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Sheetz Shade Tree - Erosion Report 2024-05-15 SEDIMENT & EROSION CONTROL REPORT SHEETZ – SHADE TREE LANE MAY 15, 2024 PREPARED BY: Timmons Group, NC License No. 023728 Patrick Barbeau, PE 5410 Trinity Road, Suite 102 Raleigh, North Carolina 27607 (919) 866-4512 | patric.barbeau@timmons.com www.timmons.com Sheetz – Shade Tree Lane Wilmington, NC Project Number: 64250.002 Table of Contents Sediment & Erosion Control Narrative ............................................................................................................... 1 Project Information ......................................................................................................................................... 1 Proposed Site Improvements ......................................................................................................................... 1 Erosion Control Summary .............................................................................................................................. 1 NPDES/NCG01 Plan...................................................................................................................................... 1 Erosion Control Maintenance Plan ................................................................................................................. 1 Conclusion ..................................................................................................................................................... 1 Sediment & Erosion Control Calculations .......................................................................................................... 2 Sediment Basin Design .................................................................................................................................. 2 Temporary Diversion Ditch Sizing/Liner Calculations ..................................................................................... 2 Pipe Outlet Protection Calculations ................................................................................................................ 2 Maps ................................................................................................................................................................. 3 NOAA Rainfall Data ....................................................................................................................................... 3 USGS Map ..................................................................................................................................................... 3 FEMA FIRM Maps ......................................................................................................................................... 3 NRCS Soil Survey Map .................................................................................................................................. 3 Sheetz – Shade Tree Lane Wilmington, NC Project Number: 64250.002 1 | www.timmons.com Sediment & Erosion Control Narrative Project Information The Sheetz – Shade Tree Lane project is located at 4915 Carolina Beach Road, Wilmington, North Carolina. The property identification number (PIN) is as follows: • R07100-003-024-000 The site consists of approximately 4.4 acres and is currently occupied by a landscaping company. The property will be subdivided, and the resulting Sheetz property will be 2.76 acres (after ROW dedication). FIRM Panel 3720313400K indicates the site is not within a special flood hazard area. There is an existing jurisdictional stream on the property. Permits will be obtained to remove this stream. Proposed Site Improvements This project proposes a new 6,139 SF convenience store and gas canopy with associated parking lot and utilities. Erosion Control Summary The total disturbed area is 5.0 acres. Most of the onsite impervious runoff will be conveyed towards a temporary skimmer sediment basin while the remaining will be protected by silt fence and silt fence stone outlets. After the site has been stabilized, the temporary skimmer basin will be dewatered and removed. NPDES/NCG01 Plan All construction activities shall comply with NCG01 permit guidelines on ground stabilization and materials handling. Erosion Control Maintenance Plan A. All erosion and sediment control practices will be checked for stability and operation following every runoff-producing rainfall, but in no case less than once every week. Any needed repairs will be made immediately to maintain all practices as designed. B. Sediment will be removed from the erosion control devices when storage capacity has been approximately 50 percent filled. C. All seeded areas will be fertilized, reseeded as necessary, and mulched according to specifications to maintain a vigorous, dense vegetative cover. D. Also refer to maintenance requirements listed for each device on plans. Conclusion Erosion control measures for this site have been designed in accordance with Fayetteville requirements and the NCDEQ Erosion and Sediment Control Planning and Design Manual. Sheetz – Shade Tree Lane Wilmington, NC Project Number: 64250.002 2 | www.timmons.com Sediment & Erosion Control Calculations Sediment Basin Design Temporary Diversion Ditch Sizing/Liner Calculations Pipe Outlet Protection Calculations BASIN NAME Basin 1 Sheetz - Shade Tree Ln CALCULATED BY John Hinsley 64250.002 BASIN NAME: Modified Rational Highest Elevation =21 feet Inlet Elevation =13 feet Difference =8 feet Travel Length =468 feet Time of Concentration Length = 300 ft Slope = 1.10 % c-factor = 0.45 12.9 min Length = 168 ft H = 4.7 ft 1.7 min Tc = 14.6 min TC = 15 min Intensity 10 year =6.63 in/hr C =0.45 Disturbed Area =2.24 acres Additional Drainage Area =0.72 acres Total Drainage Area=2.96 acres Q10 =8.83 cfs *RED IS USER INPUT Shallow Concentrated Tc = Basin 1 Time of Concentration Calculation PROJECT NAME PROJECT NUMBER Sheet Flow Sheet Flow Tc = Shallow Concentrated Flow LATEST REVISION: 5/15/2024 7:24 AM Sheetz - Shade Tree Ln 64250.002 Basin Name: Disturbed Area:2.24 ac Additional Drainage Area:0.72 ac Total Drainage Area:2.96 ac Runoff Coeff [Cc]:0.45 10-yr Rainfall Intensity [I]:6.63 in/hr 10-yr Discharge [Q10]:8.83 cfs 4032 Required Volume ft3 (Disturbed Area x 1800 cf/ac) 2870 Required Surface Area ft2 37.9 Suggested Width ft 75.8 Suggested Length ft 42 Width at Surface Area (ft) 84 Length at Surface Area (ft)L/W Ratio =2.0 Okay 3 Side Slope Ratio Z:1 2 Depth (ft) 30 Target Bottom Width (ft) 72 Target Bottom Length (ft) 2160 Target Bottom Area (ft2) 5640 Target Volume (ft3) Okay 3528 Target Surface Area (ft2)Okay 5582 Provided Volume (ft3)Okay 3458 Provided Surface Area (ft2)Okay Skimmer Size 10 Emergency Spillway Width (ft)(Inches) 1 Depth of Flow (ft)1.5 30.0 Spillway Capacity (cfs)Okay 2 2.5 1.5 Skimmer Size (in)3 0.125 Head on Skimmer (ft)4 1.25 Orifice Size (1/4 inch increments)5 3.16 Dewatering Time (days)6 Suggest about 3 days 8 Elevation Area(sf)Depth(ft)Incr. Vol. (cf) 11.00 2152 0 12.00 2777 2465 13.00 3458 3118 Top of Embankment Elevation:14.50 ft Emergency Spillway Elevation:13.00 ft Embankment Width:8 ft Bottom Elevation:11.00 ft Cumulative Volume (cf) 0 2465 5582 0.00 1.00 2.00 (Q10 x 325) PROJECT NAME PROJECT NUMBER BASIN NAME Basin 1 CALCULATED BY Sizing of Basin John Hinsley Sediment Basin Design Basin 1 TYPE OF BASIN:SKIMMER LATEST REVISION: 5/15/2024 7:24 AM TDD100 Area (A) =0.23 (Acres) Coef. (C) = 0.45 (Dimensionless) Inte. (I) =6.63 (in/hr) Flow (Q10) =0.7 (cfs) Line channel with:6 " rip-rap (Assume 6" even if using grass) Manning n =0.030 (Dimensionless)Ditch Length = 191.5 LF Slope =0.042 (ft/ft)Highest Elevation = 21 Z Required =0.07 Ratio Lowest Elevation = 13 Side Slope (M) =3 :1 Flow Depth (Y) =0.50 ft 6.0 in Bottom Width (B) =0.00 ft 0.0 in Freeboard = 0.50 ft 6.0 in T=YxDxS Y = Weight of water (62.4 LB/CUFT) T = 1.30 LB/SF D=Depth of flow in channel (ft) S=Slope of channel (ft/ft) LB/SF Jute Net 0.45 LB/SF Curled Mat 1.55 S75 1.55 Class A (4"@9"THK)2.00 S150 1.75 Class B (8"@18"THK)3.50 SC150 2.10 Class I (12"@22"THK)5.00 C125 2.25 Class II (18"@30"THK)7.50 P300 8.00 New A =0.75 SF New P =3.16 Wetted perimeter New R =0.24 Hydraulic radius Z Actual =0.29 Must be greater than z required=>0.07 Okay New V =3.89 fps Liner:1.55 LB/SF > 1.31 LB/SF Okay Min. Ditch Depth = 1 ft 3 1 Side Slope 3:1 *RED IS USER INPUT Ditch Liner North American Green, S75 North American Green, S75 General Lining North American Green Lining Determine If Z Actual Is Greater Than Z Required Minimum Design Geometry Min. Ditch Depth (ft) 1.00 Bottom Width (ft) Flow Depth (Y) = 0.5 ft Ditch Geometry Bottom Width (B) = 0 ft Top Width (ft)Flow Depth (ft) Drainage Ditch Design (Velocity Constraint) PROJECT NAME PROJECT NUMBER 64250.002 DITCH NAME CALCULATED BY John Hinsley Sheetz - Shade Tree Lane 0.00 0.50 6 TEMPORARY DIVERSION DITCH:TDD100 Top Width = 6 ft Variable Quantities (Ditch Width & Depth) This worksheet is designed to determine channel lining based on flow and ditch geometry (base width, side slope, & channel slope). This program determines depth of flow, velocity and tractive force assuming n=0.03 for grass or rip rap (n can be varied if desired). (Vary depth until z actual equals z required; v & t will be correct; select appropriate lining based on tractive force) Watershed Data Known Quantities Compute Tractive Force LATEST REVISION: 5/15/2024 7:25 AM CALCULATED BY Alex May Pipe Diameter =18 in From Fig. 8.06.c:ZONE =1 Pipe Slope =0.01 ft/ft Mannings n =0.013 Rip Rap Class =A Velocity Flowing Full =5.96 fps Apron Thickness =12 in Apron Length =6.0 ft Apron Width = 3xDia.=4.5 ft From Fig. 8.06.e: Pipe Diameter =15 in From Fig. 8.06.c:ZONE =1 Pipe Slope =0.001 ft/ft Mannings n =0.013 Rip Rap Class =A Velocity Flowing Full =1.67 fps Apron Thickness =12 in Apron Length =5.0 ft Apron Width = 3xDia.=3.8 ft From Fig. 8.06.e: Structure Name:FE120 CCAC Building Solutions PROJECT NAME Pipe Outlet Protection (NYDOT Method) Structure Name:FE300 42929 PROJECT NUMBER LATEST REVISION: 5/15/2024 11:44 AM Sheetz – Shade Tree Lane Wilmington, NC Project Number: 64250.002 3 | www.timmons.com Maps NOAA Rainfall Data USGS Map FEMA FIRM Maps NRCS Soil Survey Map NOAA Atlas 14, Volume 2, Version 3 Location name: Wilmington, North Carolina, USA* Latitude: 34.1515°, Longitude: -77.9033° Elevation: 16 ft** * source: ESRI Maps ** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 6.36(5.93‑6.86)7.56(7.04‑8.16)8.84(8.22‑9.52)9.83(9.11‑10.6)11.1(10.2‑11.9)12.0(11.1‑13.0)13.0(11.9‑14.0)14.0(12.7‑15.1)15.3(13.7‑16.5)16.3(14.5‑17.7) 10-min 5.08 (4.73‑5.48) 6.05 (5.63‑6.52) 7.08 (6.58‑7.63) 7.86 (7.28‑8.47) 8.84 (8.15‑9.50) 9.59 (8.81‑10.3) 10.4 (9.45‑11.1) 11.1 (10.1‑12.0) 12.1 (10.9‑13.1) 12.9 (11.4‑13.9) 15-min 4.23 (3.94‑4.57) 5.07 (4.72‑5.47) 5.97 (5.55‑6.43) 6.63 (6.14‑7.14) 7.47 (6.89‑8.03) 8.10 (7.44‑8.72) 8.72 (7.96‑9.39) 9.34 (8.46‑10.1) 10.1 (9.10‑11.0) 10.8 (9.58‑11.7) 30-min 2.90 (2.70‑3.13) 3.50 (3.26‑3.78) 4.24 (3.94‑4.57) 4.80 (4.45‑5.18) 5.53 (5.10‑5.95) 6.10 (5.60‑6.56) 6.68 (6.10‑7.19) 7.27 (6.59‑7.83) 8.07 (7.24‑8.72) 8.72 (7.76‑9.44) 60-min 1.81 (1.68‑1.95) 2.20 (2.04‑2.37) 2.72 (2.53‑2.93) 3.13 (2.90‑3.37) 3.68 (3.40‑3.96) 4.13 (3.80‑4.45) 4.60 (4.20‑4.95) 5.10 (4.62‑5.49) 5.79 (5.20‑6.26) 6.36 (5.66‑6.89) 2-hr 1.07(0.985‑1.17)1.31(1.20‑1.43)1.66(1.53‑1.81)1.96(1.79‑2.13)2.38(2.17‑2.59)2.74(2.48‑2.98)3.13(2.82‑3.41)3.56(3.19‑3.87)4.19(3.71‑4.57)4.73(4.16‑5.18) 3-hr 0.760 (0.699‑0.835) 0.926 (0.852‑1.02) 1.18 (1.09‑1.30) 1.40 (1.28‑1.54) 1.73 (1.57‑1.89) 2.02 (1.82‑2.20) 2.33 (2.09‑2.55) 2.68 (2.38‑2.92) 3.21 (2.82‑3.50) 3.67 (3.18‑4.02) 6-hr 0.476 (0.437‑0.525) 0.580 (0.534‑0.641) 0.743 (0.681‑0.819) 0.884 (0.806‑0.972) 1.09 (0.990‑1.20) 1.28 (1.15‑1.40) 1.48 (1.32‑1.62) 1.71 (1.51‑1.87) 2.06 (1.79‑2.26) 2.37 (2.04‑2.60) 12-hr 0.277 (0.252‑0.308) 0.338 (0.307‑0.375) 0.436 (0.396‑0.484) 0.521 (0.471‑0.577) 0.649 (0.581‑0.717) 0.762 (0.679‑0.840) 0.890 (0.786‑0.980) 1.03 (0.904‑1.14) 1.26 (1.08‑1.38) 1.45 (1.23‑1.60) 24-hr 0.164 (0.149‑0.182) 0.199 (0.181‑0.221) 0.257 (0.234‑0.286) 0.309 (0.280‑0.343) 0.388 (0.348‑0.431) 0.459 (0.408‑0.509) 0.539 (0.474‑0.599) 0.632 (0.547‑0.703) 0.775 (0.656‑0.868) 0.902 (0.750‑1.02) 2-day 0.096(0.088‑0.106)0.116(0.106‑0.128)0.149(0.136‑0.165)0.178(0.162‑0.197)0.221(0.199‑0.245)0.260(0.232‑0.289)0.304(0.268‑0.338)0.353(0.307‑0.395)0.429(0.365‑0.483)0.496(0.415‑0.562) 3-day 0.068 (0.062‑0.074) 0.082 (0.075‑0.090) 0.104 (0.095‑0.115) 0.124 (0.113‑0.137) 0.153 (0.138‑0.169) 0.179 (0.160‑0.198) 0.207 (0.183‑0.230) 0.240 (0.209‑0.267) 0.289 (0.247‑0.325) 0.333 (0.280‑0.376) 4-day 0.053 (0.049‑0.059) 0.064 (0.059‑0.071) 0.082 (0.075‑0.090) 0.097 (0.088‑0.107) 0.119 (0.107‑0.131) 0.138 (0.124‑0.152) 0.159 (0.141‑0.176) 0.183 (0.160‑0.203) 0.219 (0.188‑0.246) 0.251 (0.212‑0.284) 7-day 0.035 (0.032‑0.038) 0.042 (0.039‑0.046) 0.053 (0.049‑0.058) 0.062 (0.057‑0.068) 0.075 (0.069‑0.082) 0.087 (0.079‑0.095) 0.099 (0.089‑0.108) 0.112 (0.100‑0.123) 0.132 (0.115‑0.146) 0.149 (0.128‑0.166) 10-day 0.027 (0.025‑0.030) 0.033 (0.030‑0.036) 0.041 (0.038‑0.044) 0.047 (0.044‑0.051) 0.057 (0.052‑0.062) 0.065 (0.059‑0.071) 0.074 (0.067‑0.081) 0.084 (0.075‑0.091) 0.097 (0.086‑0.107) 0.109 (0.095‑0.121) 20-day 0.018(0.017‑0.019)0.022(0.020‑0.023)0.026(0.025‑0.029)0.030(0.028‑0.033)0.036(0.033‑0.039)0.041(0.038‑0.044)0.046(0.042‑0.050)0.051(0.046‑0.056)0.059(0.052‑0.064)0.065(0.057‑0.072) 30-day 0.015 (0.014‑0.016) 0.018 (0.017‑0.019) 0.021 (0.020‑0.023) 0.024 (0.023‑0.026) 0.028 (0.026‑0.030) 0.032 (0.029‑0.034) 0.035 (0.032‑0.038) 0.038 (0.035‑0.041) 0.043 (0.039‑0.047) 0.047 (0.042‑0.052) 45-day 0.012 (0.011‑0.013) 0.014 (0.014‑0.015) 0.017 (0.016‑0.018) 0.019 (0.018‑0.021) 0.023 (0.021‑0.024) 0.025 (0.023‑0.027) 0.028 (0.025‑0.030) 0.030 (0.028‑0.032) 0.034 (0.031‑0.036) 0.037 (0.033‑0.040) 60-day 0.011 (0.010‑0.012) 0.013 (0.012‑0.014) 0.015 (0.014‑0.016) 0.017 (0.016‑0.018) 0.019 (0.018‑0.021) 0.021 (0.020‑0.023) 0.023 (0.022‑0.025) 0.025 (0.023‑0.027) 0.028 (0.025‑0.030) 0.030 (0.027‑0.032) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (fora given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are notchecked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical 5/9/24, 9:30 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=34.1515&lon=-77.9033&data=intensity&units=english&series=pds 1/3 National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOODHAZARD AREAS Without Base Flood Elevation (BFE)Zone A, V, A99With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areasof 1% annual chance flood with averagedepth less than one foot or with drainageareas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREENArea of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below.The basemap shown complies with FEMA's basemapaccuracy standards The flood hazard information is derived directly from theauthoritative NFHL web services provided by FEMA. This mapwas exported on 5/15/2024 at 8:07 AM and does notreflect changes or amendments subsequent to this date andtime. The NFHL and effective information may change orbecome superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximatepoint selected by the user and does not representan authoritative property location. 1:6,000 77°54'31"W 34°9'19"N 77°53'54"W 34°8'49"N Basemap Imagery Source: USGS National Map 2023 United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for New Hanover County, North Carolina Natural Resources Conservation Service May 8, 2024 6 Custom Soil Resource Report Soil Map 37 8 2 6 0 0 37 8 2 6 4 0 37 8 2 6 8 0 37 8 2 7 2 0 37 8 2 7 6 0 37 8 2 8 0 0 37 8 2 8 4 0 37 8 2 8 8 0 37 8 2 9 2 0 37 8 2 6 0 0 37 8 2 6 4 0 37 8 2 6 8 0 37 8 2 7 2 0 37 8 2 7 6 0 37 8 2 8 0 0 37 8 2 8 4 0 37 8 2 8 8 0 232200 232240 232280 232320 232360 232400 232200 232240 232280 232320 232360 232400 34° 9' 10'' N 77 ° 5 4 ' 1 7 ' ' W 34° 9' 10'' N 77 ° 5 4 ' 7 ' ' W 34° 8' 59'' N 77 ° 5 4 ' 1 7 ' ' W 34° 8' 59'' N 77 ° 5 4 ' 7 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,590 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: New Hanover County, North Carolina Survey Area Data: Version 25, Sep 13, 2023 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Nov 8, 2022—Dec 1, 2022 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 7 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI Le Leon sand 3.0 51.0% Ly Lynn Haven fine sand 1.9 33.0% St Stallings fine sand 0.9 15.9% Totals for Area of Interest 5.9 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, Custom Soil Resource Report 8 17 Custom Soil Resource Report Map—Hydrologic Soil Group 37 8 2 6 0 0 37 8 2 6 4 0 37 8 2 6 8 0 37 8 2 7 2 0 37 8 2 7 6 0 37 8 2 8 0 0 37 8 2 8 4 0 37 8 2 8 8 0 37 8 2 9 2 0 37 8 2 6 0 0 37 8 2 6 4 0 37 8 2 6 8 0 37 8 2 7 2 0 37 8 2 7 6 0 37 8 2 8 0 0 37 8 2 8 4 0 37 8 2 8 8 0 232200 232240 232280 232320 232360 232400 232200 232240 232280 232320 232360 232400 34° 9' 10'' N 77 ° 5 4 ' 1 7 ' ' W 34° 9' 10'' N 77 ° 5 4 ' 7 ' ' W 34° 8' 59'' N 77 ° 5 4 ' 1 7 ' ' W 34° 8' 59'' N 77 ° 5 4 ' 7 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,590 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: New Hanover County, North Carolina Survey Area Data: Version 25, Sep 13, 2023 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Nov 8, 2022—Dec 1, 2022 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 18 Table—Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI Le Leon sand A/D 3.0 51.0% Ly Lynn Haven fine sand A/D 1.9 33.0% St Stallings fine sand A/D 0.9 15.9% Totals for Area of Interest 5.9 100.0% Rating Options—Hydrologic Soil Group Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Custom Soil Resource Report 19