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HomeMy WebLinkAboutSW8060834_CURRENT PERMIT_20061005STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS �o?)34 PERMIT NO. SW DOC TYPE � CURRENT PERMIT ❑ APPROVED PLANS ❑ HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE YYYYMMDD OF w A r�R QG 0 Y October 5, 2006 Mr Gerard J Skehan, Manager Darske, LLC 42 Yaupon Way Oak Island, NC 28465 Subject* Stormwater Permit No SW8 060834 4570 Long Beach Road High Density Project Brunswick County Dear Mr Skehan Michael F Easley, Govemor William G Ross Jr Secretary North Carolina Department of Environment and Natural Resources Alan W Klimek, P E Director Division of Water Quality The Wilmington Regional Office received a complete Stormwater Management Permit Application or 4570 Long Beach Road on September 6, 2006 Staff review of the plans and specifications has determined that the project, as proposed, will comply with the Stormwater Regulations set forth in Title 15A NCAC 2H 1000 We are forwarding Permit No SW8 060834 dated October 5, 2006, for the construction of the subject project This permit shall be effective from the date of issuance until October 5, 2016, and shall be subject to the conditions and limitations as specified therein Please pay special attention to the Operation and Maintenance requirements in this permit Failure to establish an adequate system for operation and maintenance of the stormwater management system will result in future compliance problems If any parts, requirements, or limitations contained in this permit are unacceptable, you have the right to request an adjudicatory hearing upon written request within sixty (60) days following receipt of this permit This request must be in the form of a written petition, conforming to Chapter 150B of the North Carolina General Statutes, and filed with the Office of Administrative Hearings, P O Drawer 27447, Raleigh, NC 27611-7447 Unless such demands are made this permit shall be final and binding ' If you have any questions, or need additional information concerning this matter, please contact Paul Bartlett, or me at (910) 796-7215 Sing y, Edwar ck Regional Supervisor Surface Water Protection Section ENB/ptb S 1WQSISTORMWATERIPERMIT1060834 oct06 cc Brad Sedgwick, P E , JBS Consulting, PA Delaney Aycock, Brunswick County Building Inspections Jeff Phillips, Brunswick County Engineering ,Paul T Bartlett,_P_ E 7almin'gto RggionalOffice Central -Files One Nor hCarohna Natumily North Carolina Division of Water Quality 127 Caidinal Drive Extension Wilmington, NC 28405 Phone (910) 796 7215 Customer Service Wilmington Regional Office Internet www ncwattiquahty org Fax (910) 350-2004 1 877 623 6748 An Equal OpportumtylAffirmative Action Employer — 50% Recycledl10% Post Consumer Paper State Stormwater Management Systems Permit No SW8 060834 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT HIGH DENSITY DEVELOPMENT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO Gerard J Skehan and Darske, LLC 4570 Long Beach Road Brunswick County FOR THE construction, operation and maintenance of an underground infiltration trench system in compliance with the provisions of 15A NCAC 2H 1000 (hereafter referred to as the "stormwater rules') and the approved stormwater management plans and specifications and other supporting data as attached and on file with and approved by the Division of Water Quality and considered a part of this permit This permit shall be effective from the date of issuance until October 5, 2016, and shall be subject to the following specified conditions and limitations I. DESIGN STANDARDS 1 This permit is effective only with respect to the nature and volume of stormwater described in the application and other supporting data 2 This stormwater system has been approved for the management of stormwater runoff as described in Section 16 on page 3 of this permit The stormwater control has been designed to handle the runoff from 32,620 square feet of impervious area (Trench A & B 8,491 sq ft each, Trench C 15,638 sq ft) The three trench systems must be operated with a 30' vegetated filter 3 The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per approved plans 4 All stormwater collection and treatment systems must be located in eithery dedicated common areas or recorded easements The final plats for the project will be recorded showing all such required easements, in accordance with the approved plans 5 The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system Page 2 of 7 N State Stormwater Management Systems Permit No SW8 060834 6 The following design criteria have been provided in the infiltration trenches and must be maintained at design conditions Infiltration Trench Trench A Trench B Trench C a Drainage Area, acres 021 021 038 Onsite, ft 9,243 9,243 16,634 Offsite, ft None None None b Total Im ervious Surfaces, ft 8,491 8,491 15,638 c Design Storm, Inches 1 0 1 0 1 0 d Trench Dimensions*, L x W x H, ft 432 x 3 x 1 432 x 3 x 1 816 x 3 x 1 e Perforated Pipe Diameter/Len th* 10" 01432' L 10"0/432' L 10" 01816' L f Bottom Elevation, FMSL 24 0 (97 0 per benchmark) 24 0 (97 0 per benchmark) 24 5 (97 5 per benchmark) Bypass Weir Elevation, FMSL 25 0 (98 0 per benchmark) 25 0 (98 0 per benchmark) 25 5 (98 5 per benchmark) h Permitted Storage Volume, ft 680 680 1,246 I T e of Soil Yaupon Silty Clay Yaupon Silty Clay Yaupon Silty Clay Expected Infiltration Rate, inlhr 33 33 33 k Seasonal High Water Table, FMSL 1 22 0 (95 0 per benchmark) 22 0 95 0 per benchmark) 22 5 (95 5 per benchmark I Time to Draw Down, hours 1 9 1 1 9 1 9 m Receiving Stream/River Basin calf Gulley Creek/Cape Fear n Stream Index Number 18-88-9-3-3-1 o Classification of Water Body SC, Sw, HQW *Based on a single run of pipe II SCHEDULE OF COMPLIANCE The stormwater management system shall be constructed in its entirety, vegetated and operational for its intended use prior to the construction of any built -upon surface 2 During construction, erosion shall be kept to a minimum and any eroded areas of the system will be repaired immediately 3 The permittee shall at all times provide the operation and maintenance necessary to assure the permitted stormwater system functions at optimum efficiency The approved Operation and Maintenance Plan must be followed in its entirety and maintenance must occur at the scheduled intervals including, but not limited to a Semiannual scheduled inspections (every 6 months) b Sediment removal c Mowing and revegetation of slopes and the vegetated filter d Immediate repair of eroded areas e Maintenance of all slopes in accordance with approved plans and specifications f Debris removal and unclogging of bypass structure, filter media, flow spreader, catch basins, piping and vegetated filter g A clear access path to the bypass structure must be available at all times 4 Records of maintenance activities must be kept and made available upon request to authorized personnel of DWQ The records will indicate the date, activity, name of person performing the work and what actions were taken 5 The facilities shall be constructed as shown on the approved plans This permit shall become voidable unless the facilities are constructed in accordance with the conditions of this permit, the approved plans and specifications, and other supporting data Page 3 of 7 State Stormwater Management Systems Permit No SW8 060834 R 6 Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to operation of this permitted facility, a certification must be received from an appropriate designer for the system installed certifying that the permitted facility has been installed in accordance with this permit, the approved plans and specifications, and other supporting documentation Any deviations from the approved plans and specifications must be noted on the Certification A modification may be required for those deviations 7 If the stormwater system was used as an Erosion Control device, it must be restored to design condition prior to operation as a stormwater treatment device, and prior to occupancy of the facility 8 Access to the stormwater facilities shall be maintained via appropriate easements at all times 9 The permittee shall submit to the Director and shall have received approval for revised plans, specifications, and calculations prior to construction, for any modification to the approved plans, including, but not limited to, those listed below a Any revision to any item shown on the approved plans, including the stormwater management measures, built -upon area, details, etc b Project name change c Transfer of ownership d Redesign or addition to the approved amount of built -upon area or to the drainage area e Further subdivision, acquisition, lease or sale of all or part of the project area The project area is defined as all property owned by the permittee, for which Sedimentation and Erosion Control Plan approval or a CAMA Major permit was sought f Filling in, altering, or piping of any vegetative conveyance shown on the approved plan 10 The permittee shall submit final site layout and grading plans for any permitted future areas shown on the approved plans, prior to construction 11 A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum of ten years from the date of the completion of construction 12 The Director may notify the permittee when the permitted site does not meet one or more of the minimum requirements of the permit Within the time frame specified in the notice, the permittee shall submit a written time schedule to the Director for modifying the site to meet minimum requirements The permittee shall provide copies of revised plans and certification in writing to the Director that the changes have been made III GENERAL CONDITIONS This permit is not transferable except after notice to and approval by the Director In the event of a change of ownership, or a name change, the permittee must submit a formal permit transfer request to the Division of Water Quality, accompanied by a completed name/ownership change form, documentation from the parties involved, and other supporting materials as may be appropriate The approval of this request will be considered on its merits and may or may not be approved The permittee is responsible for compliance with all permit conditions until such time as the Division approves the transfer request Page 4 of 7 Y State Stormwater Management Systems Permit No SW8 060834 2 Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to enforcement action by the Division of Water Quality, in accordance with North Carolina General Statute 143-215 6A to 143-215 6C 3 The issuance of this permit does not preclude the Permittee from complying with any and all statutes, rules, regulations, or ordinances, which may be imposed by other government agencies (local, state, and federal) having jurisdiction 4 In the event that the facilities fail to perform satisfactorily, including the creation of nuisance conditions, the Permittee shall take immediate corrective action, including those as may be required by this Division, such as the construction of additional or replacement stormwater management systems 5 The permittee grants DENR Staff permission to enter the property during normal business hours for the purpose of inspecting all components of the permitted stormwater management facility 6 The permit may be modified, revoked and reissued or terminated for cause The filing of a request for a permit modification, revocation and reissuance or termination does not stay any permit condition 7 Unless specified elsewhere, permanent seeding requirements for the stormwater control must follow the guidelines established in the North Carolina Erosion and Sediment Control Planning and Design Manual 8 Approved plans and specifications for this project are incorporated by reference and are enforceable parts of the permit 9 The permittee shall notify the Division any name, ownership or mailing address changes within 30 days Permit issued this the 5th day of October 2006 NOR CAROLI ENVIRONMENTAL MANAGEMENT COMMISSION for A an W Klimek, P E , Director Division of Water Quality By Authority of the Environmental Management Commission Page 5 of 7 State Stormwater Management Systems Permit No SW8 060834 4570 Long Beach Road Stormwater Permit No SW8 060834 Brunswick County Designer's Certification Page 1 of 2 I, , as a duly registered in the State of North Carolina, having been authorized to observe (periodically/ weekly/ full time) the construction of the project, (Project) for (Project Owner) hereby state that, to the best of my abilities, due care and diligence was used in the observation of the project construction such that the construction was observed to be built within substantial compliance and intent of the approved plans and specifications The checklist of items on page 2 of this form is included in the Certification Noted deviations from approved plans and specification Signature Registration Number Date SEAL Page 6 of 7 f State Stormwater Management Systems Permit No SW8 060834 Page 2of2 Certification Requirements 1 The drainage area to the system contains approximately the permitted acreage 2 The drainage area to the system contains no more than the permitted amount of built -upon area 3 All the built -upon area associated with the protect is graded such that the runoff drains to the system 4 All roof drains are located such that the runoff is directed into the system 5 The bypass structure elevations are per the approved plan 6 The bypass structure is located per the approved plans 7 A Trash Rack is provided on the outlet/bypass structure 8 All slopes are grassed with permanent vegetation 9 Vegetated slopes are no steeper than 3 1 10 The inlets are located per the approved plans and do not cause short- circuiting of the system 11 The permitted amounts of surface area and/or volume have been provided 12 All required design depths are provided 13 All required parts of the system are provided 14 The required system dimensions are provided per the approved plans cc NCDENR-DWQ Regional Office Delaney Aycock, Brunswick County Building Inspections Jeff Phillips, Brunswick County Engineering Page 7 of 7 r_ , k g/a-zItNlo $ 2 DUv, D o 1 Z 7 7 ylt-/o 6 AeoPIpv � Z State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM This form may be photocoptedfor use as an original L GENERAL INFORMATION: Applicant's name (specify the name of the corporation, individual, etc who owns the project) Darske, LLC 2 Print Owners/Signing Official's name and title (the person legally responsible for facility and compliance) Gerard J Skehan, Manager 3 Mailing Address for person listed in item 2 above 42 Yaupon Way City Oak Island State NC Zip 28465 Telephone Number (910) 278-9084 _ 4 Project Name (subdivision, facility, or establishment name -should be consistent with project name on plans, specifications, letters, operation and maintenance agreements, etc ) 4570 Long Beach Road 5 Location of Project (street address) 4570 Long_Beach Road City Oak Island County Brunswick 6 Directions to project (from nearest major intersection) The project is located at 4570 Long Beach Road in Oak Island 7 Latitude 033°56'28 93"N Longitude 8 Contact person who can answer questions about the project 078003'29 54"W Name Brad Sedgwick,PE Telephone Number H. PERMIT INFORMATION: 1 Specify whether project is (check one) X New Renewal of project (910) 619-9990 Modification Fnrm CWi 1-101 Vi-rcinn 1 00 Panty 1 of d su18 6260J 3,ti- 2 if this application is being submitted as the result of a renewal or modification to an existing permit, list the existing permit number and its issue date (if known) 3 Specify the type of project (check one) Low Density X High Density Redevelop General Permit Other 4 Additional Project Requirements (check applicable blanks) CAMA Major X Sediment/Erosion Control 404/401 Permit NPDES Stormwater Information on required state permits can be obtained by contacting the Customer Service Center at 1-877-623-6748 III. PROJECT INFORMATION 1 In the space provided below, summarize how'stormwater will be treated Also attach a detailed narrative (one to two pages) describing stormwater management for the project Multiple Underground Infiltration Trenches 2 Stormwater runoff from this project drain to the .J River basin 3 Total Project Area 1 033 Acres 4 Project Built Upon Area 725 % 5 How many drainage areas does the project have? 3 6 Complete the following information for each drainage area If there are more than two drainage areas in the project, attach an additional sheet with the information for each area provided in the same format as below Basin Information Total Drainage Basin Drainage Basins A, B & C Stream Name Calf Gully Creek -Receiving Stream Class See attached sheet -Receiving Drainage Area 1 033 ac Existing Impervious* Area Impervious* Area 0 749 ac -Proposed Impervious* Area total 72 5% Surface Area Drainage Basin Drainage Basin -Impervious* On -site Building 10,000 0 sf On -site Asphalt Road 20,836 0 sf See attached sheet On -site Sidewalks 1,784 0 sf Other on -site Off site Total 32,620 0 sf * Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas, sidewalks, gravel areas, etc 410, Form SWU-101 Version 3 99 Page Yof 4 Basm Information Drama a Area "A" Drama e Area "B" Drama a Area "C" Receiving Stream Name Calf Gully Creek Calf Gully Creek Calf Gully Creek Receivmg Stream Class C' �oiS/�6 Drama a Area 0 21 ac 0 1 ac 1 0 38 ac ExistingIm ervaous* Area Proposed Impervious* Area 0 19 ac 0 19 ac 0 36 ac % Impervious* Area total 90 5% 90 5% 94 7% Ian rvaous* Surface Area Drama e Basin Drama e Basin Drainage Basm On -sate Concrete 392 sf 392 sf 1000 sf On -sate Asphalt Road/Parking 5099 sf 5099 sf 10638 sf On -sate Building 3000 sf 3000 sf 4000 sf Other on -sate Off site Total 8491 sf 8491 sf 15638 sf G b- 7 How was the off -site impervious area listed derived? NIA IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS The following italicized deed restrictions and protective covenants are required to be recorded for all subdivisions, out parcels and future development prior to sale of any lot If lot sizes vary significantly, a table listing each lot number, size and the allowable built upon area for each lot must be provided as an attachment The following covenants are intended to ensure ongoing compliance with state management permit number as issued by the Division of Water Quality These covenants my not be changed or deleted without the consent of the State 2 No more than square feet of any lot shall be covered by structures or impervious materials Impervious materials include asphalt, gravel, concrete, brick stone, slate or similar material but do not include wood decking or the water surface of swimming pools 3 Swales shall not be filled in, piped, or altered except as necessary to provide driveway crossings 4 Built -upon area in excess of the permitted amount requires a state stormwater management permit modification prior to construction S All permitted runo f from out parcels or future development shall be directed into the permitted stormwater control system These connections to the stormwater control system shall be performed in a manner that maintains the integrity and performance of the system as permitted By your signature below, you certify that the recorded deed restrictions and protective covenants for this project shall include all the applicable item required above, that the covenants will be binding on all parties and persons claiming under them, that they will run with the land, that the required covenants cannot be changed or deleted without concurrence from the State, and that they will be recorded prior to the sale of any lot V. SUPPLEMENT FORMS The applicable state stormwater management permit supplement form (s) listed below must be submitted for each BMP specified for this project Contact the Stormwater and General Permits Unit at (919) 733-5083 for the status and availability of these forms Form SWU-102 Wet Detention Basin Supplement Form SWU-103 Infiltration Basin Supplement Form SWU-104 Low Density Supplement Form SWU-105 Curb Outlet System Supplement Form SWU-106 Off -Site System Supplement Form SW-107 Underground Infiltration Trench Supplement Form SWU-108 Neuse River Basin Supplement Form SWU-109 Innovative Best Management Practice Supplement Pnrm CWI I-101 VPrcinn -1 QQ Pam- 'I of d VI. SUBMJTTAL REQUIREMENTS Only complete application packages will be accepted and reviewed by the Division of Water Quality (DWQ). A complete package includes all of the items listed below. The complete application package should be submitted to the appropriate DWQ Regional Office. 1 Please indicate that you have provided the following required information by initialing in the space provided next to each item • Original and one copv of the Stormwater Management Permit Application Form • One conv of the applicable Supplement Form(s) for each BMP • Permit application processing fee of $420 (savable to NCDENR) • Detailed narrative description of stormwater treatment/manaaement • Two conies of olans and specifications. includine - Development/Project name - Engineer and firm - Legend - North arrow - Scale - Revision number & date - Mean high water line - Dimensioned property/project boundary - Location map with named streets or NCSR numbers - Original contours, proposed contours, spot elevations, finished floor elevations - Details of roads, drainage features, collection systems, and stormwater control measures - Wetlands delineated, or a note on plans that none exist - Existing drainage (including off -site), drainage easements, pipe sizes, runoff calculations - Drainage areas delineated - Vegetated buffers (where required) Vt. AGENT AUTHORIZATION if you wish to designate authority to another individual or firm so that they may provide information on your behalf, please complete this section Designated agent (individual or firm) JBS Consulting, PA Attention Brad Sedgwick, PE Mailing Address 7332 Cotesworth Dr City Wilmington State NC Zip Phone (910)619-9990 Fax 910 &W--�0 Vlll. APPLICANT'S CERTIFICATION 28405 1, (print or type name of person listed to General Information, item 2) Gerard J Skehan, Manager certify that the information included on this permit application form is, to the best of my knowledge, correct and that the project will be constructed in conformance with the approved plans, that the required deed restrictions and protective cove is will be recorded, and that the proposed project complies with the requirements of 15A NCAC 900 Signature Date a Pnrm q W1 1-101 VPrcinn '3 00 PnoP d of d ty 7- Permit No5W' 066 03-1- (to be provided by DWQ) State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM UNDERGROUND INFILTRATION TRENCH SUPPLEMENT This form may be photocopied for use as an original DWO Stormwater Management Plan Review A complete stormwater management plan submittal includes a stormwater management permit application, an underground infiltration trench supplement for each system, design calculations, and plans and specifications showing all stormwater conveyances and system details I. PROJECT INFORMATION Project Name 4570 Long Beach Road Contact Person Brad Sedgwick. PE Phone Number 910 619-9990 For projects with multiple infiltration systems, a supplement form must be completed for each system This worksheet applies to Trench A in Drainage Area A (from plans) (from Form SWU-101) H. DESIGN INFORMATION (attach supporting calculations/documentation): Soils Report Summary (based upon an actual field investigation and soil borings) Soil Type Yaupon silty clay Infiltration Rate 33 SHWT Elevation 95 Trench Design Parameters Design Volume 6588 Design Storm I Drawdown Time 05 Perforated Pipe Size 10 Perforated Pipe Length 432 No Observation Wells 2 Stone Type (if used) #57 T Stone Void Ratio 40% Trench Elevations (in feet mean sea level) Bottom Elevation 97 Storage/Overflow Elevation 98 m/hr finsl (Seasonal High Water Table elevation) cf 0to10o See S �C21 rRQIy 91'106 4C s i 4e Vet,, - war k n.4 9 -3, &V inch event (15 inch event for SA waters, I inch eventfor others) days inch diameter ft (may be required on a case -by -case basis) finsl JeAO-61 10 fins] z2 Form SWU-107 Rev 3 99 Page 1 of 4 �) 4 l06 & 1)4ev 2- J`w duo OZ4 Trench Dimensions Height 1 ft Length 432 ft Width 3 ft Volume Provided 6 cu ft A-6 M. REQUIRED ITEMS CHECKLIST The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N C Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section 15 A NCAC 2H 1008 Initial in the space provided to indicate that the following design requirements have been met and supporting documentation is attached if the applicant has designated an agent in the Stormwater Management Permit Application Form, the agent may initial below Attach justification if a requirement has not been met Applicants Initials a System is located 50 feet from class SA waters and 30 feet from other surface waters b System is located at least 100 feet from water supply wells c Bottom of system is at least 2 feet above the seasonal high water table d Bottom of the system is 3 feet above any bedrock or impervious soil horizon e Off-line system, runoff in excess of the design volume bypasses the system (bypass detail provided) f <�Jv� - L)4e 4�4 h System is designed to draw down the design storage volume to the proposed bottom elevation under seasonal high water conditions within five days based upon infiltration through the bottom only (a hydrogeologic evaluation may be required) Soils have a minimum hydraulic conductivity of 0 52 inches per hour System is not sited on or in fill material or DWQ approval has been obtained i Plans ensure that the installed system will meet design specifications (constructed or restored) upon initial operation once the project is complete and the entire drainage area is stabilized 1 System is sized to take into account the runoff at the ultimate built -out potential from all surfaces draining to the system, including any off -site drainage k. System is located in a recorded drainage easement for the purposes of operation and maintenance and has recorded access easements to the nearest public right-of-way l System captures and infiltrates the runoff from the first 1 0-inch of rainfall (1 5 inch event for areas draining to SA waters) in Drainage area for the device is less than 5 acres n A pretreatment device (filter strip, grassed swale, sediment trap, etc ) is provided o Trench bottom is covered with a layer of clean sand to an average depth of 4 inches Sides of the infiltration trench are lined with geotextile fabric q Rock used is free of fines (washed stone) and has a large void ratio r Side to bottom area ratio is less than 4 1 s Observation well(s) are provided (case -by -case basis) Form SWU-107 Rev 3 99 Page 2 of 4 I • r � t Vegetated filter is provided for overflow (50 feet for SA waters, 30 feet for other waters) and detail is shown on plans u. A benchmark for checking sediment accumulation is provided IV. UNDERGROUND INMTRATION TRENCH OPERATION AND MAINTENANCE AGREEMENT 1. After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general condition. 2 Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system performance 3. Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth Restore depth to original design depth without over -excavating. Over -excavating may cause the required water table separation to be reduced and may compromise the ability of the system to perform as designed 4 The water level in any monitoring wells will be recorded after a I -inch rainfall event and at least once a month Chromic high water table elevations (within 1 foot of the bottom of the system for a period of three months) shall be reported to DWQ immediately 5. If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original design, specifications. If the system cannot be repaired to perform its design function, other stormwater control devices as allowed by NCAC 2H A000 must be designed, approved and constructed. 6 Remove accumulated sediment from the infiltration system annually or when depth in the unit is reduced to 75% of the ongmal design depth The system shall be restored to the original design depth without over excavating Over -excavating may cause the required water table separation to be reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water quality (i.e. stockpiling near a stormwater t mahnwt device or stream, etc.). A benchmark shall be established in the infiltration system. The benchmark will document the original design depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into accumulated sediments When the depth at the benchmark reads _ 2.5" , the accumulated sediment shall be removed from the system. Form SWU-107 Rev 3 99 Page 3 of 4 I acknowledge and agree by my stgnahrre below that I am responsible for maintaimng the Wmwala mIjeehon Sy9tem in a=rdance with the six 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 Print Name and Title Gerard J. Skehan, Minggr Address ►, Phone• Signatu Note "w legally responsible parry should not be a homeowners associaizon unless more than SO% of the lots have been sold and a resident of the subdivision has been named the president 1, A-�t'e a Notary Public for the State of N.IL Cacn ." , County of do hereby certify that _ CS f4r_A -=► S kel►ar. _._ personally appeared before me this day of 3u,Lr 2ao6 and acknowledge fthe due execution of the forgoing infiltration basin maintenance requirements. Witness my hand and official seal, � W `,���ttsttt8trirtoo ..i R �QTARY m �Z 6C r a �, 0-: � G �. My commission expires 6 - Zest Form SWU-107 Rev 3 99 Page 4 of 4 Permit No S God �ZCS 5y— (to be provided by DWO State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM UNDERGROUND INFILTRATION TRENCH SUPPLEMENT This form may be photocopied for use as an original DWO Stormwater Management Plan Review A complete stormwater management plan submittal includes a stormwater management permit application, an underground infiltration trench supplement for each system, design calculations, and plans and specifications showing all stormwater conveyances and system details I. PROJECT INFORMATION Project Name 4570 Long Beach Road Contact Person Brad Sedawick. PE Phone Number (910) 619-9990 For projects with multiple infiltration systems, a supplement form must be completed for each system This worksheet applies to Trench B in Drainage Area B (from plans) (from Form SWU-101) H. DESIGN INFORMATION (attach supporting calculations/documentation): Soils Report Summary (based upon an actual field investigation and soil borings) Soil Type Yaupon silty clay Infiltration Rate 33 SHWT Elevation 95 Trench Design Parameters Design Volume 6588 Design Storm 1 Drawdown Time 05 Perforated Pipe Size 10 Perforated Pipe Length 432 No Observation Wells 2 Stone Type (if used) #57 Stone Void Ratio 40% Trench Elevations (in feet mean sea level) Bottom Elevation 97 Storage/Overflow Elevation 98 re IOI4l0C in/hr 'Fe-C ay�nC2 fmsl (Seasonal High Water Table elevation) i�i ved' '�1610&,- c f a5scru{pcQ inch event (15 inch event for SA waters, I inch event for others1 " days inch diameter ft (may be required on a case -by -case basis) k t4; r fins] D6 173 l a/� fmsl Form SWU-107 Rev 3 99 Page i of 4 g4/a,�; ,eJ,,I,)- s� g 060S 34- Trench Dimensions Height 1 ft Width 3 ft III. REQUIRED ITEMS CHECKLIST Length 432 ft Volume Provided 659-t cu ft The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N C Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section 15 A NCAC 2H 1008 Initial in the space provided to indicate that the following design requirements have been met and supporting documentation is attached If the applicant has designated an agent in the Stormwater Management Permit Application Form, the agent may initial below Attach justification if a requirement has not been met Applicants Initials Q9 a System is located 50 feet from class SA waters and 30 feet from other surface waters b System is located at least 100 feet from water supply wells c Bottom of system is at least 2 feet above the seasonal high water table QZ- d Bottom of the system is 3 feet above any bedrock or impervious soil horizon e Off-line system, runoff in excess of the design volume bypasses the system (bypass detail U� T provided) f System is designed to draw down the design storage volume to the proposed bottom elevation under seasonal high water conditions within five days based upon infiltration through the bottom only (a hydrogeologic evaluation may be required) g Soils have a minimum hydraulic conductivity of 0 52 inches per hour QL h System is not sited on or in fill material or DWQ approval has been obtained i Plans ensure that the installed system will meet design specifications (constructed or restored) upon initial operation once the project is complete and the entire drainage area is 42 stabilized n J. System is sized to take into account the runoff at the ultimate built -out potential from all surfaces draining to the system, including any off -site drainage k System is located in a recorded drainage easement for the purposes of operation and maintenance and has recorded access easements to the nearest public nght-of way ISystem captures and infiltrates the runoff from the first I 0-inch of rainfall (15 inch event Qv< for areas draining to SA waters) a m Drainage area for the device is less than 5 acres t4 6& n A pretreatment device (filter strip, grassed swale, sediment trap, etc ) is provided o Trench bottom is covered with a layer of clean sand to an average depth of 4 inches ✓� p Sides of the infiltration trench are lined with geotextile fabric q Rock used is free of fines (washed stone) and has a large void ratio r Side to bottom area ratio is less than 4 1 s Observation well(s) are provided (case -by -case basis) Form SWU-107 Rev 3 99 Page 2 of 4 t Vegetated filter is provided for overflow (50 feet for SA waters, 30 feet for other waters) and detail is shown on plans u A benchmark for checking sediment accumulation is provided IV. UNDERGROUND INFILTRATION TRENCH OPERATION AND MAINTENANCE AGREEMENT 1 After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general condition 2 Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system performance 3 Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth Restore depth to original design depth without over -excavating Over -excavating may cause the required water table separation to be reduced and may compromise the ability of the system to perform as designed 4 The water level in any monitoring wells will be recorded after a 1-inch rainfall event and at least once a month Chronic high water table elevations (within 1 foot of the bottom of the system for a period of three months) shall be reported to DWQ immediately 5 If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original design specifications if the system cannot be repaired to perform its design function, other stormwater control devices as allowed by NCAC 2H 1000 must be designed, approved and constructed 6 Remove accumulated sediment from the infiltration system annually or when depth in the unit is reduced to 75% of the original design depth The system shall be restored to the onginal design depth without over excavating Over -excavating may cause the required water table separation to be reduced and may compromise the ability of the system to perform as designed Removed sediment shall be disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water duality (i e stockpiling near a stormwater treatment device or stream, etc ) A benchmark shall be established in the infiltration system The benchmark will document the original design depth so that accurate sediment accumulation readings can be taken The measuring device used to determine the depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into accumulated sediments When the depth at the benchmark reads 2.5" , the accumulated sediment shall be removed from the system. Form SWU-107 Rev 3 99 Page 3 of 4 I acknowledge and agree by my signature below that I am responsible for maintaining the stormwater collection system in accordance with the six 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 Print Name and Title Gerard J Skehan, Manager Address Phone Signatu 2Y Note The legally responsible party should not be a homeowners association unless more than SD% of the lots have been sold and a resident of the subdivision has been named the president 1, A —Drew ?o pep— , a Notary Public for the State of V1 W,' k C"o 1k ,�m _ , County of �6,_,.,:Acw!&O= , do hereby certify that 6 er4rA -3'- g ke6,,, _ personally appeared before me this ,a:z day of 3'u rC , '"oL , and acknowledge the due execution of the forgoing infiltration basin maintenance requirements Witness my hand and official seal, 0 w > NOTARY N U Z'Z 2 PUBLIC Z SEAL My commission expires 6 - �- If y°s 09-20 rj 4, Form SWU-107 Rev 3 99 Page 4 of 4 z- Permit No Tog Q156r6J 3.4 (to be provided by DWQ) State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM UNDERGROUND INFILTRATION TRENCH SUPPLEMENT This form may be photocopied for use as an original DWQ Stormwater Management Plan Review A complete stormwater management plan submittal includes a stormwater management permit application, an underground infiltration trench supplement for each system, design calculations, and plans and specifications showing all stormwater conveyances and system details L PROJECT INFORMATION Project Name 4570 Long Beach Road Contact Person Brad SedgEick. PE Phone Number 910 619-9990 For projects with multiple infiltration systems, a supplement form must be completed for each system This worksheet applies to Trench C in Drainage Area C (from plans) (from Form SWU-101) H. DESIGN INFORMATION (attach supporting calculations/documentation): Soils Report Summary (based upon an actual field investigation and soil horings) pig /014 C Soil Type Yaupon silty clay Infiltration Rate 33 SHWT Elevation 955 Trench Design Parameters Design Volume 12451 Design Storm 1 T� Drawdown Time 05 Perforated Pipe Size 10 Perforated Pipe Length 816 No Observation Wells 2 Stone Type (if used) #57 Stone Void Ratio 40% Trench Elevations (in feet mean sea level) Bottom Elevation 975 Storage/Overflow Elevation 985 in/hr � �✓�&JR �1(v14961 sr fmsl (Seasonal High Water Table elevation k- af inch event (15 inch event for SA waters, I inch event for others) days inch diameter ft (may be required on a case -by -case basis) J,�A(`�f fmst ",j Emil l d ..S( " 90 = 24.5- NWT = 21_5r Form SWU-107 Rev 3 99 Page 1 of 4 4?/6/06- &e V "(/, / z S`Cog d60'834L Trench Dimensions Height 1 ft Length 816 ft Width 3 ft Volume Provided 12462 cu ft M. REQUIRED ITEMS CHECKLIST The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N C Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section 15 A NCAC 2H 1008 Initial in the space provided to indicate that the following design requirements have been met and supporting documentation is attached If the applicant has designated an agent in the Stormwater Management Permit Application Form, the agent may initial below. Attach justification if a requirement has not been met Applicants Initials a System is located 50 feet from class SA waters and 30 feet from other surface waters b System is located at least 100 feet from water supply wells c Bottom of system is at least 2 feet above the seasonal high water table d Bottom of the system is 3 feet above any bedrock or impervious soil horizon e Off-line system, runoff in excess of the design volume bypasses the system (bypass detail provided) System is designed to draw down the design storage volume to the proposed bottom elevation under seasonal high water conditions within five days based upon infiltration through the bottom only (a hydrogeologic evaluation may be required) Soils have a minimum hydraulic conductivity of 0 52 inches per hour System is not sited on or in fill material or DWQ approval has been obtained Plans ensure that the installed system will meet design specifications (constructed or restored) upon initial operation once the project is complete and the entire drainage area is stabilized System is sized to take into account the runoff at the ultimate built -out potential from all surfaces draining to the system, including any off -site drainage k System is located in a recorded drainage easement for the purposes of operation and "t b4 _ maintenance and has recorded access easements to the nearest public right-of-way Form SWU-107 Rev 3 99 System captures and infiltrates the runoff from the first 1 0-inch of rainfall (1 5 inch event for areas draining to SA waters) Drainage area for the device is less than 5 acres A pretreatment device (filter strip, grassed swale, sediment trap, etc ) is provided Trench bottom is covered with a layer of clean sand to an average depth of 4 inches Sides of the infiltration trench are lined with geotextile fabric Rock used is free of fines (washed stone) and has a large void ratio Side to bottom area ratio is less than 4 1 Observation well(s) are provided (case -by -case basis) Page 2 of 4 ri t. Vegetated filter is provided for overflow (50 feet for SA waters, 30 feet for other waters) and detail is shown on plans. u. A benchmark for checking sediment accumulation is provided. IV. UNDERGROUND INFILTRATION TRENCH OPERATION AND MAMENANCE AGREEMENT i After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general condition 2 Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system performance. 3 Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth. Restore depth to original design depth without over -excavating. Over -excavating may cause the required water table separation to be reduced and may compromise the ability of the system to perform as designed 4 The water level in any monitoring wells will be recorded after a I -inch ramfall event and at least once a month Chronic high water table elevations (within 1 foot of the bottom of system for a period of three months) shall be reported to DWQ immediately 5 If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original design specifications If the system cannot be repaired to perform its design function, other stormwater control devices as allowed by NCAC 2H 1000 must be designed, approved and constructed. 6 Remove accumulated sediment from the infiltration system annually or when depth in the unit is reduced to 75% of the original design depth. The system shall be restored to the original design depth without over excavating. Over -excavating may cause the required water table separation to be reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be disposed of in an appropriate manner and shall not be handled in a manner ner that will adversely impact water quality (i.e. stockpiling near a stormwater treatment device or stream, etc.). A benchmark shall be established in the infiltration system. The benchmark will document the original design depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the depth at the benchmark reads 2.5" the aeeamulated se"ent shall be removed from the system. Form SVVU-107 Rev 3 99 Page 3 of 4 I acknowledge and agree by my signature below that I am responsible for maintaining the stormwater collection system in accordance with the six 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. Prmt Name and Title: Gerard J. Eke er t.['.. . Phone: Signatu Note Me 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 l few I to llrrz , a Notary Public for the State of County of I do hereby certify that a personally appeared before me this ? day of S�, ..� a a G ,, and acknowledge the due execution of the forgoing mftltratton basin rnamtenance requirements. Witness my hand and official seal, OVw A o,d''% SSIOAO i } NOTARY N U Z'I pUBLIC � cell My commission expires e' -5 ?.,p r Form SWL -107 Rev 3 99 Page 4 of 4