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HomeMy WebLinkAboutSW8070420_CURRENT PERMIT_20020511STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. Sm U O y ` o DOC TYPE ® CURRENT PERMIT ❑ APPROVED PLANS ❑ HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE 2a22O5►I YYYYMMDD ROY COOPER Governor ELIZABETH S. BISER sec ory BRIAN WRENN Dvector May 11, 2022 Attn: W. K. Morgan Sr., Owner 122 Drayton Hall Jacksonville, NC 28540 NORTH CAROLINA Env& n ntal Qudrty Subject: Permit Renewal Post -Construction Stormwater Management Permit No. SW8 070420 Shopping and Office Park Holly Ridge Onslow County Dear Mr. Morgan: Effective August 1, 2013 the Post -Construction Stormwater Management Program has been transferred from the Division of Walser Quality ("DWQ") to the Division of Energy; Mineral and Land Resources ("DEMLB! ). All previous references to DWQ will remain in older permits issued prior to August 1, 2013 until they are modified. Please note that this permit will now reference DEMLR as the Division responsible for enforcement of the permit. On August 5, 2009, the Governor signed Session Law 2009-406. This law impacted any development approval issued by the former Division of Water Quality under Article 21 of Chapter 143 of the General Statutes, which was current and valid at any point between January 1, 2008, and December 31, 2010. The law extended the effective period. of any permit that was set to expire during this time frame to three (3) years from its current expiration date. On August 2, 2010, the Governor signed Session Law 2010-177, which granted an extra year for a total of four (4) years extension. The Division of Energy, Mineral and Land Resources received a complete 8-year Permit Renewal Application for the subject permit on April 11, 2022. The Division is hereby notifying you that permit SW8070420 has been renewed, updated, and re -issued on May 11, 2022, as attached. Please be aware that the renewal and re -issuance of this stormwa ter permit does not imply that the site is currently in compliance. This permit shall be effective until July 9, 2029, which includes all available extensions, and does not supersede any other agency permit that may be required. The project shall be subject to the conditions and limitations as specified therein. This permit does not impose new or increased stormwater control requirements; it clarifies the rules and requirements of this program to provide you with a better understanding of your obligations under this permit. Failure to comply with these requirements will result in future compliance problems. Please note that this permit is not transferable except after notice to and approval by the Division. If any parts, requirements, or limitations contained in this permit are unacceptable; you have the right to request an adjudicatory hearing by filing a written petition with the Office of Administrative Hearings (OAR). The written petition must conform to Chapter 150B of the North Carolina General Statutes and must be filed with the OAH within thirty (30) days of receipt of this permit. You should contact the OAH with all questions regarding the filing fee (if a filing fee is required) and/or the details of the filing process at 6714 Mail Service Center, Raleigh, NC 27699-6714, or via telephone at 919431-3000, or visit their website at www.NCOAH.com. Unless such demands are made this permit shall be final and binding. If you have any questions concerning this permit, please contact Ashley Smith in the Wilmington Regional Office, at (910) 796-7215 or ashleym.smith@ncdem.gov. Sincerely, C v,-A .7,, Brian Wrenn, Director Division of Energy, Mineral and Land Resources C. / North Carolina Department of Environmental Quality I Division of Energy. Mineral and Land Resources wtlmington Regional office 1127 Cardinal Drive Extension I Wilmington, North Carolina 28405 IQ 910.796.7215 worn reaauN., l State Stormwater Permit No. SW8 070420 Page 2 of 2 Enclosures: Attachment A — Designer's Certification Form Attachment C — Permitting History Renewal Application Documents DES/ams: \\\Stormwater\Permits & Projects\2007\070420 14D\2022 05 permit 070410 cc: Charles F. Riggs, P.L.S.; Charles F. Riggs & Associates, Inc. Land Surveyors; 502 New Bridge Street; Jacksonville, NC 28540 Wilmington Regional Office Stormwater File North Carolina Department of Environmental Quality I Division of Energy, Mneml and Land Resources Wilmington Regional Office 1127 Cardinal Drive Extension I Wilmington. North Carolina 28405 910.796.7215 Post -Construction Stormwater Management Permit No. SW8 070420 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY DIVISION OF ENERGY, MINERAL AND LAND RESOURCES POST -CONSTRUCTION STORMWATER MANAGEMENT PERMIT HIGH DENSITY DEVELOPMENT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws. Rules, and Regulations PERMISSION IS HEREBY GRANTED TO W. K. Morgan, Sr. Shopping & Office Park - Holly Ridge, NC US Highway 17, Holly Ridge, Onslow County FOR THE construction, operation and maintenance of a wet detention pond in compliance with the provisions of 15A NCAC 2H .1000 (hereafter referred to as the "stormwater rules') and as outlined in the application, approved stormwater management plans, supplement, calculations, operation and maintenance agreement, recorded documents, specifications, and other supporting data (the "approved plans and specifications") as attached and/or on file with and approved by the Division of Energy. Mineral and Land Resources (the "Division" or "DEMLR"). The project shall be constructed, operated and maintained in accordance with these approved plans and specifications. The approved plans and specifications are incorporated by reference, and are enforceable part of this permit. This permit shall be effective from the date of issuance until July 9, 2029 and shall be subject to the following specified conditions and limitations. The permit issued shall continue in force and effect until the permittee files a request with the Division for a permit modification, transfer, renewal, or rescission; however, these actions do not stay any condition. The issuance of this permit does not prohibit the Director from reopening and modifying the permit, revoking and reissuing the permit, or terminating the permit for cause as allowed by the laws, rules, and regulations contained in Title 15A NCAC 2H.1000 and NCGS 143-215.1 et.al. I. DESIGN STANDARDS 1. This permit is effective only with respect to the nature and volume of stormwater described in the application and other supporting data. 2. This stormwater system has been approved for the management of stormwater runoff as described in Section 1.6 on page 2 of this permit. The stormwater control has been designed to handle the runoff from 337.097 square feet of impervious area. 3. The tract will be limited to the amount of built -upon area indicated on page 2 of this permit, and per approved plans. The built -upon area for the future development is limited to 8,216 square feet. 4. 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. Page 1 of 7 Post -Construction Stormwater Management Permit No. SW8 070420 5. The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system. 6. The following design criteria have been provided in the wet detention pond and must be maintained at design condition: a. Drainage Area, acres: 12.66 Onsite, ft2: 551.648 Offsite, ft2: None b. Total Impervious Surfaces, ft2: 337,097 C. Design Storm, inches: 1 d. Pond Depth, feet: 6 e. TSS removal efficiency: 90% f. Permanent Pool Elevation, FMSL: 48.00 g. Permanent Pool Surface Area, ft2: 20,024 h. Permitted Storage Volume, ft': 41,016 i. Temporary Storage Elevation, FMSL: 49.88 j. Controlling Orifice: 2.00"0 pipe k. Permitted Forebay Volume, ft': 15,140 I. Fountain Horsepower, HP 1/4 M. Receiving Stream/River Basin: UT King Creek / Cape Fear n. Stream Index Number: 18-87-4 o. Classification of Water Body: "SC, Sw, 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 time provide the operation and maintenance necessary to assure the permitted stormwater system functions at the design condition. 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. G. Mowing and re -vegetation 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 outlet structure, orifice device, flow spreader, catch basins and piping. g. Access to the outlet structure must be available at all times. 4. Records of maintenance activities must be kept and made available upon request to authorized personnel of DEMLR. The records will indicate the date, activity, name of person performing the work and what actions were taken. Decorative spray fountains are allowed in the pond, subject to the following criteria: a. The minimum permanent pool volume is 30,000 cubic feet. b. The fountain must draw its water from less than 2' below the permanent pool surface. C. Separated units, where the nozzle, pump and intake are connected by tubing, may be used only if they draw water from the surface in the deepest part of the pond. d. The fountain may not be placed into the forebay. e. The falling water from the fountain must be centered in the main pond, away from the shoreline. f. The maximum horsepower for a fountain in this pond is 1/4 horsepower. Page 2 of 7 Post -Construction Stormwater Management Permit No. SW8 070420 6. The facilities shall be constructed, operated and maintained in accordance with the provisions of this permit, the approved plans and specifications, and the supporting documents attached to this permit and on file with the Division. 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. 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. 9. Access to the stormwater facilities shall be maintained via appropriate easements at all times. 10. 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. 11. No person or entity, including the permittee, shall alter any component shown in the approved plans and specifications. Prior to the construction of any modification to the approved plans, the permittee shall submit to the Director, and shall have received approval for modified plans, specifications, and calculations including, but not limited to, those listed below. For changes to the project or SCM that impact the certifications, a new or updated certification(s), as applicable, will be required and a copy must be submitted to the appropriate DEQ regional office upon completion of the modification. a. Any modification to the approved plans and specifications, regardless of size including the SCM(s), BUA, details, etc. b. Redesign or addition to the approved amount of BUA or to the drainage area. C. Further development, subdivision, acquisition, lease or sale of any, all or part of the project and/or property area as reported in the approved plans and specifications. d. Altering, modifying, removing, relocating, redirecting, regrading, or resizing of any component of the approved SCM(s), the stormwater collection system and/or vegetative conveyance shown on the approved plan. e. The construction of any allocated future BUA. f. The construction of any permeable pavement, #57 stone area, public trails, or landscaping material to be considered a permeable surface that were not included in the approved plans and specifications. g. Other modifications as determined by the Director. III. GENERAL CONDITIONS 1. CORRECTIVE ACTIONS REQUIRED. If the facilities fail to perform satisfactorily, the permittee shall take immediate corrective actions. This includes actions required by this Division and the stormwater rules such as the construction of additional or replacement on -site stormwater systems. These additional or replacement measures shall receive a permit from the Division prior to construction. 2. PERMIT RENEWAL. A permit renewal request must be submitted at least 180 days prior to the expiration date of this permit. The renewal request must include the appropriate application, documentation and the processing fee as outlined in Title 15A NCAC 02H.'1045(3). 3. CHANGES TO THE PROJECT NAME, PERMIT -TEE NAME OR CONTACT INFORMATION. The permittee shall submit a completed Permit Information Update Application Form to the Division within 30 days to making any one of these changes. Page 3 of 7 Post -Construction Stormwater Management Permit No. SW8 070420 4. TRANSFER. This permit is not transferable to any person or entity except after notice to and approval by the Director. Neither the sale of the project and/or property, in whole or in part, nor the conveyance of common area to a third party constitutes an approved transfer of the permit. TRANSFER REQUEST. The transfer request must include the appropriate application, documentation and the processing fee as outlined in 15A NCAC 02H.1045(2). This request must be submitted within 90 days of the permit holder meeting one or more of the following: i. A natural person who is deceased; ii. A partnership, limited liability corporation, corporation, or any other business association that has been dissolved; iii. A person or entity who has been lawfully and finally divested of title to the property on which the permitted activity is occurring or will occur through foreclosure, bankruptcy, or other legal proceeding. iv. A person or entity who has sold the property, in whole or in part, on which the permitted activity is occurring or will occur. b. TRANSFER INSPECTION. Prior to transfer of the permit, a file review and site inspection will be conducted by Division personnel to ensure the permit conditions have been met and that the project and the on -site stormwater system complies with the permit conditions. Records of maintenance activities performed to date may be requested. Projects not in compliance with the permit will not be transferred until all permit and/or general statute conditions are met. 5. COMPLIANCE. The permittee is responsible for compliance with the terms and conditions of this permit until the Division approves the transfer request. APPROVED PLANS AND SPECIFICATIONS. A copy of this permit, approved plans, application, supplement, operation and maintenance agreement, all applicable recorded documents, and specifications shall be maintained on file by the permittee at all times. DIVISION ACCESS. The permittee grants Division Staff permission to enter the property during normal business hours to inspect all components of the permitted project. C. ENFORCEMENT. Any individual or entity found to be in noncompliance with the provisions of a stormwater management permit or the requirements of the stormwater rules is subject to enforcement procedures as set forth in NCGS 143 Article 21. d. ANNUAL CERTIFICATION. The permittee shall electronically submit to the Division an annual certification completed by either the permittee or their designee confirming the projects conformance with permit conditions e. OBTAINING COMPLIANCE. 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 modified plans and certification in writing to the Director that the changes have been made. f. OTHER PERMITS. The issuance of this permit does not preclude the permittee from complying with and obtaining any other permits or approvals that are required for this development to take place, as required by any statutes, rules, regulations, or ordinances, which may be imposed by any other Local, State or Federal government agency having jurisdiction. Any activities undertaken at this site that cause a water quality violation or undertaken prior to receipt of the necessary permits or approvals to do so are considered violations of NCGS 143-215.1, and subject to enforcement procedures pursuant to NCGS 143-215.6. Page 4 of 7 Post -Construction Stormwater Management Permit No. SW8 070420 Permit renewed, updated and reissued this the 11th day of May 2022. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION WA .T.-.Brian Wrenn, Director Division of Energy, Mineral and Land Resources By Authority of the Environmental Management Commission Permit Number SW8 070420 Page 5 of 7 Post -Construction Stormwater Management Permit No. SW8 070420 Shopping & Office Park - Holly Ridge, NC Stormwater Permit No. SW8 070420 Onslow County Attachment A 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 6 of 7 Post -Construction Stormwater Management Permit No. SWB 070420 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 elevations are per the approved plan. 6. The outlet structure is located per the approved plans. 7. Trash rack is provided on the outlet/bypass structure. 8. All slopes are grassed with permanent vegetation. 9. Vegetated slopes are no steeper than 3:1. 10. The inlets are located per the approved plans and do not cause short-circuiting of the system. 11. The permitted amounts of surface area and/or volume have been provided. 12. Required drawdown devices are correctly sized per the approved plans. 13. All required design depths are provided. 14. All required parts of the system are provided, such as a vegetated shelf, and a forebay. 15. The required system dimensions are provided per the approved plans. cc: NCDEQ-DEMLR Wilmington Regional Office Onslow County Building Inspections Page 7 of 7 Attachment C - Permitting History Shopping and Office Park Holly Ridge Permit No. SW8 070420 Approval Date P rtnit Action BIMS Version Description of the Changes 7/9/2007 Original Approval 1.0 5/1 1/2022 Renewal 2.0 Expires July 9, 2029 DEMLR USE ONLY Date Rec ive Fee Paid Permit Number - y I I ; I ry5� 5CL5 � Sul 070 ,90 NC DEQ Division of Energy, Mineral and Land Resources STATE STORMWATER: PERMIT RENEWAL APPLICATION FORM In accordance with 15A NCAC 2H.1045(3), the current permit holder shall renew their high density permit 180 days prior to its expiration. Renewed permits are valid for a period of 8 years per Session Law 2011-398 (SB 781) Section 60.(c). This application form is for permit renewals only. A. PROJECT INFORMATION 1. State Stormwater Permit Number: 5LAB 0-7042o 2. Project name: L K H.KA4 ;I I _<J!fJq # 0' �IPi�ru. 3. Project stre t addrpss: L1S rl 14H0 17 City: 1� e�I Z 4a. County: 0 0 0� ZIP : 284A 4. What, if any, changes have been made to the project as permitted? h.ICJG If the project has changed from the original approved plans, please complete SWU-101 for a Major Modification or Minor Modification Application form available at: https://deg,nc.gov/about/divisions/energy- m in era I- la nd-resources/ene rqy-minera I -la nd-ru les/stormwater-program/post-construction. B. PERMITTEE INFORMATION If changes to the permittee or project name have been made, please complete either the Permit Update form or the Permit Transfer form available at: https://deg.nc.gov/abouUdivisions/energy-mineral-land- resources/energy-mineral-land-rules/stormwater-program/post-construction. State Stormwater Permits do not automatically transfer with the sale of the property. , 1. Current Permit Holder's Company Name/Organization: In� �"IoZGPt� 2. Signing Official's Name: --- VJ 3. Signing Official's Title: b 4. Mailing Address I 22 City: V J zip: V8540 5. Street Address: ' 'L 1 �A Au" City: ACY=�xv dtl G State: , e- ZIP: 2854-o 6. Phone: (10) 330- W1100 Email: c4oernora nsc 4R!JCE4,1.0-0m 4e�NV�_� APR 1 1 2022 BY: Stormwater Permit Renewal Form Page 1 of 3 May 11, 2018 C. SUBMITTAL REQUIREMENTS Submit the application package to the appropriate DEMLR Regional Office (Coastal, SA Waters) or DEMLR Central Office (Urbanizing Areas Ph 2, USMP, Non -Coastal HQW/ORW). Only applications packages that include all required items listed below will be accepted and reviewed. Initial each item below to indicate that the required information is provided in the application package: 1. A permit application processing fee of $505.00 payable to NCDEQ. 2. One original signed hard copy and one electronic copy of this completed form. The signing official named on this application to represent the current permittee must meet one of the following: a. Corporation — a principle executive officer of at least the level of vice-president; b. Limited Liability Company (LLC) — a manager or company official as those terms are defined in G.S. 57D "North Carolina Limited Liability Company Act," c. Public Entity — a principal executive officer, ranking official, or other duly authorized employee; d. Partnership or limited partnership — the general partner; e. Sole proprietor; or f. Letter of authorization signed by one of the signatories noted in a — e above authorizing the signature of another entity. 3. One hard copy and one electronic copy of recorded documents required by the original permit that have not yet been received by DEMLR, including: deed restrictions, protective covenants, condominium/planned community declaration and easements. If the project has been built, include documentation that the maximum BUA per lot or maximum total BUA has not been exceeded. If the project has not been built, include a signed agreement that the final recorded deed restrictions and protective covenants will be submitted at a later date. 4. O&/KAgreements, Please select one: I have a copy of the current recorded O&M Agreement for all SCMs, and I will continue to keep this on file with the permit; or ❑ I do not have a copy of the current recorded O&M Agreement for all SCMs and am requesting a copy be sent to me. I agree to keep this on file with the permit. 5. Designer Certifications, Please select one: ❑ A copy of the certifications) confirming that the project was built in accordance with the approved plans have been previously provided to the Division; or ❑ A copy of the certification(s) confirming that the project was built in accordance with the approved plans are enclosed; or The project has not yet been built. 6. [IF APPLICABLE] If the project has been built, one original hard copy and one electronic copy of a signed, sealed, and dated letter from a licensed professional stating that the SCMs have been inspected, and that they have been built and maintained in accordance with the permit. 7. [IF APPLICABLE] When the permittee is a corporation or a limited liability corporation (LLC): Provide one hard copy and one electronic copy of documentation from the NC Secretary of State, or other official documentation, which supports the titles and positions held by the persons listed in Section C.2 per 15A NCAC 2H. 1043(3)(b). hdtps://www.sosnc.gov/online services/search/bv title/ Business Registration APR 1 1 2022 BY: Stormwater Permit Renewal Application Form Page 2 of 3 May 11, 2018 D. PERMITTEE'S CERTIFICATION :W'V gpLN ,6e. , the person legally responsible for the permit, certify that I have a copy of the Perrrit_3nd O&M Agreement on site (or I will obtain a copy and it will be kept on site), that I am responsible for the performance of the maintenance procedures, and the site has been and will be maintained according to the O&M Agreement and approved plans. I agree to notify DEMLR of any problems with the SCMs or built -upon area and to submit the proper forms to modify or transfer the permit prior to any changes to the project, SCMs, or ownership. All information provided on this permit renewal application is, to the best of my knowledge, correct and coPjplete. ` 3z / zZ Signature: � Dated/ �[iSr1�Fil\i[� I, RItl5SQ_ Ib..1>yL , a Notary Public for the State of NOrkh Cur0V%rt0• County of O t1510 W do hereby certify that—W. 'k_ mc)y-gq(-\ Sr. personally appeared before me this the e� nd day of MCxrCY1 20 a a, and acknowledge the due execution of the forgoing instrument. Witness my hand and official seal, (Notary Seal) Notary Signature: iYg�b. My commission expires i)700OQy ALYSSA D. DYE NOTARY PUBLIC Onslow County North Carolin Hy Commission Expires IV 1121� _ W_ � _ APR 1 1 2022 BY: Stormwater Permit Renewal Application Form Page 3 of 3 May 11, 2018 Permit No. (to be provided by DWO) State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM WET DETENTION BASIN SUPPLEMENT This form mqv be photocopied for use as an original DWO Stormwat.er Management Plan Review: A complete stormwater management plan submittal includes an application form, a wet detention basin supplement for each basin, design calculations, and plans and specifications showing all basin and outlet structure details. 1. PROJECT INFORMATION Project Name: Shopping & Office Park - Holly Ridge, NC Contact Person: David K.Newsom, PE, Crystal Coast Engineering, PA Phone Number:( 910 ) 325-0006 For projects with multiple basins, specify which basin this workshect applies to: 1 elevations Basin Bottom Elevation 42.00 ft. Permanent Pool Elevation 48.00 ft. Temporary Pool Elevation 49.88 ft. (floor of the basin) (elevation of the orifice) (elevation of the discharge structure overflow) areas Permanent Pool Surface Area 20,024 sq. ft. (hater surface area at the orifice elevation) Drainage Area 12.66 ac. (on -site and off -site drainage to the basin) Impervious Area 7.74 ac. (on -sire and off -site drainage to the basin) volumes Permanent Pool Volume 75,512 cu. ft. (combined volume of main basin andforebay) Temporary Pool Volume 41,016 cu. ft. (volume detained above the permanent pool) Forebay Volume 15,140 cu. ft. (approximately 20% of total volume) Other parameters SAIDA 1 3.4554 (surface area to drainage area ratio from DWQ table) Diameter of Orifice 2.00 in. (2 to 5 day temporary pool draw -down required) Design Rainfall V in. Design TSS Removal 2 90 % (minimum 85% required) FonnSWU-102 Rev3.99 Page I of Footnotes: I When using the Division SA/DA tables, the correct SA/DA ratio for permmncm pool sizing should be computed based upon the actual impervious % and permanent pool depth. Linear interpolation should be employed to determine the correct value for non- standard table entries. 2 In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide 90% TSS removal. The NCDEN R BMP manual provides design tables for both 850, TSS removal and 90% TSS removal. If. REQUIRED ITEMS CHECKLIST The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A NCAC 2H A008. Initial in the space provided to indicate the following design requirements have been met and supporting documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit Application Form, the agent may initial below. If a requirement has not been met, attach justification. Applicants Initials /G a. iJ �G�t/ _ b. C. d. e. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet). The forebay volume is approximately equal to 20% of the basin volume. The temporary pool controls runoff from the design storm event. The temporary pool draws down in 2 to 5 days. If required, a 30-foot vegetative filter is provided at the outlet (include non -erosive flow calculations) The basin length to width ratio is greater than 3:1. The basin side slopes above the permanent pool are no steeper than 3:1. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail). Vegetative cover above the permanent pool elevation is specified. trash rack or similar device is provided for both the overflow and orifice. A recorded drainage easement is provided for each basin including access to nearest right- of-way. 1. If the basin is used for sediment and erosion control during construction, clean out of the ;����� basin is specified prior to use as a wet detention basin. —DA in. A mechanism jc specified which will drain the basin for maintenance or an emergency, l- v ) Ill. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and the vegetated filter if one is provided. This system (check one) 0 does oes not incorporate a vegetated filter at the outlet. This system (check one) 0 doe oes not incorporate pretreatment other than a forebay. Form SW U-102 Rev 3.99 Page 2 of 4 Maintenance activities shall be performed as follows: After every significant runoff producing rainfall event and at least monthly: a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation, vegetated cover, and general condition. b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within 2 to 5 days as designed. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow vegetative cover to maintain a maximum height of six inches, and remove trash as needed. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to maintain proper functioning. Remove accumulated sediment from the wet detention basin system semi-annually or when depth is reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality (i.e. stockpiling near a wet detention basin or stream, etc.). The measuring device used to determine the sediment elevation shall be such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads 4.5 feet in the main pond, the sediment shall be removed. When the permanent pool depth reads 3.75 feet in the forebay, the sediment shall be removed. BASIN DIAGRAM (/ill in the blmtkv) 0 Permanent Pool Elevation 48.00 Sediment Remo al El. 44.25 75�a Sediment Removal Clevation 43.5 75o/p Bottom Elevat on 43.00 2 %--------- ----- Bonom Elevation a 42.00 25% FOREBAY MAIN POND Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These plants shall be encouraged to grow along the vegetated shelf and forebay berm. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment through the emergency drain shall be minimized to the maximum extent practical. Fonn SW U-102 Rev 3.99 Page 3 of 4 7'. 'All components of the wet detention basin system shall be maintained in good working order. I acknowledge and agree by my signature below that I am responsible for the performance of the seven maintenance procedures listed above. 1 agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Print name: t/ . )< . 1�' I Or Qy1 t S (Z Title: =na )\J d ,kod Address: lira bray'+or-\ 1Apd Z-ack66rojt-dc, Nc. o3,90LJ O n,,, -1; t-r tea, r_ 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. , CL�tct C� t11�<�f1%eafY'I , a Notary Public for the State of ml6i'k Ga D� kocu County of do herg1y certify that W K - M Gfc\cW\ , sr - personally appeared before me this � day of A P Rt � 9, DD , and acknowledge the due execution of the forgoing wet detention basin maintenance ruts. W' ess my Kann and cial seal, Lt" ECELIA. CLINKINBEAP.D lic, North Carolina!ew County inirt!nn Eypiroslbtorl0, 2tT 9 SEAL My commission expires NJ D v, I f , a o/ Form S W tJ-102 Rev 3.99 Page 4 of 4