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HomeMy WebLinkAboutSW7000718_COMPLIANCE_20120522NORTH CAROLINA Department of Environmental Qua STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. sw 706 %l k DOC TYPE ❑ CURRENT PERMIT ❑ APPROVED PLANS ❑ HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE YYYYM M DD NCDENR North Carolina Department of Environment and Natural Resources Division of Land Resources James D. Simons, PG, PE Director and State Geologist Land Quality Section May 22, 2012 Beverly Eaves Perdue, Governor Dee Freeman, Secretary NOTICE OF VIOLATIONS OF THE SEDIMENTATION POLLUTION CONTROL ACT CERTIFIED MAIL RECEIVED RETURN :RECEIPT REQUESTED 7011 0110 0000 9948 4317 MAY 2 2 2012, H/S New Bern Outnarcels, LLC Post Office Box 204227 Augusta, Georgia 30917 DWQ-WARO RE: Project Name: Twin Rivers Mall Stormwater Relocation Project ID: CRAVE-2012-010 Location: US Hwy 17 County: Craven River Basin: Neuse Last Approval Date: December 14, 2011 Dear Sir or Madam: On May 15, 2012, personnel of this office inspected a project located on the northwestern corner of the intesection of US Highway 17 and US Highway 70, in Craven County, North Carolina. This inspection was performed to determine compliance with the North Carolina Sedimentation Pollution Control Act (Act) of 1973, The inspection revealed a land -disturbing activity of approximately 11,4 acres being conducted. It is our understanding that you and/or your firm are responsible for this land -disturbing activity. The purpose of this letter is to inform you that this activity was found to be in violation of the Act, G. S. t 13A-50 to 66, Title 15A, North Carolina Administrative Code (NCAC), Chapter 4. If you feel that you are not responsible for the following violations, please notify this office immediately. The violations found are: a. Failure to conduct a land -disturbing activity in accordance with the approved erosion and sedimentation control plan. G.S. 113A-57(5). The inspection revealed that the approved erosion and sedimentation control plan has not been properly implemented -The approved "plan -indicates -the existing-stormwater pond will remain -in place -and _ functioning until all new construction is complete. Washington Regional Office 943 Washington Square Mall, Washington, North Carolina 27889 Phone:252-946-64811 Fax 252-975-3716 Internet hth7lportal.ncdenr.org/webAnland-quality An Equal Opportunity/Affirmative Action Employer -50%recycled/10% Post Consumer Paper Certified Mail H/S New Bern Outparcels, LLC ATTK Mr. John Gibson, Managing Partner May 22, 2012 Page 2 b. Failure when a land -disturbing activity that will disturb more than one acre is undertaken on a tract, to install sedimentation and erosion control devices sufficient to retain the sediment generated by the land -disturbing activity within the boundaries ofthe tract during construction upon and development of the tract. G.S. 113A-57(3). Ve ` A C. Failure o takee alRre sonable measures to protect all public and private property from damage by such land -disturbing activities. 15A NCAC 4B.0105. r,7r � c d. Failure to msall'and maintain all temporary and permanent erosion and sedimentation control �� there undyer,(dbrm� brafter the development of a site. 15A NCAC 4B.0113. The inspection revealed that adequate and appropriate erosion and sedimentation control measures have not been installed in critical areas throughout the site, which has resulted -ink sediment leaving the site through the triple culverts under Hwy 70.E To correct these violations, you must, WITHIN 15 DAYS OF RECEIPT OF THIS NOTICE OF VIOLATIONS: Cease filling-the=existingstormwater pond until -all new construction is complete as indicated ,on -the plan approved by this office on December 14, 2011 2. In accordance with the approved plan properly install, reinstall, and/or maintain erosion and sedimentation control measures and/or devices throughout the site sufficient to retain sediment from entering a -natural watercourse or other -properties., The violations cited herein may be referred to the Director of the Division of Land Resources (Director) for appropriate enforcement action, including civil penalty assessments for an initial one - day violation and/or a continuing violation. The penalty for an initial one -day violation may be assessed in an amount not to exceed $5,000.00. The Division of Land Resources is not required to provide a time period for compliance before assessing an initial penalty for the violations cited herein. Please be advised that a civil penalty may be assessed for the initial day of violations regardless of whether the violations are corrected within the time period set out below. In addition, if the violations cited herein are not corrected WITHIN 15 DAYS OF RECEIPT OF THIS NOTICE OF VIOLATIONS this office may request that the Director take appropriate legal action against you for continuing violations pursuant to NCGS I I3A-61.1 and 113A-64. A penalty may be assessed from the date of the violation, pursuant to NCGS 113A-64(a)(1), and for each day of a continuing violation in an amount not to exceed $5,000.00 per day. Please be advised that any new land -disturbing activity associated with this project should not begin until the area presently disturbed is brought into compliance with the Act. When corrective actions Certified Mail WS New Bern Outparcels, LLC ATTN: Mr. John Gibson, Managing Partner May 22, 2012 Page 3 are complete, you should notify this office so that work can be inspected. You should not assume that the project is in compliance with the Act until we have notified you. After installation, all erosion control measures must be maintained in proper working order until the site is completely stabilized. We solicit your cooperation, and would like to avoid taking further enforcement action. At the same time, it is your responsibility to understand and comply with the requirements of the Act. Copies of the relevant statute and administrative rules may be examined at this office or will be sent to you upon request. Should you have questions concerning this notice or the requirements of the Act please contact either Allison Ward or me at your earliest convenience. Patrick H. McClain, PE Regional Engineer PHM:aw Enclosures: Sedimentation Inspection Report cc: Mr. Gray Hauser, PE, State Sedimentation Specialist Mr. Alton Hodge, Regional Water Quality Supervisor Mr. Roy Brownlow, Division of Coastal Management — Morehead LQ Files �0 c wnrE,go` ®� /� North Carolina Division of Water Quality oNPDES Stormwater Discharge Permit NCDLEN.,R for Construction Activities Cuver Sheet lur NC0010000 noZod Auqual 2, 2011 What is this permit? This is your General Stormwater Permit for Construction Activities, developed to meet federal National Pollutant Discharge Elimination System (NPDES) requirements. It is separate from your Erosion and Sedimentation Control (E&SC) Plan, which has been a North Carolina requirement for over 35 years. Federal regulations adopted by the U.S. Environmental Protection Agency (EPA) and North Carolina Division of Water Quality (DWO) require an NPDES permit for your project. The EPA has delegated DWO authority to administer the NPDES program in North Carolina. Two divisions of the Department of Environment and Natural Resources are responsible for different parts of the federal permitting requirements. They E&SC plan approved by'the Division of Land Resources (or a delegated local program) contains the core erosion control requirements for your project. The. NPDES General Permit issued by DWO contains additional requirements related to a broader range of water quality issues. These permits are related, but separate. Both contain conditions your project site must meet. What,does this permit require me to do? You should read and become familiar with the provisions of this permit. Below is a list of the major requirements, with indications where those differ from the previous Construction General Permit. EROSION AND SEDIMENT CONTROL PLAN You must implement the Erosion and Sedimentation Control Plan approved for your project by the Division of Land Resources or by an approved local program. Adherence to that E&SC Plan is an enforceable component of the Stormwater Permit. Are there new requirements in this permit? This General Permit reflects changes made in the federal regulations effective February 1, 2010, that regulate discharges from construction sites. The federal regulations resulted from litigation decisions that mandated construction activities over a certain size must contain additional specifications to reduce the amount of wastes and sediment loading that reach the nation's waters. The Division of Water Quality and the Division of Land Resources established the Construction General Permit Technical Advisory Group (CTAG) to guide the development of this NPDES permit. A draft permit was available for public review in May 2011, and the final permit became effective on August 3, 2011. The most notable change in the new permit is a requirement that ground, stabilization, such as wheat straw application, be applied within 14 days from the last land -disturbing activity. For steep slopes, that area must be stabilized within 7 days. Please see page 2 of this document for details. Your E&SC plan will identify areas where the more stringent 7 and 14 day ground stabilization requirements apply. See "New Ground Stabilization Requirements" on page 2. MONITORING & INSPECTIONS ► You must keep a rain gauge on site. ► Dedicated demolition and other waste areas and earthen material stockpiles must be located at least 50' from storm drains or streams unless no alternative is feasible (new requirement). ► You must inspect all E&SC measures at least once a week and within 24 hours after any storm event greater than a half inch (during a 24-hour period). You must take immediate corrective action for any device failure. ► You must inspect all outlets where stormwaier runoff leaves your site and evaluate the effect on nearby streams or wetlands. Corrective action must be taken if sediment is deposited off site or into a stream or wetland, or causes a visible increase in turbidity (cloudiness) of any waterbody. (0ontinued an reverse side) u NPDES Stormwater Discharge Permit for Construction Activities _ . _ Revised August 2, 2011 Permit Requirements (mminued) ► You must keep records of these inspections and any corrective actions taken. OPERATION & MAINTENANCE You must provide the operation and maintenance necessary to maintain optimal performance of stormwater controls. This means take corrective action if erosion and sediment control facilities are not operating property! Operation and maintenance includes, but is not limited to: • Regularly cleaning out sedimentation basins. • Stabilizing eroded banks or spillway structures. Repairing/clearing out inlets and outlets. • Repairing piping, seepage and mechanical damage. Repairing silt fence damage. Regular inspections are a chance to check impacts to nearby waters. If you observe sediment that has deposited in a stream or wetland, you must notify the Division of Water Quality regional office within 24 hours and provide written notice within 5 days (see # 3 on page 6 of the General Permit). Please send a copy of this correspondence to the Division of Land Resources (DLR). NON-COMPLIANCE & FINES Take compliance seriously! Projects that violate Stormwater Permit conditions and/or have unauthorized water quality impacts are subject to fines. Civil penalties of up to $25,000.00 per day for each violation may be assessed. Who inspects me for what? DWO coordinates with DLR's Land Quality Section to ensure compliance with state rules and regulations governing construction activities. That means your project is subject to enforcement by both divisions. In general, Land Quality staff will inspect your site on a regular basis. DWQ staff may also do inspections. The inspections may be routine in nature, or, the result of public complaints. Do 1 need to submit a Notice of Intent to have coverage under this permit? No. Once your EBSC Plan is approved, your site is automatically covered under this permit. You do not need to submit a Notice of Intent for a Certificate of Coverage. NEW STABILIZATION:TIMEFRAMES Site Area Description Stabilization Timeframe Exceptions OPerimeter dikes, swales, ditches and slopes 7 days None High Quality Water (HOW) Zones 7 days None Slopes steeper than 3:1 7 days If slopes are 10' or less in length and are not steeper than 2:1, 14 days are allowed. p Slopes 3:1 or flatter 14 days 7 days for slopes greater than 50' in length. r, All other areas with slopes flatter than 4:1 14 days None, except for perimeters and HOW Zones. Do you need more information? w�t�,gpG NC Stormwater Permilling htt2//porlal.ncdenr.ora/web/wg/ws/su o2oF y�C NCGO1 Permit Information httpl/portal.ncdenr.org/web/watws/su/construction Map of Regional Offices httpl/portal.ncdenr.org/web/wg/home Still have questions? Call the DWO Regional Office nearest your project's location: Asheville 011ice (828) 296-4500 Washington Office (252) 946-6481 Fayetteville Office (910) 433-3300 Wilmington Office (910) 796-7215 Mooresville Olfice (704) 663-1699 Winston-Salem Office (336) 771-5000 Raleigh Office (919) 791-4200 Central Office (919) 807-6300 Samir From: Vinson, Scott Sent: Thursday, March 01, 2012 3:44 PM To: smitchell@geminiconstructionco.com Cc: Dumpor, Samir Subject: Twin Rivers Mall Stormwater modification Steve, Samir will be out of the office until Monday, but we wanted to go ahead and let you know that the Division is good with your proposal and that the only thing we would like added would be the implementation of sediment bags to be used during the pumping process to help control turbidity and stay below 50 NTU's as required under the State's turbidity standards. This will require some self sampling collection & monitoring on your part to help determine what level of turbidity is being pumped out. There are local environmental companies that could help the on -site contractors determine the levels as they pump both the pond & any future stormwater out. You should keep records of these results as well and any additional steps they may need to take to get turbidity levels down below 50 NTUs if they ever go above. Also, if you could please send updates (emails) as to the start/completion of each of the major steps outlined within the construction proposal. Please call or write if you have any questions. Thanks, Scott SCOTT VINSON NCDENR-DWQ 943 WASHINGTON SQUARE MALL WASHINGTON, NC 27889 OFFICE:(252) 946-6481 DIRECT:(252) 94&3848 Before printing this email, please consider your budget and the environment. "E-mail correspondence to and from this address is subject to the North Carolina Public Records Law and may be disclosed to third parties unless the content is exempt by statute or other regulation. ILI,bore, Ur rr)Unmi 12 to it I p: •11r'.-, r, -hpc: v A• In IOU' .1 'I'll, Snt,G L,Rlfjr 4C.q f1, ol(i :LDU11, !, •1'19r,, r: Ir ,n!,!•.•, !g jis A'Jy;l r,: inrv'. h vJ r. („W,Ilr.""I ps JA VCf)v_1,1B r1p/It i ,!• '01 1 Along y, h1V I11U {1G CDII?Ii.007lf li i•:VUO: 11 f;lby?6co!Olt,dl(G q AO'1',6%r 9UA ,"1(1S111OU2' 11. up, 4j)OA:" jm, :E Ano CJill(I h .::4n x-iti s-&g9(4e iriugH.'.f zfu (!L. 2'"L!'\JUUI(J if j'Gli 0.. .4i4I V; iJ!,,'U910L LE!r I"4"A' U11 4:1Lj 91JA ^,. PIIl'O1:31 2(69? `poh Up" 4.,•, Q 10 rUp ) 10 . q JmgC;ljA lent,!,, yOl:'a' j yox 7p MIQ2 I(gmA C,f it O'•.! i:.,(.S. qu* qm j6`.Gp s; just briub paw (U` wu 4 :i 9L'", tritfiu �tOl.l'.1011 16t Ofn' AO 1 2:,10OIq LGGb L: cMg2 u(. 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VJS1, ;tu, I'J:.d FC' U,O ! iCS(:0;1 lf: �:Ut(r,tsl,r 83UJtbI0003(. 1'CUJU C0111 rl'± tlnl2nsA' �t!.cu pl' S^ 13 's blN `u 2J04 r_=am:--_+x,x�eolnu.:_'_ -syr csv.s _.n. ,.-z r__-:. ::. xr^xvc:._zs-rv.:•_-c-.ct—�c-cv>,s.:ysce.+.a.rea„�-�.:cxws-c -.. :. � ---c v-m jpr Hull Storey Gibson Companies, LLC February 28, 2012 Mr. Samir Dumpor Environmental Engineer North Carolina Department of Environment and Natural Resources Division of Water Quality 943 Washington Square Mall Washington, North Carolina 27889 Re: Stormwater Permit No. SW7000718 Modification Twin Rivers Mall Dear Samir: /vK�.�1 iy�✓P . / 1 TO S Thank you for discussing the sequence adjustment for the captioned project. I believe I have addressed the concerns you raised below. Attached hereto as Exhibit "A" is a drawing of the proposed fill area for the Cracker Barrel at the Twin Rivers Mall. The property owner proposes to create the pad shown within the volume of the pond by moving material located below the existing top of bank elevation 22 from point to point within the pond. The earth moving activity to create the pad will take approximately 14 days and will result in a temporary increase in the volume of the pond at the existing location. The existing pond currently has a volume of approximate) 250,230 bic feet. In creating this pad, the pry ner will create, on a temporary bast , a r pond of approximately 271,900 bic feet, to handle the storm water runoff from the mall. The propertyowner into place several measures to handle and control sedimentation within this new pond: • Prior to moving dirt, the property owner will pump down the water level in the existing pond which will give a substantial reserve volume in the event of a rain event during the approximately 14 days the pad and temporary pond are being set up. • Upon the completion of the building pad and the loading of the surcharge, the pond water level will be allowed to refill to the current level, providing as much or more water quality treatment as exists with the existing pond. • The side slopes of the pond and surcharge fill will be hydro -seeded and irrigated to assure maximum grass growth to eliminate runoff from the new fill areas. • The property owner will install a double row of silt fence below the outlet of the RCP outfall for the pond to capture any sediment. ACQUISITION • DEVELOPMENT • REDEVELOPMENT 1190 Intenute Parkway Auywua, Gnipa 30909 (106) 863-2222 fax: (706) 863-1857 Simultaneous with this pad construction, the property owner will be: • Installing the new concrete outfall weir onto the adjacent state right of way; • Digging the ponds marked in Exhibit "B" attached hereto and installing the erosion and sedimentation controls in those ponds; and • Installing the new RCP within the parking lots to direct flow to the new ponds (these pipes will be plugged until the ponds are ready for the storm water). After the portion of the new ponds, (including sedimentation controls) have been completed such that the volume of the existing pond has been replaced, the plugs in the pipes will be removed, and all storm water will be redirected to the new pond system. The existing pond will be taken off line and filled with material coming out of the new pond. During this process, the property owner will perform the following measures to further protect from sediment leaving the property. After each rainfall event of 1h" or more, the property owner will: • Inspect all silt fence, and any accumulated sediments will be removed and the filter fence repaired if needed; • Inspect the sides slopes of the surcharge material for any erosion or failure; and • Sweep the parking lots of sediment. As we discussed, the existing pond is somewhat unusual in that it was installed with upland nodes. Those nodes can be moved around without diminishing the volume of the pond thereby allowing the property owner the opportunity to accelerate the surcharge process. Also, since the property owner is tripling the volume of the storm water ponds serving the property, the volume of the existing pond will be replaced early in the construction process, and the property owner can fill the existing pond directly from dirt coming out of one of the new pond areas - reducing the handling of that dirt from two times to once, reducing the volume of dirt temporarily stockpiled, and considerably shortening the project schedule - without ever reducing the volume storm water storage on the property. The changes we have been discussing make good sense to the property owner and should make good.sense to NCDENR, and I very much appreciate NCDENR's willingness to work through these final issues with me. 1 will call you to discuss and finalize. Thank you for your help. HULL ST Y GIBBON COMPANIES, LLC 4� Steve Mitchell If OWN PIPE IPF I" OPEN TOP PIPE j IPF PK NAIL lCONCRETE WEIR POND "C" 46,127 \C.F. 9 TRIO POND "D" 15,105 C.F. volume of new pond W = 271,900 c.f. 24 proposed existing contours contours Yn C, this area to be moved to surcharge pad this; sniea to be i •NA surc9a, rye, 19 21 20 f 21 zz hydroseed V . s urecharge pile 1 �j ' , I ,' \ ``x.� .� % �� ,! \� \`, .\ and all disturbed areas. �2 .1 -1\ 'k ^�\, �' \ '�. ,11 Illh�lo�n¢sonf J `�\ �.L ;\,� \. `.� \,. 17 ILL, 23 24 existing bottom of pond_ / jL�-I\ i i\ '?f fix -ting pond 22 c.f. t 0 Z' 261,�N N" 6Q'tz dime tion ring to s7-- , n / Sem;ih until,remainder, lcP 'X of po IV be filled CUR9 NL[-,T -24- .-'R/ -MARK elevation 22- CURn NLZT existing siling top of pond q cr, A I E. 7 3 maximum fill CuvO NLEI 1 .7 elevation 27, GVRB GRATE-:,,.7; A install C 74 0 sediment inspect and remove '-CURB 'PIL� T trap sediment aftei��' lee here N 1 -3. 44 1�6roatiir than eachiraid 11----*-"­CLRO MLL I (�-IPH INLET IFIAT—22 52 -T 57 �.Ti�i:T-r �S� _ slvmJ.l�c��a�� !ice ,tom tom!"J�L� • • W w.nSf��>• Wlrri arLL.a �. ram. ,qii� •� ��lvvvz� u �vvv¢�v -ems is•.r„� j uu_wvu•.� r b,� �•� wa" lvinv�, il'6ar_� !!!1l�,l�IIfJ yi .i v t1 vrvl.-lnr��-rar_ri l:�s:•am�r��s �:1l�l�:��r i FIIQS�I_i'J r:.'_Li = � vusl�reaeia�u vicelvt�s.�Ja�:i vr�lvr�rr t3i vi�}rii i��rsi�i Mom —I n 4r.��v'a!' NEW DOUBLE SHEET 2.1 ^,�'i• \ �/�,t-1 •� .sue W VEGETATIVE STRIP/POND STORAGE TORM rj. jclr. ; YJ; T 0 3 4 �' USGS MAPB OMwm IOI/I O Z TWINR MMALL /NEW BERNM DETENTION POND IMPROVEMENTS y y f ► WR TooleEnameers Ina EryFwn . ConWib PMms. 0 TWIN RIVERS MALL / NEW BERN MALL DETENTION POND IMPROVEMENTS SUPPORTING CALULATIONS 11u11/// N 9Ago/ � ,•aQ t l 111 nS 7.. 1 A232 Prepared by TE i W R Toole Engineers; Inc. Engineers---.C_o n_s Ulan-Ls�Ptanners WRTE NO.: 11 -0 16 9 0' n f� • is SUPPORTING CALCULATIONS REQUIRED POND VOLUME AND STORAGE IMPERVIOUS AREA AC FIRST 1" OF RUNOFF CUBIC FEET FIRST 1.5" OF RUNOFF CUBIC FEET IN RIVERS MALL 37.44 135,907 V EXISTING DET POND SITE 2.59 14,100 TOTAL= ( 40A 150,008 PROPOSED DETENTION POND VOLUME AND STORAGE ELEVATION ft) Surface Area (so Surface Area AC Incremental Volume c Cumulative Volume c 17.00 80,636.00 1.85 0.00 0.00 18.00 96,203.00 2.21 88,419.50 88,419.50 18.50 104,611.50 2.40 96,515.50 140,725.25 18.75 108, 815.75 2.50 100, 563.50 166, 878.13 19.00 113,020.00 2.59 104,611.50 193,031.00 19.25 117,276.75 2.69 108,842.00 223,414.38 19.50 121,533.50 2.79 113,072.50 253,797.75 20.00 130,047.00 1 2.99 121,533.50 314,564.50 STORAGE CF DETENTION POND AT 18.75 FT 166,878.13 EXISTING STORM PIPE 21,773.00 OTAL STORAGE= 188,651.13 ® POND DRAWDOWN 3.5.2. Orifice Equation The basic equation for orifices is: Q = CDAti 2gfl 1"here: Q = Discharge (cfs) CD = Coefficient of discharge (dimensionless) - see Table 3-8 A = Cross -sectional area of flocs at the orifice entrance (sq ft) = acceleration of gravity (32_' ft/sec') Ho = Driving head (ft), measured from the centroid of the orifice area to the crater surface - Note: Usually use Ho/3 to compute drawdocvn through an orifice to reflect the fact that head is decreasing as the drawdorvn occurs. L a }t Orifice size= 61nches Cd= 0.6 A= 0.1963SF 9= 32.2 ft/sec2 Ho= 0.617ft _ Q= 0.668cfs DRAWDOWN DAY CIF 1 57,730 2 115,460 3 173,190 4 230,921 5 288,651 is I1 PAVEMENT REMOVED �� ( � �'� ROPOSED DEVELOPMENT /� •.w�' _ -'V J• lam. �A A=3.12 AC (83% IMPERVIOUS) J/ 0 Y6 \ i 'PAVEMENT/ r ./ 00�0BUILDING 000` / GRASS/ O9 i I yob= N.T.S POST -DEVELOPMENT Sheet Permit (to be p iWded by DWO) 01 AT►A NCDENR STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM WET DETENTION BASIN SUPPLEMENT This form must be filled out, printed and submitted. The Required Items Checklist (Part III) must be printed, filled out and submitted along with all of the required information. O`'oF W ATF9OG o�c f.. PROJECT INFORMATION " ° , . " Project name Twin Rivers Mall I New Bern Mall Detention Pond Improvements Contact person Steve Mitchell Phone number Date Drainage area number 706-691-7097 11130011 II.. DESIGN INFORMATION ` - �_? w4 " , u<•; Site Characteristics Drainage area 2,266,862 ft' 52- %4 Impervious area, post -development 1,743,707 ft' 40.03 % impervious 76.92 % Design rainfall depth 1.0 in Storage Volume: Non -SA Waters Minimum volume required 150,008 ft' OK Volume provided 188,651 ft3 OK, volume provided is equal to or in excess of volume required. Storage Volume: SA Waters 1.5' runoff volume ft3 Pre -development 1-yr, 24-hr runoff ft3 Post -development 1-yr, 24-hr runoff ft3 Minimum volume required It, Volume provided ft3 Peak Flow Calculations Is the pre/post control of the lyr 24hr storm peak Bow required? N (Y or N) 1-yr, 24-hr rainfall depth NA in Rational C, pre -development NA (unitless) Rational C, post -development NA (unitless) Rainfall intensity: 1-yr, 24-hr storm NA in1hr #VALUE! Pre -development 1-yr, 24-hr peak Bow NA ft3lsec Post -development 1-yr, 24-hr peak Bow NA ft3lsec Pre/Post 1-yr, 24-hr peak Bow control #VALUE! ft3lsec Elevations Temporary pool elevation Permanent pool elevation SHWT elevation (approx. at the pen. pool elevation) Top of 1Oft vegetated shelf elevation Bottom of 1 Oft vegetated shelf elevation Sediment cleanout, top elevation (bottom of pond) Sediment cleanout, bottom elevation Sediment storage provided Is there additional volume stored above the state -required temp. pool? Elevation of the lop of the additional volume 18.75 fmsl 17.00 hnsl 17.00 first NA foul NA fmsl 13.00 fmsl 8.00 fmsl 5.00 ft NA (Y or N) 18.8 fnsl OK Form SW401-Wet Detention Basin-Rev.8-9117/09 Parts 1.811. Design summary, Page i of 2 Permit No. fie be provided by DWO) IL DESIGN INFORMATION „`. Surface Areas Area, temporary pool 108,816 ft' Area REQUIRED, permanent pool SAIDA ratio #VALUE! ftt NA (unifiess) Area PROVIDED, permanent pool, Apr,,,, c, 67,639 It #VALUEI Area, bottom of IN vegetated shelf, Ate, NA ftt Area, sediment cleanoul, lop elevation (bottom of pond), Ate. 30,518 ft? Volumes Volume, temporary pool 188,651 ft3 OK Volume, permanent pool, Vpe, " NA ft' Volume, forebay (sum of forebays if more than one forebay) NA ft' Forebay %of permanent pool volume #VALUEI % #VALUEI SAIDA Table Data Design TSS removal NA % Enter either 85 or 90 Coastal SAIDA Table Used? NA (Y or N) Mountain/Piedmont SA/DA Table Used? NA (Y or N) SAIDA ratio NA limitless) Average depth (used in SAIDA table): Calculation option 1 used? (See Figure 10-2b) NA (Y or N) Volume, permanent pool, Vs,,,, cel NA ft7 Area provided, permanent pool, Ate,,, cod 67,639 ft Average depth calculated NA If OK Average depth used in SAIDA, dN, (Round to nearest 0.511) NA If #VALUEI Calculation option 2 used? (See Figure 10-2b) NA (Y or N) Area provided, permanent pool, A._. 67,639 ftz Area, bottom of 10ft vegetated shelf, A, pie, NA ft7 Area, sediment deanout, top elevation (bottom of pond), Ad ova 30,518 ft' 'Depth' (distance blw bottom of 1 Oft shelf and lop of sediment) #VALUE! ft Average depth calculated NA If OK ® Average depth used in SAIDA, d., (Round to nearest 0.5ft) NA If #VALUEI Drawdowm Calculations Drawdown through orifice? Y (Y or N) Diameter of orifice (if circular) 6.00 in Area of orifice (if -non -circular) int Coefficient of discharge (Co) 0.60 (unitless) Driving head (Ho) 0.62 it Drawdown through weir? N (Y or N) Weir type NA (unidess) Coefficient of discharge (C.) NA limitless) Length of weir (L) NA ft Driving head (H) NA ft Pre development 1-yr. 24-hr peak Bow NA ft`/sec Past -development 1-yr, 24-hr peak flow NA ft7/sec Storage volume discharge rate (through discharge orifice or weir) 0.74 fts/sec Storage volume dmwdown time 2.64 days OK, draws down in 2-5 days. Additional Information Vegetated side slopes 2' :1 OK Vegetated shelf slope NA :1 OK Vegetated shelf width NA It OK Length of flowpath to width ratio NA :1 OK Length to width ratio NA :1 OK Trash rack for overflow 8 onfce? Y (Y or N) OK Freeboard provided NA It OK Vegetated filter provided? NA (Y or N) OK Recorded drainage easement provided? NA (Y or N) OK Capures all mnoff at ultimate build -out? NA (Y or N) OK Drain mechanism for maintenance or emergencies is: Pond to be pumped in emergencies Form SW401-Wet Detention Basin-Rev.8-9117/09 Paris 1.811, Design Summary. Page 2 of 2 sr NC®ENR North Carolina Department of Environment and Natural Resources Beverly Eaves Perdue Governor Mr. John W. Gibson HIS New Bern, LLC C/o Hull Storey Gibson Companies, LLC 1190 Interstate Pkwy Augusta, GA 30909 Dear Mr. Gibson: Division of Water Quality Coleen H. Sullins Director October 19, 2009 Subject: NOTICE OF INSPECTION Permit No. SW7000718 Twin Rivers Mall Craven County Dee Freeman Secretary On September 30, 2009, Mr. Samir Dumpor of the Washington Regional Office of the Division of Water Quality (DWQ) inspected the Twin Rivers Mall development in New Bern, Craven County to determine compliance with Stormwater Management Permit Number SW7000718, which was issued on September 25, 2000, and renewed on October 19, 2009. DWQ file review and site inspection revealed that the project is in substantial compliance with the approved permit, however the site needs additional maintenance. Please notify this Office if a sediment accumulation survey has been completed on the stormwater wetland system and submit the results. If one has not been completed, please due so as soon as possible and forward the results to this Office. If sediment has accumulated to the removal benchmark (25% of the original depth) as set out in your Operation & Maintenance Agreement, this sediment needs to be removed and disposed of properly. Please submit a Plan of Action, which will outline a timetable for the completion of this work. Please have the banks of the wetland maintain properly. There is an excessive amount of weeds and small woody vegetation located around the wetland. Remove the small trees that grow on banks of the wetland. Please submit the required information as requested above by November 19, 2009 or have a written Plan of Action submitted by this date. If additional time is needed to complete these items, please submit a written request giving reasons by this date. Please be advised that you are required to comply with the terms, conditions and limitations of your Stormwater Management Permit under. Title 15A North Carolina Administrative Code 2H .1003 and North Carolina General Statute 143-214.7, including operation and maintenance of your permitted stormwater system. Please be advised that violations of your Stormwater Management Permit may be subject to the assessment of civil penalties of up to $25,000 per day per violation. If you have any questions please contact me at the Washington Regional Office, telephone number (252) 946-6481. North Carolina Division of Water Quality Internet: www.ncwatereualitv.oro 943 Washington Square Mall Phone: 252-946-6481 Washington, NC 27889 FAX 252-946-9215 An Equal OpportunitylAffrmative Action Employer- 50% Recycled/f 0% Post Consumer Paper NorthCarolina Naturally Sincerely, Samir Dumpor Environmental Engineer cc: WaRO Files ® Hull Storey Gibson Companies, LLC December 10, 2009 Mr. Samir Dumper NC Division of Water Quality 943 Washington Square Mall Washington, NC 27889 RE: Twin Rivers/New Bern Mall Permit 4 SW 7000718 Action Plan for Compliance with Notice of Inspection Dear Mr. Dumpor. Below is our schedule for assessment and maintenance of the Twin Rivers/New Bern Mall stormwater detention facility. This schedule takes into account the scheduling of consultants and contractors and potential weather delays. Monday, December 7, 2009 — Obtained the NCDENR records related to design of the stormwater detention system Thursday, December 10- Monday, December 14, 2009 — Review of records and design by civil engineer and Hull Storey Gibson staff Tuesday, December 14, 2009- Friday, December 18, 2009 — Perform Siltation Survey and pond assessment on site December 28 — December 31, 2009 — Maintenance Analysis and pricing (based on silt accumulation and engineer's assessment of outlet structure) January 18 — February 5, 2010 — Removal of trees, woody vegetation and weeds from the stormwater detention area February 8-March 2, 2010 — Removal and disposal of silt (if required based on siltation survey, NCDENR regulations and civil engineer's assessment) If you have any questions or need additional information, please email me at k iones(il)hu l lstorevt;ibson.com. ACQUISITION . DEVELOPMENT . REDEVELOPMENT 119D Interstate Parkway Augusta, Georgia 30909 (106) B63-2222 fax: (706) 868-7457 Sincerely, H/S NEW BERN, LLC HULL STOREY GIBSON COMPANIES, LLC \"o - Kendal R. Jones VP/Development ACQUISITION . DEVELOPMENT . REDEVELOPMENT 1190 Interstate Parkway Augusta, Georgia 30909 (706) 863-2222 Fax: (706) 868-7457 HAINES, GIPSON & ASSOCIATES, INC. CONSULTING ENGINEERS THOMAS G. HAINES, P.E. SCOTT E. SAMUEL, P.E. RANDALL W. GIPSON, P.E GLENN A. GRAHAM, P.E. R. CI -AY LEWIS, P.E. JOSEPH A. NICHOLSON, P.E. DANIE.L D. CAMPBELL, P.E. DAVID A. DOMYSLAWSKI, P.E. JEFFREY 0. STRICKLAND, P.E. STONCY C. ABERCROMBIE, P.E. KRISTOPHER M. CAMPBELL, P.E. MATTHEW T. COGGINS, P.E. STEPHEN, J. SYWY, P.E. DAVID H. LOVVORN, P.E ROBE.RT A. McCANN, P.E. December 22. 2009 Kendal Jones Mull, Storey New Bern, LLC 1190 Interstate Parkway Augusta, Georgia 30909 RE: Stormwater Wetland Sediment Accumulation Survey New Bern Mall NCDENR Permit No. SW7000718 FIGA Job No. 2009-213.01 Kendal: On today's date, I have inspected the New Bern Mall stormwater facility to determine it sediment has accumulated to the removal benchmark (25% of the original depth) and needs to be removed. The inspection included the inlet, outlet, banks and the ponded area using a small boat. As noted in Chapter 9 — Stormwater Wetlands of the NCDENR Stomiwater BMP Manual, sediments should only be selectively removed from stormwater wetlands, primarily from the forebay. Additionally, accumulated sediment should be removed from around inlet and outlet structures. In the New Bern Mall facility, no forebay or deep pools in the ponded area or at the outlet are apparent. The ponded area has a shallow, uniform bottom covered with decaying vegetative matter. No sediments are visible. This may be due to the vegetative cover on the banks and inlet swale and the lack of land disturbing activities in the drainage basin. Sediments in the form of vegetation and trash/debris transported by run-off do appear at the grass-swale inlet and the outlet filter ring that was placed in 2000. To maintain free Flow in and out the pond, these materials should be removed. Please do not hesitate to contact me if I can provide any additional information. Very truly yours, HAINES, GIPSON & ASSOCIATES, INC. Jeffrey B. Strickland, P.E. enclosure 1550 NORTH BROWN ROAD SUITE 100 LAWRENCEVILLE, GEORGIA 30043 (770)491-7550 FAX t770) 491,7750 CIVIL . RUCTURAL BRIDGE ;l, �ijyyyyy������ 4v H''f- °t�'�.9�y.�}i'/A �'� a JId3N Y <L y�✓ ,�i}}H,,..�M .. a. 4 t I,�� 44 ,iijF'I� 'y "' t N%! 2 � HAINES, GIPSON & ASSOCIATES, INC CONSULTING ENGINEERS THOMAS G. HAINES, P.E. SCOTT E. SAMUEL, P.E. . RANDALL W. GIPSON, P.E GLENN A. GRAHAM, P.E. R. CLAY LEWIS, P.E. JOSEPH A. NICHOLSON, P.E. DANIEL D. CAMPBELL, P.E. DAVID A. DOMYSLAWSKI, P.E. JEFFREY B. STRICKLAND, P.E. STONEY C. ABERCROMBIE, P.G. KRISTOPHER M. CAMPBE.LL, P.E. MATTHEW T. COGGINS, P.E. STEPHEN, J. SYWY, P.E. DAVID H. LOVVORN, P.E ROBERTA, McCANN, P.E. December 22, 2009 Kendal Jones Bull, Storey New Bern, LLC 1 190 Interstate Parkway Augusta, Georgia 30909 RE: Stormwater Wetland System Review FIGA Job No. 2009-213.01 Kendal: A visual inspection of the New Bern Mall stormwater facility took place to determine how it functions and what maintenance operations need to take place for proper operation. The system, classified in your Stormwater Permit No. SW7000718 as a "stormwater wetland", maintains a shallow but permanent pool with no apparent outlet device other than the barrel of a 36" culvert. Vegetation on the banks will need to be removed but no sediments other than decayed vegetation and trash/debris from the adjacent retail uses appear in the pond. To function as a "stormwater wetland", the facility must meet all of the major design elements listed at the beginning of Chapter 9 — Stormwater Wetlands, found in the NCDENR Stormwater BMP Manual, The New Bern Mall stormwater facility does not appear to include the following: I. side slopes no greater than 3:1 2. facility located in a recorded drainage easement 3. wetland draw -down in 2 to 5 days 4. inlet forebay 5. max. shallow land depth (temp. pool) of P-0" 6. deep pools 7. shallow water (3" to 6") 8. outlet/draw down device With these required elements not being present, the facility may have been incorrectly classified as a stormwater wetland. Reconfiguration as a wet detention pond, a facility that does not require the vast surface area of a stormwater wetland may be possible. Permitting through NCDENR and other state/federal agencies might be required depending on the presence of any wetland and/or state waters. Very truly yours, HAINES, GIPSON& ASSOCIATES, INC. -:�� 4_4W-,1 Jeffrey B. Strickland, P.E. 1550 NORTH BROWN ROAD SUITE 100 LAWRENCEVILLE, GEORGIA 30043 (770) 491-7550 FAX (770) 491-7750 CIVIL STRUCTURAL BRIDGE MALL Stormwater Wetlands Inspection Report (monthly & within 24 hours after every storm event greater than 1.5 inches) Inspector Name & Title: Jeff Strickland, P.E. Inspection Date: 22 November 2009 Code Key: n/a = Not Applicable M = Monitor (potential for future problem) NP = Not a Problem WN = Work Needed Inflow Points `Assessment Code -'.` , .: ' ' - ` ' Ex lanation ' " ..: ' , Obstruction Vegetation/debris/sediment WIN Inflow to system clogged with debris and trash. Vegetation slowing run-off needs to be removed. Erosion/undercutting NP Displacement of fabric/ Rip -rap NP Pipe Condition nla Other (describe) Foreba 'Assessment' " '•` :.. Code _ Explanation' Accumulation Vegetation/debris/sediment Side Slope Erosion Invasive Vegetation Other (describe) n/a No forebay present. Deep Pool, Shallow Water, Shallow Land Areas Assessment Code Explanation Shallow land flooded >5 days after storm n/a Shallow land not evident. Dry areas appear too high to be flooded. Accumulation Vegetation/debris/sediment WN Vegetation needs to be removed from banks of system. Plants are Dead/disease/dying n/a Vegetation length too short/long) n/a Bare soil/erosion gullies n/a Invasive vegetation (%) n/a Algae cover (%) n/a Other (describe) Embankment/Micropool 'Assessment Code Explanation - Erosion and/or loss of dam n/a No micropool is evident. Material Shrub/trees present n/a _ embankment Animal burrows n/a embankment Accumulation Vegetation/ n/a debris/sediment/ micro ool Invasive vegetation n/a (micropool) Other (describe) Outlet Device Assessment. Code, ,.'Explanation.' d Obstruction Vegetation/debris/sediment WN Outflow is through open pipe with no outlet device. Erosion/undercutting NP Joint failure/loss of joint Material NP Leaking device n/a Other (describe) WN Vegetation needs to be removed from existing filter ring at outlet pipe. Miscellaneous ."Assessment: _; ;, Code.' Explanation Trash/Debris WN Accumulated trash needs to be removed from system. Access WN Removal of vegetation from banks will improve/provide access to system. Vandalism n/a Fence Condition NP Fish/wildlife observations NP Signage n/a Other (describe) Photographs Attach digital photographs of the site and structural BMP'S including a caption describing the photo. Inspector Initials jbs JJ/ . . P". yw+ a t5 , f�In rt �'i �'h ,.�"�3'�,,y^�'�p•� 4i' S i « 'f� M 1 4S ' f5 rW ,+,, , \ i � �"':1�� �.� J .,S �� to ;'•.r.RAe�.N4f �j5 1M� .Y i't r'4}Y�'��:`L f�b, �,y� r ,. �.-..!'✓ f:»d,� .' � 4 fit!¢ it n.:�'S�" I �w .J 71yy }�`''�O�Ti"✓y1y��i..7 Dumpor, Samir From: Kendal Jones [kjones@hullstoreygibson.com] Sent: Monday, March 01, 2010 3:22 PM To: Dumper, Samir Cc: jeff strickland, P.E. Subject: RE: Twin Rivers/New Bern Mall SW 7000718 Attachments: sediment survey letter.pdf; stormwater system classification letter.pdf; new bern malll stormwater wetland inspection report.pdf Follow Up Flag: Follow up Flag Status: Flagged Attached are the engineer's inspection reports for our file. I will let you know as soon as we remove the vegetation from the banks. Thanks for your help! Kendal R. Jones Hull Storey Gibson Companies, LLC 7o6.855.064 From: Dumpor, Samir [mailto:samir.dumpor@ncdenr.gov] Sent: Friday, December 11, 2009 10:06 AM To: Kendal Jones Subject: RE: Twin Rivers/New Bern Mall SW 7000718 Kendal, Proposed plan of action looks good to me. Please send me an e-mail when the work gets done, so I can close this project. Thanks Samir From: Kendal Jones [mailto:kjones@hullstoreygibson.com] Sent: Thursday, December 10, 2009 5:09 PM To: Dumper, Samir Subject: Twin Rivers/New Bern Mall SW 7000718 Samir: Please review the attached action plan and email me if you have any questions K. Kendal R. Jones Hull Storey Gibson Companies, LLC 1190 Interstate Parkway Augusta, Georgia 30909 7o6.855.4o64 NEW BERM rtas � � zoto MALL �' h Stormwater Wetlands Inspection Report Inspector Name & Title: Jeff Strickland, P.E. Inspection Date: 22 November 2009 Code Key: n/a = Not Applicable M = Monitor (potential for future problem) NP. = Not a Problem WN = Work Needed Inflnu, Dninlc Assessment Code Explanation Obstruction Vegetation/debris/sediment WN Inflow to system clogged with debris and trash. Vegetation slowing run-off needs to be removed. Erosion/undercutting NP Displacement of fabric/ Rip -rap NP Pipe.Condition n/a Other (describe) n/a Cnrnhn., Assessment Code Explanation Accumulation Vegetation/debris/sediment n/a No forebay present. Side Slope Erosion n/a Ihvasive Vegetation n/a Other (describe) • n/a i nPen Pnnl_ Shallow Water. Shallow Land Areas Assessment Code Explanation Shallow land flooded >5 days after storm n/a Shallow land not evident. Dryareas appear too high to be flooded. Accumulation Vegetation/debris/sediment WN Vegetation needs to be removed from banks of system. Plants are Dead/disease/dying n/a Vegetation length too short/long) n/a Bare soil/erosion gullies n/a Invasive vegetation (%) n/a Algae cover (%) n/a Other (describe) n/a Embankment/Micro ool Assessment Code Explanation Erosion and/or loss of dam n/a No micropool is evident. Material Shrub/trees present n/a embankment Animal burrows n/a embankment Accumulation Vegetation/ n/a debris/sediment/ micro ool Invasive vegetation nla micro ool Other (describe) n/a Outlet Device Assessment Code Explanation Obstruction Vegetation/debris/sediment WN Outflow is through open pipe with no outlet device. Erosion/undercutting NP Joint failure/loss of joint Material NP Leaking device n/a Other (describe) WN Vegetation needs to be removed from existing filter ring at outlet pipe. RR'a. nlh�e�uc IIIJYYIYI IV VYv Assessment Code Explanation Trash/Debris WN Accumulated trash needs to be removed from system. Access WN Removal of vegetation from banks will improve/provide access to system. Vandalism n/a Fence Condition NP Fish/wildlife observations NP Signage nla Other (describe) n/a Photographs Attach digital photographs of the site and structural BMP'S including a caption describing the photo. Grlditinnal Comments, To function as a "stormwater wetland", the facility must meet all of the major design elements listed at the beginning of Chapter 9 — Stormwater Wetlands, found in the NCDENR Stormwater BMP Manual. The New Bem Mall stormwater facility does not appear to include the following. I side slopes no greater than 3:1 2. facility located in a recorded drainage easement 3. wetland draw -down in 2 to 5 days 4. inlet forebay 5. max. shallow land depth (temp. pool) of F-0" 6. deep pools 7. shallow water (3" to 6") 8. outlet/draw down device With these required elements not being present, the facility may have been incorrectly classified as a stormwater wetland. Inspector Initials ibs . �. tl.I• a Ifta rN%l, MAIL, il 3 Ponded Surface J /Ae st ; r f •y i • q.-.i EiN4p a t♦ X'� d �..it G CONSULTING ENGINEERS THOMAS G. HAINES, P.E. RANDALL W. GIPSON, P.E R. CLAY LEWIS, P.E. DANIEL D. CAMPBELL, P.E. JEFFREY B. STRICKLAND, P.E. KRISTOPHER M. CAMPBELL, P.E. STEPHEN, J. SYWY, P.E. ROBERT A. McCANN, P.E. December 22, 2009 Kendal Jones Hull, Storey New Bern, LLC 1190 Interstate Parkway Augusta, Georgia 30909 RE: Stormwater Wetland Sediment Accumulation Survey New Bern Mall NCDENR Permit No. SW7000718 HGA Job No. 2009-213.01 Kendal: SCOTT E. SAMUEL, P.E. GLENN A. GRAHAM, P.E. JOSEPH A. NICHOLSON, P.E. DAVID A. OOMYSLAWSKI, P.E. STONEY C. ABERCROMBIE. P.E. MATTHEW T. COGGINS. P.E. DAVID H. LOVVORN, P.E On today's date, I have inspected the New Bem Mall stormwater facility to determine if sediment has accumulated to the removal benchmark (25% of the original depth) and needs to be removed. The inspection included the inlet, outlet, banks and the ponded area using a small boat. As noted in Chapter 9 — Stormwater Wetlands of the NCDENR Stormwater BMP Manual, sediments should only be selectively removed from stormwater wetlands, primarily from the forebay. Additionally, accumulated sediment should be removed from around inlet and outlet structures. In the New Bern Mall facility, no forebay or deep pools in the ponded area or at the outlet are apparent. The ponded area has a shallow, uniform bottom covered with decaying vegetative matter. No sediments are visible. This may be due to the vegetative cover on the banks and inlet Swale, the facility's immediate location where no recent land disturbing activities have taken place and the acceptable level of sediment & erosion control practices of any recent, off -site land disturbing activities by others in the overall drainage basin. Sediments in the form of vegetation and trash/debris transported by run-off do appear at the grass-swale inlet and the outlet filter ring that was placed in 2000. To maintain free flow in and out the pond, these materials should be removed. Please do not hesitate to contact me if I can provide any additional information. Very truly yours, HAINES, GIPSON & ASSOCIATES, INC Jeffrey B. Strickland, P.E. enclosure 1550 NORTH BROWN ROAD SUITE 100 LAWRENCEVILLE, GEORGIA 30043 (770) 491-7550 FAX (770) 491-7750 OVIL SrRUCTURAL BRIDGE I It OR k, All I HAINES, GIPSON & ASSICIA , CONSULTING ENGINEERS THOMAS G. HAINES, P.E. RANDALL W. GIPSON, P.E R. CLAY LEWIS, P.E. DANIEL D. CAMPBELL, P.E. JEFFREY S- STRICKLAND. P.E. KRISTOPHER M. CAMPBELL, P.E. STEPHEN, J. SYWY, P-E. ROBERT A. McCANN, P.E. December 22, 2009 Kendal Jones Hull, Storey New Bern, LL.0 1 190 Interstate Parkway Augusta, Georgia 30909 RE: Stormwater Wetland System Review HGA Job No. 2009-213.01 Kendal: SCOTT E. SAMUEL, P.E. GLENN A. GRAHAM, P.E. JOSEPH A. NICHOLSON, P.E. DAVID A. DOMYSLAWSKI, P.E. STONEY C. ABERCROMBIE, P.E. MATTHEW T. COGGINS, P.E. DAVID H. LOVVORN, P.E A visual inspection of the New Bern Mall stormwater facility took place to determine how it functions and what maintenance operations need to take place for proper operation. The system, classified in your Stormwater Permit No. SW 7000718 as a "stormwater wetland", maintains a shallow but permanent pool with no apparent outlet device other than the barrel of a 36" culvert. Vegetation on the banks will need to be removed but no sediments other than decayed vegetation and trash/debris from the adjacent retail uses appear in the pond. To function as a "stormwater wetland", the facility must meet all of the major design elements listed at the beginning of Chapter 9 — Stormwater Wetlands, found in the NCDENR Stormwater BMP Manual. The New Bern Mall stormwater facility does not appear to include the following: I . side slopes no greater than 3: l 2. facility located in a recorded drainage easement 3. wetland draw -down in 2 to 5 days 4. inlet forebay 5. max. shallow land depth (temp. pool) of V-0" 6. deep pools 7. shallow water (3" to 6") 8. outlet/draw down device With these required elements not being present, it could be argued that the facility has been incorrectly classified as a stormwater wetland. Very truly yours, HAINES, GIPSON & ASSOCIATES, INC, Jeffrey B. Strickland, P.E. 1550 NORTH BROWN ROAD SURE 100 LAWRENCEVILLE, GEORGIA 3OD43 (770)491-7550 FAX (770) 491-77SO CIVR STRUCTURAL BRIDGE