20080648 Ver 1_More Info Received_20080731

LMG
LAND MANAGEMENT GROUP INC.
Environmental Consultants
July 28, 2008
TO: Mr. Chad Coburn
NC Division of Water Quality
127 Cardinal Drive Extension
Wilmington, NC 28405
RE: Additional Information for the 401 Water Quality Certification
Lot 4, Swordfish Lane; New Hanover County, NC
DWQ Project # 08-0648
Dear Chad:
As requested, enclosed is the stormwater management plan and associated worksheets for Lot 4 off
of Swordfish Lane in Carolina Beach, NC. I believe you should have all of the information necessary
to issue a 401 Water Quality Certification for this project.
Thank you for your assistance with this project.
Sincerely, _
L -lam
Kim Williams
Environmental Scientist
Encl.
QcQ? 12 ad9 B
JUL 3 0 2008
DENR • WATER QUAUTY
C: Mr. Scott Jones WETLANDS AND STORMWATER BRANCH
Mr. Ian McMillan, DWQ
www.lmgroup.net • [e-mail] • Phone: [phone] • Fax: [phone]
3805 Wrightsville Ave., Suite 15, Wilmington, NC 28403 • P.O. Box 2522, Wilmington, NC 28402
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STORMWATER MANAGEMENT CALCULATIONS
For
LT 4
1216 Swordfish lane
PREPARED FOR
Scott Jones
703 St. Joseph St. suite 101
Carolina Beach, NC 28428
Prepared by:
COASTAL SITE DESIGN, PC
PO Box 4041
Wilmington, NC 28406
Phone [phone]
Fax: [phone]
!
?WX
L? O'F5EA1L .A' F:1r
F2 C RtN
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?'JmydG' /
Howard Resnik, P.E.
// ?
, 0J
HYDROLOGIC DATA:
Existing data pre-development condition):
existing undeveloped sandy/grassed area
existing wetlands
Total area

Proposed data (post development condition
proposed impervious surface
proposed grassed/landscaped area
Total area
4,353 sf (0.10 acres)
647 sf (0.01 acres)
5,000 sf (0.11 acres)
2,400 sf (0.06 acres)
2,600 sf (0.06 acres)
5,000 sf (0.11 acres)
Soil Types:
Abbreviation Type and Description Hydrologic Group
Le Leon B/D
(See attached soils map from New Hanover County Soils Survey & soils report enclosed)
ftsw SRO Designs PC
e P.O. Box 4041
WW" IC 2MM
STORMWATER MANAGEMENT FOR CAROLINA BEACH:
PRE-DEVELOPED CONDITIONS (see hydrograph summary and reports):
- Pre-dev.
CN Pre Developed = 77 (SCS) - Soils are D - WOODS:
Area = 5,000 sf or 0.11 acres
Hydraulic length = 75 ft
Basin slope =.01%
Qmax for pre-dev 10-yr = 0.17 cfs
POST-DEVELOPED CONDITIONS (see hydrograph summary and reports):
Area to Trech
- Post-dev to trench (before routing)
CN Post Developed = 98 (SCS) composite value determined as follows:
- +/- 2,400 sf of impervious surface (CN = 98)
Area = 2,400 sf or 0.06 acres
Hydraulic length = 70 ft
Basin slope = 0.01%
Qmax for post-dev 10-yr = 0.21 cfs
Area offsite
- Post-dev offsite
CN Post Developed = 61 (SCS) composite value determined as follows:
- +/- 2,600 sf of soils are B, lawn - good condition (CN = 61)
Area = 2,600 sf or 0.06 acres
Hydraulic length = 10 ft
Basin slope= 0.01%
Qmax for post-dev 10-yr = 0.10 cfs
Coastal Site Design, PC
P.O. Box 4041
Whinpton, NC 28406
- Routed-site -areas routed through system
Qmax for post-route 10-yr = 0.00 cfs
SUMMARY:
Total Pre Development Flows:
Qmax for pre-dev 10-yr storm = 0.17 cfs
Total Post Development Flows:
Qmax for post-dev. 10 yr storm= 0.00 + 0.10 = 0.10 cfs < 0.17 cfs...O.$
Coastal Site Design, PC
P.0, Box 4041
Wii*004 NC 28408
UNDERGROUND INFILTRATION TRENCH
ULTIMATE 1-0" VOLUME DETERMINATION:
DETERMINE IMPERVIOUS PERCENTAGE
area to infiltration system = 2,400 sf
= 0.06 acres
buildings = 2,000 sf
asphalt = - sf
parking = 400 sf
sidewalks = - sf
pump station = - sf
total imp. surface = 2,400 sf
percent imp. = 100.0 %
DETERMINE RUNOFF COEFFICIENT (Rv)
I = 100.0 percent impervious
Rv = ? (runoff coefficient, inches per inch)
Rv = 0.05 + 0.009 (1)
Rv = 0.95 in/in
DETERMINE VOLUME
design storm = 1 inch
RV = 0.95 in/in
drainage area = 0.06 acres
volume = ?
volume = (design storm) (Rv)(drainage area)
volume = 0.0 acre-ft
volume = 190 cf of required storage volume built out condition
COASTAL SITE DESIGN,PC
PO BOX 4041
WILMINGTON, NC 28406
INFILTRATION SYSTEM STAGE - STORAGE TABLE
INFILTRATION TRENCH 1:
pipe size (in) = 8
pipe length (ft) = 212
total trench width (ft) = 4.82
total trench length (ft) = 108
trench invert elevation (ft) = 8
TOTAL PIPE TOTAL STONE TOTAL
d/D area/D^2 STAGE ELEVATION STORAGE STORAGE STORAGE
(FT) (CF) (CF) (CF)
0.000 8 -
0.067 8.07 - 14 14
0.133 8.13 - 28 28
0 0 0.200 8.20 - 42 42
0.1 0.0409 0.267 8.27 4 54 58
0.2 0.1118 0.333 8.33 11 65 76
0.3 0.1982 0.400 8.40 19 76 94
0.4 0.2934 0.467 8.47 28 86 114
0.5 0.3927 0.533 8.53 37 96 133
0.6 0.4920 0.600 8.60 46 106 153
0.7 0.5872 0.667 8.67 55 117 172
0.8 0.6736 0.733 8.73 63 127 191
0.9 0.7445 0.799 8.80 70 138 208
1 0.7854 0.865 8.86 74 150 224
0.931 8.93 74 164 238
0.997 9.00 74 178 252
1.063 9.06 74 192 266
1.129 9.13 74 205 279
1.195 9.19 74 219 293
1.261 9.26 74 233 307
1.327 9.33 74 247 321
1.393 9.39 74 260 334
1.459 9.46 74 260 334
1.525 9.52 74 260 334
1.591 9.59 74 260 334
1.657 9.66 74 260 334
total 1" storage volume provided in trench (elev.8.73) = 191 cf
TRENCH INFILTRATION:
linear infiltration rate = 4 in/hr
= 0.000093 fUsec
trench bottom area = 521 sf
3-d infiltration rate = 0.05 cf/sec
drawdown time = 65.9 minutes
or
1.1 hours
or
0.05 days
COASTAL SITE DESIGN,PC
PO BOX 4041
WILMINGTON, NC28406
Hydrograph Summary Report
Hydraflow Hydrographs by Intelisolve Al
Hyd.
No. Hydrograph
type
(origin) Peak
flow
(cfs) Time
interval
(min) Time to
peak
(min) Hyd.
volume
(cult) Inflow
hyd(s) Maximum
elevation
(ft) Total
strge used
(cult) Hydrograph
description
1 SCS Runoff 0.168 2 762 1,751 - -- - Pre_dev
2 SCS Runoff 0.209 2 738 1,473 - -- - Post_Dev
3 Reservoir 0.000 2 660 0 2 10.22 305 Routed
5 SCS Runoff 0.101 2 740 596 - -- - OFF-SITE
Coastal $Its Design, PC
PO
BOX 4041
.
Wilmington, NC 28408
Pre_Post.gpw Return Period: 10 Year Monday, Jul 28, 2008
Hydrograph Report
Hydraflow Hydrographs by Intelisolve v9.1
Hyd. No. 1
Pre_dev
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval = 2 min
Drainage area = 0.110 ac
Basin Slope = 0.0%
Tc method = LAG
Total precip. = 7.00 in
Storm duration = 24 hrs
Monday, Jul 14, 2008
Peak discharge = 0.168 cfs
Time to peak = 762 min
Hyd. volume = 1,751 cuft
Curve number = 77
Hydraulic length = 75 ft
Time of conc. (Tc) = 43.92 min
Distribution = Type III
Shape factor = 242
Pre_dev
Q (afs) Hyd. No. 1 -- 10 Year
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)
Coastal Site Design$ PC
® P.O. Box 4041
Wilmington, NO 28408
Hydrograph Report
Hydraflow Hydrographs by Intelisolve Al Monday, Jul 14, 2008
Hyd. No. 2
Post Dev
Hydrograph type = SCS Runoff Peak discharge = 0.209 cfs
Storm frequency = 10 yrs Time to peak = 738 min
Time interval = 2 min Hyd. volume = 1,473 cuft
Drainage area = 0.060 ac Curve number = 98
Basin Slope = 0.0% Hydraulic length = 70 ft
Tc method = LAG Time of conc. (Tc) = 17.97 min
Total precip. = 7.00 in Distribution = Type III
Storm duration = 24 hrs Shape factor = 242
Post_Dev
Q (Cfs) Hyd. No. 2 --10 Year Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 2 Time (min)
A Coastal Site Design, PC
P0. Box 4041
Wiminoon, NC 28406
Hydrograph Report
Hydraflow Hydrographs by Intelisolve v9.1 Monday, Jul 14, 2008
Hyd. No. 3
Routed
Hydrograph type = Reservoir Peak discharge = 0.000 cfs
Storm frequency = 10 yrs Time to peak = 660 min
Time interval = 2 min Hyd. volume = 0 cuft
Inflow hyd. No. = 2 - Post _Dev Max. Elevation = 10.22 ft
Reservoir name = Trench Max. Storage = 305 cuft
Storage Indication method used. Exfiltration extracted from Outflow.
Q (cfs;
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
Routed
Hyd. No. 3 -- 10 Year

Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
i
ftww' -'.u
0.00 r. t. 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 3 Hyd No. 2 i.-Total storage used = 305 cuft
CoWal Site Design, PC
P,0- Box 4041
Wilmington, NC 28406
Pond Report
Hydraflow Hydrographs by Intelisolve v9.1 Monday, Jul 14, 2008
Pond No. 1 - Trench
Pond Data
UG Chambers - Invert elev. = 8.50 ft, Rise x Span = 0.66 x 0.66 ft, Barrel Len = 106.00 ft, No. Barrels = 2, Slope = 0.00%, Headers = Yes
Encasement - Invert elev. = 8.00 ft, Width = 2.40 ft, Height = 1 .66 It, Voids = 40.00%
Stage / Storage Table
Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft)
0.00 8.00 n/a 0 0
0.17 8.17 n/a 35 35
0.33 8.33 n/a 35 71
0.50 8.50 n/a 35 106
0.66 8.66 n/a 44 150
0.83 8.83 n/a 49 199
1.00 9.00 n/a 49 249
1.16 9.16 n/a 44 293
1.33 9.33 n/a 35 328
1.49 9.49 n/a 35 363
1.66 9.66 n/a 35 399
Culvert / Orifice Structures Weir Structures
[A] [B] [C] [PrfRsr] [A] [B] [C] [D]
Rise (in) = 0.00 0.00 0.00 0.00 Crest Len (ft) = 0.00 0.00 0.00 0.00
Span (in) = 0.00 0.00 0.00 0.00 Crest El. (ft) = 0.00 0.00 0.00 0.00
No. Barrels = 0 0 0 0 Weir Coeff. = 3.33 3.33 3.33 3.33
Invert El. (ft) = 0.00 0.00 0.00 0.00 Weir Type = - - - -
Length (ft) = 0.00 0.00 0.00 0.00 Multi-Stage = No No No No
Slope (%) = 0.00 0:00 0.00 n/a
N-Value = .013 .013 .013 n/a
Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfii.(in/hr) = 4.000 (by Wet area)
Multi-Stage = n/a No No No TW Elev. (ft) = 0.00
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s).
Stage (ft)
2.00 .
1.80-
1.60 .
1.40 -
1.20 -
1.00-
0.80 -
0.60 -
0.40
0.20
0 00
Stage / Discharge
Elev (ft)
10.00
9.80
9.60
9.40
9.20
9.00
8.80
8.60
8.40
8.20
8 00
0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.1we?nstal 861 besign j?o
harge (cfs)
?°? Total Q P.O. Sox 4041
Wilmington, NC 28406
Hydrograph Report
Hydraflow Hydrographs by Intelisolve Al
Hyd. No. 5
OFF-SITE
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval = 2 min
Drainage area = 0.060 ac
Basin Slope = 0.0%
Tc method = LAG
Total precip. = 7.00 in
Storm duration = 24 hrs
OFF-SITE
Q (cfs)
Hyd. No. 5 -- 10 Year
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00 ' l 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 5 Time (min)
C03stfll Site Design, PC
A P.O, Box 4041
Wilmington, NC 28406
Monday, Jul 28, 2008
Peak discharge = 0.101 cfs
Time to peak = 740 min
Hyd. volume = 596 cuft
Curve number = 61
Hydraulic length = 10 ft
Time of conc. (Tc) = 13.50 min
Distribution = Type III
Shape factor = 242
CHART E-5
Depth Duration. Frequency Table
Location: Wilmington, NC
Return Period
Duration 2-yr 5-yr 10-yr 25-yr 50-yr 100-yr
[in] [in] [in] [in] [in] [in]
5 min 0.49 0.55 0.60 0:68 0.74 0.80
10 min 0.84 0.96 1.05 1.19 1.30 1.41
15 min 1.09 1.24 1.36 1.54 1.69 1.83
30 min 1.58 1.90 2.12 2.46 2.72 2.98
60.min 2.10 2.58 2.92 -3.41 3.80 4.18
2 hr 2.36 2.93 3.34 3.92 4.37 4.82
3 hr 2.63 3.29 3.76 4.42 4.94 5.46
6 hr 3.30 4.20 4.82 5.71 6.40 7.09
12hr 3.90 5.00 5.77 6.86 7.70 8.55
24hr 4.50 5.81 6.72 8.01 9.01 10.00
CHART E-6
Intensity - Duration - Frequency Table
T .nentinn • Wilrninn+nn NP

Return Period
Duration 2-yr 5-yr 10-yr 25-yr 50-yr 100yr
[ice] [in/hr] [in/br] [in/hr] [in/hr] [in1r]
5 min 5.88 6.63 7.23 8.15 8.87 9.60
10 min 5.06 5.76 6.30 7.13 7.79 8.45
15 min 4.36 4.97 5.45 6.17 6.75 7.32
30 min 3.17 3.79 4.25 4.92 5.44 5.96
60 min 2.10. 2.58 2.92 3.41 3.80 4.18
2hr 1.18 1.47 1.67 1.96 2.19 2.41
3hr 0.88 1.10 1.25 1.47 1.65 1.82
6hr 0.55 0.70 0.80 0.95 1.07 1.18
12 hr 0.33 0.42 0.48 0.57 0.64 0.71
24 hr 0.19 0.24 0.28 0.33 0.38 0.42
*Source: Master Drainage Improvement and Stormwater Management Plan, Vol. 1, McKim &
Creed, June 1988
Coastal Site Design, pC
P.O. Box 4041
Wilmington, NC 28406
5-16
?\1
TABLE H-1
Hydrologic Soil Groups for Local Soil Types
Map Hydrologic Soil Type
Symbol Soil
group
Ba D Bayboro
Be A Baymeade
Bh * Baymeade-Urban Land Complex
Bp * Borrow Pit
Cr C Craven
DO D Dorovan
JO D Johnston
Ke A Kenansville
Kr A Kureb
Ku * Kureb-Urban Land Complex
La A Lakeland
Le B/D Leon
Lo * Leon-Urban Land Complex
Ls C Lynchburg
Ly B/D Lynn Haven -
MP * Mine Pits
Mu A/D Murville
Nh A Newhan
No B Norfolk
On B Onslow
Pm D Pamlico
Pn B/D Pantego
Ra B/D Rains
Rm A Rimini
Se A/D Seagate
Sb * Seagate-Urban Land Complex
St C Stallings
TM * Tidal Marsh
To C Torhunta
Ur * Urban Land
Wa A Wakulla
Wo B/D Woodington
Wr C Wrightsboro
* Requires field Judgment
A/D Refers to drained/undrained.
Sources: Urban Hydrology for Small Watersheds , USDA-SCS, 210-VI-TR-55, Second Bd.,
June 1986.
Coastal Site Design, PC -
i
P0, Box 4041
. i
`Wilmington, NC 284
06
5-52 I
Appendices

Table 8.03e Runoff curve numbers of urban areas'
Curve number for
-----------------------------------Cover Description---------------------- -------hydrologic soil group-------
Cover type and hydrologic condition Average percent 2 A B C D
impervious area'
Fully developed urban areas (vegetation established)
Open space (lawns, parks, golf courses, cemeteries, etc.) 3:
Poor condition (grass cover < 50%) ............................. 68 79 86 89
Fair condition (grass cover 50% to 75%) ..................... 49 69 79 84
Good condition (grass cover > 75%) ............................ 39 61 74 80
Impervious areas:
Paved parking lots, roofs, driveways, etc. 98 98 98 98
(excluding right-of-way) ...............................................
Streets and roads:
Paved; curbs and storm sewers (excluding 98 98 98 98
right-of-way) ..................................................................
Paved; open ditches (including right-of-way) ................ 83 89 92 93
Gravel (including right-of-way) ...................................... 76 85 89 91
Dirt (including right-of-way) ........................................... 72 82 87 89
Urban districts:
Commercial and business ................................................. 85 89 92 94 95
Industrial ........................................................................... 72 81 88 91 93
Residential districts by average lot size:
1/8 acre or less (town houses) ......................................... 65 77 85 90 92
114 acre ........................................................ .................:.. 38 61 .75 83 87
1/3 acre ............................._............................................... 30 57 72 81 86
1 /2 acre ............................................................................. 25 54 70 80 85
1 acre ............................................................................... 20 51 68 79 84
2 acres .............................................................................. 12 46 65 77 82
Developing urban areas
Newly graded areas

(pervious areas only, no vegetation) 4 ........................ 77 86 91 94
Idle lands (CN's are determined using cover types
similar to those in table 2-2c).
1. Average runoff condition, and la = 0.2S.
2. The average percent impervious area shown was used to develop the composite CN's. Other assumptions are as follows: impervious
areas are directly connected to the drainage system, impervious areas have a CN of 98, and pervious areas are considered equivalent
to open space in good hydrologic condition. CN's for other combinations of conditions may be computed using Figure 8.03c or 8.03d.
3. CN's shown are equivalent to those of pasture. Composite CN's may be computed for other combinations of open space cover type.
4. Composite CN's to use for the design of temporary measures during grading and construction should be computed using Figure 8.03c
or 8.03d based on the degree of development (impervious area percentage) and the CN'ss fan ev rbg3:???r<C
P0. Box 4041
Rev. 6r06 ` ' `? Wilmington, NC 28406 . 8I •o3.15

Appendices
Table 8.03g Runoff curve numbers for other agriculture lands'
Curve numbers for
--------------------Cover description----------------------- ---------- -hydrologic soil groups-------
Hydrologic
Cover type conditions' A B C D
Pasture, grassland, or range- Poor 68 79 86 89
continuous forage for grazing. 2
Fair 49 69 79 84
Good 39 61 74 80
Meadow-continuous grass, protected - 30 58 71 78
from grazing and generally mowed for
hay.
Brush-brush-weed-grass mixture with Poor 48 67,' 77 83
brush the major element.'
Fair 35 56 70 77 N
Good 304 48 65 73
Woods-grass combination (orchard or Poor 57 73 82 86
tree farm). 5
Fair 43 65 76 82
Good 32 58 72 79
Woods.5 Poor 45 66 77 83
Fair 36 60 73 79
Good 304 55 70 77
Farmsteads-buildings, lanes, - 59 74 82 86
driveways, and surrounding lots.
1 Average runoff condition, and la = 0.2S.
2 Poor <50% ground cover or heavily grazed with no mulch.
Fair.• 50 to 75% ground cover and not heavily grazed.
Good: > 75% ground cover and lightly or only occasionally grazed.
3 Poor: <50% ground cover.
Fair.' 50 to 75% ground cover.
Good: >75% ground cover.
4 Actual curve number is less than 30; use CN = 30 for runoff computations.
5 CN's shown were computed for areas with 50% woods and 50% grass (pasture) cover. Other combinations of
conditions may be computed from the CN's for woods and pasture.
6 Poor Forest litter, small trees, and brush are destroyed by heavy grazing or regular burning.
Fair: Woods are grazed but not burned, and some forest litter covers the soil.
Good: Woods are protected from grazing, and litter and brush adequately cover the soil.
Coastal Site Design, PC
P.O. Box 4041
AWilmington; NC 28406
Rev. 6/06 8.03.17
NEW HANOVER, NORTH CAROLINA 63
TABLE 14.--PHYSICAL AND CHEMICAL PROPERTIES OF SOILS
Dashes indicate data were not available. The symbol < means less than; > means greater than.
Absence of an entry means data were not estimated]
!Available! 1 Shrink- 1- x1sk or corrosion
Soil name and !Depth! Permea- ! water 1 Soil 1 swell ; Uncoated
map symbol i i bility !capacity !reaction !potential J steel ; Concrete
: In : In per i In per i Ph
hour : in of Ir i
! Soil
Bayboro: .i
Ba----------------i 0-16: 0.6-2.0 10.15-0.201 4.5-5.5 !Low ------- !High --------- :High.
116-7210.06-0.2 10.14-0.181 4.5-5.5 !Moderate !High --------- :High.
I I
Baymeade:
Be, 1Bh----------- : 0-361 6.0-20 10.02=0.061 5.1-6.5 !Low ------- !Low ---------- :Moderate.
:36-491 2.0-6.0 10.10-0.141 5.1-6.5 :Low ------- !Low ---------- :Moderate.
:49-781 6.0-20 .4'0.02-0.101 5.1-6.5 :Low ------- !Low ---------- !Moderate.
I I I I I 1 !
I I 1 I 1 I
Borrow pits: ! ! : ! ! ! !
Bp.
Craven:
Cr---------------- 1 0-8 : 0.6-2.0 :0.12-0.181 4.5-6.0 !Low ------- !High --------- !High.
! 8-641 <0.2 10.12-0.151 4.5-5.5 :Moderate !High --------- !High.
Dorovan:. ! !
1DO--------------- 1 0-4 ! <0.06 10.25-0.501 4.5-5.5 1---------- :High --------- !High.
! 4-64! <0.06 10.25-0.501 4.5-5.5 1---------- :High --------- !High.
! ! ! : : : :
Johnston: 1 1 1 1 : !
1JO--------------- 1 0-421 2.0-6.0 10.10-0.201 4.5-5.5 !Low ------- !High --------- !High.
142-641 6.0-20 :0.06-0.121 4.5-5.5 :Low ------- !High --------- ;High.
i I I I I I I
I I I I I I I
Kenansville:
Ke---------------- ! 0-331 6.0-20 10.04-0.101 4.5-6.0 :Low ------- !Low ---------- :High.
133-501 2.0-6.0 10.10-0.141 4.5-6.0 !Low ------- :Low ---------- !High.
:50-80: 6.0-20 ! <0.05 ! 4.5-6.0 !Low ------- !Low ---------- !High.
I I I I I I !
i I I I I I
Kureb: : ! ! ! ! ! 1
Kr----------------1 0-891 6.0-20 : <0.05 1 4.5-7.3 !Low------- !Low ---------- !Low.
! ! ! ! 1 : 1
1Ku: ! ! : : : ! !
Kureb part-------1 0-891 6.0-20 : <0.05 1 4.5-7.3 !Low ------- !Low ---------- !Low.
I I
Urban land part. ! : ! ! ! !
! I I I 1 I I
Lakeland:
La----------------1 0-48! >20 10.05-0.081 4.5-6.0 ;Very low !Low----------!Moderate.
148-80! >20 10.03-0.081 4.5-6.0 !Very low !Low----------!Moderate.
I !
Leon: 1 : : : ! 1
Le, 1Lo----------- 1 0-6 1 6.0-20 :0.02-0.051 3.6-5.5 !Very low !High --------- !High.
! 6-301 0.6-6.0 :0.05-0.101 3.6-5.5 !Very low :High --------- !High.
130-80: >20 :0.02-0.051 3.6-5.5 :Very low !High --------- :High.
Lynchburg: ! : ! ! ! ! 1
Ls----------------1 0-6 1 2.0-6.0 10.09-0.131 3.6-5.5 !Low ------- :High--------- !High.
1 6-641 0.6-2.0 10.12-0.161 3.6-5.5 !Low ------- !High--------- !High.
I ! !
Lynn Haven: ! ! ! : : ! !
Ly---------------- ! 0-241 6.0-20 10.02-0.051 3.6-5.5 :Very low !High --------- !High.
124-641 0.6-6.0 10.05-0.101 3.6-5.5.:Very low !High --------- !High.
164-751 >20 10.01-0.05: 3.6-5.5 !Very low !High --------- !High.
! ! ! ! ! : 1
Mine pits:
I I
Mp. : ! ! : !
I I I I I I' I
I I I I I I I
Murville:
Mu----------------1 0-8 : 6.0-20 :0.05-0.091 3.6-5.5 :Low------- :High --------- !Moderate.
! 8-601 2.0-6.0 10.05-0.091 3.6-5.5 !Low ------- !High--------- !Moderate.
:60-701 6.0-20 .10.04-0.071 3.6-5.5 !Low ------- ;High --------- !Moderate.
I I I I I I I
I I I I I I
See footnotes at end of table.
Coastal site Design, PC
P.O, Box 4041
Wilmington, NC 28406
}C })1
?t