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HomeMy WebLinkAboutSW8020715_CURRENT PERMIT_20100416STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW�S�DZL� DOC TYPE CURRENT PERMIT APPROVED PLANS ❑ HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE YYYYMMDD I � NC®ENR North Carolina Department of Environment and Division of Water Quality Beverly Eaves Perdue Coleen H, Sullins Governor April 26, 2010 Director Natural Resources Mr. Erik Christofferson, Chief Division of Engineering Services North Carolina Wildlife Resources Commission 1720 Mail Service Center Raleigh, NC 27699-1720 Subject: State Stormwater Management Permit No. SW8 020715MOD Ocean Isle Beach Boating Access Area High Density Commercial Infiltration Basin Project Brunswick County Dear Mr. Christofferson: Dee Freeman Secretary The Wilmington Regional Office received a complete Stormwater Management Permit Application for Ocean Isle Beach Boating Access Area on April 7, 2010. 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, effective September 1, 1995. We are forwarding Permit No. SW8 020715MOD dated April 26, 2010, for the construction of the subject project. This permit shall be effective from the date of issuance until April 3, 2013, 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 thirty (30) 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 Ms. Aisha Lau, or me at (910) 796-7215. Sincerely, Georgett�Cott Stormwater Supervisor Division of Water Quality GDSlahl: S:IWQSISTORMWATERIPERMIT1020715MOD.aprlo cc: Mr. Daniel Cabe Brunswick County Building Inspections Jeff Phillips, Brunswick County Engineering Division of Coastal Management Wilmington Regional Office Central Files Wilmington Regional Office 127 Cardinal Drive Extension, Wilmington, North Carolina 28405 1�TOne 1 Phone: 910-796-72151 FAX: 910-350-20041 Customer Service: 1-877-623.6748 1 Y orth Carolina Internet: www.ncwaterqualify.org A'j���N� l//� An Equal Opportunity 1 AffirmaGvektion Employer '� �/ i State Stormwater Management Systems Permit No. SW8 020715MOD STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT HIGH DENSITY COMMERCIAL 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 Mr. Erik Christofferson and North Carolina Wildlife Resources Commission Ocean Isle Beach Boating Access Area Along NC 904, adjacent to DOT bridge, Ocean Isle Beach, Brunswick County FOR THE construction, operation and maintenance of 3 infiltration basin(s) and the continued operation of 1 infiltration basin in compliance with the provisions of 15A NCAC 2H .1000, effective September 1, 1995 (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 April 3, 2013, and shall be subject to the following specified conditions and limitations: 1. 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 1.6 on page 3 of this permit. The stormwater controls have been designed to handle the runoff from 58,952 square feet of impervious area. 3. These basins must be operated with a 50 foot vegetated filter strip. 4. The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per approved plans. There is no built -upon area allowance for future development. 5. All stormwater collection and treatment systems must be located in either 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. 6. The runoff from all built -upon area within the permitted drainage area of this Page 2 of 7 State Stormwater Managemeht Systems Permit No. SW8 020715MOD project must be directed into the permitted stormwater control system. 7. The following design criteria have been permitted for the infiltration basin and must be provided and maintained at design condition: Basin 1 Basin 2 Basin 3 Basin 4 a. Draina a Area acres: 0.69 0.37 0.05 0.62 Onsite, ft: 30258 16185 2297 27129 Offsite ft: 0 0 0 0 b. Totallmperious Surfaces, ft 26352 13480 1417 17703 c. Desi n Storm, inches: 1.5 1.5 1.5 1.5 d. Basin Depth, feet: 1.3 0.9 0.6 0.85 e. Bottom Elevation, FMSL: 8.7 9 6.5 6.15 f. Bottom Surface Area, W. 2.116 1,787 268 2,365 g. Bypass Weir Elevation, FMSL: 10 9.9 7.1 7 h. Permitted Storage Volume ft3: 3,315 1,821 196 2,288 i. Type of Soil: Fine sand Fine sand Fine sand Fine sand j. Expected Infiltration Rate, inlhr: 5 5.61 0.75 18 k. Seasonal High Water Table, FMSL: 6.2 6.9 4.5 4.15 I. Time to Draw Down, hours: 3.36 1.82 9.52 0.56 m Receiving Stream/River Basin: Intracoastal Waterway / Lumber n. Stream Index Number: 15-25 o. Classification of Water Bod : "SA, HQW" 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, infiltration media, flow spreader, catch basins, piping and vegetated filter. g. A clear access path to the bypass structure must be available at all times. Page 3 of 7 State Stormwater Management Systems Permit No. SW8 020715MOD 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. 6. 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. 7. 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. 8. Access to the stormwater facilities shall be maintained via appropriate recorded 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 development, subdivision, acquisition, lease or sale of any, 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. Prior to the construction of any permitted future areas shown on the approved plans, the permittee shall submit final site layout and grading plans to the Division for approval. 11. A copy of the approved plans and specifications shall be maintained on file by the Permittee at all times. At the time the permit is transferred to a new owner, the permittee shall forward the approved plans to the new owner. 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. Page 4of7 State Stormwater Management Systems Permit No. SW8 020715MOD III, GENERAL CONDITIONS This permit is not transferable to any person or entity 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 completed Name/Ownership Change form to the Division of Water Quality, signed by both parties, and accompanied by the supporting documentation as listed on page 2 of the form. The approval of this request will be considered on its merits and may or may not be approved. 2. The permittee is responsible for compliance with all permit conditions until such time as the Division approves the transfer request. Neither the sale of the project nor the transfer of common area to a third party constitutes an approved transfer of the stormwater permit. 3. 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. 4. 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. 5. 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. 6. 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. 7. The permit remains in force and effect until modified, revoked, terminated, or renewed. The permit may be modified, revoked and reissued or terminated for cause. The filing of a request for a permit modification, revocation and reissuance, renewal or termination does not stay any permit condition. 8. 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. 9. Approved plans and specifications for this project are incorporated by reference and are enforceable parts of the permit. 10. The permittee shall notify the Division in writing of any name, ownership or mailing address changes at least 30 days prior to making such changes. 11. The permittee shall submit a permit renewal application at least 180 days prior to the expiration date of this permit. The renewal request must include the appropriate documentation and the processing fee. Permit issued this the 26th day of April, 2010. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION een ry z)uiiins, wire Page 5 of 7 State Stormwater Management Systems Permit No. SW8 020715MOD Division of Water Quality By Authority of the Environmental Management Commission Ocean Isle Beach Boating Access Area Stormwater Permit No. SW8 020715MOD Brunswick County Designer's Certification 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 6of7 State. Stormwater Management Systems Permit No. SW8 020715MOD 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 project 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 outlet / bypass structure weir elevation is per the approved plan. 6. The outlet / 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- &cuiting 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. 15. All components of the stormwater BMP are located in either recorded common areas or recorded easements. CC" NCDENR-DWQ Regional Office Brunswick County Building Inspections Page 7 of 7 DWQ USE ONLY Date Received Fee Paid Permit Number Gfd�l'�GE�� 7/Hr�S�E� State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICA' 1lorNIM This form nzay be photocopied for use as an original NOV 0 3 2009 1. GENERAL INFORMATION "I 1. Applicants name (specify the name of the corporation, individual, etc. who owns the project): North Carolina Wildlife Resources Commission 2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance): Erik Christofferson, Chief, Division of Engineering Services 3. Mailing Address for person listed in item 2 above: 1720 Mail Service Center City:Raleigh State:NC Zip:27699-1720 Phone: (91.9 ) 707-0150 _ Fax: (919 707T0162 Email:erik.christofferson®ncwildlife.org 4. Project Name (subdivision, facility, or establishment name - should be consistent with project name on plans, specifications, letters, operation and maintenance agreements, etc.): Ocean Isle Beach Boating Access Area 5. Location of Project (street address): Along NC 904, adiacent to DOT bridge, end of Causewav Drive City:Ocean Isle Beach County:Brunswick Zip:28645 6. Directions to project (from nearest major intersection): Site is approximately 1 mile south of the intersection of HWY 904 and 79. Site is located in old road bed_ adjacent to existing DOT bridge 7. Latitude:330 53' 40" N Lon gitude: 780 26' 23" W of project 8. Contact person who can answer questions about the project: Name:Daniel Cabe Telephone Number: (919 ) 218-4149 Email:daniel.cabe@ncwiidlife.org IL PERMIT INFORMATION: 1. Specify whether project is (check one): []New ❑Renewal ®Modification Form SWU-101 Version 09.25.08 Pagel of4 2. If this application is being submitted as the result of a renewal or modification to an existing permit, list the existing permit numberSWB 020715 and its issue date (if known)April 3, 2003 3. Specify the type of project (check one): ❑Low Density ®High Density ❑Redevelop ❑General Permit ❑Universal SMP ❑Other 4. Additional Project Requirements (check applicable blanks; information on required state permits can be obtained by contacting the Customer Service Center at 1-877-623-6748): ®CAMA Major ❑Sedimentation/Erosion Control ❑404/401 Permit ❑NPDES Industrial Stormwater Ill. 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. Stormwater from the parking area flows to one of two splitter boxes. The first 1.5" will _enter an infiltration basin _ with the excesss bypassing to a veg. filter. The stormwater from entrance road will be captured by a drop inlet _ and enter a third splitter box that directs the first 1.5" to an infitration basin and -bypass the rest to a veg. filter. 2. Stormwater runoff from this project drains to the Lumber River basin. 3. Total Property Area: 3.57 acres 4. Total Coastal Wetlands Area: 0.54 acres 5. Total Property Area (3) - Total Coastal Wetlands Area (4) = Total Project Area**:3.03 acres 6. (Total Impervious Area / Total Project Area) X 100 = Project Built Upon Area (BUA):48 % 7. How many drainage areas does the project have?3 New 8. 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. For high density projects, complete the table with one drainage area for each engineered stormwater device. Basin Information Drainage Area 1 Drainage Area 2 Receiving Stream Name Intracoastal Waterway Intracoastal Waterway Stream Class & Index No. SA SA Total Drainage Area (so 30,258 16,185 On -site Drainage Area (so 30,258 16,185 Off -site Drainage Area (so Existing Impervious* Area (so 17,352 8,980 Proposed Impervious*Area (so 26,352 13,480 Impervious* Area (total) 87.1 % 83% Impervious* Surface Area Drainage Area 1 Drainage Area 2 ' On -site Buildings (so On -site Streets (so On -site Parking (so 25,000 12,500 On -site Sidewalks (so 1,352 980 Other on -site (so Off -site (so Total (so: 26,352 13,480 * Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas, sidewalks, gravel areas, etc, **Total project area shall be calculated to exclude Coastal Wetlands front use when calculating the built upon area percentage calculation. This is the area used to calculate overall percent project built upon krea (BUA). Form SWU-101 Version 09.25.08 Page 2 of Additional Drainage Areas Application Item III - 8 4 z r 9 % Basin Intormatioq Drainage Area 3', jWest Drainage Area 4* 1 Receiving Stream Name Intracoastal Waterway Intracoastal Waterway Stream Class & Index No. SA SA Total Drainage Area (sf) 2,297 27,129 On -site Drainage Area (st) 2,297 27,129 Off -site Drainage Area (so Existing Impervious Area (so 1,417 17,703 Proposed Impervious Area (sf) 1,417 17,703 % Impervious Area (total) 61.7% 65.3% Impervious Surface Ared_ Drainage Area 3 jWest Drainage Area 4**i On -Site Buildings (sf) On -Site Streets (sf) - 1,417 15,889 On -Site Parking (sf) 1,814 On -Site Sidewalks (sf) Other On -Site (s Off -Site (s1) Total (sf): 1,417 17,703 ** The previously permitted western drainage area will not be modified except for paving over the existing gravel base. By �f��Q?Opg � , 9. How was the off -site impervious area listed above derived Projects in Union County: Contact the DWQ Central Office staff to check to see if you project is located within a Threatened & Endangered Species watershed that may be subject to more stringent stormwater requirements, IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS One of the following property restrictions and protective covenants are required to be recorded for all subdivisions, outparcels and future development prior to the sale of any Iot. 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. Forms can be downloaded from http://li2o.enr.state.nc.us/su/bmp forms.htm - deed restrictions. Form DRPC-1 High Density Commercial Subdivisions Form DRPC-2 High Density Developments with Outparcels Form DRPC-3 High Density Residential Subdivisions Form DRPC-4 Low Density Commercial Subdivisions Form DRPC-5 Low Density Residential Subdivisions Form DRPC-6 Low Density Residential Subdivisions with Curb Outlets By your signature below, you certify that the recorded property restrictions and protective covenants for this project shall include all the applicable items required in the above form, 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 NC DWQ and that they will be recorded prior to the sale of any Iot. 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 Permitting Unit at (919) 807-6300 for the status and availability of these forms. Forms can be downloaded from http://ii2o.enr.stite.nc.us/su/bmi2 forms.htm. 1 Form SW401-Low Density Form SW401-Curb Outlet System Form SW401-Off-Site System Form SW401-Wet Detention Basin Form SW401-Infiltration Basin Form SW401-Infiltration Trench Form SW401-Bioretention Cell Form SW401-Level Spreader Form SW401-Wetland Form SW401-Grassed Swale Form SW401-Sand Filter Form SW401-Permeable Pavement Form SW401-Cistern Low Density Supplement Curb Outlet System Supplement Off -Site System Supplement Wet Detention Basin Supplement Infiltration Basin Supplement Underground Infiltration Trench Supplement Bioretention Cell Supplement Level Spreader/Filter Strip/Restored Riparian Buffer Supplement Constructed Wetland Supplement Grassed Swale Supplement Sand Filter Supplement Permeable Pavement Supplement Cistern Supplement Dorm S WU-101 Version 09,25.08 Page 3 of 4 VI. SUBMITTAL 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 Office. (Appropriate office may be found by locating project on the interactive online map atlittp://h2o.enr.state.nc.us/suhnsi maps.htnt) Please indicate that you have provided the following required information by initialing in the space provided next to each item. Initials • Original and one copy of the Stormwater Management Permit Application Form • Original and one copy of the Deed Restrictions & Protective Covenants Form (if required as per Part IV above) TT • Original of the applicable Supplement Form(s) and O&M agreement(s) for each BMP l0 LL • Permit application processing fee of $505 (Express: $4,000 for HD, $2,000 for LD) payable to NCDENRZ • Calculations & detailed narrative description of stormwater treatment/management • Copy of any applicable soils report • Two copies of plans and specifications (sealed, signed & dated), including: - 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) VIL AGENT AUTHORIZATION If you wish to designate authority to another individual or firm so that they may provide information on your behalf (such as additional information requests), please complete this section. (ex. designing engineer or firm) Designated agent (individual or firm):Daniel Cabe Mailing Address:1720 Mail City:Raleigh ^_ _ Phone: 919 218-4149 Email:daniel.cabe®ncwildlife.org VII1. APPLICANT'S CERTIFICATION State:NC Zip:27699-1720 Fax: (919 ) 494-3671 1, (print or type name of person listed in General Infornration, item 2) Erik Christofferson 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 covenants will be recorded, nd that the proposed project complies with the requirements of 15A NCAC 2H .1000. _ _ A J Signature: Date: ° lol Form SWU-101 Version 09.25.08 Page 4 of 4 a Permit No. .::5- A eWr,1 7A� (to be provided by DWQ) o�oF W qT FR°c ®� STORMWATER MANAGEMENT PERMIT APPLICATION FORM o Y NCDENR 401 CERTIFICATION APPLICATION FORM INFILTRATION BASIN SUPPLEMENT This form must be filled out, printed and submitted. The Regpired Items Checklist (Part !it) must be printed, filled out and submitted along with all of the required information. !. PROJECT INFORMATION Project Name Ocean Isle Beach BAA Contact Person Daniel Cabe Phone Number 919 218A149 Date 1-Apr-09 Drainage Area Number One (1) - Application, (Northern Drainage Area, Basin 1- Plan Sheets) 1l. DESIGN INFORMATION Site Characteristics Drainage area 30,258.00 ft2 Impervious area 26,352,00 ft2 Percent impervious 0.87 % Design rainfall depth 1.50 in Peak Flow Calculations 1-yr, 24-hr rainfall depth NA in 3-yr;+R"r intensity 10r r i 10.04` inlhr Pre -development 1-yr, 24-hr discharge NA ft3/sec Post -development 'V-�;,.34.brdischarge myrJ 5#*jh 5.95' —ft'/sec Pre/Post 1-yr, 24-hr peak flow control #VALUE! ft'/sec Storage Volume: Non -SA Waters Minimum design volume required ft' Design volume provided rya Storage Volume: SA Waters 1.5" runoff volume 3154"" ft' Pre -development 1-yr, 24-hr runoff volume NA ft3 Post -development 1-yr, 24-hr runoff volume NA ft3 Minimum required volume #VALUE! ft3 Volume provided 3304" ft3 Soils Report Summary Soil type Fine Sand Infiltration rate 5.0— inlhr SHWT elevation 6.20 fmsl Basin Design Parameters Drawdown time Basin side slopes Basin bottom elevation Storage elevation Storage Surface Area Top elevation Basin Bottom Dimensions Basin length Basin width Bottom Surface Area 0.12 days OK 3.00 :1 OK 8.70 fmsl OK 10.00 fmsl 2,984.00 ftz 11.00 fmsl irregular It irregular ft 2.116.00 ft' #VALUE! Form SW441-InMration Basin-Rev.4 Parts I. & II. Design Summary, Page 1 of 2 Permit No. (to be provided by DWQ) Additional Information Maximum runoff to each inlet to the basin? 0.87 ac-in OK Length of vegetative filter for overflow 50.00 ft OK Dstance to structure 350.00 ft OK Distance from surface waters 50,00 ft OK Distance from water supply well(s) >350 ft OK Separation from impervious soil layer NA ft OK Naturally occuring soil above shwt 2.5"` ft OK Bottom covered with 4-in of clean sand? Y (Y or N) OK Proposed drainage easement provided? Y (Y or N) OK Capures all runoff at ultimate build -out? Y (Y or N) OK Bypass provided for larger storms? Y (Y or N) OK Pretreatment device provided Sputter Box Form SW401-Infiltration Basin•Rev.4 Parts I. & II. Design Summary, Page 2 of 2 Permit N (to be provided by DWQ) 111. REQUIRED ITEMS CHECKLIST Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a requirement has not been met, attach justification. Page! Plan Initials Sheet No. Sf4:f Sheets 2 & 3 0::4S6 s ?a9 i . 5V.L& 3 tC- Sheets4,5,&6 1J i ti Sheets 5 & 6 1J� Calcs Pg 2 L Exhibit G 401 Add. Section 1 1. Plans (1" - 50' or larger) of the entire site showing: Design at ultimate build -out, - Off -site drainage (if applicable), .APDelineated drainage basins (include Rational C coefficient per basin), - Basin dimensions, - Pretreatment system, - High flow bypass system, - Maintenance access, - Proposed drainage easement and public right of way (ROW), - Overflow device, and - Boundaries of drainage easement. 2. Partial plan (1" = 30' or larger) and details for the infiltration basin showing: Bypass structure, - Maintenance access, Basin bottom dimensions, Basin cross-section with benchmark for sediment cleanout, - Flow distribution detail for inflow, -Vegetated filter, and - Pretreatment device. 3. Section view of the infiltration basin (1" = 20' or larger) showing: Pretreatment and treatment areas, and Inlet and outlet structures. 4. A table of elevations, areas, incremental volumes & accumulated volumes to verify the volume provided. 5. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The results of the soils report must be verified in the field by DWQ, by completing & submitting the soils investigation request form, County soil maps are not an acceptable source of soils information. 6. A construction sequence that shows how the infitlration basin will be protected from sediment until the entire drainage area is stabilized. 7. The supporting calculations. 1t7�rt.- , 0 & M Agreer 8. A copy of the signed and notarized operation and maintenance (O&M) agreement. NA 9. A copy of the deed restrictions (if required). Form SW401-Infiltration Basin-Rev.4 Page 1 of 1 Part III. Required Items Checklist, Page 1 of 1 d 'w r } ,y , • , !. ' L+ J � 401 Certification Application .Form Infiltration Basin Supplement Drainage Area One (1) Addendum Notes Section 11 Peak Flow Calculations The NC Wildlife is requesting to be vested in the pre -October 1, 2008 rules; therefore, the peals flow was calculated based on the 10-Year storm with a time of concentration of 5 minutes instead of the 1-Year, 24-hr storm. Storage Volume SA Waters * * Pre -October 1, 2009 rules require storage of the first 1.5 inches of rain. Calculations were not completed for the Pre and post conditions. The minimum required volume is contained within the proposed basin. Soils report Summary *** The soils report, Exhibit F, for boring B-2 provides an infiltration rate of 0.04 in/hr. S&ME was contacted to verify the infiltration rate. S&ME replied that the infiltration test was completed in the least hydraulically conductive soil present in the boring. Based on the infiltration rate at boring B-1, of 5.61 in/hr and the infiltration from the previous soils report, Exhibit G, of 18 and 18.5 in/hr, the NCWRC proposes to remove the soil with the low infiltration rate and replace with soil which has a minimum infiltration rate of 5 in/hr. This should be reasonable given the soils available on -site. Construction Sequence . 1. Complete rough grading of parking area, infiltration basin, level spreader, and vegetative filter. 2. Complete fine grading of parking area and access road. Stabilize with compacted ABC stone. 3. Pave parking area and access road. This eliminates sediment available to enter the infiltration basin. 4. While completing 3 above, construct splitter box, forebay, and level spreader. 5. Fine grade infiltration basin, level spreader supply channel, and vegetative filter. 6. Stabilize graded areas with vegetation. Of w"TEA T � °° P NCDENR STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM LEVEL SPREADER, FILTER STRIP AND RESTORED RIPARIAN BUFFER SUPPLEMENT This form must be completely filled out, printed and submitted. DO NOT FORGET TO ATTACH THE REQUIRED ITEMS CHECKLIST AND ALL REQUIRED ITEMS (NEXT WORKSHEET)I I. PROJECT INFORMATION.. . Project name Ocen Isle Beach BAA Contact name Daniel Cabe Phone number 919 218-4149 Date November 6. 2009 Drainage area number One (1) - Application, (Northern Drainage Area, Basin 1 - Plan Sheets) 11 . DESIGN INFORMATION For Level Spreaders Receiving Flow From a BMP Type of BMP Drawdown flow from the BMP cis For Level Spreaders Receiving Flow from the Drainage Area Drainage area 30,258,00 fly Impervious surface area 26,352.00 ft' Percent impervious 87.09 % Rational C coefficient 0.85 C ISI %'Mi ID Peak flow from the 1 inlhr storm 0.59 cis Time of concentration 5.00 min N O V 0, 9 2D09 Rainfall intensity, 1 0-yr storm 1o.o4 inlhr Peak flow from the 10-yr storm 5.93 cfs BY: Where Does the Level Spreader Discharge? To a grassed biorelention cell? (Y or N) To a mulched bioretendon cell? (Y or N) To a wetland? (Y or N) To a filter strip or riparian buffer? Y (Y or N) Please complete filter strip characterization below. Other (specify) Filter Strip or Riparian Buffer Characterization (if applicable) Width of grass Width of dense ground cover Width of wooded vegetation Total width Elevation at downslope base of level lip Elevation at top of bank of the receiving water Slope (from level lip to to top of bank) Are any draws present? Level Spreader Design Forebay surface area Feet of level lip needed per cis Answer "Y' to one of the following: Length based on the 1 inlhr storm? Length based on the 10-yr storm? Length based on the BMP discharge rate? Design flow Is a bypass device provided? Length of the level lip Are level spreaders in series? 20.00 It 30.00 ft ft 50.00 ft 9.67 fmsl 2.40 fmsl 14.54 % Level spreaders must be placed in series. N (Y or N) OK 51.00 sgft 13 ftic% (Y or N) Y (Y or N) (Y or N) 5.95 cis N (Y or N) 78.00 It N (Y or N) OK A bypass device is not needed. Level spreader length OK. Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Paris 1. and II. Design Summary, page 1 of 2 Bypass Channel Design (if applicable) Does the bypass discharge through a welland? Does the channel enter the stream at an angle? Dimensions of the channel (see diagram below): M B W y Peak velocity in the channel during the 10-yr storm Channel lining material M 1 B (Y or N) Do not complete this section of the wAsheet. (Y or N) Do not complete ft section of the workstreeL Do not complete this section of the worksheet. It Do not complete this section of the worksheet. It Do not complete this section of the worksheet. ft Do not complete this section of the worksheet. ft Do riot compete this section of the worksheet. cfs Do not complete this section of the worksheet. Do not complete this section of the worksheat. M Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Pans I. and II, Design Summary, page 2 at 2 III. REQUIRED ITEMS CHECKLIST Please indicate the page or plan sheet numbers where the supporting documentafion can be found. An incomplete submittal package will result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a requirement has not been met, attach justification. Pagel Plan Initials Sheet No. 0 � �- Sheet 2 &3 1. Plans (1" - 50' or larger) of the entire site showing: - Design at ultimate build -out, - Off -site drainage (if applicable), - Delineated drainage basins (include Rational C coefficient per basin), - Forebay (if applicable), - High flow bypass system, - Maintenance access, - Proposed drainage easement and public right of way (ROW), and - Boundaries of drainage easement. LSheets 4,50 2. Plan details (1" = 30' or larger) for the level spreader showing: - Forebay (if applicable), - High flow bypass system, One foot topo lines between the level lip and top of stream bank, Proposed drainage easement, and - Design at ultimate build -out. Sheet 6 3. Section view of the level spreader (1" = 20' or larger) showing: - Underdrain system (if applicable), - Level tip, Upslope channel, and NA; AttachedW - Downslope filter fabric. 4. A date the filter that the type is -stamped photograph of strip clearly shows of vegetation that present. Addendum 5. A construction sequence that shows how the level spreader will be protected from sediment until the entire drainage area is stabilized. 7-�- Section 1 6. The supporting calculations. QAttached 7. A copy of the signed and notarized operation and maintenance (08M) agreement. NA 8. A copy of the deed restrictions (if required). Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Part III, page 1 of 1 c _, 1. 401 Certification Application Form Level Spreader Supplement Drainage Area One (1) Addendum Notes Section H Time of concentration calculations The time of concentration is less than 5 minutes. Standard practice when this occurs is to use a to = 5 min. This is the most conservative value contained in reference material. Filter Strip or Riparian Buffer Characterization Width of Grass: The width of the grass stated as 20' is approximate. Existing dense ground cover already in place will be disturbed only to the extent required to install the level spreader; this area will be reseeded with grass. Slope: The Level Spreader supplement notes state, level spreaders should be placed in series based on the slope of 14.54 %. Compliance with regulations requiring a 50' setback from NHW prohibits placement of additional level spreaders between the level spreader proposed and the waters edge. However, the area immediately down flow of the level spreader has a slope of approximately 5%. Given the infiltration rate of the in -situ soil in the level spreader supply channel and the area immediately down flow of the level spreader minimal water flow is anticipated in the lower extents of the filter strip which is well established vegetation. Notes Section M Item 4 The attached photo is of the existing vegetation in the area of the filter strips for Basin 1 and Basin 2. We did not have a recent photo of the area. One can be provided via email if required. Construction Seauence l . Complete rough grading of parking area, infiltration basin, level spreader, and vegetative filter. 2. Complete fine grading of parking area and access road. Stabilize with compacted ABC stone. 3. Pave parking area and access road. This eliminates sediment available to enter the infiltration basin. 4. While completing 3 above, construct splitter box, forebay, and lcvel spreader. 5. Fine grade infiltration basin, level spreader supply channel, and vegetative filter. 6. Stabilize graded areas with vegetation. �SI.J�'b�d 2/6 of W ATFH ®TA � 'q NCDENR STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM LEVEL SPREADER, FILTER STRIP AND RESTORED RIPARIAN BUFFER SUPPLEMENT This form must be completely tilled out, printed and submitted. DO NOT FORGET TO ATTACH THE REQUIRED ITEMS CHECKLIST AND ALL REQUIRED ITEMS (NEXT WORKSHEET)l 1. PROJECT INFORMATION Project name Ocen We Beach BAA Contact name Daniel Cabe Phone number 919 218A149 Date November6, 2009 Drainage area number Two(2) - Application, (Southern Drainage Area, Basin 2 - Plan Sheets) II. DESIGN INFORMATION For Level Spreaders Receiving Flow From a BMP Type of BMP Drawdown flow from the BMP cis For Level Spreaders Receiving Flow from the Drainage Area Drainage area 16,185.00 fiz Impervious surface area 13,480.00 fe Percent impervious Rational C coefficient 83.29 0.82 °/v CY Peak flow from the 1 inlhr storm 0.30 cfs O •�` Time of concentration Rainfall intensity,l0-yr storm 5.00 min 10.04 inthr ��G Peak flow from the 10-yr storm 3.06 cfs Where Does the Level Spreader Discharge? To a grassed bioretention cell? (Y or N) To a mulched bioretention cell? (Y or N) To a wetland? (Y or N) To a filter strip or riparian buffer? Y (Y or N) Please complete filter strip characterization below. Other (specify) Filter Strip or Riparian Buffer Characterization (if applicable) Width of grass 20.00 ft Width of dense ground cover 30.00 ft Width of wooded vegetation ft Total width 50.00 It Elevation at downslope base of level lip 9.20 fmsl Elevation at top of bank of the receiving water 2,40 fmsl Slope (from level lip to to top of bank) 13.60 % Level spreaders must be placed in series. Are any draws present? N (Y or N) OK Level Spreader Design Forebay surface area 36.00 sq ft OK Feet of level lip needed per cfs 13 ft/cfs Answer "Y" to one of the following: Length based on the 1 inihr storm? (Y or N) Length based on the 10-yr storm? Y (Y or N) Length based on the BMP discharge rate? (Y or N) Design flow 3,08 cis Is a bypass device provided? N (Y or N) A bypass device is not needed. Length of the level lip 40.30 ft Level spreader length OK. Are level spreaders in series? N .(Y or N) Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Parts I. and ll. Design Summary, page 1 of 2 ;, r 5 . f' ,. �_, .. .. .� -1 .. �f.. _. vfif• JET � .f�, _ i � � 1 � . r +ti � ' Bypass Channel Design (if applicable) Does the bypass discharge through a wetland? Does the channel enter the stream at an angle? Dimensions of the channel (see diagram below): M B W y Peak velocity in the channel during the 10-yr storm Channel lining material 1 1--------- (Y or N) Do not compile ft section of the worksheet. (Y or N) Do not complete this section of the waksheet. Do not complete this section of the worksheet. ft Do not complete this section of the worksheet. ft Do not oomplete this section of the workshel. ft Do not complete this section of the workshel. ft Do not complete this section of the wofksheet. M 1 B cis Do not canplete this section of the worksheet Do not complele this section of the worksheel � 1 M Form SW401-Level Spreader, Fifter Strip, Restored Riparian Buffer-Rev.5 Paris I. and IL Design Summary, page 2 of 2 111. REQUIRED ITEMS CHECKLIST Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package wilf result in a request for additional information. This will delay final review and approval of the project.. Initial in the space provided to indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a requirement has not been met, attach justification. Pagel Plan Initials Sheet No. l L Sheet 2 &3 1. Plans (1" - 50' or larger) of the entire site showing: - Design at ultimate build -out, - Off site drainage (if applicable), - Delineated drainage basins (include Rational C coefficient per basin), - Forebay (if applicable), - High flow bypass system, - Maintenance access, - Proposed drainage easement and public right of way (ROW), and - Boundaries of drainage easement. Sheets 7,849 2. Plan details (1" = 30' or larger) for the level spreader showing: - Forebay (if applicable), - High flow bypass system, - One foot topo lines between the level lip and top of stream bank, - Proposed drainage easement, and - Design at ultimate build -out. 4 F� Sheet 9 Attached f2_ Addendum ,V �G Section 2 L�—`—�— Attached NA 3. Section view of the level spreader (1" = 20' or larger) showing: - Underdrain system (if applicable), - Level lip, - Upslope channel, and - Downslope filter fabric. 4. A date -stamped photograph of the filter strip that clearly shows the type of vegetation that is present. 5. A construction sequence that shows how the level spreader will be protected from sediment until the entire drainage area is stabilized. 5. The supporting calculations. 7. A copy of the signed and notarized operation and maintenance (0&M) agreement. 8. A copy of the deed restrictions (if required). Form SW401-Level Spreader, Fitter Strip, Restored Riparian Buffer-Rev.5 Part III, page 1 of 1 401 Certification Application Form Level Spreader Supplement Drainage Area Two (2) Addendum Notes Section U Time of concentration calculations The time of concentration is less than 5 minutes. Standard practice when this occurs is to use a tc = 5 min. This is the most conservative value contained in reference material. Filter Strip or Riparian Buffer Characterization Width of Grass: The width of the grass stated as 20' is approximate. Existing dense ground cover already in place will be disturbed only to the extent required to install the level spreader; this area will be reseeded with grass. Slope: The Level Spreader supplement notes state, level spreaders should be placed in series based on the slope of 13.6 %. Compliance with regulations requiring a 50' setback from N14W prohibits placement of additional level spreaders between the level spreader proposed and the waters edge. However, the area immediately down flow of the level spreader has a slope of approximately 1 %. Given the infiltration rate of the in -situ soil in the level spreader supply channel and the area immediately down flow of the level spreader minimal water flow is anticipated in the lower extents of the filter strip which is well established vegetation. Notes Section II Item 4 The attached photo is of the existing vegetation in the area of the filter strips for Basin I and Basin 2. We did not have a recent photo of the area. One can be provided via email if required. Construction Seauence 1. Complete rough grading of parking area, infiltration basin, level spreader, and vegetative filter. 2. Complete fine grading of parking area and access road. Stabilize with compacted ABC stone. 3. Pave parking area and access road. This eliminates sediment available to enter the infiltration basin. 4. While completing 3 above, construct splitter box, forebay, and level spreader. 5. Fine grade infiltration basin, level spreader supply channel, and vegetative filter. 6. Stabilize graded areas with vegetation. Permit Number: (to be provided by DWQ) Drainage Area Number: Z Filter Strip, Restored Riparian Buffer and Level Spreader Operation and Maintenance Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set location. Any deficient BMP elements noted in the inspection will be corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. Important maintenance procedures: — Immediately after the filter strip is established, any newly planted vegetation will be watered twice weekly if needed until the plants become established (commonly six weeks). o — Once a year, the filter strip will be reseeded to maintain a dense growth of N vegetation C o co — Stable groundcover will be maintained in the drainage area to reduce the sediment load to the vegetation. — Two to three times a year, grass filter strips will be mowed and the clippings harvested to promote the growth of thick vegetation with optimum pollutant removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and may be allowed to grow as tall as 12 inches depending on aesthetic requirements (NIPC,1993). Forested filter strips do not require this type of maintenance. — Once a year, the soil will be aerated if necessary. — Once a year, soil pH will be tested and lime will be added if necessary. After the filter strip is established, it will be inspected quarterly and within 24 hours after every storm event greater than 1.0 inch (or 1.5 inches if in a Coastal County). Records of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem; How I will remediate the problem. The entire filter strip Trash/debris is present. Remove the trash/debris. system The flow splitter device The flow splitter device is Unclog the conveyance and dispose (if applicable) clogged. of anysediment off -site. The flow splitter device is Make any necessary repairs or damaged. replace if damage is too large for repair. Form SWU40I-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3 Page 1 of 3 BMP element: The swale and the level lip The bypass channel The filter strip The receiving water Potential problem: The swale is clogged with sediment. The level lip is cracked, settled, undercut, eroded or otherwise damaged. There is erosion around the end of the level spreader that shows stormwater has bypassed it. Trees or shrubs have begun to grow on the Swale or just downslope of the level lip. Areas of bare soil and/or erosive gullies have formed Turf reinforcement is damaged or ripap is rolling downhill. Grass is too short or too long (if applicable). Areas of bare soil and/or erosive gullies have formed. Sediment is building up on the filter strip. Plants are desiccated Plants are dead, diseased or dying. Nuisance vegetation is choking out desirable species. Erosion or other signs of damage have occurred at the outlet. How I will remediate the problem: Remove the sediment and dispose of it off -site. Repair or replace lip. Regrade the soil to create a berm that is higher than the level lip, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. Remove them. Regrade the soil if necessary to remove the gully, and then reestablish proper erosion control. Study the site to see if a larger bypass channel is needed (enlarge if necessary). After this, reestablish the erosion control material. Maintain grass at a height of approximately three to six inches. Regrade the soil if necessary to remove the gully, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. Remove the sediment and restabilize the soil with vegetation if necessary. Provide lime and a one- time fertilizer application. Provide additional irrigation and fertilizer as needed. Determine the source of the problem: soils, hydrology, disease, etc. Remedy the problem and replace plants. Provide a one-time fertilizer application. Remove vegetation by hand if possible. If pesticide is used, do not allow it to get into the receiving water. Contact the NC Division of Water Quality local Regional Office, or the 401 Oversight Unit at 919-733-1786. Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3 Page 2 of 3 Permit Number: S�ZOp2 Q7Z�— (to he provided by DWQ) I acknowledge and agree by my signature below that I am responsible for the performance of the maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Project name:Ocean Isle Beach BAA BMP drainage area number:Two (2) (Southern, Basin 2) Print name:Erik Christofferson Title:Chief, Division of En ine�erin,g Services _ Address:1720 Mail Service Center Phonc:919 707-0150 , Signature: Date: ( i to Loi Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a resident of the subdivision has been named the president. 1, Lan` - r; a � , ; ,t awrl-.< , a Notary Public for the State of IV ear` hhL��Ac-e�►v(.'�.��Q County of "62n , do hereby certify that personally appeared before me this 44� - day of ��Jn rv.�D�,C , c;�00 , and acknowledge the due execution of the forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements. Witness my hand and official seal, Notary Public Wake County North Carolina Commission Expires 2/26/201 SEAL My commission expires a " 014 — CD.Di 1 Form SWU40I-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev,3 Page 3 of 3 .� + •r � t; .�1 •� }}�� ..b ....ten �t� Y :�r� y 1, '' � Y ' i ° � �; w,f • _'1 � � ` �� •� , ' } c Permit Number:�� (to be provided by DWQ) Drainage Area Number: Filter Strip, Restored Riparian Buffer and Level Spreader Operation and Maintenance Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set location. Any deficient BMP elements noted in the inspection will be yt corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. �� y h p� Important maintenance procedures: o Immediately after the filter strip is established, any newly planted vegeta44 tio s9 will be watered twice weekly if needed until the plants become established �O (commonly six weeks). — Once a year, the filter strip will be reseeded to maintain a dense growth of vegetation — Stable groundcover will be maintained in the drainage area to reduce the sediment load to the vegetation. — Two to three times a year, grass filter strips will be mowed and the clippings harvested to promote the growth of thick vegetation with optimum pollutant removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and may be allowed to grow as tall as 12 inches depending on aesthetic requirements (NIPC,1993). Forested filter strips do not require this type of maintenance. — Once a year, the soil will be aerated if necessary. — Once a year, soil pH will be tested and lime will be added if necessary. After the filter strip is established, it will be inspected quarterly and within 24 hours after every storm event greater than 1.0 inch (or 1.5 inches if in a Coastal County). Records of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: How 1 will remediate the roblem: The entire filter strip Trash/debris is present. Remove the trash/debris. system The flow splitter device The flow splitter device is Unclog the conveyance and dispose (if applicable) clogged. of anysediment off -site. The flow splitter device is Make any necessary repairs or damaged. replace if damage is too large for repair. Form SWU40l-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3 Page 1 of 3 5'� r� 5 Permit Number: (to be provided by DWQ) Drainage Area Number: Infiltration Basin Operation and Maintenance Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set location. Any deficient BMP elements noted in the inspection will be corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. Important maintenance procedures: — The drainage area will be carefully managed to reduce the sediment load to the infiltration basin. — Immediately after the infiltration basin is established, the vegetation will be watered twice weekly if needed until the plants become established (commonly six weeks). — No portion of the infiltration basin will be fertilized after the initial fertilization that is required to establish the vegetation. — The vegetation in and around the basin will be maintained at a height of approximately six inches. After the infiltration basin is established, it will be inspected once a quarter and within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a Coastal County). Records of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: How I will remediate theproblem: The entire BMP Trash/debris is present. Remove the trash/debris. The perimeter of the Areas of bare soil and/or Regrade the soil if necessary to infiltration basin erosive gullies have formed. remove the gully, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. The inlet device: pipe or The pipe is clogged (if Unclog the pipe. Dispose of the swale applicable . sediment off -site. The pipe is cracked or Replace the pipe. otherwise damaged (if applicable). Erosion is occurring in the Regrade the swale if necessary to swale (if applicable). smooth it over and provide erosion control devices such as reinforced turf matting or riprap to avoid future problems with erosion. Form SW401-Infiltration Basin O&M-Rev.3 Page I of 3 BMP element: The forebay The main treatment area The embankment The outlet device The receiving water Potential problem: Sediment has accumulated and reduced the depth to 75% of the original design depth. Erosion has occurred or riprap is displaced. Weeds are present. A visible layer of sediment has accumulated. Water is standing more than 5 days after a storm event. Weeds and noxious plants are growing in the main treatment area. Shrubs or trees have started to grow on the embankment. An annual inspection by an appropriate professional shows that the embankment needs repair. Clogging has occurred. The outlet device is damaged Erosion or other signs of damage have occurred at the outlet. How I will remediate the problem: Search for the source of the sediment and remedy the problem if possible. Remove the sediment and dispose of it in a location where it will not cause impacts to streams or the BMP. Provide additional erosion protection such as reinforced turf matting or riprap if needed to prevent future erosion problems. Remove the weeds, preferably by hand. If pesticides are used, wipe them on the plants rather than Search for the source of the sediment and remedy the problem if possible. Remove the sediment and dispose of it in a Iocation where it will not cause impacts to streams or the BMP. Replace any media that was removed in the process. Revegetate disturbed areas immediately. Replace the top few inches of filter media and see if this corrects the standing water problem. If so, revegetate immediately. If not, consult an appropriate professional for a more extensive repair. Remove the plants by hand or by wiping them with pesticide (do not Remove shrubs or trees immediately. Make all needed repairs. Clean out the outlet device. Dispose of the sediment off -site. Repair or replace the outlet device. Contact the NC Division of Water Quality 401 Oversight Unit at 919- 733-1786. Form SW401-Infiltration Basin O&M-Rev.3 Page 2 of 3 Permit Number: �IiY?i 09, a -7 ( S (t� ided by DWQ) I acknowledge and agree by my signature below that I am responsible for the performance of the maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Project name:Ocean Isle Beach BAA BMP drainage area number:One (1) (Northern, Basin 1) Print name:Erik Christofferson Title:Chief, Division of En ing eering Services Address:1720 Mail Service Center 19 707-0150 Signature: Date: Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a resident of the subdivision has been named the president. allotary Public for the State of d c"ThAleltr�0., County of , do hereby certify that �f %&t� ' e personally appeared before me this L L day of pJ'tr,,� , Q, oc� J , and acknowledge the due execution of the forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements. Witness my hand and official seal, 1 Cynthia •- Public Edwards North • �11 ` - - • tl ✓rrirl�.T .r ��rf�s SISAL My commission expires CZ - aZ 4 * a o 1 ? Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3 Page 3 of 3 A j � V �a i ' � '�' i } f Y� �'y � 1 a S '~ � i. � '� Permit No�_�/'JlSzycx {to be provided by DWQ) ATA STORMWATER MANAGEMENT PERMIT APPLICATION FORM o NCDENR 401 CERTIFICATION APPLICATION FORM INFILTRATION BASIN SUPPLEMENT This form must be filled out, printed and submitted. The Required Items Checklist (Part Ill) must be printed, filled out and submitted along with all of the required information, I. PROJECT INFORMATION Project Name Ocean Isle Beach BAA Contact Person Daniel Cabe Phone Number 919 218A149 Date 1-Apr-09 Drainage Area Number Two (2) - Application, (Southern Drainage Area, Basin 2 - Plan Sheets) li. DESIGN INFORMATION Site Characteristics Drainage area 16,185.00 {� Impervious area 13,480.00 ft2 Percent impervious 0.83 % Design rainfall depth 1.50 in Peak Flow Calculations 1-yr, 24-hr rainfall depth ,r 'lyri r intensity /Q — Yr, 6 • A' VA - Pre -development 1-yr, 24-hr discharge Post -development 1-yrr34 6r discharge my r� Pre/Post 1-yr, 24-hr peak flow control Storage Volume: Non -SA Waters Minimum design volume required Design volume provided Storage Volume: SA Waters 1.5" runoff volume Pre -development 1-yr, 24-hr runoff volume Post -development 1-yr, 24-hr runoff volume Minimum required volume Volume provided Soils Report Summary Soil type Infiltration rate SHWT elevation Basin Design Parameters Drawdown time Basin side slopes Basin bottom elevation Storage elevation Storage Surface Area Top elevation Basin Bottom Dimensions Basin length Basin width Bottom Surface Area NA in 10,04' inlhr NA f131sec 3.08' ft3lsec #VALUE! ft3lsec ft3 ft3 1618" ft3 NA ft3 NA ft3 #VALUE! ft3 1818- ft3 Fine Sand 5.61 inlhr 6.90 fmsl 0.07 days OK 3.00 :1 OK 9.00 fmsl OK 9.90 fmsl 2,260.00 ft' 10.50 fmsl irregular ft }rregular ft 1,787.00 f12 #VALUE! Form SW401-Infiltration Basin-Rev.4 Paris I. & II. Design Summary, Page 1 of 2 N�• .� � . t iy, � � > Permit No. (to be provided by DWQ) Additional Information Maximum runoff to each inlet to the basin? 0.45 ac-in OK Length of vegetative filter for overflow 50.00 ft OK Distance to structure 16.00 ft OK Distance from surface waters 50.00 ft OK Distance from water supply well(s) >100 ft OK Separation from impervious soil layer NA ft OK Naturally occuring soil above Owl 2.10 ft OK Bottom covered with 4-in of clean sand? Y (Y or N) OK Proposed drainage easement provided? Y (Y or N) OK Capures all runoff at ultimate build -out? Y (Y or N) OK Bypass provided for larger storms? Y (Y or N) OK Pretreatment device provided Splitter Box Form SW401-Infiltration Basin-Rev.4 Parts I. & II. Design Summary, Page 2 of 2 Permit No (to be provided by DWQ) Jill. REQUIRED ITEMS CHECKLIST Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to indicate the following design requirements have been met. if the applicant has designated an agent, the agent may initial below. If a requirement has not been met, attach justification. Page/ Plan Initials Sheet No. [� Sheets 2 & 3 1. Plans (1" - 50' or larger) of the entire site showing: Design at ultimate build -out, - Off -site drainage (if applicable), , Get 6 y 'l _--9F Delineated drainage basins (include Rational C coefficient per basin), sf 3 - Basin dimensions, Pretreatment system, - High flow bypass system, - Maintenance access, - Proposed drainage easement and public right of way (ROW), - Overflow device, and - Boundaries of drainage easement. Sheets 7,8,&9 2. Partial plan (1" = 30' or larger) and details for the infiltration basin showing: Bypass structure, - Maintenance access, - Basin bottom dimensions, - Basin cross-section with benchmark for sediment cleanout, Flow distribution detail for inflow, Vegetated filter, and Sheets 8 & 9 - Pretreatment device. 3. Section view of the infiltration basin 0 = 20' or larger) showing: - Pretreatment and treatment areas, and n f e— Inlet and outlet structures. Ca1cs Pg 2 4. A table of elevations, areas, incremental volumes & accumulated volumes to verify the volume provided. �l FL Exhibit G 5. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The results of the soils report must be verified in the field by DWQ, by completing & submitting the soils investigation request form. County soil maps are not an acceptable source of soils information, �L 401 Add, 6. A construction sequence that shows how the infitlration basin will be protected from sediment until the entire drainage area is stabilized. The Section 2 7. supporting calculations. WL 0 & M Agreer ' 8. A copy of the signed and notarized operation and maintenance (0&M) agreement. NA 9, A copy of the deed restrictions (if required). Form SW401-Infiltration Basin-Rev.4 Page 1 of 1 Part III. Required Items Checklist, Page 1 of t { L ` ; ; . � �� . {.- � ws l- � l�� 401 Certification Application Form Infiltration :Basin Supplement Drainage Area Two (2) Addendum Notes Section II Peak Flow Calculations * The NC Wildlife is requesting to be vested in the pre -October 1, 2009 rules; therefore, the peak flow was calculated based on the 10-Year storm with a time of concentration of 5 minutes instead of the 1-Year, 24-hr storm. Storage Volume SA Waters ** Pre -October 1, 2009 rules require storage of the first 1.5 inches of rain. Calculations were not completed for the pre and post conditions. The minimum required volume is contained within the proposed basin. Construction Seauence l . Complete rough grading of parking area, infiltration basin, level spreader, and vegetative filter. 2. Complete fine grading of parking area and access road. Stabilize with compacted ABC stone. 3. Pave parking area and access road. This eliminates sediment available to enter the infiltration basin. 4. While completing 3 above, construct splitter box, forebay, and level spreader. ' 5. Fine grade infiltration basin, level spreader supply channel, and vegetative filter. 6. Stabilize graded areas with vegetation. M Permit Number: (to be provided by DWQ) Drainage Area Number: Z. Infiltration Basin Operation and Maintenance- Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set Iocation. Any deficient BMP elements noted in the inspection will be corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. Important maintenance procedures: — The drainage area will be carefully managed to reduce the sediment load to the infiltration basin. — Immediately after the infiltration basin is established, the vegetation will be watered twice weekly if needed until the plants become established (commonly six weeks). — No portion of the infiltration basin will be fertilized after the initial fertilization that is required to establish the vegetation. — The vegetation in and around the basin will be maintained at a height of approximately six inches. After the infiltration basin is established, it will be inspected once a quarter and within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a Coastal County). Records of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: How 1 will remediate the roblem: The entire BMP Trash/debris is present. Remove the trash/debris. The perimeter of the Areas of bare soil and/or Regrade the soil if necessary to infiltration basin erosive gullies have formed. remove the gully, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. The inlet device: pipe or The pipe is clogged (if Unclog the pipe. Dispose of the swale applicable). sediment off -site. The pipe is cracked or Replace the pipe. otherwise damaged (if a licable). Erosion is occurring in the Regrade the swale if necessary to swale (if applicable), smooth it over and provide erosion control devices such as reinforced turf matting or riprap to avoid future problems with erosion. Form SW40I-infiltration Basin O&M-Rev.3 Page I of 3 BMP element: Potential problerry How I will remediate theproblem: The forebay Sediment has accumulated Search for the source of the and reduced the depth to 75% sediment and remedy the problem if of the original design depth. possible. Remove the sediment and dispose of it in a location where it will not cause impacts to streams or the BMP. Erosion has occurred or Provide additional erosion riprap is displaced. protection such as reinforced turf matting or riprap if needed to revent future erosion problems. Weeds are present. Remove the weeds, preferably by hand. If pesticides are used, wipe them on the plants rather than spraying. The main treatment area A visible layer of sediment Search for the source of the has accumulated. sediment and remedy the problem if possible. Remove the sediment and dispose of it in a location where it will not cause impacts to streams or the BMP. Replace any media that was removed in the process. Revegetate disturbed areas immediately. Water is standing more than Replace the top few inches of filter 5 days after a storm event. media and see if this corrects the standing water problem. If so, revegetate immediately. If not, consult an appropriate professional for a more extensive repair Weeds and noxious plants are Remove the plants by hand or by growing in the main wiping them with pesticide {do not treatment area. spray)-_ The embankment Shrubs or trees have started Remove shrubs or trees to grow on the embankment. immediately. An annual inspection by an Make all needed repairs. appropriate professional shows that the embankment needs repair. The outlet device Clogging has occurred. Clean out the outlet device. Dispose of the sediment off -site. The outlet device is damaged Repair or replace the outlet device. The receiving water Erosion or other signs of Contact the NC Division of Water damage have occurred at the Quality 401 Oversight Unit at 919- outlet. 733-1786. Form SW401-Infiltration Basin O&M-Rev.3 Page 2 of 3 PermitNumber: (to be provided by DWQ) D / r I acknowledge and agree by my signature below that I am responsible for the performance of the maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Project name -.Ocean Isle Beach BAA BMP drainage area number:Two 2 SouthernBasin 2 Print name:Erik Christofferson Title:Chief, Division of Engineering Services Address:1720 Mail Service Center Phone:919 707-0150 Signature: Date: 1� I OA Note: The legally responsible parry 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. I, _ �t!C�+►u�. �.�Q�� , a Notary Public for the State of County of �a., , do hereby certify'that personally appeared before me this day of , ao6iand acknowledge the due execution of the forgoing infiltration basin maintenance requirements. Witness my hand and official seal, Cynthia S. Edwards Notary Public Wake t :ounty North Oarolina Commissic,rr Expires 2/26/2011 SEAL My commission expires a� — Q G - o?U 21 Form SW401-infiltration Basin O&M-Rev.3 Page 3 of 3 V ro, 20 �7l : Permit No. + 5 ��(t be provided by DWQ) 3 oF�ar�9 m O� QG r- �,+ STORMWATER MANAGEMENT PERMIT APPLICATION FORM p NCDENR 401 CERTIFICATION APPLICATION FORM INFILTRATION BASIN SUPPLEMENT This form must be filled out, printed and submitted. The Required Items Checklist (Part !!!) must be printed, filled out and submitted along with all of the required information. I. PROJECT INFORMATION Project Name Ocean Isle Beach SAA Contact Person Daniel Cabe Phone Number 919 218-4149 Date 21-Dec-09 Drainage Area Number Three (3) - Application, (Access Drainage Area, Basin 3 -Plan Sheets) II. DESIGN INFORMATION Site Characteristics Drainage area 2,297.00 ft' Impervious area 1,417.00 it2 Percent impervious 0.62 % Design rainfall depth 1.50 in Peak Flow Calculations 1-yr, 24-hr rainfall depth 1-yr, 24-hr intensity Pre-deveiopment 1-yr, 24-hr discharge Post -development 1-yr, 24-hr discharge PrelPost 1-yr, 24-hr peak flow control Storage Volume: Non -SA Waters Minimum design volume required Design volume provided Storage Volume: SA Waters 1.5" runoff volume Pre -development 1-yr, 24-hr runoff volume Post -development 1-yr, 24-hr runoff volume Minimum required volume Volume provided Soils Report Summary Soil type Infiltration rate SHWT elevation Basin Design Parameters Drawdown time Basin side slopes Basin bottom elevation Storage elevation Storage Surface Area Top elevation Basin Bottom Dimensions Basin length Basin width Bottom Surface Area NA in 44� 10.04* inlhr NA ft3lsec OF 0.35* ft3lsec #VALUE! Wisec ��'• i 2 �'0 W ft3 174** ft3 NA ft3 NA ft3 #VALUE! ft3 195** ft' Fine Sand 0.75 inlhr 4,50 fmsl 0.49 days OK 3,00 :i OK 6.50 fmsl OK 7,10 fmsl 386.00 ft' 7.50 fmsl irregular ft irregular ft 268.00 ftz #VALUE! Form SW401-Infiltration Basin-Rev,4 Paris 1. & II, Design Summary, Page 1 of 2 Permit No. be provided by DWQ) Additional Information Maximum runoff to each inlet to the basin? 0,05 ac-in OK Length of vegetative filter for overflow 50,00 ft OK Distance to structure >100 ft OK Distance from surface waters 200.00 ft OK Distance from water supply wells) >100 ft OK Separation from impervious soil layer NA ft OK Naturally occuring soil above shwt 2.00 ft OK Bottom covered with 4-in of clean sand? Y (Y or N) OK Proposed drainage easement provided? Y (Y or N) OK Capures all runoff at ultimate build -out? Y (Y or N) OK Bypass provided for larger storms? Y (Y or N) OK Pretreatment device provided Splitter Box Form SW401-Infiltrabon Basin-Rev,4 Parts L & II. Design Summary, Page 2 of 2 Permit No. 5 "/ �Q �(to e ded by DWQ) 1 III. REQUIRED ITEMS CHECKLIST Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a requirement has not been met, attach justification. Page/ Plan Initials Sheet No. I Sheets 2 & 3 1. Plans (1" 50' or larger) of the entire site showing: Design at ultimate build -out, Off -site drainage (if applicable), - Delineated drainage basins (include Rational C coefficient per basin), - Basin dimensions, Pretreatment system, High flow bypass system, - Maintenance access, - Proposed drainage easement and public right of way (ROW), - Overflow device, and Boundaries of drainage easement. PLC_ (_ Sh. 10,11,&12 2. Partial plan (1" = 30' or larger) and details for the infiltration basin showing: Bypass structure, - Maintenance access, - Basin bottom dimensions. Basin cross-section with benchmark for sediment cleanout, Flow distribution detail for inflow, Vegetated filter, and - Pretreatment device. Sheets 11 &12 3. Section view of the infiltration basin (1" = 20' or larger) showing: Pretreatment and treatment areas, and Inlet and outlet structures. 1 Calcs Pg 2 4. A table of elevations, areas, incremental volumes & accumulated volumes to verify the volume provided. Attached 5. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The results of the soils report must be verified in the field by DWQ, by completing & submitting the soils investigation request form. County soil maps are not an acceptable source of soils information. 401 Add. 6. A construction sequence that shows how the infitlration basin will be protected from sediment until the entire drainage area is stabilized. dr7 f G Section 3 7. The supporting calculations. P :F L Prev Submittec 8. A copy of the signed and notarized operation and maintenance (O&M) agreement. NA 9. A copy of the deed restrictions (if required). Form 5W401-Infiltration Basin-Rev.4 Page 1 of 1 Part III. Required Items Checklist, Page 1 of 1 401 Certification Application Form Infiltration Basin Supplement Drainage Area Three (3) Addendum Notes Section EI Peak Flow Calculations * The NC Wildlife is requesting to be vested in the pre -October 1, 2008 rules; therefore, the peak flow was calculated based on the 10-Year storm with a time of concentration of 5 minutes instead of the 1-Year, 24-hr storm. Storage Volume SA Waters ** Pre -October 1, 2009 rules require storage of the first 1.5 inches of rain. Calculations were not completed for the Pre and post conditions. The minimum required volume is contained within the proposed basin. Construction Seauence 1. Complete rough grading of parking area, infiltration basin, level spreader, and vegetative filter. 2. Complete fine grading of parking area and access road. Stabilize with compacted ABC stone. 3. Pave parking area and access road. This eliminates sediment available to enter the infiltration basin. 4. While completing 3 above, construct splitter box, forebay, and level spreader. 5. Fine grade infiltration basin, level spreader supply channel, and vegetative filter. b. Stabilize graded areas with vegetation. Permit Number: ��l�� 7/5' (to be provided by DWQ) Drainage Area Number: 3 Infiltration Basin Operation and Maintenance Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set location. Any deficient BMP elements noted in the inspection will be corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. Important maintenance.procedures: — The drainage area will be carefully managed to reduce the sediment load to the infiltration basin. — Immediately after the infiltration basin is established, the vegetation will be watered twice weekly if needed until the plants become established (commonly six weeks). — No portion of the infiltration basin will be fertilized after the initial fertilization that is required to establish the vegetation. — The vegetation in and around the basin will be maintained at a height of approximately six inches. After the infiltration basin is established, it will be inspected once a quarter and within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a Coastal County). Records of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: How 1 will remediate the problerm The entire BMP Trash/debris is present. Remove the trash/debris. The perimeter of the Areas of bare soil and/or Regrade the soil if necessary to infiltration basin erosive gullies have formed. remove the gully, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. The inlet device: pipe or The pipe is clogged (if Unclog the pipe. Dispose of the swale applicable). sediment off -site. The pipe is cracked or Replace the pipe. otherwise damaged (if applicable). Erosion is occurring in the Regrade the swale if necessary to swale (if applicable). smooth it over and provide erosion control devices such as reinforced turf matting or riprap to avoid future problems with erosion. Form SW401-Infiltration Basin O&M-Rev.3 Page 1 of 3 BMP element: Potential roblem: How I will remediate theproblem: The forebay Sediment has accumulated Search for the source of the and reduced the depth to 75% sediment and remedy the problem if of the original design depth. possible. Remove the sediment and dispose of it in a location where it will not cause impacts to streams or the BMP. Erosion has occurred or Provide additional erosion riprap is displaced. protection such as reinforced turf matting or riprap if needed to prevent future erosion problems. Weeds are present. Remove the weeds, preferably by hand. If pesticides are used, wipe them on the plants rather than spraying. The main treatment area A visible layer of sediment Search for the source of the has accumulated. sediment and remedy the problem if possible. Remove the sediment and dispose of it in a location where it will not cause impacts to streams or the BMP. Replace any media that was removed in the process. Revegetate disturbed areas immediately. Water is standing more than Replace the top few inches of filter 5 days after a storm event. media and see if this corrects the standing water problem. If so, revegetate immediately. If not, consult an appropriate professional for a more extensive repair. Weeds and noxious plants are Remove the plants by hand or by growing in the main wiping them with pesticide (do not treatment area. spray). The embankment Shrubs or trees have started Remove shrubs or trees to grow on the embankment. immediately. An annual inspection by an Make all needed repairs. appropriate professional shows that the embankment needs repair. The outlet device Clogging has occurred. Clean out the outlet device. Dispose of the sediment off -site. The outlet device is damaged Repair or replace the outlet device. The receiving water Erosion or other signs of Contact the NC Division of Water damage have occurred at the Quality 401 Oversight Unit at 919- outlet. 733-1786, Form SW401-Infiltration Basin O&M-Rev.3 Page 2 of 3 Permit Number: (5 1' 0 O 220 -7(s' (to / e provided by DWQ) r� 3 I acknowledge and agree by my signature below that I am responsible for the performance of the maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Project name:Ocean Isle Beach BAA BMP drainage area number:Three (3) (Access, Basin 3) Print name:Erik Christofferson Title:Chief. Division of Engineering Services Address:1720 Mail Service Center Phone:919 707-0150 Signature: Date: q'�_ Note: The legally responsible party should not be a homeowners association unless -more than 50% of the lots have been sold and a resident of the subdivision has been named the president. I, W A.r4S , a Notary Public for the State of Kb-f- .,, C•ounty of kkg� , do hereby certify that oG�ci�1d�c~�Or" personally appeared before me this cQ day of , gPj)�!,J , and acknowledge the due execution of the forgoing infiltration basin maintenance requirements. Witness my hand and official seal, Cynthia S. Edwards Notary Public Wake County North Carolina Commissrer Expires 2/26/2011 SEAL My commission expires o?' oZ 41 - oi/D I 1 Form SW401-Infiltration Basin O&M-Rev.3 Page 3 of 3 � J . . . i '. WA 1 NCDENR STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM LEVEL SPREADER, FILTER STRIP AND RESTORED RIPARIAN BUFFER SUPPLEMENT This form must be completely filled out, printed and submitted. DO NOT FORGET TO ATTACH THE REQUIRED ITEMS CHECKLIST AND ALL REQUIRED ITEMS (NEXT WORKSHEET)I I. PROJECT INFORMATION Project name Ocen Isle Beach BAA Contact name Daniel Cabe Phone number 919 218-4149 Date December 18, 2009 Drainage area number Three(3) - Application, (Access Drainage Area, Basin 3 - Plan Sheets) 11. DESIGN INFORMATION For Level Spreaders Receiving Flow From a BMP Type of BMP Drawdown flow from the BMP cfs For Level Spreaders Receiving Flow from the Drainage Area Drainage area 2,297.00 ft2 Impervious surface area 1,417.00 ft' Percent impervious 61,69 Rational C coefficient 0.66: Peak flow from the 1 in/hr storm 0.03 cfs ��C - Time of concentration Rainfall intensity, 10-yr 5.00 min inlhr ,�� storm Peak flow from the 10-yr 10,04 0.35 20 storm cfs Where Does the Level Spreader Discharge 7 To a grassed bioretention cell? (Y or N) To a mulched bioretention cell? (Y or N) To a wetland? (Y or N) To a filter strip or riparian buffer? Y (Y or N) Please complete filter strip characterization below. Other (specify) Filter Strip or Riparian Buffer Characterization (if applicable) Width of grass 50.00 ft Width of dense ground cover 000 ft Width of wooded vegetation ft Total width 50.00 ft Elevation at downslope base of level lip 6.10 fmsl Elevation at top of bank of the receiving water 5,50 fmsi Slope (from level lip to to top of bank) 1.20 % OK Are any draws present? N (Y or N) OK Level Spreader Design Forebay surface area 9.00 sq ft OK Feet of level lip needed per cfs 13 fucfs Answer "Y" to one of the following: Length based on the 1 in/hr storm? (Y or N) Length based on the 10-yr storm? Y (Y or N) Length based on the BMP discharge rate? (Y or N) Design flow 0.35 cfs Is a bypass device provided? N (Y or N) A bypass device is not needed. Form SW461-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Parts I. and H. Design Summary, page 1 of 2 Length of the level lip Are level spreaders in series? ' 13.00 ft Level spreader length OK. N (Y or N) Bypass Channel Design (if applicable) Does the bypass discharge through a wetland? Does the channel enter the stream at an angle? Dimensions of the channel (see diagram below): M B W y Peak velocity in the channel during the 10-yr storm Channel lining material M (Y or N) Do not complete this section of the worksheet. (Y or N) Do not complete this section of the worksheet. Do not complete this section of the worksheet. ft Do not complete this section of the worksheet. ft Do not complete this section of the worksheet. ft Do not complete this section of the worksheet., ft Do not complete this section of the worksheet. cfs Do not complete this section of the worksheet. Do not complete this section of the worksheet. M Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Parts I. and ll. Design Summary, page 2 of 2 III. REQUIRED ITEMS CHECKLIST Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below, If a requirement has not been met, attach justification. Pagel Plan Initials Sheet No. jI f !i Sheet 2 &3 1. Plans (1" - 50' or larger) of the entire site showing: - Design at ultimate build -out, - Off -site drainage (if applicable), - Delineated drainage basins (include Rational C coefficient per basin), - Forebay (if applicable), High flow bypass system, - Maintenance access, Proposed drainage easement and public right of way (ROW), and Boundaries of drainage easement. L Shts.1Q11,&1', 2. Plan details (1" = 30' or larger) for the level spreader showing: Forebay (if applicable), - High flow bypass system, - One foot topo lines between the level lip and top of stream bank, - Proposed drainage easement, and - Design at ultimate build -out. P � L Sheet 12 ALL_ Attached pf L, Addendum Section 3 ti rev. Submittec NA 3. Section view of the level spreader (V = 20' or larger) showing: - Underdrain system (if applicable), - Level lip, - Upslope channel, and - Downslope filter fabric, 4. A date -stamped photograph of the filter strip that clearly shows the type of vegetation that is present. 5. A construction sequence that shows how the level spreader will be protected from sediment until the entire drainage area is stabilized. 6, The supporting calculations. 7. A copy of the signed and notarized operation and maintenance (0&M) agreement. 8. A copy of the deed restrictions (if required). Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Part III, page 1 of 1 401. Certification Application Form Level Spreader Supplement Drainage Area Three (3) Addendum Notes Section II Time of concentration calculations The time of concentration is less than 5 minutes. Standard practice when this occurs is to use a to = 5 min. This is the most conservative value contained in reference material. Notes Section III Item 2 Spot elevations instead of contour lines are provided on Sheet l 1 Construction Sequence 1. Complete rough grading of parking area, infiltration basin, level spreader, and vegetative filter. 2. Complete fine grading of parking area and access road. Stabilize with compacted ABC stone. 3. Pave parking area and access road. This eliminates sediment available to enter the infiltration basin. 4. While completing 3 above, construct splitter box, forebay, and level spreader. S. Fine grade infiltration basin, level spreader supply channel, and vegetative 171 lter. 6. Stabilize graded areas with vegetation. Permit Number:�� S,,aD (to be provided by DIVQ) Drainage Area Number: Filter Strip, Restored Riparian Buffer and Level Spreader Operation and Maintenance Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set location. Any deficient BMP elements noted in the inspection will be corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. Important maintenance procedures: O — Immediately after the filter strip is established, any newly planted vegetation � will be watered twice weekly if needed until the plants become established a (commonly six weeks). `0 — Once a year, the filter strip will be reseeded to maintain a dense growth of o vegetation `O Stable groundcover will be maintained in the drainage area to reduce the sediment load to the vegetation. — Two to three times a year, grass filter strips will be mowed and the clippings harvested to promote the growth of tluck vegetation with optimum pollutant removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and may be allowed to grow as tall as 12 inches depending on aesthetic requirements (NIPC,1993). Forested filter strips do not require this type of maintenance. Once a year, the soil will be aerated if necessary. — Once a year, soil pH will be tested and lime will be added if necessary. After the filter strip is established, it will be inspected quarterly and within 24 hours after every storm event greater than 1.0 inch (or 1.5 inches if in a Coastal County). Records of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: How I will remediate theproblem: The entire filter strip Trash/debris is present. Remove the trash/debris. system The flow splitter device The flow splitter device is Unclog the conveyance and dispose (if applicable) clogged. of anysediment off -site. The flow splitter device is Make any necessary repairs or damaged.' replace if damage is too large for repair. Form SWU40I-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3 rage I of 3 BMP element: The Swale and the level lip The bypass channel The filter strip The receiving water Potential problem: The Swale is clogged with sediment. The level lip is cracked, settled, undercut, eroded or otherwise damaged. There is erosion around the end of the level spreader that shows stormwater has bypassed it. Trees or shrubs have begun to grow on the swale or just downslope of the level lip. Areas of bare soil and/or erosive gullies have formed Turf reinforcement is damaged or ripap is rolling downhill. Grass is too short or too long (if applicable). _ Areas of bare soil and/or erosive gullies have formed. Sediment is building up on the filter strip. Plants are desiccated. Plants are dead, diseased or dying. Nuisance vegetation is choking out desirable species. Erosion or other signs of damage have occurred at the outlet. How I will remediate the problem: Remove the sediment and dispose of it off -site. Repair or replace lip. Regrade the soil to create a berm that is higher than the level lip, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. Remove them. Regrade the soil if necessary to remove the gully, and then reestablish proper erosion control. Study the site to see if a larger bypass channel is needed (enlarge if necessary). After this, reestablish the erosion control material. Maintain grass at a height of approximately three to six inches. Regrade the soil if necessary to remove the gully, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. Remove the sediment and restabilize the soil with vegetation if necessary. Provide lime and a one- time fertilizer application. Provide additional irrigation and fertilizer as needed. Determine the source of the problem: soils, hydrology, disease, etc. Remedy the problem and replace plants. Provide a one-time fertilizer application. Remove vegetation by hand if possible. If pesticide is used, do not allow it to get into the receiving water. Contact the NC Division of Water Quality local Regional Office, or the 401 Oversight Unit at 919-733-1786. Form SWU40I-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3 Page 2 of 3 Permit Number: ��►� �� �/� (to be provided by DWQ) 4 ,' 3 I acknowledge and agree by my signature below that I am responsible for the performance of the maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Project name:Ocean Isle Beach BAA BMP drainage area number:Three (3) (Access, Basin 3) Print name:Erik Christofferson Title:Chief, Division of Engineering Services Address:1720 Mail Service Center Phone Signat Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a resident of the subdivision has been named the president. I, U o. Q W oXI5 , a Notary Public for the State of County of q,O,. , do hereby certify that o personally appeared before me this L day of 96 \/a,yY,6cr , o.oJ, and acknowledge the due execution of the forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements. Witness my hand and official sea], Cynthia S. Edwards Notary Public Wake County North Carolina Commission Expires 2/26/2011 SEAL My commission expires (=�. - of 4 — a 0 11 Form SWU40i-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3 Page 3 of 3 .� r Ocean Isle Beach Boat Access Ramp StorniNvater Permit No. SW8 020715 Brunswick County Designer's Certification State Storr. y ►ter Management Systems Permit No. SW8 020715 I, Daniel E . Dawson , as a duly registered Professional Engineer in the State of North Carolina, having been authorized to observe (periodically/ } the construction of the project, Ocean Isle Beach Boat Access Ramp (Pro j ect) the NC Wildlife Resources Commission 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: Owner must continue to monitor and repair permanent grass. ,NN.. qt. 0 1D357 2 e Signature Registration Number 10357 E►�Pa '��►++Hrn 1l1►N, Date October, 29, 2009 gro� OCZ g � �009 7 State. Ston: iter Management Systems Permit No. SW8 020715 Certification Requirements: l . 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. o� 3.' All the built -upon area associated with the project is graded such that the runoff drains to the system. 4. The outletlbypass structure elevations are per the approved plan. 5. The outlet structure is located per the approved plans. Gem- 6. Trash rack is provided on the outlet/bypass structure. oe),Q 7. All slopes are grassed with permanent vegetation. 8. Vegetated slopes are no steeper than 3:1. of 9. The inlets are located per the approved plans and do not cause short-circuiting of the system. OW10. The pennitted amounts of surface area and/or volume have been provided. 4:P�l 1. Required drawdown devices are correctly sized per the approved plans. ohk 12. All required design depths are provided. �3. All required parts of the system are provided, such as a vegetated shelf, and a forebay. 14. The overall dimensions of the system, as shown on the approved plans, are provided. cc: NCDENR-DWQ Regional Office Ocean Isle Beach Building, Inspections