SW6080804_Calculations_20081002

1 S A A C S'
CIVIL ENGINEERING DESIGN & LAND SURVEYING
8720 RED OAK BOULEVARD, STE, 420
CHARLOTTE, N.C. 28217
PHONE [phone] FAX [phone]
h�. � r ,I �; •�' a Ll 4:>
116 Fayetteville Hwy
Raeford, North Carolina
OCT 0 2 2008
Project Calculations
9/10/2008
vfil'?��fl'e
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Project Summary
The project site is located in the City of Raeford a the corner of Fayetteville Hwy and W.
Edinborough Street. The existing site is currently a gas/service station. The site will be
completely demolished and a new 3,600 S.F. Bojangles Restaurant will be constructed at the site.
The existing and proposed site drains to 3 outlet points: Two NCDOT storm systems at the
northwest corner of the site and the south west comer of the site and the final outlet point is a
swale running along W.Edinborogh Street at the northeast corner of the site.
Per NCDENR, Hoke county is a "tipped" county and therefore, under the Phase II NPDES
permitting requirements. The existing site consists of 24,350 S.F. of impervious area and the
Proposed site consists of 33,193 S.F. of impervious area, therefore, per NCDENR requirements a
Water Quality Measure (Bio-retention Cell) was designed to treat a minimum of the 8,843 S.F.
difference between existing and proposed impervious.
The treated impervious drains to the northwest corner of the site into the NCDOT storm drain
system. Peak flows for the Pre -developed area entering the northwest storm drain system were
determined to be 0.80 cfs at a peak concentration time of 5 minutes.
Peak flows for the Post -Developed Area entering the Bioretention Cell were determined to be
1.25 cfs at a concentration time of 5 minutes. The capacity of the two 6" underdrain pipes
designed for the Bioretention Cell is approximately 0.4 cfs per pipe, therefore, meeting the pre -
developed peak flow requirement.

I YEAR - 24 HOUR (PEAK FLOW
CALCULATIONS

BOJANGLES - RAEFORD NC
I. 1 year - 24 hour Storm Calculations
Refer Storm Drainage Area Exhibit Map
Rational Method used for pipe sizing.
A time of concentration of 5 minutes has been assumed in
determining a rainfall intensity of 5.23 (in/hr) for the 1 year 24 hour design storm.
Based on Rainfall curves from the NOAA's National Weather Service.
PRE -DEVELOPED AREA
(assumes developed conditions)
A=
0.205
acres
1=1
5.23
in/hour
C=1
0.745
Q = (C)(1)(A) _
1.80
cfs
POST -DEVELOPED TREATED AREA
A=
0.304
acres
1=
5.23
in/hour
C=
0.784
Q
.
1.25
cfs
Q (total)=
.8 cfs
0.50%.=
Capacity of 6" Underdrain Pipe
6
" HDPE @
.43
<
.8 cfs
PROPOSED SWALE 1
A=
0.043
acres
1=
5.23
in/hour
C=
0.720
Q = (C)(1)(A) _
.16
cfs
PROPOSED SWALE 2
A=
0.125
acres
1=
5.23
in/hour
C=
0.820
Q
.54
cfs
P:\1 - PROJECTS\Boianales\Raeford-08049\Enaineerino\Calculations\08049-STORM.xls

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Precipitation Frequency Data Server
Page 1 of 4
' POINT PRECIPITATION'
FREQUENCY ESTIMATES ;, e
FROM NOAA ATLAS 14 ��h1"4in nrs��
North Carolina 35 N 79.22 W 242 feet
from "Precipitation -Frequency Atlas of the United States' NOAA Atlas 14, Volume 2, Version 3
G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley
NOAA, National Weather Service, Silver Spring, Maryland, 2004
Extracted: Tire Aug 12 2008
Confidence Limits Seasonality ,Location Maps ,� Other Info..' GIS,data., ,Maps
Precipitation Intensity Estimates (in/hr)
ARI *
5 mm
10
-
IS
30
60
-
120
-
3 hr
6 hr
12
24
48
4
7
❑❑❑❑
10
20
30
45
-
60
-
(years)
min
mm
mm
mm
mm
hr
Ilr
lir
day
day
day
day
day
clay
day
1�
5.23
4.18
3.48
2.39
1.49
0.87
0.61
0.37
0.21
0.13
0.07
0.04
0.03
0.02
0.01
FO 011
0.01
0.01
n
6.17
4.94
4.14
2.86
1.79
1.05
0.74
0.4
O0.26
0.15
0.09
0.05
0.03
0.03
0.02
0.01
0.01
0.01
0
7.20
5.77
4.86 .
3.45
2.21
1.32
0.94
0.56
0.33
0.19
0.11
0.06
0.04
0.03
0.02
0.02
0.01
0.01
10
7.97
6.38
5.38
3.90
2.54
1.53
1.09
0.65
0.39
0.23
0.13
0.07
0.05
0.04
0.02
0.02
0.02
0.01
25
8.89
7.09
5.99
4.44
2.95
1.81
1.31
0.79
0.47
0.27
0.15
0.08
0.05
0.04
0.03
0.02
0.02
0.02
50
9.56
7.61
6.43
4.84
3.28
2.03
1.48
0.89
0.54
0.31
0.17
0.10
0.06
0.05
0.03
0.02
0.02
0.02
100
10.20
8.1 ]
6.83
5.23
3.60
2.25
1.66
1.01
0.61
0.34
0.19
0.11
0.07
0.05
0.03
E3]Efl
0.02
200
]0.80
8.56
7.20
5.60
3.93
2.48
1-
1.13
0.68
0.38
0.22
0.12
0.07
0.06
0.04
0.03
0.02
0.02
500
11.53
9.13
7.66
6.09
4.37
-
2.12
1.30
0.79
0.44
0.25
0.13
OF087
0.06
0.04
0.03
0.02
0.02
1000
12.11
9.53
7.98.6.46
4.71
3.04
2.34
1.43
0.89
0.48
0.27
0.14
0.09
0.07
0.04
0.03
0.02
0.02
* These precipitation frequency estimates are based on a partial duration series ARI is the Average Recurrence Interval
Please refer to the documentation for more information. NOTE: Formatting forces estimates near zero to appear as zero
* F- Upper bound of the 90% confidence interval
Precipitation Intensity Estimates in/hr
ARI** 5 10 15 30 60 120 3 6 12 24 48 4 7 ]0 20 30 45 60
(years) min min min min min min hr hr hr hr hr day day day day day dayI day
1�
5.78
4.61
3.85
2.64
1.64
0.97
0.69
0.41
0.24
0.14
0.08
0.04
0.03
0.02
0.02
0.01
0.01
0.0]
n6.83
5.45
4.57
3.16
1.98
L18
0.83
0.49
0.29
0.17
0.10
0.05
0.04
0.03
0.02
0.02
0.01
0.01
F5
7.9
66.37
5.38
3.82
2.45
1.48
1.05
0.62
0.37
0.21
0.12
0.07
0.04
0.03
0.02
0.02 IF
01
0.01
]0
8.80
7.03
5.93
4.29
2.80
1.71
1.22
0.72
0.43
0.24
0.14
0.08
0.05
0.04
0.02
0.02
0.02
0.01
25
9.78
7.80
6.59
4.88
3.25
2.02
1.46
0.87
0.52
0.29
0.17
0.09
0.06
0.04
0.03
0.02
0.02
0.02
50
]0.50
8.36
7.06
5.32
3.60
2.26
1.65
0.99
0.59
0.33
0.19
0.10
0.07
0.05
0.03
0.02
0.02
0.02
100
11.20
8.89
7.50
5.74
3.95
2.51
1.85
1.11
0.67
0.37
0.21
0.11
0.07
0.05
0.03
0.03
0.02
0.02
200
11.84
9.39
7.90
6.15
4.31
2.77
2.07
1.24
0.75
0.41
0.23
0.13
0.08
0.06
0.04
0.03
0.02
0.02
500
12.66
10.01
8.40
6.68
4.79
3.11
2.37
1.43
0.87
0.47
0.26
0.14
0.09
0.07
0.04
0.03
0.02
0.02
1000
13.30.
]0.46
8.76
7.09
5.18
3.39
2.61
1.58
0.97
0.52
0.29
0.15
0.10
0.07
0.04
0.03
0.03
0.02
' I he upper bound of the confidence Interval at g0%confidence level is the value which o"/o of the simulated quanble values for a given frequency are greater man.
These precipitation frequency estimates are based on a partial duration series. ARI is the Average Recurrence Interval.
Please refer to the documentation for more information. NOTE: Formatting prevents estimates near zero to appear as zero.
* Lower bound of the 90% confidence interval
Precipitation Intensity Estimates in/hr)
ARI** 5 10 15 30 60 120 3 6 12 24 48 4 7 io 20 30 45 60
(years) min min min min min min hr 11 hr hr hr day day day 11 day 11 day 11 day Iday
1= 4.76 3.80 3.17 2.17 1.35 0.78 0.55 0.33 0.19 0.12 0.07 0.04 0.03 0.02 0.01 0.01 0.01 0.01
=5.63 4.50 3.77 2.60 1.63 0.95 0.67 0.40 0.2E 0.14 0.08 0.05 0.03 0.02 0.02 0.01 0.01 0.01
ininnnnnnnnnnnnnnnnnn
http://hdsc.nws.n6aa.gov/cgi-bin/Irdsclbui ldout.perl?type=idf&units=us&series=pd&statename=NORTH+C... 8/12/2008

Precipitation Frequency Data Server
Page 1 of 4
POINT PRECIPITATION',
r2 a
FREQUENCY ESTIMATES:
FROM NOAA ATLAS 14 „....A°
North Carolina 35 N 79.22 W 242 feet
from "Precipitation -Frequency Atlas of the United States" NOAA Atlas 14, Volume 2, Version 3
G.M. Bonnin, D. Martin, B. Lin, T. Parzybuk, M. Yekla, and D. Riley
NOAA, National Weather Service, Silver Spring, Maryland, 2004
Extracted: Mon Aug 11 2008
Other Info. II GIS data
Estimates
ARI*
(Years)
5
min
10
min
15
tpm
❑❑❑�
30
mm
60
m1n
120
3 hr
6 hr
12 hr
24 hr
48 hr
4 day_
7 day
10
tlay
❑�❑
20
rlay
30
rlax
45
ra y
60
clay
mm
=1
0.44
0.70
0.87
1.19
1.49
1.74
1.84
2.19
2.58
3.04
3.53
3.97
4.61
5.28
Z I l
8.84
11.18
13.38
n
0.51
0.82
1.03
1.43
1.79
2.10
2.23
2.65
3.13
3.68
4.26
4.77
5.51
6.30
8.43
10.43
13.13
15.68
0
0.60
0.96
1.22
1.73
2.21
2.64
2.81
3.35
3.97
4.66
5.35
5.93
6.77
7.62
10.02
12.19
I5.11
17.87
10
0.66
1.06
1.34
1.95
2.54
3.06
3.28
3.92
4.66
5.44
6.22
6.85
7.76
8.64
11.28
13.56
16.62
19.53
25
0.74
1.18
1.50
2.22
2.95
3.62
3.92
4.70
5.64
6.52
7.42
8.12
9.13
10.03
12.96
15.35
18.- 5 7
21.67
50
0.80
1.27
1.61
2.42
3.28
4.06
4.45
5.35
G.45
7.38
8.37
9.13
10.22
11.13
14.28
16.73
20.05
23.28
100
0.85
F 3-51
1.71
2.62
3.60
4.51
4.99
6.03
7.31
8.27
9.36
10.17
11.34
12.23
15.61
18.10
21.50
24.84
200
0.90
1.43
1.80
2.80
3.93
4.97
5.57
6.74
8.24
9.19
10.38
11.25
12.49
13.36
16.96
19.46
22.92
26.36
500
0.96
1.52
1.9]
3.05
4.37
5.59
6.3
.769.578 7
10.46
11.78
12.72
14.07
14.88
18.79
21.29
24.79
28.34
1000
1.01
1.59
1.99
LE
4.71
KE
7.04
Kfl
10.67
] 1.47
12.88
I3.88
15.32
16.06
20.21
22.69
26.20
29.82
These precipitation frequency estimates are based on a partial duration series ARI is the Average Recurrence Interval.
Please refer to the documentation for more information. NOTE: Formatting forces estimates near zero to appear as zero.
* Upper bound of the 90% confidence interval
Precipitation Frequency Estimates (inches)
ARI** ❑5 10 15 30 60 120 3❑❑1 12 hr 48 ❑4 ❑7 10 20 30 45 60
(years) mm mm mm mm mm mm hr hr hr hr Iv day day day day day day day
1�
0.48
0.77
0.96
1.32
1.64
1.95
2.06
2.44
2.88
3.29
3.80
4.24
4.92
5.61
7.54
9.35
11.80
14.09
�2
0.57
0.91
1.14
1.58
].98
2.35
2.50
2.95
3.48
3.98
4.58
5.09
5.89
6.69
8.94
11.03
13.86
16.49
5
0.66
1.06
1.34
1.91
2.45
2.95
3.15
3.72
4.42
5.04
5.76
6.33
7.24
8.08
10.63
12.89
15.95
18.79
10
0.73
1.17
1.48
2.15
2.80
3.41
3.67
4.34
5.18
5.88
6.69
7.30
8.30
9.18
11.95
]4.33
17.54
20.54
25
0.81
1.30
1.65
2.44
3.25
F 04JEflEN]KN]EW]n7j
8.66
9.75
10.65
13.74
16.23
19. 00
22.78
50
0.88
1.39
1.76
2.66
3.60
4.53
4.97
5.9]
7.13
7.96
8.99
9.73
10.92
11.81
15.14
17.71
21.18
24.48
100
0.93
1.48
1.87
2.87
3.95
5.03
5.57
6.64
8.06
8.92
10.06
10.85
12.13
12. 99
16.56
19.17
22.71
26.15
200
0.99
1.56
1.97
3A7
4.31
5.53
6.20
Z42
9.08
9.91
I1.16
12. 11
13.37
14.20
18.01
20.64
24.25
27.77
500
1.05
].67
2.10
3.34
4.79
6.22
7.10
8.53
10.54
11.28
12.68
13.60
15.09
15.84
19.98
22.61
26.27
29.92
1000
1.11
1.74
2.19
3.55
S. ] 8
6.78
7.83
9.44
11.73
12.38
13.89
14.86
16.44
17.12
21.52
24.15
27.81
31.54
"The upper bound of the confidence interval at 90% confidence level is the value which 5%of the simulated quanfile values for a given frequency are greater than.
These precipitation frequency estimates are based on a oadial duration series ARI is the Average Recurrence Interval.
Please refer to the documentation for more informaton. NOTE: Formatting prevents estimates near zero to appear as zero.
* Lower bound of the 90% confidence interval
Precipitation Frequency Estimates (inches)
ARI** 5 10 15 30 60 120 3 6 12 24 48 4 7 10 20 30 45 60
(years) min min min min min min hr hr lu hr hr day day day day day day day
0.40 0.63 0.79 1.09 1.35 1.57 L66 1.99 2.33 2.82 3.29 3.72 4.31 4.97 6.72 8.37 10.60 ]2.72
0.47 0.75 0.94 1.30 L63 1.90 2.01 2.41 2.83 3.41 . 3.97 4.47 5.16 5.93 7.96 9.87 I2.44 14.89
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http://hdsc.nws.noaa.gov/cgi-bin/hdscibuildout.perl?type=pf&units=us&series=pd&statename=NORTH+C... 8/11 /2008

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W AVENUE
o Q E P 5C PUBLIC R/ (APPARENT)
97.0
y
{ I } •9� I // /�---_--- 4­ -498.p
PROP SWALE 1
OTtL EA = 1,882 S.F./O. 3
A.C.
Do —
I
/•"" `•{ I BOJANGLE'S `\\
3,566 S.F. 09�\\
i !' 4 1 S.F.=0.0918 A.C. 0.
/ 9 2 S.F.=0.2264 A.C. IM
I 13, 3 S.F.=0.3183 TOTAL
' l ITO RAINGARDEN
1 �w.
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TgTA AREA = 5,463 S.F./O.1
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/-__-_--__-__
I
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JOSEPHINE FLOWERS
TAX #694240801063
00
DEED BK 222, PG 546
I/
POST -DEVELOPED
BIORETENTION DRAINAGE
AREA MAP
SCALE: 1 `30'
MARILYN E. SMITH
TAX #694240801062
DEED BK 595, PG 285
CHARLES E. GREEN
TAX #694240801061
DEED BK 472. PG 822

Proposed Swale 1
Worksheet for Trapezoidal Channel
Project File
p:\1 - projects\bojangles\raeford-08049\engineering\calculations\08049.fm2
Worksheet
08049-SWALE1
Flow Element
Trapezoidal Channel
Method
Manning's Formula
Solve For
Channel Depth
Input Data
Mannings Coefficient
0.030
Channel Slope
0.010000
ft/ft
Left Side Slope
17.000000
H : V
Right Side Slope
17.000000
H : V
Bottom Width
1.00
ft
Discharge
0.16
cfs
Results
Depth
0.09
ft
Flow Area
0.22
ft'
Wetted Perimeter
4.02
ft
Top Width
4.02
ft
Critical Depth
0.06
ft
Critical Slope
0.037602 ft/ft
Velocity
0.72
ft/s
Velocity Head
0.01
ft
Specific Energy
0.10
ft
Froude Number
0.54
Flow is subcritical.
09/08/08 FlowMaster v5.13
04:08:14 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1

Cross Section
Cross Section for Trapezoidal Channel
Project Description
Project File
p:\1 - projects\bojangles\raeford-08049\engineering\calculations\08049.fm2
Worksheet
08049-SWALE1
Flow Element
Trapezoidal Channel
Method
Manning's Formula
Solve For
Channel Depth
Section Data
Mannings Coefficient
0.030
Channel Slope
0.010000
ft/ft
Depth
0.09
ft
Left Side Slope
17.000000
H : V
Right Side Slope
17.000000
H : V
Bottom Width
1.00
ft
Discharge
0.16
cfs
1.00 ft
ft
1
V
H 1.0
NITS
09/08/08
04:07:56 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone]
FlowMasler v5.13
Page 1 of 1

PROPOSED SWALE 2
Worksheet for Trapezoidal Channel
Project Description
Project File
p:\1 - projects\bojangles\raeford-08049\engineering\calculations\08049.fm2
Worksheet
08049-SWALE2
Flow Element
Trapezoidal Channel
Method
Mannino's Formula
Input Data
Mannings Coefficient
0.030
Channel Slope
0.010000 ft/ft
Left Side Slope
16.000000 H : V
Right Side Slope
16.000000 H : V
Bottom Width
1.00 ft
Discharge
0.54 cfs
Results
Depth
0.16
ft
Flow Area
0.54
ft2
Wetted Perimeter
5.98
ft
Top Width
5.97
ft
Critical Depth
0.12
ft
Critical Slope
0.031487
ft/ft
Velocity
1.00
ft/s
Velocity Head
0.02
ft
Specific Energy
0.17
ft
Froude Number
0.58
Flow is subcritical.
09/08/08 I FlowMaster v5.13
04:05:55 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1

PROPOSED SWALE 2
Cross Section for Trapezoidal Channel
Project File
p:\1 - projects\bojangles\raeford-08049\engineering\calculations\08049.fm2
Worksheet
08049-SWALE2
Flow Element
Trapezoidal Channel
Method
Manning's Formula
Solve For
Channel Depth
Section Data
Mannings Coefficient
0.030
Channel Slope
0.010000
ft/ft
Depth
0.16
ft
Left Side Slope
16.000000
H : V
Right Side Slope
16.000000
H : V
Bottom Width
1.00
ft
Discharge
0.54
cfs
0.16 ft
�—.
1.00 ft
1
V
H 1.0
NTS
09/08/08 FlowMaster v5.13
04*01*56 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1

B"IORETENTI®N CELL
CALCULATIONS

1.]10]V 2111ii=IIY9lei 090011flgWTV111M 061
BMP Drainage Information
Drainage Facility No.:
1
Total Drainage Area, AD (Ac.) =
0.32
See Drainage Area Exhibit
Impervious Area (Ac.) =
0.23
Total Proposed Impervious Area
Percent Impervious Area, Iq =
71.2
SCS Curve Number, CN =
81
(Hydrologic Group A Soil)
Time of Concentration, t, =
N/A
See Computer Output
Stage -Storage Information:
Top of Filter Media =
499.75
Elevation
Surface Area (fit')
Incremental Volume (ft')
Cumulative
Volume (ft)
Cumulative
Volume (ac-ft)
499.75
838
0
0
0.0000
500.50
1267
789
789
0.0181
501.00
1571
710
1,499
0.0344
Compute Water Quality Volume (WQ„) - Schueler Method
Runoff Coefficient, R, =
0.6908
= 0.05 + 0.0090q)
Water Quality Volume, WQv (acre-feet) =
0.0183
= 1.OR,Ad12
Water Quality Volume, WQ, (ft) =
797.37
= (43,560)(1.0)R,Ap/12
Additional WQv of 18% =
940.89
= WQv' 1.18
Water Quality Storage Elevation =
500.6
Less than or equal to 1' of depth :. O.K.
Min. Surface Area Allowed @ WQ Storage Elevation =
1254.52
= (WQ, ft) / (WQ depth)
Surface Area Provided @ WQ Storage Elevation =
1332.00
Compute Soil Media Surface Area
Depth of sand filter bed, dr (ft) = 2 = minimum depth of 1.5 ft (Per NCDENR BMP Manual)
Coefficient of permeability for sand filter bed, k (ft/day) = 2 = 1 inch/hour
Time to drain WQ, through sand filter, tf (day) = 1.428 = (df + Ponding Depth)/k
Average head, hr (it) = 0.43 = 1/2' WQ, Storage Depth
Required Surface Area for Sand Filter Bed, Ar (ft) = 271.23 = (WQ,)(dr)/(k)(tr)(hf + dr) Darcy's Equation
Provided Surface Area for Sand Filter Bed, Ar (ft') = 837.51
Staae-Discharae for Soil Media
Ar=(WQ,)(dr)/[(k)(tr)(hr+dr)] Darcy's Equation
(WQj/(A) = Q. = (%M)(k)(hr + dr)/(dd
Aq = provided surface area of filter bed (ft)
dr= filter bed depth (ft)
k = coefficient of permeability of filter media (ft/day)
hr = average height of water above filter bed (ft)
Elevation
hr (ft)
Q. (cf/day)
Qo (cfs)
10*% (cfs)
499.75
0.00
0
0,0000
0.0000
500.00
0.25
1,884
0.0218
0.2181
500.25
0.50
2,094
0.0242
0.2423
500.50
0.75
2,303
0.0267
0.2666
500.75
1.00
2,513
0,0291
0.2908
501.00
1.25
2,722
0.0315
0,3150
P:\1 - PROJECTS\Bojangles\Raeford-08049\Engineering\Calculations\08049-RAIN GARDEN.xls

Design Underdrain System:
The underdrain pipes are designed to carry approximately 10 times the maximum flow exfltrating from the sand filter media.
This maximum flow (10' Qa) is computed from Darcy's law and assumes maximum ponding and complete saturation
along the depth of the filter medium.
Emergency Spillway Elevation =
Top of Media Filter Elevation =
Max. height of water above filter bed, hmax (ft)
Qo max @ avg. head above top of sand filler media (cfs) _
Roughness factor, n =
Internal Slope, S =
Diameter of single pipe, D (inches) _
500.6
499.75
0.86
0.2354
1/2 hmax
0.012
0.005
(0.5%min.)
4.783
Manning's Equation: D = [((Qa ma: ayS"0.5)]^0.3751*16
Minimum allowable pipe diameter is 4 inches. A minimum of two pipes should be installed for redundancy.
Bioretention Design Elements
Bottom of Pond Elevation:
499.75
Ponding Depth (ft):
0.86 (9" min. - 12" max. Recommended)
Outlet Structure Grate Elevation:
500.6
Top of Berm Elevation:
501.1
Depth of sand Mixture (fit):
2.00
Depth of Stone Bed (inches):
8.00
P:\1 - PROJECTS\Bojangles\Raeford-08049\Engineering\Calculations\08049-RAIN GARDEN.xls

GE®TECHNICAL

1
I
REPORT OF SUBSURFACE EXPLORATION
1 PROPOSED BOJANGLES' RESTAURANT
RAEFORD, NORTH CAROLINA
S&ML Project No. 1351-08-132
I
I
Prepared for:
Bojangles' Restaurants, Inc.
9432 Southern Pine Blvd.
Charlotte, North Carolina 28273
Prepared C
Imm
*S&MUM
1' Chicago Drive # 116
July 9, 2008

ir �f, a,
16,
Y
July 9, 2008
Bojangles' Restaurants, Inc.
9432 Southern Pine Blvd.
Charlotte, North Carolina 28273
Attention: Mr. Claude Clark
Reference: Report of Subsurface Exploration
Proposed Bojangles' Restaurant
Raeford, North Carolina
S&ME Project No. 1351-08-132
Dear Mr. Clark:
S&ME, Inc. is pleased to submit this report of the subsurface exploration for the
proposed Bojangles' restaurant building in Raeford, North Carolina. Our exploration was
performed in general accordance with our Master Services Agreement for Geotechnical
and Environmental Services proposal No. 1351-18440-07, dated August 27, 2007. The
purpose of this exploration was to explore general subsurface conditions at the site and
evaluate those conditions with regard to site preparation and foundation support for the
new construction. This report presents a summary of pertinent project information,
results of our field testing, and our geotechnical recommendations and conclusions.
Authorization to proceed with this report was provided through your execution of our
Master Services Agreement for Geotechnical and Environmental Services which was
incorporated into our proposal.
S&ME, Inc. appreciates this opportunity to be of service to you. Please call if you have
questions concerning this report or any of our services.
Respectfully submitted,
S&ME Inc.
01
q! �QoFESSIOiy9 =
..
3pA66�-i? 8
! Brian C. McKean, R.E.'..
_i Branch Manager = B•..FNoiNE.:
NC Registration No p,M°�
Kristen Hill, P.E.
Senior Engineer
A-&
1
SWE, INC. / 409 Chicago Drive, Suite 116 / Fayetteville, INC 28306 / p 910.323.1091 f 910.323.3499 / v .smeinc.com

Report of Subsurface Exploration S&ME No. 1351-08-132
tt Proposed Bojangles' Restaurant —Raeford, North Carolina July 9, 2008
V
_I
1. PROJECT DESCRIPTION
We understand that Bcjangles' Restaurant plans to purchase a single -story gas station
property in Raeford, North Carolina and permit, design, and construct a restaurant in its
place. The gas station front is paved and the backyard is grassed. At least two
underground tanks are also located on the property. The area of the site under
consideration is approximately one acre. The restaurant building will be a single -story
structure approximately 40 feet wide by 80 feet long. Surrounding pavements typically
include asphalt -paved driveway(s) and parking spaces with concrete curb and gutter.
2. EXPLORATION PROCEDURES
S&ME, Inc. drilled seven (7) soil test borings (designated B-1 through B-7) to obtain
subsurface information within the proposed building and driveways. The borings were
located in the field by estimating right angles and distances from existing landmarks.
Since the borings were established without survey control, their locations should be
considered approximate. The locations of the borings are shown on the Boring Location
Plan, Figure 1, in the Appendix of this report.
In the proposed restaurant building area boring B-2 was advanced to a depth of 40 feet
below existing grade and borings B-3 and B-4 were advanced to a depth of 20 feet each
below existing grades. In the proposed parking and driveway areas, four borings (B-1, B-
5, B-6 and B-7) were advanced to 10 feet deep each. Borings were performed using a
CME-45 drill rig mounted on a truck using a 2'/n-inch hollow stem auger (HSA).
Samples of subsurface soils were obtained at 2.5-foot intervals above a depth of 10 feet
and at 5-foot intervals below 10 feet using a split spoon sampler. Standard penetration
testing was performed in conjunction with split -spoon sampling in general accordance
with ASTM D 1586. Split -spoon samples obtained from standard penetration testing
were transported to our laboratory and visually classified in general accordance with
Unified Soil Classification System guidelines.
The boreholes were backfilled using auger cuttings after drilling completion. A
Generalized Subsurface Profile drawing (Figure 2) and Test Boring Records presenting
specific subsurface information from the borings are included in the Appendix.
Stratification lines shown on the Test Boring Records and profile are intended to
represent approximate depths of changes in soil types. Natural transitional changes in
soil types are often gradual and vary in both the horizontal and vertical directions.
3. SUBSURFACE CONDITIONS
3.1 Surface Conditions
Surface conditions encountered were typically either a thin layer of grass, exposed soils,
or asphalt.

Report of Subsurface Exploration S&ME No. 1351-08-132
k
Proposed Bojangles' Restaurant —Raeford, North Carolina July 9, 2008
3.2 Soil Conditions
Fill was encountered below topsoil and asphalt in all borings and extended to a depth of
about 3.5 to 5.5 feet. The fill consisted of very loose to medium dense silty and clayey
i sands. Debris and organics were not observed in the fill samples. Standard penetration
test (SPT) N-values in fill ranged from 3 to 14 blows per foot (bpf) indicating little to
some compaction.
Beneath the fill, natural soils were encountered to the boring termination depths. The
natural soils typically consisted of loose to medium dense sands, silty sands and clayey
sands (classified as SM, SP-SM, and SC). Layers of firm to very stiff clay (CL) were
encountered in borings B-2, through B-5 and B-7 at depths from 8 to 13 feet below the
existing ground surface.
-� The Standard Penetration Test (SPT) resistances in sands ranged from 10 to 29 blows per
foot (bp fl. The SPT resistances were 12 to 25 bpf in the silt and clay. The lower
consistency soils (loose sands) were typically encountered in boring B-2 in the upper 12
to 17 feet. Natural soils were damp to moist.
3.3 Subsurface Water
Water was not observed in the borings immediately after drilling completion or in boring
B-4 after 24 hours. Cave-in depths ranging from approximately 7 to 32 feet werer j
recorded in all borings, but water was not observed. Groundwater level measurements
observed in the on site enviro' ... �� � nmental iimohitoring wells, however, show';water ]evel"�" ` �"""
between 30 and 33 feet: It is important to realize that water levels will fluctuate with
changes in rainfall and evaporation rates. In addition, "perched" water conditions can be
present at the surface or within surficial sand layers overlying less permeable materials
(such as clayey sand or clay), especially after rainfall. Long term monitoring of water
levels requires installation of "piezometers" which was beyond the scope of our report.
4. CONCLUSIONS AND RECOMMENDATIONS
4.1 Limitation of Report
This report has been prepared in accordance with generally accepted engineering practice
for specific application to this project. Any wetland, environmental, or contaminant
assessment efforts are beyond the scope of this geotechnical exploration; and therefore,
those issues are not addressed in this geotechnical exploration report. The
recommendations contained in this report are based on the applicable standards of our
profession at the time this report was prepared. No other warranty, express or implied, is
made.
Analysis and recommendations submitted in this report are based upon the data obtained
from the geotechnical exploration and our understanding of the proposed construction.
The nature and extent of variations between and outside of the boring locations may not
become evident until construction. If variations appear evident, then it will be necessary