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HomeMy WebLinkAboutSW8921101_CURRENT PERMIT_20210729STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW8 cAl 11 o I DOC TYPE CURRENT PERMIT ❑ APPROVED PLANS ❑ HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE 2021 012°l YYYYMMDD ROY COOPER Governor DIONNE DELLI-GATTI secretary BRIAN WRENN Dbre or July 29, 2021 Marine Corps Base Camp Lejeune Attn: Neal Paul, Deputy Public Works Officer 1005 Michael Road Camp Lejeune, NC 28547 NORTH CAROLINA Emfmnmentaf Quaaty Subject: Permit Renewal State Stormwater Management Permit No. SW8 921101 LHA Simulator/Helicopter Pad Onslow County Dear Mr. Paul: Effective August 1, 2013 the State Stormwater program has been transferred from the Division of Water Quality (DWQ) to the Division of Energy, Mineral and Land Resources (DEMLR). All previous references to DWQ will remain in older stormwater 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 issuance of the permit The Wilmington Regional Office received a complete 8 year Stormwater Management Permit Renewal Application for the subject project on July 27, 2021. The Division is hereby notifying you that permit SW8 921101 has been renewed on July 29, 2021, and shall be effective until January 17, 2029. For your records, please find enclosed a renewed, updated, and re -issued permit and a copy of the renewal application. Please keep this permit on file at all times. Please note that the renewed, updated, and re -issued permit does not impose new or different terms; it merely restates some of the previous terms to provide you with a better understanding of your obligations under the permit. The renewal and reissuance of this stormwater permit does not imply that the site is currently in compliance with the terms and conditions of this state stormwater permit. The plans originally approved on December 16, 1992 and most recently modified on January 17, 2007, will remain in full force and effect in accordance with the regulations set forth in Title 15A NCAC 2H.1000. This permit is subject to the conditions and limitations as specified therein. Please pay special attention to the conditions listed in this permit regarding the Operation and Maintenance of the BMP(s), recordation of deed restrictions, procedures for changes of ownership, transferring the permit, and renewing the permit. Failure to establish an adequate system for operation and maintenance of the stormwater management system, to record deed restrictions, to transfer the permit, or to renew the permit, 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 by filing a written petition with the Office of Administrative Hearings (OAH). 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 919-431-3000, 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, need additional copies of the permit or approved plans, please contact Ashley Smith in the Wilmington Regional Office, at (910) 796-7215 or ashleym.smith@ncdenr.gov. Sincerely, 9.- BriA�4Director":J Division of Energy, Mineral and Land Resources 101.nme t �North Carolina Department of Environmental Quality I Division of Energy. Mineral and Land Resources Wilmington Regional Office 1 127 Cardinal Drive Extension I Wilmington North Carolina 28405 ^��d�®—� 910.796.7245 State Stormwater Permit No. SW8 921101 Page 2 of 2 Enclosures: Attachment A — Designer's Certification Form Attachment C — Permitting History Renewal Application Documents DES/ams: \\\Stormwater\Permits & Projects\1992\921101 HD\2021 07 permit 091101 cc: NCDEQ-DEMLR Wilmington Regional Office ®Ip 0%Z� North Carol'ma Department of Environmental Quality I Division of Energy. Mineral and Land Resources Wilmington Regional Office 1127 Cardinal Drive Extension I Wilmington, North Carolina 28405 �� 910.7%.7215 State Stormwater Management Systems Permit No. SW8 921101 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY DIVISION OF ENERGY, MINERAL AND LAND RESOURCES STATE STORMWATER MANAGEMENT PERMIT HIGH DENSITY DEVELOPMENT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO Commanding General, MCB Camp Lejeune Landing Helicopter Assault (LHA) Deck Off NC 172, 112 mile north of Back Gate, Camp Lejeune, Onslow County FOR THE construction, operation and maintenance of an infiltration basin in compliance with the provisions of 15A NCAC 2H .1000 (hereafter referred to as the "stormwater rules') and the approved stormwater management plans and specifications and other supporting data as attached and on file with and approved by the Division of Energy, Mineral and Land Resources (the "Division" or "DEMLR") and considered an enforceable part of this permit. This permit shall be effective from the date of issuance until January 17, 2029, and shall be subject to the following specified conditions and limitations: I. DESIGN STANDARDS 1. This permit is effective only with respect to the nature and volume of stormwater described in the application and other supporting data. 2. This stormwater system has been approved for the management of stormwater runoff as described in Section 1.6 on page 2 of this permit. The stormwater control has been designed to handle the runoff from 60,940 square feet of impervious area. The infiltration basin must be operated with a 50' vegetated filter. 3. The tract will be limited to the amount of built -upon area indicated on page 2 of this permit, and per approved plans. 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. 5. The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system. Page 1 of 8 State Stormwater Management Systems Permit No. SW8 921101 6. The following design criteria have been provided in the infiltration basin and must be maintained at design condition: a. Drainage Area, acres: Onsite, ftz: Offsite, ftz: b. Total Impervious Surfaces, ftz: c. Design Storm, inches: d. Basin Depth, feet: e. Bottom Elevation, FMSL: f. Bottom Surface Area, ft2: g. Storage Elevation, FMSL: h. Permitted Storage Volume, ft3: i. Type of Soil: j. Expected Infiltration Rate, in/hr: k. Seasonal High Water Table, FMSL: I. Time to Draw Down, hours: M. Receiving Stream/River Basin: n. Stream Index Number: o. Classification of Water Body: II. SCHEDULE OF COMPLIANCE 3.97 173,010 0 60,940 1.5 1.0 92.0 (assumed) 14,033 93.0 14,751 Sand 60 85.0 (assumed) 14 New River / WOK02 19-27 "SA" 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 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: Q 5. 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. 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. 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. Page 2 of 8 State Stormwater Management Systems Permit No. SW8 921101 6. Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to operation of this permitted facility, a certification must be received from an appropriate designer for the system installed certifying that the permitted facility has been installed in accordance with this permit, the approved plans and specifications, and other supporting documentation. Any deviations from the approved plans and specifications must be noted on the Certification. A modification may be required for those deviations. If the stormwater system was used as an Erosion Control device, it must be restored to design condition prior to operation as a stormwater treatment device, and prior to occupancy of the facility. 8. Access to the stormwater facilities shall be maintained via appropriate easements, if needed. at all times. 9. 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. 10. 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. 11. 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. Any items not in compliance must be repaired, replaced restored, or resolved prior to the transfer. Records of maintenance activities performed to date may be requested. III. GENERAL CONDITIONS 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. Page 3 of 8 State Stormwater Management Systems Permit No. SW8 921101 2. 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. 3. 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. 4. Permit Transfer: This permit is not transferable to any person or entity except after notice to and approval by the Director. The permittee shall submit a completed and signed "Permit Transfer Application Form" (available on the Division website) accompanied by the required fee and supporting documentation as listed on the form, to the Division at least 60 days prior to any one or more of the following events: a. The sale or conveyance of the project area in whole or in part, except in the case of an individual lot sale that is made subject to the recorded deed restrictions and protective covenants; b. Dissolution of the partnership, corporate, or LLC entity, subject to NCGS 55-14- 05 or NCGS 57D-6-07 and 08; c. Bankruptcy; d. Foreclosure, subject to the requirements of Session Law 2013-121; 5. Current Permittee Name or Address Changes: The permittee shall submit a completed "Permit Information Update Application Form" (available on the Division website) to the Division within 30 days to making any one or more of the following changes: a. A name change of the current permittee; b. A name change of the project; C. A mailing address change of the permittee; 6. The permittee is responsible for compliance with all terms and conditions of this permit until the Division approves the transfer request. Neither the sale of the project, in whole or in part, nor the conveyance of common area to a third party constitutes an approved transfer of the permit. 7. The permittee grants Division Staff permission to enter the property during normal business hours to inspect all components of the permitted project. 8. 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 permit conditions. 9. Approved plans, application documents, supplements, calculations, operation and maintenance agreement, and specifications for this project are incorporated by reference and are enforceable parts of the permit. A copy of this permit, application, supplements, operation and maintenance agreement, and approved plans and specifications shall be maintained on file by the permittee. 10. Unless specified elsewhere, permanent seeding requirements for the on -site stormwater system must follow the guidelines established in the North Carolina Erosion and Sediment Control Planning and Design Manual. 11. 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 Page 4 of 8 State Stormwater Management Systems Permit No. SW8 921101 allowed by the laws, rules, and regulations contained in Title 15A NCAC 2H.1000 and NCGS 143-215.1 et.al. 12. 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). Permit renewed, updated and reissued this the 29th day of July 2021. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION �7,, Brian�6ir Division of Energy, Mineral and Land Resources By Authority of the Environmental Management Commission Page 5 of 8 State Stormwater Management Systems Permit No. SW8 921101 LHA Deck Stormwater Permit No. SW8 921101 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 8 State Stormwater Management Systems Permit No. SW8 921101 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 bypass structure weir elevation is per the approved plan. 6. The bypass structure is located per the approved plans. 7. A Trash Rack is provided on the bypass structure. 8. All slopes are grassed with permanent vegetation. 9. Vegetated slopes are no steeper than 3:1. 10. The inlets are located per the approved plans and do not cause short- circuiting of the system. 11. The permitted amounts of surface area and/or volume have been provided. 12. All required design depths are provided. 13. All required parts of the system are provided. 14. The required system dimensions are provided per the approved plans. cc: NCDEQ-DEMLR Wilmington Regional Office Page 7 of 8 Attachment C - Permitting History LHA Simulator/Helicopter Launch Pad Permit No. SW8 921101 Approval Date Permit Action BIMS Version Description of the Changes 12/16/1992 Original Approval 1.0 10/l/2004 Plan Revision replacement of existing metal surface with a concrete surface to the same grade and dimensions 1/17/2007 Modification 1.1 7/29/2021 Renewal 2.0 UEMLH USE UNLY ' Date Re eived Fee Paid Permit Number NC DEO 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: SW8 921101 2. Project name: Landing Helicopter Assault (LHA) Deck High Density Project 3. Project street address: XXX City: MCB Camp Leieune County: Onslow ZIP: 28542 4. What, if any, changes have been made to the project as permitted? 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/abouUdivisions/energv- m ine ral-land-resou rces/ene rgy-mineral-land-ru les/stormwate r-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/about/divisions/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: MCB Camp Leieune 2. Signing Official's Name: Neal Paul 3. Signing Official's Title: Deputy Public Works Division 4. Mailing Address: MCB Camp Lejeune 1005 Michael Rd. City: MCB Camp Leieune State: NC ZIP: 28547-2521 5. Street Address: City: State: ZIP 6. Phone: (910) 451-2213 Email: neal.paul@usmc.mil JUL 2 7 2021 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 HOW/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: HEB 1. A permit application processing fee of $505.00 payable to NCDEO. HEB 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 I. Letter of authorization signed by one of the signatories noted in a — e above authorizing the signature of another entity. HEB 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. HEB 4. O&M Agreements, 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. HEB 5. Designer Certifications, Please select one: ® A copy of the certification(s) 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). httos://www.sosnc.gov/online services/search/bv title/ Business Registration JUL 2 7 2021 RV. Stormwater Permit Renewal Application Form Page 2 of 3 May 11, 2018 I' D. PERMITTT/7A E�E_'S10ERTIFICATION I, FOI�� A. /.r>*%,j �w , the person legally responsible for the permit, certify that I have a copy of the Permit and 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 t7inform per forms to modify or transfer the permit prior to any changes to the project, SCMs or ownership. lion provided on this permit renewal application is, to the best of my knowledge, orr ct ind comp te Signature: Date: Zlo z 1 NOTARIZATION: I, E run `�p�(Sp� a Notary Public for the State of moytli+ ('cur&& , County of Di%1Jbu , do hereby certify that RJJ.✓a' K. L-044dl.V' personally appeared before me this the 2-l0 day of 20-L--, and acknowledge the due ,P oi0l;bhgfithe forgoing instrument. Witness y hand and official seal, O° PuByc 'V �o %yk' tarySSig, ts�` i �i �.*.......�..•' 4f""►'i IPOwn expires Irall 7-- JUL 21 2021 Stormwater Permit Renewal Application Form Page 3 of 3 May 11, 2018 Ci Oi� S11 tate of,No'rth,Carolffia Department of Environmenh.and Naturaf-Resources, Dnrsion,of Water Quality. STORN,tf\ :ATER'AQ:aN.AGEN\iEI�,T PERMIT Aa ]?LICtCTIOV'.FOR14 INFILTRATIQN,B.ASIN SUPPLEMENT This, form map be photocopied for"use ai an original MV(D'Stoitnwater''MadaUrinent Plan'Review A complete stor 'water management plan submntal,includesa stonnnater',manage'ment petntiitapplication„an: utf ltraiion basin, supplement for each syntetn desigp, calculations soils report and •plans„and specifications showing`,all stormwatcf conve},,ances and systm d eetails; L, PROJEG7; nFORlt1.aT1ON Proj'ectTa ne'i Landing •Helicopter- Assault Deck, Tli7i-Deck'( 140085-'05' B 6796) Contacr'Person: Carl H. ;Baker, Phone'Domber: "C.9.10)451-2213 .., This i orl heet apPhes m; Basin No., 1 n+Dramage,,?'rea, 1 ic. �r 'ac,rpri,isi_ ,.. rt Sinris ft?rii ❑. DESIGN 11FOR51.ATI0N - attach cupporiing'calculati'oits oocumehtanoti. The soils report musi'bei based upon amactnal,field invmi,zuon and soil borines., County, soil ntnps'are)not jafiracc2l tmble source oEsois infomnuoq, AIl ic%;wions shall be'imfeefinean"sea leveh(fnisl);. Soils Report Summary sod Type Onslm Infiltration Rate 0: 60" ym hn r;cfhr sf, (c r +apDropr'icte uniisy SHWT•Elevation 85: 0" . frnsl (Seosoricb Nigh W ter: Tr.Me'creSciioa? 13asin.D.esign Parameters DesigwStonn 1.5 inch (1.5 •'hch e) enl Gr SA'i oxen, I inch :e,-enmfor orlrers) Desien^volum 1"t.;058. .c.f. Drad down Time 0.25 days 'Basin Dimensions Basirtsize Varies ft �r ,See -Pla14,,033: .. � ns, ft. -.'SQJt `(Otmm dunens.oirs). . Basin Volume Provided 14,751' cif. Basin Elevations Bottom Elevation, 92.0' fmsl. Sto,ra,+e'Elevation, 93.0" Ifillsi. Top Elevation, 93.5' fmsl' ,. Eorm`S R'U.703 Rev.3''.93 (Page Yof. 3 III. 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 .1008. Initial in the space provided to indicate that the following design requirements have been met and supporting documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit Application Form, the agent may initial below. Attach justification if a requirement has not been met. Applicants Initials 1 a. System is located 50 feet from class SA waters and 30 feet from other surface waters. t6 b. System is located at least 100 feet from water supply wells. [� C. Bottom of system is at least 2 feet above the seasonal high water table. r� d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon. 4 e. System is not sited on or in fill material or DWQ approval has been obtained. f. System is located in a recorded drainage easement for the purposes of operation and maintenance and has recorded access casements to the nearest public right-of-way. a g.. Drainage area for the device is less than 5 acres. a. h. Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is attached. i. System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for ^rr areas draining to SA waters ). Design volume and infiltration calculations attached. f j. System is sized to take into account the runoff at the ultimate built -out potential from all surfaces draining to the system, including any off -site drainage. Calculations attached. k. All side slopes stabilized with vegetated cover are no steeper than 3:1 (H:V). CV 1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment trap is provided. �Y m. Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or dense vegetative cover is provided. n. Vegetated filter is provided for overflow and detail is shown on plans (Required minimum length is 50 feet for SA waters, 30 feet for other waters). KV o. Flow distribution mechanism within the basin is provided. a! p. A benchmark is provided to determine the sediment accumulation in the pretreatment device. �✓ q. Runoff in excess of the design volume bypasses off-line systems (bypass detail provided). A` r. System is designed to draw down the design storage volume to the proposed bottom elevation under seasonal high water conditions within five days. A soils report and all pertinent draw -down calculations are attached. s. Plans ensure that the installed system will meet design specifications (constructed or restored) upon initial operation once the project is complete and the entire drainage area is stabilized. Form SWU-103 Rev 3.99 Page 2 of 3 IV. INFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT 1. After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash accumulation, vegetative cover, and general condition. 2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated cover to maintain a maximum height of six inches, and remove trash as needed. 3. After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow structures for blockage and deterioration. Remove any blockage and repair the structure to approved design specifications. 4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original design depth without over -excavating. Over -excavating may cause the required water table separation to be reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water quality (i.e. stockpiling near a stormwater treatment device or stream, etc.). A benchmark shall be established in the pretreatment unit. The benchmark will document the original design depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the design depth reads 0.75 feet in the pretreatment unit, the sediment shall be removed from both the pretreatment unit and the infiltration basin. If the Division determines that the system is failing, the system will immediately be repaired to original design specifications. If the system cannot be repaired to perform its design function, other stormwater control devices as allowed by NCAC 2H .1000 must be designed, approved and constructed. 1 acknowledge and agree by my signature below that I am responsible for the performance of the five maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Print Name and Title: Carl H. Baker, P.E. - Design Director 1005 Michael Road, Camp Lejetme, NC 28547 910-451-2213 4 AL Date: 7 — Z5 no � Note: The legally responsible party should not be a homeowners association unless nrore than 50% of the lots have been sold and a resident of the subdivision has been mmned the president. I, A 1 t C d &I n e. f7h, a Notary Public for the State of A D E 4i C.v. I t do County of On 5 110U.) do hereby certify that 0ay,1. 90.ke U personally appeared before me this LJC day off, QQ , and acknowledge the due execution of the forgoing infiltration basin maintenance requirements. Witness my hand and official seal, I SEAL My commission expires oly 0�g0/O Form SWU-103 Rev 3.99 Page 3 of 3 Permit No. (to be provided by DWQ State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM LOW DENSITY SUPPLEMENT This form may be photocopied for use as an original A low density project is one that meets the appropriate criteria for built upon area and transports stormwater runoff primarily through vegetated conveyances. Low density projects should not have a discrete stormwater collection system as defined by 15A NCAC 2H .1002(18). Low density requirements and density factors can be found in 15A NCAC 2H .1005 through .1007. L PROJECT INFORMATION Project Name: Landing Helicopter Assault Deck, LHA Deck Contact Person: Alex Wood Phone Number: ( 910) 451-5950 ext. 203 Number of Allowable Built Upon Area Per Lot*: 73,260 SF *If lot sizes are not uniform, attach a table indicating the number of lots, lot sizes and allowable built upon area for each lot. The attachment must include the project name, phase, page numbers and provide area subtotals and totals. ❑. BUILT UPON AREA See the Stormwater Management Permit Application for specific language that must be recorded in the deed restrictions for all subdivisions. For uniform lot sizes, complete the following calculation in the space provided below where: • SA Site Area - the total project area above Mean High Water. Wetlands may be excluded when the development results in high density pockets. • DF Density Factor - the appropriate percent built upon area divided by 100. • RA Road Area - the total impervious surface occupied by roadways. • CA Other Area - the total area of impervious surfaces such as clubhouses, tennis courts, sidewalks, etc. • No. Lots - the total number of lots in the subdivision. • BUA/Lot - the computed allowable built upon area for each lot including driveways and impervious surfaces located between the front lot line and the edge of pavement. Form SWU-I04 Rev 3.99 Page I of 2 (SA x DF) - RA - OA = BUA No. Lots Lot Project Drainage Basin = 5.81 AC Proposed Impermeable Area = 1.68 AC % BUA = 1.68 = 28.9% 5.81 Ill. REQUIRED ITEI\IS CHECKLIST Initial in the space provided to indicate that the following requirements have been met and supporting documentation is provided as necessary. If the applicant has designated an agent on the Stonnwater Mana,ement Permit Application Form, the agent may initial below. Applicants Initials 0 a. A 30 foot vegetative buffer is provided adjacent to surface waters. Projects in the Neuse River basin may require additional buffers. Cy b. Deed restriction language as required on form SWU-101 shall be recorded as a restrictive covenant. A copy of the recorded document shall be provided to DWQ within 30 days of platting and prior to sale of any lots. c. Built upon area calculations are provided for the overall project and all lots. d. Project conforms to low density requirements within the ORW AEC (if applicable). [15A NCAC 2H .1007(2)(b)] Fonn SWU-104 Rev 3.99 Pose 2 of 2