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HomeMy WebLinkAboutSW8120114_COMPLIANCE_20120815STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW E&2k,Y DOC TYPE ❑ CURRENT PERMIT ❑ APPROVED PLANS ❑ HISTORICAL FILE FA COMPLIANCE EVALUATION INSPECTION DOC DATE ��IS YYYYMMDD Compliance Inspection Report Permit: SW8120114 Effective: 07/23/12 Expiration: 07/23/20 Owner: Flowers Development Corporation Inc Project: Flowers Developent Corporation County: Carteret 310 Friendly Rd Region: Wilmington Contact Person: Richard C Flowers Title: Directions to Project: Off Bridges Street. Type of Project: State Stormwater - HD - Detention Pond Drain Areas: 1 - (Peltier Creek) (03-05-03 } ( SB:#) On -Site Representatives): Related Permits: Inspection Date: 0811512012 Entry Time: 01:30 PM Primary Inspector: Christine Nelson Secondary Inspectors): Reason for Inspection: Other Permit Inspection Type: State Stormwater Facility Status: ❑ Compliant ® Not Compliant Question Areas: IN State Stormwater (See attachment summary) Morehead City NC 28557 Phone: 252-247-7809 Exit Time: 02:00 PM Phone: 910-796-7215 Inspection Type: Compliance Evaluation Page: 1 Permit: SW8120114 owner - Project: Flowers Development Corporation Inc Inspection Date: 08/15/2012 Inspection Type: Compliance Evaluation Reason for Visit: Other Inspection Summary: The following deficiencies were noted during the inspection: The BMP has not been installed and the collection system has not been constructed as approved. The runoff from the newly constructed impervious area appears to be directed to a perimeter Swale. Per Section 11.1 of the permit: The stormwater management system shall be constructed in its entirety, vegetated and operational prior to the construction of any built -upon area. To bring this system into compliance, the BMP and collection system must be installed and constructed as approved and the designer's certification must•be submitted. Page: 2 10 Permit: SW8120114 Owner - Project: Flowers Development Corporation Inc Inspection Date: 08/15/2012 Inspection Type: Compliance Evaluation Reason for Visit: Other File Review Yes No NA NE Is the permit active? ® ❑ ❑ ❑ Signed copy of the Engineer's certification is in the file? ❑ ■ ❑ ❑ Signed copy of the Operation & Maintenance Agreement is in the file? ®❑ ❑ ❑ Copy of the recorded deed restrictions is in the file? ❑ ❑ © ❑ Comment: A copy of the engineer's certification has not been received. Built Upon Area Yes No NA NE Is the site BUA constructed as per the permit and approval plans? ®❑ ❑ ❑ Is the drainage area as per the permit and approved plans? ❑ ®❑ ❑ Is the BUA (as permitted) graded such that the runoff drains to the system? ❑ M Q ❑ Comment: Only the proposed building and gravel in the front of the property have been installed. The collection system has not been constructed as approved. SW Measures Yes No NA NE Are the SW measures constructed as per the approved plans? ❑ ®❑ ❑ Are the inlets located per the approved plans? ❑ ®❑ ❑ Are the outlet structures located per the approved plans? ❑ ® ❑ ❑ Comment: The BMP has not been installed and the collection system has not been constructed as approved. The runoff from the newly constructed impervious area appears to be directed to a perimeter swale. Operation and Maintenance Yes No NA NE Are the SW measures being maintained and operated as per the permit requirements? ❑ ❑ ® ❑ Are the SW BMP inspection and maintenance records complete and available for review or provided to DWQ ❑ ❑ ® ❑ upon request? Comment: The BMP has not been installed. Other Permit Conditions Yes No NA NE Is the site compliant with other conditions of the permit? ❑ ®❑ ❑ Comment: Per Section 11.1 of the permit: The stormwater management system shall be constructed in its entirety, vegetated and operational prior to the construction of any built -upon area. Other WQ Issues Yes No NA NE Is the site compliant with other water quality issues as noted during the inspection? ❑ ❑ ❑ Comment: Page: 3 Compliance Inspection Report Permit: SW8120114 Effective:07123112 Project: Flowers Development Corporation Owner: Flowers Development Corporation Inc County: Carteret Region: Wilmington Contact Person: Richard C Flowers Directions to Project: Off Bridges Street. Expiration: 07/23/20 Type of Project: State Stormwater - HD - Detention Pond Drain Areas: 1 - (Peltier Creek) (03-05-03.) ( SB:#) On -Site Representative(s): Related Permits: Title: Adress: 310 Friendly Rd City/State/Zip: Morehead City NC 28557 Inspection Date: 09/09/2015 Entry Time: 08:OQAM Primary Inspector: Christine A Hall Secondary Inspector(s): Reason for Inspection: Follow-up Permit Inspection Type: State Stormwater Facility Status: ❑ Compliant ® Not Compliant Question Areas: ® State Stormwater (See attachment summary) Phone: 252-247-7809 Exit Time: 08:30AM Phone: 910-796-7215 Inspection Type: Compliance Evaluation page: Permit: SW8120114 Owner - Project: Flowers Development Corporation I nc Inspection Date: 09/09/2015 inspection Type Compliance Evaluation Reason for Visit: Follow-up Inspection Summary: Please provide a copy of the completed designers certification. File Review Yes No NA NE Is the permit active? ® ❑ ❑ ❑ Signed copy of the Engineer's certification is in the Tile? ❑ ®❑ ❑ Signed copy of the Operation & Maintenance Agreement is in the file? ® ❑ ❑ ❑ Copy of the recorded deed restrictions is in the file? ❑ ❑ ® ❑ Comment: A copy of the designers certification could not be found in the file. SW Measures Yes No NA NE Are the SW measures constructed as per the approved plans? ❑ ❑ ❑ Are the inlets located per the approved plans? ❑ ❑ ❑ Are the outlet structures located per the approved plans? ® ❑ ❑ ❑ Comment: From aerial photos available online and photos provided by staff, the pond appears to be constructed. as reouired by the permit Other Permit Conditions Yes No NA NE Is the site compliant with other conditions of the permit? ® ❑ ❑ ❑ Comment: page: 2 Flowers Development Corporation 310 Friendly Road Morehead City, Carteret County, North Carolina STORMWATER PERMIT NARRATIVE Introduction and Existing Conditions THIS IS THE REVISED NARRATIVE AT THE RAISED SHWT/PERM.POOL This narrative discusses the stormwater permit application for the Flowers Development Corporation project. The site plan proposes construction of a 3.89 acre commercial site with 69% impervious surface coverage or 1 ] 7,333 sq-ft. This includes 30,150 sqft of proposed mini storage facilities, 13,200 sqft existing ministorage buildings, 33,030 sqft of proposed parking and driveway, and 40,953 sqft of existing parking and driveway,. The site is located at 310 Friendly Road, off Bridges Street, Morehead City, in Carteret County, North Carolina. The northerly and easterly adjacent parcels are currently wooded and vacant. The southerly adjacent parcel is ministorage site. The plan is for construction of a slab on -grade, metal -storage buildings and office, finish floor elevations vary at approximately 18.5 feet. The 3.89 acre is zoned commercial. The owner and operator of the facility is Mr. Richard Flowers, president of Flowers Development Corporation. In general, the parcel drains over a minimal grade across site towards an existing ditch along Friendly Road. As seen on the included location and topo map, the ditch and the site drains to an unclassified existing ditch, then over one half mile to Peletier Creek, a tributary of the Bogue Sound, classified as a SB water. STORMWATER MANAGEMENT As seen on the attached drawings, stormwater is being stored and treated by a forebay and wet detention pond. All impervious surfaces (parking area and roof drains) will drain overland flow to forebay. Run- off sediment will settle out in the forebay and run-off will flow across and through the weir across and into the main pool- The required 1-year event will draw down over 63 hours, out falling to an existing ditch along Friendly Road. Temporary storage peak elevation for the one year event is 18.01 feet. RECEIVED JUL 1 3 2012 BY: �71.BA$�llBIItt(IQill1.6©191 tif �, ass MCCOTTEs sLVD, HAVELOCK. NO 28532 2 5 2 - 4 4 4 - 5 7 65 ,25 2- 3 4 9 - 5 8 0 3 Flowers Development Corporation 310 Friendly Road Morehead City, Carteret County, North Carolina MAJOR DESIGN ELEMENTS • 69%, Impervious, Coastal SA/DA = 5.43 Ave depth Reqd 4.5 • Ave.Depth Provided= 4.50 feet • Total site area= 169,448 sqft • Impervious surfaces=117,333 sq.ft • Permanent Pool area reqd = 9201 sq.ft • Permanent Pool area provided = 9206 sq.ft • Required storage = 14259 cu.ft. • Provided storage = 15247 cu.ft. • Design storm draw down = 63 hours • BMP within recorded easement CONCLUSION Supporting Documentation Spreadsheet Plan set-Sht.SW-1 and spreadsheet Spreadsheet Plan set-Sht.SW-1 and spreadsheet Spreadsheet Spreadsheet Wet Detention supplement and spreadsheet Wet Detention supplement and spreadsheet Routing Plan set-Shts.SW-land 2 The proposed design is for 3.9 total acre site, including 117,333 sqft of proposed and existing building and parking impervious surfaces. All run off will drain to the forebay and wet detention facility. The forebay and pond are sized to contain the required event, draw down, freeboard, meeting or exceeding all DENR size, depth and volume requirements. 6Z1111 dy'W' ", W- Susan Sayger,PE ciF ED JUL 13 ZGQ I.enalneerinoftmail.com 388 M 9 C 0 T T I R 8 1 V 0 HAVIL00N N9 28532 2 5 2 - 4 4 4 - 5 7 6 5 , 2 5 2 - 3 4 9 - 5 8 0 3 Date: 1/1/2012 and March 2012,June 2012,july 2012 ProjeCt Flowers Facility wetoond Impervo % Area - POST Drainage Area-sq us Area impery bidgs- Area-bldgs Area -streets- Pervious Drainage area number ft Drainage Area-Ac _sq ft' ious Sq ft Area- streetsSgFt Ac Ac Area -Ac one 1 169448 Site Parameters 539016 3.VV 11 r333 u.OH 11 1333 369568 0 2.69 0.00 1.20 52115 I Pervi Impervo % Area- ous PRE Drainage Area-sq us Area impery bldgs- Area-bldgs Area -streets- Pervious Area - Drainage area number ft Drainage Area-Ac _sq ft' ious Sq ft Area- streetsSgFt Ac I Ac Area -Ac Sq.Ft. 1RQAAA J.0v l l /333 u.OU 1l rJ33 3 RA 11714,411 n RQ 117gT; u.uv dIals 1,zV z.rt-uul n n nn 9 R9 1 9n width % from @top width length impervi table perm length @length @top @length FULL DEVELOPMENT temp pool depth perm pool depth ous salda pool perm pool TEMP pool TEMP pool event storm Design Requirements Permanent pool__ — — 11733�3 Impervious(sq ft) 3,589990817'Total area area ACRES 0,6921 % da impervious 9201 REOD surface area SO FT=saida110o'contributin area _ 9208'iPROV surface area Sq Ft temp storage 0.673198267 rv=.05+.009(%impervlous) 14259 READ volume= rv•drainageil2) 15247 PRVD volume cf ft Percent TSS removal 90% Ave Depth 4.50 ave depth TEMP POOL SURFACE AREA PERM POOL SURFACE AREA BOTTOM 10' SHELF SURFACE AREA 75.3333333 1,818182 12514 SOFT SURFACE AREA AT BOTTOM OF POND 9206 SOFT 7312 SOFT 1.746556474 1867 SOFT RECEIVED JUL ZD12 RECEI 70D Jul 1 3 201Z BY: SMJ • 1c., 388 McCotterBlvd, Havelock, Date: 111/2012 and March 2012,June 2012 juty 2012 Project Flowers Facility wet pond PERM AND TEMP VOLUME ELEV LENGTH WIDTH UrLIA ELEV AREA INCREMNTAL VOLUME CUMMULATNE VOLUME PROVIDED PERMANENT POOL VOL PROVIDED TEMP POOL VOL REOD TEMP POOL VOL PROVIDED I PERMANENT POOL AREA REOD PERMANEN T POOL AREA 18.1 Freeboard 145.8 91,3—_, 13293 - 3228 16473 -Y44 ----17.85 -- --- -- - -- TEMP.POOLELEV— - � --� ----- - -- 142.89--'.-- l --__. .. --87,7 �82,8 �0,25 ...- 0-85-- 12514 10121 T �5128_ ....._ � 1_524_7 - - -- —T 15247 7 _ 138.8 0.50 11300 - 5128 - - - - - -- 185 PERM POOL ELEV -- - 128.8� _ W 72.6 0.50 - -9208_ 4129 -- 32854 y - - 32854" — - - — _ -18 - 116.8 _ 62A 0.50 7312 3524 28724 15.5 113.8 596 1.00 6782 0280 26201 14.5 107,6 53.8 4.95 5778 18021 10921 top sad, Storage__ -- •- ---- 78.1_ __.-._.. .23,9 _1867 _ A_ 15247 32854 15247 14250 0 tFREFI �,- - -- -(CUP) - - - - _.l __ ,.(Cu FI) _ 1_ _ (Cu ft}___ - I. _ _..{(IU St)--'i-(Sp Ft)-1 --.(Sq 1). _...1 I5q FI) I FOREBAY AEG FOREBAY VOL PROVIDED FOREBAY VOL INCREMNTAL CUMMULATIVE CLEANOUT DELTA ELEV 6914 6040 ELEV AREA VOLUME VOLUME VOLUME 18,5 0 CLEANOUT 1 05 4 •395 04 ELEV 18 0,5 2237 1043 4645 _ - 15.5 1 1938 1654 3602 14,5 1 1372 1115 1948 13.5 1 858 631 633 12.5 1 404 202 202 51 L#%� - 11.5 - _ - — -�- - - - --- 0,97908 i+ CLEANOUT VOLUME 5914 5913,669285 a -Avma yyolvw, v1 1 Q ;zu C� �c.� d��W�4_ Date: 111/2012 and March 2012,June 2012,july 2012 Project Flowers Facility wet pond ORIFICE CALCULATIONS volume q= Ca(2gh)^.5 diameter area Permanent Pool Elevation Orifice Centerline Temp Pool Elevation c h q= Ca(2gh)^.5 Time to drawdown 14/259 f 2 irV 0.02181'�6 W2 16.5 16.625 17.85 0.6 0.408333333 feet 0.067125724 cfs 212422.2905 sec 3540.371508 min 59:006..tO ours �2.45859132 days z • e• 3132A ri i� �•. y,••r.rrr ••J ✓r• � A I. PROJECT INFORMATION . Project Name Flowers Development Corp. Storage Building Contact Person Cass Flowers Phone Number 252-241.2310 Date 3C12l2011 Drainage Area I Lot Number 169,884 square feet Lot Owner's Signature 061 re_"rd II. DESIGN INFORMATION Soils Report Summary Soil type Seabrook Series Infiltration tale 0.65 inlhr OK SHWT elevation 3,00 fmsl Credit Calculation- Enter an Y in the appropriate cell below Man ed Grass Factor: Permeable concrete without a gravel base Permeable concrete with at least 6' gravel base X 0.6 " Flexible pavements with at least 4' gravel base Flexible pavements with at least 7' gravel base Bottom elevlion of the permeable pavement cross-section 1600 fmsl OK SA of permeable pavement being proposed 6,G85.00 ft' Resulting BUA counted as impervious 2,434.00 fig Additional Information Slope of soil subgrade at bottorn of permeable pavement 0.40 % OK Slope of the permeable pavement surface 0.40 % OK Construction sequence minimizes compaction to soils? Y YM OK Traffic volume (vehicles per day) 4,00 vlday OK Washed stone is specified for the gravel layer (if used)? Y WN OK, Concetrated flow from roofs 8 other surfaces directed away? Y Y1N OK Additional Information for Residential Lots Only +.. Total BUA allocated to this lot s� —8k 56— fi? Remaining lot BUA available fiz o be completed by pgrmfttee I HOA: n - Application Approved Application Rejected Reason for rejecting application: Signature of permittee t HOA: Date Farm SW40 I -Permeable Pavement-Rev.2.02Aug2010 RECEIVED APQ 18 7011 DWQ PROD # Parts I. & 11. Design Summary, Page i or 1 Permit No. (to be provided by DWQ) AA STORMWATER MANAGEMENT PERMIT APPLICATION FORM y �aF W n T FRO Y `f NCDENR 401 CERTIFICATION APPLICATION FORM PERMEABLE PAVEMENT SUPPLEMENT This form must be filled out printed and submitted. The Required Items Checklist (Part Ill) must be printed, filled out and submitted along with all of the required information. I. PROJECT INFORMATION Project Name Flowers development Personal Storage Contact Person Richard C. Flowers Phone Number 252-241-2310 Date 312812011 - Drainage Area I Lot Number 1Y84: F+Z . Lot Owner's Signature Soils Report Summary Soil type Infiltration rate Sli elevation Credit Calculation- Enter an "x" in the appropriate cell below Permeable concrete without a gravel base Permeable concrete with at least 6" gravel base Flexible pavements with at least 4" gravel base Flexible pavements with at least 7" gravel base Bottom elevtion of the permeable pavement cross-section SA of permeable pavement being proposed Resulting BUA counted as impervious Additional Information Slope of soil subgrade at bottom of permeable pavement Slope of the permeable pavement surface Construction sequence minimizes compaction to soils? Traffic volume (vehicles per day) Washed stone is specified for the gravel layer (if used)? Concetrated Flow from roofs & other surfaces directed away? Additional Information for Residential Lots Only Total BUA aliocated to this lot Remaining lot BUA available in/hr fms€ X fmsl ft2 ft2 Y YIN OK 4,00 v/day OK Y1N Y1N ft 2 ft2 Application Approved Application Rejected Reason for rejecting application: Signature of permittee t HOA: Date Managed Grass Factor: 0.6 Form SW401-Permeable Pavement-Rev.2-02Aug2010 Parts I. & Il. Design Summary, Page 1 of 1 Permit Number: (to be provided by DWQ) Drainage Area / Lot Number: Permeable Pavement 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. Important operation and maintenance procedures: — Stable groundcover will be maintained in the drainage area to reduce the sediment load to the permeable pavement. — The area around the perimeter of the permeable pavement will be stabilized and mowed, with clippings removed. — Any weeds that grow in the permeable pavement will be sprayed with pesticide immediately. Weeds will not be pulled, since this could damage the fill media. — Once a year, the permeable pavement surface will be vacuum swept. — At no time shall wet sweeping (moistening followed by sweeping) be allowed as a means of maintenance. — There shall be no repair or treatment of Permeable Pavement surfaces with other types of pavement surfaces. All repairs to Permeable Pavement surfaces must be accomplished utilizing permeable pavement which meets the original pavement specifications. — Concentrated runoff from roof drains, piping, swales or other point sources. directly onto the permeable pavement surface shall not be allowed. These areas must be diverted away from the permeable pavement. Initial Inspection. Permeable Pavements shall be inspected monthly for the��threee ` 6 0 months for the following: BMP element: Potentialproblem: How to remediate theproblem: The perimeter of Areas of bare soil and/or In the event that rutting or failure of the groundcover the permeable erosive gullies have occurs, the eroded area shall be repaired immediately pavement formed. and permanent groundcover re-established. Appropriate temporary Erosion Control measures (such as silt fence) shall be installed in the affected area during the establishment of permanent groundcover, and any impacted area of permeable pavement is to be cleaned via vacuum sweeping. The surface of the Rutting / uneven This indicates inadequate compaction of the pavement permeable settlement base / sub -base. If rutting or uneven settlement on the pavement order of/z inch or greater occurs, permeable pavement shall be removed and base / sub -base re -compacted, smoothed, and permeable pavement shall then be re- installed. Base and sub -base compaction shall be monitored by a licensed geotechnical engineer to ensure that infiltration capacity of base and sub -base are not compromised by compaction and smoothing processes. The pavement does not Vacuum sweep the pavement. If the pavement still dewater between storms, does not dewater, consult a professional. or water is running off. TV\ Form SW401-Permeable Pavement O&M-Rev.3 Page 1 of Permit Number: (to be provided by DWQ) Drainage Area / Lot Number: The permeable pavement will be inspected once a quarter 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 will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: How to remediate the roblem: The perimeter of the Areas of bare soil and/or erosive Regrade the soil if necessary to remove permeable pavement gullies have formed. the gully, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. Vegetation is too short or too Maintain vegetation at a height of 3 to 6 long. inches (remove clippings). The surface of the Trash/debris is present. Remove the trash/debris. permeable pavement Weeds are growing on the Do not pull the weeds (may pull out surface of the permeable media as well). Spray them with pavement. pesticide. Sediment is present on the Vacuum sweep the pavement. surface. The structure is deteriorating or Consult an appropriate professional. damaged. Damaged areas of the pavement shall be removed and repaired. The pavement does not dewater Vacuum sweep the pavement. [f the between storms. pavement still does not dewater, consult a professional. Permanently clogged pavement shall be removed and repaired. MAR 3 4 Z011 Form SW401-Permeable Pavement O&M-Rev.3 Page 2 of 3 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 name:Flowers Development Corporation Storage Building, BMP drainage area or lot number:) 10 Friendly Road. Morehead City, N. C. 4 Print name:Richard C. Flowers Title: President Address:200 East Fort Macon Road Atlantic Beach, North Carolina 28512 Phone: Signatt Date: s Z q — ZD % 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. 1, a Notary Public for the State of County of �� �— do hereby certify that rIQ CX personally appeared before me this day of \ , ' al , and acknowledge the due execution of the forgoing permeable pavement maintenance requirements. Witness my hand and official seal, -r, 4OTA r � L Olu r � w MAR 3 0 2011 My commission expires .-sV. Form 5W401-Permeable Pavement O&M-Rev.3 Page 3 of 4 03. C00031f� r 370 340 _ . - . _ - .. • _ _ - - Loin ss -- - - °°awl �Qo CUQU2 t7 , 190A 1941 ' - CU003i0.' �tf Ln rA a .is 1:163 feet RECEIVtD APR 18 2011 DWQ PROd # _- i 86 The A or AP horizon has hue of 10YR or 2.5Y, value of 2 to 4, and chroma of 1 or 2; or it is neutral and has value Of 2 to 4. The Btg horizon has hue of t OYR or 2.5Y, value of 4 to 7, and chroma of 1 or 2; or it is neutral and has value of 4 to 7. This horizon is sandy clay loam or clay loam. The Cg horizon has hue of 1 OYR, value of 5 to 7, and chroma of 1; or it is neutral and has value of 5 to 7. It is sandy, loamy, or clayey sediment. Roanoke Series The Roanoke series consists of poorly drained soils on stream and law marine terraces. These soils formed in fine textured sediment. Slope is less than 2 percent. Typical pedon of Roanoke loam; 4.3 miles east of Harlowe on North Carolina Highway 101, 0.6 mile north on State Road 1161, and 200 feet north of the road: A-0 to 8 inches; black (10YR 211) loam; moderate medium granular structure; very friable; many fine, medium, and coarse roots; very strongly acid; clear smooth boundary. BEg-8 to 13 inches; gray (10YR 5/1) clay loam; few fine distinct yellowish brown (10YR 5/8) mottles; moderate medium subangular blocky structure; friable, slightly sticky and slightly plastic; common fine roots; common fine pores; very strongly acid. - clear wavy boundary. Btg-13 to 51 inches; gray (10YR 5/ 1) clay; common medium distinct brownish yellow (10YR 6/6) and yellowish brown (10YR 5/8) mottles; moderate medium angular blocky structure; firm, sticky and plastic; few fine roots; few fine pores; many distinct day films on faces of peds; very strongly acid; abrupt wavy boundary. BCg-51 to 58 inches; gray (1 OYR 6/ 1) sandy clay loam; many medium distinct brownish yellow (10YR 6/6) mottles; massive; friable, slightly sticky and slightly plastic; very strongly acid; gradual wavy boundary. Cg-58 to 80 inches; gray (1 OYR 5/1) fine sandy loam; common medium distinct fight yellowish brown (10YR 6/4) mottles; massive; very friable; common thin lenses of clay; strongly acid. Soil Seabrook Series The Seabrook series consists of moderately well drained soils on stream and low madhe terraces. Th soils formed in coarse textured sediment. Slope is 0 percent. Typical pedon of Seabrook fine sand; 3 miles norl Cape Carteret on North Carolina Highway 58. 0.75 a north on State Road 1109. 1.3 miles west on State F 1106. 0.5 mile south on a farm path, and 20 feet em the path: Ap—O to 8 inches; dark grayish brown (10YR 4/2) 1 sand; single grained; loose; common fine roots, slightly acid; abrupt smooth boundary. C1-8 to 24 inches; light yellowish brown (10YR 61A fine sand; few medium faint yellowish brown (f( 6/8) mottles; single grained; loose; few fine roo medium acid; gradual wavy boundary. C2---24 to 48 inches; very pale brown (10YR 714) lim sand; common medium faint light gray (10YR 7j and yellowish brown (10YR 5/8) mottles; single grained; loose; medium acid; gradual wavy boundary. Cg--48 to 80 inches; light gray (10YR 7/2) sand; common medium faint very pale brown (10YR 7 mottles; single grained; loose; medium acid. Seabrook soils are sandy to a depth of 80 inches more. Reaction ranges from very strongly acid to sfj acid unless lime has been added. Few or common ; concretions are in some pedons. The A horizon has hue of 10YR, value of 3 to 5. E chroma of 2 or 3. The C horizon has hue of 1OYR or 2.5Y, value of, 7, and chroma of 3 to 8. The Cg horizon has hue off 10YR or 2.5Y, value of 6 or 7, and chroma of 1 or 2 Mottle9-or base colors that have chroma of 1 of 2 a within 40 inches of the surface: The C and Cg horin are sand, loamy sand, loamy fine sand, or fine sand State Series . - The State series consists of well drained soils on stream and low marine terraces. These soils formaE The A and B horizons are 40 to 60 inches thick. moderately fine textured sediment. Slope ranges fro Reaction ranges from extremely acid to strongly acid to 2 percent. unless time has been added. Typical pedon of State loamy fine sand, 0 to 2 pe The A or A.p horizon has hue of, 1OYR or 2.5Y, value slopes; 2.3 miles southeast of Harlowe on North Co of 2 to 4, and chroma of 1 or 2; or it is neutral and has Highway 101 to State Road 1160. 0.8 mile east to t value o1 2 to 4. It is less than 10 inches thick. Road 1158, 1.4 miles south on State Road 1158, a The Btg horizon has hue of 10YR to 5Y, value of 5 to mile west on.a farm path, and 30 feet south of the 7, and d chroma of 1 or 2; or it is neutral and has value of 5 to 7. This horizon is clay, silty clay, or clay loam. Ap--O to 7 inches; brown (10YR 5/3) loamy fine sa The Cg horizon has colors similar to those of the 13tg weak medium granular structure; very friable, horizon and can have hue of 5GY, value of 5 or 6, and common fine roots; medium acid; abrupt smooi chroma of 1. It is sandy, loamy, or clayey C F-Al IVED APR 18 2011 DWQ PROJ # ::mteret County, Forth Carolina coodland use and management. Areas managed for oblolly pine benefit from ditching and bedding. Fertilizer s also used in many plantations. In cultivated areas, the principal crops are corn and Soybeans. Wetness is the main limitation. Drainage systems include land grading for surface drainage, open >fthes, and tile. Common pasture forages include tall fescue and Ladino clover. Seasonal wetness limits the use of this soil for building site development, sanitary facilities, and recreation. rlowever, some areas have been developed by using ntensive drainage systems that include open ditches and file and land grading for surface drainage - This Rains soil is in capability subclass Illw (drained) a IVw (undrained). It is in woodland group 10W. Ro—Roanoke loam. This soil is nearly level and poorly drained. It is on broad flats and in depressions on stream and low marine terraces mainly in the north - central and east -central parts of the. county. Mapped areas are irregular in shape and range from 10 to 500 acres. TWcafly, the surface layer is black loam 8 inches Mick. The subsoil extends to a depth of 58 inchm it is gay day loam in the upper part gray clay in the middle part, and gray sandy clay loam in the lower part. The underlying material to a depth of 80 inches is gray fine sandy loam. Permeability is slow, and the shrink -swell potential is moderate. The soil ranges from extremely acid to strongly acid unless lime has been added. The seasonal Ir h water table is at or near the surface. Water ponds in aepressions for brief periods_ The soil is subject to rare boding in low -tying areas. Included with this soil in mapping are small areas of the poorly drained Tomotley soils. Also included are a tew areas of a somewhat poorly drained, clayey soil in sightly higher areas than Roanoke soil and a very poorly ar-ained, clayey soil in depressions. The included soils Brake up about 10 to 20 percent of this map unit. This Roanoke soil is used mainly as woodland. In a flew areas, it is used as pasture or cropland. In woodland areas, loblolly pine, pond pine, blackgum, sweetgum, water oak, swamp chestnut oak, red maple, fellow -poplar, and willow oak are dominant. The understory includes redbay, sweetbay, American holly, s& tchcane, sweet pepperbush, greenbrier, waxmyrUe, miler gailberry, large gallberry, fetterbush, honeysuckle, blueberry, huckleberry, poison4vy, sweetleaf, grape, Virginia chainfern, cinnamon fern, Virginia creeper, and Carolina jessamine. Wetness is the main limitation. Logging when this soil is wet causes deep ruts, compaction. poor surface drainage, and lower productivity. Areas managed'for loblolly pine are generally ditched and bedded_ Fertilizer is also being ised in some plantations. In cultivated areas, corn and soybeans are the-r crops. Wetness is a major limitation. The slowty permeable subsoil limits internal drainage, so land grading for surface drainage and open ditches are used. Tile is generally not used. Soil structure is destroyed and large Gods form if this soil is tiled when wet. This can also result in pending and a poor seedbed. Common pasture forages include tall fescue and Ladino clover. Roanoke soil is not commonly used for building site development, sanitary facilities, or recreation because of wetness, moderate shrink -swell potential, slow permeability, the clayey subsoil, and rare flooding of low- lying areas. This Roanoke soil is in capability subclass lllw (drained) or IVw (undrained). It is in woodland group 9W. Se —Seabrook fine sand. This soil is nearly level and moderately well drained. It is in slightly convex areas on stream and low marine terraces mainly in the southern part of the county along Bogue Sound and the White Oak River. Mapped areas are irregular in shape and range from 5 to 150 acres. ; Typically, the surface layer is dark grayish brown fine sand 8 inches thick. The underlying material extends to a depth of 80 inches. It is light yellowish brown fine sand in the upper part. In the middle part, it is very pale brown fine sand that has light gray mottles, and it is light gray sand in the lower part. Permeability is rapid, and the available water capacity is low. The soil ranges from very strongly add to slightly acid unless lime has been added. The seasonal high water table is 2 to 4 feet below the surface. This soil is subject to rare flooding in low -tying areas. Wind erosion is a hazard in areas not protected by vegetation. Included with this soil in mapping are small areas of Altavista, Augusta, Conetoe, Leon, and Wando soils. The moderately well drained Altavista soils, the somewhat poorly drained Augusta soils, and the poorly drained Leon soils &cur at random within the map unit with no apparent change in landscape. The well drained Wando and Conetoe soils are on low ridges. Some areas of wet soils in depressions are shown on the map with a special symbol. These areas are smaller than 4 acres. The included soils make up about 10 to 15 percent of this map unit This Seabrook soil is used mainly as woodland. In a few areas, it is used as pasture or cropland. In woodland areas, loblolly pine, longleaf pine, red maple, water oak, sweetgum, southern red oak, Shumard oak, blackgum, yellow -poplar, white oak, and willow oak are dominant. The understory includes blueberry, bitter gallberry, redbay, greenbrier, flowering dogwood, turkey oak, blackjack oak, waxmyrUe, sassafras, grape, sweetbay, Virginia creeper, sourwood, sweet pepperbush, and threeawn grass. Droughtiness between rains is the main concern in woodland use and management RECEIVED APR 18 2011 DWQ PR0,3 # -, ivApal 0 � o � o Aq r �Loo RA, FF= 18.0 "qN S f W=17.8. @WALK/PVMT=17.5 B" PVC LINE TO CAPTURE DOWNSPOUT RAINWATER- �?a 5 DOWNSPO T EACH-tS I D E 16. y FLOW ARMOURED OUTLET ' FLOW .y A 17.v 3 Wet Pond Use to Find Areas/Volumes if the Engineer Reports the Main Pond and Forebay Separately (This is not linked to other worksheets in this file.) Permanent Pool Basin Forebay Total Contour El (ft) SA (sf) Inc Vol (cf) Cum Vol (cf) Contour El (ft) SA (sf) Inc Vol (cf) Cum Vol Icf) Contour El (ft) SA (sf) Inc Vol (cf) Cum Vol (cf) 9.55 1,867 0 0 12.5 335 0 0 9.55 1,867 0 0 14.5 4,960 16,897 16,897 14.5 818 1,153 1,153 14.5 -5,778 18,921 18,921 15.5 5,387 5,174 22,070 15.5 1,395 1,107 2,260 15.5 6,7821 6,280 25,201 16.0 5,664 2,763 24,833 16.0 1,648 761 3,020 16.0 7,312 3,524 28,725 16.5 6,465 3,032 27,865 16.5 2,741 1,097 4,118 16.5 9,206 4,130 32,854 0 27,865 17,05 3,931 1,835 5,952 0.0 3,931 1,835 34,689 based on pond design w/ PP forebay elev higher than main pond PPE forebay % = 5,952 1 34,689 * 100 = 17.2% Does not meet the min req IF forebay elev was lowered to 16.5: forebay % = 4,118 / 32,854 * 100 = 12.5% Does not meet the min req based on Sue's design where the forebay vol above the PP still counts towards the PP and the TP forebay % = 5,952 / 32,854 * 100 = 18.1% Temporary Pool Basin Forebay *to exclude the higher PP in the forebay* Total Contour El (ft) SA (sf) Inc Vol (cf) Cum Vol (cf) Contour El (ft) SA (sf) Inc Vol (cf) Cum Vol (cf) Contour El (ft) SA (sf) Inc Vol (cf) Cum Vol (cf) 16.50 9,206 0 0 17.05 3,931 0 0 16.50 9,206 0 0 17.0 11,300 5,127 5,127 16.5 2,741 -1,835 -1,835 17.0 11,300 3,292 3,292 17.851 12,5141 10,1211 15,2471 -1,835 17.85 12,514 10,1211 13,4131 based on pond design w/ PP forebay elev higher than main pond PPE the temporary pool vol = 13,413 Does not meet the min req based on Sue's design where the forebay vol above the PP (16.5) counts towards both the PP and TP the temporary pool vol = 15,247 which does meet the min vol req MC®ENR North Carolina Department of Environment and Natural Resources Beverly Eaves Perdue Governor May 21, 2012 Mr. Richard. Flowers, President Flowers Development Corporation 212 Bayview Blvd. Atlantic Beach, NC 28512 Division of Water Quality Charles Wakild, P. E. Director Subject: Request for Additional Information Stormwater Project No. SW8 120114 Flowers Development Corporation Carteret County Dear Mr. Flowers: Dee Freeman Secretary The Wilmington Regional Office received and accepted a State Stormwater Management Permit Application for Flowers Development Corporation on January 31, 2012 with additional information received on April 9, 2012. A preliminary in-depth review of that information has determined that the application is not complete. The following information is needed to continue the stormwater review: i 1t. Seasonal High Water Table: Due to the concern with the seasonal high water table v determination for this project, the Division asked their soil scientist, Vincent Lewis, to evaluate the seasonal high water table in the location of the wet detention pond. Mr. Lewis visited the site on April 8, 2012 and determined the seasonal high water table to be less than 12 inches from the surface based on the soil characterization in the vicinity of the proposed pond. Additionally, he found saturated sand at a depth of 12 inches. Based on Mr. Lewis's site visit, it appears that the proposed permanent pool elevation will be more than 6" below the seasonal water table. In this case, additional calculations and analysis are required per Section 10.3.2 of the NC BMP manual. Please evaluate the pond based on this section of the manual, specifically Item 2 on page 10-9, in order to demonstrate the pond will function as intended. �// 2. Please detail how an average depth of 4.5 was determined. The wet detention pond supplement indicates that Option 2 was selected to determine the average depth. Using the equation provided in the NC BMP manual for Option 2, and the surface areas, elevations, and depths reported on the supplement, the calculated average depth is 4.17 ft, which is rounded down to 4.0 ft as follows: 10.25 x �1 + 7312)] + [(7312 2 2413) x (7312)J = 4.17 ft 3. The provided forebay volume, 5,535 ft3, appears to include the volume between elevations 11.25 and 15.56. a. Please begin the forebay volume calculation at 12.25. The sediment accumulation depth is not part of the provided volume.. b. With a forebay berm weir provided at the permanent pool elevation, 15.0 , the forebay volume can only be considered between elevations 12.25 and 15. If you wish to consider the forebay volume up to an elevation of 15.56, please remove the �� k�provided weir, revise the permanent pool elevation to 15.56 and revise the temporary N pool elevation as needed to provide a minimum of 14,259 cubic feet of storage c`volume above the new permanent pool elevation. Wilmington Regional Office 127 Cardinal Drive Extension, Wilmington, North Carolina 28405 One Phone: 910-796-72151 FAX: 910-350-20041 DENR Assistance: 1-877-623-6748 NorthCarohna Internet: www.ncwaterquality.org Naturally An Equal Opportun4ylAffirmative Action Employer Richard Flowers May 21, 2012 Stormwater Application No. SW8 120114 4. The inflow hydrograph from HydroCAD has been presented in support of the pond's drawdown time. This hydrograph appears to reflect the inflow to the pond, not the outflow. HydroCAD also provides a Stage -Discharge function, which can be used to demonstrate that the required storage volume, based on the 115" storm event, is drawn down time through the orifice,within the required 2-5 day timeframe. The Stage - Discharge function must start,at the temporary pool elevation under full head and end at the permanent pool elevation under no head. Another option for demonstrating the average drawdown time for the required storage volume through the selected orifice would be to use the standard orifice equation• available in Chapter 3-of the NC BMP-- manual, where the average head, h, is calculated as H13. /5. On page 3 of the wet detention pond operation & maintenance agreement (O&M), please revise the elevations reported in the text area prior to the basin diagram to reflect actual depths. For instance, for the main pond the depth would be 6.1 ft. 6. Please remember that a change to one number may have a domino effect on other numbers. Please check all plans, calculations and forms for consistency and make changes as needed. Please note that this request for additional information is in response to a preliminary review. The requested information should be received in this Office prior to June 11, 2012, or the application will be returned as incomplete. The return of a project will necessitate resubmittal of all required items, including the application fee. If you need additional time to submit the information, please mail, email or fax your request for a time extension to the Division at the address and fax number at the bottom of this letter. The request must indicate the date by which you expect to submit the required information. The Division is allowed 90 days from the receipt of a completed application to issue the permit. The construction of any impervious surfaces, other tFiari-a construction entrance under an approved Sedimentation Erosion Control Plan, is a violation of NCGS 143-215.1 and is subject to enforcement action pursuant to NCGS 143-215.6A. Please reference the State assigned project number on all correspondence. If you have any questions concerning this matter please feel free to call me at (910) 796-7215 or email me at christine.nelson@ncdenr.gov. Sincerely, CL�-� ?�" Christine Nelson Environmental Engineer GDS/can: S:IWQS1Stormwater\Permits & Projects120121120114 HD12012 05 add info 120114 cc: Sue Sayger, KSMJ Engineering Christine Nelson Wilmington Regional Office Stormwater File 41 Page 2of2 Richard Flowers February 28, 2012 Stormwater Application No. SW8 120114 February 28, 2012 Mr. Richard Flowers, President Flowers Development Corporation 212 Bayview Blvd. Atlantic Beach, NC 28512 Subject: Request for Additional Information Stormwater Project No. SW8 120114 Flowers Development Corporation Carteret County Dear Mr. Flowers: The Wilmington Regional Office received and accepted a State Stormwater Management Permit Application for Flowers Development Corporation on January 31, 2012. A preliminary in-depth review of that information has determined that the application is not complete. The following information is needed to continue the stormwater review: Soils Report: a. The soils report identifies that the groundwater table was encountered at an elevation of 15.1. Please note that the groundwater table is not the same thing as the seasonal high water table (SHWT). Please provide the elevation of the SHWT in the vicinity of the proposed pond. b. Soils reports are typically prepared by soil scientists or geotechnical engineer. Please either provide the soil classification qualifications of the engineer, Sue Sayger, who prepared the provided soil report or provide a soils report from a licensed soil scientist. 2. Please delineate the wet detention pond drainage area on the plans. 3. Please detail how an average depth of 4.5 was determined. The wet detention pond supplement indicates that option 1 was selected to determine the average depth. Using the provided permanent pool volume and surface area, the average depth according to option 1 should be 3.3 ft, or 3.5 ft once rounded. 4. It appears that the permanent pool volume, average depth, and associated calculations include the 1-foot sediment accumulation depth. The depth of the permanent pool is considered to be difference between the permanent pool elevation and the top elevation of the sediment storage and does not include the minimum 1-foot sediment accumulation depth (refer to Figure 10-2b and Section 10.3.4 of the NC BMP manual). Please revise the calculations, supplement, and other documentation to consider just the permanent pool above the sediment accumulation depth in the pond calculations. For instance, since the forebay is only 1 ft deep, the forebay would comprise entirely of the sediment storage and would not contribute any volume toward the permanent pool volume. It is required that the forebay contain approximately 20% of the permanent pool volume. Page 1 of 3 r " Richard Flowers February 28, 2012 Stormwater Application No. SW8 120114 5. The sediment clean outlremoval elevation (bottom of the permanent pool) is reported inconsistently in the application documents. For instance, the wet detention pond supplement identifies this elevation as 12.0 while the Operation & Maintenance Agreement (O&M) lists it as 9.9. Please present the information accurately and consistently throughout the documents. 6. Please do not round the SAIDA ratio to the tenth decimal place, instead this ratio should be rounded to the hundredth decimal place. This will help to reduce rounding errors, which may result in deficiencies. 7. On the wet detention pond supplement and in the calculations, the temporary pool elevation is identified at an elevation of 17.43 ft; however the next available outlet appears to be set at an elevation of 16.3. Since the temporary pool elevation is considered to be set at the next available outlet above the permanent pool, please list the temporary pool as the next available outlet and ensure that the information is consistent and accurate. & The drawdown rate for the temporary pool should be based on the design storm and required storage volume, not the actual storage volume. With the current orifice size of 3", the required storage volume will drawdown in less than two days. Please resize the orifice and provide calculations demonstrating that the drawdown rate for the required minimum storage volume is between 2 and 5 days. 9. Please provide Section III of the wet detention pond supplement, the Required Items Checklist. 10. Please ensure the elevations and depths listed on page 3 the wet pond O&M are consistent. For instance, the current pond design calls for the sediment removal elevation in the forebay to be 15 ft while the permanent pool elevation is 15 ft. In this scenario, the depth in the forebay is 0.0 ft. (please refer to item 3 of this letter for the issues surrounding the forebay design) 11. Please provide additional grading detail, especially along the edges of the property, to help demonstrate that the runoff from the impervious areas will be directed to the stormwater collection system and that no offsite area enters the pond drainage area. 12. The plans indicate that the pond discharge will be directed onto the property owned by Best Ventures LLC. Please demonstrate that there is an existing natural drainage channel that is on this property and either provide a letter from that property owner agreeing to the proposed discharge of water or demonstrate that there is a drainage easement for this discharge. 13. On plan sheet SW-2, please identify the sediment removal elevations of the pond. 14. If the top of the forebay weir is set at an elevation of 17 ft, please demonstrate how the forebay will return to a permanent pool elevation of 15 ft. One option is to propose a weir set at or just below the permanent pool elevation. Ideally this weir would be located to maximize the flow path. 15. Please increase the quantity of plants listed in the planting schedule. Section 10.3.7 of the NC BMP Manual requires a minimum of 50 plants per 200 sf of shelf area. 16. Please remember that a change to one number may have a domino effect on other numbers. Please check all plans, calculations and forms and make changes as needed. Page 2 of 3