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HomeMy WebLinkAboutSW6120706_CURRENT PERMIT_20120822STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW 7�JiD DOC TYPE CURRENT PERMIT r APPROVED PLANS ❑ HISTORICAL FILE DOC DATE �/9�� (ienl� YYYYMMDD ®ENR-FRCS AUG 2 2 2012 NCDENR MID North Carolina Department of Environment and Natural Resources Division of Water Quality Beverly Eaves Perdue Charles Vllakild, PE Dee Freeman Governor Director Secretary August 20, 2012 Mr. David Heins, Environmental Division Chief (DPW) Directorate of Public Works (DPW) 2175 Reilly Road Stop A Fort Bragg, NC 28310 Subject: Stormwater Permit No. SW6120706 SOF Training Facility (Pope) High Density Commercial Wet Pond Project Henderson County Dear Mr. Heins: The Stormwater Permitting Unit received a complete Stormwater Management Permit Application for SOF Training Facility (Pope) on August 15, 2012 after requesting more information on August 3, 2012. 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 and Session Law 2006-246. We are forwarding Permit No. SW6120706, dated August 20, 2012, for the construction, operation and maintenance of the subject project and the stormwater BMPs. This permit shall be effective from the date of issuance until August 19, 2020 and shall be subject to the conditions and limitations as specified therein, and does not supersede any other agency permit that may be required. Please pay special attention to the conditions listed in this permit regarding the Operation and Maintenance of the BMP(s), recordation of deed restrictions, procedure's 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 follow the procedures for transfer of 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 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. This project will be kept on file at the Fayetteville Regional Office. If you have any questions, or need additional information concerning this matter, please contact Brian Lowther at (919) 807-6368; or brian.lowther@ncdenr.gov. Sincerely, for Charles Wakild, PE cc: -Fayetteville_RegionalOffice SW6120706 File ec: Don Higgins — Day & Zimmerman Wetlands and Stormwater Branch 1617 Mail Service Center, Raleigh, North Carolina 27699-1617 Location: 512 N. Salisbury SI Raleigh, North Carolina 27504 Phone: 919-807-63001 FAX: 919-607.6494 .Internet: www,ncwaterquality.org NorthCarolina Naturally An Equal Opponunily 1 Affirmative Action Employer State Stormwater Permit Permit No.SW6120706 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT HIGH DENSITY DEVELOPMENT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO Directorate of Public Works (DPW) SOF Training Facility (Pope) Booster Street, Ft Bragg, Cumberland County FOR THE construction, operation and maintenance of a wet detention pond in compliance with the provisions of 15A NCAC 2H .1000 and S.L. 2006-246 (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 19, 2020, 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 of this permit. The stormwater control has been designed to handle the runoff from 85,748 square feet of impervious area. 3. The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per approved plans. 4. Alf stormwater collection and -treatment systems musfbe 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 6 State Stormwater Permit Permit No.SW6120706 6. The following design criteria have been provided in the wet detention pond and must be maintained at design condition: a. Drainage Area, aps: 5.4 Onsite, ft : 174,250 Offsite, ft2: 60,431 b. Total Impervious Surfaces, ft2: Buildings ft Roads/Parking, ft2: Other, ft2, Offsite, ft C. Pond Depth, feet: d. TSS removal efficiency: e. Design Storm: f. Permanent Pool Elevation, FMS�: g. Permitted Surface Area @PP ft h: Permitted Storage Volume, ft i. Storage Elevation, FMSL: j. Controlling Orifice: k. Permanent Pool Volume, ft3 I. Forebay Volume, ft3: m. Receiving Stream/River Basin: n. Stream Index Number: o. Classification of Water Body II. SCHEDULE OF COMPLIANCE 85,748 14,252 30,042 3,6577 (sidewalks) 3.0 90% 1.0 inch 175.9 11,000 7,500 at temporary pool 176.40 1.5"0 pipe 25,225 5,500 Little River (Lower Little River)/ Cape Fear 18-23-(24) ,1C,o 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_pians_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 DWQ. The records will indicate the date, activity, name of person performing the work and what actions were taken. Page 2 of 6 State Stormwater Permit Permit No.SW6120706 ' 6. Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to operation of this permitted facility, a certification must be received from an appropriate designer for the system installed certifying that the permitted facility has been installed in accordance with this permit, the approved plans and specifications, and other supporting documentation. Any deviations from the approved plans and specifications must be noted on the Certification. A modification may be required for those deviations. 7. if the stormwater system was used as an Erosion Control device, it must be restored to design condition prior to operation as a stormwater treatment device, and prior to occupancy of the facility. 8. Access to the stormwater facilities shall be maintained via appropriate easements at all times. 9. The permittee shall submit to the Director and shall have received approval for revised plans, specifications, and calculations prior to construction, for any modification to the approved plans, including, but not limited to, those listed below: a. Any revision to any item shown on the approved plans, including the stormwater management measures, built -upon area, details, etc. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area or to the drainage area. e. Further subdivision, acquisition, lease or sale of all or part of the project area. The project area is defined as all property owned by the permittee, for which Sedimentation and Erosion Control Plan approval or a CAMA Major permit was sought. f. Filling in, altering, or piping of any vegetative conveyance shown on the approved plan. 10. The permittee shall submit final site layout and grading plans for any permitted future areas shown on the approved plans, prior to construction. 11. A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum of ten years from the date of the completion of construction. 12. The Director may notify the permittee when the permitted site does not meet one or more of the minimum requirements of the permit. Within the time frame specified in the notice, the permittee shall submit a written time schedule to the Director for modifying the site to meet minimum requirements. The permittee shall provide copies of revised plans and certification in writing to the Director that the changes have been made. III. GENERAL CONDITIONS This permit is not transferable except after notice to and approval by the Director. In the event of a change of ownership, or a name change, the permittee must submit a completed Name/Ownership Change form, to the Division of Water Quality, signed by both parties, and accompanied by supporting documentation as listed on page 2 of the form. The project must be in good standing with the Division. 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. Page 3 of 6 State Stormwater Permit Permit No.SW6120706 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 issued shall continue in force and effect until revoked or terminated. The permit may be modified, revoked and reissued or terminated for cause. The filing of a request for a permit modification, revocation and re -issuance 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 issuance of this permit does not prohibit the Director from reopening and modifying the permit, revoking and reissuing the permit, or terminating the permit as allowed by the laws, rules and regulations contained in Session Law 2006- 246, Title 15A NCAC 21-1.1000, and NCGS 143-215.1 et.al. 11. The permittee shall notify the Division of any name,, ownership or mailing address changes at least 30 days prior to making such changes. 12. The permittee shall submit a renewal request with all required forms and documentation at least 180 days prior to the expiration date of this permit. Permit issued this the 20t" day of August, 2012. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION �/ram for Charles Wakild, PE, Director -Division-of-Water-Quality — By Authority of the Environmental Management Commission Page 4 of 6 State Stormwater Permit Permit No.SW6120706 SOF Training Facility (Pope) Stormwater Permit No. SW6120706 Cumberland County Designer's Certification 1, , as a duly registered in the State of North Carolina, having been authorized to observe (periodically/ weekly/ full time) the construction of the project, SOF Training Facility (Pope) (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 5 of 6 State Stormwater Permit , Permit No.SW6120706 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. Please submit this Designer's Certification to: Fayetteville Regional Office Surface Water Protection 225 Green Street Systel-Building-Suite 714 Fayetteville, NC 28301 Page 6 of 6 Ail NCDENR D North Carolina Department of Environment and Natural Resources�J Division of Water Quality bkP Z 4 2012 Beverly Eaves Perdue Charles Wakild, PE MY Freeman Governor Director Secretary August 20, 2012 Mr. David Heins, Environmental Division Chief (DPW) Directorate of Public Works (DPW) 2175 Reilly Road Stop A Fort Bragg, NC 28310 Subject: Stormwater Permit No. SW6120706 SOF Training Facility (Pope) High Density Commercial Wet Pond Project H� County � Dear Mr. Heins: The Stormwater Permitting Unit received a complete Stormwater Management Permit Application for SOF Training Facility (Pope) on August 15, 2012 after requesting more information on August 3, 2012. 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 and Session Law 2006-246. We are forwarding Permit No. SW6120706, dated August 20, 2012, for the construction, operation and maintenance of the subject project and the stormwater BMPs. This permit shall be effective from the date of issuance until August 19, 2020 and shall be subject to the conditions and limitations as specified therein, and does not supersede any other agency permit that may be required. 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 follow the procedures for transfer of 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 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. This project will be kept on file at the Fayetteville Regional Office. If you have any questions, or need additional information concerning this matter, please contact Brian Lowther at (919) 807-6368; or brian.lowther@ncdenr.gov. Sincerely, fbr Charles Wakild, PE CC' Fayetteville Regional Office SW6120706 File ec: Don Higgins — Day & Zimmerman Wetlands and Storrnwaler Branch 1617 Mail Service Center, Raleigh, North Carolina 27699-1617 Location; 512 N. Salisbury St. Raleigh, North Carolina 27604 Phone. 919-807-63001 FAX: 919-807-6494 Internet: www.ncwaterquality.org An Equa Opportunity 1 Alirmative Action Employer NorthCarohna Natumll# State Stormwater Permit Permit No.SW6120706 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT HIGH DENSITY DEVELOPMENT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO Directorate of Public Works (DPW) SOF Training Facility (Pope) Booster Street, Ft Bragg, Cumberland County FOR THE construction, operation and maintenance of a wet detention pond in compliance with the provisions of 15A NCAC 2H .1000 and S.L. 2006-246 (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 19, 2020, 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 of this permit. The stormwater control has been designed to handle the runoff from 85,748 square feet of impervious area. 3. The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per approved plans. 4. All stormwater collection and treatment systems must be located in 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 6 State Stormwater Permit Permit No.SW6120706 - 6. The following design criteria have been provided in the wet detention pond and must be maintained at design condition: a. Drainage Area, aSres: 5.4 Onsite, ft : 174,250 Offsite, ft2: 60,431 b. Total Impervioys Surfaces, ft2: Buildings ft : Roads/Parking, ft2: Other, ft2. Offsite, ft C. Pond Depth, feet: d. TSS removal efficiency: e. Design Storm: f. Permanent Pool Elevation, FMS�: g. Permitted Surface Area @PP ft . h. Permitted Storage Volume, ftl: i. Storage Elevation, FMSL: j. Controlling Orifice: k. Permanent Pool Volume, ft3: I. Forebay Volume, ft3: m. Receiving Stream/River Basin: n. Stream Index Number; o. Classification of Water Body: II. SCHEDULE OF COMPLIANCE 85,748 14,252 30,042 3,6577 (sidewalks) 3.0 90% 1.0 inch 175.9 11,000 7,500 at temporary pool 176.40 1.5" O pipe 25,225 5,500 Little River (Lower Little River)/ Cape Fear 18-23-(24) „C,1 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 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 DWQ. The records will indicate the date, activity, name of person performing the work and what actions were taken. Page 2 of 6 State Stormwater Permit Permit No.SW6120706 6. Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to operation of this permitted facility, a certification must be received from an appropriate designer for the system installed certifying that the permitted facility has been installed in accordance with this permit, the approved plans and specifications, and other supporting documentation. Any deviations from the approved plans and specifications must be noted on the Certification. A modification may be required for those deviations. 7. If the stormwater system was used as an Erosion Control device, it must be restored to design condition prior to operation as a stormwater treatment device, and prior to occupancy of the facility. 8. Access to the stormwater facilities shall be maintained via appropriate easements at all times. 9. The permittee shall submit to the Director and shall have received approval for revised plans, specifications, and calculations prior to construction, for any modification to the approved plans, including, but not limited to, those listed below: a. Any revision to any item shown on the approved plans, including the stormwater management measures, built -upon area, details, etc. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area or to the drainage area. e. Further subdivision, acquisition, lease or sale of all or part of the project area. The project area is defined as all property owned by the permittee, for which Sedimentation and Erosion Control Plan approval or a CAMA Major permit was sought. f. Filling in, altering, or piping of any vegetative conveyance shown on the approved plan. 10. The permittee shall submit final site layout and grading plans for any permitted future areas shown on the approved plans, prior to construction. 11. A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum of ten years from the date of the completion of construction: 12. The Director may notify the permittee when the permitted site does not meet one or more of the minimum requirements of the permit. Within the time frame specified in the notice, the permittee shall submit a written time schedule to the Director for modifying the site to meet minimum requirements. The permittee shall provide copies of revised plans and certification in writing to the Director that the changes have been made. , III. GENERAL CONDITIONS This permit is not transferable except after notice to and approval by the Director. In the event of a change of ownership, or a name change, the permittee must submit a completed Name/Ownership Change form, to the Division of Water Quality, signed by both parties, and accompanied by supporting documentation as listed on page 2 of the form. The project must be in good standing with the Division. 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. Page 3 of 6 State Stormwater Permit Permit No.SW6120706 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 issued shall continue in force and effect until revoked or terminated. The permit may be modified, revoked and reissued or terminated for cause. The filing of a request for a permit modification, revocation and re -issuance 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 issuance of this permit does not prohibit the Director from reopening and modifying the permit, revoking and reissuing the permit, or terminating, the permit as allowed by the laws, rules and regulations contained in Session Law 2006- 246, Title 15A NCAC 2H.1000, and NCGS 143-215.1 et.al. 11. The permittee shall notify the Division of any name, ownership or mailing address changes at least 30 days prior to making such changes. 12.The permittee shall submit a renewal request with all required forms and documentation at least 180 days prior to the expiration date of this permit. Permit issued this the 20th day of August, 2012. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION Jor unarles WaKiia, Fit:, virector Division of Water Quality By Authority of the. Environmental Management Commission Page 4 of 6 State Stormwater Permit Permit No.SW6120706 SOF Training Facility (Pope) Stormwater Permit No. SW6120706 Cumberland Countv 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, SOF Training Facility (Pope) (Project) for best of my abilities, due c construction such that the (Project Owner) hereby state that, to the re and diligence was used in the observation of the project 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 Pabe 5 of 6 State Stormwater Permit Permit No.SW6120706 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. Please submit this Designer's Certification to: Fayetteville Regional Office Surface Water Protection 225 Green Street Systel Building Suite 714 Fayetteville, NC 28301 Page 6 of 6 a NCDENR North Carolina Department of Environment and Natural Resources Division of Water Quality Beverly Eaves Perdue Charles Wakild, P.E. Dee Freeman Governor Director FIECEIVED Secretary August 3, 2012 AUG - l 2012 Mr. Eon Higgins Day Et Zimmerman DENR—FAYETTEVILLE REGIONAL OFFICE 125 The Parkway, Suite 400 Greenville, NC 29615 Subject: Request for Additional Information Stormwater Project No. SW6120706 SOF Training Facility (Pope) Cumberland County Dear Mr. Higgins: The Division of Water Quality Central Office received a request to modify the Stormwater Management Permit for the subject project on July 27, 2012. A preliminary review of that information has determined that the application is not complete. The following information is needed to continue the stormwater review: 1. The permanent pool (PP) elevation should be within 6 inches of the seasonal high water table (SHWT). The supplement indicates the PP is lower than SHWT white the plans indicate the PP is able the SHWT. Please revise the design and fix any inconsistencies. Also, I could not locate the SHWT in the soils report. 2. The length of the flowpath to width ratio needs to be at least 3:1 in make sure the stormwater is not short circuited through the basin. The second forebay looks to not be providing the 3:1 flowpath. Please make sure both forebays are providing the 3:1 flowpath. 3. A few inconsistencies were noted on the plansheets. The outlet detail on CG500 does not match the details on CG504. Also, the details on CG504 should match. One is missing the orifice and the trash guards are different. Please revise the details to be accurate. 4. Please show proposed drainage easements and public right of way on the plans. The requested information should be received by this Office prior to August 17, 2012, or the application will be returned as incomplete. The return of a project will necessitate resubmittal of alt required items, including the application fee. If you need additional time to submit the information, please send your request, including date by which you expect to submit the required information, to my attention. The Division is allowed 90 days from the receipt of a completed application to issue the permit. Please reference the State assigned project number on all correspondence. New original documents must be provided and copies are not acceptable. If you have any questions concerning this matter feel free to contact me at (919) 807.6368 or brian.lowther@ncdenr. ov. Sincerely, Brian Lowther Environmental Engineer cc: 'Fayetteville Regional Office Stormwater Permitting Unit Files ec: David Heins, Environmental Division Chief (DPW) Wetlands and Stormwater Branch 1�TOne 1617 Mail Service Center, Raleigh, North Carolina 27699-1617 1 V O hCarolina Location: 512 N. Salisbury St. Raleigh, North Carolina 27604atura!!u Phone: 919M7-63001 FAX: 91H07-6494 Internet: www.ncwatealuality.org DWQ USE ONLY Date Received Fee Paid Permit Number .50,5 * 1 -I I l U 9 3 �) I 5w t-P I a- D I (J Lp Applicable Rules: ❑ Coastal SW -1995 ❑ Coastal SW - 2008 ❑ Ph II - Post Construction (select all that apply) ❑ Non -Coastal SW- HQW/ORW Waters ❑ Universal Stormwater Management Plan ❑ Other WQ M mt Plan: State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM This form may be photocopied for use as an original I. GENERAL INFORMATION 1. Project Name (subdivision, facility, or establishment name - should be consistent with project name on plans, specifications, letters, operation and maintenance agreements, etc.): SOF Training Facility (Pope) 2. Location of Project (street address): Booster Street City:Ft Bragg County: Cumberland Zip:28310 3. Directions to project (from nearest major intersection): 4. Latitude:35° 30' 44" N Longitude:79° 01' 81" W of the main entrance to the project. H. PERMIT INFORMATION: 1. a. Specify whether project is (check one): ®New ❑Modification b.If this application is being submitted as the result of a modification to an existing permit, list the existing permit number , its issue date (if known) , and the status of construction: ❑Not Started ❑Partially Completed* ❑ Completed* *provide a designer's certification Specify the type of project (check one): ❑Low Density ®High Density ❑Drains to an Offsite Stormwater System ❑Other If this application is being submitted as the result of a previously returned application or a letter from DWQ requesting a state stormwater management permit application, list the stormwater project number, if assigned, and the previous name of the project, if different than currently proposed, 4. a. 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): ❑LAMA Major ❑NPDES Industrial Stormwater ®Sedimentation/Erosion Control: 4.0 ac of Disturbed Area ❑404/401 Permit: Proposed Impacts b.If any of these permits have already been acquired please provide the Project Name, Project/Permit Number, issue date and the type of each permit:FB-SOF Training Facility (Pope)/CUMBE-2012-167/Sediment and JUL 2.7 2012 Form SWU-101 Version 07]un2010 Page 1 of III. CONTACT INFORMATION 1. a. Print Applicant / Signing Official's name and title (specifically the developer, property owner, lessee, designated government official, individual, etc. who owns the project}: Applicant/Organization: Directorate of Public Works (DPW) Signing Official & Title:Mr. David Heins, Environmental Division Cheif (DPW) b.Contact information for person listed in item 1a above: Street Address:2175 Reilly Road Stop A City:Fort Bragg State:NC Zip:28310-5000 Mailing Address (if applicable):2175 Reilly Road Stop A City:Fort Bragg State: NC Zip:28310-5000 Phone: (910 } 396-8207 Fax: ( 910 } 907-2420 Email:david.a.heins.civ@mail.mil c. Please check the appropriate box. The applicant listed above is: ® The property owner (Skip to Contact Information, item 3a) ❑ Lessee* (Attach a copy of the lease agreement and complete Contact Information, item 2a and 2b below) ❑ Purchaser* (Attach a copy of the pending sales agreement and complete Contact Information, item 2a and 2b below) ❑ Developer* (Complete Contact Information, item 2a and 2b below.) 2. a. Print Property Owner's name and title below, if you are the Iessee, purchaser or developer. (This is the person who owns the property that the project is located on): Property Owner/Organization: Signing Official & Title: b.Contact information for person listed in item 2a above: Street Address: City: State: Zip: Mailing Address (if applicable): City: State: Zip: Phone: ( ) Fax: Email: a. (Optional) Print the name and title of another contact such as the project's construction supervisor or other person who can answer questions about the project: Other Contact Person/Organization: Mr. Lee Ward Signing Official & Title:DPW/Water Management Branch b.Contact information for person listed in item 3a above: Mailing Address:Bldg 0-9125, McKellars Road City:Fort Bragg Phone: (910 ) 396-2301 Email: lee.p.ward.civ®mail.mil 4. Local jurisdiction for building permits: Point of Contact: State:NC Zip:28310 Fax: ( 910 ) 907-2420 Phone #: ( } Form SWU-101 Version 07Jun2010 Page 2 of 6 IV. PROJECT INFORMATION 1. In the space provided below, briefly summarize how the stormwater runoff will be treated. Wet Detention Pond 2. a. If claiming vested rights, identify the supporting documents provided and the date they were approved: ❑ Approval of a Site Specific Development Plan or PUD Approval Date: ❑ Valid Building Permit Issued Date: ❑ Other: Date: b.If claiming vested rights, identify the regulation(s) the project has been designed in accordance with: ❑ Coastal SW - 1995 ❑ Ph II - Post Construction 3. Stormwater runoff from this project drains to the Cape Fear _ River basin. 4. Total Property Area: 4.0 acres 5. Total Coastal Wetlands Area: acres 6. Total Surface Water Area: acres 7. Total Property Area (4) - Total Coastal Wetlands Area (5) - Total Surface Water Area (6) = Total Project Area,: 4.0 acres + Total project area shall be calculated to exclude the following the normal pool of impounded structures, the area between the batiks of streams and rivers, the area below the Nonnal High Water (NMI\} line or Mean High Water (MHW) line, and coastal wetlands landward from the NHW (or MHW) line. The resultant project area is used to calculate overall percent built upon area (B UA). Non -coastal wetlands landward of the NHW (or MHW) line may be included in the total project area. 8. Project percent of impervious area: (Total Impervious Area / Total Project Area) X 100 = 36.5 % 9. How many drainage areas does the project have?1 (For high density, count 1 for each proposed engineered stormwater BMP. For low density and other projects, use 1 for the whole property area) 10. Complete the following information for each drainage area identified in Project Information item 9. If there are more than four drainage areas in the project, attach an additional sheet with the information for each area provided in the same format as below. Basin Information Drainage Area 1 Drainage Area Drainage Area Drainage Area Receiving Stream Name Little River (Lower Little River Stream Class C Stream Index Number * 18-23-(24) Total Drainage Area (sf) 234681 On -site Drainage Area (so 174250 Off -site Drainage Area (so 60431 Proposed Impervious Area** (so 85748 % Impervious Area** total 36.5 Impervious- Surface Area Drainage Area 1 Drainage Area Drainage Area _ Drainage Area _ On -site Buildings/Lots (so 14252 On -site Streets (SO 0 1 On -site Parking (so 30042 On -site Sidewalks (so 3657 ? f �5�� Other on -site (so 625 Future (so 0 ] Off -site (so 15973 f Existing BUA*** (so 0 1 Total (so: 85748 Stream Class and Index Number can be determined at: N07.//portAl.ticde)ir.org leb/wq[ps/csu/classificatirnts Form SWU-101 Version 07Jun2010 Page 3 of ** Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas, sidewalks, gravel areas, etc. *** Report only that amount of existing BUA that will remain after development. Do not report any existing BUA that is to be removed and which will be replaced by new BUA. 11. How was the off -site impervious area listed above determined? Provide documentation. Area measurement using Microstation survey file. Projects in Union County: Contact DtyQ Central Office staff to check if the project is located within a Threatened & Endangered Species watershed that maybe subject to more stringent stormwater requirements as per NCAC 02B . 0600. V. SUPPLEMENT AND O&M FORMS The applicable state stormwater management permit supplement and operation and maintenance (O&M) forms must be submitted for each BMP specified for this project. The latest versions of the forms can be downloaded from http://portal.ncdenr.org/web/wq/ws/su/bmp-manual. 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. A detailed application instruction sheet and BMP checklists are available from hn://portal.ncdenr,org/web/wq/ws/su/statesw/forms dots. The complete application package should be submitted to the appropriate DWQ Office. (The appropriate office may be found by locating project on the interactive online map at http://12ortal.ncdenr.org/web/wq/ws/su/mans.) Please indicate that the following required information have been provided by initialing in the space provided for each item. All original documents MUST be signed and initialed in blue ink. Download the Iatest versions for each submitted application package from hqp://portal.ncdenr.org/web/wq/ws/su/statesw/forms dots. 1. Original and one copy of the Stormw-ater Management Permit Application Form. ln' ' 2. Original and one copy of the signed and notarized Deed Restrictions & Protective Covenants �M Form, (if required as per Part VII below) , 3. Original of the applicable Supplement Form(s) (sealed, signed and dated) and O&M �- agreement(s) for each BMP. 4. Permit application processing fee of $505 payable to NCDENR. (For an Express review, refer to h!W://www.envhelp.org/pages/onestopexpress.htmi for information on the Express program and the associated fees. Contact the appropriate regional office Express Permit Coordinator for additional information and to schedule the required application meeting.) 5. A detailed narrative (one to two pages) describing the stormwater treatment/management for 6. A USGS map identifying the site location. If the receiving stream is reported as class SA or the `— receiving stream drains to class SA waters within 1/2 mile of the site boundary, include the 1/2 mile radius on the map. 7. Sealed, signed and dated calculations, 8. Two sets of plans folded to 8.5" x 14" (sealed, signed, & dated), including: a. Development/ Project name. b. Engineer and firm. c. Location map with named streets and NCSR numbers. d. Legend. e. North arrow. f. Scale. g. Revision number and dates. h. Identify all surface waters on the plans by delineating the normal pool elevation of impounded structures, the banks of streams and rivers, the MHW or NHW Iine of tidal waters, and any coastal wetlands landward of the MHW or NHW Iines. • Delineate the vegetated buffer landward from the normal pool elevation of impounded structures, the banks of streams or rivers, and the MHW (or NHW) of tidal waters. i. Dimensioned property/project boundary with bearings & distances. j. Site Layout with all BUA identified and dimensioned. k. Existing contours, proposed contours, spot elevations, finished floor elevations. 1. Details of roads, drainage features, collection systems, and stormwater control measures. m. Wetlands delineated, or a note on the plans that none exist. (Must be delineated by a qualified person. Provide documentation of qualifications and identify the person who made the determination on the plans. n. Existing drainage (including off -site), drainage easements, pipe sizes, runoff calculations. Form SWU-101 Version 07Jun2010 Page 4 of 6 o. Drainage areas delineated (included in the main set of plans, not as a separate document). p. Vegetated buffers (where required). 9. Copy of any applicable soils report with the associated SHWT elevations (Please identify 10 11 elevations in addition to depths) as well as a map of the boring locations with the existing elevations and boring logs. Include an 8.5"xll" copy of the NRCS County Soils map with the project area clearly delineated. For projects with infiltration BMPs, the report should also include the soil type, expected infiltration rate, and the method of determining the infiltration rate. (Infiltration Devices submitted to WiRO: Schedule a site visit for DWQ to verify the SHVVT prior to submittal, (910) 796-7378.) N� A copy of the most current property deed. Deed book: Page No: For corporations and limited liability corporations (LLC): Provide documentation from the NC Secretary of State or other official documentation, which supports the titles and positions held by the persons listed in Contact Information, item la, 2a, and/or 3a per NCAC 2H.1003(e). The corporation or LLC must be listed as an active corporation in good standing with the NC Secretary of State, otherwise the application will be returned. hn://www.secretary.state.nc.us/Corporations/CSearch.aspx VII. DEED RESTRICTIONS AND PROTECTIVE COVENANTS For all subdivisions, outparcels, and future development, the appropriate property restrictions and protective covenants are required to be recorded prior to the sale of any lot. If lot sizes vary significantly or the proposed BUA allocations vary, a table listing each lot number, lot size, and the allowable built -upon area must be provided as an attachment to the completed and notarized deed restriction form. The appropriate deed restrictions and protective covenants forms can be downloaded from hm://portal,ncdenr.org/web/wq/ws/su/statesw/forms does. Download the latest versions for each submittal. In the instances where the applicant is different than the property owner, it is the responsibility of the property owner to sign the deed restrictions and protective covenants form while the applicant is responsible for ensuring that the deed restrictions are recorded. By the notarized signature(s) below, the permit holder(s) certify that the recorded property restrictions and protective covenants for this project, if required, shall include all the items required in the permit and listed on the forms available on the website, 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 lot. VIII. CONSULTANT INFORMATION AND AUTHORIZATION Applicant: Complete this section if you wish to designate authority to another individual and/or firm (such as a consulting engineer and/or firm) so that they may provide information on your behalf for this project (such as addressing requests for additional information). Consulting Engineer:Don Higgins Consulting Firm: Day & Zimmermann Mailing Address:125 The Parkway, Suite 400 City:Greenville State:SC Zip:29615 Phone: (864 ) 242-6788 Fax: (864 _ } 241-6750 Email:don.higgins@dayzim.com IX. PROPERTY OWNER AUTHORIZATION (if Contact Information, item 2 has been filled out, complete this section) I, (print or type name of person listed in Contact Information, item 2a) , certify that I own the property identified in this permit application, and thus give permission to (print or type name of person listed in Contact Information, item 2a) with (print or type name of organization listed in Contact Information, item 1a) to develop the project as currently proposed. A copy of the lease agreement or pending property sales contract has been provided with the submittal, which indicates the party responsible for the operation and maintenance of the stormwater system. Form SWU-101 Version 07Jun2010 Page 5 of 6 . ,, . , As the legal property owner I acknowledge, understand, and agree by my signature below, that if my designated agent (entity listed in Contact Information, item 1) dissolves their company and/or cancels or defaults on their lease agreement, or pending sale, responsibility for compliance with the DWQ Stormwater permit reverts back to me, the property owner. As the property owner, it is my responsibility to notify DWQ immediately and submit a completed Name/Ownership Change Form within 30 days; otherwise I will be operating a stormwater treatment facility without a valid permit. I understand that the operation of a stormwater treatment facility without a valid permit is a violation of NC General Statue 143-215.1 and may result in appropriate enforcement action including the assessment of civil penalties of up to $25,000 per day, pursuant to NCGS-143-215.6. Signature: Date: I, a Notary Public for the State of County of do hereby certify that personally appeared before me this _ day of , and acknowledge the due execution of the application for a stormwater permit. Witness my hand and official sea[, SE,AI_ My commission expires X. APPLICANT'S CERTIFICATION I, (print or type narrre of person listed in Contact lrrfornration, item In) Mr. David Heins , 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, and that the proposed project complies with the requirements of the applicable stormwater 1 s un r 15A NCAC 21-1 .1000, SL. 2006-246 (Ph. II - Post Construction) or SL, 2008-21-1. Signature: Date: ( 2 Z I, , a Notary Public for the State of do hereby certify that County of personally appeared before me this _ clay of , and acknowledge the due execution of the application for a stormwater permit. Witness my hand and official seal, SEAL My commission expires Form SWU-101 Version 07Jun2010 Page 6 of 6 Permit Number: (to he pros ided by DIVA) Drainage Area Number: Wet Detention Basin Operation and Maintenance Agreement 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. 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): ❑ does ® does not incorporate a vegetated filter at the outlet. This system (check one): ® does ❑ does not incorporate pretreatment other than a forebay. Important maintenance procedures: - Immediately after the wet detention basin is established, the plants on the vegetated shelf and perimeter of the basin should be watered twice weekly if needed, until the plants become established (commonly six weeks). - No portion of the wet detention pond should be fertilized after the first initial fertilization that is required to establish the plants on the vegetated shelf. - Stable groundcover should be maintained in the drainage area to reduce the sediment load to the wet detention basin. - If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment through the emergency drain should be minimized to the maximum extent practical. - Once a year, a dam safety expert should inspect the embankment. After the wet detention pond is established, it should be inspected once a month 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 should be kept in a known set location and must be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: I -low I will remediate theproblem: The entire BMP Trash/debris is present. Remove the trash/debris. The perimeter of the wet Areas of bare soil and/or Regrade the soil if necessary to detention 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. Vegetation is too short or too Maintain vegetation at a height of long. approximately six inches. Forrn SW401-Wet Detention Basin O&M-Rev.4 Page I of 4 Permit Number: (to he provided by DWQ) Drainage Area Number: BMP element: Potentialproblem: Flow l will remediate theproblem: The inlet device: pipe or The pipe is clogged. Unclog the pipe. Dispose of the Swale sediment off -site. The pipe is cracked or Replace the pipe. otherwise damaged. Erosion is occurring in the Regrade the Swale if necessary to Swale. smooth it over and provide erosion control devices such as reinforced turf matting or riprap to avoid future problems with erosion. The forebay Sediment has accumulated to Search for the source of the a depth greater than the sediment and remedy the problem if original design depth for possible. Remove the sediment and sediment storage. dispose of it in a location where it will not cause impacts to streams or the 13MP. Erosion has occurred. Provide additional erosion 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 pesticide is used, wipe it on the plants rather than spraying. The vegetated shelf Best professional practices Prune according to best professional show that pruning is needed practices to maintain optimal plant health. Plants are dead, diseased or Determine the source of the dying. problem: soils, hydrology, disease, etc. Remedy the problem and replace plants. Provide a one-time fertilizer application to establish the ground cover if a soil test indicates it is necessary. Weeds are present. Remove the weeds, preferably by hand. If pesticide is used, wipe it on the plants rather than spraying. The main treatment area Sediment has accumulated to Search for the source of the a depth greater than the sediment and remedy the problem if original design sediment possible. Remove the sediment and storage depth. dispose of it in a location where it will not cause impacts to streams or the BMP. Algal growth covers over Consult a professional to remove 50% of the area. and control the algal growth. Cattails, phragmites or other Remove the plants by wiping them invasive plants cover 50% of with pesticide (do not spray). the basin surface. Form SW401-Wet Detention Basin O&M-Rev.4 Page 2 of 4 Pennit Number: (to he pro►,ided by DJVQ) Drainage Area Number: BMP element: Potentialproblem: blow I will remediate theproblem: The embankment Shrubs have started to grow Remove shrubs immediately. on the embankment. Evidence of muskrat or Use traps to remove muskrats and beaver activity is present. consult a professional to remove beavers. A tree has started to grow on Consult a dam safety specialist to the embankment. remove the tree. An annual inspection by an Make all needed repairs. appropriate professional shows that the embankment needs repair. if applicable) 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 local NC Division of damage have occurred at the Water Quality Regional Office, or outlet. the 401 Oversight Unit at 919-733- 1 78b. 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 _172.30 . feet in the main pond, the sediment shall be removed. When the permanent pool depth reads 172.30 feet in the forebay, the sediment shall be removed. Sediment Removal Bottom 172.30 --------------- FOIZEBAY BASIN DIAGRAM (fill in the blank:) IVolume -ft Min. Sediment Storage Permanent Pool Llevation 175.90 Pool Sediment Removal Elevation 172.30 Volume Bottom 131evation 171.30 MAIN POND pediment Storage Form SW401-Wet Detention Basin O&M-Rev.4 Page 3 of 4 Pennit Number: (to be provided by DI'Q) I acknowledge and agree by my signature below that I atn 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 nanie:SOF Training hey (Pope)_ BMP drainage area nwnber:Drainage Area Print name: Mr. David Heins Title: Directorate of Public Works (DPW) /Chief -Environmental Division Address:2175 Reilly Road Stop A, Fort Brag_t„ NC 28310-5000 Phone: (910) 396-2301,, , / Signature: Date: 2-��il l C 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 (lie subdivision has been named the president. I, , a Notary Public for the State of County of , do hereby certify that personally appeared before me this day of , , and acknowledge the due execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal, SEAL My commission expires. Dorm SW401-We( Detention Basin O&M-Rev.4 Page 4 of 4 Permit No (to be provider! by D WQ) A�� �pF w a TF4 p o NCDENR a Y STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM WET DETENTION BASIN SUPPLEMENT This form must be filled out, printed and submitted. The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information. L :PROJECT INFORMATION..:%,. , : .=,.3i''_% Project name SOF Training Facifity, Pope Field!Cumberiand County, NC Contact person Don Higgins Phone number B64.241.6768 Date 14-Jun-12 Drainage area number DA 1 A. DESIGN INFORMATION - Site Characteristics Drainage area 234,681 fe Impervious area, post -development 85,748 fC % impervious 36.54 % Design rainfall depth 1.0 in Storage Volume: Non-SAWaters Minimum volume required Volume provided Storage Volume: SA Waters 1.5' runoff volume Pre -development 1-yr. 24-hr runoff Post -development 1-yr, 24-hr runoff Minimum volume required Volume provided Peak Flow Calculations is the prelpost control of the Iyr 24hr storm peak flow required? 1-yr, 24-hr rainfall depth Rational C, pre -development Rational C, post -development Rainfall intensity: 1-yr, 24-hr storm Pre -development l-yr, 24-hr peak flow Post -development 1-yr, 24-hr peak flow Pre/Post 1-yr. 24-hr peak flow control Elevations Temporary pool elevation Permanent pool elevation SHWT elevation (approx. at the perm. pool elevation) Top of 1 Oft vegetated shelf elevation Bottom of 1 OR vegetated shelf elevation Sediment cleanout, top elevation (bottom of pond) Sediment cleanout, bottom elevation Sediment storage provided Is there additional volume stored above the state -required temp. pool? Elevation of the top of the additional volume 7,495 OK 7.500 R' OK, volume provided is equal to or in excess of volume required. ft3 (Y or N) 3.7 in 0.36 (unitless) 0.37 (unitless) 4.17 inlhr OK 4.41 ft3(sec 8.35 ft3lsec 3.94 ft3lsec 176.40 fmsl 175.90 fmsl 174.10 fmsl 176.40 fmsl 175.40 fmsl 172.30 fmsl 171.30 fmsl 1.00 ft (Y or N) 176.4 fmsl OK Form 5W401-Wet Detention Basin-Rev.8-9117M Parts I. & II. Design Summary. Pape 1 of 7 Permit (to be provided by DWQ) !l: DESIGN INFORMATION Surface Areas Area, temporary pool 11,800 ft, Area REQUIRED, permanent pool 5,867 ft' SAIDA ratio 2,50 (unitless) Area PROVIDED, permanent pool, A,,,m pdd, 11,000 OK Area, bottom of 1 Oft vegetated shelf. Add, ma 8,375 � Area, sediment cleanout, top elevation (bottom of pond), Add,-pd,d 3,850 Volumes Volume, temporary pool 7,500 ft' OK Volume, permanent pool. V.,-,W 25,225 ft' Volume, forebay (sum of forebays if mare than one forebay) 5,500 ft3 Forebay % of permanent pool volume 218% % OK SAIDA Table Data Design TSS removal 90 % Coastal SAIDA Table Used? N (Y or N) Mountain/Piedmont SAIDA Table Used? Y (Y or N) SAIDA ratio 2.50 (unitless) Average depth (used in SAIDA table): Calculation option 1 used? (See Figure 10-2b) N (Y or N) Volume, permanent pool, Vperm-PW 25,225 ft3 Area provided, permanent pool, A,, d ,dd, 11,000 ft Average depth calculated 3.00 It OK Average depth used in SAIDA, d,,, (Round to nearest 0.5ft) 3.0 ft OK Calculation option 2 used? (See Figure 10-2b) Y (Y or N) Area provided, permanent pool, A,,,m_dd, 11,000 ft.2 Area, bottom of 1Oft vegetated shelf, Aid, men 8,375 f' Area, sediment cleanout, top elevation (bottom of pond), Am_,d d 3,850 17 "Depth" (distance blue bottom of 1 Oft shelf and top of sediment) 3 10 ft Average depth calculated 3.00 ft OK Average depth used in SAIDA, d. (Round to nearest 0 5ft) 3.0 ft OK Drawdown Calculations Drawdown through orifice? Y (Y or N) Diameter of onfice (if circular) 1.50 in Area of orifice (if -non -circular) in Coefficient of discharge (Co) 0.60 (unitless) Driving head (Hd) 0.60 ft Drawdown through weir N (Y or N) Weir type {unitless) Coefficient of discharge (C.) (unitless) Length of weir (L) ft Driving head (H) ft Pre -development 1-yr, 24-hr peak flow 4.41 ft3lsec Post -development 1-yr, 24-hr peak flow 8.35 ft31sec Storage volume discharge rate (through discharge orifice orwelr) 0.04 ft'Isec Storage volume drawdown time 3.28 days OK, draws down in 2-5 days. Additional Information Vegetated side slopes 3 :1 OK Vegetated shelf slope 10 :1 OK Vegetated shelf width 10.0 ft OK Length of flowpath to width ratio 3 :1 CK Length to width ratio 1.5 :1 OK Trash rack for overflow & orifice? Y (Y or N) OK Freeboard provided 1 0 ft OK Vegetated filter provided? N (Y or N) OK Recorded drainage easement provided? N (Y or N) Insufficient. Recorded drainage easement required. Capures all runoff at ultimate build -out? Y (Y or N) OK Drain mechanism for maintenance or emergencies is: Emergency Spillway Form SW4D1-Wet Detention Basin-Rev.S-9117109 Parts I. B It. Design Summary, Pago 2 of 7 Permit No. (to be provided by DWQ) JUL 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 Init-ia1� Sheet No. 1. Plans (1" - 50' or larger) of the entire site showing: CG110 Design at ultimate build -out, C13110 Off -site drainage (if applicable), CG110 Delineated drainage basins (include Rational C coefficient per basin), CG110/504 Basin dimensions, C13110 Pretreatment system, CG504 High flow bypass system, CG110 Maintenance access, NIA Proposed drainage easement and public right of way (ROW), CG504 Overflow device, and NIA Boundaries of drainage easement. 2. Partial plan (V = 30' or larger) and details for the wet detention basin showing: CG504 Outlet structure with trash rack or similar, CG110 Maintenance access, CG110/504 Permanent pool dimensions, CG504 Forebay and main pond with hardened emergency spillway, CG504 Basin cross-section, CG505 Vegetation specification for planting shelf, and CG504 Filter strip, 3. Section view of the wet detention basin (1" = 20' or larger) showing: CG110/504 Side slopes, 3:1 or lower, CG110 Pretreatment and treatment areas, and CG1101500 Inlet and outlet structures. 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified CE506 on the plans prior to use as a wet detention basin. 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay, CG503 to verify volume provided. 7� 6, A construction sequence that shows how the wet detention basin will be protected from sediment until the CE101-103 entire drainage area is stabilized. Report 7. The supporting calculations. 8. A copy of the signed and notarized operation and maintenance (O&M) agreement. 9. A copy of the deed restrictions (if required). NIA 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County Appendix soil maps are not an acceptable source of soils information. Form SW401-Wet Detention Basin-Rev.8-91171D9 Part III. Required Items Checklist, Page 3 of 7 Average Depth Calculation Figure 10-2b, Option 2 Surface Area at Permanent Pool (Main Pond) 7725 ft2 Surface Area at Bottom of Shelf (Main Pond) 6025 ft2 Surface Area at Permanent Pool (Forebay 1) 2075 ft2 Surface Area at Bottom of Shelf (Forebay 1) 1500 ft2 Surface Area at Permanent Pool (Forebay 2) 1360 ft2 Surface Area at Bottom of Shelf (Forebay 2) 850 ft2 Total Surface Area at Permanent Pool 11000 ft2 Total Surface Area at Bottom of Shelf 8300 ft2 Surface Area at Bottom of Pond 3850 ft2 Depth 3.5 ft Average Depth 3.00 ft Temporary Pool Volume per Section 3.3.1 of NCDENR Stormwater Manual IA 0.37 Rv 0.38 Rv=0.05+0.9" IA A 5.39 ac RD 1.00 in V=3630"RD*Rv"A Volume 7494 cf Temporary Pool Depth 0.68 ft Orifice Equation 3.5.2 Diamter Outlet Pipe (in) 1.5 CD 0.6 Area of flow at entrance (sf) 0.012 g 32.2 Ho Driving Head (13) (ft) 0.20 Q=CD"A"SQRT(2*g"Ho) Calculated Q (cfs) 0.026 Temporary Pool (cf) 7500 Drawdown Time (hours) 78.84 Drawdown Time (days) 3.28 L Stage -Storage Table Elevation (ft) Stage (ft) Storage (ft3)" Cumulative Storage (ft3) 172.30 0 0 0 173.00 0.7 2835 2835 173.50 1,21 2875 5710 174.00 1.7 2970 8680 174.50 2.2 3110 11790 175.00 2.7 3300 15090 175.50 3.2 4435 19525 175,901 3.6 57001 25225 176,401 4.11 75001 32725 "Storage area measured in Microstation