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HomeMy WebLinkAboutSW8091204_Historical File_20091229Aiv,-4irA NCDENR North Carolina Department of Environment and Natural Resources Division of Water Quality Beverly Eaves Perdue Coleen H. Sullins Governor December 29, 2009 Marty K. Lawing, County Manager Brunswick County 45 Courthouse Drive NE, Building E Bolivia, NC 28422 Director Subject: Permit No. SW8 091204 Northwest Water Treatment Plant Improvements Low Density Stormwater Project Brunswick County Dear Mr. Lawing: Dee Freeman Secretary The Wilmington Regional Office received a Stormwater Management Permit Application for Northwest Water Treatment Plan Improvements on December 28, 2009. Staff review of the plans and specifications has determined that the project, as proposed, will comply with the Stormwater Regulations set forth in Session Law 2008-211 and Title 15A NCAC 2H.1000. We are forwarding Permit No. SW8 091204 dated December 29, 2009, for the construction of the subject project. This permit shall be effective from the date of issuance until rescinded and shall be subject to the conditions and limitations as specified therein, and does not supercede any other agency permit that may be required. If any parts, requirements, or limitations contained in this permit are unacceptable, you have the right to request an adjudicatory hearing upon written request within thirty (30) days following receipt of this permit. This request must be in the form of a written petition, conforming to Chapter 150B of the North Carolina General Statutes, and filed with the Office of Administrative Hearings, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such demands are made this permit shall be final and binding. If you have any questions please contact either M.J. Naugle or me at (910) 796-7215. Si erel6y, Georgette rcott Stormwater Supervisor Division of Water Quality GDS/mjn: S:\WQS\STORMWATER\PERMIT\091204 dec09 cc: Matthew Jones, Hazen and Sawyer, 919-833-7152, fax: 919-833-1828 Brunswick County Inspections Jeff Phillips, Brunswick County Engineering Wilmington Regional Office Central Files M.J. Naugle Wilmington Regional Office 127 Cardinal Drive Extension, Wilmington, North Carolina 28405 1�TOne Phone: 910-796-7215 \ FAX: 910-350-2004 \ Customer Service:1-877-623-6748 lv O Carolina Internet: www.ncwaterquality.org Naturally An Equal Opportunily \ Aiflrmative Action Employer State Stormwater Management Systems Permit No. SW8 091204 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STAVE STORMWATER MANAGEMENT PERMIT LOW 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 Marty K. Lawing, County Manager and Brunswick County Northwest Water Treatment Plant Improvements 4091 Butler Road, Leland, Brunswick County FOR THE construction, operation and maintenance of a 24% low density development in compliance with the provisions of Session Law 2008-211 and Title 15A NCAC 2H .1000 (hereafter referred to singly and collectively 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. The Permit shall be effective from the date of issuance until rescinded and shall be subject to the following specific conditions and limitations: I. DESIGN STANDARDS 1. This permit covers the construction of a total of 55,820 square feet of proposed built - upon area. There is 147,126 square feet of existing impervious area built prior to 1988. The total amount of impervious area with this permit ice, v5 square feet. �.P5 f smc pe 3 A 4o4 4: kc- q � 2. The overall tract built -upon area percentage for the project must be maintained at no more than 24%, as required by Section .1005 of the stormwater rules. 3. Approved plans, application, supplements and specifications for projects covered by this permit are incorporated by reference and are enforceable parts of the permit. 4. The only runoff conveyance systems allowed will be vegetated conveyances such as swales with minimum side slopes of 3:1 (H:V) as defined in the stormwater rules and approved by the Division. 5. Where the flow rate in a swale exceeds 2 fps, a mechanism to prevent erosion shall be provided at the end of the swale, prior to discharging into the 50 foot buffer, surface waters or wetlands. 6. No piping is allowed except that minimum amount necessary to direct runoff beneath an impervious surface such as a road or to provide access. 7. Projects covered by this permit will maintain a minimum 50-foot-wide vegetative buffer adjacent surface waters. The width of the buffer is measured horizontally from the normal pool of impounded structures, from the bank of each side of streams or rivers, and from the mean high water line of tidal waters, perpendicular to the shoreline. Page 2 of 5 State Stormwater Management Systems Permit No. SW8 091204 8. All runoff directed into and through the vegetative buffer must flow through the buffer in a diffuse manner. 9. All runoff directed into wetlands shall flow into and through the wetlands at a non -erosive velocity. 10. Roof drains must terminate at least 50 foot from surface waters. II. SCHEDULE OF COMPLIANCE The permittee shall not allow any person, including the permittee, to alter any part of the approved stormwater management system or fill in, alter, or pipe any drainage feature (such as swales) as shown on the approved plans, except for minimum driveway crossings, unless and until the permittee shall have submitted a modification to the permit and received approval from the Division of Water Quality. 2. The permittee is responsible for verifying that the proposed built -upon area does not exceed the allowable built -upon area. 3. 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. 4. 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 the approved plans, regardless of size. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area. e. Further subdivision, acquisition, or sale of the project area, in whole or in part. 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 any vegetative conveyance shown on the approved plan, except for minimum driveway crossings. 5. Swales and other vegetated conveyances shall be constructed in their entirety, vegetated, and operational for their intended use prior to the construction of any built - upon surface. 6. During construction, erosion shall be kept to a minimum and any eroded areas of the swales or other vegetated conveyances will be repaired immediately. 7. The permittee shall at all times provide the operation and maintenance necessary to operate the permitted stormwater management systems at optimum efficiency to include: a. Inspections b Sediment removal. C. Mowing, and re -vegetating of the side slopes. d. Immediate repair of eroded areas. e. Maintenance of side slopes in accordance with approved plans and specifications. Page.3 of 5 State Stormwater Management Systems Permit No. SW8 091204 8. Prior to the sale or subdivision of this project, in whole or in part, the permittee is required to submit a permit modification. 9. Construction of additional built -upon area in excess of 202,955 square feet will require 'a permit modification. Construction of additional impervious areas such that low density requirements are no longer met must be submitted to DWQ and a permit modification must be issued prior to construction. An engineered system will be required to collect and treat the runoff from all. built -upon area associated with the project, including that area permitted under the low density option. 10. Within 30 days of completion of the project, the permittee shall certify in writing that the project has been constructed in accordance with the approved plans. 11. The permittee shall submit all information requested by the Director or his/her representative within the time frame specified in the written information request. III. GENERAL CONDITIONS 1. Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to an enforcement action by the Division of Water Quality, in accordance with North Carolina General Statutes 143-215.6A to 143-215.6C. 2. The permit issued shall continue in force and effect until revoked or terminated. 3. 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. 4. 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 Title 15A of the North Carolina Administrative Code, Subchapter 2H.1000; and North Carolina General Statute 143-215.1 et. al. 5. Unless specified elsewhere, permanent seeding requirements for the swales must follow the guidelines established in the latest version of the North Carolina Erosion and Sediment Control Planning and Design Manual. 6. This permit is not transferable to any person or entity except after notice to and approval by the Director. The Director may require modification or revocation and re -issuance of the permit to change the name and incorporate such other requirements as may be necessary. In the event of a name or ownership change, a completed Name/Ownership Change form must be submitted to the Division of Water Quality, signed by the parties involved, and accompanied by appropriate documentation as listed on page 2 of the form. The approval of this request will be considered on its merits, and jnay or may not be approved. 7. The permittee is responsible for compliance with all permit conditions until the Director approves the permit transfer. Neither the sale of the project, in whole or in part, nor the transfer of common area to a third party, shall be considered an approved permit transfer request. 8. The permittee grants permission to DENR Staff to enter the property for the purpose of inspecting all components of the stormwater management facility. 9. The permittee shall notify the Division in writing of any name, ownership or mailing address changes at least 30 days prior to making such changes. Page 4 of 5 State Stormwater Management Systems, Permit No. SW8 091204 10. The issuance of this permit does not preclude the Permittee from complying with and obtaining any and all permits or approvals 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 prior to receipt of the necessary permits or approvals to do so is considered a violation of NCGS 143-215.1, and subject to enforcement procedures pursuant to NCGS 143-215.6. Permit issued this the twenty-ninth day of December 2009. /NORCAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION ------------ s --------------- for Coleen H. ullinS. Director Division of Water Quality By Authority of the Environmental Management Commission Permit Number SW8 091204 Page 5 of 5 DWQ USE ONLY Date Received Fee Paid Permit Number - -D 17 1o0 . '-9'1- G 3G 28 I -5A7 O� o / o Applicable Rules: ❑ Coastal SW -1995 Coastal SW - 2008 ❑ Ph 11- Post Construc 'on (select all that apply) ❑ Non -Coastal SW- HQW/ORW Waters ❑ Universal Stormwater Management Plan ❑ Other WQ Mgmt Plan: State of North Carolina Department of Environment and Natural ResuumesaaJMW Division of Water Quality � 2009 STORMWATER MANAGEMENT PERMIT APPLICATION FORM This form may be photocopied for use as an original �- BY�— 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.): Northwest Water Treatment Plant Imvrovements 2. Location of Project (street address): 4091 Butler Road City:Leland County:Brunswick Zip:28451 3. Directions to project (from nearest major intersection): From Wilming on, go West on US-74. Exit onto State Road 1426, headed North. Turn left onto State Road 1460. 4. Latitude:340 18' 11.21" N Longitude:78° 6' 21.29" W of the main entrance to the project. II. 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 2. Specify the type of project (check one): ®Low Density []High Density ❑Drains to an Offsite Stormwater System []Other 3. 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: 5 ac of Disturbed Area 0404/401 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: Form SWU-101 Version 07July2009 Page 1 of 6 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:Brunswick County Signing Official & Titie:Marty K. Lawing County Manager b. Contact information for person listed in item 1a above: Street Address:Building E, 45 Courthouse Drive NE City:Bolivia State:NC Zip:28422 Mailing Address (if applicable):Post Office Box 249 City:Bolivia State:NC Zip:28422 Phone: 910 ) 253-2000 Fax: (910 ) 253-2022 Email:admin®brunsco.net 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 lessee, purchaser or developer. (This is the person who owns the property that the project is located on): Property Owner/Organization: Signing Official & 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: 3. 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: Signing Official & Title: b. Contact information for person listed in item 3a above: Mailing Address: City: State: Zip: Phone: ( ) Fax: ( ) Email: 4. Local jurisdiction for building permits: Brunswick County Point of Contact:Brunswick County Planning Office Phone #: (910 ) 253-2025 Form SWU-101 Version 07July2009 Page 2 of 6 IV. PROJECT INFORMATION 1. In the space provided below, briefly summarize how the stormwater runoff will be treated. Stormwater runoff from the majority of the new development will be routed through the site utilizing vegetative conveyance. Much of this runoff will be conveyed to a level spreader before being discharged from the project area. 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.Identify the regulation(s) the project has been designed in accordance with: ❑ Coastal SW -1995 ❑ Ph lI - Post Construction 3. Stormwater runoff from this project drains to the Cape Fear River basin. 4. Total Property Area: 200 acres 5. Total Coastal Wetlands Area: 0 acres 6. Total Surface Water Area:1.9 acres 7. Total Property Area (4) - Total Coastal Wetlands Area (5) - Total Surface Water Area (6) = Total Project Area+:198.1 acres + Total project area shall be calculated to exclude the following: the normal pool of impounded structures, the area between the banks of streams and rivers, the area below the Normal High Water (NHM line or Mean High Water (MHK) line, and coastal wetlands landward from the NHW (or MHM line. The resultant project area is used to calculate overall percent built upon area (BUA). Non -coastal wetlands landward of the I�THW (or MHi� line may be included in the total project area. 8. Project percent of impervious area: (Total Impervious Area / Total Project Area) X 100 = 2.4 % 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. Basler Informa&m Dramage Area 1 Dramage Area Dranuge Area Dramm a Area Receiving Stream Name Hood Creek Stream Class * C; SW Stream Index Number * 18-66 Total Drainage Area (sf) 8,712,000 ZOVaL On -site Drainage Area (sf) 8,712,000 Off -site Drainage Area (sf) 0 Proposed Impervious Areas 55,829 % Impervious Area** total 2.4% Impervious' Surface Area Drainage Area 1 DramaArea Dratnage Area Draina a Area On -site Buildings/Lots (so 53,896 On -site Streets (sf) 693 On -site Parking (sf) 643 On -site Sidewalks (sf) 597 a ; •. £ Other on -site (sf) g �e� AA i ' Future (sf) Off -site (so _ Existing BUA*** (sf) 147,126 Total (so: p * Stream Class and Index Number can be determined at: http:/%h2o.enr.state.nc.us)Ums/reports ortsWB.html Form SWU-101 Version 07Ju1}2009 Page 3 of 6 Imperoious 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 B UA that will remain after development. Do not report any existing B UA that is to be removed and which will be replaced by new B UA. 11. How was the off -site impervious area listed above determined? Provide documentation. N/A Projects in Union County: Contact DWQ Central Office staff to check if the proiect is located within a Threatened & Endangered Species watershed that may be 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 hU://h2o.enr.state.nc.us/su/bmp forms.htm. 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 hft://h2o.enr.state.nc.us/su/bmp forms.htm. 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 htlp://h2o.enr.state.nc.us/su/msi maps.htm.) 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 latest versions for each submitted application package from hft://h2o.enr.state.nc.us/su/bmp lnifiqls 1. Original and one copy of the Stormwater Management Permit Application Form. 2. Original and one copy of the signed and notarized Deed Restrictions & Protective Covenants 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 htW-Llwww.envhelp.org/]Rages/onestopexpress.hbnl 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/managementfor the project. This is required in addition to the brief summary provided in the Project Information, item 1. 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 ih mile of the site boundary, include the Y2 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 line of tidal waters, and any coastal wetlands landward of the MHW or NHW lines. • 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. Form SWU-101 Version 07July2009 Page 4 of 6 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. 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 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"xl l" copy of. the MRCS 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 SHWT prior to submittal, (910) 796-7378.) 10. A copy of the most current property deed. Deed book: 0489 Page No: 0729 77 I� 11. For corporations and limited liability corporations (LLC): Provide documentation from the NC _I_ 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. hft://www.secretaxy.state.nc.us/CorRorations/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 http://h2o.enr.state.nc.us/su/bmp forms.htm#deed restrictions. 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:Matthew Tones Consulting Firm: Hazen and Sawyer Mailing Address.4011 WestChase Blvd., Suite 500 City:Raleigh State:NC Zip:27607 Phone: (919 ) 833-7152 Fax: (919 ) 833-1828 Email:mjones®hazenandsawyer.com DG PROPERTY OWNER AUTHORIZATION (if Contact Information, item 2 has been felled 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 1a) with (print or type name of organization listed in Contact Information, item 1 b) 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 07Jul 2009 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: 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 seal, )Mew—'1M T> SEAL DEC 2 s 2009 My commission expires X. APPLICANT'S CERTIFICATION I, (print or type name of person listed in Contact Information, item 2) Marty K. Lawing 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 stormwate_ les urjder 15A NCAC 2H .1000, SL 2006-246 (Ph. II - Post Construction) or SL 2008-211. Date: f 0z -I 0 I, �+ Pl dreat -r . W V-1 i }f— �a Notary Public for the State of _N(Or 4 n C-LL rn k nci , County of 2)r k&hs k i ck do hereby certify that M a r fF K . L-o vv � vc a personally appeared before me this 18 day of T)e1�e ca n1�r , a o and /acknowledge the due execution of the application for a stormwater permit. Witness my hand and official seal, (-(7LNl��C_, 4 L(i`W�11 N•��H��IIhIIr�� �r•`o�F-p` es `Vy •yVOL -%q -go 4 • o gigiio . "' t 07• G: �- _� J8�.I dP yAf __AA .• ,�IOV�••0••••••••�•\\,r SEAL My commission expires 0+1911 a0 13 Form SWU-101 Version Muly2009 Page 6 of 6 State Stormwater Management Systems Permit No. SW8 091204 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT LOW 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 Marty K. Lawing, County Manager and Brunswick County Northwest Water Treatment Plant Improvements 4091 Butler Road, Leland, Brunswick County FOR THE construction, operation and maintenance of a 24% low density development in compliance with the provisions of Session Law 2008-211 and Title 15A NCAC 2H .1000 (hereafter referred to singly and collectively 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. The Permit shall be effective from the date of issuance until rescinded and shall be subject to the following specific conditions and limitations: I. DESIGN STANDARDS This permit covers the construction of a total of 55,829 square feet of proposed built - upon area. There is 147,126 square feet of existing impervious area built prior to 1988. The total amount of impervious area with this permit is 202,955 square feet. 2. The overall tract built -upon area percentage for the project must be maintained at no more than 24%, as required by Section .1005 of the stormwater rules. 3. Approved plans, application, supplements and specifications for projects covered by this permit are incorporated by reference and are enforceable parts of the permit. 4. The only runoff conveyance systems allowed will be vegetated conveyances such as swales with minimum side slopes of 3:1 (H:1) as defined in the stormwater rules and approved by the Division. 5. Where the flow rate in a swale exceeds 2 fps, a mechanism to prevent erosion shall be provided at the end of the swaie, prior to discharging into the 50 foot buffer, surface waters or wetlands. 6. No piping is allowed except that minimum amount necessary to direct runoff beneath an impervious surface such as a road or to provide access. 7. Projects covered by this permit will maintain a minimum 50-foot-wide vegetative buffer adjacent surface waters. The width of the buffer is measured horizontally from the normal pool of impounded structures, from the bank of each side of streams or rivers, and from the mean high water line of tidal waters, perpendicular to the shoreline. Page 2 of 5 State Stormwater Management Systems Permit No. SW8 091204 8. All runoff directed into and through the vegetative buffer must flow through the buffer in a diffuse manner. 9. All runoff directed into wetlands shall flow into and through the wetlands at a non -erosive velocity. 10. Roof drains must terminate at least 50 foot from surface waters. II. SCHEDULE OF COMPLIANCE The permittee shall not allow any person, including the permittee, to alter any part of the approved stormwater management system or fill in, alter, or pipe any drainage feature (such as swales) as shown on the approved plans, except for minimum driveway crossings, unless and until the permittee shall have submitted a modification to the permit and received approval from the Division of Water Quality. 2. The permittee is responsible for verifying that the proposed built -upon area does not exceed the allowable built -upon area. 3. 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. 4. 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 the approved plans, regardless of size. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area. e. Further subdivision, acquisition, or sale of the project area, in whole or in part. 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 any vegetative conveyance shown on the approved plan, except for minimum driveway crossings. 5. Swales and other vegetated conveyances shall be constructed in their entirety, vegetated, and operational for their intended use prior to the construction of any built - upon surface. 6. During construction, erosion shall be kept to a minimum and any eroded areas of the swales or other vegetated conveyances will be repaired immediately. 7. The permittee shall at all times provide the operation and maintenance necessary to operate the permitted stormwater management systems at optimum efficiency to include: a. Inspections b Sediment removal. C. Mowing, and re -vegetating of the side slopes. d. Immediate repair of eroded areas. e. Maintenance of side slopes in accordance with approved plans and specifications. Page 3 of 5 State Stormwater Management Systems Permit No. SW8 091204 8. Prior to the sale or subdivision of this project, in whole or in part, the permittee is required to submit a permit modification. 9. Construction of additional built -upon area in excess of 202,955 square feet will require a permit modification. Construction of additional impervious areas such that low density requirements are no longer met must be submitted to DWG? and a permit modification must be issued prior to construction. An engineered system will be required to collect and treat the runoff from all built -upon area associated with the project, including that area permitted under the low density option. 10. Within 30 days of completion of the project, the permittee shall certify in writing that the project has been constructed in accordance with the approved plans. 11. The permittee shall submit all information requested by the Director or his/her representative within the time frame specified in the written information request_ III. GENERAL CONDITIONS Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to an e^forcement action by the Division of Water Quality, in accordance with North Carolina General Statutes 143-215.6A to 143-215.6C. 2. The permit issued shall continue in force and effect until revoked or terminated. 3. 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. 4. 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 Title 15A of the North Carolina Administrative Code, Subchapter 2H.1000; and North Carolina General Statute 143-215.1 et. al. 5. Unless specified elsewhere, permanent seeding requirements for the swales must follow the guidelines established in the latest version of the North Carolina Erosion and Sediment Control Planning and Design Manual. 6. This permit is not transferable to any person or entity except after notice to and approval by the Director. The Director may require modification or revocation and re -issuance of the permit to change the name and incorporate such other requirements as may be necessary. In the event of a name or ownership change, a completed Name/Ownership Change form must be submitted to the Division of Water Quality, signed by the parties involved, and accompanied by appropriate documentation as listed on page 2 of the form. The approval of this request will be considered on its merits, and may or may not be approved. 7. The permittee is responsible for compliance with all permit conditions until the Director approves the permit transfer. Neither the sale of the project, in whole or in part, nor the transfer of common area to a third party, shall be considered an approved permit transfer request. 8. The permittee grants permission to DENR Staff to enter the property for the purpose of inspecting all components of the stormwater management facility. 9. The permittee shall notify the Division in writing of any name, ownership or mailing address changes at least 30 days prior to making such changes. Page 4of5 State Stormwater Management Systems Permit No. SW8 091204 10. The issuance of this permit does not preclude the Permittee from complying with and obtaining any and all permits or approvals 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 prior to receipt of the necessary permits or approvals to do so is considered a violation of NCGS 143-215.1, and subject to enforcement procedures pursuant to NCGS 143-215.6. Permit issued this the twenty-ninth day of December 2009. JNORTROLINA ENVIRONMENTAL MANAGEMENT COMMISSION _g------------ for Sulli s, Director Division of Water Quality By Authority of the Environmental Management Commission Permit Number SW8 091204 Page 5of5 IIWA!Ua,�MVER Environmental Engineers & Scientists Public Water System Project Engineer Certification Form By the signature below I certify: Engineer Signature: Hazen and Sawyer, P.C. 4944 Parkway Plaza Blvd, Sub 375 Charlotte, NC 28217 704-357-3150 Fax:704-357-3152 The referenced public water system project was completed in substantial compliance with the approved engineering plans and specifications, including any provisions stipulated in the Department's plan approval letter or authorization to construct letter, and revised only in accordance with the provisions of Rule .0306. This is a X Full certification Partial certification This certification is based upon inspections conducted daily by the Owner's field representative and periodically by engineers employed by Hazen and Sawyer, who are under my responsible charge. Seal here: Project Name: Northwest WTP Improvements — Brunswick County Serial No: 1 o-00107 �N CAROL SEAL ' 16797 Engineer Name(Print): Jay Jackson Date: C? ^ Water System Name: Brunswick County Water System Mail completed form to: Public Water Supply Section 1634 Mail Service Center Raleigh, NC 27699-1634 Cc: Mr. John Nichols, PE, Mr. Glenn Walker, Mr. George Brandon, Brunswick C-,�I� Ms. Diane Williams, NC Public Water Supply Section oc� 7011 BY: Johnson, Kelly From: Johnson, Kelly Sent: Tuesday, October 11, 2011 9:07 AM To: 'jjackson@hazenandsawyer.com' Subiect: Northwest WTP, SW8 091204 Jay, Please submit the Plan Revision form, htto://aortal.ncdenr.org/web/wa/ws/su/statesw/forms docs. Thanks, Kelly *** My email has changed to kellv.n.iohnsonOncdenr.eov K.GLL0hKS0Yt, Kelly Johnson Environmental Engineer Division of Water Quality Stormwater Permitting 127 Cardinal Drive Extension Wilmington, NC 28405-384S Office: 910.796.7331 Fax: 910.350.2004 E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to third parties. NCDENR North Carolina Department of Environment and Natural Resources Division of Water Resources Beverly Eaves Perdue Governor MARTY LAWING P O BOX 249 BOLIVIA, NC 28422 Dear Sir/Madam: Thomas A. Reeder Director 09/ 16/2011 Dee Freeman Secretary Re: Final Approval Final Approval Date: 09/16/2011 NORTHWEST WTP IMPROVEMENTS - BRUNSWICK COUNTY Serial No.: 10-00107 Water System No.: NC0410045 BRUNSWICK COUNTY The Department received an engineer's certification statement and an applicant's certification statement concerning the above referenced project. The engineer's certification verifies that the construction of the referenced project has been completed in accordance with the engineering plans and specifications approved under Department Serial Number 10-00107. The applicant's certification verifies that an Operation and Maintenance Plan and Emergency Management Plan have been completed and are accessible to the operator on duty at all times and available to the Department upon request and that the system will have a certified operator as required by 15A NCAC 18C .1300. Me Department has determined that the requirements specified in 15A NCAC 18C .0303(a) and (c) have been met and, therefore, issues this Final Approval in accordance with Rule .0309(a). If Public Water Supply can be of further service, please call (919) 733-2321. cc: Debra Benoy, P.E., REGIONAL ENGINEER BRUNSWICK COUNTY HEALTH DEPARTMENT HAZEN AND SAWYER, PC - CHARLOTTE Public Water Supply Section - Jessica C. Godreau, Chief 1634 Mail Service Center, Raleigh, North Carolina 27699-1634 Phone: 919-733-2321 \ FAX: 919-715-4374 \ Lab Form FAX: 919-715-6637 \ Internet: An Equal Opportunity \ Affirmative Action Employer Sincerely, J. Wayne Munden, P.E., Head Technical Services Branch Public Water Supply Section C�IVET-1% Nil BY: ECG Carolina ou 0 7 20#1 a, �(ral`y i BY: State of North Carolina Department of Envirc mment and Natural Reso=es Wilmington Regional Office Deverly Faves Perdue, Governor bee Freeman, Secretary FAX COVER SHEET Date: 14LL, No. Of Pages: (excluding cover)T., YrATtRFJ From; � CO: CO: NC RENR FAX #: — S 1= — 9 ?S' FAX#: 910-350-2004 REMARKS: _ ;�2 LO 127 Cardinal Drive Eximlon, Wilmington, N.C. 29406-3W TeIcPhono (910) 796.7215 Faz (910) 350-2004 An Equal Opportunity AM -attire Action Employer � >K 9 :S30dd S5£ WE W101 >K � �3LU NO X1 XH 9 M5£,E WCE861616 Rd 010 6E-OdQ dQ G 3dA1 SNOVd 3WI1 X1 N3AI303H 1NV1S 31VO :K � >K >X QNNS NOE 09£ 016 WON : NN >X Rd 010 df l 600e-H-03a >K MOM NOIIOVSNVdl � .IO 'd I 0 STATE OF NORTH CAROLINA BOOK 489 M,. 729 COUNTY OF BRUNSWICK THIS WARRANTY DEED, blade and entered into this the 31st day of December, 1981, by and between ADDIE W. BUTLER (Widow) of Brunswic ounty, North Carolina, hereinafter referred to as the party the first paR�p r RUNSWICK COUNTY, a body politic and su �ision oA' he State ofro)Wzhereinafter referred as the party((v��second part; D W 1%NESSET11 THAT for and in consideration of the sum of FIVE HUNDRED THOUSAND ($500,000) DOLLARS and other valuable considerations, in hand paid by the said party of the second part, the receipt of which is hereby acknowledged, the said party of the first part, O Grantor, s bargained and sold, and by these presents does hereby give,.4'ant, bargain, convey unto the party of the second D pa"o Grantee`' R fee simple, E'ER, to the terms and 'ditions hereina l�set forth, all that certain tract or parcel of land located in Northwest Township, Brunswick County, North Carolina, and more particularly described as follows; 0.1 cj m o �h 1 3 O $O1�Zi°xN Carolina a BEGINNING at an iron pipe in the eastern right-of-way line of a proposed entrance road to the property, said iron pipe and place and Irnint of Beginning being from the intersection of the center lines of -SR 1426 and SR 1.160. S 20 degrees 45 minutes 07 seconds W. along the centerline of SR 1460 1198.94' to a pipe in the cen line of SR 1960; Thence, perpendicular to Lhe of SR 1460, easterly 30' to �a pipe in ight-of,-way line of SR (60; Thencminutes 12 seconds Q74-;7J R- 492. long the eastern rig ay line of the proposed entrance road to anpipe in the eastern right-of-w•ay line of the proposed entrance road; Thence, continuing with the eastern right-of-way line of the proposed entrance road S 29 degrees 23 minutes 30 seconds E 465.05' to the Place and Point of Beginning; Thence from the Beginning Point, R=1427.11' S 10 degrees 05 minutes E C11. 943.75' to an iron pipe; Thence S 9 degrees 19 minutes 30 seconds W 2978.08, to an iron pipe in the centerline of the North Carolina Natural Gas Pipeling Easement; Thence s 73 degrees 07 minutes 47 seconds W 1103.02' to a new iron rod in the northern right-of-way line of the railroad right-o Thence with the northern right-of-way line of ad N 64 degrees 42 minutes 17 econds W 1 �'�� Dint in the intersection �l ^� srara orb MA ReOl Estate jQRT G = .u,.�.., %-,4nn nQl± ,_s V aoosc 48��•= 738 of the northern right-of-way line of the railroad right-of-way and the centerline of the run of Hoods Creek as plotted from the Brunswick County Tax Department's Tax Map; Thence, with the centerline of the run of Hoods Creek northerly, as plotted from the DrZhe' ck County Tax Department's Tax Map, more than 3to a point in the intersection of the centerf the run of floods Creek and the boundary lin Butler prAK: with the Hoffman property; The with the Hoif o the the centerline of run o .,foods Creek �f�'gayg 49 minutes 5 econds E w iron ro offman e; Thence, c with the Hoifm�'line 89 degrees 49A�Pipc� 53 seconds E 310.23' to an existing irothe Hoffman line; Thence, leaving the Hoffman line S 18 degrees 55 minutes 15 seconds E 95, to an iron rod; Thence S 36 degrees 10 minutes 15 seconds E 135' to an iron rod; Thence 8 5 degrees 10 minutes 15 seconds E 463' to an iron rod; Thence 8 75 degrees 55 minutes 15 seconds E 165' to an iron rod; Thence S 4 degrees 56 minutes 30 seconds E 256.57' to an existing iron pipe; Thence N 86 degrees 02 minutes E 1016.12' to a Bolt; Thence N O5 deg- 30 minutes 33 seconds W 213.85' to a new iron pe and 15 inch Gum; Thence S 59 degrees 46 minute 801.41' to a new iron rod in the center of a Iig 'ood stump• T 9 degrees 40 minutes 49 s ads W 684.15' //T�QQ��,,��rod: Thence N 80 de s 19 m es 11 secon �Sp/7J� to an iron rod; i" ce N 7 deg 26 minutes E Iff�1 an iron rod; nce N 11 degr W inutes E 114.10' o an iron rod; Thence N 29 de 23 minutes 30 seconds W 44.93' to an iron rod; hence S 82 degrees 34 minutes E 74.96' to the Place and Point of SEGIMING. And containing 200 acres more or less all according to a survey by G. Douglas Jefferys, RLS dated May & June, 1981, Updated December, 1981. This conveyance is made SUBJECT to the following terms and conditions: 1. The Gtor, party of the first part, reserves unto h, her succd�sors, heirs and assigns, the right use, with th its successors and assi that certain ma d proposed to be structe��• the Grantee tern boundary o s property eby conveyed, for s and egress and from the pr ty conveyed and the property of the Grantor locat �n the eastern boundary of the described property in t is conveyance. 2, The Grantor, party of the first part, reserves unto herself, her successors, heirs and assigns, the right to enter upon the described property for a period until and through December. 1983, but no longer, in order to take and remove all the merchantible timber located on the property described, SO LONG AS, the said act iv of the Grantor, her agents, successors, heirs and iSns, in cutting and removing the said timber not interfere with, hinder or delay the constr oa and opera of the water treatment plants d its appurten a constructed and oe�r� on th�;pr�tY con N U' �� a4 D �' D �O BooK 489 P.m- '%.:1 3. The Grantor, party of the first part, reserves unto herself, her successors, heirs and assigns, the right of ingress and egress to and from the NCNG gas pipeline and the railroad located on the property conveyed, large enough for the movement of tractor- trailer rigs anu other heavy equipment at such place QO on the property as may be mutually agreed to by the parties hereto. 4. Th party of tbc- first part, reserves unto horse es_ors, hairs and assigns, and (orzeeifically do the ASCA tobacco acreage oundage allotment nod to this property to tee. TO HAVE AND TO HOLD the aforesaid tract or parcel of land to its own use and behoof, and that of its successors and assigns, forever, SUBJECT HOWEVER, only to the foregoing terms and conditions ol .this conveyance. in fee simple. Q 2ND the Grantor, party of the first part, covenants with Aegrantee, par/¢,,/, off the second part, that the Grantor is se d of the remisels Fla Z�f has the right to convey the (#e in fee sim that title isle and free and clear of all encumbrances, anf.hat Grantor will warrant and defend the title against the lawful claims of all persons whomsoever. IN WITNESS WHEREOF. the Grantor has hereunto set he: hand and seal, this, the day and year first above written. �O (Seal "Iff1e) ' D '1 �A. 111\VQfQpx1-§--Y STATE OF NORTH CAROLINA son x 4 f;t;; a COUNTY OF BRUNSWICK I. YPA! ,a 7 S4aas a Notary Public do hereby certify that ADDIE F. BUTLER personally appeared before me this dale and acknoml.lged the due execution of the foregoing instrument for the pures therein set forth. WITNESS,, CCIand and Notar this /�the � +day of c lJ" a 1 �gi1 �t51) 1 Not y Pub (SEAL) My commission expires: �O My CM-M- itm &;1-re, Roy. 14. 19 s� STATE OF NORTH CAROLINA. erunswiek The Foregoing Certifiate(s) of Kati nnnrlpr, y• Opp _ . v .��•,'. Sys. � '••.,��r coup+ CkXare) certified to be correct. Recorded chi. 5th day of �S 0 I9 $Zat O R�D1. fd Rouen J. Ro9msan N J C I, Action Id. SAW-2009-01615 U.S. ARMY CORPS OF ENGINEERS WILMINGTON DISTRICT County: Brunswick U.S.G.S. Quad: Leland NOTIFICATION OF JURISDICTIONAL DETERMINATION Property Owner: Brunswick_ County c/o Glenn Walker Address: 4091 Butler Road Leland, NC 28451 Agent: Harvey E. Clifton, Jr. Coastal Environmental Consultins, Inc. Address: P.O. Box 15102 Wilmington, NC 28408 Telephone No.: (9101791-6411 Property description: Size (acres) --1 acre Nearest Town Leland Nearest Waterway UT to Hood Creek River Basin Cape Fear USGS HUC 03030005 Coordinates N 34.309939 W-78.107153 Location description The project area site is located in wetlands adjacent to an unnamed tributary to Hood Creek at 4091 Butler Road Leland, Brunswick County, North Carolina. Parcel ID N:01500080. Indicate Which of the Following Auply: A. Preliminary Determination _ Based on preliminary information, there may be wetlands on the above described property. We strongly suggest you have this property inspected to determine the extent of Department of the Army (DA) jurisdiction. To be considered final, a jurisdictional determination must be verified by the Corps. This preliminary determination is not an appealable action under the Regulatory Program Administrative Appeal Process ( Reference 33 CFR Part 331). B. Approved Determination There are Navigable Waters of the United States within the above described property subject to the permit requirements of Section 10 of the Rivers and Harbors Act and Section 404 of the Clean Water Act. Unless there is a change in the law or our published regulations, this determination may be relied upon for a period not to exceed five years from the date of this notification. X There are waters of the U.S. including wetlands on the above described project area subject to the permit requirements of Section 404 of the Clean Water Act (CWA)(33 USC § 1344). Unless there is a change in the law or our published regulations, this determination may be relied upon for a period not to exceed five years from the date of this notification. We strongl y suggest you have the waters of the U.S. including wetlands on your property delineated. Due to the size of your property and/or our present workload, the Corps may not be able to accomplish this wetland delineation in a timely manner. For a more timely delineation, you may wish to obtain a consultant. To be considered final, any delineation must be verified by the Corps. _ The waters of the U.S. including wetland on your project area have been delineated and the delineation has been verified by the Corps. We strongly suggest you have this delineation surveyed. Upon completion, this survey should be reviewed and verified by the Corps. Once verified, this survey will provide an accurate depiction of all areas subject to CWA jurisdiction on your property which, provided there is no change in the law or our published regulations, may be relied upon for a period not to exceed five years. X The waters of the U.S. including wetlands have been delineated and surveyed and are accurately depicted on the plat signed by the Corps Regulatory Official identified below on October 27, 2009. Unless there is a change in the law or our published regulations, this determination may be relied upon for a period not to exceed five years from the date of this notification. Page 1 of 2 l . r J w -'- ,Action ID: SAW-2009-01615 There are no waters of the U.S., to include wetlands, present on the above described property which are subject to the permit requirements of Section 404 of the Clean Water Act (33 USC 1344). Unless there is a change in the law or our published regulations, this determination may be relied upon for a period not to exceed five years from the date of this notification. X The property is located in one of the 20 Coastal Counties subject to regulation under the Coastal Area Management Act (CAMA). You should contact the Division of Coastal "Management in Wilmington, NC at (910) 796-7215 to determine their requirements. Placement of dredged or fill material within waters of the US and/or wetlands without a Department of the Army permit may constitute a violation of Section 301 of the Clean Water Act (33 USC § 1311). If you have any questions regarding this determination and/or the Corps regulatory program, please contact Teresa Russell at 910-251-4725 C. Basis For Determination The site exhibits wetland criteria as defined in the 1987 Corps Wetland Delineation Manual and is adjacent to an unnamed tributary to Hood Creek. a Section 10 Navigable Water of the U.S. This determination is based on information submitted by Gene Clifton of Coastal Environmental Consulting. Inc. and a site visit by Teresa Russell of the U.S. Armv Corers of Engineers on September 2.2009. D. Remarks E. Attention USDA Program Participants This delineation/determination has been conducted to identify the limits of Corps' Clean Water Act jurisdiction for the particular site identified in this request. The delineation/determination may not be valid for the wetland conservation provisions of the Food Security Act of 1985. If you or your tenant are USDA Program participants, or anticipate participation in USDA programs, you should request a certified wetland determination from the local office of the Natural Resources Conservation Service, prior to starting work. F. Appeals Information (This information applies only to approved jurisdictional determinations as indicated in B. above) This correspondence constitutes an approved jurisdictional determination for the above described site. If you object to this determination, you may request an administrative appeal under Corps regulations at 33 CFR part 331. Enclosed you will find a Notification of Appeal Process (NAP) fact sheet and request for appeal (RFA) form. If you request to appeal this determination you must submit a completed RFA form to the following address: District Engineer, Wilmington Regulatory Division Attn: Teresa E. Russell Wilmington Regulatory Field Office 69 Darlington Ave Wilmington, North Carolina 28403 In order for an RFA to be accepted by the Corps, the Corps must determine that it is complete, that it meets the criteria for appeal under 33 CFR part 331.5, and that it has been received by the District Office within 60 days of the date of the NAP. Should you decide to submit an RFA form, it must be received at the above address by December 26, 2009. **It is not necessary to submit an RFA form to the District Office if you do not object to the determination in this correspondence.** — I ; N „ n Corps Regulatory Offici Date October 27, 2009 Expiration Date October 27, 2014 The Wilmington District is committed to providing the highest level of'support to the public. To help us ensure we continue to do so, please complete the Customer Satisfaction Sti vey located at our website at hg /Jregulatory. usacesurvev. com! to complete the survey online. Copy furnished: - Chad Coburn, NCDENR-DWQ, 127 Cardinal Drive, Wilmington, NC 28405 -Miles McCall c/o Withers & Ravenel, 1410 Commonwealth Dr., Unit 101, Wilmington NC, 28403 -Jay Jackson c% Hazen & Sawyer, P.C., 4944 Parkway Plaza Blvd. Suite 375, Charlotte, NC 28217 STORMWATER SUBMITTAL REQUIREMENTS LOW DENSITY ,= ; Subdivisions, Curb Outlet System, Non -subdivision Objectives i { A. Limit amount of built -upon surfaces per the most current rul B. No collection systems (limited piping -only enough to ge under a road)no inverted crown streets) C. ,/Sheet flow D. / No area of the project of such high density that runoff threatens water quality. (i.e., pocket of high density). II. What makes up a complete low -density application package? A. ,/Two sets of layout & grading plans with road details and a swale drainage area map for curb outlet systems. Unrelated plan sheets such as water/sewer profiles or details are not B. �ecessary. (Additional sets of plans may be requested for projects in certain counties) ompleted application with supplement(s), SWU-101, SW401-Low Density, SW401-Curb Outlet, SW401-Grassed Swale. C,---Deed restrictions, if applicable. D--,--,Curb outlet swale calculations if applicable. E.--- Chlorides test results must be provided if the project is within'/ mile of SR waters (Phase 11). (This is only required to test out of SR water treatment requirements) III. BIMS entry (for DWQ use only) Enter & track submittal dates, add info requested/received dates, permit issue dates, and drainage area info. Best done after the add info letter is written and before sending permit up for signature. IV. Shell documents (for DWQ use only) Permit shells: s:\wqs\stormwater\shellsllowother (for non -subdivisions) s:\wgs\stormwater\shells\lowsub (for subdivisions with no C&G) s:\wqs\stormwater\shells\lowsubcg (for subdivisions w/C&G) Calculations: s:\wgMstormwater\excel spreadsheets\curb&gutter V. Review Procedure- look for consistency between the various elements of the package- application, plan and calculations. A. APPLIOATION 1. ✓Original signature required. Photocopied signatures cannot be accepted. 2. , Wan agent signs the application, a signed letter of authorization from the applicant must be provided which includes the name, title, mailing address and phone number of the p6 son signing the letter. 3. Correct supplemenis are provided - iow density andfor curb outlet supplement and grassed swale supplement (no low density supplement needed for projects that do not propose to subdivide and sell lots.) 4. � uilt-upon areas must be reported in square feet in Section 111.6 of the application. 6--Within Phase II counties, BUA limits are 12% within'/ mile and draining to SR waters, and 24% for all others. 6. deceiving stream name and classification. This is important because of the various density nsity limits. 7. LAection 111.6 is filled in -cannot be left blank. For low density, only one column is filled in unless either a pocket of high density is formed, or the project drains to different classifications of water bodies, which result in different BUA limits. 8.✓ If the applicant is a corporation, partnership or LLC, look it up on the Secretary of State Corporations Database. Make sure corporation is spelled correctly (capitalization and punctuation matter) and that the person signing the application is at least a vice- president in the corporation, a General Partner in the partnership, a member in a member -managed LLC, or the manager of a manager -managed LLC. Need documentation to support if the Articles of Incorporation do not list the members or managers of the LLC. if an agent signs, then a letter of authorization is needed from the president, vice president, general partner, member or manager. -9—For subdivided projects, a signed and notarized deed restriction statement must be provided. B. CALCULATIONS t. ----Found at the top of page 2 of the low density supplement. Follow the formula to get the allowable BUA per lot. For non -subdivision projects, a supplement form is not required and the calculations in Section 111.6 of the application will suffice. For subdivision projects with varying lot sizes and BUA's per lot, the calculation would only be done to the point that the total BUA available for the lots is determined. Do not divide by the number of lots. If wetlands are present, the applicant must calculate the site area to be used in the BUA per lot0�c.0 lation by following the calculation methods outlined in the wetlands policy. vl (-,o .^ L- 8------ For curb outlet systems, swale velocity calculations are required, to include the individual swale drainage area, the built -upon area within each drainage area, and the Rational C-value calculated for each DA. f a pocket of high density is formed, the application must include an engineered control suitable for the classification of the receiving waters. tRA C. PLANS- Plan sheets should be kept to a minimum. In general, depending on the size of the project, the plan set should consist of 1-4 sheets with the following information provided: A . DevelopmentlProject Name „2. Engineer name and firm. �' • ^ `3� Legend containing all of the symbols used on the plans. r/k!' North Arrow G �k %„5.— Location Map with nearest intersection of two major roads shown. ajor road is any 1, 2, or 3 digit NC, US or interstate highway. /-Jr Z fit . 4.. \-S.—~Scale- standard engineering scale, no off-the-wall stuff. �✓ -- Date ✓� f'J° d $..._.._..-Revision number and date, if applicable.. a------� -- V Original contours, proposed contours,;'spot elevations 'ffnished floor elevations,pipe ° \ inverts, swale inverts,( etc. . _ �___ _. _ ....:......._ .._.� r' 10 �) Existing drainage (piping, swales, ditches, ponds, etc.), including off -site. Include a map `---,-J delineating the offsite drainage areas. 11✓ Property/Project boundary lines, bearing & distances. 42-� Mean High Water Line, or Normal High Water line if applicable. 13. Drainage easement location and width. Lommao Wlt , 411 Vr Wetlands, whether they are disturbed or not, are delineated, or provide a note on the plans that none exist. Provide a copy of the wetlands delineation map signed by the Corps of Engineers, or include a copy of the unsigned delineation map that was submitted to the Corps. 15,/Details forthe roads, parking area, cul-de-sac radii, sidewalk widths, curb and gutter, all dimensions & slopes. Note if dimensions arefa of ua to race of curb (FC-FC) or back of curb to back of curb (BC -BC). - %ja IVIEW I.6-- Apartment / Condo development- Provide_a typical,building footprint with dimensions and note all concrete and wood deck areas. `4�be drainage area for each curb outlet swale is clearly delineated and numbered to match up to the calculations and supplement. Only swales that actually receive road runoff have to be curb outlet swales with 5:1 side slopes. Delineation is best done as a separate plan sheet. `curb outlet swale detail noting the 5:1 or flatter side slopes, the 100' minimum length and the type of grass to be planted on the side slopes. 6'Ip A level spreader is provided at the end of all swales that will drain into wetlands or surface waters. Level spreader O & M is provided. .For those low density projects within '/ mile of and draining to SA or SR waters, additional BMP's are required to be shown on the stormwater plans such that no discharge from the site occurs. This is done on behalf of the Division of Marine Fisheries. -'nor Phase II low density projects draining to SR waters make sure that the project complies with the following: a. No new points of stormwater discharge. Diffuse flow of stormwater at a non - erosive velocity to a vegetated buffer capable of providing effective infiltration of the runoff from the 1 year 24 hour storm shall not be considered a direct discharge. b. No increase in the volume of stormwater flow or the capacity of an existing stormwater conveyance system that drains to SR waters. c. Modifications to existing stormwater conveyance systems within the contributing drainage basin do not increase the net amount or rate of stormwater discharge through existing outfalls to SR waters. 01 FeC4 D&D Wig' /•� ��` i9A.D.% For DENR Use ONLY �� North Carolina Department of Environment and Reviewer �l ►13' ii1_ Natural Resources Submi 12 - 0 —SCOPE NCDENR Request for Express Permit Review Time: 10 : e0- Confirm: _ 1 2 — 8 FILL-IN all the information below and CHECK the Permit(s) you are requesting for express review. FAX or Eman me completed form to express Coordinator along with a completed DETAILED narrative, site plan (PDF file) and vicinity man (same items expected in the application package of the project location. Please Include this form in the application package. ., ` iE '"`r �4c- 1l0 Or l� • Asheville Region Alison Davidson 828-296-4698,g ison.davidson®Acmail net �:�W 4 � ad • Fayetteville or Raleigh Region -David Lee 919-791-4203, david/eeOn mai/.net 1 ; A � �� — 12 Mooresville & -Patrick Grogan 704-663-3772 or Patrick orooan0nigmail net Washington Region -Lyn Hardison 252-946.9215 or lyn-hardison9kntvmall net Wilmington Region -Janet Russell 910-350-2004 orlanet russefflAcmail net C s r1 a •!" NOTE: Projed application received after 12 noon will be stamped in the following work "�,� Project Name: NORTHWEST WATER TREATMENT PLANT IMPROVEMENTS County: BRUNSWICK Applicant: JOHN NICHOLS Company: BRUNSWICK COUNTY Address: BUILDING G. 20 REFERENDUM DRIVE, NE City: BOLIVIA. State: NC Zip: 28422- G Phone: 910-253-2657 Fax::910-253-4304 Email: 'nii cholsCc�brunsco.net `s ' Physical Location:4091 BUTLER ROAD, LELAND, NC 28451 Project Drains into HOOD CREEK waters —Water classification C, SW (for classification see-hitp://h2o.enr.state.nc.uAims/reoorts/reoortsWB.html) Project Located in CAPE FEAR River Basin. Is project draining to class ORW waters? N , within % mile and draining to class SA waters N or within 1 mile and draining to class HQW waters? N "V' :� ' , .i Y E Engineer/Consultant: MATTHEW JONES Company: HAZEN AND SAWYER Address: 4011 WESTCHASE BLVD, SUITE 500 City: RALEIGH, State: NC Zip 27607-_ 1 ' Phone: 919-833-7152 Fax::919-833-1828 Email: miones@llazenandsaw-ver.com DEC 0 8 2009 SECTION ONE: REQUESTING A SCOPING MEETING ONLY ElScoping Meeting ONLY ❑ DWQ, ❑ DCM, ElDLR, ElOTHER: PROJ # OWQ SECTION TWO: CHECK ONLY THE PROGRAM (S) YOU ARE REQUESTING FOR EXPRESS PERMITTING ❑ 401 Unit ❑ Stream Origin Determination: _ # of stream calls — Please attach TOPO map marking the areas in questions ❑ Intermittent/Perennial Determination: _ # of stream calls — Please attach TOPO map marking the areas in questions ❑ 401 Water Quality Certification ❑ Isolated Wetland (_linear ft or _acres) ❑ Riparian Buffer Authorization ❑ Minor Variance ❑ Major General Variance ® State Stormwater ❑ General ❑ SFR, ❑Bkhd & Bt Rmp, ❑ Clear & Grub, ❑ Utility ® Low Density ❑ Low Density -Curb & Gutter _ # Curb Outlet Swales ❑ Off -site [SW (Provide permit #)] ❑ High Density -Detention Pond _ # Treatment Systems ❑ High Density -Infiltration _ #Treatment Systems ❑ High Density-Bio-Retention _ # Treatment Systems ❑ High Density—Stormwater Wetlands # Treatment Systems[] High Density - Other _# Treatment Systems /❑ MODIFICATION: ❑ Major ❑ Minor ❑ Revision SW (Provide permit #) ❑ Coastal Management ❑ Excavation & Fill ❑ Bridges & Culverts ❑ Upland Development ❑ Marina Development ❑ Structures Information ❑ Urban Waterfront ® Land Quality ® Erosion and Sedimentation Control Plan with 5 acres to be disturbed.(CK # (for DENR use)) SECTION THREE — PLEASE CHECK ALL THAT IS APPLICABLE TO YOUR PROJECT (for both scoping and express meeting request) Wetlands an Site ® Yes ❑ No Wetlands Delineation has been completed: ® Yes ❑ No US ACOE Approval of Delineation completed: ® Yes ❑ No Received from US ACOE ® Yes ❑ No Fee Split for multioleDermlts: (Check# Buffer Impacts: ® No ❑ YES: acre(s) Isolated wetland on Property ❑ Yes ® No 404 Application in Process w/ US ACOE: ❑ Yes ® No Permit For DENR use only Total Fee Amount S SUBMITTAL DATES Fee I SUBMITTAL DATES Fee CAMA $ 1 Variance ( Maj; Min) 1 $ SW (❑ HD, ❑ LD, Gen) 1 $ 401: $ LQS $ Stream Deter,_ $ rd 4,0 'T—�Norblet o n 12- c9 NCDENR EXPRESS September 2008 !!*-4V .$_I_ 16.4* 46 10. RAZEN AND SAWYER Environmental Engineers & Scientists December 8, 2009 Ms. Janet Russell North Carolina Department of Environment and Natural Resources Express Permitting Wilmington Regional Office 127 Cardinal Drive Extension Raleigh, NC 27609 Hazen and Sawyer, P.C. 4011 WestChase Blvd. Suite 500 Raleigh, NC 27607 (919) 833-7152 (919) 833-1828 (Fax) Re: Brunswick County, North Carolina Northwest Water Treatment Plant Improvements Request for Express Permit Review H&S Job No.: 30994 Dear Ms. Russell: Please find enclosed the Request for Express Permit Review. Also enclosed is a stormwater narrative, vicinity map, and overall site plan. We are requesting express permit reviews for state stormwater management, utilizing the low density development option, and an erosion and sedimentation control plan. Depending upon your availability, a representative from Brunswick County and I would like to schedule a meeting to discuss the permit review and submit the permit applications on December 16t" or 17t". If you are not available on either of those dates, please let me know so that we can make alternative arrangements. Thank you for your time and consideration. Please call me if you have any questions or require any additional information. Sincerely, HAZEN AND SA R, P.C. Matthew P. Jones, El Assistant Engineer 919-833-7152 Now York, NY - Philadelphia, PA - Raleigh, NC - Charlotte, NC - Greensboro, NC - Chadeston, SC - Atlanta, GA - Fairfax, VA - Hampton Roads, VA - Baltimore, MD - Cincinnati, OH - Hollywood, R. - Boca Raton, FL- Miami, FL 3sn J i I 0 '.. sSBtBY Moog Owb Oggg F 0. pvw,z N At jz k cy DIR I 1 p£ ,tq .£-0 il'99Y 1�11 .GV ,£Y 1£-9 a �aN � J - r Overview The Brunswick County Public Utilities Department has proposed to expand the Northwest Water Treatment Plant in order to better provide potable water to the residents of Brunswick County. The improvements to the facility will involve construction of a 51,100 ft2 ground level potable water storage tank), a clearwell a storage building, 1,340 1,000 ft2 metering vault, a 1,800 ft2 chemical ft2 of asphalt pavement, and 490 ft2 of sidewalk. Underground piping l and utilities will also be installed as part of the plant improvement in order to integrate the _ - facllltles with the existing treatment plant infrastructure. g e new r, 1) Site Description r The Northwest Water Treatment Plant parcel is 200 acres and is located within Brunswick ��•�. �. �}�a County, NC. The site can be accessed from Butler Road, south of Mt Misery Road. The parcel is � predominantly forested, with grassed areas surrounding the existing buildings. The site ,ter currently contains 3.4 acres of impervious surface, including buildings, closed storage tanks' parking, and roadways. Additionally, open tanks occupy 1.86 acres of the site and do not generate any runoff. Stormwater is conveyed through the site via a storm sewer system and vegetated conveyance. The original treatment plant was constructed in 1983 and consequently was not subject to stormwater treatment regulations. Water Resources The project site is located within the Cape Fear River Basin. Hood Creek serves as the western boundary of the parcel and receives runoff from the entire site. Additionally, there is an. unnamed tributary to Hood Creek located near the northern boundary of the parcel. All runoff ultimately leaves the site via Hood Creek near the northwestern corner of the parcel. A wetland is located near the northeastern boundary of the site. This wetland was delineated.by Harvey Clifton of Coastal Environmental Consulting, Inc. as a 404 jurisdictional wetland and,subsequently confirmed by Teresa E. Russell, the Corps Regulatory Official. The construction limits for this project are located entirely outside the wetland boundary. Although surface water associated with Hood Creek and the unnamed tributary are contained within the Northwest Water Treatment Plant parcel, the stream boundaries were not delineated for the purpose of defining the total project area, since they are located a substantial distance away from the construction area and are not expected to have a substantial impact on the impervious percentage of the project. Similarly, stormwater calculations were confined to the parcel boundaries. Off -site drainage consists of the entire watershed for Hood Creek. All drainage that flows through the currently proposed development area is contained within the parcel boundary. Existing Stormwater Conveyance and Treatment Runoff from all parking and roadway surfaces is collected by catch basins and conveyed by a storm sewer system. The storm sewer discharges onto a rip rap apron and is subsequently conveyed via overland flow to Hood Creek. Runoff from the area north of the main parking and driveway area is conveyed primarily by overland flow and vegetative channels. Proposed Stormwater Conveyance and Treatment Because the site is characterized as low -density development, based upon the impervious percentage of the parcel, and localized areas of high density do not directly discharge to surface waters, no structural stormwater BMPs are being proposed for this site. Following development, the site will consist of 2.4% impervious surfaces. Runoff will be conveyed as vegetated surface flow through much of the site, maximizing opportunities for infiltration and minimizing runoff volumes. /_LD \� Runoff from the proposed 1,800 ft2 chemical storage building and associated driveway and sidewalk will be collected by the existing storm sewer system. Hydraulic calculations indicate that the storm sewer system is adequately sized to convey increased flow from these areas and their incorporation is not expected to result in the degradation of existing stormwater treatment. Runoff from the proposed 51,100 ft2 clearwell and 1,000 ft2 metering vault will be conveyed via overland sheet flow and vegetative stormwater conveyance channels. In order to maintain non -erosive flows into the wetland, a velocity dissipation structure will be installed east of the proposed clearwell. This structure will receive runoff from the majority of the proposed clearwell and will diffuse stormwater flows over a wide area, thereby reducing the flow velocity. Anticipated 10-yr flow velocities into the wetland are less than 2 ft/s. Temporary measures shall be implemented during construction to limit erosion and control sediment in accordance with the North Carolina Erosion and Sediment Control Planning and Design Manual. Conclusions The proposed design is for the incorporation of 1.28 acres of impervious area for the Northwest Water Treatment Plant improvement project. The site is characterized as a low -density development due to the low percentage of impervious area and lack of direct stormwater discharge into surface waters. Vegetative conveyance has been incorporated to the maximum extent practical and a velocity dissipation structure is proposed to minimize the velocity of water flowing into the wetland. Based on these characteristics, the proposed development is expected to satisfy all NCDENR DWQ stormwater requirements. r I H O z r- Stormwater Management Permit Application Brunswick County, NC Northwest Water Treatment Plant Leland, NC Prepared for: DEC 2 8 2�09 gY: !„Wij 1a0�' NC Department of Environment and Natural Resources Division of Water Quality December 2009 Prepared by: Hazen and Sawyer, PC Raleigh, NC Attention: Mary Jean Naugle DEC 2 3 2009 iJflM L'll\L SOM Environmental Engineers do Scientists L� rf it izq W LL 0 LU r Table of Contents NCDENR DWQ Stormwater Management Permit Application Form .................................... i Tableof Contents...................................................................................................................1 StormwaterNarrative............................................................................................................2 Stormwater Overview Figure.................................................................................................3 USGSSite Map.......................................................................................................................4 NRCSSoil Map........................................................................................................................5 Parcel Drainage Description...................................................................................................6 ParcelRunoff Hydrographs....................................................................................................7 Storm Sewer Hydraulic Calculations......................................................................................8 PrecipitationIDF Data............................................................................................................9 Channel Design Calculations..................................................................................................10 Velocity Dissipation Structure Calculations...........................................................................11 LevelSpreader Supplement...................................................................................................12 LowDensity O&M Agreement...............................................................................................13 PropertyDeed........................................................................................................................14 WetlandDelineation..............................................................................................................15 DesignDrawings.....................................................................................................................16 } DEC 2 8 2009 BY; Overview The Brunswick County Public Utilities Department has proposed improvements to the Northwest Water Treatment Plant in order to better provide potable water to the residents of Brunswick County. Stimulus funds are involved in the construction of this project. The improvements to the facility will involve construction of a 51,100 ft2 clearwell (a ground level potable water storage tank), a 1,000 ft2 metering vault, a 1,800 ft2 chemical storage building, 1,340 ft2 of asphalt pavement, and 600 ft2 of sidewalk (Figure 1). Underground piping and utilities will also be installed as part of the plant improvement in order to integrate the new facilities with the existing treatment plant infrastructure. Site Description The Northwest Water Treatment Plant parcel is 200 acres and is located within Brunswick County, NC. The site can be accessed from Butler Road, south of Mt Misery Road. The parcel is predominantly forested, with grassed areas surrounding the existing buildings. The site currently contains 3.4 acres of impervious surface, including buildings, closed storage tanks, parking, and roadways. Additionally, open tanks occupy 1.86 acres of the site and do not generate any runoff. Stormwater is conveyed through the site via a storm sewer system and vegetated conveyance. The original treatment plant was constructed in 1983 and consequently was not subject to stormwater treatment regulations. Water Resources The project site is located within the Cape Fear River Basin. Hood Creek serves as the western boundary of the parcel and receives runoff from the entire site. Additionally, there is an unnamed tributary to Hood Creek located near the northern boundary of the parcel. All runoff ultimately leaves the site via Hood Creek near the northwestern corner of the parcel. A wetland is located near the northeastern boundary of the site. This wetland was delineated by Harvey Clifton of Coastal Environmental Consulting, Inc. as a 404 jurisdictional wetland and subsequently confirmed by Teresa E. Russell, the Corps Regulatory Official. The construction limits for this project are located entirely outside the wetland boundary. Although surface water associated with Hood Creek and the unnamed tributary are contained within the Northwest Water Treatment Plant parcel, the stream boundaries were not delineated for the purpose of defining the total project area, since they are located a substantial distance away from the construction area and are not expected to have a substantial impact on the impervious percentage of the project. Similarly, stormwater calculations were confined to the parcel boundaries. Off -site drainage consists of the entire watershed for Hood Creek. All drainage that flows through the currently proposed development area is contained within the parcel boundary. Existing Stormwater Conveyance and Treatment Runoff from all parking and roadway surfaces is collected by catch basins and conveyed by a storm sewer system. The storm sewer discharges onto a rip rap apron and is subsequently conveyed via overland flow to Hood Creek. Runoff from the area north of the main parking and driveway area is conveyed primarily by overland flow and vegetative channels. Proposed Stormwater Conveyance and Treatment Because the site is characterized as low -density development, based upon the impervious percentage of the parcel, and localized areas of high density do not directly discharge to surface waters, no structural stormwater BMPs are being proposed for this site. Following development, the site will consist of 2.4% impervious surfaces. Runoff will be conveyed as vegetated surface flow through much of the site, maximizing opportunities for infiltration and minimizing runoff volumes. Runoff from the proposed 1,800 ft2 chemical storage building and associated driveway and sidewalk will be collected by the existing storm sewer system (Figure 1). Due to the configuration of the existing site and associated constraints, there is no room available for stormwater treatment or vegetated conveyance measures for runoff from these surfaces. Hydraulic calculations indicate that the storm sewer system is adequately sized to convey increased flow from these areas and their incorporation is not expected to result in the degradation of existing stormwater treatment.�� Runoff from the proposed 51,100 ftZ clearwell and 1,000 ftZ metering vault will be conveyed via overland sheet flow and vegetative stormwater conveyance channels. Due to existing slopes and ground cover conditions surrounding the proposed clearwell, allowing runoff from the entire clearwell to freely drain as sheet flow is expected to result in the formation of channelized flow on steep slopes and cause erosion. To address this issue, vegetated channels have been incorporated to convey the runoff from much of the clearwell as overland flow in a controlled manner to a level spreader. In order to maintain non -erosive flows into the wetland, a level spreader will be installed east of the proposed clearwell (Figure 1; C12). This structure will receive runoff from the majority of the proposed clearwell and will diffuse stormwater flows over a wide area, thereby reducing the flow velocity. Details of this structure are shown on drawing C12. The design of the proposed level spreader differs somewhat from the typical state design guidance, which is oriented towards use of level spreaders in conjunction with riparian buffers or filter strips for water quality treatment. In those situations, the objective is to maximize the surface area of the riparian buffer or filter strip that is in contact with stormwater, in order to encourage infiltration and remove pollutants. In the proposed level spreader for this project, the function of the level spreader is to discharge non -erosive flows into the wetland. Calculations for the 10-year storm based on weir flow and channel hydraulic methodologies indicate flow velocities into the wetland will be less than 2 ft/s. In addition to stormwater conveyance measures, temporary measures shall be implemented during construction to limit erosion and control sediment in accordance with the North Carolina Erosion and Sediment Control Planning and Design Manual. M Conclusions The proposed design is for the incorporation of an additional 1.28 acres of impervious area for the Northwest Water Treatment Plant improvement project. The site is characterized as a low - density development due to the low percentage of impervious area and lack of direct stormwater discharge into surface waters. Vegetative conveyance has been incorporated to the maximum extent practical and a velocity dissipation structure is proposed to minimize the velocity of water flowing into the wetland. Based on these characteristics, the proposed development is expected to satisfy all NCDENR DWQ requirements. 0 V) c L ca CL 3 0 L a� c� 3 E L 0 L ca 0 Q. E 0 3 N Z a� O ii aymf.Ie,.+ } , SAE01aWi7aCAN00.FA IELAKDQUAURAGEU.S.WWAROMOFTHEWMUA U.S.i$OLOOMSUWAY ; NORM cnnourbOWnamcnaorra a. orwtaMoFMTAwnHTkaALRg aasrlrmssFm�staarefauSrmeT Vol � - afsae• , e.i lslnfs xa�r _ } - - �,•. - � - to • � ' 3i PROJECT •''�+. „1 1 ®�i P. Ir � 'MATF. rMfF MNU u5: - ' � "U,'T -.:�:" �^• .. i'� r=rt'.e. rat �i ' � j � �s•,> , i. Fes. . � '� Az 1;•' .far. It ♦ 1� —=`�,.a"p _ "too, aaii r1�f.Y•a lait M&1%�� SG4�131tlMb W 'Ri RfYaRit'.MCiI � dOtYMllpltf0lL r�1�a.1�-�� LW�+r s.L rfw �.�la'•Nfa✓•e•.. �r wLrw/ry.rraf»Y.NawfrMw vSaagrAw.. � u' ftr.aa+affry. _ :bcvf..7.i'1r.•,.Ynt^•ti>FNL]]n1 - 3R_.pt=+R ­ii54 -a—.,V -V n,[9,Y.weEiu ltee.�Ndhi`a I+R?aY9, P�Ye[Isd.+l '�•9eyc '°� NAy@Ax+O atnafw3m,re.WA,Rq>ns+ UNt!<N:�x^itn'wntlknG � d.11p1/Mt90fIKWI1GYOn11A W llN v Y&G. cH+'NFYMeAAa?.,�fsV+'6"�'Ne IY §� aNSRYCOeeCN(nONIDY!iIt11NN! 1 A ! flw aw«ama. al�arffowaonl.w�rr .nred.'""""'+rurw.iw .�m.xwrror�.rfumv .r wN IY ra.IN�IMIN►M WVfOO Nf29Mf.1fwlNAfNRrNFYRrwfMr f Y , ,(.�r..ar o IfAYOOM w,iw,JaMNWNwW I.BAm. NC ,W 1r�a�•ffaaNVrW� lNNW1AVW4111NlFNtW.JI.tiI1ALYf11MiaNi f 14 .�OUM L�7 -•.a'-' NObM4llLw.1GB01NOtdLW6/RC►.4. EOf9�►EP.MbP.'OIGNOY4IY w�Nw w�'ir.r�.rrNr.�r `�9' c� afnase�awoNwOowoa.wrwNrsnNsslrw+saxtrpor N.wa•xtwr..fwr. �wen.Nrrrswv '�'p•` Soil Map —Brunswick County, North Carolina m 34' 19 39' p 34° IT 46' tea. `,7 r. •'S is ♦ 1 I IL o Map Scale: 1.7,750 W printed on Aslze {8.5" x 11'j sheet i� n N Meters 0 50 100 2nO 302 Feet 0 250 500 1,000 1,500 USDA Natural Resources Web Soil Survey Conservation Service National Cooperative Soil Survey tl� �i 34° 18' 38" to ro 10/29/2009 Page 1 of 3 34° 17' 45" m c 0 m U r Z c 0 0 U U c P C� C .O 0 C� C O Z Ca C Z W 0 W J ft O. w ° C E w N O W tm 3 ^ m o E ai B-mo (A w � m L 00 — Y N O Q .y m m c� %w U N Uap d O 0) 0i, z oN c`iE� C O_�Z Q Z� p G1 = 2 LD E moz U y.�C-j O N o C�t16��� O Q ��� OLL to m 7 c y t Uc o n ui m° nd o OL E o u c o. yQ E� m CO O E y D J m 'O 7 of m a1 a L a)c N cc!a m z� W E /0 W O�cm o a E r° >�.� � t °�2 � 2a 0am=o ��rLD m m UQ -0o a U) Eaoia mFao w9t) � w8 o F 8 g'S aL n w c g a W ° U 3 t N N A 47 ca _� Tii ca 7 C d y N 7� L OC O J LLCL a S a N R 4 t o 1 d 3 S a o o w+ == a O LU C o $ S 3 to a a k— Q ° o m 'c p y y P o o m Q m a 3 C, a A i a v co a� d c n '` c e o m c m o .� m m c a o m¢ w a m m L) c� c9 c� `9 ���� a oc w m� 5 Ta )C +► 5{ > + a❑yL h m a cmi Soil Map —Brunswick County, North Carolina Map Unit Legend Brunswick County, North Carolina (NC019) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI BaB Baymeade fine sand, 1 to 6 percent slopes 142.7 43.9% BDC Baymeade and Manryn soiis, 6 to 12 percent slopes 48.2 14.8% BnB Blanton fine sand, 0 to 5 percent slopes 73.2 22.5% KrB Kureb fine sand, 1 to 8 percent slopes 1.7 0.5% Lo Leon fine sand 8.0 2.4% Mk Muckalee loam 51.3 15.8% Totals for Area of Interest 326.2 100.0% U_ SDA Natural Resources Web Soil Survey 10129/2009 � Conservation Service National Cooperative Soil Survey Page 3 of 3 Parcel Drainage Description Project Name: Northwest Water Treatment Plant Improvements Project Number: 30094-005 Description: Existing and proposed surface cover for parcel Date:12/4/09 Designed by: MPJ Checked by: EHK Area Summary acres ftZ Total Parcel Area New impervious28 E200 Existing Impervious 3.38 Total Impervious 4.66 Open Tanks 1.86 • Impervious 3.3% % Impervious 2.4% Pre-Dev Forested 179.25 Post-Dev Forested 177.70 New Impervious Buildings ftZ Clearwell No. 1 51071 Chemical and Meter Vault 1025 Chemical Storage Building 2 1800 Sidewalk ftZ Chemical Storage Sidewalk 597 Roadway ftz Chemical Storage Driveway 693 Chemical Storage Parking 643 Existing Impervious Buildings ftZ Clearwell No. 2 31468 Control Bldg and Chemical Rooms 8557 Chemical Storage Building 1 2009 Closed Tank 348 Closed Tank 213 Polymer Building 465 Maintenance Building 1547 Cell Phone Tower 147 Sludge Pumps 393 Sludge Loading Areal 1628 Recycle Pumpsl 260 Pavement ftZ Driveways and Parking 97683 Gravel Parking 787 Gravel Container Storage 405 Sidewalk 1216 Open Tanks/Pits ftZ Clarifiers 24352 Chemical Spill Holding Lagoon 4744 Sludge Equalization Basin 32501 Western Sludge Drying Bed 6751 Eastern Sludge Drying Bed 6620 Sludge Thickener 6071 8712000 55829 147126 202955 81039 * Includes open tanks * Excludes open tanks Hydrograph Report 1 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2008 by Autodesk, Inc. v6.051 Hyd. No. 1 Parcel Drainage Pre -Development Hydrograph type =.. SCS Runoff Storm frequency = 1 yrs Time interval = 2 mM' Drainage area = 198.140 ac Basin Slope = 0.5 % Tc method = KIRPICH Total precip. = 3.63 in Storm duration = 24 hrs * Composite (Area/CN) = [(179.250 x 25) + (15.510 x 39) + (3.380 x 98)] / 198.140 Q (cfs) 0.10 0.09 0.08 Mob 0.05 0.04 0.03 0.02 0.01 0.00 0 Tuesday, Dec 8, 2009 Peak discharge = 0.000 cfs Time to peak = n/a Hyd. volume = 0 cuft Curve number = 27* Hydraulic length = 5000 ft Time of conc. (Tc) = 42.29 min Distribution = Type III Shape factor = 484 Parcel drainage Pre -Development Hyd. No. 1 --1 Year 20 40 60 80 100 Hyd No. 1 Q (cfs) 0.10 0.09 XOD] 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 120 Time (min) �Hydtograph Report 2 Hydraflow Hydrographs Extension for AutoCAD® Civil 3139 2008 by Autodesk, Inc. v6.051 Hyd. No. 1 Parcel Drainage Pre -Development Hydrograph type = SCS Runoff Storm frequency = 10 yrs Time interval = 2 min Drainage area = 198.140 ac Basin Slope = 0.5 % Tc method = KIRPICH Total precip. = 6.83 in Storm duration = 24 hrs * Composite (Area/CN) = [(179.250 x 25) + (15.510 x 39) + (3.380 x 98)] / 198.140 1.00 M Tuesday, Dec 8, 2009 Peak discharge = 1.693 cfs Time to peak = 966 min Hyd. volume = 51,638 cuft Curve number = 27* Hydraulic length = 5000 ft Time of conc. (Tc) = 42.29 min Distribution = Type III Shape factor = 484 Parcel Drainage Pre -Development Hyd. No. 1 -- 10 Year 120 240 360 480 600 720 840 960 Hyd No. 1 Q (cfs) 2.00 1.00 0.00 1080 1200 1320 1440 1560 Time (min) Hydrograph Report 1 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2008 by Autodesk, Inc. v6.051 Hyd. No. 2 Parcel Drainage Post -Development Hydrograph type = SCS Runoff Storm frequency = 1 yrs Time interval = 2 min Drainage area = 198.140 ac Basin Slope = 0.5 % Tc method = KIRPICH Total precip. = 3.63 in Storm duration = 24 hrs Composite (Area/CN) = [(177.700 x 25) + (15.780 x 39) + (4.660 x 98)] / 198.140 Q (cfs) 0.10 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 Tuesday, Dec 8, 2009 Peak discharge = 0.000 cfs Time to peak = n/a Hyd. volume = 0 cuft Curve number = 28* Hydraulic length = 5000 ft Time of conc. (Tc) = 42.29 min Distribution = Type III Shape factor = 484 Parcel Drainage Post -Development Hyd. No. 2 --1 Year 20 40 60 80 100 Hyd No. 2 Q (cfs) 0.10 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 120 Time (min) Hl drograph Report 2 Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2008 by Autodesk, Inc. v6.051 Hyd. No. 2 Parcel Drainage Post -Development Hydrograph type = SCS Runoff Storm frequency = 10 yrs Time interval = 2 min Drainage area = 198.140 ac Basin Slope = 0.5 % Tc method = KIRPICH Total precip. = 6.83 in Storm duration = 24 hrs * Composite (Area/CN) = [(177.700 x 25) + (15.780 x 39) + (4.660 x 98)] / 198.140 Q (cfs) 3.00 2.00 1.00 Tuesday, Dec 8, 2009 Peak discharge = 2.656 cfs Time to peak = 940 min Hyd. volume = 75,433 cuft Curve number = 28* Hydraulic length = 5000 ft Time of conc. (Tc) = 42.29 min Distribution = Type III Shape factor = 484 Parcel Drainage Post -Development Hyd. No. 2 --10 Year 120 240 360 480 600 720 840 960 Hyd No. 2 Q (cfs) 3.00 46 1.00 0.00 1080 1200 1320 1440 1560 Time (min) -k AW s 0 m E w a w r 0 Z A m i 0 Cqq L 'LG6 E E ca 3 ca E L cn 0 o 0 0 0 0 0 �d C O. m o m c m c m c m c m c m c '~ U U C7 U U U U N O C.N- G— Z UJ N cn v O O n Qj m ❑ C C7 C LO m m co v m rn V fq N N 10 f6 f6 ui O O C C c C C O O C7 J i 3 Ln LD N co N M v Go CA W G_ r- O J 3 C (' C CM Cl) O Lq O fl� N O CO In CO C7 N N 01 E W c o e O J W ` n � n coo c�0 Ci v atOR C7 C7 C� - O Oi O C� W co V CD Go O coo M co C W .. cn cn WC G G1 CID GD 1n N o7 M In > J ' 07 q 1n q CO CM M W C W - 6 Go 01 0 h P� f- C7 m Cl It IV It IV In... 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Ili6 M N O O E w O. i O f M K N K N 7 Z CO N C3 C O C9 d Lo LQ N N ti q � O d v c; d� M COD OOD• O OR M OD 7 C G1 " " CD m - M m I- r W M M It v v v v v Cy N cli m It N O] m m M N N N w C C C C C O O O J > W o (nO• OOD• le fN0 � It rn GI N W !� x 0 9 d d > a� M N L ` O O CD Cl O CD Cl C) a _L G! OO c~o N rmi C9 r,� m N EIt 'gr C7 N a- - - - O) f C E r-- CD M N M V N Lo tD OD v N U Ca uri �D ui cci � � •- � CV CV N N - - - O , a a J co cLq ti O Lq M It ONE L C Z 4S R co C U > a1 O CA co CA co V1 u) Cn N m M M U) M Lo O1 C J Cm ID `•' v m ■o Cn 0 Ih ti ti •� t a � v cQO v N o n 0 a N col ccl m m Go ■ U ..r M M Cl) M Cl) — — � - L iri N d C N M V O m f-- OD O Z O Z J d ' m oe r m 1 0 V. O d c � o - N c 'm w oc rn . o co O j m N LP U 'O Ql 0- U co m 3 H qw m=J Oa) N= G — IC'_11 �— m m m N CIn G m�yE cW 8 3 •€0a �o m m c d ~ c apmvi O Lu 2 = 2 w =WCL or w a) a) T a O �� a m N o — cmE E NC mO E + N d) y 7= IM cJ N.6 J = y c O U N y co N .M _ m Ln m C .m = c gEL�.s :: n=-. o w A\ L c COLm N c w (� c m '3G � =m. m co g -- _ as ; M, nN C m w v or a m rn y m c O O M cco 3a o8=m .n EO >+ L c a'0 $ oEk-a o a mc c to !o = C N LO U)O C� axi n C J y N � 0 V m C d ■� A -A •N 3 m OE = m E O_ > 'or U n— 0 � E m m 0 _3 to m U•C C% Lu 2 O c O a O 'OL m N c C m m = 7PrmmC j; c CL CL CL o :5 m ay 06 mn3 CL a E y 85 m m a -- m am «w m E i" m m° 1 `® ) 8 1a0 C CC CU N�fl ai NCIL mC NO m 3 a W �' c E MD 3 b c E m D z° d0 O m - N v 2: � o cm 3v om 3m wN O 9U n o a 0o? o ac c c a E f6 Z o c o m a m w m ® E m• O OON O m O >+ am ai G . O 0 O 4)chi L d as > N o m m m c m m m i m m o > m o m _ m = O m = m m = 2= m = ~ _ ~ ` _ lil _ H U = II.- m W H U H j M v LID w I,- ao CD r r 0 U O U O U O U 0 U O U O U O U O U O U 0 U 0 U O U O U O U O U O U 0 U 1 N N U CU i POINT PRECIPITATION FREQUENCY ESTIMATES FROM NOAA ATLAS 14 w, North Carolina 34302900 N 78.107108 W 49 feet from "Precipitation -Frequency Atlas of the United States" NOAA Atlas 14, Volume 2, Version 3 G.K Bonin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland, 2004 Fxiraoted: Mon, Sep 14 2009 Confidence Limits _ l�_ Seasonality yj` Location Maps Other Info lj GIS data Maps ; Docs i' R Precipitation Intensity Estimates Qn/hr) ARI*60 (years) Fgn7FT1 min min min min 120 amain 3 fir 6 fir 12 24 fir 48 fir 4 d�a 7 da 10 1� 20 1a 30 liter 45 da 60 der = 6.05 4.83 4.02 2.76 1.72 1.02 0.73 0.45 0.26 0.15 0.09 0.05 0.03 0.03 0.02 0.01 0.01 0.01 7.19 EHJ 4.82 3.33 2.09 1.24 0.89 0.54 0.32 0.18 0.11 0.06 0.04 OA3 0.02 0.02 0.01 0.01 0 8.40 6.73 5.67 4.03 2.58 1.5E 1.13 0.70 0.41 0.24 0.14 O O8 OAS 0.04 0.03 0.02 0.02 0.01 10 9.35 7.47 6.30 4.5E 2.97 1.86 1.34 0.83 0.49 0.28 0.16 0.09 0.06 0.04 0.03 0.02 0.02 0.02 25 10.55 8.40 7.10 5.26 3.50 2.26 1.65 1.02 0.61 0.36 0.20 0.1E 0.07 0.05 0.03 0.03 0.02 0.02 50 11.45 9.12 7.70 5.80 3.93 2.60 1.92 1.19 0.71 0.42 0.24 0.13 0.08 0.06 0.04 0.0E 0.02 0.02 100 12.38 9.83 8.29 6.35 4.37 2.97 2.22 1.38 0.83 0.50 0.28 0.15 0.09 0.07 0.04 0.03 0.03 0.02 200 13.30 10.54 8.86 6.90 4.84 3.37 2.55 1.59 0.97 0.58 0.32 0.17 0.10 0.08 0.05 0.04 0.03 0.02 F5-0-0-1 14.50 11.47 9.62 7.65 5.49 3.96 3.05 1.92 1.17 0.71 0.39 0.20 0.12 0.09 0-- 0.04 0.03 0.03 1000 15.48 12.19 10.20 8.26 6.03 4.47 3.49 2.20 1.35 0.83 0.45 0.23 0.14 0.10 0.06 0.04 0.04 0.03 * These precipitation frequency estimates are based on a partial duration series. ARI is the Average Recurrence Interval. Please refer to NOAA Atlas 14 Documerd far more information. NOTE: Formatting forces estimates near zero to appear as zero. * Upper bound of PrecipitatFion ARI**[:5�]F-10-�[15 30 60 120 3 min min min min min fir the 90% confidence interval Intensity Estimates (in/hr) 6 12 24 48 4 7 10 20 30 4560(years) fir hr hr hr day day day 11 day day 11 day 11 day 6.54 5.22 4.35 2.98 1.86 1.11 0.80 0.49 0.29 0.17 0.10 O.OS 0.04 0.03 0.02 0.02 0.01 0.01 0 7.76 6.21 5.20 3.59 2.25 1.36 0.97 0.60 F6-351 0.20 0.12 0.07 0.04 0.03 0.02 0.02 0.02 0.01 9:07 7.26 6.12 4.35 2.79 1.73 1.24 D.77 0.45 0.26 0.15 0.08 0.05 0.04 0.0 OO 02 0.02 0.02 10 10.08 8.06 6.80 4.93 3.2E 2.03 1.47 0.91 0.54 0.32 0.18 0.10 0.06 0.05 .03 0.02 0.02 0.02 25 11.35 9.05 7.64 5.66 3.77 2.47 1.81 1.12 0.67 0.40 0.2- 0.12 1 0.08 0.06 I 0.04 gfl 0.02 OA2 50 12.34 9.82 8.29 6.24 4.23 2.83 2.10 1.31 0.79 0.47 0.27 0.14 0.09 0.07 0.04 0.03 0.03 0.02 100 13.33 10.60 8.93 6.84 4.71 3.24 2.43 1.51 0.92 0.55 0.31 0.16 0.10 0.08 0.05 0.04 0.03 0.02 200 14.33 11.36 9.55 7.44 5.21 3.67 2.78 1.74 1.06 0.65 0.36 0.19 0.12 0.09 0.05 0.04 0.03 0.03 500 15.66 12.39 10.40 8.27 5.93 4.32 3.33 2.10 1.29 0.79 0.44 0.23 0.14 0.10 O 06 0.04 0.03 0.03 1000 16.75 13.19 11.04 8.94 6.53 4.88 3.81 2.41 1.49 0.93 0.51 0.26 0.15 0.11 0.07 0.05 0.04 0.03 The upper bound of the confidence interval at 90% confidence level is the value which 5%of the simulated quantile values for a given frequency are greater than. "These precipitation frequency estimates are based on a partial duration series. ARI is the Average Recurrence Interval. Please refer to NOAA Atlas 14 Documentfor more information. NOTE: Formatting prevents estimates near zero to appear as zero. * Lower bound of the 90% confidence interval Precipitation Intensity Estimates (in/hr) A55** 5 X1? 15 30 60 gl�0 3 6 12 24 48 4710 ZO3045 60(years) min min min min n fir fir fir fir hr day day day day day da day = EKJ Ejj 3.74 2.56 1.60 Ej 0.67 0.41 0.24 0.14 0.08 0FO 57 0.03 0.02 0.02 0.01 F TQ 0.01 0 6.67 5.33 4.47 3.09 1.94 1.15 0.81 0.50 0.29 0.17 0.10 0.06 0.04 0.03 0.02 0.02 0.01 0.01 7.79 6.23 5.26 3.73 2.39 1.46 1.04 0.64 0.37 0.22 0.13 0.07 0.05 0.04 0.02 0.02 0.02 0.01 10 8.64 6.91 5.82 4.22 2.75 1.71 1.23 0.75 0.44 0.26 0.15 0.08 0.05 0.04 0.03 0.02 0.02 0.02 F257 9.70 7.73 6.53 4.84 3.22 2.06 1.50 0.93 0.54 0.32 0.18 0.10 0.06 0.05 0.03 0.03 0.02 0.02 50 10.49 8.35 7.05 5.31 3.60 2.36 1.74 1.07 0.63 0.38 0.21 0.11 0.07 0.06 0.04 0.03 0.02 0.02 100 1 11.27 8.96 7.55 5.78 3.98 2.68 1.99 1.23 0.73 0.44 0.25 0.13 0.08 0.06 0.04 0.03 0.02 0.02 200 12.02 9.53 8.02 6.24 4.38 3.02 2.27 1.41 0.84 0.50 0.28 0.15 0.09 0.07 0.04 0.03 0.03 0.02 500 12.98 10.27 8.62 6.86 4.92 3= 2. 88 ,11 67 1.01 0.60 0.33 0.17 0.11 0.08 0.05 0.04 0.03 0. 22 1000 13.75 10.83 9.06 7.34 5.36 3.93 3.02 1.89 1.E5 0.69 0.38 0.19 0.12 0`09 0.05 0.04 0.03 0.03 'The tower bound of the confidence interval at 90% confidence level is the value which 5%of the simulated auanfile values fora aiven teauencv are less than. aturn to State Mapjs�,j "These precipitation frequency estimates are based on a partial duration maldma series. ARI is the Average Recurrence Interval. Please refer to NOAA Atlas 14 Document for more information. NOTE: Formatting prevents estimates near zero to appear as zero. Text version of tables� Partial duration based Point IDF Curves - Version: 3 34.302900 M 78.107108 W 49 ft 10 7 L s 2 •• 1 31 0.7 „ 0.3 Y 0.2 .. 1 .07 .05 +' .03 +e. .02 .01 0 0 L o. Al-.a_ -'_ - J z-- T — 7-- ii .001 G G G G G G 2 L L L L L L L L L 31 31 31 31 31 31 31 3. :0 ! •i 6 / I I I I ! I I E m I N S S I I r7 i S t S S S I I I I I rp m N m Y S S I I .b m a m e a a a I I I A 9 I e 'O I e M � '6 I I a a I a M '6 -� I 1 n m n m m m .. .+ a cn a 0 It in h m In m m In m to �o a Duration -• -• a Cl) a m Mon Sep 14 15s05813 2009 Maps - Average Reourrenoe Interval (wears) 2-year t 100-year — -, ar, -§-- 200-year -e,- 10-year -e- 500-year -+- 25- ear ems- 1000- ear -e- r ; 170"'W 110-W 100"'W q0"'W i90"'W z r � t 70"W These maps were produced using a direct map request from the U.S. Census Bureau Mapoino and Cartographic Resources Tiler Map Server. Please read disclai for more information. I 111'0 d ZJ; - State — Connector County Stream Indian Resv Military Area Lake/Pond/Ocean National Park Street Other Park — Expressway City Highway o Z--sCqunty6 s Scale 1: 22i15bs 22 f1 *average —true scale depentls on Monitor$ esoloution Other Maps/Photographs - View USGS digital ortho hp oto quadrangle (IDOQ) covering this location from TelraServer; USGS Aerial Photograph may also be available from this site. A DOQ is a computer -generated image of an aerial photograph in which image displacement caused by terrain relief and camera tilts has been removed. It combines the image characteristics of a photograph with the geometric qualities of a map. Visit the USGS for more information. Watershed/Stream Flow Information - Find the Watershed for this location using the U.S. Environmental Protection Agency's site. Climate Data Sources - Precipitation frequency results are based on data from a variety ofsources, but largely NCDC. The.following links provide general information about observing sites in the area, regardless of if their data was used in this study. For detailed information about the stations used in this study, please refer to NOAA Atlas 14 Document. Using the National Climatic Data Center's (NCDC? station search engine, locate other climate stations within: +50 minutes ...OR.. f +/-1 degree of this location (34.302900/-78.107108). Digital ASCII data can be obtained directly from N D Hydrometeorological Design Studies Center DOC/NOAA/National Weather Serviee 1325 East-West Highway Saver Spring, MD 20910 (301)713-1669 Questions?:T�rtaaaeov Disclaimer Northwest WTP Stormwater Channel H&S Project No.: 30994 Date: 11/30/09 Calculated by: MPJ Checked by: EHK Objective: Determine channel dimensions required for non -erosive velocities Location: East of proposed clearwell Post-Develooment Channel Total 19658 ft2 1 0.45 Jacre Impervious 15332 ft2 1 0.35 lacre Pervious 4326 ft2 0.10 1 acre % Impervious 78% in/hr 1 cfs Avg. C 0.78 10-Tr 5-min Rainfall Int. 9.35 Peak Q 3.29 Normal Depth Procedure (Adapted from Malcom's Elements of Urban Stormwater Designl Q (cfs) 3.29 n 0.03 Slope (ft/ft) 0.085 Zreq 0.2 0.0 Depth (ft) 0.26 Bottom Width (ft) 2 Side Slope (ft:ft) 4 Area (ft2) Wetted Perimeter (ft) Hyd. Radius (ft) Zav Velocity (ft/s) Shear Stress (lb/ft2) Temporary Liner: Straw with Net Allowable Shear Stress (Ib/ft2) 1.45 Estimate or use solver to balance Zreq and Zav Northwest WTP Stormwater Velocity Dissipater H&S Project No.: 30994 Date:11/24/09 Calculated by: MPJ Checked by: EHK Milestone: Permitting Objective: Determine peak flow draining to velocity dissipation structure and determine 10-yr flow velocity over structure Time of Concentration * 5 minute Tc used for all calculations, since Tc for longest flow path is < 5 minutes Rainfall Intensities 1-yr 6.05 in/hr 2-yr 7.19 in/hr 5-yr 8.4 in/hr 10-yr 9.35 in/hr 25-yr 10.55 in/hr 50-yr 11.45 in/hr 100-yr 12.38 in/hr Obtained from NOAA ATLAS 14 using coordinates for site from Google Earth Total 81600 ft2 11.87 1 acre Impervious 30474 ft2 0.70 acre Pervious 51126 ft2 11.171acre % Impervious 37% 0.56 Peak Flows Avg. C Rational Method 1-yr 6.29 cfs 2-yrl 7.48 1 cfs 5-yrl 8.74 1 cfs 10-yr 9.73 cfs 25-yr 10.98 cfs 50-yr 11.91 cfs 100-yr 12.88 cfs 10-vr flow over dissipation structure 10-yr Flow 9.7 cfs Cw 3 Length 40 ft Head 0.19 ft Velocity 1.3 ft/s Northwest WTP Stormwater Channel H&S Project No.: 30994 Date:12/17/09 Calculated bv: MPJ Checked by: EHK Objective: Determine channel dimensions required for non -erosive velocities Location: Downstream of proposed velocity dissipater Post -Development Channel Total 81600 ft' 1 1.87 Jacre Impervious 30474 ftZ 0.70 lacre Pervious 51126 ft2 1.17 Jacre % Impervious 37% hr Avg. C 0.43 10-yr 5-min Rainfall Int. 9.35 1cfs Peak Q 7.53 Normal Depth Procedure (Adapted from Malcom's Elements of Urban Stormwater Design) Q (cfs) 7.53 n 0.04 Slope (ft/ft) 0.02 Zreq 1.4--- 0.0 Depth (ft) 0.14 Bottom Width (ft) 40 Side Slope (ft:ft) 4 Area (ft') 5.49 Wetted Perimeter (ft) 41.12 Hyd. Radius (ft) 0.13 Zav 1.4' �' Velocity (ft/s) 1.37 Estimate or use solver to balance Zreq and Zav co 0 m to Lj I M W DELINEATION SITE L/MI UDGE PIT [-nrjs•36'43"W 282.88' SITE AREAS: BLDG TOTAL PARCEL AREA: 2001 AC. TOTAL DELINEATION SITE AREA: 13.67f AC. 404 WETLAND AREA 1: 0.98f AC LEGEND 404 WETLAND AREA xi 404 WETLAND FLAG (FTDS = TIE TO DELINEATION SITE) STORM DRAIN PIPE 000 (CPP = CORRUGATED PLASTIC o RCP = REINFORCED CONCRETE) z z GRAPHIC SCALE u 0 50 100 N88'00'35"W z 102.39' CL V) 1 inch = 100 ft. . . . EX. REBAR N: 203308. 6 Y NCO. � E: 2269898.78 00 � 0800 ,! S86'36'50"E 2 4 I 780.�94' TTDi12S2 1 0 - TTD C PIT oN84 27 ... ..� 45 21 .'.•... _ . . . . . 44 22 ... 43 23 .. •.' - . 42 .- 404 WETLAND . 41N AREA 1 TOTAL AREA 24 WITHIN DELINEATION SITE LIMITS 40 �6• /5--. 0.98# AC. 39 38 30 29 3t .... . 28 32 . ' ' ' '• 37N 33 36 135 ^ 1 CLEAR WELL 2 �. T DR ItfWAY N87'17'38"W- i�;9u �a- BLDG EX. REBAR N: 203359.82 / NE: 2270218.75 I h N: 203211.64 E: 2 i 70165.92 '.'% C A I I IT77� ti [ Q fn 203000 � Z O _Z lz Y W o Ljj Co 7 W �l WETLAND FLAG COORDINATE TABLE FLAG NORTHING EASTING TTDS1 203232.63 2269811.22 20 203217.42 2269830.77 21 203142.01 2269845.64 22 203091.05 2269851.08 23 203019.94 2269859.92 24 202922.92 2269870.01 25 202882.05 2269829.30 26 202867.57 2269818.62 .27 202838.15 2269791.64 28 202823.56 2269804.85 29 202833.03 2269834.16 30 202851.26 2269895.80 31 202826.50 2269913.74 32 202811.43 2269915.97 33 202784.32 2269909.51 34 202757.86 2269938.34 35 202772.16 2269944.21 36 202801.84 2269956.27 37N 202802.29 2269986.83 38 1 202550.73 2269970.24 39 202877.11 2269978.62 40 202907.64 2269990.00 41N 202971.96 2269988.11 42 203009.59 2269940.03 4 1 203053.43 2259922.48 44 20J116.24 2269929.98 45 203168.93 2269908.68 TTD52 1 203226.80' 2269909.70 A426 0 a- �Ln SR 1 ~-DELINEATION SITE PARCEL SQL RR VICINITY MAP (NTS) GENERAL NOTES: 1. THIS IS A CLEAN WATER ACT, • SECTION 404 JURISDICTIONAL (404) MAP THIS IS NOT A BOUNDARY SURVEY. PARCEL BOUNDARY SHOWN PER BRUNSWICK COUNTY TAX DATA. 2. 404 DELINEATION SITE DOES NOT REPRESENT AN EXISTING PARCEL BOUNDARY. IT IS A PORTION OF BRUNSWICK COUNTY PINT1-047-05. (OWNER: N/F - SIMPKINS, AGNES FRANKS; DB: 413, PG: 347). 3. 404 AREAS DELINEATED BY COASTAL ENVIRONMENTAL CONSULTING (910-791-6411) AND FIELD SURVEYED BY WITHERS & RAVENEL USING A TOTAL STATION SURVEY INSTRUMENT CAPABLE OF 0100'07" ACCURACY. 404 WETLANDS DELINEATION CERTIFICATE THIS CERTIFIES THAT THIS COPY OF THIS PLAT ACCURATELY DEPICTS THE BOUNDARY OF THE JURISDICTION OF SECTION 404 OF THE CLEAN WATER ACT WITHIN THE DESIGNATED INSET AREA, AS DETERMINED BY THE UNDERSIGNED ON THIS DATE. OTHER AREAS OF JURISDICTION MAY BE PRESENT ON THE SITE BUT HAVE NOT YET BEEN DELINEATED. UNLESS THERE IS A CHANGE IN THE LAW OR OUR PUBLISHED REGULATIONS, THIS DETERMINATION MAY BE RELIED UPON FOR A PERIOD NOT TO EXCEED FIVE YEARS FROM THIS DATE. THIS DETERMINATION WAS MADE UTILIZING THE 1987 CORPS OF ENGINEERS WETLAND DELINEATION MANUAL. ANY ISOLATED WETLANDS OR WATERS THAT ARE OUT OF CORPS JURISDICTION HAVE BEEN LABELED ON THE SURVEY. -MAWRE, U.S ARMY CORPS OF ENGINEERS OFFICIAL DA TE TI TLE. EXPIRATION DA TE OF DELINEATION: USACE ACTION ID: •.iJ � ' ------ CERTIFICATE OF ACCURACY & MAPPING I, THE UNDERSIGNED. CERTIFY THAT THIS SURVEY WAS DRAWN UNDER MY SUPERVISION AND THAT THIS SURVEY HAS BEEN PREPARED IN ACCORDANC MT14 THE STANDARDS OF WETLAND PLATTING AS ESTABLISHED BY THE U.S. ARMY CORPS OF ENGINEERS, WIINES'S MY ORIGINAL SIGNATURE, LICENSE NUMBER AND SEAL THIS OA Y OF O e-r 200�' MILES 0. Mc ALL, Ill - PROFESSIONAL LAND SURVEYOR L-318) I l F- Z Q J CL w w ne F- tY w F- Ln w F- w C Z c 2 IL Z < � a a r0r-- G V m �n CL S. C) r � v� 0 z 1 of t