEMUTH WILKINS
Notary Public, North Carolina
Cleveland County
My Commission Expires
September 21, 2013
SEAL
My commission expires ? j*,W ky a 0/. )
Form SW40I-Wet Detention Basin O&M-Rev.4 Page 4 of 4
Address:P.O. Box 207, 824 West Grover Street, Shelby, North Carolina 28151 (28150)
IBLEINC.
November 16, 2010 BUNNELL-LAMMONS ENGINEERING, INC.
GExEcHwcAL, ENNRONNENTAL AND CONSTRUCTION MATERIALS CONSULTANTS
McGill Associates, P.A.
55 Broad Street
Asheville, North Carolina 28801
Attention: Mr. Dale Pennell, P.E., P.L.S.
Senior Project Manager
Subject: Report of Geotechnical Exploration and
Soil Infiltration Testing
Foothills Commerce Center
Phase I Wet Detention Basins
Shelby, North Carolina
BLE Project No: J10-6667-02
Dear Mr. Pennell:
Bunnell-Lammons Engineering, Incorporated (BLE) is pleased to present the geotechnical exploration
and infiltration test results for the proposed Phase I Wet Detention Basins for the Foothills Commerce
Center project. The geotechnical exploration and infiltration testing was performed generally as
described in BLE Proposal No. P10-0672 dated October 21, 2010. The exploration was authorized by
your signing our Proposal Acceptance Sheet on November 5, 2010.
SITE AND PROJECT DESCRIPTION
We previously prepared a Report of Preliminary Geotechnical Exploration (BLE Project No. J09-
6667-01) dated September 24, 2009. The preliminary report should be read in conjunction with this
report. We have been provided with a drawing titled "Overall Plan" by McGill Associates, P.A. dated
July, 2010 showing the planned development, location of wet detention basins and the existing
topographic contours. The site consists of a 145-acre tract of land generally located within the
southeast quadrant of the intersection of Artee and Plato Lee Roads on the west side of Shelby, North
Carolina (reference Figure 1). We understand that the property is planned to be an industrial business
park. The geotechnical exploration and infiltration testing for this report are specific to the Phase I
Wet Detention Basins, which consists of three basin locations. The basins range' in plan size from
11,926 to 35,628 square feet with maximum depths of 8 to 11 feet.
A north-south trending creek divides the property with approximately % of the property located east of
the creek. The property east of the creek is used as farmland. The remaining '/4 of the site located
west of the creek was formerly a pine forest that was cleared some time ago and has since become
overgrown with brush. The site topography slopes down from the north/northeast to the
south/southwest to Little Beaver Dam Creek and then slopes up to the west to Plato Lee Road. The
ground surface elevations range from about 800 to 880 feet.
105 FAIRvim ROAD, SuIrEA PHONE [phone]
LI I
Report of Geotechnical Exploration and Soil Infiltration Testing November 16, 2010
Foothills Commerce Center - Phase I Wet Detention Basins BLE Project No. J10-6667-02
Shelby, North Carolina
SUBSURFACE EXPLORATION
Ten soil test borings (B-I to B-10) were previously performed as part of the Report of Preliminary
Geotechnical Exploration dated September 24, 2009 (reference Figure 1). Three soil test borings (B-
11 to B-13) were performed specific to the Phase I Wet Detention Basins (reference Figure 2) with a
Soil Sentry truck-mounted drill rig with 2 '/4-inch inside diameter hollow stem augers for the proposed
project. One test boring was drilled near the center of each proposed wet detention basin to depths of
17 to 20 feet. The test boring depth was extended to a minimum of four feet below the proposed
bottom at each wet detention basin. In addition, fourteen infiltration test borings (reference Figure 2)
were drilled within the footprint of the wet detention basins. Three infiltration test borings (I-1 to I-3)
were performed in Basin No. 1, three infiltration test borings (I-4 to I-6) were performed in Basin No.
2 and eight infiltration test borings (I-7 to I-14) were performed in Basin No. 3.
Wet Detention Basin No. 1
Soil Conditions (B-11) - The surface consisted of approximately 5 inches of silty fine sand topsoil.
The subsurface soils generally consisted of loose to firm, moist to wet, slightly micaceous silty fine to
medium sand to a depth of about 4 feet. The loose to firm sand appeared to be alluvial (water
deposited) soils. A chemical odor was noted in the soil sample obtained from 4 %2 to 6 feet. Beneath
the alluvial sand, boring B-11 encountered residual soils that consisted of firm to dense, moist, slightly
micaceous silty fine to medium sand to auger refusal at 18 feet. Residual soils are soils weathered in-
place from the parent rock. Auger refusal likely occurred on partially weathered rock (MR).
Groundwater Conditions - Groundwater was not encountered during the drilling operations.
Groundwater was encountered at a depth of about 5 feet after 4 days. Based on sample coloration, soil
moisture content and observed water levels, the hydrostatic water table was estimated to be at a depth
of approximately 5 feet during the observation period.
Wet Detention Basin No. 2
Soil Conditions (B-12) - The surface consisted of approximately 5 inches of slightly clayey, silty
sandy topsoil. The subsurface soils generally consisted of loose to firm, moist, slightly clayey sandy
silt to moist, silty fine to medium sand to the boring termination depth of 20 feet. This silty fine to
medium sand is residual soil. Residual soils are soils weathered in-place from the parent rock.
Groundwater Conditions - Groundwater was not encountered during the drilling operations or 4
days after the drilling operations. Based on sample coloration, soil moisture content and lack of water,
the hydrostatic water table was estimated to be below the test boring depth of 20 feet.
Wet Detention Basin No. 3
Soil Conditions (B-13) - The surface consisted of approximately 5 inches of slightly clayey, silty
sand topsoil. The subsurface soils generally consisted of loose to firm, moist, slightly micaceous,
slightly clayey, silty fine sand to a depth of about 14 feet. These soils are residual soils which are
weathered in-place from the parent rock. Partially weathered rock or boulders were encountered from
14 to 17 feet. Auger refusal material was encountered at 17 feet.
2
IBLE.
Report of Geotechnical Exploration and Soil Infiltration Testing November 16, 2010
Foothills Commerce Center - Phase I Wet Detention Basins BLE Project No. JI0-6667-02
Shelby, North Carolina
Groundwater Conditions - Groundwater was encountered at a depth of 8 feet during the drilling
operations and at a depth of 6 % feet after 4 days. Based on sample coloration, soil moisture content
and observed water levels, the hydrostatic water table was estimated to be at a depth of 6 '/2 feet during
the observation period.
Groundater Considerations
Groundwater levels may fluctuate several feet with seasonal and rainfall variations and changes in the
water level in adjacent drainage features. Normally, the highest ground-water levels occur in late winter
and spring and the lowest levels occur in late summer and fall. The seasonal high water table (SHWT) is
estimated to exist at a depth of 5 feet in the vicinity of Wet Detention Basins No. 1 and 3 and below a
depth of 20 feet in Wet Detention Basin No. 2.
LABORATORY TESTING
Natural Moisture Content
The natural moisture content of select soil samples was determined in accordance with ASTM D2216.
The moisture content of the soil is the ratio, expressed as a percentage, of the weight of water in a
given mass of soil to the weight of the soil particles. The results are shown on the table below.
Percent Finer than No. 200 Sieve
A percent finer than a No. 200 Sieve test was performed on three soil samples to determine the fines
content of these materials. After initial drying, the sample was washed over a U.S. Standard No. 200
sieve to remove the fines (particles finer than a No. 200 mesh sieve). This test was performed in a
manner similar to that described by ASTM D1140. The results are shown on table 1 below.
TABLE 1- LABORATORY TEST RESULTS
Test
Boring No. Depth
(feet) Natural Moisture
Content (%) Percent Finer than No. 200
Sieve (%) USCS Soil
Classification
B-11 13.5-15.0 12.5 24 SM
B-12 13.5-15.0 26.7 37 SM
B-13 8.5-10.0 38.7 24 SM
INFILTRATION TEST PROCEDURE AND RESULTS
A borehole was drilled and converted to a monitoring well utilizing solid 2-inch diameter PVC casing
to a depth of 2 feet below the proposed pond bottom. The infiltration testing was performed in
general accordance with Appendix C - Testing Requirements for Subsoils for Infiltration, which is a
part of the Stormwater Best Management Practice Design Guide, Volume 2, Vegetative Biofilters
dated September 2004 prepared by the U.S. Environmental Protection Agency.
Upon completion of the infiltration (monitoring) well, and in accordance with the above referenced
testing requirements, the well was then filled with clean water to a depth of 24 inches and allowed to pre-
soak for 24 hours.

Report of Geotechnical Exploration and Soil Infiltration Testing November 16, 2010
Foothills Commerce Center - Phase 1 Wet Detention Basins BLE Project No. J10-6667-02
Shelby, North Carolina
Upon 24 hours later, the casing was refilled with clean water to the top of the casing and the water level
was monitored (measured) from the top of the casing for 1 hour. This test procedure was repeated 3
additional times for a total of four times. The PVC pipe was left in place for additional testing if
required. BLE can remove the PVC pipe and backfill the borehole with soil if no additional testing is
required. The average infiltration rate for each wet detention basin is presented in the following tables.
TABLE 2 - WET DETENTION BASIN NO.1 DWILTRATION TEST RESULTS
Infiltration No. Average Infiltration Rate inches per hour)
I-1 0.31
I-2 1.20
1-3 0.15
Average of I-1 to 1-3 0.55
TABLE 3 - WET DETENTION BASIN NO.2 INFILTRATION TEST RESULTS
Infiltration No. Average Infiltration Rate (inches per hour
I-4 61.73
I-5 86.56
I-6 30.34
Average of I-4 to 1-6 59.54
TABLE 4 - WET DETENTION BASIN NO.3 INFILTRATION TEST RESULTS
Infiltration No. Average Infiltration Rate inches per hour
1-7 0.33
I-8 17.72
I-9 1.92
I-10 0.88
I-11 0.79
1-12 0.79
1-13 1.06
I-14 0.12
Average of I-7 to I-14 3.32
Average w/o high & low Values -8 and I-14 0.96
CONCLUSIONS AND ALTERNATE LINER RECOMAHNDATIONS
The average infiltration test results of 0.55 and 0.96 inch per hour for proposed Basins No. 1 and 3,
respectively are in the range of expected values for firm silty sand residual soil encountered by the test
borings. The infiltration test result of nearly 60 inches per hour for Basin No. 2 is typical for loose sands.
If these infiltration rates are higher than allowable for the basins, a low permeability liner would be
required. Based on the sandy soils encountered by the test borings, a bentonite clay amended liner is
recommended.
4
?
Report of Geotechnical Exploration and Soil Infiltration Testing November 16, 2010
Foothills Commerce Center - Phase I Wet Detention Basins BLE Project No. J10-6667-02
Shelby, North Carolina
The bentonite for a low permeability liner should be free-flowing, powdered, high-swelling, sodium
montmorillonite clay that is free of additives. The bentonite amendment should likely be in the range of
3 to 6 percent by dry weight. The soil used with the bentonite should be a silty sand with 100 percent
passing the No. 4 sieve and a maximum of 35 percent (preferably 25 percent) passing the No. 200 sieve.
The bentonite should be thoroughly mixed with the native soil using a tiller before adding sufficient
water to promote compaction. All fill used for replacement of material that is undercut or liner should be
uniformly compacted in 6-inch lifts to at least 95 percent of the standard Proctor maximum dry density
(ASTM D 698) at 2 to 5 percent above the optimum moisture content of the bentonite soil mixture. We
recommend laboratory tests be performed with samples of the bentonite/soil mixture to confirm the
required bentonite to achieve the required permeability. At the start of construction, a test pad should be
performed at the proposed finished grade within the basin. The test pad should be performed using the
same equipment and construction methods as the actual liner. We recommend that the lift thickness be 8
to 10 inches, loose measure before compaction. Infiltration tests should be performed on the test pad to
verify acceptable permeability rates.
All existing topsoil, vegetation, disturbed soils, and soils containing organic matter or other deleterious
materials should be stripped from within the proposed basins. After stripping and rough excavation
grading, we recommend that areas to provide support for the liner be carefully inspected for soft surficial
soils and proofrolled with a 25-ton, four-wheeled, rubber-tired roller or similar approved equipment. We
recommend a visual inspection rather than proofrolling basin areas that are within 2 feet of the
groundwater level. The proofroller should make at least four passes over each location, with the last two
passes perpendicular to the first two. Any areas which wave, rut, or deflect excessively and continue to
do so after several passes of the proofroller should be excavated to firmer soils. The excavated areas
should be backfilled in thin lifts with suitable compacted fill materials. The proofrolling and excavating
operations should be carefully monitored by an experienced engineering technician working under the
direct supervision of the geotechnical engineer.
We appreciate the opportunity to provide our professional services on this project. If you have any
questions regarding this report, please contact us at [phone].
Sincerely,
BUNNELL-LAMMONS ENGINEERING,
C'ARIr?l
? ??f?? c `????•• •./iii
William T. Gentry III, P.E. = ' ..
• 033927
Senior Engineer ? ••, /.1--16 - P"Z-
NC Registration No. 33927
Gary L. Weekley, P.E.
Senior Geotechnical Engineer
NC Registration No. 8251
Attachments: Figure 1 - Boring Location Plan for Preliminary Geotechnical Exploration
Figure 2 - Boring and Infiltration Location Plan for Phase I Wet Detention Basins
Field Exploration Procedures
Soil Test Boring Logs (3)
Key to Soil Classifications and Consistency Descriptions
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Field Exploration Procedures
Soil Test Borings
The borings were made by mechanically twisting a continuous flight steel auger into the soil. Soil
sampling and penetration testing were performed in general accordance with ASTM D 1586. At
assigned intervals, soil samples were obtained with a standard 1.4-inch I. D., 2-inch O. D., split tube
sampler. The sampler was first seated 6 inches to penetrate any loose cuttings, and then driven an
additional 12 inches with blows of a 140-pound hammer falling 30 inches. The number of hammer
blows required to drive the sampler the final 12 inches was recorded and is designated the "standard
penetration resistance. The penetration resistance, when properly evaluated, is an index to the
strength of the soil and foundation supporting capability.
Representative portions of the soil samples, thus obtained, were placed in glass jars and transported
to the laboratory. In the laboratory, the samples were examined by a geotechnical engineer to verify
the field classifications of the driller. Test Boring Records are attached, showing the soil
descriptions and penetration resistance.
ELMINC SOIL TEST BORING NO. B-11
PROJECT: Foothills Commerce Center Phase I Wet Detention Basins PROJECT NO.: J10-6667-02
CLIENT: McGill Associates DATE START: 10-22-10 END: 10-22-10
BUNNELL-LAIRMONS
E NIMEERNG, INC. LOCATION: Shelby, North Carolina ELEVATION: 812.5
DRILLER: Metro Drill, Inc., R. Frye LOGGED BY: W. Gentry
QE0TECHWCALA0Ew4m0NNDrIAL DRILLING METHOD: Soil Sentry Truck mount; 2-114 inch ID hollow stem auger
CONSULTANTS DEPTH TO - WATER> INITIAL: -y! AFTER 4 DAYS: 1 5 CAVING>
w
ELEVATION/ SOIL DESCRIPTION SOIL
TYPE a STANDARD PENETRATION RESULTS
BLOWSIFOOT
DEPTH (FT) a
rn 2 5 10 20 30 40 50 70 90
5-inches of tan and gray, silty SAND -(topsoil)
Loose, moist, silty, fine to medium SAND - (alluvium) 4

810
Firm, brown, tan, gray and white, wet, slightly micaceous,
:
:
•

:

.
2
silty, fine to medium SAND - (alluvium) 7 ""
5 Chemical odor noted in sample 7

Firm, brown, tan and white, moist, slightly micaceous, silty, 3
6
fine to medium SAND - (residuum) 9 "
805
m to dense, black, brown and tan, moist, slightly
Fir
:
.... 6
micaceous, silty, fine to medium SAND - (residuum) a ""'
®:
10 ........ :.._.._...._....:...:...:..:..:..:..
800
11
,

.
:
;. 16
7 7

15 , . 32
:...:....:..:.._...._....:...:...:
795
Boring terminated at 18 feet due to auger refusal. No
:...:
......
groundwater encountered at time of drilling, but was
........... _..._.
20 encountered at 5 feet after 4 days.
790- a
25 :...:....:..:......:....:...:......:..:.:..
785
30 :... .....:..:..:.... .....:..:...:..:..:. _..
780
i

r
35 :...:....:.. _..:....: ....: .. ....:..:..:.:..
.... :...:.......:.._...._....:......._.
1
775
1
1
SOIL TEST BORING NO. B-11
Sheet 1 of 1
uLMINC SOIL TEST BORING NO. B-12
PROJECT: Foothills Commerce Center Phase I Wet Detention Basins PROJECT NO.: J10-6667-02
13MNELL-4. AIIIAIIIONS CLIENT: McGill Associates DATE START: 10-22-10 END: 10-22-10
ENCsNEERNG9 INC. LOCATION: Shelby, North Carolina ELEVATION: 866.0
GEOTECHWALANDEuvoommemL DRILLER: Metro Drill, Inc., R. Frye LOGGED BY: W. Gentry
CONK LTAMS DRILLING METHOD: Soil Sentry Truck mount; 2-1/4 inch ID hollow stem auger
DEPTH TO - WATER> INITIAL: Q dry AFTER 4 DAYS: 1 dry CAVING> M
ELEVATION/
DEPTH (FT) SOIL DESCRIPTION SOIL i
TYPE i
f STANDARD PENETRATION RESULTS
BLOWSIFOOT
y 2 5 10 20 30 40 50 70 90
5-inches of reddish-brown, slightly clayey, silty SAND - '
_
:
.
.
:
865 (topsoil) 5 ....
....
..
..

Firm, reddish-brown, moist, slightly clayey, fine to medium a ............. f...........
sandy SILT - (residuum)
: . ..
5
7 ; .. ,.:....
10

...._............_.....
...... 7, _.
sso reddish-brown and tan, moist, slightly clayey,
Firm to loose 5
,
fine to medium sandy SILT - (residuum) s - ....... ...........

•: 2
:
.
:. 4
6 .....
...... ..............
_
:...:
_
:
:
:
:
10 .
....
...
...
.......
..
• .. -
855 Loose to firm, tan and white, moist, silty, fine to medium
:
:
SAND - (residuum) : .. ...
.
................. ... _... _...._..
,•:. ,.: 3
4
5

.
15
850
4
.
:.....:...

-.
•. 5 ...
7
7, 7 7
20
845 Boring terminated at 20 feet. No groundwater encountered
at time of drilling.
25
:.....:..
:...:....:..:.._...._ ....:..........
840
:...:....:...:.. _.........:..........:..:.:..
......
30
..
.... :...:....:..... .....:....................
835

i
:..:..:....
.......... :....:..........:....:........
i
35

.
.

? 830
i
:..
.... .
.. ..:..:...........
.....:..............
SOIL TEST BORING NO. B-12
Sheet 1 of 1
ELIBINC SOIL TEST BORING NO. B-13
PROJECT: Foothills Commerce Center Phase I Wet Detention Basins PROJECT NO.: J10-6667-02
BLJNNELA?INIMONS CLIENT: McGill Associates DATE START: 10-22-10 END: 10-22-10
8WNdEERNG,11INIC. LOCATION: Shelby, North Carolina ELEVATION: 807.0
E
A DRILLER: Metro Drill, Inc., R. Frye LOGGED BY: W. Gentry
NvT"MB+w
QE0TEC wAL
ND DRILLING METHOD: Soil Sentry Truck mount; 2-1t4 inch ID hollow stem auger
CONSULTANTS
DEPTH TO - WATER> INITIAL: ?_Z 8 AFTER 4 DAYS- 1 6.5 CAVING> 3W
w
ELEVATION/ SOIL DESCRIPTION SOIL
TYPE Ja STANDARD PENETRATION RESULTS
BLOWSWOOT
DEPTH (FT) Q
y 2 5 10 20 30 40 50 70 90
5-inches of reddish-brown, slightly clayey, silty SAND -
A
ll.

_
:
_
(topsoil) 3 ....
....
...... :...:........ ..
805 Loose to firm, reddish-brown, moist, slightly clayey, silty, :.: :. .:. 3 a...;...... _.......:....._.
fine to medium SAND

.- .. :«

Loose to firm, reddish-brown and black, moist, micaceous, 2
:
:
:
800 silty, fine SAND . :::. 5 ...
...
.
:...:* :..:.._ ....:....
6
s
7 -
10 Trace rock fragments at 10 feet
795- -
22
50/5"
PARTIALLY WEATHERED ROCK which sampled as wet rock 50/5••
15 fragments with silty sand -
:...:....:..:..........._..:...:..:
790
Boring terminated at 17 feet due to auger refusal.
...:....:..:
......
Groundwater encountered at 8 feet at time of drilling and at
6.5 feet after 4 days.
.
.
:
:
_
_
:
;
20 ...
..
..
..
....
....
..
785 . ..:...:....:..:..:........:.................
25 :...:....:.._..:....:...._ ..:...:..:..:....
780
:.._..:..
...... :...:....................:...........
30 7' 7, .............:...:..:......
? 775 ...... :...:....:..:.. .....:....:... .......:..:..:..

a .......... :....:......... ......:.......... .......
35 :....:......:............:...:.
770 :........................
7, 7,
i
SOIL TEST BORING NO. B-13
3 Sheet 1 of 1

IBLE..
KEY TO SOIL CLASSIFICATIONS AND CONSISTENCY DESCRIPTIONS
BUNNELL-LAMMONS ENGINEERING, INC.
ASHEVILLE, NORTH CAROLINA
Penetration Resistance* Relative Particle Size Identification
Blows per Foot Density Balder. Greater than 300 mm
SANDS Cobble: 75 to 300 mm
0 to 4 Very Loose
loose Gravel:
Coarse -19 to 75 mm
5 to 10
11 to 20 Firm Fine - 4.75 to 19 mm
21 to 30 Very Firm
Dense Sand:
Coarse - 2 to 4.75 mm
31 to 50
over So Very Dense Medium - 0.425 to 2 mm
Fine - 0.075 to 0.425 mm
Silt & Clay: Less than 0.075 mm
Penetration Resistance* Consistency
Blows per Foot
SILTS and CLAYS
0 to 2 Very Soft
ft

12 Number of blows in first 6 inches
3 to 4 Firm 15 Number of blows in second 8-inches
5 to 8 Stiff 18 Number of blows in third 6-inches
9 to 15
16 to 30 very Stiff
31 to 50 Hard
over 50 Very Hard
*ASTM D 1586
® Grab Sample
Split Spoon Sample
®
® Undistrurbed Sample
•
Well-graded Gravel
GW
0
a Q0 Poorly-graded Gravel
O o GP
KEY TO DRILLING SYMBOLS
_RL Groundwater Table at Time of Drilling
A Groundwater Table 24 Hours after Completion of Drilling
KEY TO SOIL CLASSIFICATIONS
Low Plasticity Clay
CL
Sandy Clay
CLS
Clayey Silt SM Sand
MH
Sandy Silt Topsail
MLS e> TOPSOIL
5acm
15,911111111 Partially Weathered Rock Silty Clay Sand Bedrock
BLDi2CBBL CL-ML SW BEDROCK
High Plasticity Clay Silt
CH ML
Clayey
Sand Concrete
SC A5
M E_4rL_<