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HomeMy WebLinkAboutSW8080653_HISTORICAL FILE_20081119STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW8 0$0\,DG3 DOC TYPE ❑ CURRENT PERMIT ❑ APPROVED PLANS HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE 200Cd\\ \°\ YYYYMMDD NIAT�c Michael r_Caslcy, Governor YWilliam G. Ross Jr., Secretary [— North Carolina Department or Environment and Natural Resources O Y Coleco 11. Sullins Director Division or Water Quality November 19, 2008 Commanding Officer c/o Mr. Carl H. Baker, Deputy Public Works Officer USMCB Camp Lejeune 1005 Michael Road Camp Lejeune, NC 25847 Subject: State Stormwater Management Permit No. SW8 080653 MICAS New River Aircraft Maintenance Hanger (P-526/P-651) High Density Commercial Wet Pond Project County County Dear Mr. Baker: The Wilmington Regional Office received a complete State Stormwater Management Permit Application for MICAS New River Aircraft Maintenance Hanger (P-526/P-651) on November 12, 2008. 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 2006-246 and Title 15A NCAC 2H.1000. We are forwarding Permit No. SW8 080653, dated November 19, 2008, for the construction and operation of the subject project. This permit shall be effective from the date of issuance until November 19, 2018, and shall be subject to the conditions and limitations as specified therein. Please pay special attention to the Operation and Maintenance requirements in this permit. Failure to establish an adequate system for operation and maintenance of the stormwater management system will result in future compliance problems. If any parts, requirements, or limitations contained in this permit are unacceptable, you have the right to request an adjudicatory hearing upon written request within thirty (30) days following receipt of this permit. This request must be in the form of a written petition, conforming to Chapter 150B of the North Carolina General Statutes, and filed with the Office of Administrative Hearings, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such demands are made this permit shall be final and binding. If you have any questions, or need additional information concerning this matter, please contact Christine Nelson, or me at (910) 796-7215. Sincerely, Georgette Scott Stormwater Supervisor Division of Water Quality ENB/can: S:\WQS\STORMWATER\PERMIT\080653.nov08 cc: Onslow County Inspections Christine Nelson r-Wilmington Regional Office Central Files No thcarolina North Carolina Division of Water Quality 127 Cardinal Drive Extension Wilmington, NC 28405 Phone (910) 796-7215 Customer Service Wilmington Regional Office Internet. st tvw.ncw:uenp�lilv.org Fax (910)350-2004 1-877-623-6748 An Equal Opportunity/Affirmative Action Employer — 50% Recycled/10% Post Consumer Paper State Stormwater Management Systems Permit No. SW8 080653 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT HIGH DENSITY COMMERCIAL DEVELOPMENT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO Commanding Officer & Carl Baker, Deputy Public Works Officer & USMCB Camp Lejeune MCAS New River Aircraft Maintenance Hanger (P-526/P-651) Campbell Street, Camp Lejeune, Onslow County FOR THE construction, operation and maintenance of a wet detention pond and filter strip in compliance with the provisions of Session Law 2006-246 and 15A NCAC 2H .1000 (hereafter referred to as the "stormwater rules') and the approved stormwater management plans and specifications and other supporting data as -attached and on file with and approved by the Division of Water Quality and considered a part of this permit. This permit shall be effective from the date of issuance until November 19, 2018, and shall be subject to the following specified conditions and limitations: I. DESIGN STANDARDS This permit is effective only with respect to the nature and volume of stormwater described in the application and other supporting data. 2. This stormwater system has been approved for the management of stormwater runoff as described in Section 1.7 and 1.8 of this permit. The stormwater controls have been designed to handle the runoff from a total of 180,525 square feet of impervious area. 3. The tract will be limited to the amount of built -upon area indicated in Section I and 1.8 on page 3 of this permit, and per approved plans. 4. All stormwater collection and treatment systems must be located in either dedicated common areas or recorded easements. The final plats for the project will be recorded showing all such required easements, in accordance with the approved plans. 5. The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system. 6. The built -upon areas associated with this project shall be located at least 30 feet landward of all perennial and intermittent surface waters. Page 2 of 8 f . State Stormwater Management Systems Permit No. SW8 080653 A 30 foot filter strip has been provided for the 1,731 square feet of built -upon area added to the hanger parking apron and must be maintained at design condition The following design criteria have been provided in the wet detention pond and must be maintained at design condition: a. Drainage Area, acres: 8.43 Onsite, ft : 355726 Offsite, ft2: 11296 b. Total Impervioss Surfaces, ft2: 178,794 Buildings, ft : 73,774 Roads/Parking, ft2: 101,481 Sidewalk & Concrete, ft2: 1,729 Offsite, ft2: 1,810 c. Average Pond Design Depth, feet: 3.08 d. TSS removal efficiency: 90% e. Design Storm: 1.5" f. Basin Bottom Elev., FMSL: 5.0 g. Sediment Cleanout Elev., FMSL: 6.0 h. Permanent Pool Elevation, FMSL: 10.0 i. Permanent Pool Surface Area, ft : 36,797 j. Storage Elevation, FMSL: 1.1.4 k. Permitted Storage Volume, ft3: 58,767 I. Predevelopment 1-yr 24-hr discharge rate, ft3/s: 14.77 m. Controlling Orifice: 2" O pipe n. Post developmer� treatment volume discharge rate, ft s: 0.10 o. Permanent Pool Volume, ft3: 103,290 p. Forebay Volume, ft3: 20,995 q. Maximum Fountain Horsepower: 1/3 r. Receiving Stream / River Basin: New River / White Oak S. Stream Index Number: 19-(15.5) t. Classification of Water Body: "Sc, NSW" II. SCHEDULE OF COMPLIANCE 1. The stormwater management system shall be constructed in its entirety, vegetated and operational for its intended use prior to the construction of any built -upon surface. 2. During construction, erosion shall be kept to a minimum and any eroded areas of the system will be repaired immediately. 3. The permittee shall at all time provide the operation and maintenance necessary to assure the permitted stormwater system functions at optimum efficiency. The approved Operation and Maintenance Plan must be followed in its entirety and maintenance must occur at the scheduled intervals including, but not limited to: a. Semiannual scheduled inspections (every 6 months). b. Sediment removal. C. Mowing and re -vegetation of slopes and the vegetated filter strip. d. Immediate repair of eroded areas. e. Maintenance of all slopes in accordance with approved plans and specifications. f. Debris removal and unclogging of outlet structure, orifice device, level spreader, filter strip, catch basins and piping. Q. Access to the outlet structure must be available at all times. Page 3 of 8 State Stormwater Management Systems Permit No. SW8 080653 4. Records of maintenance activities must be kept for each permitted BMP. The records will indicate the date, activity, name of person performing the work and what actions were taken. Decorative spray fountains will be allowed in the stormwater treatment system, subject to the following criteria: a. The fountain must draw its water from less than 2' below the permanent pool surface. b. Separated units, where the nozzle, pump and intake are connected by tubing, may be used only if they draw water from the surface in the deepest part of the pond. c. The falling water from the fountain must be centered in the pond, away from the shoreline. d. The maximum horsepower for a fountain in this pond is 1/3 horsepower. The permittee shall submit to the Division of Water Quality an annual summary report of the maintenance inspection records for each BMP. The report shall summarize the inspection dates, results of the inspections, and the maintenance work performed at each inspection. Access to the stormwater facilities shall be maintained via appropriate easements at all times. 8. The facilities shall be constructed as shown on the approved plans.. This permit shall become void unless the facilities are constructed in accordance with the conditions of this permit, the approved plans and specifications, and other supporting data. 9. Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to operation of this permitted facility, a certification must be received from an appropriate designer for the system installed certifying that the permitted facility has been installed in accordance with this permit, the approved plans and specifications, and other supporting documentation. Any deviations from the approved plans and specifications must be noted on the Certification. 10. If the stormwater system was used as an Erosion Control device, it must be restored to design condition prior to operation as a stormwater treatment device, and prior to occupancy of the facility. 11. The permittee shall submit to the Director and shall have received approval for revised plans, specifications, and calculations prior to construction, for any modification to the approved plans, including, but not limited to, those listed below: a. Any revision to any item shown on the approved plans, including the stormwater management measures, built -upon area, details, etc. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area or to the drainage area. e. Further subdivision, acquisition, lease or sale of all or part of the project area. The project area is defined as all property owned by the permittee, for which Sedimentation and Erosion Control Plan approval or a CAMA Major permit was sought. f. Filling in, altering, or piping of any vegetative conveyance shown on the approved plan. Page 4 of 8 State Stormwater Management Systems Permit No. SW8 080653 12. The Director may notify the permittee when the permitted site does not meet one or more of the minimum requirements of the permit. Within the time frame specified in the notice, the permittee shall submit a written time schedule to the Director for modifying the site to meet minimum requirements. The permittee shall provide copies of revised plans and certification in writing to the Director that the changes have been made. 13. The permittee shall submit final site layout and grading plans for any permitted future areas shown on the approved plans, prior to construction. 14. A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum of ten years from the date of the completion of construction. III. GENERAL CONDITIONS This permit is not transferable except after notice to and approval by the Director. In the event of a change of ownership, or a name change, the permittee must submit a completed Name/Ownership Change form, to the Division of Water Quality, signed by both parties, and accompanied by supporting documentation as listed on page 2 of the form. The project must be in good standing with the Division. The approval of this request will be considered on its merits and may or may not be approved. 2. The permittee is responsible for compliance with all permit conditions until such time as the Division approves the transfer request. 3. Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to enforcement action by the Division of Water Quality, in accordance with North Carolina General Statute 143-215.6A to 143-215.6C. 4. The issuance of this permit does not preclude the Permittee from complying with any and all statutes, rules, regulations, or ordinances, which may be imposed by other government agencies (local, state, and federal) having jurisdiction. In the event that the facilities fail to perform satisfactorily, including the creation of nuisance conditions, the Permittee shall take immediate corrective action, including those as may be required by this Division, such as the construction of additional or replacement stormwater management systems. 6. The permittee grants DENR Staff permission to enter the property during normal business hours for the purpose of inspecting all components of the permitted stormwater management facility. The permit issued shall continue in force and effect until revoked or terminated. The permit may be modified, revoked and reissued or terminated for cause. The filing of a request for a permit modification, revocation and re -issuance or termination does not stay any permit condition. Unless specified elsewhere, permanent seeding requirements for the stormwater control must follow the guidelines established in the North Carolina Erosion and Sediment Control Planning and Design Manual. Approved plans and specifications for this project are incorporated by reference and are enforceable parts of the permit. Page 5 of 8 State Stormwater Management Systems Permit No. SW8 080653 10. The issuance of this permit does not prohibit the Director from reopening and modifying the permit, revoking and reissuing the permit, or terminating the permit as allowed by the laws, rules and regulations contained in Session Law 2006- 246, Title 15A NCAC 2H.1000, and NCGS 143-215.1 et.al. 11. The permittee shall notify the Division of any name, ownership or mailing address changes at least 30 days prior to making such changes. 12. The permittee shall submit a permit renewal application at least 180 days prior to the expiration date of this permit. The renewal request must include the appropriate documentation and the processing fee. Permit issued this the 191h day of November 2008. CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION Division of Water Quality By Authority of the Environmental Management Commission Page 6 of 8 State Stormwater Management Systems Permit No. SW8 080653 MCAS New River Aircraft Maintenance Hanger (P-526/P-651) Stormwater Permit No. SW8 080653 Onslow County Designer's Certification I, , as a duly registered in the State of North Carolina, having been authorized to observe (periodically/ weekly/ full time) the construction of the project, (Project) for (Project Owner) hereby state that, to the best of my abilities, due care and diligence was used in the observation of the project construction such that the construction was observed to be built within substantial compliance and intent of the approved plans and specifications. The checklist of items on page 2 of this form is included in the Certification. Noted deviations from approved plans and specification: Signature Registration Number Date SEAL Page 7 of 8 . f . State Stormwater Management Systems Permit No. SW8 080653 Certification Requirements: 1. The drainage.area to the system contains approximately the permitted acreage. 2. The drainage area to the system contains no more than the permitted amount of built -upon area. 3. All the built -upon area associated with the project is graded such that the runoff drains to the system. 4. All roof drains are located such that the runoff is directed into the system. 5. The outlet/bypass structure elevations are per the approved plan. 6. The outlet structure is located per the approved plans. 7. Trash rack is provided on the outlet/bypass structure. 8. All slopes are grassed with permanent vegetation. 9. Vegetated slopes are no steeper than 3:1. 10. The inlets are located per the approved plans and do not cause short- circuiting of the system. 11. The permitted amounts of surface area and/or volume have been provided. 12. Required drawdown devices are correctly sized per the approved plans. 13. All required design depths are provided. 14. All required parts of the system are provided, such as a vegetated shelf, and a forebay. 15. The required system dimensions are provided per the approved plans. cc: NCDENR-DWQ Regional Office Onslow County Building Inspections State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM This form may be photocopied for use os on original I. GENERAL INFORMATION 1. Applicants name (specify the name of the corporation, individual, etc, who owns the project): 2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance): 3. Mailing Address for person listed in item 2 above: IW5 Michael Road City:Camo_gjeune State:NC Zip:25847 Phone: (910 ) 451-213 Fax: ( 1 4. Project Name (subdivision, facility, or establishment name -should be consistent with project name on plans, specifications, letters, operation and maintenance agreements, etc.): MCAS New River Aircrak Maintenance Hangar (P-52UP 1) 5. Location of Project (street address): located end of _ : 11 ! _ll St.and :;lil feet . , ..1 at the existingAirfield- ! 1 ,9 1 6. Directions to project (from nearest major intersection): !11 N: �S:!:1t :.1 •. 1':. :.. . _1.1 .:_L: K.' 1 ,I :11..� :1�.• ,, , 1: �1, 7. Latitude:34° 43' 01" N Longitude:770 26' 27" W of project 8. Contact person who can answer questions about the project: Name:Ryan Hambleton. PE Telephone Number: (212 1 %6.4819 Email:RHambletonOStewart-eng com H. PERMIT INFORMATION: FormSWU-101 Version03.27.08 ®C a r= 1 �7 8 � Page I of DD OCT 0 8 �00 DWQ PROJ # NOV 1 2 2008 V1. Specify whether project is (check one): NNew [-]Renewal❑Mication .�—_ 2. If this application is being submitted as the result of a renewal or modification to an existing permit, list the existing permit numberN/A and its issue date (if known) 3. Specify the type of project (check one): ❑Low Density ❑High Density ❑Redevelop ❑General Permit ❑Universal SMP ❑Other 4. Additional Project Requirements (check applicable blanks; information on required state permits can be obtained by contacting the Customer Service Center at 1-877-623-6748): ❑LAMA Major ❑Sedimentation/Erosion Control ❑404/401 Permit ❑NPDES Stormwater III. PROJECT INFORMATION 1. In the space provided below, summarize how stormwater will be treated. Also attach a detailed narrative (one to two pages) describing stormwater management for the project. Stormwater from the site (new parking lot and new hangar) will be 12iped to one wet detention pond for water quality treatment. The captured stormwater will treat the 1.5" storm and will be sized to remove the 90% TSS. 2. Stormwater runoff from this project drains to the White Oak River basin. 3. Total Property Area: N/A acres 4. Total Wetlands Area: 0 acres 5. 100' Wide Strip of Wetland Area: N/A acres (not applicable if no wetlands exist on site) 6. Total Project Area":14.6 acres 7. Project Built Upon Area:41.3 % 8. How many drainage areas does the project have? 2 9. Complete the following information for each drainage area. If there are more than two drainage areas in the project, attach an additional sheet with the information for each area provided in the same format as below. For high density projects, complete the table with one drainage area for each engineered stormwater device. Basin Information Drainage Area 1 Drainage Area 2 Receiving Stream Name New River New River Stream Class &Index No. 19-(15.5) �.3c f t5A 19-(15.5) 5C y Total Drainage Area (so 367,022 sf 8 ,q 3Qc 4,451 sf On -site Drainage Area (so 355,726 sf 4,451 sf Off -site Drainage Area (so 11,296 sf - Existing Impervious" Area (so 91,479 sf - Proposed Impervious"Area (so 178,794 sf 1,731 sf % Impervious` Area (total) 48.7 % 38.9 % Impervious" Surface Area Drainage Area 1 Drainage Area 2 On -site Buildings (so 73,774 sf (jjar t On -site Streets (so 19,332 IAp o L.A,pho On -site Parking (so 82,149 sf 1,731 sf On -site Sidewalks (so 1,579 sf Other on -site (so 150 sf Off -site (so 1,810 sf 10-4fL'A Total (so: 178,794 sf 1,731 sf Fonn SWU-101 Version 03.27.08 Page 2 of 4 finpernious arm is de fined as the built upon area including, but not lindled to, buildings, roads, parking areas, sidelvalks, gravel area's, etc. "'Total project orea shall be calculated fussed oo llte current policy regarding inelusion of roellmnds itt the built upon area percentage calculation. This is the area used to calcubde percent project built upon area (Blbl). 10. How was the off -site impervious area listed above derived?Topographic survey of site IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS One of the following deed restrictions and protective covenants are required to be recorded for all subdivisions, outparcels and future development prior to the sale of any lot. if lot sizes vary significantly, a table listing each lot number, size and the allowable built -upon area for each lot must be provided as an attachment. Forms can be downloaded from http://h2o enr state nc us/su/bmp forme htm - deed restrictions. Form DRPC-1 High Density Commercial Subdivisions Form DRPC-2 High Density Developments with Outparcels Form 13RPC-3 High Density Residential Subdivisions Form DRPC- I Low Density Commercial Subdivisions Form DRPC-5 Low Density Residential Subdivisions Form DR15C-6 Low Density Residential Subdivisions with Curb Outlets By your signature below, you certify that the recorded deed restrictions and protective covenants for this project shall include all the applicable items required in the above form, that the covenants will be binding on all parties and persons claiming under them, that they will run with the land, that the required covenants cannot be changed or deleted without concurrence from the State, and that they will be recorded prior to the sale of any lot. V. SUPPLEMENT FORMS 'rhe applicable state stormwater management permit supplement form(s) listed below must be submitted for each BMP specified for this project. Contact the Stormwater and General Permits Unit at (919) 733.5083 for the status and availability of these forms. Forms can be downloaded from bttp://h2o.enr state nc us/sti/bmp forme htm. Form SW401-Low Density Form SW401-Curb Outlet System Form SW401-Off-Site System Form SW401-Wet Detention Basin Form SW401-Infiltration Basin Form SW401-Infiltration Trench Form SW401-13ioretention Cell Form SW401-1-evel Spreader Form SW401-Wetland Form SW401-Grassed Swale Form SW401-Sand Filler Form SW401-Permeable Pavement Form SWU-101 Version 03 27.08 Low Density Supplement Curb Outlet System Supplement Off -Site System Supplement Wet Detention Basin Supplement Infiltration Basin Supplement Underground Infiltration Trench Supplement Bioretention Cell Supplement Level Spreader/Filter Strip/Restored Riparian Buffer Supplement Constructed Welland Supplement Grassed Swale Supplement Sand Filter Supplement Permeable Pavement Supplement j�E C E I V ED OCT 0 8 2008 DWO Page 3 u1.4 PROJ # i' VI. SUBMITTAL REQUIREMENTS Only complete application packages will be accepted and reviewed by the Division of Water Quality (DWQ). A complete package includes all of the items listed below. The complete application package should be submitted to the appropriate DWQ Office. (Appropriate office may be found by locating project on the interactive online map at hup:f/h2o.enc.stote.nc.us/su/msi mans.hun) 1. Please indicate that you have provided the following required information by initialing in the space.provided next to each item. Initials • Original and one copy of the stormwater Management Permit Application Form VIA/—�� • Original and one copy of the Deed Restrictions & Protective Covenants Form (if_ required as per Part IV above) �, L • Original of the applicable Supplement Forms) and O&M agreement(s) for 13MP /4C7 • Permit application processing fee of $505 (Express: $4,000 for HD, $2,000 for LD) payable to NCDENR • Calculations & detailed narrative description of stormwater treatment/management • Copy of any applicable soils report tot • Two copies of plans and specifications (sealed, signed &dated), including: - Development/Project name - Engineer and firm - Legend - North arrow - Scale - Revision number & date - Mean high water line - Dimensioned property/project boundary - Location map with named streets or NCSR numbers - Original contours, proposed contours, spot elevations, finished floor elevations - Details of roads, drainage features, collection systems, and stormwater control measures - Wetlands delineated, or a note on plans that none exist - Existing drainage (including off -site), drainage easements, pipe sizes, runoff calculations - Drainage areas delineated - Vegetated buffers (where required) VI1. AGENT AUTHORIZATION If you wish to designate authority to another individual or firm so that they may provide information on your behalf, please complete this section. (ex. designing engineer or firm) Designated agent (individual or firm): Siewart l::ngineerinf Ryan Hambleton Mailing Address: 421 Fayetteville St.. Suitc 400 City: Raleigh Statc:NC Zip:_ 27601 Phone. ( 919 1 866-4891 Fax: (919- 1 380-8752 Email: �2ALY" b%'>< M ®S/ac Vlll. APPLICANT'S CERTIFICATION /�J•�/! �� 1, (print or type name of person listed in General h fonaation, itent 2) 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 theapproved plans, that the required deed restrictions and protective covetyn s will be rec d, and that the.proposcd project complies with the requirements of 15A NCAC 2F1.1000. / J n A Date: /a— —06 FonnSWU-101 Version03.27.08 Page 4of4 P. 01 t TRANSACTION REPORT NOV-20-2008 THU 08:10 AM FOR: NCDENR 910 350 2004 SEND DATE START RECEIVER TX TIME PAGES TYPE NOTE M# DP NOV-20 08:08 AM 919104512927 1'47" 9 FAX TX OK 600 TOTAL 1M 47S PAGES: 9 State of North Carolina Department of Environment and Natural Resources Wilmington Regional Office Michael F. Easley, Governor FAX COVER SHEET Date: �� To: 0 2'"r l— Co:�- Fax: Re: `L William G. Ross, Jr., Secretary No. Pages (excl. cover): Express Permitting From: Sa:ndr� a E� xurn Phone: M0296"7265 Fax: 127 Cardinal Drive Extension, Wilmington, NC 29405 • (910) 79&7215 • An Equal opportunity Affirmative Action Employer i I P. 01 TRANSACTION REPORT NOV-20-2008 THU 08:13 AM FOR: NCDENR 910 360 2004 SEND DATE START RECEIVER TX TIME PAGES TYPE NOTE M# DP NOV-20 08:10 AM 919193808752 2'12" 9 FAX TX OK 601 l TOTAL 2M 12S PAGES: 9 State of North Carolina Department of Environment and Natural Resources Wilmington Regional Office Michael F. Earley, Governor FAX COVER SHEET William C. Ross, Jr., Secretary Date:No. Pages (excl. cover): 4 Express Permitting To: r is a itit eL_ From: Sandra Gxum Q Phone (910) 796-7265 Fax: Far: (910) 350-2004_ Re: Hard Copy to follow 127 Cardinal Drive Extension, Wilmington, NC 28405 • (910) 796-7215 • An Equal Opportunity Affirmative Action Employer www.crewere-env.com S ` No, 1 O BY�Sb S T E WA R T November 11, 2008 Christine Nelson Division of Water Quality - Wilmington Regional Office r 127 Cardinal Drive Extension Wilmington, NC 28405 Re: Request for Additional information comments Dear Ms. Nelson Please find below are the comment responses for the request for additional information for Stormwater project No. SW8 056053. 1. Please find 3 copies of the revised application sheet 3 (revised section III.9) and 3 copies of sheet CGO02 (revised area's) to be slipped into the previous submittal. 2. The wet detention pond supplement has been rvised. The "Storage Volume: Non - SR Waters, Volume Provided" has been revised to the volume provided up to the next outlet. 3. The area shown for the bottom of the vegetated shelf (31,768) is based on the polyline area calculated using CAD. The two area's under the storage tables were calculated using CAD at elevation 9.5 for the forebay and the pond. This was done using an offset from elevation 9.0 and does not count in the berm area as this calculation is primarily to show 20% forebay volume. Because of the way the computer offsets and the way the pond would be built these area's would not necessarily add up to the entire pond surface area at the bottom of vegetated shelf. See color coded sketch for clarification. 4. The drawdown rate for the temporary pool has been revised. We are calculating the head from the next outlet(10 - 11.4) using 1-1/3 and the area of the design storm to calculate the orifice size. This changed the drawdown pipe from a 3" to a 2". The plan sheet (CG105 has also been revised and 3 sets of that plan sheet is included. 5. The calculation for depth (option 2) has been revised to include the depth of the pond from bottom of pond (discounting sediment storage depth) to the bottom of the vegetated shelf. The calculation along with comments on the supplemental form have been revised. 6. Check included with submittal. 7. Sincerely, ��J 4 / Ryan A. Hamblefon, PEAS Project Engineer Rhambleton(a)stewart-eng.com Enclosures ENGINEERING. INNOVATION. SOLUTIONS.T" 421 FAYETTEVILLE STREET RALEIGH, NC T 919.380.8750 SUITE 400 27601 F 919.380.8752 I STEWART LETTER OF TRANSMITTAL I i Nuv �• gggg f BY: o�t,v� o�ocp TO FROM Christine Nelson Ryan Hambleton NCDNER Stormwater Section 127 Cardinal Drive Extension Wilmington, NC 28405 Project Manager, Civil Department, Stewart Engineering, Inc 910-796-7323 (919) 866-4819 DATE SENT VIA 11.11.08 UPS Next Day Air (10:30 a.m.) PROJECT NUMBER PROJECT NAME C8020 MCAS New River Maintenance Hangar COPIES DATE DESCRIPTION 1 11.11.08 revised application sheet 2. 1 11.11.08 su emental forms 3 11.11.08 REvised calculation sheets 3 11.11.08 Revised Sheets CGO02 and CG105 For approval For review & comment Returned for corrections For your use Approved as submitted Returned after review As requested Approved as noted El Resubmit copies for approval COMMENTS Christine, Please find enclosed additional information. Thank you, SIGNED Ryan A. Hambleton, P.E. COPIED TO ENGINEERING. INNOVATION. SOLUTIONS.' 421 FAYETTEVILLE STREET RALEIGH, NC T 919.380.8750 SUITE 400 27601 F 919.380.8752 Michael F. Easley, Governor William G. Ross Jr, Secretary rNorth Carolina Department of Environment and Natural Resources --I `C Coleen H. Sullins Director Division of Water Quality November 4, 2008 Commanding Officer, c/o Carl Baker, Deputy Public Works Officer USMCB Camp Lejeune 1005 Michael Road Camp Lejeune, NC 25847 Subject: Request for Additional Information Stormwater Project No. SW8 080653 MCAS New River Aircraft Maintenance Hanger (P-526/P-651) Onslow County Dear Mr. Baker: The Wilmington Regional Office received a State Stormwater Management Permit Application for MCAS New River Aircraft Maintenance Hanger (P-526/P-651) on October 9, 2008. A preliminary review of that information has determined that the following information is needed to continue the stormwater review: 1. The information submitted on October 30, 2008 in response to the previous request for additional information indicates that the drainage area has been reduced from 367,793 sq ft to 367,022 sq ft. Please update Section 111.9 of the application and plan sheet CGO02 to ensure the documents are consistent. 2. On page 1 of the wet detention pond supplement under "Storage Volume: Non -SR Waters, Volume Provided", please present the actual storage volume not the required storage volume. 3. The surface area identified for the bottom of the vegetated shelf (31,768 sq ft) on the supplement and other documentation is inconsistent with the areas presented in the stage, storage tables (6,560 sq ft + 24,050 sq ft = 30,610 sq ft). Please verify the information is accurate. 4. The drawdown rate for the temporary pool should be based on the required storage volume, not the actual storage volume. The head should be based on the distance to the next available outlet, not the distance to the required storage volume. With the current orifice size of 3", it appears that the required storage volume will drawdown in less than two days. Please resize the orifice so that the drawdown rate for the required minimum storage volume is between 2 and 5 days. Please see the attached schematic previously created by Linda Lewis for clarification. Also refer to Section VI. B.1 of the wet pond Application Review Checklist available on the BMP website if further clarification is needed. The following comment was not identified in the original review, therefore was not considered in the assignment of the fee for additional information. NOw hCarolina 744tum!/y North Carolina Division of Water Quality 127 Cardinal Drive Extension Wilmington, NC 28405 Phone (910) 796-7215 Customer Service Wilmington Regional Office Internet: www.ncwaterqualityorg Fax (910)350-2004 1-877-623-6748 An Equal OpportunitylAffrmative Action Employer — 50% Recycled110 % Post Consumer Paper Carl Baker November 4, 2008 Stormwater Application No. SW8 080653 According to Figure 10-2b of the BMP errata sheet, the depth variable used in the optional average depth calculation should be the distance between the bottom of the vegetated shelf and the bottom of the pond (excluding the sediment accumulation level). The provided calculations appear to use the permanent pool elevation instead of the elevation for the bottom of the vegetated shelf. Please re -calculate the average depth based on the correct depth. Adjust the subsequent calculations based on the resultant average depth, if necessary. 6. Please submit a $500 fee for the additional review required for this application. 7. Please keep in mind that changing one number may change other numbers and require the calculations, supplements, and other supporting documentation to be updated. Verify all numbers are accurate and consistent in the application documents. Please note that this request for additional information is in response to a preliminary review. The requested information should be received in this Office by November 12, 2008, or the application will be returned as incomplete. The return of a project will necessitate resubmittal of all required items, including the application fee. The construction of any impervious surfaces, other than a construction entrance under an approved Sedimentation Erosion Control Plan, is a violation of NCGS 143-215.1 and is subject to enforcement action pursuant to NCGS 143-215.6A. Please reference the State assigned project number on all correspondence. If you have any questions concerning this matter please feel free to call me at (910) 796-7323 or email me at christine.nelson@ncmail.net. Sincerely, �- 906W.-ID Christine Nelson Environmental Engineer ENB/can: S:\WQS\STORMWATER\ADDINFO\2008\080653.nov08 cc: Ryan Hambleton, Stewart Engineering Christine Nelson CWilmington=Regional-Office Page 2 of 2 EXAMPLE AVERAGE HEAD / DRAWDOWN CALCULATION (with outlet set above the calculated min. Temp. Pool Elevation) Given: Required volume to store = 25,000 cubic feet Permanent Pool Elevation = 10.0 Calculated minimum 1" storage elevation = 11.35 Outlet weir set at elevation 13.0 (Temporary Pool Elevation) Total Head, H, = (13.0 - 10.0) = 3.0 Average Head =%(3, 0) = 1.0' (Approximate) Q2 (2 day flowrate) = 25,000 / 172,800 = .145 cfs Qs (5 day flowrate) = 25,000 / 432,000 = .058 cfs Rearrange the orifice equation and solve for Area: A = Q / (Cd (2gh)05) where A is the orifice area in square feet Q is the 2 and 5 day flowrates, cfs Cd is 0.6 g = 32.2 f/S2 And h = average head, feet A2 for the 2 day flowrate = .145 / (.6 (2*32.2*1.0)0 5) = .0301 ft2 A5 for the 5 day flowrate = .058 / (.6 (2*32.2*1.0)05) = .0120 ft2 .0301 x 144 in /ft2 = 4.33 square inches .0120 x 144 in2/ft2 = 1.73 square inches Solving for the radius, R and diameter D: A=TrxR2 R=(A/Tr)0.5 R2 = (4.33 / Tr)05 = 1.17 inches D2 = 2R2 = 2.35 inches R5 = 0.73 / Tr)05 = 0.74 inches D5 = 2R5 = 1.48 inches T.PE. = 13.0 ._I YL,��PPE =10.0 EXAMPLE AVERAGE HEAD / DRAWDOWN CALCULATION (with outlet set at the calculated min. Temp. Pool Elevation) Given: Required volume to store = 25,000 cubic feet Permanent pool Elevation = 10.0 Calculated minimum 1" storage elevation = 11.35 Outlet weir set at elevation 11.35 (Temporary Pool Elevation) Total Head, H, = (11.35 - 10.0) = 1.35 feet Average Head, h, ='/3 (1.35) = 0.45' (Approximate) Q2 (2 day flowrate) = 25,000 / 172,800 = .145 cfs Q5 (5 day flowrate) = 25,000 / 432,000 = .058 cfs Rearrange the orifice equation and solve for Area: A = Q / (Cd (2gh)0 5) where A is the orifice area in square feet Q is the 2 and 5 day flowrates, cfs Cd is 0.6 g = 32.2 ft/s2 And h = average head, feet A2 for the 2 day flowrate = .145 / (.6 (2*32.2*0.45)0 5) = .045 ft2 A5 for the 5 day flowrate = .058 / (.6 (2*32.2*0.45)0 5) = .018 ft2 .045 x 144 in2/ft2 = 6.46 square inches .018 x 144 in2/ft2 = 2.59 square inches Solving for the radius, R and diameter D: A = Tr x R2 R = (A / Tr)o.s R2 = (6.46 / Tr)0 5 = 1.43 inches D2 = 2R2 = 2.87 inches R5 = (2.59 / Tr)0 5 = 0.907 inches Ds = 2R5 = 1.81 inches s ofH c 00- 1 _ 1 1: •. 5:%Wc,Q5\ 5tormw2+erg Gt~idance\ T-P.E_=11.35 -10.0 request fdr additional info: SW Project No. 080653 WAS New River... Subject: request for additional info: SW Project No. 080653 MCAS New River Aircraft Hanger From: Christine Nelson <Christine.Nelson@ncmaiLneV Date: TUC, 04 Nov 2008 14:19:27 -0500 To: Ryan klambleton <rhambleton@stewart-cng.com>, carl.h.baker@usmc.mil CC: David Towler <david.towler@usmc.mil>, Joe Puckett <jpuckett@stewart-eng.com>, Janet Russell <Janet. Russel I@ncmaiLneV Gentlemen, I have attached a pdf version of my second request for additional information for Stormwater Project SW8 080653 - MCAS New River Aircraft Maintenance Hanger (P-526/P-651). I have also attached a schematic that will hopefully help clarify the drawdown calculations. You will also receive copies of this letter in the mail. Please let me know if you have questions. Thanks! Christine Express Stormwater Permitting NC-DENR 080653.nov08.pdf, Content -Type: application/pdf Content -Encoding: base64 Content -Type: application/pdf Average Head & Drawdown Calculation.pdf I Content -Encoding: base64 1 of 1 11/4/2008 2:20 PM www.fbwarlan9.tOm 03) STEWART October 29, 2008 Christine Nelson Division of Water Quality - Wilmington Regional Office 127 Cardinal Drive Extension Wilmington, NC 28405 Re: Request for appeal of additional review fee. Dear Ms. Nelson OCT 3 0 2008 3 Q,Q C;ftoarcOk `DCO� Please find below are the comment responses for the request for additional information for Stormwater project No. SW8 056053. 1. Please find original O&M agreement for the Filter strip. We had thought the "copy" sent with the original submittal was an original. 2. Non -SR Water storage Volume in the wet detention basin supplement has been filled in. Volume used is for "volume provided was for the design storm (non - routed). 3. Supplement - "Temporary pool elevation" was calculated using the 1.5" storm water surface. We will revise to put the surface area of the next riser elevation on the form. 4. The permanent pool surface is correct on the supplement. We have revised the calculations sheet. 5. We will provide "additional important elevations" on page 3 of the calculations. Bottom of pond, Bottom of Veg. Shelf, Normal pool already included. We will add Top of Veg. Shelf, temporary pool (next riser), and design pool surface area to that calculation sheet. As you noted the bottom of vegetated shelf is slightly different in the calculations then the supplement and both have been revised to match. 6. We have revised our calculations to not include the 1-foot sediment accumulation depth and associated volume. We also included the Option 2 Volume calculation for average depth which does provide over 3 foot depth. Per your comment we . have revised our numbers in the calculations and supplement. 7. Our numbers within the example calculation was incorrect but the formula used to calculate the OP2 depth was correct. We have revised both to match the new surface area's. B. We have revised our calculations for determining average head from 1-1/2 to 1-1/3. We had not realized that the calculation had been changed as no one else had made a comment on it over the past year. Thank you for pointing it out. 9. You state that the drawdown rate for the temporary pool should be based on the design storm volume, not the actual temporary pool volume. This goes counter to past comments from Linda Lewis and per 10.3.9 "outlet design", "the outlet device shall be designed to release the temporary pool volume over a period of 48 to 120 hours. The very next figure (figure 10-4) shows the temporary pool elevation at the next outlet (outlet box). If this is a change to the "standard calculating procedure" for calculating the drawdown we will change the calculations for all future projects. For this we have provided calculation with all the possible variations - using drawdown of 1-1/3 and the design storm (storage . required), drawdown from the design storm (as routed in hydro flow taking into ENGINEERING. INNOVATION. SOLUTIONS." 421 FAYETTEVILLE STREET RALEIGH, NC T 919.380.8750 SUITE 400 27601 F 919.380.8752 STEWART account the outlet flow), and drawdown from the temporary pool elevation (next outlet (elev - 11.40') and the resulting pipe for a drawdown rate of 2 - 5 days remains 3 inches. 10. We will provide a plan showing the swale from the driveway pipes. See revised grading sheet CG104 and CG105. We have removed one set of culverts at the southern drive entrance and re -directed the flow from that area to 11-FES. The. offsite drainage area #4 was reduced by 700sf b/c of this change. 11. Additional spot elevations for the mechanical equipment enclosures are provided. The enclosures drain from back to front into the proposed swale. The drainage area map CGO02 was be revised. The impervious area for the entire enclosure(s) has already been included with the calculations (900sf) 12. Spots added to parking lot for clarity. 13. The 6" drawdown orifice is intended for maintenance and / or emergency. Note was added to plans and supplement. 14. Plantings revised and selected by registered Landscape Architect using Table 9-1 of the BMP manual. 15. BMP plants added to planting list and plan to add variety of species. 16. I'm hopefull that I've caught and revised all the numbers to match. 17. Having heard nothing of my appeal we are including the $1,000 re -review fee. 18. Based on responses from the grading contractor the GC has elected to not grade the "triangle apron add on" toward the northern wash rack area. The triangle area will be graded toward a filter strip per the original plan. We do Thank you for your consideration of the proposed change though. Sincerely Ryan.A. Ha�bleto/n, PE ` Project Engineer Rhambleton@stewart-eno.com Enclosures 2of2 LETTER OF TRANSMITTAL STEWART RECEIVED OCT 1 3 2008 BY - TO FROM Christine Nelson Ryan Hambleton NCDNER Stormwater Section 127 Cardinal Drive Extension Wilmington, NC 28405 Project Manager, Civil Department, Stewart Engineering, Inc 910-796-7323 (919)866-4819 DATE SENT VIA 10.8.08 UPS Next Day Air (10:30 a.m.) PROJECT NUMBER PROJECT NAME C8020 MCAS New River Maintenance Hangar COPIES DATE DESCRIPTION 1 10.7.08 Si ned SIA cover sheet. 1 10.9.08 su lemental forms For approval For review & comment Returned for corrections For your use Approved as submitted Returned after review As requested Approved as noted El Resubmit copies for approval COMMENTS Christine, Please find the signature page for the SIA and supplemental forms. Thank you, SIGNED Ryan A. Hambleton, P.E. COPIED TO ENGINEERING. INNOVATION. SOLUTION S.T" 421 FAYETTEVILLE STREET RALEIGH, NC T 919.380.8750 SUITE 400 27601 F 919.380.8752 r Reque.5t Appeal to RE -review fee for SW Project No. 080653 MCAS... Subject: Request Appeal to RE -review fee for SW Project No. 080653 MCAS New River Aircraft Hanger From: "Ryan Hambleton" <rhambleton cdstewart-eng.com> Date: Fri, 24 Oct 2008 16:26:43 -0400 To: <ed. beck@ncmai 1. net>, <georgette.scott@ncmai 1. net> CC: "Christine Nelson" <Christine.Nelson@ncmail.net> Dear Mr. Beck, I am emailing you to request an appeal to a re -review fee required by my reviewer of the MCAS New River Aircraft Hangar project. I have included the original comments and a preliminary response to each in my letter along with what I feel is the reason why the re -review fee should not be required. Upon reviewing the comments I found that most were small errors in transference of numbers between our calculations and the supplement or in the calculations of the pond volume and drawdown, some of which we have not been commented on before. None of the comments resulted in a change to the design of the pond and the changes to the calculations and numbers were incrementally small ... as it's been said we are not making watches. In general if someone could let me know what standard is established for requiring a re -review fee as it seems to be.different between . reviewers and please let me know the status of my appeal as soon as possible as I am required to re -submit by Thursday. I appreciate your time and thank you in advance to any response to my appeal. Ryan Hambleton, PE Project Manager STEWART ENGINEERING 421 Fayetteville Street, Suite 400 Raleigh, NC 27601 Direct 919.866.4819 Fax 919.380.8752 Engineering. Innovation. Solutions. -----Original Message ----- From: Christine Nelson[mailto:Christine.Nelson@ncmail.net] Sent: Wednesday, October 22, 2008 12:33 PM To: Ryan Hambleton; David Towler; carl.h.baker@usmc.mil Cc: Joe Puckett; Janet Russell Subject: request for additional info: SW Project No. 080653 MCAS New River Aircraft Hanger Gentlemen, I have attached a pdf version of my request for additional information for Stormwater Project SW8 080653 - MCAS New River Aircraft Maintenance Hanger (2-526/P-651). I will also send copies via mail. Please let me know if you have questions. Thanks! Christine Express Stormwater Permitting NC-DENR Content -Description: 080653.oct08. pd f l of 2 10/27/2008 1:03 PM Request Appeal to RE -review fee for SW Project No. 080653 WAS... Content -Type: Content -Encoding: application/pdf base64 [Content -Description: Appeal of Re -review fee.pdf [Appeal of Re -review fee.pdf' Content -Type: application/octet-stream Content -Encoding: base64 2 of 2 10/27/2008 1:03 PM C($) S T E WA R T October 24, 2008 Ed Beck Division of Water Quality - Wilmington Regional Office 127 Cardinal Drive Extension Wilmington, NC 28405 Re: Request for appeal of additional review fee. Dear Mr. Beck I am requesting that the enclosed comment #17 be waived requesting $1,000 additional fee for the "additional review required". Past reviews by other reviewers have required additional information above and beyond what is asked here and yet no "re -review" fee was required. What is the standard for when a re -review fee is required? I have gone through the comments and find that of the 17 only one requires an actual change to the design, which is the addition of a Swale and rip rap area. The remaining comments relate to tiny incremental changes in numbers and design, none of which result in a design change of the pond or the project. ❑ 3 are for additional info for grading which resulted in the minor change to the plan ❑ 3 are calculation errors or omissions in transferring from the supplement to the calculations sheet or vice versa but none were major changes. CI 2 are omission of items like the original O&M sheet we thought had been sent and a volume for SR waters which was in the original supplement but didn't get transferred. ❑ 3 are design comments that run counter to what we typically do or are changes that we have not seen within the BMP manual (like the 1-1/2 vs. 1-1/3, or using the design storm volume for drawdown versus the next outlet. ❑ And 2 are landscape comments that may result in changing some plant types in the vegetative shelf. Below are the preliminary comment responses for your preview. 1. We will provide an original O&M agreement for the Filter strip. We had thought the "copy" sent was an original. 2. Non -SR Water storage Volume in the wet detention basin supplement will be filled in. We had this information in our original submission but we needed to resubmit a supplement and that information did not get transposed onto the new supplement. In an effort to link our calculations to the supplement we had modified the excel spreadsheet. This was not acceptable to the reviewer and the data link was lost. 3. Supplement - "Temporary pool elevation" was calculated using the 1.5" storm water surface and put on the supplement. We will revise to put the next riser elevation on the form. 4. The permanent pool surface is correct on the supplement. We have revised the calculations sheet. The difference is 2% between the numbers in the supplement and the calculations in the SIA, which does not effect the design of the pond. 5. We will provide "additional important elevations" on page 3 of the calculations. Bottom of pond, Bottomo f Veg. Shelf, Normal pool already included. We will add ENGINEERING. INNOVATION. SOLUTIONS." 421 FAYETTEVILLE STREET RALEIGH, NC 1919.380.8750 SUITE 400 27601 F 919.380,8752 S T E WA R T Top of Veg. Shelf, temporary pool (next riser), and design pool surface area to that calculation sheet. As you noted the bottom of vegetated shelf is slightly different in the calculations then the supplement. 6. We have revised our calculations to not include the 1-foot sediment accumulation depth and associated volume. We also included the Option 2 Volume calculation for average depth which does provide over 3 foot depth. Per your comment you asked 7. Our numbers within the example calculation was incorrect but the formula used to calculate the OP2 depth was correct. 8. We have revised our calculations for determining average head from H/2 to 1-1/3. We had not realized that the calculation had been changed as no one else had made a comment on it over the past year. Thank you for pointing it out. 9. You state that the drawdown rate for the temporary pool should be based on the design storm volume, not the actual temporary pool volume. This goes counter to past comments from Linda Lewis and per 10.3.9 "outlet design", "the outlet device shall be designed to release the temporary pool volume over a period of 48 to 120 hours. The very next figure (figure 10-4) shows the temporary pool elevation at the next outlet (outlet box). If this is a change to the "standard calculating procedure" for calculating the drawdown we will change the calculations for all future projects. For this we have provided calculation with all CnCC�Y�`- the possible variations - using drawdown of H/3 and the design storm (storage u` required), drawdown from the design storm (as routed in hydro flow taking into 'account flow), dux C A1C.� U the outlet and drawdown from the temporary pool elevation (next outlet (elev - 11.40') and the resulting pipe for a drawdown rate of 2 - S days remains 3 inches. 10. We will provide a plan showing the swale from the driveway pipes. See revised grading sheet CG104 and CG105. 11. Additional spot elevations for the mechanical equipment enclosures are provided. The enclosures drain from back to front into the proposed Swale. The drainage area map CG002 will be revised. The impervious area for the entire enclosure(s) has already been included with the calculations (900sf) 12. Spots added to parking lot for clarity. I'm a little confused as to why you needed them as there were contours available and it was obvious that drainage was going into the storm system. 13. The 6" drawdown orifice is intended for maintenance and / or emergency. Note was added to plans and supplement 14. TBD 15. TBD 16. OK 17. We wish to appeal this decision of requiring a $1,000 re -review fee. If someone could please review the comments, responses, and provide us with the reason this particular project falls into a "re -review fee" option. Sincerely, Ryan A. Hambleton, PE Project Engineer Rhambleton(ulstewart-eng.com Enclosures 2of2 WA74 90 O Y October 22, 2008 Michael F. Easley, Governor William G. Ross Jr., Secretary North Carolina Department of Environment and Natural Resources Commanding Officer, c/o Carl Baker, Deputy Public Works Officer USMCB Camp Lejeune 1005 Michael Road Camp Lejeune, NC 25847 Subject: Request for Additional Information Stormwater Project No. SW8 080653 MCAS New River Aircraft Maintenance Hanger (P-526/P-651) Onslow County Dear Mr. Baker: Coleen H. Sullins Director Division of Water Quality The Wilmington Regional Office received a State Stormwater Management Permit Application for MCAS New River Aircraft Maintenance Hanger (P-526/P-651) on October 9, 2008. A preliminary review of that information has determined that the application is not complete. The following information is needed to continue the stormwater review: mNv,of 1. It appears that the Filter Strip, Buffer, and Level Spreader O&M agreement provided with the application is a copy. Please provide a filter strip O&M agreement with the original signatures. YY fv)'F 2. Complete the Storage Volume: Non -SR Waters section in the wet detention basin supplement. YYIIAof 3. The temporary pool elevation listed on the wet detention pond supplement should be the next available outlet on the pond outlet structure. Please verify the elevation presented in the supplement is consistent with the other documentation. Jhc�n^s The permanent pool surface area identified in the supplement (36,797 sq ft) is inconsistent with the surface area provided on page 3 of the calculations (35,956 sq. ft). Please verify all values are presented accurately and consistently in the various documents. _Jpco>1Ts5}- 5. On page 3 of the calculations, please include additional important elevations in the stage -storage tables in order to ensure consistency among the provided documents (vegetated shelf elevations and temporary pool elevation). For instance, page 3 of the calculations indicates that the surface area at the bottom of the vegetated shelf is 31,495 sq ft, ,however the supplement indicates it is 33,877 sq ft. M,6: f 6. It appears that the permanent pool volume, average depth (OP1), and associated calculations include the 1-foot sediment accumulation depth and associated volume. The depth of the permanent pool is considered to be difference between the permanent pool elevation and the top elevation of the sediment storage and does not include the minimum 1-foot sediment accumulation depth (refer to Figure 10-2b, Figure 10-3, and Section 10.3.4 of the 2007 BMP manual). Please revise the calculations and supplement to consider just the permanent pool in the pond calculations. NOr. hCarolina 1rtura//; North Carolina Division of Water Quality 127 Cardinal Drive Extension Wilmington, NC 28405 Phone (910) 796-7215 Customer Service Wilmington Regional Office Internet: w ,ncvvaterauality.org Fax (910)350-2004 1-877-6236749 An Equal Opportunity/Affirmalive Action Employer — 50 % Recycled/10% Post Consumer Paper Carl Baker October 22, 2008 Stormwater Application No. SW8 080653 7. The average depth calculation (OP2) listed on page 3 of the calculations appears to use inconsistent values. For instance, the average depth calculation (OP2) indicates that 15,679 sq ft is used for both the surface area at the bottom of the pond (ie top of sediment storage elevation) as well as for the area at the bottom of the vegetated shelf. Also, verify the values used in the calculation are consistent with the other documents. 8. The average head used to calculate the discharge rate and drawdown time from the pond should be calculated based on Section 3.5.2 of the 2007 BMP manual. The September 28, 2007 version of the BMP Manual changed the average head equation from H/2 to H/3. Y11a�o�� 9. The drawdown rate for the temporary pool should be based on the design storm Morey and required storage volume, not the actual storage volume. It appears that with the current orifice size of 3", the required storage volume will drawdown in less than two days. Please resize the orifice so that the drawdown rate for the required storage volume is between 2 and 5 days. (YV �O� 10. Plan sheet CG104 indicates that the driveway pipes will drain to the north through a drainage swale. Please provide a plan detailing where that swale drains. Please note that the drainage area map provided with the application indicates that this area is included in the drainage area for the pond, in which case all runoff from the drainage area should be captured and treated by the pond. 11. Please provide additional proposed spot elevations for the mechanical equipment enclosures. According to the drainage area map, CG002, a portion of these enclosures are not included in the drainage area of the pond. Mc:�o,i 12. Please provide additional proposed spot elevations for the southern portion of the parking lot similar to the spot elevations in the northern part of the lot and surrounding storm drain inlets 03-YI and 02-YI. 13.The pond riser detail on plan sheet CG105 indicates that a 6" drawdown orifice with a plug valve is proposed at the bottom of the riser. Please detail the purpose of this drawdown orifice and when it will be utilized. If intended for use during maintenance or emergencies, please identify it on the supplement in the last item under Section II. Design Information. nor 14.According to plan sheet L101, it appears that the pond side slopes above the vegetated shelf are to be planted with soft rush. Please keep in mind that the O&M agreement for wet ponds requires the vegetation around the perimeter of the wet basin to be maintained at approximately 6 inches. Soft rush is not usually used for the side slopes above the vegetated shelf as it can cause erosion problems between the vegetation clumps. Because of maintenance requirements, grass or sod is often used for side slope vegetation. 15. Please increase the variety of plant species selected for the vegetated shelf. Section 10.3.7 of the BMP manual recommends selecting several species of wetland vegetation for the vegetated shelf in order to increase the chance some species will survive permanent pool water level changes. Page 2 of 3 Carl Baker October 22, 2008 Stormwater Application No. SW8 080653 16. Please keep in mind that changing one number may change other numbers and require the calculations, supplements, and other supporting documentation to be updated. Verify all numbers are accurate and consistent in the application documents. 17. Please submit a $1,000 fee for the additional review required for this application. Please note that this request for additional information is in response to a preliminary review. The requested information should be received in this Office prior to October 30, 2008, or the application will be returned as incomplete. The return of a project will necessitate resubmittal of all required items, including the application fee. The construction of any impervious surfaces, other than a construction entrance under an approved Sedimentation Erosion Control Plan, is a violation of NCGS 143-215.1 and is subject to enforcement action pursuant to NCGS 143-215.6A. Please reference the State assigned project number on all correspondence. If you have any questions concerning this matter please feel free to call me at (910) 796-7323 or email me at christine.nelson@ncmail.net. Sincerely, ry - Christine Nelson Environmental Engineer ENB/can: S:\WQS\STORMWATER\ADDINFO\2008\080653.oct08 cc: Ryan Hambleton, Stewart Engineering Christine Nelson Wilmington Regional Office Page 3 of 3 LETTER OF TRANSMITTAL C(::S�" ; STEWART TO FROM Christine Nelson Ryan Hambleton NCDNER Stormwater Section 127 Cardinal Drive Extension Wilmington, NC 28405 Project Manager, Civil Department, Stewart Engineering, Inc 910-796-7323 (919)866-4819 DATE SENT VIA 10.7.08 UPS Next Day Air (10:30 a.m.) PROJECT NUMBER PROJECT NAME C8020 MICAS New River Maintenance Hangar COPIES DATE DESCRIPTION 1 10.7.08 On inal 0&M A reement for Filter Strip 1 10.7.08 Calculations and Narrative (inlcuding supplemental forms, SHWT determination letter report and Geotechnical report) 2 10.7.08 Stormwater Plans folded For approval For review & comment Returned for corrections For your use Approved as submitted Returned after review As requested Approved as noted EJ Resubmit copies for approval COMMENTS Christine, Please find enclosed the package for stormwater permit for the MCAS New River Maintenance Hangar. Another package directly from David Towler will include the following; original + copy of Stormwater Management Application Original O&M agreement for Wet Pond SIGNED Ryan A. Hambleton, P.E. COPIED TO ENGINEERING. INNOVATION. SOLUTIONS.'" 421 FAYETTEVILLE STREET RALEIGH, NC T 919.380.8750 SUITE 400 27601 F 919.380.8752 aboutblank Ryan: To confirm your telephone message of today.... You will mail in the stormwater submittal package for Christine's review so that she will receive the package on October 8. The package will be logged in as received on,October S�for processing. Do not hesitate to contact me if there are problems, 910 796-7421. Thanks, Janet ` 130106 �N1� I of 1 9/30/2008 3:04 PM RE: FW: New River Maintenance Hangar Subject: RE: FW: New River Maintenance Hangar From: "Ryan Flambleton" <rhambleton@stewart-eng.com> Date: Sun, 28 Sep 2008 15:05:19 -0400 To: "Christine Nelson" <Christine.Nelson a ncmai1.net>, "Janet Russell" <Janet.Russel I@ncmai1.net> CC: "Joe Puckett" <jpuckett@stewart-eng.com> Janet / Christine; I was emailing to request a submittal date for the MCAS New River Maintenance Hangar. Based on conversations between Christine and Joe Pucket at our office I. understand we are at least on track with our calculations. Can we submit Thursday, October 2nd? Please let me know if that works with your schedule. Thanks, Ryan From: Christine Nelson[mailto:Christine.Nelson@ncmail.net] Sent: Thu 9/25/2008 11:40 AM To: Ryan Hambleton Cc: Janet Russell; James Phillips Subject: Re: FW: New River Maintenance Hangar Ryan, I have shown Linda your e-mail with Jim's that his experience is ok for determining questions. Christine Ryan Hambleton wrote: Christine, expanded soils experience. She has agreed the SHWT. Let me know if you have I talked with Jim Phillips (our environmental manager who made the call) and have a couple "soil qualifications" that he has completed. Graduate studies under Dr. Jim Gregory, CPSS at NCSU 1994 - 1998 Hydric soil determinations in Great Dismal Swamp Wildlife Refuge Dare County Bombing range Wetland delineations (which require hydric soil determinations) Stewart Engineering (various projects) 2000 - 2008 Wetland delineation field training course (NCSU) 2006 Stream Determinations for calls on stream locations (submitted to Corp. of Engineers and DWQ) Stewart Engineering (various projects) 2000 - 2008 Let me know if wetland determinatins and stream calls qualify him for this type of work. I can get a list of actual projects and Environmental Assessments that he has submitted in the past. Thanks for checking in on his qualifications. I of 2 9/29/2008 8:40 AM Re: FW: New River Maintenance Hangar Subject: Re: FW: New River Maintenance Hangar From: Christine Nelson <Christine.Nelson@ncmai1.net> Date: Thu, 25 Sep 2008 11:40:03 -0400 To: Ryan Hambleton <rhambleton cr stewart-eng.com> CC: Janet Russell <Janet.Russel I@ncmaiI.net>, James Phillips <jphi llips@stewart,eng.com> Ryan, I have shown Linda your e-mail with Jim's expanded soils experience. She has agreed that his experience is ok for determining the SHWT. Let me know if you have questions. Christine Ryan Hambleton wrote: Christine, I talked with Jim Phillips (our environmental manager who made the call) and have a couple "soil qualifications" that he has completed. Graduate studies under Dr. Jim Gregory, CPSS at NCSU 1994 - 1998 Hydric soil determinations in Great Dismal Swamp Wildlife Refuge Dare County Bombing range Wetland delineations (which require hydric soil determinations) Stewart Engineering (various projects) 2000 - 2008 Wetland delineation field training course (NCSU) 2006 Stream Determinations for calls on stream locations (submitted to Corp. of Engineers and DWQ) Stewart Engineering (various projects) 2000 - 2008 Let me know if wetland determinatins and stream calls qualify him for this type of work. I can get a list of actual projects and Environmental Assessments that he has submitted in the past. Thanks for checking in on his qualifications. Ryan -----Original Message ----- From: Christine Nelsontmailto:Christine.Nelson@ncmail.net] Sent: Wednesday, September 24, 2008 3:19 PM To: Ryan Hambleton Cc: Janet Russell Subject: Re: FW: New River Maintenance Hangar Ryan, I have discussed this project with my supervisor, Georgette Scott, as to whether it can be accepted into program even with the outstanding SHWT issues. She supports the decision not to accept the project until the soils issue has been resolved. The SHWT needs to be nailed down so we all know how to proceed. Were you able to identify any soils qualifications for the person that made the calls? Soil workshops, training, other soil reports they had completed? I of 2 9/25/2008 11:40 AM (: FW: StpIT to Normal Pool Calculation for MCAS New River 7 Subject: FW: SHWT to Normal Pool Calculation for MCAS New River From: "Joe Puckett" <jpuckett cr stewart-eng.com> Date: Tue, 23 Sep 2008 16:41:37 -0400 To: <christine.nelson@ncmai1.net> Christine, When you get this email, please feel free to call and I will be happy to explain the following attachments. (919) 866-4829. Summary I calculated the groundwater seepage into the pond using a flow net. A flow net is a graphical solution for steady, two-dimensional, incompressible fluid through a homogenous medium. Using the permeability of a fine sand as determined in the geotechnical report yields; k=1E-4 cm/s: Below 10 feet the permeability is much less because the site has clays which have a typically permeability of 1E-7 cm/s. The attached calculations show using the following equation: Q=kHI N�m� which is a modification to Darcy's Law for groundwater seepage from flow nets; yielded an average flow of 0.2296 cubic feet foot of dam per day. If the SHWT was equal to the existing ground surface and this rate applied into the 33,761 Surface Area at Normal Pool Pond, then the normal pool would rise 0.34 inches in 5 days with the assumption of zero discharge from the pond. Also, attached is an updated stormwater cross section sheet, where we ran the pond with the assumption that the normal pool was at 10.75 feet above mean sea level (original proposed normal pool at 9). Because the average of the two SHWT bores previously taken average to 10.75. This routing of the pond required the riser rim to be adjusted to an elevation of 11.40 feet above mean sea level to insure that the 1.5" event was captured and discharged over 2-5 days during a SHWT event. This routing assumes that the seasonal high water elevation raises the starting water surface elevation regardless of the soil permeability. With these two calculations it appears that the pond design and methodology we are proposing should be acceptable for submission regardless of what the actual SHWT is determined to be, because of the low permeability of the soils. Based on the soil k value and the proposed routing of the pond using a starting water surface elevation of 10.75' we believe that no matter what the SHWT is determined to be that our design will meet the necessary requirements. Please review and call/email with any questions. Joe Puckett, PE, LEED5 AP Project Engineer STEWART 421 Fayetteville Street, Suite 400 Raleigh, NC 27601 T 919.380.8750 x229 F 919.380.8752 D 919.866.4829 Engineering. Innovation. Solutions. PPlease consider the environment before printing this email I oft 9/24/2008 12:48 PM 21-6 CIYIL IMOINIIRINO Rli[RINC[ YIMYfL Example 21.1 A 9 in (25 ) dimteter well u pumped In the rate of W gal/min (0.2 ma/ran). The aquifer Is HIS it (30 m) thick. After some time, the well .ide, care in and are reptaced with an 6 in (20 an) diameter tube. The draw - dowm e 6 ft (2 m). The waver :able rerovere its original thick.,, 2500 It (7:10 at from the well. N91at will be the xleanly flow from thr new wen'.' SI Solution 25 cut _ 12.5 ran (0.125 m) y'=30m-21.=2Sm ❑arrange Eq. 21.25 to determine hydraulic rondurtir- iq foam lire gi..v odeaca flor. F = Qlz(r2) Too, - YD �n° i50m1 0.2 � �10 �0126m =0.001774 al (0.007957 .n/I) Far the relined well, z _ 20 ere = loan (0. 10 m) Use, Fq- 21.25 to sou far life new flow race. Q _ ft(VI-VI) . s In ra� I I I (.30 m)x - (26 uQx l = r. (Sl-( 14 min ) 00 m /II hI �LLIO mI = 0.195 on,,/will Curlommy U.S. Solution J in = 0.375 It rz= / in\ 2h1 yx=l/m rt-Eft=94 It.OIY222t \I Q= I .f0 m n 1 �O = 0.1114 ha//sw lie.trrwtge :.G. 21,23 to Hall 111e Irvdraalk r awn,ti,im QIn \rx� K = z :(yz , -vx) m ft �50 gal �14.10 II-� In fens liar 11.375 ft r. ((1an I,,- - (94 f I I = 173.4 gal/day-ft' For the relined will. 8 it, _ = Oxii it 2)(12� Use Fq_ 21.25 Intent— far the new Sow rate _ rh'(y/i -y:) Q In Po) rw3A gi1, ((10Yh)x-(94a)=) Cay.ft = trJ n S I,1 = 71.012 gal/dm' 12. UNSTEADY FLOW When awamg fit bogins the refereed wirer also runte, flow the aender alwac the .gmitbrow, acne of depresiew. TO ..far,. hit. 21.2G rfmrfm he wr& and It noveeallibnum wwle,go Is mI,01111. 9ouceailibrium solutions to wool problems here been foraulateal in t,,w, of diutelnlonless nnmbn- cFor sanall drawdowos corrpand with the initial thickness of [Ire soils,, the Thel...... jinn for 11f, drawdowr of a distance r from the well load attar pumping for tlnw 1 _ (Q) let,.) _ W u) 2128 I:T it,(.) is a th o .wiodra. weli fealfwa. 'I bought it is pru- siblecoobtain W(a) from Ir, fwrroctin& u from ;I (a) is acre diffit,uh, The USatiansbip bctwar n wall W(r) is ofteu 8i,,i in tabnlar nr grnphiaJ &urn. In Eq. 21, t0, S Is the :uluifer etompn rmrstuul. 11(a)=-0.57721E-)1'11 fun a 2c .l u1 ' (3)lT) (4)(C))_ 2r29 rz5 _ rz5 21.30 Y-4EYi 47'1 A .... dingly, for au, two different cinaes in the puntplug pie. It rsz=Ye-0=1 Q I(IS '(ul)-1;(uz))21.31 4,KY 14 � 1 If n <O.GI. then JnroSs equation can M trod_ 03 j 1- ., 17, PUMPING POWER ' Pario:I, tt" of pumps are used in wells Pmblout, will,eveasive actual lift we avoided b. the m-e of sill. racrsfole. pumps. f"utopia, pile,, con he determined front tF.o b,drarlie (water) alwcr.ryamiom..,wilted in Ch. 18. The total jOctal 1 Set a .f stmn. fife. veloc i bred lire down i rl fat .ad ruin., errirancel the u ! tt"'woe,a i sce,no. The thow.-Williona, eltulakar I, I$nowonl, I,,] with awe'6mew ofC=1011todt. r n. the piPL friction. i •. 14. FLOW NETS l Croundwaler serMge it from location- .thigh h�hanlin held to location, of lower hydraulic had. Relatively `, mmplex tw..dunetdoual problew calf, be ccloluarterl ( -mg a graphical technical, that how. _. the &,e lee 1• if, htdrauh, head along the flow path The result. „PIng goLpIIX ruprra titmion of preinre and flow, path i called It ffom rot. ...... R•RT[R 21-7 The flow net mneept hrn• is limited w o I-, where file flaw is swady, lwr.dilanusional. incompress- ible, and through a homo,neous mrdinm, wed where the liquid has a mrlstant v ,c siq, Thi, it,,he nital rase of,rovnawater seepage. Flow net' are conurecteIt from s,racolme, aid egol,w. semis line. Shrwahara (flow fines) ,how, the Path Luken by In, ",ra'a Equl"'wital Sol, are c.mour limn: of instant hydraulic it, The object u. a Kraphwal Out net snluaion is to retrnet a network of Ilaw paths (mitred by Wa stmwainro) and ryaal .unsure drops (horcfard byLrlui- pmenCal liars) N. ]]full ll s wrcc,,. rcrn.mes and It untstaut anaaunt of fired Slow+brtwo..n am two r rewn- lines. . Pot, net= are according m I!It faiteen, ful­ Rule 21.1: StU,.mi n.m enter and lean• Pervious ,,[a, Its Perpendicular to those surfers. Ruf Ell: StletUallues Uflunath tn.l f senpg. Salute,n f there byllocontattic I r ) Its) p- t C all t l._ pars 1 [art ,rwl udli I P ,adnn') that surface. Rule 21.3: SI fw.lims I...• pwallci to but Iwu:ot .omit mpereaw, ewfac . that arc etreemlo s. RWe 21-6: Streamlines xre 1uv:Jlel to the flmr di:ecainn. Rate 21.5: Fiptflag,wgOl din., are drawn perpendicular to strearallinet,such hat tho re,arldn,cells n 1 mxj t h>q w Ill i t. I ere Te areucall it .hould la. p...Ihle m draw a peffirr rode within reachlet] lh.rt coach. all four M 1 -o. urn though fit, MI i, rot m.t a 11 1 :are. uWat 21.3 Wofl Fm1C1Yn Wall for Various Varucs o: v I0 TO 3.0 4.0 50 Sib 7.0 6.0 0.0 xi U219 0.049 0.013 0.0038 UWlI O.CA036 0.00012 1.ONKt, 0.000012 nl0-t I.S2 122 0.91 0,70 0.56 0.45 0.37 0.31 0.211 .10-2 .LM 3,35 296 2.66 2,47 L W 2.15 2.01,3 !.92 sio-a Cu 5.61 a.23 1.9.5 .1.73 4.54 1,39 4.2G .1.14 x10-' 6.63 7,94 7.60 7.25 7.02 6.64 6,69 6.51, 6a4 x10-.• I0,94 10,24 9.E4 9.55 9.33 9A.1 8.m 6.gi S.T4 •• x10-s 1:121 12.5.5 123: 1LE5 11.63 11,15 IL2J 11.1G 11U4 x in-, 15.51 14.85 14a. II.15, 13.93 13,75 1360 13.46 13.34 x 10- 17.61 17.13 16.74 16.46 16.23 16.05 15.90 1111.76 15.65 x 10-o 20,15 19.45 1905 16,76 18.51 18.35 16.20 18.07 17-95 xto-tn 2145 21,76 21.35 21.06 2U.84 20-m 20.50 20.37 21125 " x10-U 21.75 2406 13,65 23.36 23.11 22.96_ 12.81 12.61 x10-1t 27.05 2636 25.96 25.G7 25414 25,26 25.11 21.97 24.66 .. 110-^ 29.36 2n.6G 26.26 27.97 27.75 27.56 27.11 27.26 27.16 If10-er1 31.66 30.97 30.56 30,27 30.05 29.87 29.71 29.56 29.46 x10-Io 33.9E X3,27 32.86 32.58 32.35 32,17 31U2 31.8E 31.76 Y u wpdnrad bon L. K. VVr:al, '%Innab lot Rvmmfnirg rume.bal,tr N Nuer Ihuany 11.I, L .uh s,n 1 un-f . ;° •x In o vtugfop, tCaf]mhaI U.S. c.vlogia Sur.e1, I9J2, te.ter-9upwb ram'+ s;. V NOilff10N 11 ♦YlLIC1T10Nf INC. i1=11laY ..Of [f R 10N1L iY1 OLI CT10Nf•INC. ;wVmv_�'. 21-8 CIVIL IMOIM![RINO P[IIPINC[ YRNYIL �_ ill 21 1 Etwintillatild l 1. not' I 1 r ons.uf P la'ad. ,colar to t1losis selfines %tar, ff. ral trill, differing d 1, fland an be door d II p l o I cararet. certerall, three to Five, streamlines, are suffineat for usual graph- ical evaluation.. The dze of the tells ie detennin d by the amnlam of haerser:ing slreamfims and Narnaren- Ind Imlvs. As long a, the rulm are folleard. the ratio Of not flow chmmeLw to e.IriPo:ential tiro, will he apnfoxfina l real leg;udlecs of wl"ther are grid is roars. or lines ii,ae Lt 3 h s Slav net,for ndoeldl n Cases. A alfill t f a flea, ia.t, will le-111 t. 1141ify the ado and lial, 'rel hand. 1S. SEEPAGE FROM FLOW_HETS On H t net I, donell. it arr he used to calculate the. ,arg Fill the le f Hall, d I \l, berms the s,,vl is owlet Then. the m ter of I, d,,ea,mI drop fin. betxren lailaileteld ho's ,, nated. The total hydraalk head. 11, is determined ;a it function of the water surface, level.. Q=hlf `�I [widthr, 21m 11=HI—Ha / 21a 18. HYDROSTATIC PRESSURE ALONG FLOW PATH The hydrostatic prell at egaipolealad drop j (mura- ing the last if., on the dowrulreon side as rtroJ in a fl. net with a canal of A'v equipou+mial drops 6 given to fal. 0-1.35. If the point .near, im'Istigi nd is along tile, tn.uom of a dun; or older arurmra. the hydnntrall pia ore is referr..i ro a, ui fife przaare. Since gdif, dre to velocity is negligible, a0 aliifi is tine to the neutral 'pare pnvnrc. Therefore. nentmf 11111rro L, a, -- moll wish uplift Prosare. P. = IIf'. 2L35 1 ®®�oiasmii��� me.mDo.®e�® dos O 9e 1 _ t 'ee of fata c MI \'aactiar.1Pow _ } eanr data to gin of now drain a is n;L �I'll2 'i l'tc tr re, to rs rt Fqun 2f.3 lbttt al f ens If tho point Irving i oestigard is lamwi n di.umn:: below the datum, then the poe—on, at the Paint is,ill'a by 1,1. 21.36 If file point being in"'Idatd b ubme rho datuur z i negalive The nctoal uplift filer I,., urfa,, of erco A ln,ean by Eq 137 \ is he to,foral t,,, Oaffici,of. reined ,be feartion rifle ( that I, - o tit fit,! hellos ,liti,flelne. no oil,\ t H fill f t rd rock tv. parents Firestone, a- itona, it villas front 05 In 1.0. For natiterviera,, material ch as n.0 ble or gfanib,_ it ran be as low a 0-1, H=0'ptIA 21.37 A,'I'abin 21.1 indirmes wine clay l.,, ut in"'. trionidt m prohibit We Passing of ware', thrower, the hydrostatic uplift Prosare beltra, a day laver wn will be tranatoiud thmngh the clay layer, The transfer gearetri for a' k hotel is coniplex.finding f,tanatel, 1 the alraha Of iffliftf Ce i'IF.It. UPWardfrit: ,it p 1 rot d ostm 'oessate hi s, known as, neon. A famor of •atm, agalmr slave of at teat 1.5 is dilatable. that sward prevnre (FS)he,.,= n tifr vote 2138 a p pre: 17. INFILTRATION Aftifersean b, nvhalgd (refilled) in a runes of md- ant and ortihri'd x;p'e. 'Phi Horton "nation gins n totter hind on the fnffftoone. caprcit, (in fnchea Or rainfall Per unit time), fliel, is the capacity of all agni@a to absorb rater floor a saturated source abate, :ion of time. When the rainfall supply exnrds the infil:ra thou calamity, infilnatiou deroa. eywnen- tialty over that. In Hy. 21.39. f, is the final or a I& Iiblear tonal fo is the initial infiltration raparily, and f, i :he ad lmTJon .,.il, at lime 1. k is an infiltration dome evaalln tilh dinneaia, of title-' dew,ur d full if denad, riry InfJbution tell. Ill =fe+(fr—M, ` 2I.s2 GROUNDWATER 21-9 The cumulall,, ndiltr;diial x'lll lrl e:artespond :o tilt' joar,ine, in Ivate, table de,litioadto h ff t f Pu Fkave,er. fit.,. in t table 1 lion an be cilrennumdf lanowldi, cifthe rattler Pert Infiltration rates file a:tenldara. silly wlix are appeal in;ately 50t/o of those for .and. Cla. infiltration rates ue a fin vinmtely 10%of Ihas for sand. The actuld ir- %hratlon rate at any time b egnal (in the Horton model) to fire ,made, of the rairbill intecniin ill).. and ;he in- statavenne refill f =i li < fll 2140 f=f; 1i>hl 21.41 The cvmaletwe infiltration o er Late rs F,=fd}(')(1—e—it) 214 The average infiltration are a found n, dividing Eq. 21A2 In the aurat nt of iafihorta on F' 21,13 faean.r.. •POIf\f 10 N A •V[L I C A T 1 0 N[ INC. ] IRO![11 S10N A I I C A T I O NS I INC. I MtAS - IIEW T-44M I I PROJECT PAGE OF I I c REFERENCE PROJECT NO, I I I CLIENT DESIGNFP DATE STEVVART I I I CIIECFEP DATE r a ENGINEERING. INNOVATION. SOLUTIONS:' 2'ulm^u•x;I cr, � 1Z ,ILE,!d: e.+iq.,gn qe E.n tPw.r.nvwmuv.wln STEC .)E60 ,0.6350. E:i � \ V SHWT BORE # EXISTING DEPTH TO APPROXIMATE GHOUNO ELEV. SHWT SHWT ELEV. \ \ I 11b0 12 1 11 50 PUM' J 11 SO _ 18 10.00 -eVG SHWT IN POND = 10.75 \9\ 1 I \ GT10 \ /r ®ems #a ' �---------- - - - - - - ----------=s Y % Y - WET DETENTION BASIN NORMAL POOL o 9.0 S m 0 F� M Nr -s 0 C(v S T E WA R T September 16, 2008 NCDENR - DWQ Permitting (Wilmington) Christine Nelson 127 Cardinal Dr. Wilmington, NC 28405 Re: MCAS New River Maintenance Hangar Seasonal High Water Table Findings; Dear Ms. Christine Nelson; We are submitting this report of findings for the Seasonal High Water Table (SHWT) at the proposed wet pond for the MCAS New River Maintenance Hangar Project. The soil investigation was conducted on September 12" by Stewart Engineering, Inc using a hand auger at the locations attached to determine the soil conditions for the SHWT at the proposed wet pond. The surrounding area is an open field located just north of the air field and adjacent to the existing wet pond. We observe that the field is most likely a fill area and is generally flat draining west to east. A report will be submitted separately to NCDENR (c/o Vincent Lewis) with the following information. Two borings were made using a hand auger (Bore #1 and Bore #2) to determine the SHWT. Mottling of the soil indicated that the SHWT was found approximately 12" below surface at bore #1 and 18" below at bore #2. Boring Approx. Existing Depth to Approx. Proposed Ground Elevation SHWT Elevation of Normal Pool SHWT #1 12.5 12" 11.5 9.5 #2 11.5 18" 10.0 9.5 The proposed pond is located adjacent to an existing wet pond which normal pool elevation is at elevation 6.5 feet. The proposed pond location was selected to prevent BASH (Bird Aircraft Strike Hazard) at the airfield. The discharge point for the pond is located below 7'. Additionally the current design uses minimum pipe slope from the proposed hangar to the pond with the inflow pipe invert at 9.0'. Based on the SHWT at the pond we propose to raise our normal pool elevation to 9.5' which would bring it to within 6" of one of the findings. This normal pool would inundate approximately 100' of pipe which we proposed to be gasket sealed. Please let me know as soon as possible how we can move forward with the submittal for this project. Sincerely, Ryan A. Hambleton, PE ENGINEERING. INNOVATION. SOLUTIONS." 421 FAYETTEVILLE STREET RALEIGH, NC T 919.380.8750 SUITE 400 27601 F 919.380.8752 t I -_ IfLXVI `} ------I `� I�------------ -------- r-------- r j/ 9 B10-RETENT ON BASIN YD R5ER OR4L zw. nrvLnw scx .mo. - waoxo cvRiav [m Qo - JKICw ew ® rruu .ru w2 Rds IR me.w ww rw - RCQ 1[I3X 1dY OM:s%UI ro sror+snrz. t �TEWART i GRAPHIC SCALE wvs�c Vff ` PACNAGEt fINX 6UBNIi K 0896V! RE: MCAS Aircraft Maintenance Hangar Subject: RE: MCAS Aircraft Maintenance Hangar From: "Towler CIV David W" <david.towler@usmc.mil> Date: Wed, 3 Sep 2008 14:40:02 -0400 To: 'Janet Russell" <Janet.Russell@ncmail.net>, "Ryan I-Iambleton" <rhambleton@stewart-eng.com> September 11, at 11:00 is good for me. Thanks. V/r, David W. Towler, EI Marine Corps Base, Camp Lejeune Civil Engineer Public Works Division, Bldg 1005 Civil Design Branch Phone: (910) 451-3238 ext. 3284 -----Original Message ----- From: Janet Russel].(mailto:Janet.Russell@ncmai.l.net] Sent: Friday, August 29, 2008 15:10 To: Towler CIV David W; Ryan Hambleton Subject: MCAS Aircraft Maintenance Hangar August 29, 2008* MCAS Aircraft Maintenance Hangar* Ryan & David: The Express stormwater submittal meeting for the Maintenance Hangar has been scheduled with *Christine Nelson on September 11, 2008 at 11:00 AM* here in the Wilmington Regional Office. Please review the submittal requirements, attached. Particularly note that wepreferthe plans to be folded, 9" x 14" if possible. Please respond ASAP to reserve and confirm the submittal meeting date / time. Thanks, Janet Russell Express Coordinator I of 1 9/3/2008 3:37 PM RE: MCAS Aircraft Maintenance Hangar Subject: RE: MCAS Aircraft Maintenance Flangar From: "Ryan Hambleton" <rhambleton@stewart-eng.com> Date: Wed, 3 Sep 2008 14:37:43 -0400 To: "Janet Russell" <.Ianet.Russell@ncmail.net>, "Towler CIV David W" <david.towler@usmc.mil> Janet, I just realized I didn't respond to your email from Friday. I wanted to make sure we are still good for the llth at llam for the MCAS Aircraft Maintenance Hangar. Thanks, Ryan -----Original Message ----- From: Janet Russell[mailto:Janet.Russell@ncmail.net] Sent: Friday, August 29, 2008 3:10 PM To: Towler CIV David W; Ryan Hambleton Subject: MCAS Aircraft Maintenance Hangar August 29, 2008* MCAS Aircraft Maintenance Hangar* Ryan & David: The Express stormwater submittal meeting for the Maintenance Hangar has been scheduled with *Christine Nelson on September 11, 2008 at 11:00 AM* here in the Wilmington Regional Office. Please review the submittal requirements, attached. Particularly note that we prefer the plans to be folded, 9" x 14" if possible. Please respond ASAP to reserve and confirm the submittal meeting date / time. Thanks, Janet Russell Express Coordinator I of 1 9/3/2008 3:37 PM aboutblank August 29, 2008 MCAS Aircraft Maintenance Hangar Ryan & David: The Express stormwater submittal meeting for the Maintenance Hangar has been scheduled with Christine Nelson on September 11, 2008 at 11:00 AM here in the Wilmington Regional Office. Please review the submittal requirements, attached. Particularly note that we prefer the plans to be folded, 9" x 14" if possible. Please respond ASAP to reserve and confirm the submittal meeting date / time. Thanks, Janet Russell Express Coordinator I of 1 8/29/2008 3:10 PM RE: MCAS New River Hangar Subject: RE: MCAS New River Hangar From: "Ryan Hambleton" <rhambleton@stewart-eng.com> Date: Fri, 29 Aug 2008 10:44:36 -0400 To: "Janet Russell" <Janet.Russel l@ncmail.net> 11 qP +�.r- l0 t 3j I can do the 12th at 11 am. the 15thbetween 12:00 and 2:30 or the 16th at See if those times work... Thanks, Ryan any time. -----Original Message ----- From: Janet Russell [mailto:Janet.Russell@ncmail.net] Sent: Friday, August 29, 2008 10:36 AM To: Ryan Hambleton Subject: Re: MCAS New River Hangar Rryan: Christine will be on vacation a couple of days that week. Please give me 2 or 3 additional dates to take to her. The llth may be a possibility, but the loth is not available. Thanks, Janet Ryan Hambleton wrote: Janet, I would like to schedule the Express review submittal meeting for the MCAS New River Hangar project. Can you please let me know if Christine and yourself are available for either of the following days; Wednesday September loth (anytime after 10:30 am - or before 2:30pm) Thursday September llth (anytime after 10:30 am - or before 2:30pm) Thanks, Ryan -----Original Message ----- From: Janet Russell [mailto:Janet.Russell@ncmail.net] Sent: Monday, August 25, 2008 2:27 PM To: Christine Nelson Cc: Joe Puckett; Ryan Hambleton; Feinman, Wes; david.towler@usmc.mil Subject: Re: MCAS New River Hangar Please don't forget to get your submittal meeting scheduled. Janet Russell Express Coordinator Christine Nelson wrote: Joe, The concept seems fine with me. Does that existing pond have a state stormwater permit? If so, you might consider modifying the existing pond to accept the additional stormwater. Christine Joe Puckett wrote: I of 2 8/29/2008 I0:52 AM aboutblank Thank you. We're all set then for the 24th. Janet Ryan Hambleton wrote: Thank you Janet, Carol said we will not need to meet since we had a seeping meeting, so the July 24th date is good with Christine and we can drop off the package for Carol's review at that time. Thanks, Ryan -----Original Message ----- From: Janet Russell[mailto:Janet.Russell@ncmail.net] Sent: Tuesday, July 15, 2006 9:27 AM To: Ryan Hambleton; Baker CIV Carl H; Towler GS05 David W; Carol Miller Subject: MCAS New River Aircraft Maintenance Hangar July 15, 2008 *MCAS NEW RIVER AIRCRAFT MAINTENANCE HANGAR *Gentlemen: The Express Stormwater submittal meeting has been scheduled with *Christine Nelson on July 24, 2008 at 10:00 AMA here in the Wilmington Regional Office. The applicant is required to attend the meeting. Please review the submittal requirements attachment prior to the meeting. Unfortunately, Carol Miller is not available to meet with you for the erosion control submittal next week. Please contact Carol directly to schedule the erosion control plan submittal. Carol's email address is above; her direct telephone number is 910 796- 7313. If we need to push the stormwater meeting until the following week so that you can meet with everyone when you come to Wilmington, let me know and I'll set that up with Carol & Christine. Thanks, Janet Russell Express Coordinator I of 1 7/15/2008 12:09 PM aboutNank July 15, 2008 MCAS NEW RIVER AIRCRAFT MAINTENANCE HANGAR Gentlemen: The Express Stormwater submittal meeting has been scheduled with Christine Nelson on July 24, 2008 at 10:00 AM here in the Wilmington Regional Office. The applicant is required to attend the meeting. Please review the submittal requirements attachment prior to the meeting. Unfortunately, Carol Miller is not available to meet with you for the erosion control submittal next week. Please contact Carol directly to schedule the erosion control plan submittal. Carol's email address is above; her direct telephone number is 910 796- 7313. If we need to push the stormwater meeting until the following week so that you can meet with everyone when you come to Wilmington, let me know and I'll set that up with Carol & Christine. Thanks, Janet Russell Express Coordinator 1 of 1 7/15/2008 9:26 AM Stormwater Routing and Calculations For the proposed MCAS New River Hangar Camp Lejeune, North Carolina Prepared for Whiting -Turner Associates Prepared By Stewart Engineering, Inc. S STEWART July 14, 2008 Revised September 8, 2008 Revised October 8, 2008 Revised October 28, 2008 C�'T OlFar,7� CT 3 0 2008 BY: 6L 7Y0 Stormwater Routing and Calculations For MCAS New River Hangar Camp Lejeune, North Carolina .Prepared for: Whiting -Turner Associates 0333117Q Z iO-yfr�� Prepared by: Stewart Engineering, Inc. 421 Fayetteville St. Raleigh, NC 27601 919.380.8750 Stewart Project No. C8020 July 22, 2008 Revised September 8, 2008 Revised October 8, 2008 Revised October 28, 2008 Table of Contents 1. Table of Contents & Narrative a. Groundwater Infiltration Consideration 2. Site Information a. QUAD Map b. FEMA Map c. Soils Map d. Pre-Dev and Post-Dev Drainage Area Maps e. Rainfall Data 3. Hydraulic Calculations I a. 10 Year & 25 Year HGL Profiles - StormCAD b. Peak Flow Analysis - HYDRAFLOW 4. Hydraulic Calculations II a. Pollutant Calculations b. BMP Supplemental Forms i. Wetpond Basin ii. Filter Strip c. Dissipater Calculations d. Buoyancy Check e. Ditch Flow at Pond Outlet STORMWATER ROUTING AND CALCULATIONS MARINE CORPS AIR STATION CAMP LE]EUNE, NORTH CAROLINA EXECUTIVE SUMMARY This report summarizes the hydraulic calculations for the storm drainage system and BMP's onsite. The site is located in Camp Lejeune, NC at Marine Corps Air Station New River. The proposed project is a New Maintenance Hangar and associated parking. The new hangar is proposed to be constructed on existing impervious, while the parking is proposed to be located in an existing open field. The hangar and parking are proposed to be treated by a Wetpond Basin. The design storm for this project is the 1.5" storm. According to the NC State BMP Manual, the design storm should be discharged level spreader unless the basin has been designed for removal of 90%, which is the case for this project. Site Information The existing Project site is located at Campbell Street and McAvoy Street in Marine Corps. Air Station (MCAS) New River, NC and is currently a mix of an existing gravel parking lot, existing tarmac, and open areas. The site drains to the New River and is outside of any known floodplains, wetlands, and Water Supply Watersheds. The latest version of the United States Department of Agriculture Soil Conservation Service Soil Survey of Onslow County, North Carolina map indicates that the on -site soils are Urban Lands and Goldsboro - Urban Land which are classified as Hydrologic Soil Group D. Per FEMA Flood Insurance Rate Map 37204364001, dated November 3, 2005, no 100-yr Floodplain is present within the project site. Proposed Improvements The proposed improvements associated with this project include the demolition of the tarmac. A new Hangar is proposed for the site with approximately 72,971 sf of building footprint along with associated sidewalks, driveways and parking (approx. 78,524 sf). As a result of the demolition of existing impervious surface and the proposed parking the project will result in 78,524 sf net increase in impervious area. Design Requirements Due the location of the site, the project must capture and treat the runoff from the 1.5" storm. Since the site is located within the BASH (Bird Aircraft Stirke Hazard) zone for the MCAS airfield, the Wetpond is proposed on the northern most portion of the site adjacent to an existing Wetpond. Conclusions Based on the results of this analysis, the Wetpond is adequate to treat the proposed new impervious on site. The table below is a summary of the results from Hydraflow Hydrographs. The proposed future condition was modeled for each sub - basin going to a storm inlet. The results also show that we modeled just the 1.5" design storm (In the calculations provided this is labeled as the 3-Yr storm due to limitations in the software this label cannot be revised.) The table below shows that the entire design storm goes to the Wetpond Basin and that the Combined Post Developed Flow is less than the Pre -Developed Flow for the entire project for the 1- Year 24 hour storm event. Hyd. Hydrograph Inflow Peak Outflows (cfs) No. Type Hyd(s) Description 1-Yr 2-Yr 1.5" 5-Yr 10•Yr 25-Yr 50-Yr 100-Yr 1 SCS -- 14.77 21.58 2.28 34.89 45.39 60.78 73.65 88.09 PRE 3 SCS 4.16 5.21 1.82 7.17 8.69 10.89 12.73 14.80 PARKING 02-YI 4 SCS 2.78 3.49 1.22 4.80 5.82 7.29 8.52 9.91 PARKING 03-YI 5 SCS 7.28 9.13 3.18 12.57 15.22 19.08 22.30 25.93 PARKING 04-YI 6 SCS 7.42 10.80 1.15 17.41 22.62 30.29 36.72 43.93 TOWER 0541 7 SCS 11.29 16.45 1.74 26.52 34.44 46.13 55.92 66.90 Other 8 Combine 3, 4, 5, 6 21.55 28.56 7.31 41.92 52.33 67.55 80.28 94.57 Area to Wet and 9 Reservoir 8 0.40 1.85 0.14 10.28 1933. 34.87 45.48 56.51 Wet Pond Route 11 Combine 7,9 11.47 16.66 1.82 26.80 43.29 72.83 93.02 113.67 Post Dev SHWT Two Seasonal High Water Table borings were performed in the proposed wet detention pond; one in the forebay and one in the main pond. These borings showed evidence of the Seasonal High Water Table at 12" and 18" below the existing ground surface. Which yielded an average SHWT elevation of approximately 10.75 feet above mean sea level; included in Appendix 4 are calculations using Darcy's Law for groundwater seepage into the wet detention pond. This calculation shows that the SHWT will not affect the normal pool of the pond significantly (approx. rise of 0.01 feet). Therefore, the proposed normal pool of 10.00 feet should not be affected by the Seasonal High Water Table. However, the pond was also routed with a starting Water Surface Elevation equal to the average SHWT elevation: 10.75. The drawdown orifice was checked to ensure that the drawdown time of the design storm (1.5") was still between 2 and 5 days. Additionally, with the starting water surface of 10.75 the riser rim was adjusted so that the design storm (1.5") could be completely stored above the starting water surface elevation without discharging over the riser rim. These calculations are provided in Appendix 3 with the Hydraflow Hygrograph's analysis. Outlet from Stormwater Basin The wet detention basin outlet's tailwater condition was also considered as part of this analysis. A proposed tail -ditch from the pond outlet at 7.0 to an existing ditch for an existing pond at elevation 3.0 and is approximately 200 linear feet north of the outlet of the pond. The one, ten and one hundred year storm were evaluated in the proposed tail -ditch, and the calculations show that the proposed ditch will be able to carry these flows without impending the proposed outlet of the wet detention basin; please see Appendix 4 for HGL Profiles on the proposed tail -ditch. The tail-ditch's tailwater condition was assumed to be the top of bank of the existing ditch. As can be seen in the above mentioned profiles this tailwater condition does back water up in the proposed tail -ditch but does not affect the outlet from the proposed wet detention basin. CS S T E WA R T September 16, 2008 NCDENR - DWQ Permitting (Wilmington) 127 Cardinal Dr. Wilmington, NC 28405 Re: MICAS New River Maintenance Hangar Wet Pond Seasonal High Water Table Findings; We are submitting this report of findings for the Seasonal High Water Table (SHWT) at the proposed wet pond for the MICAS New River Maintenance Hangar Project. The soil investigation was conducted on September 121" by Stewart Engineering, Inc using a hand auger at the locations attached to determine the soil conditions for the SHWT at the proposed wet pond. The surrounding area is an open field located just north of the air field and adjacent to the existing wet pond. We observed that the field is most likely a fill area and is generally Flat draining west to east. Two borings were made using a hand auger (Bore #1 and Bore #2) to determine the SHWT. Mottling of the soil indicated that the SHWT was found approximately 12" below surface at bore #1 and 18" below at bore #2. Boring Approx. Existing Depth to Approx. Proposed Ground Elevation SHWT Elevation of Normal Pool SHWT #1 12.5 12" 11.5 9.5 #2 11.5 18" 10.0 9.5 Manager Enclosures ENGINEERING. INNOVATION. SOLUTIONS." 421 FAYETTEVILLE STREET RALEIGH. NC T 919.380,8750 SUITE 400 27601 F 919.380,8752 Of rc. STEWART I PULPCIICE PPOTLC u0 - _I CllClll D[SIGNfD DATE �. I ._._-_._.-.....- C14CI(CP DATE .ex LAIOb k-t N'FI.�-A T Y�tckl. Poe � Nc9lA . - � 1 1• Ix 8 ti' ..... - � IZ6 . . . X•T z' . . . • 1Lt rt (I.S• �•01 4S(.' -�� .li �:C�t !t :� ,Sfi C"A .V CI[✓1 .. /SJ / lr J l 7�r578 er 1J.1 �.oG 8 i R'Ssr„-t 7�c%„IS 7 Fri 12/. ?G - .. . . . . . . . . . . .- . FSGI,VEERING.INNOVAiIOtJ. SOLUTIONS.' - .' ` ` `•••"'•••�+N••"Pram GIGE LM CS STEWART FEI'Ex HICL nxPllC� i•O ' ICurN+ IoE $IG NI II - lDAZE C,.r C"E nAEE Z S i It - U I , r+ W b E it It At W w s o = i f, ENGINEEMNG INNOVATION 9OLUIIO•IS AAvaendix 2 2. Site Information a. QUAD Map b. FEMA Map C. Soils Map d. Pre-Dev and Post-Dev Drainage Area Map e. Rainfall Data N 0 0 n 0 i f o n� � O O r (D N O O � 3 O F 3� 0 ' a= to v �N n ax ' Z V Q n • ti my LCCLyW ac o P 3 y W oseP�€� 8 z s, •:�f E Eg ¢n O mCT E L16 x 1Ow e w g#% "Suit a ,s—E E LL C • � E m e•m «& } ?x x. FO 4S 113MON, ri N 1 .. W ' a- 'ksx,.y3N4yNS O wo F x r � a •• i� ''' � ', r Q Au � � M dm W N A ' N O O �. O W W Soil Map-Onslow County, North Carolina MAPLEGEND Area of Interest (A01) Area of Interest (AOI) Solis Soil Map Units Special Point Features Blowout ® Borrow Pit X Clay Spot ♦ Closed Depression Y. Gravel Pit Gravelly Spot © Landfill A Lava Flow ,6 Marsh yt Mine or Quarry ® Miscellaneous Water 0 Perennial Water Rock Outcrop } Saline Spot Sandy Spot Severely Eroded Spot o Sinkhole yt Slide or Slip 0 Sodic Spot Spoil Area Q Stony Spot �n Very Stony Spot Wet Spot Other Special Line Features Gully Short Steep Slope Other Political Features Municipalities 8 Cities OUrban Areas Water Features Oceans �..,. Streams and Canals Transportation Rails Roads �y Interstate Highways US Routes State Highways N Local Roads Other Roads MAP INFORMATION Original soil survey map sheets were prepared at publication scale. Viewing scale and printing scale, however, may vary from the original. Please rely on the bar scale on each map sheet for proper map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http:/Avebsoilsu"ey.nres.usda.gov Coordinate System: UTM Zone 18N This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Onslow County, North Carolina Survey Area Data: Version 10, Mar 21, 2008 Date(s) aerial images were photographed: 1999 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. USDA Natural Resources Web Soil Survey 2.0 6/24/2008 eiaw Conservation Service National Cooperative Soil Survey Page 2 of 3 Soil Map-Onslow County, North Carolina Map Unit Legend Onslow County, North Carolina (NC1133) Map Unit Symbol Map Unit Name Acres In AOI Percent of AOI GpB Goldsboro -Urban land complex, 0 to 5 percent slopes 6.4 83.2% Ur Urban land 1.3 16.8% Totals for Area of Interest (AOI) 7.71 100.0% � Natural Resources Web Soil Survey 2.0 6/24/2008 Conservation Service National Cooperative Soil Survey Page 3 of 3 c Em Bull Al- MM. W LEGEND I (m W) - EOPM �T �A JIL + .AIMT lj KEY PLAN ay LEGEND GRAPHIC SCALE CGOO 1 7 2 3 4 5 GMQIECf MU � IA.6 AC LEGEND ON-SIM DMN< c MG O -SIZE pR E ME 0"-SM DRU E ME M TO PiOIER I»fKn NMwILv Rp5 SOVIx LN.II)3 SF� - 1WS IYP (INCILCED W RiOIER uuus 4 � fxx) - Q61eW SPot OFv11V1 ♦ xx - i�D 9Jl OIVAMN - 4Oi AM1p O _ g61ff0 CO'lIM II96 ® - UIIN BA91 OO - JIXCI4M BS - f1A�ID EIO 4LIYX P5 sNn PR sm - 1F9CN [aW ro sTM 1M rvw wwlsat wu srslw ®STEWART � VNI 134 IF Vi� 2 3 4 NOTES ------ ------ — SEE SNEEr CGIOSA FOR CONTI"TION --------- WAR wr rk LEGEND M.G Wl 10 -.S.m MSmrIsnI[Y -3 KEY PLAN fps L �7 Ai 41— ';1 osTCWART GRAPHIC SCALE 0 w 1. NO �M HAVE SEEN 4 �.M-;90 DENTFIEDONMSVTE 04 Ali CG101 5 i o I ' z cf) I ;II i.l o I I D WET DETENTION BASIN POND CRD sECI S TI I I Y r 61 ea . u..W -.. mar I. msYHe 4 TC An O _ pfNHO [OIIOA lA9R ®-GIdB4V OO _1R[WI BL �( - IUR➢ fIQ 4CIVH ro smr, mm _�1I S j w ; ®TEWART � R® GRAPHIC SCALE mm RSE rvwwa 0 i5' 0W n. pOrvO RSER DETUL m 4 S Precipitation Frequency Data Server Page 1 of 4 POINT PRECIPITATION FREQUENCY ESTIMATES FROM NOAA ATLAS 14 North Carolina 34.543 N 77.456 W 49 feet from "Precipitation -Frequency Atlas of,he United States" NOAA Atlas 14. Volume 2, Version 3 G.M. Bonin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley NOAA, National Weather Scrviee. Silver Spring, Maryland, 2004 Extracted: Fri Jun 27 2008 Confidence Limits Location Maps Other Info. GIS data Maps Help Docs U.S. Map Precipitation Frequency Estimates (inches) AP* E (1-in- 5 min 10 - min IS _ ram 30 - ram 60 - min 120 - min 3 hr 6 hr ❑❑❑❑❑❑ 12 hr 24 hr 48 hr 4 da 7 da 10 da 20 da . 30 da 45 da . 60 da 0.54 0.86 LOS L50 1.88 2.31 2.50 3.05 3.60 4.12 4.76 5.29 6.07 6.69 8.75 10.76 13.49 3:0 0 0.67 1.07 1.35 1.92 2.47 3.12 3.38 4.14 4.91 5.65 6.49 7.13 8.1 I 8.81 11.30 13.72 17.07 20.38 10 0.76 1.21 1.53 2.22 2.89 3.72 4.07 4.98 5.94 6.83 7.83 8.51 9.60 10.34 13. 22 15.77 19.57 23.13 25 0,86 1.37 1.74 2.57 3.43 4.54 5.02 6.16 7.40 8.55 9.78j 10.45 11.68 12,46 15.59 18.46 22.90 26.677 50 0.94 1.49 1.89 2.84 3.85 5.20 5.82 7.16 8.65 9.99 11.45 12.07 13.37 14.178 1Z55 20.54 25.50 29.34 100 1.01 1.61 2E 3.11 4.29 5.91 6.69 EE 10.05 11.61 EE 13.82 15.19 16.02 Efl Efl 28.19 32.074 200 1.09 1.72 2.17 3.38 4.75 6.68 7.64 9.48 11.60 I3.41 15.40 15.73 17.15 17.98 21.80 2 4.88 30.98 34.77 500 1.18 1,87 2.36 3.75 5.38 7.77 9.05 11.28 13.92 16.13 18.56 18.81 20.00 20.81 24.87 27.88 34.84 38.44 1000 1.26 1.99 2.50 4.05 5.91 8.69 10.27 12.83 15.97 18.48 21.30 21.45 22.37 23.14 27.35 30.24 37.90 41.26 These precipitation frequency estimates are based on an annual maxima series AEP is the Annual Exceedance Probability. Please refer to the documentation for more information. NOTE: Formamng forces estimates near zero to appear as zem. * Upper bound of the 90% confidence interval Precipitation h�edsa) Frequencyhr 6a0y 1rara hEstimates �d(ianyc in- ram ram ram �hr d y min day tiny MF 0.58 0.93 1.17 1.62 2.03 2.49 2.70 3.32 3.95 4.53 5.28 5.84 6.65 7.33 9.47 I L55 14.61 I 4:8 0 0.72 1.15 1.46 2.07 2.66 3.36 3.65 4.51 5.38 6.20 7.19 7.86 8.87 9.64 12.23 14.72 18.51 21.94 10 0.81 1.30 1.65 2.39 3.11 4.01 4.39 5.42 6.52 7.48 8.66 9.37 10.49 11.30 14. 77 16.92 21.22 24.77 25 0.92 1.47 1.87 2.77 3.68 4.88 5.40 6.69 8.10 9.34 10.81 11.48 12.71 13.59 16.8T, 9 821 24.86 28.56 50 Lol 1.60 2.03 3.06 4.14 5.59 6.26 7.77 9.44 10.91 12.67 13.23 14.57 15.47 88.94 22.08 27.68 31.43 100 1.09 1.73 2.19 3.35 4.62 6.36 7.19 8.95 10.5 12.66 14.73 15.19 16.57 17.49 21.22 24.41 30.65 34.34 200 1.17 1.86 2.35 3.65 5.12 7.18 8.22 10.27 12.63 14.64 17.09 17.4 18.75 19.69 23.64 26 8 5-- 33.70 37.39 500 L28 2.03 2.55 4.06 5.83 8.38 9.76 12.23 15.19 17.67 20.69 20.83 22.03 22.94 27.16 30.27 38.07 4L56 1000 1.37 2.16 2.71 4.40 6.42 9.40 11.09 13.95 17.44 20.37 23.88 23.94 24.80 25.65 30.01 32.98 41.63 44.86 I he upper bound of me co mdence interval at 90% commence level Is me value *rnch b%of me simulated quanule values tor a given frequency are greater roan. •' These precipitation frequency estimates am based on an annual maxima series AEP is the Annual Exceedance Probability. Please refer to the documentation for more information. NOTE: Formatting prevents estimates near zero to appear as zem. * Lower bound of the 90% confidence interval Precipitation Freauenev Estimates (inches) (l� II 11 II II II I ) 14 II 41 II II 10 II 10 II 30 I 45 ) 60 in[ min m m m n hr hr hrr ay I d vIl Il iay day day day day day 11 2 110.50 110.80 111.01 111.39 111.75 112.15 112.33 112.82 113.28 113.78 114.34 114.82 115.58 116.15 118.11 1110.061112.551115.3011 http://hdsc.nws. noaa.gov/cgi-binlhdsclbuildout.perl?type=pf&units=us&series=am&staten... 6/27/2008 Precipitation Frequency Data Server Page 2 of 4 0 u 0.62 L!L2-d 1.78 2.29 2.89 3.14 3.81 4.47 5.18 5.89 6.48 7.43 8.08 10.45 12.82 15.86 19.09 10 0.70 1.12 1.41 2.05 2.67 3.44 3.76 4.57 5.39 6.24 7.07 7.70 8.76 9.45 12.10 14.70 18.15 21.63 25 0.79 1.26 1.60 2.37 3.15 4.17 4.61 5.62 6.66 7.73 8.76 9.40 10.60 11.33 14.29 17.16 2L13 24.84 50 0.86 1.36 1.73 2.60 3.53 4.75 5.30 6.48 7.73 8.96 00.18 10.78 12.06 12.82 16.00 18.99 EE 27.24 100 0.92 1.47 1.85 2.84 3.91 5.36 6.04 7.41 8.91 10.31 I1.72 12.23 13.58 14.38 17.77 20.86 25.73 29.59 200 0.99 1.56 1.97 3.07 4.30 6.02 6.85 8.41 10. 77 11.76 13.36 13.78 15.19 15.97 19.56 22.70 28.06 31.92 500 1.06 1.68 2.12 3.37 4.83 6.93 8.01 9.87 12.04 13.88 15.78 16.20 17.45 18.24 21.98 25.18 3I.16 34.96 1000 1.12 1.77 2.22 3.60 5.26 7.69 8.98 ILII 13.61 15.66 17.81 18.2I 19.26 20.02 23.93 27.08 33.55 37.26 ' The lower bound of the confidence interval at 90%confidence level Is the value which 5%of the simulated ouandle values for a alven heauencv are less than. - These precipitation frequency estimates are based on an annual maxima aeries AEP is the Annual Exceedance Probability. Please refer to the documentation for more information. NOTE: Formatting prevents estimates near zero to appear as zero. Text version of tables Annual Maxima based Point Precipitation Frequency Estimates - Version: 3 34.543 N 77.456 N 49 ft 42 40 38 36 34 32 30 v 28 S +� 26 a c 24 22 20 m le a 16 14 U a 12 L a. 10 8 6 4 2 0 2 3 4 5 6 7 8 910 20 30 40 50 80 100 140 200 300 500 700 1000 Annual Exoeedanoe Probability (1-in-Y) Fri Jun 27 09:54:47 2008 Duration -min 12U-m -+- - r -x- -Gay -x- 10-min -a- 3-hr -tt- 4-day -+- 45-day � 15-min -r- 6-hr - 7-day 60-day -a- 30-min 12-hr -r- 10-day 60-min -w- 24-hp -e- 20-day -e- http://hdsc. nws.noaa.gov/cgi-bin/hdsc/bui Idout. perl?type=pf&units=us&series=am&staten... 6/27/2008 Precipitation Frequency Data Server Page 3 of 4 0 42 40 38 36 34 32 30 L 28 n 26 oe 24 22 20 18 16 14 0 12 10 a 8 6 4 2 0 Annual Maxima based Point Precipitation Frequency Estimates - Version: 3 34.543 M 77.456 W 49 ft ■ ■ ■ ■ ■ ■III' =��=Nm■�■��■ N d N b m m .+ .- Co d m D4rdt3 on ^ ^ N m V N Fri Jun 27 09:54:47 2008 Maps - Annual xcee ante Probability (l-in-V) n 2 1 in — 1 in 5 1 in 200 -s- 1 in 10 -a- 1 in 500 -+- 1 to 25 t in 1000 -e- t in 50 These maps were produced using a direct map request horn the U,S :Census Bureau Mapping and Cartographic Resources Tiger Map Server. Please read disclaimer! r more inf rmarion. http://hdsc.nws.noaa.gov/cgi-binlhdscfbuildout.perl?type=pf&units=us&series=am&staten... 6/27/2008 Precipitation Frequency Data Server Page 4 of 4 Other Maps/Photographs - LEGEND — State — Connector — County ® Stream 0 Indian Resv Military Area Lake/Pond/Ocean National Park — Street ® Other Park — Expressway City — Highway .0 C_Runty_6 .8 mi Scale 1:228583 12 *average --true scale depends on mon[iitor19res11olution View USCS digital orthophoto quadrangle (DOQ) covering this location from TenmServer; USCS 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 .rites 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 our documentation. Using the National Climatic Data Center's (NCDC station search engine, locate other climate stations within: +/-30:minutes ..,OR... +/_1 degree of this location (34.543/-77.456). Digital ASCII data can be obtained directly from NCDC. Hydrnneleorological Design Studies Center DOCINOAA/National Weather Service 1325 East-West Highway Silver Spring, Me 20910 (301)713-1669 Questions?: HDSC.Questi.r. Qroaa.gov Disclaimer http://hdsc.nws.noaa.gov/cgi-binlhdsc/bui ldout.perl?type=pf&units=us&series=am&statcn... 6/27/2008 Precipitation Frequency Data Server Page 1 of 4 POINT PRECIPITATION '� FREQUENCY ESTIMATES `i' FROM NOAA ATLAS 14 North Carolina 34.543 N 77.456 W 49 feet from "Precipitation -Frequency Atlas of the United States" NOAA Atlas 14. Volume 2, Version 3 G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekm, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland, 2004 Extracted: Toe Jun 24 2008 Confidence Limits - " Location M� ' Other Ind . G1S data M� Heir) ID�II U.S. Mar) Precipitation Intensity Estimates (in/hr) (*60 l F5mi, m n m n m n min min 3 hr 6 hr hr hr. hr 141411 d y d_ay 914 E F2 6.46 5.17 4.34 2.99 1E EE Ej 0.51 0.30 0.17 0.10 0.06 0.04 FO 0-31 0.02 0.01 0.01 0.01 8.02 6.42 5.42 3.85 2.47 1.56 1.13 0.69 0.41 0.24 0.14 0.07 0.05 0.04 0.02 0.02 0.02 0. 11 10 9.08 7.25 6.12 4.43 2.89 1.86 1.35 0.83 0.49 0.28 0.16 0. 99 0.06 0.04 0.03 0.02 0.02 0.02 25 10.33 8.22 6.95 5.15 3.43 2.27 1.67 1.03 0.61 0.36 0.20 0.11 0.07 0.05 0.03 0.03 0.02 0.02 50 11.22 8.93 7.54 5.68 3.85 2.60 1.94 1.20 0.72 0.42 0.24 0.13 0.08 0.06 0.04 0.03 0.02 0.02 100 22.14 9.65 8.13 6.22 4.29 2.9E 2.23 1.38 0.83 0.48 0.28 0.14 0.09 El0.04 0.03 0.03 0.02 200 13.04 10.34 8- 6.77 4.75 3.34 2.55 L58 0.96 0.56 0.32 0.16 0.10 0.07 0.05 0.03 0.03 0.02 500 14.21 11.24 9.43 7.5E 5.38 3.89 3.01 1.88 1.1E 0.67 0.39 0.20 0.1E OF097 0.05 0.04 OF037 0.03 1000 15.17 11.95 10.00 8.09 5.91 4.35 3.42 2.14 1.33 0.77 0.44 0.22 0.13 0.10 0.06 0.04 0.04 0.03 ' These precipitation frequency estimates are based on an annual maxima series AEP is the Annual Exce alanco Probability. Please refer to the documentation for mass information. NOTE: Formatting forces estimates near zero to appear as zero. * Upper bound of the 90% confidence interval Precipitation Intensity Estimates (in/hr) (�IS 30 60 20 30 45 60tra❑m m❑ IEEE[ ❑ ddy F2 6.98 5.59 4.68 3.23 2.03 1.25 0.90 0.55 0.33 0.19 0.11 0.06 0.04 0.03 0.02 0.02 Ej 0. 11 0 8.65 6.92 5.84 4.15 2.66 1.68 L22 0.75 0.45 0.26 0.15 0.08 0.05 0.04 0.03 0.02 0.02 0.02 IO 9.78. 7.82 6.59 4.78 3.11 2.00 1.46 0.90 0.54 0.31 0.18 0.10 0.06 0.05 0.03 0.02 0.02 0.02 25 11.09 R.84 7.47 5.53 3.68 2.44 1.80 1.12 0.67 0.39 0.23 0.12 0.08 0.06 W 0.03 0.02 0.02 50 I2.07 9.62 8.12 6.11 4.14 2.R0 2.08 1.30 0.78 0.45 0.26 0.14 0.09 0.06 0.04 0.03 0.03 0.02 100 13.08 10.39 8.75 6.71 4.62 3.18 2.39 1.49 0.91 0.53 0.31 0.16 0.10 0.07 0.04 0.03 0.03 - 021 200 14.08 11.16 9.39 7.31 5.12 3.59 2.74 1.71 1.05 0.61 0.36 0.18 0.11 0.08 0.05 0.04 0.03 0.03 500 15.39 12.17 10.21 8.13 5.83 4.19 3.25 2.04 1.26 0.74 0.43 0.22 0.13 0.10 0.06 0.04 0.04 0.03 1000 I6.48 12.97 10.86 8.79 6.42 4.70 3.69 2.33 1.45 0.85 0.50 0.25 0.15 0.11 0.06 0.05 0.04 0.03 The upper bound of the confidence interval at 90% confidence level Is die value which 5%of the simulated quantle values for a given frequency are greater than. These precipitation frequency estimates are based on an annual maxima series AEP is the Annual Exceedance Probability. Please refer to the documentation for more information. NOTE: Formatting prevents estimates near zero to appear as zem. * Lower bound of the 90% confidence interval Precipitation Intensity Estimates (in/hr) ra0 IS 30 60 120 ❑❑12 24 48 ❑❑10 30 d4a5y Edy n* [.5in m ddy 61141 4403122781117511108 0079 04770�z710�7009 OS10�17O03 0002 001 0�]1 http://hdsc. nws.noaa.gov/cgi-binihdsclbuildout.perl?type=idf&units=us&series=am&state... 6/24/2008 Precipitation Frequency Data Server Page 2 of 4 10 1 5J 7.44 5.95 1 5.o2 3.57 2.29 1.45 I.OS 0.6 0.37 1 k22J 0.12 0.07 I0.04 I 0.03 0.02 I0.o2 I I0.01 I 0.01 10 8.40 6.71 5.66 4.10 2.67 1.72 1.25 0.76 0.45 0.26 0.15 OF081 OF057 0.04 0.03 0.02 0.02 0.02 25 9.49 7.56 6.39 4.73 3.15 2.08 1.53 0.94 O.EE 0.32 O.IR 0.10 0.06 0.05 0.03 0.02 0.02 0.02 50 10.28 8.19 6.91 5.21 3.53 2.38 1.76 1.08 0.64 0.37 0.21 0.11 0.07 0.05 0.03 0.03 0.0E 0.02 100 11.07 8.79 7.41 5.67 3.91 2.68 2.01 L24 0.74 0.43 0.24 0.13 0.08 0.06 0.04 OA3 0.02 0.02 200 11.83 9.38 7.88 6.14 4.30 3.01 2.28 1.40 0.84 0.49 0.28 0.14 0.09 0.07 0.04 0.03 0.03 0.02 500 12.75 00.09 8.47 6.73 KE 3.47 2.67 1.65 1.00 0.58 0.33 0.17 EE 0.08 0.0E 0.03 0.03 0.02 1000 13.49 10.63 8.90 7.20 E.26 3.84 2.99 1.85 1.13 0.65 0.37 0.19 0.11 0.08 0.05 0.04 0.03 0.03 'The lower bound of the confidence interval at 90%confidene, level is the value which 5%of the simulated nuanfile values for a aiven freauenw are less than. - These precipitation frequency estimates are based on an annual maxima series AEP is the Annual Exceedance Probability. Please refer to the docimentation for more information. NOTE: Formatting prevents estimates near zem to appear as zem. Text version of tables 001 Annual Maxima based Point IDF Curves - Version: 3 34.543 M 77.456 M 49 ft NINE =MM 2 L 0 .1 up Tue Jun 24 08:53:53 2008 Maps - N e N N N N e N S L L L m i i i i i i a a a a a a s a a s ti N M V M V N A Q N 0 0 N Duration n: m o Annual Exceedance Probability (I-in-Y) 2-year 1 0-year - 5-year 200-year -e- 10-year, 500-year 25-year -x- 1000-year -a- 50-uear -o- http://hdsc.nws.noaa.gov/cgi-binlhdscibuildout.perl?type=idf&units=us&series=am&state... 6/24/2008 http://hdsc.nws.noaa.gov/cgi-binlhdscibuildout.perl?type=idf&units=us&series=am&state... 6/24/2008 Precipitation Frequency Data Server Page 3 of 4 t 2o^'w » o"w I on-w an"w no`"w 70114 These maps were produced using a direct map redness from the U.S. Census Bureau Mapping and Canographic Resources Tiger Map Server. Please reed dsrle.....rfar more Informnriun. LEGEND --- State — Connector - County Min Stream Indian Resv Military Area Lake/Pond/Ocean National Park Street poe Other Park — Expressway City —Highway 0 f---, Cgunty6 B Scale 1:220503 1. mt 2 B11 *average --true scale depends on monitor resolution Other Maps/Photographs - View USGS digital orthophoto quadrangle (DOQ) covering this location from TerraServer; 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 - I in(] the 1b'atershed for this location using the U.S. Environmental Protection Agency's site. Climate Data Sources - Precipitation fi-equener re.vultc are based on darn fto n a varieb, of sources, but largely NCDC. The following links provide general infornrntiun about observing .cites in the area, regardless c/if their data was used in this .study. For deviled information ahout the stations used in this .study, please refer to our tlafnmentation. Using the National Climatic Data Center's (NCDC) station search engine, locate other climate stations within: http://hdsc. nws. noaa. gov/cgi-binlhdsc/bui ldout. perl?type=idf&units=us&series=ain&state... 6/24/2008 Appendix 3 3. Hydraulic Calculations I a. 10 Year & 25 Year HGL Profiles - StormCAD b. Peak Flow Analysis - HYDRAFLOW Start Node Stop Node Elevation Ground Startft Elevation Ground (Stop)ft Invert (Upstream) ft Invert (Downstream) ft Length ft () Diameter i ( n ) Material Slope (Calculated) % Flow (ft, /s) Velocity (Average) ft/s 02-YI 01-FES 16.65 12.00 11.62 10.18 286 30 RCP 0.50 32.80 6.68 03-YI 02-YI 16.50 16.65 11.85 11.62 45 30 RCP 0.51 30.07 6.80 04-YI 03-YI 16.53 16.50 13.22 11.85 275 30 RCP 0.50 23.71 6.58 05-MH 04-YI 17.00 16.53 14.21 13.22 198 24 RCP 0.50 17.34 5.52 06-MH 05-MH 17.17 17.00 14.54 14.21 67 24 RCP 0.49 17.46 5.56 07-MH 06-MH 18.25 17.17 14.84 14.54 60 24 RCP 0.50 13.96 5.74 08-MH 07-MH 18.00 18.25 15.50 14.84 133 18 RCP 0.50 6.33 3.58 10-MH 07-MH 19.70 18.25 17.70 15.25 427 18 RCP 0.57 8.29 5.11 09-FES 06-MH 16.75 17.17 14.92 14.54 75 18 RCP 0.51 3.77 2.14 11-FES 05-MH 16.00 17.00 14.71 14.21 100 12 RCP 0.50 0.00 0.00 21-MH 20-FES 14.00 15.00 10.14 10.00 25 24 RCP 0.56 5.31 4.77 22-MH 21-MH 17.00 14.00 10.80 10.14 123 24 RCP 0.54 5.39 4.71 23-MH 22-MH 15.00 17.00 12.32 10.80 229 15 RCP 0.66 5.51 5.81 24-YI 23-MH 17.00 15.00 12.84 12.32 104 15 RCP 0.50 3.36 5.24 25-CB 24-YI 18.75 17.00 13.40 12.84 113 15 RCP 0.50 3.40 5.54 31-FES 30-FES 17.00 17.00 14.52 14.15 71 15 CL IV IRCP 0.52 2.70 3.38 51-RI 50-FES 1 12.00 1 11.00 1 7.50 1 7.00 1 34 1 24 1 RCP 1 1.47 5.10 6.68 k| IF!. A t2 �2 t2 �2 t2 t2 �2 t� :t :t U uo!12-13 ■ U0112AG13 8 9 \'\;��: \\\���� ��/\\\ \�\\\\� 6 (q) U0110"13 J F F I I F ii iL p F II .... .... ... .... .... . (1j) UOIJOAD13 i Elevation (ft) 9 Z� Profile -2 -25YR FLZW 07J ........... . -- ---- ..... ... . . T ... . . . . ... . ........ . -1 1 - I -.1--l-I -1--l-, is - 178 - 17.6 - 17.4- - 17.2 - 17 16.8 16.6 16.4 16,2 Is 15.8- ".6, 5,4- 5, I 14 4 7 1 C 6 Ib 20 30 40 W SiO 76 86 90 im 110 Im 31 LOB 11 107 to S6S 72 15.91 1825 1181 ... .... .... ... .... 33 1 06A 17.17 14.54 --------- -- -- 193 EOL E 8 �2 (11) UOjjRA8j3 Profile ^4^26YR calm Basen ,ou- 1/�5 EGL,,|-U' - '~-- ' ------�---��--------�---� �-----�-------�---- 1s m `» ,z, D. ,z vs « .� ,o m F4 F r Table of Contents Hydraflow Hydrographs by Intelisolve W etpond_20080922.gpw Tuesday, Oct 7 2008, 3:47 PM Hydrograph Return Period Recap............................................................................ 1 1 - Year ' Summary Report ..... Hydrograph Reports Hydrograph No. 1, Hydrograph No. 3, Hydrograph No. 4, Hydrograph No. 5, Hydrograph No. 6, Hydrograph No. 7, Hydrograph No. 8, ................................................................................................................. SCSRunoff, PRE..................................................................................... SCS Runoff, PARKING (02-YI)................................................................ SCS Runoff, PARKING (03-YI)................................................................ SCS Runoff, PARKING (04-YI)................................................................ SCS Runoff, TOWER (05-YI)................................................................... SCSRunoff, Other................................................................................... Combine, Area to WetPond..................................................................... 2 3 3 4 5 6 7 8 9 Hydrograph No. 9, Reservoir, Wet Pond Route.................................................................... 10 PondReport ..................................................................................................................... 11 Hydrograph No. 11, Combine, Post Dev.............................................................................. 12 iydrograph Return Period Recap Hyd. Hydrograph Inflow Peak Outflow(cfs) Hydrograph No. type Hyd(s) description (origin) 1-Yr 2-Yr 3-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr 1 SCS Runoff 14.77 21.58 2.28 34.89 45.39 60.78 73.65 88.09 PRE 3 SCS Runoff 4.16 5.21 1.82 7.17 8.69 10.89 12.73 14.80 PARKING (02-YI) 4 SCS Runoff 2.78 3.49 1.22 4.80 5.82 7.29 8.52 9.91 PARKING (03-YI) 5 SCS Runoff 7.28 9.13 3.18 12.57 15.22 19.08 22.30 25.93 PARKING (04-YI) 6 SCS Runoff -- 7.42 10.80 1.15 17.41 22.62 30.29 36.72 43.93 TOWER (05-YI) 7 SCS Runoff 11.29 16.45 1.74 26.52 34.44 46.13 55.92 66.90 Other 8, Combine 3, 4, 5, 6, 21.55 28.56 7.31 41.92 52.33 67.55 80.28 94.57 Area to WetPond 9 Reservoir 8 0.40 1.85 0.14 10.28 19.23 29.16 38.36 49.38 Wet Pond Route 11 Combine 7, 9, 11.47 16.66 1.82 26.80 43.29 72.83 93.02 113.67 Post Dev Proj. file: Wetpond_20080922.gpw Tuesday, Oct 7 2008, 3:46 PM iydrograph Summary Report Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time Interval (min) Time to peak (min) Volume (cult) Inflow hyd(s) Maximum elevation (ft) Maximum storage (cuft) Hydrograph description 1 SCS Runoff 14.77 1 729 56,082 — -- PRE 3 SCS Runoff 4.16 1 724 14,386 — PARKING (02-YI) 4 SCS Runoff 2.78 1 724 9,633 — PARKING (03-YI) 5 SCS Runoff 7.28 1 724 25,214 — PARKING (04-YI) 6 SCS Runoff 7.42 1 725 22,992 — TOWER (05-YI) 7 SCS Runoff 11.29 1 725 35,008 — -- Other 8 Combine 21.55 1 724 72,225 3, 4, 5, 6, Area to WetPond 9 Reservoir 0.40 1 1089 34,728 8 11.41 58,741 Wet Pond Route 11 Combine 11.47 1 725 69,735 7, 9, Post Dev Wetpond_20080922.gpw Return Period: 1 Year Tuesday, Oct 7 2008, 3:46 PM Hydrograph Plot Hydraflow Hydrographs by Intelisolve Hyd. No. 1 PRE Hydrograph type = SCS Runoff Storm frequency = 1 yrs Drainage area = 10.610 ac Basin Slope = 0.5 % Tc method = KIRPICH Total precip. = 3.30 in Storm duration = 24 hrs Q (cfs) 15.00 12.00 9.00 6.00 3.00 000 Tuesday, Oct 7 2008, 3:46 PM Peak discharge = 14.77 cfs Time interval = 1 min Curve number = 80 Hydraulic length = 1000 ft Time of conc. (Tc) = 12.25 min Distribution = Type III Shape factor = 484 Hydrograph Volume = 56,082 cuft PRE Hyd. No. 1 — 1 Yr 0 2 5 7 9 12 14 16 19 21 23 26 — Hyd No. 1 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Inlelisolve Tuesday, Oct 7 2008, 3:46 PM Hyd. No. 3 PARKING (02-YI) Hydrograph type = SCS Runoff Peak discharge = 4.16 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 1.253 ac Curve number = 98 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume = 14,386 cult PARKING (02-YI) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:46 PM Hyd. No. 4 PARKING (03-YI) Hydrograph type = SCS Runoff Peak discharge = 2.78 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 0.839 ac Curve number = 98 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 PARKING (03-YI) Q (cfs) Hyd. No. 4 — 1 Yr 3.00 191I1111 W Hydrograph Volume = 9,633 cuR Q (cfs) 3.00 WA1I11 1.00 EMW 0.0 2.3 4.7 7.0 9.3 11.7 14.0 16.3 18.7 21.0 23.3 — Hyd No. 4 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:46 PM Hyd. No. 5 PARKING (04-YI) Hydrograph type = SCS Runoff Peak discharge = 7.28 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 2.196 ac Curve number = 98 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 Q (cfs) 8.00 CX4I11I 2.00 2.3 Hyd No. 5 4.7 7.0 PARKING (04-YI) Hyd. No. 5 -- 1 Yr Hydrograph Volume = 25,214 cuft Q (cfs) 8.00 4.00 2.00 i 1 ' 0.00 9.3 11.7 14.0 16.3 18.7 21.0 23.3 Time (hrs) Hydrograph Plot HydraBow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:46 PM Hyd. No. 6 TOWER (05-YI) Hydrograph type = SCS Runoff Peak discharge = 7.42 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 4.152 ac Curve number = 80 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 Q (cfs) 8.00 . M 4.00 NM 2 5 Hyd No. 6 7 TOWER (05-YI) Hyd. No. 6 — 1 Yr Hydrograph Volume = 22,992 cult Q (cfs) 8.00 4.00 2.00 - 0.00 9 12 14 16 19 21 23 26 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:47 PM Hyd. No. 7 Other Hydrograph type = SCS Runoff Peak discharge = 11.29 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 6.322 ac Curve number = 80 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of cone. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 Q (cfs) 12.00 10.00 E:10I111 11111111111MIll 4.00 2.00 Emmons Other Hyd. No. 7 -- 1 Yr Hydrograph Volume = 35,008 tuft Q (cfs) 12.00 10.00 8.00 6.00 4.00 2.00 11MR0 0 2 5 7 9 12 14 16 19 21 23 26 Time (hrs) — Hyd No. 7 Hydrograph Plot Hydraflow Hydrographs by IMelisolve Tuesday, Oct 7 2008, 3:47 PM Hyd. No. 8 Area to WetPond Hydrograph type = Combine Peak discharge = 21.55 cfs Storm frequency = 1 yrs Time interval = 1 min Inflow hyds. = 3, 4, 5, 6 Hydrograph Volume = 72,225 cult Area to WetPond Hydrograph Plot Hydraflow Hydrographs by Inlelisolve Tuesday, Oct 7 2008, 3:47 PM Hyd. No. 9 Wet Pond Route Hydrograph type = Reservoir Peak discharge = 0.40 cfs Storm frequency = 1 yrs Time interval = 1 min Inflow hyd. No. = 8 Max. Elevation = 11.41 ft Reservoir name = Wet Pond Max. Storage = 58,741 cuft Storage Indication method used. Q (cfs) 24.00 20.00 16.00 12.00 4.00 Wet Pond Route Hyd. No. 9 — 1 Yr Hydrograph Volume = 34,728 cult Q (cfs) 24.00 20.00 16.00 12.00 4.00 0.00 -' — r L 0.00 0 5 10 15 19 24 29 34 39 44 48 Time (hrs) — Hyd No. 9 —Hyd No. 8 Pond Report Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:47 PM Pond No. 1 - Wet Pond Pond Data Pond storage is based on known contour areas. Average end area method used. Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 10.00 36,797 0 0 1.00 11.00 43,570 40,184 40,184 2.00 12.00 46,785 45,178 85,361 3.00 13.00 50,057 48,421 133,782 3.50 13.50 51,714 25,443 159,225 Culvert / Orifice Structures Weir Structures [A] [BI [C] [D] [A] [B] [C] [D] Rise (In) = 24.00 3.00 0.00 0.00 Crest Len (ft) = 12.00 20.00 0.00 0.00 Span (in) = 24.00 3.00 0.00 0.00 Crest El. (ft) = 11.40 12.25 0.00 0.00 No. Barrels = 1 1 - 0 0 Weir Coeff. = 3.33 2.60 0.00 0.00 Invert El. (ft) = 7.50 10.00 0.00 0.00 Welr Type = Riser Broad -- - Length (ft) = 30.00 1.00 0.00 0.00 Multi -Stage = Yes No No No Slope (%) = 1.00 1.00 0.00 0.00 N-Value = .013 .013 .000 .000 Orif. Coeff. = 0.60 0.60 0.00 0.00 Multi -Stage = n/a Yes No No Exflltratlon = 0.000 in/hr (Contour) Tailwater Elev. = 0.00 ft Note: CuN 410nrice euNows have Seen analyzed under inlet and meet central. Stage (it) Stage / Discharge Stage (it) 4.00 4.00 3.00 3.00 2.00 I 2.00 1.00 1.00 0.00 0.00 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00 100.00 110.00 Discharge (cfs) - Total O Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:47 PM Hyd. No. 11 Post Dev Hydrograph type = Combine Peak discharge = 11.47 cfs Storm frequency = 1 yrs Time interval = 1 min Inflow hyds. = 7, 9 Q (cfs) 12.00 10.00 M AM 4.00 2.00 Post Dev Hyd. No. 11 -- 1 Yr Hydrograph Volume = 69,735 cuff Q (cfs) 12.00 10.00 4.00 WA1I11 0.00 1 ' 1 - ) ' I ' 0.00 0 5 10 15 19 24 29 34 39 44 48 Time (hrs) — Hyd No. 11 —Hyd No. 7 —Hyd No. 9 Table of Contents Hydrallow Hydrographs by Intelisolve W etpond_20080922.gpw Tuesday, Oct 7 2008, 3:44 PM Hydrograph Return Period Recap............................................................................ 1 1 -Year SummaryReport ....................................................................................................................... Hydrograph Reports ................... Hydrograph No. 1, SCS Runoff, Hydrograph No. 3, SCS Runoff, Hydrograph No. 4, SCS Runoff, Hydrograph No. 5, SCS Runoff, Hydrograph No. 6, SCS Runoff, Hydrograph No. 7, SCS Runoff, Hydrograph No. 8, Combine, Area to WetPond Hydrograph No. 9, Reservoir, Wet Pond Route Pond Report 2 3 3 4 5 6 7 8 .9 10 11 ..................................................................................................................... Hydrograph No. 11, Combine, Post Dev.............................................................................. 12 iydrograph Return Period Recap Hyd. Hydrograph Inflow Peak Outflow (cfs) Hydrograph No. type Hyd(s) description (origin) 1-Yr 2-Yr 3-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr 1 SCS Runoff -- 14.77 21.58 2.28 34.89 45.39 60.78 73.65 88.09 PRE 3 SCS Runoff 4.16 5.21 1.82 7.17 8.69 10.89 12.73 14.80 PARKING (02-YI) 4 SCS Runoff -- 2.78 3.49 1.22 4.80 5.82 7.29 8.52 9.91 PARKING (03-YI) 5 SCS Runoff 7.28 9.13 3.18 12.57 15.22 19.08 22.30 25.93 PARKING (04-YI) 6 SCS Runoff 7.42 10.80 1.15 17.41 22.62 30.29 36.72 43.93 TOWER (05-YI) 7 SCS Runoff 11.29 16.45 1.74 26.52 34.44 46A3 55.92 66.90 Other 8 Combine 3, 4, 5, 6, 21.55 28.56 7.31 41.92 52.33 67.55 80.28 94.57 Area to WetPond 9 Reservoir 8 4.50 9.52 0.13 20.36 26.59 32.71 40.35 50.13 Wet Pond Route 11 Combine 7, 9, 11.47 16.66 1.82 26.80 43.29 72.83 93.02 113.67 Post Dev Proj. file: Wetpond_20080922.gpw Tuesday, Oct 7 2008, 3:43 PM iydrograph Summary Report Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time Interval (min) Time to peak (min) Volume (cult) Inflow hyd(s) Maximum elevation (ft) Maximum storage (cuft) Hydrograph description 1 SCS Runoff 14.77 1 729 56,082 — PRE 3 SCS Runoff 4.16 1 724 14,386 — PARKING (02-YI) 4 SCS Runoff 2.78 1 724 9,633 — PARKING (03-YI) 5 SCS Runoff 7.28 1 724 25,214 — PARKING (04-YI) 6 SCS Runoff 7.42 1 725 22,992 — -- -- TOWER (05-YI) 7 SCS Runoff 11.29 1 725 35.008 — Other 8 Combine 21.55 1 724 72,225 3, 4, 5, 6, Area to WetPond 9 Reservoir 4.50 1 750 55,646 8 11.62 38,994 Wet Pond Route 11 Combine 11.47 1 725 69,735 7, 9, Post Dev Wetpond_20080922.gpw Return Period: 1 Year Tuesday, Oct 7 2008, 3:43 PM Hydrograph Plot HydraFlow Hydrographs by Intelisolve Hyd. No. 1 PRE Hydrograph type = SCS Runoff Storm frequency = 1 yrs Drainage area = 10.610 ac Basin Slope = 0.5 % Tc method = KIRPICH Total precip. = 3.30 in Storm duration = 24 hrs Q (cfs) 15.00 12.00 3.00 yir� PRE Hyd. No. 1 -- 1 Yr Tuesday, Oct 7 2008, 3:43 PM Peak discharge = 14.77 cfs Time interval = 1 min Curve number = 80 Hydraulic length = 1000 ft Time of conc. (Tc) = 12.25 min Distribution = Type III Shape factor = 484 Hydrograph Volume = 56,082 cult Q (cfs) 15.00 12.00 • 1# 3.00 Now 0 2 5 7 9 12 14 16 19 21 23 26 — Hyd No. 1 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:43 PM Hyd. No. 3 PARKING (02-YI) Hydrograph type = SCS Runoff Peak discharge = 4.16 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 1.253 ac Curve number = 98 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 PARKING (02-YI) Q (cfs) Hyd. No. 3 -- 1 Yr 5.00 , 4.00 3.00 2.00 1.00 W1111 Hydrograph Volume = 14,386 cuff Q (cfs) 5.00 4.00 3.00 2.00 1.00 0.0 2.3 4.7 7.0 9.3 11.7 14.0 16.3 18.7 21.0 23.3 — Hyd No. 3 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Hyd. No. 4 PARKING (03-YI) Hydrograph type = SCS Runoff Storm frequency = 1 yrs Drainage area = 0.839 ac Basin Slope = 0.0 % Tc method = USER Total precip. = 3.30 in Storm duration = 24 hrs Q (cfs) 3.00 KI 1.00 rTaTa� PARKING (03-YI) Hyd. No. 4 — 1 Yr Tuesday, Oct 7 2008, 3:43 PM Peak discharge = 2.78 cfs Time interval = 1 min Curve number = 98 Hydraulic length = Oft Time of conc. (Tc) = 5.00 min Distribution = Type III Shape factor = 484 Hydrograph Volume = 9,633 cult Q (cfs) 3.00 2.00 1.00 Mww 0.0 2.3 4.7 7.0 9.3 11.7 14.0 16.3 18.7 21.0 23.3 — Hyd No. 4 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:43 PM Hyd. No. 5 PARKING (04-YI) Hydrograph type = SCS Runoff Peak discharge = 7.28 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 2.196 ac Curve number = 98 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume = 25,214 cuft PARKING (04-YI) Q (cfs) Hyd. No. 5 — 1 Yr Q (cfs) 8.00 8.00 6.00 6.00 4.00 4.00 2.00 - — - 2.00 0.00 - 0.00 0.0 2.3 4.7 7.0 9.3 11.7 14.0 16.3 18.7 21.0 23.3 Time (hrs) — Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Inlelisolve Tuesday, Oct 2008, 3:43 PM Hyd. No. 6 TOWER (05-YI) Hydrograph type = SCS Runoff Peak discharge = 7.42 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 4.152 ac Curve number = 80 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 Q (cfs) 8.00 .IM 4.00 2.00 0.00 1 11 0 2 5 — Hyd No. 6 Hydrograph Volume = 22,992 cult TOWER (05-YI) Hyd. No. 6 -- 1 Yr 7 9 12 14 16 19 21 Q (cfs) 8.00 CX1U1 2.00 - 0.00 23 26 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:43 PM Hyd. No. 7 Other Hydrograph type = SCS Runoff Peak discharge = 11.29 cfs Storm frequency = 1 yrs Time interval = 1 min Drainage area = 6.322 ac Curve number = 80 Basin Slope = 0.0 % Hydraulic length = Oft Tc method = USER Time of conc. (Tc) = 5.00 min Total precip. = 3.30 in Distribution = Type III Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume = 35,008 cult Other Q (cfs) Hyd. No. 7 -- 1 Yr Q (cfs) 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 - 4.00 2.00 — 2.00 000 - 0 00 0 2 5 7 9 12 14 16 19 21 23 26 — Hyd No. 7 Time (hrs) Hydrograph Plot Hydrallow Hydrographs by Intellsolve Tuesday, Oct 7 2008, 3:43 PM Hyd. No. 8 Area to WetPond Hydrograph type = Combine Peak discharge = 21.55 cfs Storm frequency = 1 yrs Time interval = 1 min Inflow hyds. = 3, 4, 5, 6 Hydrograph Volume = 72,225 cult Area to WetPond Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:44 PM Hyd. No. 9 Wet Pond Route Hydrograph type = Reservoir Peak discharge = 4.50 cfs Storm frequency = 1 yrs Time interval = 1 min Inflow hyd. No. = 8 Max. Elevation = 11.62 ft Reservoir name = Wet Pond @ 10.75 Max. Storage = 38,994 cuft Storage Indication method used. Q (Cfs) 24.00 WzOISIO t 16.00 12.00 ie 4.00 Hydrograph Volume = 55,646 cult Q (cfs) 24.00 20.00 16.00 12.00 EMU, 4.00 0.00 -' — ' l 0.00 0 5 10 15 19 24 29 34 39 44 48 Time (hrs) — Hyd No. 9 —Hyd No. 8 Pond Report Hydratlow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:44 PM Pond No. 2 - Wet Pond @ 10.75 Pond Data Pond storage is based on known contour areas. Average end area method used. Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sgft) Incr. Storage (cuft) Total storage (cuft) 0.00 10.75 42,774 0 0 0.25 11.00 43,570 10,793 10,793 1.25 12.00 46,785 45,178 55,971 2.25 13.00 50,057 48,421 104,392 2.75 13.50 51,714 25,443 129,834 Culvert / Orifice Structures [A] [B] [C] [D] Rise (in) = 24.00 3.00 0.00 0.00 Span (in) = 24.00 3.00 0.00 0.00 No. Barrels = 1 1 0 0 Invert El. (ft) = 7.50 10.75 0.00 0.00 Length (ft) = 30.00 1.00 0.00 0.00 Slope (%) = 1.00 1.00 0.00 0.00 N•Value = .013 .013 .000 .000 Dint. Coeff. = 0.60 0.60 0.00 0.00 Multistage = Na Yes No No Stage (ft) 3.00 2.00 fir➢1 Weir Structures [A] Crest Len (ft) = 12.00 Crest El. (ft) = 11.40 Weir Coeff. = 3.33 Weir Type = Riser Multistage = Yes [B] [C] [D] 20.00 0.00 0.00 12.25 0.00 0.00 2.60 0.00 0.00 Broad - - No No No Exflltration = 0.000 inthr (Contour) Tailwater Elev. = 0.00 it Note: CulvorlfOntlee outflows have boon analyzed under inlet and outlet control. Stage / Discharge Stage (ft) 3.00 2.00 1.00 000 WbTbTS� 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00 100.00 110.00 Discharge (cis) - Total O Hydrograph Plot Hydraflow Hydrographs by Intelisolve Tuesday, Oct 7 2008, 3:44 PM Hyd. No. 11 Post Dev Hydrograph type = Combine Peak discharge = 11.47 cfs Storm frequency = 1 yrs Time interval = 1 min Inflow hyds. = 7, 9 Q (cfs) 12.00 10.00 8.00 6.00 4.00 2.00 000 Hydrograph Volume = 69,735 cult Post Dev Hyd. No. 11 -- 1 Yr 0 5 10 15 19 24 29 34 39 44 48 V VV Time (hrs) — Hyd No. 11 —Hyd No. 7 —Hyd No. 9 Appendix 4 4. Hydraulic Calculations II a. Pollutant Calculations b. BMP Supplemental Form i. Wetpond Basin ii. Filter Strip b. Dissipater Calculations C. Buoyancy Check e. Ditch Flow at Pond Outlet STEWART Wet Detention Pond Sizing - WETPOND A (for 90% TSS removal) Project: MCAS New River Hangar Number: C8020 Date: 28-Oct-08 Required Surface Area Re uired Storage for 1st 1.5" of runoff Total Drainage Area = 8.43 ac Simple Method Total Impervious Area = 4.10 ac Percent Impervious = 49% Rv = 0.05 + 0.009(I) Design Rainfall Depth = 1.5 in I = % impervious = 49% Max. Perm. Pool Depth = 3 ft SA/DA Ratio = 5.60 Rv = 0.49 in Surface Area Required = 20552 sf Volume = 22408 cf — 0.47 ac Calculation Methods are taken from DEHNR Stormwater Best Management Practices Manual, Latest Version Surface Area Provided at Normal Pool = 36797 sf Temporary Volume Provided = 22583 cf 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com STEWART Stage -Storage Anaylsis - Pond A (Above Normal Pool Only) Contour ft) Area (ft2) Incr Vol (ft3 Accum Vol ft3 Stage Z ft In S In Z Zest 10 36797 0 0 0 10.5 41983 19695 19695 0.5 9.8881 -0.693 0.5029 11 43570 21388 41083 1 10.623 0 0.9955 12 1 467851 451781 86261 1 2 111.365 0.6931 1.9825 13 1 50057 148421 134682 3 111.811 1.0986 2.9985 13.75 1 517141 38164 11728461 3.75 1 12.06 1.3218 3.7804 Intercept = 10.6283 b = 1.08 R sq = 0.9999 Ks = 41284.9 41 0- a 1.0768x + 10.628 s -1 -0.5 0 0.5 1 1.5 421 Fayetteville St., Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com Q STEWART Volume Calculations - Pond A Forebay Bottom Elev = 5 ft Forebay Berm Elev = 10 ft Main Pond Bottom Elev = 5 ft Bottom Of Veg. Shelf Elev = 9.5 ft Normal Pool Elev = 10 ft Top Of Veg. Shelf Elev = 10.5 R Top of Dam Elev = 13.75 ft Forebav Volume Contour k Area (ft2) Incr Vol (R3) Accum Vol ft3 5 2700 0 0 6 3460 0 0 7 4270 3865 3865 8 5150 4710 8575 9 6080 5615 14190 9.5 6560 3160 17350 10 8020 3645 20995 Pond Volume Contour (ft) Area (ft2) Incr Vol R3) Accum Vol (R3 5 13415 0 0 6 15680 0 0 7 18000 16840 16840 8 20380 19190 36030 9 22800 21590 57620 9.5 24050 11713 69333 10 1 27800 12963 82295 Volume above Normal Pool Contour R Area 112 Incr Vol R3 Accum Vol R3 10 36797 0 0 10.5 41983 19695 19695 11 43570 21388 41083 12 46785 45176 86261 13 50057 48421 134682 13.75 51714 38164 172846 Bottom Of Pond Area = 15680 sq ft Bottom Of Veg. Shelf Area = 31768 sq ft Normal Pool Area = 36797 sq ft Top of Veg. Shelf Area = 41983 sq ft Design Storm (routed 10.48') = 41770 sq ft Temporary Pool (next outlet 11.4') = 44850 sq ft Dav OP1 2.81 (Total Vol / Normal Pool) av OP2 3.45 Forbay Vol (NP) = 20995 Fd_ / l j'/ \ / Total Vol (NP)= 103290 A^^�A°°�2A^°�0.25x '+ /IJ+LI` JJ Forebay equals 20.3% of total volume. x�-I� m r ((( 31768ft2 ji,2 +1568ofti loft-6ftd=o.25x(1+797ft')]+[(31768 )x(31,768jt2) 2 r_�x C� + 317(,S� � 31?to8 -f15� \L_J 3Gl4 7 ;L 31 �6a a37)y J, q? -} y 3_5 '51,G7 (0 1 ; 3.0' 421 Fayetteville St., Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewan-eng.com STEWART Volume Calculations - Pond A Forebay Bottom Elev = 5 ft Forebay Berm Elev = 10 ft Main Pond Bottom Elev = 5 ft Bottom Of Veg. Shelf Elev = 9.S ft Normal Pool Elev = 10 ft Top Of Veg. Shelf Elev = 10.5 ft Top of Dam Elev = 13.75 ft Forebay Volume Contour ft Area ft2 Incr Vol ft3 Accum Vol ft3 5 2700 0 0 6 3460 0 0 7 4270 3865 3865 8 5150 4710 8575 9 6080 5615 14190 9.5 6560 3160 17350 10 8020 3645 20995 Pond Volume Contour ft Area ft2 Incr Vol ft3 Accum Vol ft3 5 13415 0 0 6 15680 0 0 7 18000 16840 16840 8 20380 19190 36030 9 22800 21590 57620 9.5 24050 11713 69333 10 27800 1 182295 Forbay Vol(NP) = 20995 Total Vol (NP)= 103290 Volume above Normal Pool Contour ft Area ft2 Incr Vol ft3 Accum Vol ft3 10 36797 0 0 10.5 41983 19695 19695 11 43570 21388 41083 11.4 44850 17684 58767 12 46785 27491 86258 13 50057 48421 134679 13.75 5171438164 172843 Bottom Of Pond Area = 15680 sq ft Bottom Of Veg. Shelf Area = 31768 sq ft Normal Pool Area = 36797 sq ft Top of Veg. Shelf Area = 41983 sq ft Design Storm (routed 10.48') = 41770 sq ft Temporary Pool (next outlet 11.4') = 44850 sq ft Forebay equals 20.3% of total volume. Dav OPI Fav OP2 NOV 1 2 2008 2.81 (Total Vol / Normal Pool) 3.08 d,,,, = 31768 2 ][3l768t2 0.25 x 1 +'fr+f [ ( +15680 t2 x ( ) (31,768 36797 ft2) 2 ft2 421 Fayetteville St., Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 w .stewart-eng.com S STEWART RE NOV 1 2 2008 BY: Water Quality Drawdown Calculation - Pond A (1st 1.5inch of rainfall) Characteristics Total Drainage Area = 8.425207 ac Pond Invert = 7.00 ft Total Impervious Area = 4.104545 ac Normal Pool Elevation = 10.00 ft Percent Impervious = 49% Next Structure El. = 11.40 ft Storage Depth = 1.40 ft Rv = 0.05 + 0.009(I) Average Head (1-1/3) = 0.47 ft I = % impervious = 49% Ks = 41213 Rv = 0.49 in b= 1.08 Minimum depth Runoff Vol. = 22408 cf required for storage = 0.57 ft Find orfice size for 2-day drawdown time Flow Rate = Volume (cf) / Time (sec) 0.1297 cfs Q=Cp*A*(2*g*h)A(1/2) (Orifice Equation - solve for A (area)) A= 0.03942 ft' 5.67709 in Orfice Size 2 day) = 2.69 in dia Find orfice size for 5-day drawdown time Flow Rate = Volume (cf) / Time (sec) = 0.0519 cfs Q=Co*A*(2*g*h)A(1/2) (Orfice Equation - solve for A (area)) A= 0.01577 ft' 2.27084 in Orfice Size 5 day) = 1.70 in dia Select orfice size between 2 and 5 day size Size selected = 2 " dia Actual Drawdown Time Volume = 22408 cf Pipe Size = 2 "dia Area = 0.021817 ftZ Flow Rate = 0.07176 cfs Drawdown Time = 3.61 days NOTE - Drawdown calculated using the head to the next outlet with the area for the design sto m. 421 Fayetteville St., Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com 1 11 STEWART Project Project No. Outlet ID RIPRAP OUTLET PROTECTION WORKSHEET MCAS New River Hangar C8020 O1-FES Outlet flowrate 32.81 cfs Pipe diameter 30 inches Outlet pipe slope 0.52 percent Full flow velocity 6.7 ft/sec Date 18-Jul-08 Designer JWP l t 1 Zone from graph above = 2 Outlet pipe diameter 30 in. Outlet flowrate 32.8 cfs Outlet velocity 6.7 ft/sec Material = Class B Length = 15.0 ft. Width = 7.5 ft. Stone diameter = 6 in. Thickness= 22 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class 1 13 22 8 x D(o) 3 x D(o) 4 Class 1 13 22 8 x D(o) 3 x D(o) 5 Class 11 23 27 10 x D(o) 3 x D(o) 6 Class 11 23 27 10 x D(o) 3 x D(o) 7 Special study required Calculations based on NY DOT method - Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com 0 STEWART Project Project No. Outlet ID RIPRAP OUTLET PROTECTION WORKSHEET MCAS New River Ilangar C8020 20-FES Outlet flowrate 5.29 cfs Pipe diameter 24 inches Outlet pipe slope 0.56 percent Full flow velocity 1.7 ft/sec Date 18-Jul-08 Designer JWP I. WOMEN OE = w� �wriravc�-- t t Zone from graph above = Outlet pipe diameter 24 in. Outlet flowrate 5.3 cfs Outlet velocity 1.7 ft/sec Material = Class A Length = 8.0 ft. Width = 6.0 ft. Stone diameter = 3 in. Thickness = 9 in. Zone Material Diameter I Thickness Length Width I Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class 1 13 22 8 x D(o) 3 x D(o) 4 Class 1 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study required Calculations based on NY DOT method - Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com T! STEWART RIPRAP OUTLET PROTECTION WORKSHEET Project MCAS New River Hangar Project No. C8020 Outlet ID 30-FES Outlet flowrate 2.67 cfs Pipe diameter 15 inches Outlet pipe slope 0.35 percent Full flow velocity 2.2 ft/sec Date 18-Jul-08 Designer JWP 1 1 1 Zone from graph above = Outlet pipe diameter 15 in. Outlet flowrate 2.7 cfs Outlet velocity 2.2 ft/sec Material = Class A Length = 5.0 ft. Width = 3.8 ft. Stone diameter = 3 in. Thickness = 9 in. Zone Material Diameter Thickness Length Width I Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class 1 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class 11 23 27 10 x D(o) 3 x D(o) 6 Class 11 23 27 10 x D(o) 3 x D(o) 7 1 Special study require Calculations based on NY DOT method - Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com cwl STEWART RIPRAP OUTLET PROTECTION WORKSHEET Project MCAS New River Hangar Date I8-Jul-08 Project No. C8020 Designer JWP Outlet ID 40-FES Outlet flowrate 1.13 cfs Pipe diameter 15 inches Outlet pipe slope 0.32 percent Full flow velocity 0.9 ft/sec .i 1 1 Zone from graph above = Outlet pipe diameter 15 in. Outlet flowrate 1.1 cfs Outlet velocity 0.9 ft/sec Material = Class A Length = 5.0 ft. Width = 3.8 ft. Stone diameter = 3 in. Thickness = 9 in. Zone Material Diameter Thickness Length Width I Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class 11 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study required Calculations based on NY DOT method - Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com l STEWART Project Project No. Outlet ID RIPRAP OUTLET PROTECTION WORKSHEET MCAS New River Hangar C8020 27-FES Outlet flowrate 5.08 cfs Pipe diameter 24 inches Outlet pipe slope 1.06 percent Full flow velocity 1.6 fVsec Date 18-Jul-08 Designer JWP ZIUMMA11111M 1 1 1 Zone from graph above = Outlet pipe diameter 24 in. Outlet flowrate 5.1 cfs Outlet velocity 1.6 ft/sec Material = Class A Length = 8.0 ft. Width = 6.0 ft. Stone diameter = 3 in. Thickness= 9in. Zone Material Diameter I Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class 1 13 22 8 x D(o) 3 x D(o) 4 Class 1 13 22 8 x D(o) 3 x D(o) 5 Class 11 23 27 10 x D(o) 3 x D(o) 6 Class 11 23 27 10 x D(o) 3 x D(o) 7 S ecial study required Calculations based on NY DOT method - Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com Buoyancy Check for Wetpond Riser C8020 Inside Dimensions Width 4.00 ft Length 4.00 ft Heigth 2.42 ft Wall Thickness 0.50 ft Bottom Thickness 0.50 ft Slab Len 5.00 ft Slab Wid 5.00 ft Slab Thic 1.00 ft Top Thick 0.50 ft Top Grate wid 3.00 ft Top Grate len 3.00 ft Wiser 60.50 cf Vbrick 21.78 cf Vconc 8.00 cf Vslab 25.00 cf Vtop 3.50 cf Fb 3,775.20 lb Factor of Safety 1.32 Fw must > 4,964.39 lb Fsubmerged solids 5,105.33 lb RISER IS : OK Start Node Stop Node Elevation Ground Start ft Elevation Ground Sto ft Invert (Upstream) ft Invert (Downstream) ft Length (ft) Diameter (n ) Material Slope (Calculated) % Flow (ft, /s) Velocity (Average) ft/s T-2 OF-11 11.00 5.00 7.00 3.00 298 12 Bare soil 1.34 2.89 2.68 0 SEESHEET W1WCW0OW5NUATION —_—_ r :M1Sa.n ////k attry-one' ec(j!1„. ro r� J 'lid 3 J NOTES sa sm arar mX smNr mew¢ I.az Au mmXu'nm suu eE n Nxwnwa mX KRIX ixowa. wmm mXnvE sPcaK.nor¢ wo m-n.®rs Amm� rw.is ue rtrNaXurxcT ewn imruma aaN:rm m na warm ccn:Ra xs=[cmX wu E mxwom m ce om¢a n .vnnG nawwc sum+¢ mx amulve m mr nva er IK wumt IK norunm eu a •rr¢.mr .arEKrrm. 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Town Point Center 150 Boush Street, Suite 1000 Norfolk, Virginia 23510 Prepared By: STEWART ENGINEERING, INC. 421 Fayetteville Street, Suite 400 Raleigh, North Carolina 27601 June 6, 2008 GEOTECHNICAL ENGINEERING REPORT PROPOSED AIRCRAFT MAINTENANCE HANGAR (P-526) MCAS New River Jacksonville, Onslow County, North Carolina Stewart Project No.: F8008.00 Prepared For: TRANSYSTEMS,INC. Town Point Center 150 Boush Street, Suite 1000 Norfolk, Virginia 23510 June 6, 2008 i STEWART a w eao,eRe 06/06/08 gyp. Donald V 'mown Jr., P.E. Senior Geotechnical Engineer r TABLE OF CONTENTS 1 EXECUTIVE SUMMARY................................................................................................ 1 2 PROJECT INFORMATION............................................................................................2 2.1 Site Location and Description............................................................................. 2 2.2 Project Understanding...................................................................................... 2 2.3 Scope of Services............................................................................................. 2 3 SUBSURFACE CONDITIONS........................................................................................ 4 3.1 Geology Overview............................................................................................ 4 3.2 Field Testing.................................................................................................... 4 3.3 Soil Classification & Laboratory Testing............................................................... 4 3.4 Soil Conditions................................................................................................ 5 3.5 Groundwater...................................................................................................6 4 ENGINEERING ASSESSMENT AND RECOMMENDATIONS ............................................. 7 4.1 General Discussion........................................................................................... 7 4.2 Site Preparation............................................................................................... 7 4.2.1 General...............................................................................................7 4.2.2 Parking Lot........................................................................................... 7 4.2.3 Hangar................................................................................................8 4.3 Structural Fill.................................................................................................. 8 4.4 Seismic.......................................................................................................... 9 4.5 Foundations...................................................................................................10 4.5.1 Driven PCPS Concrete Piles....................................................................11 4.5.2 Micropiles...........................................................................................12 4.6 Slabs-On-Grade..............................................................................................13 5 CLOSING..................................................................................................................14 Appendix o Site Location Map (Figure No. 1) o Test Location Diagram (Figure No. 2) o Boring/CPT Logs o General Soil Profile (Figure Nos. 3 & 4) o Laboratory Test Results o Liquefaction Analyses o Lateral Pile Capacity p-y Curves o Legend To Soil Descriptions (Figure No. 5) 1IJ Stewart Engineering, Inc. (Stewart) has completed a geotechnical exploration at the site of the proposed Aircraft Maintenance Hangar (P-526) at MCAS New River in Jacksonville, North Carolina. A summary of our findings, opinions and recommendations are provided below. Condition Comment Total Number of SPT Borings/CPTs 8/7 Test Depth (ft) 10 to 70 Soil Types Encountered (USCS) CH, CL, ML, OL, SM, SC, SP, SW Groundwater (ft) 5 to 10 Seismic Site Characterization F Recommended Foundation Systems 1. Driven Concrete Piles 2. Micro -piles 1. Relatively soft/loose subgrade soil, coupled with the heavy structural loading (compression, uplift and lateral), will require deep foundations as noted above. Other Items of Note 2. Liquefaction is expected during a seismic event, which would result in ground subsidence (settlements) and foundation strength loss. 3. Soft, plastic clays in the parking lot will require special treatment and staging. The owner/designer/contractor should not rely solely upon the summary table above. This report should be read in its entirety prior to implementing the recommendations in the preparation of design and construction documents. Stewart Engineering should be retained to perform sufficient services to determine plan/specification compliance with the recommendations in this report. Page 2 2 PROJECT INFORMATION 2.1 Site Location and Description The subject site is located southeast of Foster Street, south of its intersection with Campbell Street in Jacksonville, North Carolina. More specifically the site is located east of an existing aircraft hangar on the MCAS New River complex. See Figure No. 1 in the Appendix of this report for the general site area. The main site area is currently developed as a concrete -paved aircraft parking area. The area is generally Flat with about 2 feet of fall (downward elevation change) from west to east within the proposed building footprint. The ground surface just north of the concrete pad sloped downward to the north approximately 3 to 6 feet, into a large undeveloped grass field. A drainage feature is located in the southern portion of the field. In addition, numerous buried utilities including water, communications, steam and electric were marked by others during our time onsite. 2.2 Project Understanding We understand that the proposed hangar (P-526) will be a one- to two-story, 72,800 square foot (560 feet by 130 feet in plan view) building with steel framing and non -load bearing masonry walls. The prototypical foundation is a pre -cast, pre -stressed concrete pile system. Maximum compression loads are anticipated to range from 400 to 1,500 kips. The ground Floor is intended to be a grade -supported concrete slab, which will either require new fill placement or will be stepped down to accommodate for the existing elevation change within the building footprint. The slab will be subjected to a maximum of 2.5 kips from concentrated aircraft wheel loads. ® The area north of the proposed hanger will be developed into a new vehicle parking area. The parking lot will be about 552.feet long and 185 feet wide. It will be asphalt -paved. Immediately north of the parking lot, a storm water detention system will be construction. The type of system is not certain at this time. We anticipate less than 1 foot of cut or fill will be required to establish finished subgrade elevations in the proposed building area; however, the parking lot may require up to 6 feet of fill to raise it to the same grade as the proposed building pad. The information presented in this section was utilized in the geotechnical analysis. Therefore, if any of the noted information is incorrect or has changed, please inform us so that we may amend the recommendations presented in this report, if appropriate or necessary. 2.3 Scope of Services The purpose of this geotechnical exploration was to gather pertinent subsurface information at this site in order to provide opinions and recommendations regarding the design of foundation system as well as geotechnical and construction guidelines with regards to the understanding of the proposed site development. For this project, the following scope of services was performed: • Coordinated the location of the existing underground utilities in the general area; • Visited the site to observe/document the general surface conditions and mark test locations; • Advanced a total of eight soil test borings with standard penetration testing and seven cone penetration tests; • Prepared a Boring Log or CPT Log for each test location that stratifies the types of soil encountered, presents the results of the Standard Penetration Testing (SPT) or cone resistances, as well as other relevant geotechnical information; Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 3 • Prepared a Site Location Map to show the site vicinity and a Test Location Diagram to illustrate the approximate test locations; • Conducted a geotechnical engineering assessment of the data collected in the field and prepared this report to provide recommendations for: o foundation support system(s) including recommend capacities and estimated settlements (total and differential); o slab -on -grade design considerations, including subgrade reaction modulus; o seismic site classification; o liquefaction assessment; and o construction considerations, such as fill soil suitability, grading, subgrade preparation, compaction, foundation installation, excavation, groundwater management and quality control. Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 4 3.1 Geology Overview The subject site is located within Onslow County, North Carolina, which lies within the Coastal Plain Physiographic Province of the eastern United States. This province is characterized by gently sloping plains with numerous broad, slowly moving rivers with broad flood plains. Low-lying marsh and swamp regions are also prevalent. The Coastal Plain is comprised of sediments (mainly sands and clays) that have been transported eastward from highlands to the west by erosional forces. Some of these sediments have been consolidated to form sedimentary rock beds such as sandstone and mudstone; however, often the sediments are poorly consolidated or unconsolidated. This process began approximately 200 million years ago and, based on seismic refraction and well data, the depth of these sediments to the underlying basement rock ranges from less than 10 feet at the fall line (the western boundary of the Coastal Plain and the eastern boundary of the Piedmont) to approximately 10,000 feet at Cape Hatteras. Deposition commonly occurred beneath the sea and numerous lenses and beds of hard limestone also occur within the Coastal Plain strata. Review of the Geologic Map of North Carolina (compiled by the North Carolina Geological Survey, 1985) indicates that the subject site is underlain by the River Bend Formation (Tor), comprised of "limestone calcarenite overlain by intercalated with indurated sandy molluscan -mold limestone". 3.2 Field Testing Upon arrival, the concrete slab was cored using a thin -walled concrete core barrel at six test locations to allow access to the subgrade. Subsequently, the subsurface conditions at the site were evaluated with a total of eight soil test borings (B-1, B-3, B-4 B-6, PL-1, PL-3, PL-4 and SD-1). The borings extended to depths of approximately 10 to 70 feet below the current ground surface. The test locations were marked in the field by Stewart Engineering's survey personnel. A Test Location Diagram (Figure No. 2), which indicates the approximate test locations, is presented in the Appendix of this report. Soil test borings were advanced at this site utilizing a trailer -mounted CME 45 drilling rig using mud -rotary drilling methods. All boring and sampling operations were conducted in general compliance with ASTM D1586. At predetermined intervals, soil samples were obtained with a split -barrel sampler (standard 2- inch O.D.). The sampler was rested on the bottom of the borehole and driven to a penetration of 18 inches (or fraction thereof) with blows of a manual 140-pound drop hammer falling 30 inches. Of the 18 inches, the number of hammer blows required to achieve 6 inches of penetration is recorded for three consecutive segments. The sum of the blow counts for the second and third 6-inch segment is termed the Standard Penetration Test (SPT) resistance, or N-value. Testing also involved performing seven Cone Penetration Tests (CPT) at B-2, B-5, B-7, B-8, B-9, PL-2 and PL-5. The Cone Penetration Tests were conducted with a track -mounted CPT unit. CPT is a continuous testing process, by which the cone penetrometer device is advanced into the ground with a slender rod that is mobilized by a hydraulic press. The penetrometer is comprised of a 60-degree cone tip, a cylindrical sleeve and internal load transducers. As the penetrometer is pushed into the ground, resistance readings at the tip and along the sides of the sleeve are transmitted back to the rig via cabling and continuously recorded by a laptop computer. The penetrometer utilized on this site was also equipped to record relative pore water pressure and shear wave velocity. Infiltration testing for the proposed storm water detention pond, which is included in our scope, was not conducted as part of the initial site testing. The infiltration testing will be completed at a later date and the results will be forwarded in a report addendum. 3.3 Soil Classification & Laboratory Testing The soil samples obtained during the drilling operation were classified and logged in the field by a Professional Engineer in general accordance with ASTM D2488. The samples were then placed in sealed containers and transported to our laboratory for further analyses and testing. The Boring Logs, CPT Logs Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 5 and the "Legend To Soil Descriptions", which explain the terms and symbols used on the logs, are included in the Appendix of this report. Unless otherwise requested, all samples will be disposed of after 2 months. Select soil samples were also subjected to laboratory testing, which included moisture/water content and gradation. The proposed Atterberg Limits tests were foregone due to the main soil type being sand and instead additional sieve analyses were conducted. The results of the testing are provided in the Appendix of this report, as well as on the respective boring log. 3.4 Soil Conditions Details of subsurface conditions encountered during the field exploration program are shown on the individual logs included in the Appendix of this report. The existing site topography shown on the plan provided to us was utilized to estimate the ground surface elevations. As such, the ground surface elevations presented on the Boring Logs or referenced in this report should be considered approximate. Please note that no ground surface elevations were available for the grass field to receive the new parking lot, therefore none are referenced in that area. The following subsurface description is of a generalized nature, provided to highlight the major soil strata encountered. The stratification of the subgrade materials illustrated on the boring logs represents the conditions in the actual test locations; therefore, variations should be expected between borings. Stratigraphy boundaries only represent the approximate depth/elevation of a noticed material change, and the transition between material types is typically gradual. Furthermore, it is often difficult to discern between clean fill soil and native material. A brief summary of the soils encountered is below GROUND COVER - Initially, tests B-4 through B-9 encountered approximately 6 to 10 inches of concrete. Tests B-2, B-3, PL-1 through PL-5 and SD-1 encountered approximately 6 to 8 inches of topsoil at the ground surface. Test B-1 encountered a 2-inch layer of asphalt at the surface, with no stone base course. ® FILL SOILS - Fill soils were encountered in the concrete pad area (tests B-1 through B-9) to approximately 4 to 6 feet below grade. The fill soils generally consist of SANDS (SW, SM and SC) with some lesser clay layers. NATIVE SOILS - The native soils, which are Coastal Plain sedimentary deposits, generally consisted of a layer of soft CLAYS (CH and CL), soft SILTS (ML and OL) underlain by very loose to very dense SANDS (SP-SM and SM) were encountered below the fill or ground cover. Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 6 3.5 Groundwater Groundwater level measurements were recorded at the time of completion of testing at each of the borings performed at the site. The soil test borings within the proposed building footprint were left open for about 15 hours for a stabilized groundwater reading. The depths to groundwater are presented in the following table. Table 1: Groundwater Depths O-Hr Reading 15-Hour Reading B-1 10 10 B-3 8 9 B-4 8 9 B-6 9.5 10 PL-1 6 Not Measured PL-3 5 Not Measured PL-4 5 Not Measured SD-6 5 Not Measured ® The reported groundwater conditions represent the conditions at the time of the exploration. Fluctuations in groundwater levels are common and should be expected. Common factors that influence groundwater levels include, but are not limited to, soil stratification, climate/weather, nearby bodies of water (lakes, ponds, etc.), underground springs, streams, rivers and surface water discharge. At the onset, as well as continually throughout the construction process, the contractor should monitor groundwater levels if determined to be detrimental to the project. Management of groundwater can significantly impact construction procedures/practices, schedules and project budgets. Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 7 4 4.1 General Discussion In general, the site appears to be readily adaptable for the proposed construction; however, due to the loose/soft subgrade soil conditions and the heavy loading, the proposed structure will require a deep foundation system. Also due to the loose sands, there is a high potential for liquefaction in the event of a seismic event. This condition will be needed to be addressed in the design of the structure. 4.2 Site Preparation 4.2.1 General Initially, all concrete, asphalt, utilities and trench backfll, vegetation, debris and any other deleterious materials should be cleared from the proposed areas scheduled for site development. The existing grass field, which will be developed into the vehicle parking lot, should be thoroughly stripped with all topsoil and root mat removed. This also applies to the grass strip along the northern edge of the existing concrete pad and the existing slope. Based on the borings, we recommend a stripping depth of 1 foot, but deeper isolated pockets may be encountered that will require removal. Stripping should extend a lateral distance of at least 2 feet beyond the limits of the new construction. Prior to fill placement in low areas (including undercut areas) and prior to stone base placement in areas at grade, the near -surface soils should be evaluated by the Geotechnical Engineer. This is typically accomplished by proofrolling, but the soft condition at the site will likely require other means of evaluation. This may include probing with a 1/2-inch diameter T-rod or testing with a dual -mass (Kessler) dynamic cone penetrometer (DCP). In areas where proofrolling is determined to be viable, particularly at the finished subgrade elevation, this should be accomplished with a loaded tandem -axle dump truck with repeated passes over the subject area. Areas that yield (rut, pump or deflect excessively) during proofrolling, or are otherwise deemed unsatisfactory for fill placement or pavement support, should be repaired as recommended by the Geotechnical Engineer. Typically, repair will require undercutting and replacement. Where applicable, geogrid may be used to lessen the depth of undercutting required. 4.2.2 Parking Lot Boring PL-1 encountered organic silt (OL), which is unsuitable for pavement support, to a depth of approximately 5 feet below the existing grade. To prevent long term pavement issues in this area, the organic silt should be completely removed and replaced. However, the cost and time associated with doing so is expected to be unfavorable. Depending on the depth of fill to be placed in this area, some or all of the OL-material can be left in place if the owner acknowledges the risk associated with doing so. These risks, which wouldn't likely be evident for several years, include compromised pavement performance including subsidence (birdbaths), potholes and pavement cracking. Utilities traversing this area may also be affected by the gradual compression/deterioration of the OL-material. Aside from the above mentioned organic silt layer, the proposed parking lot area is generally underlain by highly plastic clays and clayey sands. The plastic clays are poor pavement support materials that could possibly undergo volume change (shrink -swell) with changes in water content and will lose considerable strength when wetted. These soils are expected to cause premature pavement failure (cracking, potholes, etc.) if left in place to provide direct support the pavement structure. As such, we recommend that these soils be undercut and replaced or bridged with granular structural fill. Based on the soft consistency of the clays, we expect that a minimum of 3 feet of undercut or bridging will be necessary. We also expect that a layer of geogrid will be required to establish a stable base on which to begin filling, regardless of whether the subgrade is undercut or not. We recommend using a biaxial geogrid such as Tensar BX-1200 or equivalent. Depending on the subgrade conditions at the time of construction, a layer of crushed aggregate may be necessary directly on top of the geogrid. In the absence of proposed grading plans at the time of this report, we have assumed that 3 to 6 feet of fill will be placed to raise the proposed parking lot grades. In doing so, the weight of the new fill will cause the underlying clays to consolidate, causing settlement at the ground surface. Also, if loose bridging is required, this material will also undergo some settlement. No specific laboratory testing was conducted to Proposed Aircraft Maintenance Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 8 assess the magnitude of consolidation or time rate of settlement for the clays; however, we estimate these to be on the order of 4-8 inches over four to six months (without surcharging). As such, we recommend placing the fill in the proposed parking lot area early in the construction phase to allow the consolidation process to be reach completion before final grading and paving operation begin. Where new fill will be placed against the existing slope, located along the north side of the proposed hangar, the existing slope should be benched to allow for proper placement and compaction of the new fill. Benches should not exceed 3 feet in height and the bench width should be 2 to 3 times the bench height. 4.2.3 Hangar The near surface soils across the proposed building pad consist of sands with varying amounts of silt and/or clay. Once the existing concrete slab is removed, the surface soils should be compacted in -place to achieve 100 percent compaction, based on a Modified Proctor Test (ASTM D1557). Scarification and moisture conditioning may be required. Similar to the parking lot area discussed above, addition of fill on the building pad will result in consolidation of the existing subgrade soil. Based on a fill thickness of 2 feet, we estimate as much as 2 inches of settlement, which will likely require two months (without surcharging). Surcharging could reduce this delay by one-third to one-half. During the settlement period, work would have to be shifted to other areas of the site since the settlement would damage overlying construction. This settlement would also result additional down -drag on a pile foundation so pile installation would also need to be delayed. Given the impact of new fill in the building pad, we recommend that Whiting-Tumer's proposal to step-down the slab be given serious consideration as this would significantly reduce or eliminate settlements stemming from new fill. 4.3 Structural Fill Structural fill should possess a maximum dry density (MDD) of 100 pounds per cubic foot (pcf) or greater as determined by the Modified Proctor Compaction Test (ASTM D1557). Any material utilized as structural fill should not contain rocks greater than 3 inches in diameter or greater than 25% retained on the 3/4-inch sieve. Structural fill material should not contain more than 6% (by weight) of organic matter or other deleterious material. It is preferable for the Plasticity Index (PI) of structural fill soil to not exceed 20 and the Liquid Limit (LL) not exceed 40, as determined by Atterberg Limit testing (ASTM D4318). This corresponds to Unified Soil Classification System (USCS) designations of GIN, GM, GC, SW, SM, ML and some SC and CL. Structural fill required to establish subgrade elevations should be placed in 8-inch thick (or less) loose lifts. Fill soils should be compacted to the minimum percentages in Table 2, which is based on a Modified Proctor Compaction Test (ASTM D1557). The moisture content of fill soils should be maintained within f2% of the material's optimum moisture content as determined by the same standard. Some moisture conditioning of fill material may be necessary prior to placement, of which drying during the wet season always proves to be the most challenging, particularly with clay -rich soil. Aggregate Base Course stone below pavements and slabs should be compacted to 100% of the material's maximum dry density as determined by a Modified Proctor Test, within t2% of the stone's optimum moisture content. Table 2: Compaction Reauirements Fill Soil Locati Compaction Building Pad 95 Parking Lot 95 Airfield Pavement 100 - Upper 24 inches 95 - Below 24 inches Non -Structural Areas 90 ;Percent of the material's maximum dry density per ASTM D155Z Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 9 It is recommended that the placement and compaction of structural fill be monitored by an Engineering Technician, working under the direction of the Geotechnical Engineer. We also offer the following recommendations for compaction testing frequency: • Building Pad - 1 test per lift per 1,500 square feet of fill placed • Parking Lot - 1 test per lift per 4,000 square feet of fill placed • Trench backfill - 1 test per lift per 100 linear feet of trench backfill 4.4 Seismic Per the International Building Code, 2006 Edition (IBC2006), the design of structures must consider dynamic forces resulting from seismic events, regardless of their likelihood of occurrence. These forces are dependent upon the magnitude of the earthquake event as well as the properties of the soils that underlie the site. As part of a generalized procedure to estimate seismic forces, the code assigns a Seismic Site Classification (letter designation of Class A through F). The classification is based on the subgrade soil/rock conditions within the upper 100 feet of the ground surface at the subject site. To define the Seismic Site Class for this project, we have interpreted the results of soil test borings and the shear wave velocity data collected within the project site. Below the termination depths, the soil properties were conservatively estimated to a depth of 100 feet. The average shear wave velocity and average SPT N-values are consistent with a Seismic Site Class "D"; however, as defined in Table 1613.5.2 of theIBC2006, the presence of liquefiable sands automatically downgrade the site to a Seismic Site Classification "F". As such, Seismic Site Class "F" should be used in the design of the proposed structures. The associated USGS-NEHRP (2002) probabilistic ground acceleration values and site coefficients for the general site area were obtained via the U.S. Geologic Survey (USGS) Ground Motion Parameter Calculator at the geohazards webpage (http://earthguake.usgs.ciov/research/hazmar)s/design) and are presented in the following table. These values are based on a Seismic Site Classification "D", as permitted by "Note b" in the IBC2006 Tables 1613.5.3 (1 & 2) that defers to ASCE 7 as stating: "...for structures with periods of vibration equal to or less then 0.5 seconds, values of F for liquefiable soils are permitted to be taken equal to the values for the site class determined without regard to liquefaction ...." In the event that the structure is determined to have a period greater than 0.5 seconds, a site -specific seismic response analysis will be required. Table 3: Ground Motion Values* Adjusted Design Spectral Spectral Acceleration Acceleration mmm (g) i i . (g) 0.2 Ss 0.204 Fa 1.6 ,0.326 Sos .21217 1.0 St 0.076 F„ 2.4 SrnISni0.183 0.2 SDI '2 % Probability of Event in 50 years for Latitude 34.717289 and Longitude-77.440938. "MCE random horizontal component of acceleration at 8-C interface (i.e. top of bedrock). MCE = Maximum Considered Earthquake For Seismic Design Category designations of C, D, E or F, which are contingent on the structure's "Seismic Use Group", the code requires an assessment of slope stability, liquefaction potential and surface rupture due to faulting or lateral spreading. Detailed evaluations of these factors were beyond the scope of this study. However, the following table presents a qualitative assessment of these issues considering the site class, the subsurface soil properties, the groundwater elevation and probabilistic ground motions. Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 10 Table 4: Qualitative Seismic Site Assessments Hazard I Comments In the event of an earthquake with a USGS recommended design Mean Moment Magnitude (Mw) Liquefaction High 6.76, some of the sands below the water table are likely to liquefy. Please refer to Table 5. Slope Stability* Low Based on the presumed grading, significant cut and fill slopes are not planned for construction. No known active faults underlie the site and no lateral Surface Rupture Low spreading or boils are anticipated during a seismic event. *A slope stability analysis, including it's stability during a seismic event, was beyond the scope of work. Based on our assessment using Liquefy 5 computer software, the potential for liquefaction is isolated to a loose sand zone generally encountered from about 29 to 36 feet below the existing grade (approximate elevation -10 to -17 feet MSL). According to the CPT soundings, this weak zone is fairly consistent across the site. The table below presents the liquefiable zones established in our analysis as well as the estimated post -liquefaction settlement/subsidence at the ground surface. Table 5: Liquefaction Zones Test Location Liquefiable Zone (feet) Liquefaction -Induced Settlement (inches) Liquefaction -induced foundation settlement will jeopardize the proposed deep foundations and concrete slab -on -grade; therefore, the Owner and Structural Engineer must choose whether mitigation of liquefaction -induced settlement is absolutely necessary for the facility to perform as intended. Furthermore, it should be noted that liquefaction mitigation measures are intended to reduce the likelihood of catastrophic failure and should not be misconstrued as a preventative measure against settlement and/or other structural damage since such conditions cannot be completely avoided during an earthquake. Mitigation measures typically involve a ground modification via an extensive array of earthquake drains or vibro-replacement (stone columns), penetrating into the liquefiable layer, to relieve excess pore water pressure that builds up and cause liquefaction during an earthquake. Another approach would be to designing for full effects of liquefaction (e.g. fully reinforced floor slabs spanning between pile -supported grade beams, using reduced pile capacities, etc.). Additional engineering analyses will be necessary to provide recommendations for liquefaction mitigation systems. 4.5 Foundations The provided project narrative indicates that the prototypical foundation system uses driven 12-inch pre- cast, pre -stressed (PCPS) concrete piles. While we agree that piles are a viable foundation system, they are limited in capacity during an earthquake due to strength losses associated with liquefaction and their relatively shallow bearing depth. As such, we are also providing recommendations for 14-inch PCPS concrete piles and micro -piles as alternatives to consider. Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 11 4.5.1 Driven PCPS Concrete Piles Based on the subgrade conditions and the heavy structural loads, driven pre -cast, pre -stressed concrete piles are considered a suitable foundation system. We recommend using a 12-inch or 14-inch square pile. Driven displacement piles such as these will derive their strength from both end bearing conditions and the shaft (skin) resistance along the pile sides. Based on our testing we estimate that piles can be driven to an approximate tip depth of 55 feet (f5 feet); however, pile drivability should be verified by the pile installer by using the equation method taking into account the proposed pile driving equipment (IBC2006, Section 1808.2.8.2). At a tip depth of 55 feet, we recommend the following capacities to limit post - construction settlements: Table 6: Pile 12-inch PCPS 80 [30] 40 (30] 6 9 13 Concrete 14-inch PCPS Concrete 1 100 [40] 60 [50] 8 12 18 Note: The capacity values in this table are per pile. The capacity values in brackets account for the reduced capacity and down -drag forces expected dunng liquefaction. 'Free -head condition. As discussed in the previous section, liquefaction of the loose sands below the site will significantly impact the proposed foundation. During liquefaction, the piles will loose bearing capacity due to loss of side ® friction. In fact, the liquefaction will create negative skin friction (down -drag) as the soil settle around the pile causing additional loading on the pile. As such, we are recommending the bracketed ([]) pile capacities in Table 6 if liquefaction is not mitigated. If liquefaction is mitigated, the higher pile capacity may be used. Piles should be constructed according to IBC2006 with concrete having a minimum compressive strength of 5,000 psi and a 700 psi pre -stress load. Piles should be spaced a minimum of three times the pile width (3xD). Selection, construction and installation of the piles should also be in accordance with the IBC2006 1809.2.3. Proper pile handling and driving are critical to pile strength and longevity. Piles should be transported and handled in a manner that will not cause damage to the concrete or reinforcing steel. All piles should be inspected prior to driving to verify their condition. Also, pile driving equipment should be appropriately sized to drive the piles to the planned depths, but should not overstress the pile. We recommend that the pile driving contractor submit pile driving plans to the Geotechnical Engineer for review prior to mobilization of pile driving equipment. This should, at minimum, include the hammer and cushion specifications, pile drivability verification (WEAP analysis) and quality control plan. It is imperative that the pile driving contractor verify that the piles can be driven to the design depth without causing damage to the pile so that any necessary design changes can be made before mobilization. We recommend the following pile load testing program options: Dynamic Testing - We recommend driving 12 test piles, evenly spaced across the site, prior to construction. These piles should be instrumented and analyzed with a Pile Driving Analyzer (PDA) according to ASTM D4945. These piles should be used as a benchmark for verifying the design and for ordering the production piles. Static Testing - In the absence of dynamic load testing, we recommend performing a minimum of three static load tests prior to construction. Two should be a compression load test in accordance with ASTM D1143 while the other should be a tension load test in accordance with ASTM D3689. Since battered piles are expected to be required to resist O Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 12 ® the large lateral loads, we do not see the need for lateral load testing. Static load tests should be performed to 21/2 times the design load. Since the sands below the site may exhibit "quick" conditions (i.e. significant instantaneous strength loss due to excessive pore water pressure build-up), some piles may not achieve the prescribed resistance at the anticipated depths during initial driving. As such, capacities at re -strike should also be considered. A representative of the Geotechnical Engineer should be contracted to observe and document the installation of the test and production piles as well as the load testing procedures. 4.5.2 Microoiles As an alternative to driven piles, we recommend considering a micro -pile (a.k.a. pin pile and mini -pile) foundation system. Micro -piles are relatively small diameter, bored and cast -in -place piles. The piles are constructed using neat grout and reinforcing steel (pipe and/or bar). While some end bearing is attained by each micro -pile, it is ignored and designed solely on the side friction resistance which is achieved through the grout -to -soil bond. One distinct advantage to micro -piles is that their penetration depths are not limited by dense soil layers, unlike driven piles. This allows the micro -piles to be installed to greater depths and in this case develop additional capacity needed in the event of liquefaction. One disadvantage to such a system is the reduced lateral capacity requiring additional battered piles when compared to PCPS piles. Based on typical bond strengths provided in the Federal Highway Administration's Micropile Design and Construction Guidelines manual (FHWA-SA-91-070), we have estimated the capacities in Table 7 for an 8- inch diameter micropile. Please note these values are for preliminary design only and the design -build foundation contractor should verify actual pile capacities and material strengths. In fact, we recommend conducting a test program consisting of at least two static load tests at the site to determine/verify bond strengths to maximize the pile design. Table 7: Microoile Capacities •-LILaptaecral Compres) ion] Qons)�] 85 130 [60] 130 (120) 1.5 EE 100 160 [90] 160[150] Note: The capacity values in this table are per pile based on a grout compressive strength of 5,000 psi and 75 ksl steel. The capacity values in brackets account for the reduced capacity and down - drag forces expected dunng liquefaction. Design, construction and installation of the micropiles should also be in accordance with the IBC2006 1810.8. We recommend a minimum grout compression strength of 5,000 psi and 75 ksi (minimum) reinforcing steel. As with the PCPS Concrete piles, load testing will be required per IBC2006 section 1808.2.8.2 to utilize the capacities/stresses in Table 7. Micropiles should be spaced a minimum of three times the pile diameter (3xD). A representative of the Geotechnical Engineer should be contracted to observe and document the installation of the test and production piles as well as the load testing. O Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008. 00 Page 13 4.6 Slabs -On -Grade For grade -supported concrete slabs constructed over a properly prepared subgrade, we recommend a modulus of subgrade reaction (k) of 110 pounds per cubic inch (pci). This value is estimated based on correlations to a plate load test (30-inch diameter) without consideration of liquefaction. We recommend that floor slabs be underlain by a minimum of 8 inches of compacted aggregate base course material. The aggregate base course material should be compacted in accordance with Section 4.3 of this report. Open -graded crushed stone, such as No. 57-sized aggregate, may also be used; however, it is our experience that open graded crushed stone can collect water during periods of rain and cause saturation and softening of the subgrade soils prior to placement of the floor slab. Therefore, construction sequencing/timing and the season in which the stone is placed should be taken into consideration. It is important to point out that cracking of concrete is normal and should be expected. Proper jointing of slabs is paramount in the control of cracking. The American Concrete Institute (ACI) recommends a maximum panel size (in feet) equal to approximately three times the thickness of the slab (in inches) in both directions. Controlling the water -cement ratio of the concrete, particularly after batching, and including fiber reinforcement in the mix can also help reduce shrinkage cracking. Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008.00 Page 14 PEORTOTUM The opinions and recommendations herein are based on the subsurface information collected during our exploration and the provided design details for the proposed project. Change to the proposed development plans should be made known to Stewart Engineering so that any necessary adjustments to our recommendations can be made prior to final design. If not, Stewart Engineering cannot be held responsible for any resulting discrepancies. This report has been prepared for the exclusive use of TranSystems, Inc. for the specific application to the proposed Aircraft Maintenance Hangar (P-526) at the MCAS New River Facility in Jacksonville, North Carolina. The engineering recommendations contained within this report are in general accordance with the accepted professional geotechnical engineering practices and the industry's standard of care in this region. No warranties or guarantees are expressed and should not otherwise be implied. Stewart Engineering would be pleased to review the final project documents to check compliance with the recommendation within this report. Also, we can provide materials testing and special inspection should the need arise on this project. When you feel the time is appropriate to discuss these additional services, please do not hesitate to call us. Proposed Aircraft Maintenence Hangar (P-526) Jacksonville, North Carolina Stewart Project No. F8008.00 Figure No. 1: Site Location Diagram SD -I 2 TW) ="te PL-2 j3 j3 Nei j; -2 .4 20' CLEM —�XFV— MCE Yfa S-9 B-4 -5 PROPOSED AIRCRAFT -IkIAINTEM C. HA P_52 :/GAR P_651 B �I Z;7 BORING LOCATION DIAGRAM :a7 wIr F8(008�2`O0O NTS STEWART ENGINEERING, INC.BRAWNG MMDM BY. DAM 421 FAYE7rEVILLE STREET, SUITE 400 New Aircraft Maintenance Hangar others 05-28-083p �er �mm RALEIGH, NORTH CAROLINA 27601 MCAS New River FIBT, Jacksonville, NC DWB 2 C� Ste Engineering, Inc. BORING NUMBER B-1 Fayetteville Street, Suite 400 CStewart PAGE 1 OF 1 Raleigh, North Carolina 27601 Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSystems Inc. PROJECT NAME MCAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5/15108 COMPLETED 5/16108 GROUND ELEVATION 19 ft BORING DEPTH 701t DRILLING CONTRACTOR Mid -Atlantic Drilling 0-HR GWL 10 ft STAB. GWL 10 ft CAVE41N 25 ft DRILLING METHOD Mud Rotary AUGER SIZE 2.25-inch NOTES DRILL RIG CME 45 (Trailer) HAMMER TYPE Manual LOGGED BY DWB ♦ SPT N-VALUE (BPF) m a o a 1020 w 40 W6070 ao 90 PL MC LL O c M w j n 10 zor3o ao 5�0 so 7orao 90 jF N a� L¢i 3Z ❑ FINES CONTENT (%) ❑ w p j MATERIAL DESCRIPTION < m N m 0 Z 10 20 30 40 50 60 70 80 90 18.8 0.2 Sp ASPHALT PAVEMENT (2 INCHES, NO GRAVEL BASE) SS 1 5 5 4 9 SM POSSIBLE FILL - TAN COARSE SAND - MOIST 15.0 4.0 SS 1 2 2 4 ..:...;..:......:.. ...:. POSSIBLE FILL - BROWN, SILTY FINE SAND WITH THIN CLAY SEAMS - MOIST 2 CH 3 2 3 2 5 SOFT TO FIRM, BROWN TO DARK GRAY, FINE SANDY SILT - 10.5 8.& MOIST SS 4 1 2 1 2 3 VERY LOOSE TO MEDIUM DENSE GRAY SAND WITH SOME SILT AND CLAY - WET TO SATURATED • SS 5 7 8 9 17 ... .... i...i......:... SP '. SM : SS 7 o: -8.51 27.5 " ...:..:..:.......y...: ..:...:...:.. ' MEDIUM DENSE TO VERY DENSE, LIGHT GRAY TO TAN, COARSE :'. SAND AND FRACTURED LIMESTONE WITH SHELLS AND SOME g 1 0 1 1 ..:.. _..:...:...:.. _..:.......... . CLAY/SILT - SATURATED ''. SS 1 1 2 3 °i...:..:...... ...�.....:...:. 9 SS 9 15 13 28 :.. SS 11 7 8 10 18 ...i..:..:... i...i...:..;. SM .:. SS 11 11 10 21 ., .: SS 13 23 27 38 65 ...... _..:...:..... _..:...:...:. SS 14 10 11 9 20 .: SS 15 9 12 16 28 ...; ..:..:...:...:..:...;...:. -48.01 67. : +. ...:.. _.....:...:.. _..:...:...:.. ...>..;...;......;. DENSE, OLIVE -TAN SILTY FINE SAND WITH TRACE SHELLS AND -51.0 70.0 SM TRACE LIMESTONE FRAGMENTS - SATURATED 16 12 20 27 47 Bottom of borehole at 70.0 feet. r/we: srrewca,c, arere-e+rn�6 dper�ennwsmnvtays ouv,�oreo. MAD. �e Operator Donald B Coogan Cone Number DSGO867 Date And Time 511412008 1:02:00 PM J { 'LA J' Job Number F8008.00 Location New River Air Station Hole Number B-2 CO Water Table Depth 0.00 tt GPS 3443.0617N, 07726.4703W Stewart Engineering o W REMARKS I>_ Wp Tip Resistance Pore Pressure Friction Ratio SPT N' O w a 0 Ot TSF 600 .20 Pw PSI 60 0 Fs/Ct M 4 0 60% Hammer 90 0 U) m 0 10 20 i I I _ . I ! . I I i I i ........... 'ill Ilil ... I ..I ... .. I i i l ! I I I I .... L I . i! I II !II '.i iil _ _I , ... i_... .I I.. I I I II fl II II 30 I L..._ L... 1..... L......a I I ... _....._ ........_L. .. ... .. _L. ........ ....._ ...._I. .. .......... I I 40 I I I I I I I I I I I III I i l 50 I l i I l l III L I I-_! i I I l i I 11 I I ! I i t ; I I I I f III i II II III iII I I11'll �. I I I l ❑ 1 - sensitive fine grained ■ 4 - silty clay to clay 07. silty sand to sandy silt ■ 10 - gravelly sand to sand 02. organic material ■ 5 - clayey silt to silty clay O 8 - sand to silty sand ■ 11 - verystiff fine grained(*) ■ 3 - clay ■ 6 - sandy silt to clayey silt D 9 - sand IN 12 - sand to clayey sand (•) Engineering, Inc. BORING NUMBER B-3 421 Fayetteville Street, Suite 400 CStewart Raleigh, North Carolina 27601 PAGE 1 OF 1 Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSystems, Inc. PROJECT NAME MICAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5/14/08 COMPLETED 5/14/08 GROUND ELEVATION 19 ft BORING DEPTH 50 ft DRILLING CONTRACTOR Mid -Atlantic Drilling 04HR GWL 8 it STAB. GWL 9 it CAVE-IN 19 it DRILLING METHOD Mud Rotary AUGER SIZE 2.25-inch NOTES DRILL RIG CME 45 (Trailer) HAMMER TYPE Manual LOGGEDBY DWB ♦ SPT N-VALUE (BPF) m Q. 10 20 30 40 50 60 70 60 90 PL MC LL Z c > w w > a n u1 10 zo 30 40 so 0 70 e0 so ❑FINES CONTENT (%) ❑ w o j MATERIAL DESCRIPTION Q Z 3 N m 0 Z 10 20 30 40 50 su 70 W so TOPSOIL (8 inches) SS 9 7 9 8 17 FILL - BROWN AND GRAY, CLAYEY SAND WITH SANDY CLAY (CL) 1 """""""""""""""' SC LAYERS - MOIST SS ...: 5 6 6 12 ......�..............:..:.. 13.0 6.0 2 FIRM, GRAY SANDY CLAY - MOIST 3S 3 2 3 5 CL 10.3 8. LOOSE, GRAY, CLAYEY SAND -MOIST TO WET 4 2 4 1 5 SC FIRM, GRAY AND TAN SILTY CLAY - WET TO SATURATED CH 4.7 142 SS 0 0 9 9 .. i..............i..;.. LIGHT GRAY SAND WITH SOME SILT AND CLAY - SATURATED 5 is .. ...:....:...:...:.. _..:...:. SS A 6 11 12 12 24. SP ". s 5 6 10 16 °.:.. ..:...:...:.. _..:...:. SM COLOR TRANSITIONS TO BLUE -GRAY -26 FEET SS ...'...:..:.......... . e 6 52 7 SS 3 1 2 3 ................. .:...:...:... 9 7.0 36.0 DENSE TO MEDIUM DENSE, LIGHT GRAY CLAYEY SILTY COARSE SAND AND FRACTURED LIMESTONE - SATURATED:o% <;< SS 10 12 16 25 41 SM;.:' SS i...i..:...;. 11 10 11 5 16 ...>......:... ..:...:.. -31.0 50.0 SZ 9 11 15 26 Bottom of borehole at 50.0 feet. rwre: sviaewca.n erere-erxne,, m�wao, �a 4oree. Stewart Engineering, Inc. BORING NUMBER B-4 421 Fayetteville Street, Suite 1 PAGE 1 OF 1 Raleigh, r � r Raleigh, North Carolina 2760 \\VJ/ Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSystems. Inc. PROJECT NAME MCAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5/15/08 COMPLETED 5/15108 GROUND ELEVATION 19 It BORING DEPTH 50 ft DRILLING CONTRACTOR Mid -Atlantic Drilling 0-HR GWL 81t STAB. GWL 9 ft CAVE-IN 20If DRILLING METHOD Mud Rotary AUGER SIZE 2.25-inch NOTES SS2SAMPLE NOT OBTAINED DRILL RIG CME 45 (Trailer) HAMMER TYPE Manual LOGGED BY DWB • SPT N-VALUE (BPF) zm a ❑ n 1020304050607080w O v r K W > PL MC LL > W 10203040M60 is e0N j r=- N a O 3z D ❑ FINES CONTENT (%) ❑ w W h MATERIAL DESCRIPTION ¢ Z 3 a � 0 > W ❑ N op (0 w (n o Z 10 20 30 40 50 60 20 e0 W " CONCRETE (10 INCHES) SM 5 5 6 11 ' FILL -BROWN -TAN, CLAYEY SILTY SAND - MOIST 1 ... ... """". 1... 14.5 4Ajj SOFT. BLACK AND DARK GRAY, FINE SANDY SILT WITH SOME ML _ ORGANICS -MOIST TO WET 3S 2 2 2 4 11.0 8.0 ...:..;... i...i...:..:. MEDIUM DENSE, TAN AND LIGHT GRAY, CLAYEY SILTY FINE - 5 7 8 15 ' SM SAND -SATURATED 4 ...: .i.. %...i...i...:.. i. 6.0 13. • : ...:. :..:...:...:.._..:...:...:.. MEDIUM DENSE TO LOOSE, TAN -GRAY SAND WITH SOME SILT SS 6 6 9 15 .'; AND CLAY -SATURATED 5 COLOR TRANSITIONS TO BLUE-GRAYAT -23 FEET SS 6 8 11 11 22 SP.': SM .: 7 4 6 11 17 ...:.. ..:...:...:.._ ' 0 1 1 2 :..,...,.. COLOR TRANSITIONS TO DARK GRAY @ - 26 FEET SS -15.9 34. .• SS W O R 0 .A... �......:...:. MEDIUM DENSE, LIGHT GRAY TO TAN, CLAYEY SILTY COARSE ..: . ..:...:...:..:...:...:...:. '. SAND AND FRACTURED LIMESTONE - SATURATED :'. ••••;• DRILLING FLUID LOSS AT-36 FEET "' "'^"'""?"''' SS .'. 13 13 11 24 10 . SM ... i...i... 11 -27.0 46.0 DENSE, TAN CLAYEY SILTY SAND WITH LIMESTONE FRAGMENTS ' SM -SATURATED ...:..-..=...:...=. - -31.0 50.0 12 15 14 20 34 Bottom of borehole at 50.0 feel. rive: saretw cu.w �repa-era«,.,d�waaca�w.m mmn n Operator Donald ISCoogan Cone Number DSG0867 Date And Time 5/1412008 2:40:40 PM To Job Number F8008.00 Location New River Air Station Hole Number B-5 Water Table Depth 0.00 It GPS 3443.0528N, 07726.4423W Stewart Engineering F a w REMARKS D a O Wp Tip Resistance Pore Pressure Friction Ratio SPT N• W N 03 0 Ot TSF 350 -10 Pw PSI 60 0 Fs/Ot % 8 0 60% Hammer 60 , 0 I, I 5 I � I i I I 1 I III 1 I L, L .I iIII! 1 10 I-II 15 I 20 III I I I i .III � I I I � II ! i 25 I i .._....... I III i ... ... __. .... ._ _ ....._ I I ._._.. _...._ I!III�I f'f ......... ._I.._ .........i l i i .... .._. l •. �I I �! 30 35 40 ii f .I D t - l l 17 , � sensitive fine grained ■ 4 - silty clay to clay ■ 7 - silty sand to sandy silt ■ 10 - gravelly sand to sand O 2 - organic material ■ 5 - clayey slit to silty clay O 8 - sand to silty sand 111111 - very stiff fine grained (•) 8 3 - clay 0 6 - sandy slit to clayey slit D 9 - sand 0 12 - sand to clayey sand (') Stewart Engineering, Inc. BORING NUMBER B-6 Fayetteville Street, Suite O421 Raleigh, North Carolina 27601 PAGE 1 OF 1 Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSystems Inc. PROJECT NAME MCAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5/15/08 COMPLETED 5/15108 GROUND ELEVATION 19 ft BORING DEPTH 70 It DRILLING CONTRACTOR Mid -Atlantic Drilling 0-HR GWL 9.5 it STAB. GWL 10 ft CAVE-IN 22 It DRILLING METHOD Mud Rotary AUGER SIZE 2.25-inch NOTES DRILLRIG CME 45 (Trailer) HAMMER TYPE Manual LOGGED BY DWB x ♦ SPT N-VALUE (BPF) Z m a 10 20 30 40 50 BD 70 80 90 PL MC LL c > r m w w > w Q = N U n ~ D 10 20 30 400 80 90 ❑FINES CONTENT (%) ❑ w 0 MATERIAL DESCRIPTION < m 3: N m O Z o C 10 20 30 40 60 80 70 80 90 C CONCRETE (61NCHES) SS 8 9 9 18 SM 1 SS 4 4 4 8 """"""""""""""" "' "" FILL - TAN CLAYEY COARSE SAND - MOIST FILL - GRAY AND BROWN, CLAYEY SILTY SAND - MOIST 13.5 5.5 SS 10 10 10 20 .:...:...:... ' SM ' ' : ' MEDIUM DENSE, DARK GRAY SILTY FINE SAND WITH TRACE 11.0 8.0 �' ROOTLETS - MOIST TO WET 3 SS 0 0 1 1 ...:. .: ..:...:...>...;..;...;...;.. VERY SOFT, DARK GRAY SANDY SILTY CLAY - SATURATED CH 4.5 14. SS S 0 1 10 11 .. ...:..;... i...i........i. MEDIUM DENSE TO VERY LOOSE, GRAY SAND WITH SOME SILT AND CLAY -SATURATED ... ............. `........'. SS 4 5 5 10 SS 4 11 12 23 °...................:...:. SP ' :. ...:.. :...:...i...i...:..:...i...i.. SM ' .:' SS 8 1 1 0 1 ...'...;..:...:...:...:.. ;. '. SS 9 1 1 1 2 .....:..:...�...; ..:... -19.0 38.0 SS 14 18 20 38 ' MEDIUM DENSE TO DENSE, TAN -GRAY, CLAYEY SILTY COARSE SAND AND FRACTURED LIMESTONE - SATURATED 70 ...`..:...1..>' .': SS it 14 8 9 17 ...;..: "t...i...i.....i...i...i. .;. ::. SS 12 11 13 21 34 : . - - . ...i...:..: .i...i...:..:... i. ONLY TRACE LIMESTONE FRAGMENTS BELOW -50 FEET SM:.;: ...:..:...:... ..:..::..:......:.. ' SS 13 29 18 35 53 ...:.. _..:...:.....:..:...:...:.. 'X SS 9 9 9 18 ' _......:...:.. 14 ...:.. ..:...:...:.. 15 16 23 25 48 48.0 67.101 ........................:... i...i... SM'• ' ' ' DENSE, OLIVE -TAN, SILTY FINE SAND WITH TRACE SHELLS AND -51.0 70.0 TRACE LIMESTONE FRAGMENTS - SATURATED 16 12 45 25 70 Bottom of borehole at 70.0 feet. Abre: Sa7�6n av��alrerx{u� kA e y ?' Operator Donald B Coogan Cone Number DSG0867 Date And Time 5/14/2008 5:31:03 PM to s Job Number F8008.00 Location New River Air Station Hole Number B-7 co Water Table Depth 0.00 ft GPS 3443.0350N, 07726.5076W M A" . ao v +' Operator Donald B Coogan Cone Number DSG0867 Dale And Time 5/14/2008 4:45:57 PM J. Job Number F8008.00 Location New River Air Station Hole Number B-8 aA o co Water Table Depth 0.001t GPS 3443.0395N, 07726.4588W Of Stewart Engineering a W REMARKS o a O pr Tip Resistance Pore Pressure Friction Ratio SPT N' w � 0] 0 Ot TSF 300 -15 PW PSI 40 0 FslOt M 5 0 60%Hammer 60 , 0 T i r ... 5 ...«.. I .. 10 15 20 i 25 ._I .. ..... .. '..._ ...... .. .. ........... i i 30 7_1 _. II i 35 40 0 1 - sensitive fine grained ■ 4 - silty clay to clay ■ 7 - silty sand to sandy silt ■ 10 - gravelly sand to sand 0 2 - organic material ■ 5 - clayey silt to silty clay 0 8 - sand to silty sand ■ 11 - very stiff fine grained (•) ■ 3 - clay 0 6 - sandy silt to clayey silt 0 9 - sand 11112 - sand to clayey sand (•) MAD �e iV Operator Donald B Coogan Cone Number DSG0867 Date And Time 5/14/2008 3:49:51 PM r•Job Number F8008.00 Location New River Air Station Hole Number B-9 co Water Table Depth 0.00 ft GPS 3443.0387N, 07726.4036W tY Stewart Engineering Q W REMARKS EL dxa pTip Resistance Pore Pressure Friction Ratio SPT N' 0 W 0 Ot TSF 300 -10 Pw PSI 30 0 Fs/Qt % 9 0 60% Hammer 50. 0 I 17i 510 I 15 20 25 ..,. ............. .......... ... .. ............. ...........,.... .... ......... i .. ........:. .._.... .......' ... 30 I i , 35 L....... I I . I �....._ ... ...... ... ... i.. L......I 1 1 1 ..L.....,j. I I ..._.. 1 ,. I j 40 I L..... I ;-..... . .1 .:.. .... ... ... ..; .... _. .. .I_.._..� ... .i.......;. l ...... I_. .I ..... . _.. D 'I - • sensitive fine grained ■ 4 - silty clay to clay ■ 7 - silty sand to sandy silt ■ 10 - gravelly sand to sand D 2 - organic material ■ 5 - clayey silt to silty clay ❑ 8 - sand to silty sand N 11 - very stiff fine grained (') 03. clay 8 6 - sandy slit to clayey silt 09. sand 0 12 - sand to clayey sand (') Stewart Engineering, Inc. BORING NUMBER PLA 421 Fayetteville Street, Suite 400 i Raleigh, North Carolina 27601 PAGE 1 OF 1 OS Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSystems. Inc. PROJECT NAME MCAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5/16/08 COMPLETED 5/16108 GROUND ELEVATION 13 it BORING DEPTH 10 ft DRILLING CONTRACTOR Mid -Atlantic Drilling 0-HR GWL 6 it STAB. GWL CAVE-IN 10 ft DRILLING METHOD Mud Rotary AUGER SIZE 2.25-inch NOTES Elevation assumed -no survey data available at time of exploration DRILL RIG CME 45 (Trailer) HAMMER TYPE Manual LOGGED BY DWB ♦ SPT N-VALUE (BPF) m a o n 10203040 W 807080w O w > w PL MC LL > wa w w rn z Q 2---0 10 20 80 40 58 80 78 80 W ❑ FINES CONTENT 1%) 0 w w w MATERIAL DESCRIPTION z N m 0 i r020 W 40 s9 ro]08090 O — TOPSOIL (8 INCHES) SS ' ' ' ' ' ' ' ' OL FIRMTOVERY SOFT, BLACK, SANDY ORGANIC SILT - MOIST TO 1 1 3 3 6...i...:..:...:...:...:..;......i. — WET SS ..;...;..;... i...;...;..;......;.. 2 0 VERY SOFT, GRAY AND TAN, SILTY CLAY - WET TO SATURATED SS Q ..... _........... .._....... . 25 CH 3 31 1 2 3.0 10.0 4S 1 1 1 2 Bottom of borehole at 10.0 feet. Here: sPreuw cw�mereo4r8 rya wasan� n� �e Operator Donald B Coogan Cone Number DSG0867 Date And Time 511412008 6:15:54 PM Job Number F8008.00 Location New River Alr Station Hole Number PL•2 V Water Table Depth 0.00 ft GPS 3443.1060N, 07726.4272W Stewart Engineering a F w REMARKS a owo wp r Tip Resistance Pore Pressure Friction Ratio SPT N` /n 03 0 Ot TSF 100-10 Pw PSI 30 0 Fs/Ct % 6 0 60%Hammer 18 12 0 iII I l I Ill I',Il' 2 '. J.....i.. I .... L... ..... .. � .' _... .__..... ........I :.......i III it I I I l I I II '�!I� iII �II I I I I III' 10 I,, I III I I I I I I I I I !!I i�'ll'III I 0 1 - sensitive fine grained ■ 4 - silty clay to clay ■ 7 - silty sand to sandy slit ■ 10 - gravelly sand to sand 132 - organic material ■ 5 - clayey slit to silty clay 0 8 - sand to silty sand M 11 - very stiff fine grained (') ■ 3 - clay 0 6 - sandy silt to clayey silt 0 9 - sand 0 12 - sand to clayey sand (`) Ei Stewart Engineering, Inc. BORING NUMBER PL-3 Fayetteville Street, Suite Ral NorthPAGE 1 OF 1 Raleigh, NOCarolina 27601 C Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TmnSystems, Inc. PROJECT NAME MCAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5116/08 COMPLETED 5/16108 GROUND ELEVATION 14 it BORING DEPTH 10 ft DRILLING CONTRACTOR Mid -Atlantic Drilling 04IR GWL 5 H STAB. GWL CAVE4N 10 ft DRILLING METHOD Mud Rotary AUGER SIZE 2.25-inch NOTES Elevation assumed - no survey data available at time of exploration DRILLRIG CME 45 (Trailer) HAMMER TYPE Manual LOGGED BY DWB ♦ SPT N-VALUE (SPF) A m a 6 10 20 30 40 W 607060 W O v > w > n PL MC LL ~ to ww m j y 3 w 10 20r00 40 W 60 70 r60 W El FINES CONTENT (%) ❑ w w m MATERIAL DESCRIPTION Z a O ? w O D to o6 (7 w m u 2 10 20 00 40 50 60 70 60 90 1.1 L TOPSOIL (8 INCHES)SS SC ' LOOSE, TAN, CLAYEY FINE SAND - MOIST 1 1 3 2 5 ...:...: ..:...:...:..;...;...;. 0.5 5.5 SS 2 Q 2 1 3 4 ......... :........................ MEDIUM DENSE, LIGHT GRAY, SILTY FINE SAND - SATURATED SS 3 4 8 7 15 VERY SOFT, DARK GRAY, SILTY CLAY - SATURATED SS 6.5 7.5 SM t'. CH 4.0 10.0 4 W 0 H 0 Bottom of borehole at 10.0 feet. ride: Svrflew ca�naereadfi`w;aa Stewart Engineering, Inc. BORING NUMBER PL-4 Fayetteville Street, Suite 1 PAGE 1 OF 1 Raleigh, North Carolina 2760 O Raleigh, Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSystems Inc. PROJECT NAME MICAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5116/08 COMPLETED 5116108 GROUND ELEVATION 15 it BORING DEPTH 10 ft DRILLING CONTRACTOR Mid -Atlantic Ddllinq 04HR GWL 51t STAB. GWL CAVE-IN 10 ft DRILLING METHOD Mud Rotary AUGER SIZE 2.25-inch NOTES Elevation assumed - no survey data available at time of exploration DRILL RIG CME 45 (Trailer) HAMMER TYPE Manual LOGGED BY DWB A SPT N-VALUE (BPF) zm d ❑ n 10 20 Wd0 50 W]0 BO 90 PL MC LL O w > Q _ NCe U 3 w J 10 20 30 401 0 80 70t80 90 ❑ FINES CONTENT (%) ❑ w y MATERIAL DESCRIPTION Q z 3 a o > w ❑ D W o (0 N m U z 10 20 30 40 50 50 70 80 90 ' TOPSOIL (8 INCHES) SS ' 3 2 2 4 SOFT TO FIRM, TAN TO GRAY, SANDY SILTY CLAY - MOIST TO 1 """""""""""' ...... CHVIA WET SS ° ' 9.5 5.5 2 1 2 4 6............:................... VERY LOOSE, TAN, COARSE SAND - SATURATED SS ..=................ ........ 3 222 4 VERY SOFT, DARK GRAY, SILTY CLAY - SATURATED SS f f 7.5 7.5 SP ' ":'. CH 5.0 10.0 4 W O R 0 Bottom of borehole at 10.0 feet. d :S Ta Caws ere W6F dp b W aererx4vs edeE. Operator Donald B Coogan Cone Number DSG0867 Date And Time 5/14/2008 6:32:11 PM A v. �n ' Job Number F8008.00 Location New River Air Station Hole Number PL-5 bo Water Table Depth 0.00 It GPS 3443.1689N, 07726.4537W Of Stewart Engineering a W REMARKS a p V Tip Resistance Pore Pressure Friction Ratio SPT N. wo o0 m 0 Ot TSF 50.10 Pw PSI 25 0 Fs/Ol % 6 0 60%Hammer 14, 0 2 I i II 4 i III I i...... II ... _,....... .. 8 i�Il�lli D 1 - sensitive One grained ■ 4 - siltyclay to clay ■ 7 - silty sand to sandy slit ■ 10 - gravelly sand to sand D 2 - organic material ■ 5 - clayey slit to silty clay G 8 - sand to silty sand ■ 11 - very stiff One grained (') ■ 3 - clay 0 6 - sandy silt to clayey silt D 9 - sand 0 12 - sand to clayey sand (•) Stewart Engineering, Inc. BORING NUMBER SDA A 421 Fayetteville Street, Suite 400 Raleigh, North Carolina 27601 PAGE 1 OF 1 J` Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TmnSystems, Inc. PROJECT NAME MCAS Aircraft Maintenance Hangar PROJECT NUMBER F8008.00 PROJECT LOCATION Jacksonville, NC DATE STARTED 5/16/08 COMPLETED 5116108 GROUND ELEVATION 15 ft BORING DEPTH 10 ft DRILLING CONTRACTOR Mid -Atlantic Drilling 0-HR GWL 5 ft STAB. GWL CAVEaN 10 ft DRILLING METHOD Mud Rotary AUGER SIZE 2.254nch NOTES Elevation assumed -no survey data available at time of exploration DRILL RIG CME 45 (Trailer) HAMMER TYPE Manual LOGGED BY DWB ♦ SPT N-VALUE (BPF) m w (1 n 10203040 M W 70 WW PL MC LL p v Y w j w n w j vNi aj 3z < 1020304� 70 SO ❑FINES CONTENT (%) ❑ o W MATERIAL DESCRIPTION ro N m O i w 1020304050W 70 fi0 W O SC TOPSOIL (8 INCHES) SS 1 2 2 4 VERY LOOSE, TAN, CLAYEY FINE SAND - MOIST 1 "''"""""""""""""""' FIRM TO VERY SOFT, LIGHT GRAY, SILTY CLAY -MOIST TO 2S 1 2 3 5 Q ' ''"''" ... . . . !" . 11.5 3.5 SATURATED - .. . .....:...:...:.......:. -" CH 3s 1 1 2 3 i. 5.0 10.0 ..i..:..•;...;..•i.. •y..;... aS 1 1 1 2 Bottom of borehole at 10.0 feet. Nae: spratw cww��.sna�d�buaru,�ouar»+mnaee. Stewart Engineering, Inc. OSSteteFayetteville Street, Suite 400 Raleigh, North Carolina 27601 Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSvstems Inc. PROJECTNUMBER F8008.00 S- c 0 N W 30............................................................................... 20..81 .......... ........... ..................... .......................... e<. 9 4 5 10 .. . ........... ................. .... ....................... 3 ..........: 17 ,_...............................................................: t........ 18 28 SUBSURFACE PROFILE Figure No.:3 PROJECT NAME MCAS Aircraft Maintenance Hangar PROJECT LOCATION Jacksonville NC ............................................................................................................................. ....................................................... B-3 .................................................................. 17 12 5 ......................................................IM* 5............................................................... 9 ......................................................24.............................................................. 16 ......................................................7............................................................... 3 .................................................................................................16 ................................................................................................................... ............................................................................................................................. ............................................................................................................................. Distance Along Baseline REFER TO FIGURE 5 FOR LEGEND Stewart Engineering, Inc. 421 Fayetteville Street, Suite 400 Raleigh, North Carolina 27601 Telephone: 919-380-8750 Fax: 919-380-8752 CLIENT TranSysterns. Inc. PROJECT NUMBER F8008.00 C 0 LLI 2 2 SUBSURFACE PROFILE Figure No.A PROJECT NAME MICAS Aircraft Maintenance Hangar PROJECTILOCATION Jacksonville, INC ....................................................................................................................... ....................................................................................................................... PL4 ........................................ . . . ................................................................... P L 3 ....................................... .................................................................. . . 4 Distance Along Baseline REFER TO FIGURE 5 FOR LEGEND Material Description * Poorly graded sand with silt SP-SM * Poorly graded sand with silt SP-SM * Poorly graded sand with silt SP-SM Project No. F8008.00 Client: TranSysterns, Inc. Remarks: Project: MCAS Aircraft M * Location: B I Depth: 18.5-20 Sample Number: S6 * Location: B I Depth: 23.5-25 Sample Number: S7 * Location: B I Depth: 28.5-30 Sample Number: S8 Stewart Engineering, Inc. Raleigh, NC Figure Tested By: FAR Project No. F8008.00 Client: TranSysterns, Inc. Project: MCAS Aircraft Maintenance Hangar o Source ofSample: BI . Depth: 33.5-35 Sample Number: S9 Stewart Engineering' Inc. Raleigh, NC Tested By: Material Description 0 Poorly graded sand with silt io Silty sand with limestone fragments Project No. F8008.00 Client: TranSystems, Inc. Remarks: Project: WAS Aircraft Maintenance Hangar * Location: B3 Depth : 23.5-25 Sample Number: S7 * Location: 133 Depth: 38.5-40 Sample Number: SIO Stewart Engineering, Inc. Raleigh, NC Fi Tested By: • John Creech ■ JC IM M. iiiiiiiisillillimmillililimililillin Material Description o gaded sand with silt Project No. F8008.00 Client: TrunSystents, Inc. Remarks: Project: MCAS Aircraft Maintenance Hangar o Source of Sample: 134 Depth: 33.5-35 Sample Number: S9 Stewart Engineering, Inc. -Raleigh, NC Figure L-4 Tested By: JC Material Description * Poorly graded sand with silt * Poorly graded sand with silt Project No. F8008.00 Client: TranSysterns, Inc. Remarks: Project: MCAS Aircraft Maintenance Hangar * Source of Sample: B6 Depth: 13.5-15 Sample Number: S5 * Source of Sample: 136 Depth: 23.5-25 Sample Number: S7 Stewart Engineering, Inc. Raleigh, NC Figure Tested By: JC LIQUEFACTION ANALYSIS New Aircraft Maintenance Hangar Hole No.=B-1 Water Depth=8.5 It Surface Elev.=19 Magnitude=6.76 Acceleration=.0873g Sheer Stress Redo Fectoro/Sehy S.Mement Soll Descnpnon Raw unit Fines !M 0 t 0 1 5 0(in) 10 SPTWeIghl % 0 9 120 20 1111 T SILTY SAND q NoLq SANDY CLAY C7 — SAND WITH SILT AND CLAY 10 . 3 6 � %,j•J1 17 6 20 zD 6 80'•''•'�• 1 10 M1 3 8 �.,' SILTY SAND AND FRACTURED 40 LIMESTONE 28 15 I 18 15 50 i' 21 15 E 8 e 65 15 i S —60 20 15 pSe 5 28 15 p 70 1.1.00-� S = 3.76In. 4] 15 SaNrehd — F C R — CSR h1 — $ Shaded Zone has Llquetacdun Polendal ur..Wnat. MCAS New River, NC LIQ1 l51}STEWART ENGINEERING, INC. LIQUEFACTION ANALYSIS New Aircraft Maintenance Hangar Hole No.=B-3 Water Depth=8 R Surface Elev.=19 Magnitude=6.76 Acceleration=.0873g Sheer Shoes Ratio Factor of Safety Selllerrent Sall Description Rew Unit Fines (IQ 0 1 0 1 5 OfInJ 1° SP71z We1z8l h140 % '-'�TRT CLAYEY SAND wrrN CLAY rocKers ° I+'�� 12 40 j SANDY CLAY i 5 NOLq 10 i SANDY CLAY CLAYEY SA CLAYEYND s zD SAND WRR SLT AND CLAY L 20 24 5 "( 16 5 (•'ii F[ JO:, 7 5 Ff ;•�;i 3 5 SILTY SAND AND FRACTURED LNIESTONE 16 14 I 11-1.00 S = 1.29 In. 50 28 14 CRR — CSR Isf� Sewreied — Shaded Zone has Liquefaction Potential Unethical. — �k --60 6 i g 70 NICAS New River, NC L102 l J N STEWART ENGINEERING, INC. 0 0 LIQUEFACTION ANALYSIS New Aircraft Maintenance Hangar Hole Ho. B-4 Water Depth=8.5 ft Surface Elev.=f9 Magnitude=6.76 Acceleration=.0873g shear Stress Ratio Factor f Safety Sedler,ent Soil Description in) 0 0 t o 1 5 0 (in.)m ..... . SLTY SAM I� SANDY SLT — SLTY SAND 10 I I � N'%'%,•`w SANOWRNSLTANOCLAY L20 30 SLTY SANG AM FRAMN I. LWSTONE a0 i z— _— I is •L00 S•4.29 In. �so CRR — CSR Isf— Sat..I.d — jr $haded Zone has Liquefaction potential unseturaL — YraS)O r. 60 A 5_ F i 70 —— — — -----____. MCAS New River, NC —---_----LIQ3 lJ),'STEWART ENGINEERING, INC. LIQUEFACTION ANALYSIS New Aircraft Maintenance Hangar Hole Ho =B-6 Water Depth=8.5 It Surface Elev.=19 Magnitude=6.76 Acceleration=.0873g Sheer Stress Ratio Factor of Win, Sells.." Soil Description Re sr Unit Fines (R) 0 1 0 1 5 0 on.) 10 SPT 4Ve: hl % 0 i� CLAYEY -SA 18 ,z8 30 � a 30 i SANDY CLAY 10 I 1 NOLp SAND 11 5 I 10 10 5 SAND 3 23 5 L I M CLAYEY SAND C30 1 5 2 5 I 10 � ' -'. 38 15 17 15 — i 50 i 34 15 i 53 15 eo 48 15 SLTY SAND 1.1.00 s•e.ao in. g Ta TD is CRR — CSR 1.1Saturated = Shaded zone has Liquefaction Potential Unsawre:. MCAS New River, NC LIQ4 l' It STEWART ENGINEERING, INC. PROBABILISTIC SEISMIC HAZARD DEAGGREGATION b Prob. Seismic Hazard Deaggregation roe MCAS_New_River 77.441° W, 34.717 N. N Peak Horiz. Ground Accci.>-0.08737 g Mean Return Time 2175 yews Mean (R,M,Ep) 172.2 km, 6.76. 0.45 0 N Modal (R,M,E,) - 232.3 kin, 736. 0.70 (from peak R.M bin) Modal (R,M,e-) —2324 km, 736, 1 to 2 sigma (from peak R,M,E CO Binning: DeltaR 25. km, deltaM-0.2. DeltaE=1.0 1: J m ti C s <maElan I RN >mtlion ea<.2 r-_'<CO<-1 0<ea<0.5�� �T �� a 0.5<ca<l\� 0-1<%<-0.5 n I<ea<" 0 ?<r,<3 Cr 010.5 <ea <0 0 1.5 <f0<2 2W3 update USGS PSWI ®xmr.I±ry,o.nau® .....-...,...n nn.. COIr . w.. YM�InI,O��ta�IGaue,e SPECTRAL ACCELERATION VALUES Conterminous 48 States 2003 NEHRP Seismic Design Provisions Latitude = 34.717289 Longitude =-77.440938 Spectral Response Accelerations Ss and S1 Ss and S1 = Mapped Spectral Acceleration Values Site Class B - Fa = 1.0 ,Fv = 1.0 Data are based on a 0.05 deg grid spacing Period Sa (sec) (g) 0.2 0.204 (Ss, Site Class B) 1.0 0.076 (S1, Site Class B) Conterminous 48 States 2003 NEHRP Seismic Design Provisions Latitude = 34.717289 Longitude =-77.440938 Spectral Response Accelerations SMs and SM1 SMs = FaSs and SM1 = FvS1 Site Class D - Fa = 1.6 ,Fv = 2.4 Period Sa (sec) (g) 0.2 0.326 (SMs, Site Class D) 1.0 0.183 (SM1, Site Class D) Conterminous 48 States 2003 NEHRP Seismic Design Provisions Latitude = 34.717289 Longitude =-77.440938 SDs = 2/3 x SMs and SD1 = 2/3 x SM1 Site Class D - Fa = 1.6 ,Fv = 2.4 Period Sa (sec) (g) 0.2 0.217 (SDs, Site Class D) 1.0 0.122 (SD1, Site Class D) N L a a> IN Lateral Deflection vs. Depth Deflection, in. 0 0.2 0.4 0.6 0.8 1 = 1-inch deflection — 12-inch deflection —114-inch deflection LPILE Plus 5. 0, (c) 2007 by Ensoft Inc. w Shear Force vs. Depth Shear Force, kips -5 0 5 10 ------------------------- —1-inch deflection —12-inch deflection — 114-inch deflection LPILE Plus 5.0, (c) 2007 by EnsoR, Inc. Bending Moment vs. Depth Bending Moment, kips -in. 0 200 400 600 —1-inch deflection — 112-inch deflection —114-inch deflection LPILE Plus 5. 0, (c) 2007 by Ensoft Inc. 12-inch PCPS Concrete Piles V Lateral Deflection vs. Depth Deflection, in. 0 0.2 0.4 0.6 0.8 1 i 9 ------------------------- — 1-inch deflection — 1f2-inch deflection — 1I4-inch deflection LPILE Plus 5.0, (c) 2007 by EnsoR, Inc. Shear Force vs. Depth Shear Force, kips -10 -5 0 5 10 15 — 1-inch deflection —1 f2-inch deflection — 1l4-inch deflection LPILE Plus 5.0, (c) 2007 by EnsoR, Mc. Bending Moment vs. Depth Bending Moment, kips -in. 0 200 400 600 800 1.00 — 1-inch deflection — 1!2-inch tleflecion — 1/4-inch deflection LPILE Plus 5. 0, (c) 2007 by EnsoR, Inc. 14-inch PCPS Concrete Piles CJ UNIFIED SOIL CLASSIFICATION (ASTM D-2487) MATERIAL CRITERIA FOR ASSIGNING SOIL GROUP NAMES GROUP SOIL GROUP NAMES & LEGEND TYPES SYMBOL GRAVELS CLEAN GRAVELS ac C°><AND I<3 GIN WELL -GRADED GRAVEL •a• Cu><AND 1>U>3 GP POORLY -GRADED GRAVEL >50% OF COARSE <5% FINES p z O FRACTION RETAINED O NO w j ON NO 4. SIEVE GRAVELS WITH FINES FINES CLASSIFYa AS ML OR GM SILTY GRAVEL p ^d > 12% FINES Z4W 0 FINES CLASSIFY AS CL OR CH GC CLAYEY GRAVEL 0 SANDS CLEAN SANDS CV>6 AND I<U,3 SW WELL -GRADED SAND O W o z <5% FINES Cu>6 aN01>Q>3 SP POORLY -GRADED SAND < n >50% OF COARSE FINES CLASSIFY AS ML OR SM SILTY SAND 00 FRACTION PASSES ON NO 4. SIEVE SANDS AND FINES >12%FINES FINES CLASSIFY AS CL OR CH SC CLAYEY SAND SILTS AND CLAYS PI>z AND Mors>'A•LINE CL LEAN CLAY INORGANIC OO LIQUID LIMIT<50 PI>4 AND <v UNE ML SILT w j wain zao ORGANIC u(oren dflMVU-(mt drMn)<o.75 OL ORGANIC CLAY OR SILT = _ -- 4n. ^I SILTS AND CLAYS PI PLOTS > a• LINE CH FAT CLAY l7 l0n p INORGANIC WAz LIQUID LIMIT>50 MPILOTS <•A•UNE MH ELASTIC SILT ORGANIC u(o.m aH•e)/u I. dHeo)<o.zs OH ORGANIC CLAY OR SILT HIGHLY ORGANIC SOILS PRIMARILY ORGANIC MATTER, DARK IN COLOR, AND ORGANIC ODOR PT PEAT — — SAMPLE TYPES OTHER MATERIAL SYMBOLS ' POOdy Graded Sand Sand SAM Spoon with Clay Clayey Sand Silt Sandy Silt Well Graded Gravelly Sand Low to High Plasticity ClayGravelly SiltADDITIONAL i ABBREVIATIONS &SYMBOLS Poorly Gaded Gavelly SanAsphalt SPr - srANDARD PENETRATION TEST L—� _ O.HR GROUNDWATER LEVEL BFP - BLOWS PER FOOT > =: Topsoil Boulders and Cobble M. P C UNIT U- - LIQUID LIMIT SFABN2ED GROUNDWATER LEVEL MC - MOISTURE CONTEM Well Gaded Gavel • with Clay SS - SPLIT SPOON PLO CAVE-IN LEVEL J� GWL GROUNDWATER LEVEL (AT LAST OWL READING) Well Graded Gravel USES- UNITED SOIL CLASSIFICATION SYSEM • with Silt WON - WEIGHT OF HAMMER WO0. - WEIGHT OF RODS PLASTICITY CHART BO ro W f p CL w F1 ONBMN d A P 10 ML OL 0 NUMBER OF BLOWS OF 140 LB HAMMER FAIIJNG 30 INCHES TO DRIVE A 21NCH CO. D 10 A 30 40 50 AD 70 so BE LEE 110 Im (1-3/8 INCH I.O.)SPLIT-EVAREL SIMPLER THE LAST 12 INCHES OF AN IO-INCH DRIVE LIQUID LIMIT(%) (ASTM-I5B6 STANDARD PENEIMTION TEST). Stewart Engineering, Inc. LEGEND TO SOIL Figure Numbe � / DESCRIPTIONS 5 Job No. F8008.00 PENETRATION RESISTANCE (RECORDED A5 BLOWS / 0.5 F7) (RECORDED SAND 6 GRAVEL a CLAY COMPRESSIVE RELATIVE DENSITY BLOWS/FOOT' CONSISTENCY BLOWS/FOOT' STRENGTH (TSF) WHY LOOSE o-4 VERY soFr o-z D-0.2s LOOSE S. m soFr 3-4 o.z6-os0 MEDIUM 0EN5E I1-30 MEDIUM STIFF (FIRM) 5-B 0.53-1.0 OF1SE II-50 STIW 9-t5 L1-3.0 VEM OE115E OVER VERY STIFF I6-30 3.1 -i.0 HARn OVER 30 OVER 4.0 V-1. 5�8 080 (o53 North Carolina Department of Environment and Natural Resources A7A Request for Express Permit Review NCDENR For DENR Use ONLY Reviewer: G 13 Submit Time: Confirm}.rt- FILL-IN all the information below and CHECK the Permit(s) you are requesting for express review. FAX or Email the completed form to Express Coordinator along with a completed DETAILED narrative, site plan (PDF file) and vicinity map (same items expected in the application package of the project location. Include this form in the application package. • Asheville Region -Alison Davidson 828-296-4698;alison.davidson(dncmail.net • Fayetteville or Raleigh Region -David Lee 919.791-4203; david.lee(a)ncmail.net • Mooresville & -Patrick Grogan 704-663.3772 or patrick.grogan(&.ncmail.net • Washington Region -Lyn Hardison 252-946-9215 or lyn.hardison(cDncmail.net • Wilmington Region -Janet Russell 910-350-2004 or ianet.russell(dncmail.net NOTE Project application received after 12 noon will be stamped in the following work day. I Project Name: MICAS NEW RIVER AIRCRAFT MAINTENANCE HANGAR County: ONSLOW Applicant: CARL BAKER Company: MCB CAMP LEJEUNE, DESIGN BRANCH PUBLIC WORKS DIVI Address:1005 MICHAEL ROAD City: CAMP LEJEUNE, State: NC Zip: 28547 D E C E I V E D Phone:910-451-2213 Fax:910-451-2927 Email: cad.h.baker(ausmc.mil Project is Drains into SC waters Project Located in NEW RIVER River Basin JUL 14 2008 Engineer/Consultant: RYAN HAMBLETON Company: STEWART ENGINEERING, INC Address: 421 FAYETTEVILLE ST. SUITE 400 City: RALEIGH, State: NC Zip: 27603 DWQ Phone: 919-866-4819 Fax::919-380-8752 Email: Rhambleton(u)Stewart-eng.com PROJ k (Check all that apply) ❑ Scoping Meeting ONLY ® DWQ, ❑ DCM, ® DLR, ❑ OTHER: ❑ Stream Origin Determination: # of stream calls — Please attach TOPO map marking the areas in questions ® State Stormwater ® General ❑ SFR, ❑Bkhd & St 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 2 # Treatment Systems ❑ High Density —Constructive Wetlands _ # Treatment Systems ❑ High Density -Other _ # Treatment Systems ❑ MODIFICATION SW _ (Provide permit #) ❑ Coastal Management ❑ Excavation & Fill ❑ Bridges & Culverts ❑ Structures Information ❑ Upland Development ❑ Marina Development ❑ Urban Waterfront ® Land Quality ® Erosion and Sedimentation Control Plan with 10.3 acres to be disturbed.(CK # (for DENR use)) WETLANDS QUESTIONS MUST SE ADDRESSED BELOW ❑ Wetlands (401): Check all that apply Wetlands on Site ❑ Yes ® No Wetlands Delineation has been completed: ❑ Yes ❑ No US ACOE Approval of Delineation completed: ❑ Yes ❑ No 404 Application in Process w/ US ACOE: ❑ Yes ❑ No Permit Received from US ACOE ❑ Yes ❑ No Fee Split for multiple permits: (Check # Isolated wetland on Property ❑ Yes ❑ No Buffer Impacts: ❑ No ❑ YES: acre(s) Minor Variance: ❑ No ❑ YES Major General Variance ❑ No ❑ YES 401 Application required: ❑Yes ❑ No If YES, ❑ Regular Perennial, Blue line stream, etc on site ❑ yes ❑ No For DENR use only Total Fee Amount $ SUBMITTAL DATES I Fee I SUBMITTAL DATES Fee CAMA $ Variance ❑ Ma'; ❑ Min $ SW ❑ HD, ❑ LID, ❑ Gen $ 401: $ Los $ Stream Deter,_ $ Cup;C'6' +b Cook 0r\ 9'3-05 RE: Express Info Subject: RE: Express Info From: "Ryan Hambleton" <rambleton cr stewart-eng.com> Date: Fri, l 1 Jul 2008 17:21:09 -0400 To: "Janet Russell" <Janet. Russelln ncmail.net> Janet, I am sending you this express review request for the New River Hangar Project. I am including only the express review application as I have already sent the narrative and map with the scoping meeting request. Please let me know if there is anything else you need to set the meeting up. Also - I have a couple questions on applications and where I can get submittal requirements for the express review to ensure I bring everything. Please try for a start time after loam or before 3pm on the following dates; July 22nd July 23rd OR in the morning between 9am and llam on July 24th or 25th Ryan -----Original Message ----- From: Janet Russell[mailto:Janet.Russell@ncmail.net) Sent: Thursday, June 19, 2008 5:32 PM To: Ryan Hambleton Subject: Express Info Ryan: To get into the Express Program, please submit the Express Request, complete stormwater narrative, vicinity map, and pdf site plan (if available). This gets you scheduled. Also, indicate any dates/times that you are not available in the next couple of weeks. For Onslow County, a phase II county, the Session Law outlines the design criteria which is more strict that the non -Phase II counties. Start reading around page 13. It is attached. You can request a "scoping" meeting if you feel you need one or go straight for the submittal meeting. At a submittal meeting, we won't take an incomplete application package anyway and it could turn into a "scoping" meeting. Janet Russell Express -Coordinator 910 796-7421 Content -Description: Express Review Request (New River Hangar).doc Express Review Request (New River Hangar).doc Content -Type: application/msword Content -Encoding: base64 I of 1 7/11/2008 5:38 PM .. . >- a- I.. X si e�' -05 f :j III. �. i �i �� � � III �� �� i i ,,_ '. �I iii...._ ''. iI ! I !,'il New River Hanger Subject: New River Hanger From: 'Joe Puckett" <jpuckett@stewart-eng.com> Date: Thu, 10 Jul 2008 17:02:11 -0400 To: <christine.nelson@ncmail.net> CC: "Ryan Hambleton" <rhambleton@stewart-eng.com> Christine, We met with you about the New River Hanger at Camp Lejeune earlier this week. Attached is a pdf of how we plan to divert the stormwater in excess of the design volume to a filter strip. Would you have a few minutes to look at this sketch and discuss any issues with this design on the phone? Thank you in advance. Joe Puckett, PE, LEEDA AP Project Engineer STEWART 421 Fayetteville Street, Suite 400 Raleigh, NC 27601 T 919.380.8750 x229 F 919.380.8752 D 919.866.4829 Engineering, Innovation. Solutions. PPlease consider the environment before printing this email Content -Description: Hanger SWM.pdf Hanger SWM.pdf Content -Type: application/octet-stream Content -Encoding: base64 I of 1 7/16/2008 8:35 AM MCAS New River Aircraft Maint. Manger Subject: MCAS New River Aircraft Maint. Hanger From: Carol Miller <Carol.MiIler@ncmail.net> Date: Thu, 10 Jul 2008 08:29:12 -0400 To: Janet Russell <Janet.Russell@ncmail.net> Janet, please let me know when they get this scheduled as the will want to do the E&SCP at the same time. thx! I of 1 7/10/2008 8:33 AM RE: New River Aircraft Maintenance Hangar Subject: RE: New River Aircraft Maintenance Hangar From: "Ryan Hambleton" <rhambleton@stcwart-eng.cotn> Date: Sun, 29 Jun 2008 10:40:28 -0400 To: "Janet Russell" <Janet.Russell@ncmail.net>, "Towler GS05 David W" <david.towler cr usme.mil> I am confirming the Express Stormwater submittal scoping meeting (aka pre -express review meeting) for Tuesday, July 8th at 1:30pm with Christine Nelson. Ryan -----Original Message ----- From: Janet Russell[mailto:Janet.Russell@ncmail.net] Sent: Thursday, June 26, 2008 6:21 PM To: Ryan Hambleton; Towler GS05 David W Subject: New River Aircraft Maintenance Hangar June 26, 2008 *New River Aircraft Maintenance Hangar* Gentlemen: The Express Stormwater submittal meeting has been scheduled with *Christine Nelson on July 8, 2008 at 1:30 PM* here in the Wilmington Regional Office, 127 Cardinal Drive Ext., 28405. Please review the submittal requirements, attached. Note that we prefer plans folded to fit into the file system, 9" x 14" . Please respond within 2 business days to confirm and reserve the submittal meeting date. Thanks, Janet Russell Express Coordinator I of 1 6/30/2008 2:10 PM aboutblank June 26, 2008 New River Aircraft Maintenance Hangar Gentlemen: The Express Stormwater submittal meeting has been scheduled with Christine Nelson on July 8, 2008 at 1:30 PM here in the Wilmington Regional Office, 127 Cardinal Drive Ext., 28405. Please review the submittal requirements, attached. Note that we prefer plans folded to fit into the file system, 9" x 14" . Please respond within 2 business days to confirm and reserve the submittal meeting date. Thanks, Janet Russell Express Coordinator I of] 6/26/2008 6:20 PM RE: Express Info Subject: RE: Express Info From: "Ryan Hambleton" <rambleton c stewart-eng.com> Date: Thu, 26 Jun 2008 07:37:54 -0400 To: "Janet Russell" <Janet.Russel l@ncmai1.net> CC: "Joe Puckett" <jpuckett@stewart-eng.com> Janet, Please find attach our request for a scoping meeting on the MCAS New River Maintenance Hangar, located in Jacksonville, NC. Also attached is a stormwater narrative and site plan for information prior to the scoping meeting. We would like to have the meeting sometime between July 8th and July loth with both DWQ and DLR personnel. If you need anything else please let me know. Thank you, Ryan Hambleton, PE Project Manager STEWART ENGINEERING 421 Fayetteville Street, Suite 400 Raleigh, NC 27601 Direct 919.866.4819 Fax 919.380.8752 Engineering. Innovation. Solutions.----- Original Message ----- From: Janet Russell[mailto:Janet.Russell@ncmail.neti Sent: Thursday, June 19, 2008 5:32 PM To: Ryan Hambleton Subject: Express Info Ryan: To get into the Express Program, please submit the Express Request, complete stormwater narrative, vicinity map, and pdf site plan (if available). This gets you scheduled. Also, indicate any dates/times that you are not available in the next couple of weeks. For Onslow County, a phase II county, the Session Law outlines the design criteria which is more strict that the non -Phase II counties. Start reading around page 13. It is attached. You can request a "scoping" meeting if you feel you need one or go straight for the submittal meeting. At a submittal meeting, we won't take an incomplete application package anyway and it could turn into a "scoping" meeting. Janet Russell Express Coordinator 910 796-7421 Express Request Content -Description: Application (Scoping Express Request Application (Scoping Meeting).doc Meeting).doc Content -Type: application/msword Content -Encoding: base64 Content -Description: Express Review App. Site Plan.pdf' Express Review App. Site Plan.pdf Content -Type: application/octet-stream Content -Encoding: base64 I of 2 6/26/2008 9:24 AM MCAS Neiv River Hangar Scope Meeting Subject: MCAS New River Flangar Scope Meeting From: "Ryan 1-lambleton" <rhambleton a Stewart-eng.com> Date: Thu, 26 Jun 2008 08:09:12 -0400 To: "Janet Russell" <Janet.Russel I@ncmai1.net> Janet, I just sent you a request for scope meeting on the New River Hangar project in Jacksonville. When setting up the meeting can you ensure that the meeting NOT be set up before 2pm on Wednesday, July 9th I forgot I have another commitment Wednesday morning. Ryan Hambleton, PE, LEED APd Project Manager STEWART ENGINEERING 421 Fayetteville Street, Suite 400 Raleigh, NC 27601 Direct 919.866.4819 Fax 919.380.8752 Engineering. Innovation. Solutions. I of] 6/26/2008 9:18 AM For DENR Use ONLY North Carolina Department of Environment and Reviewer:- Natural Resources Submit '1-$ NCDENR Request for Express Permit Review Time: l �o Confirm � NA�•r�•r}t FILL-IN all the information below and CHECK the Permit(s) you are requesting for express review. FAX or Email the completed form to Express Coordinator along with a completed DETAILED narrative, site plan (PDF file) and vicinity map (same items expected in the application package of the project location. Include this form in the application package. • Asheville Region -Alison Davidson 828-296.4698;alison.davidson(&.ncmaiLnet • Fayetteville or Raleigh Region -David Lee 919-791-4203; david.lee(@ncmail.net • Mooresville & -Patrick Grogan 704-663-3772 or patrick.grogan(( ncmail.net • Washington Region -Lyn Hardison 252-946-9215 or Ivn.hardison(dncmail.net • Wilmington Region -Janet Russell 910-350.2004 or ianet.russell(a)ncmail.net NOTE: Project application received after 12 noon will be stamped in the following work day. Project Name: MICAS NEW RIVER AIRCRAFT MAINTENANCE HANGAR County: ONSLOW Applicant: CARL BAKER Company: MCB CAMP LEJEUNE, DESIGN BRANCH PUBLIC WORKS DIVI Address: 1005 MICHAEL ROAD City: CAMP LEJEUNE, State: NC Zip: 28547 Phone:919-866-4819 Fax:919-380-8752 Email: RHambleton(o)Stewart-enq.com n E C E I V E Project is Drains into SC waters Project Located in NEW RIVER River Basin Engineer/Consultant: RYAN HAMBLETON Company: STEWART ENGINEERING, INC JUN 2 6 20G8 [u ;u{ r L Address: 21 FAYETTEVILLE ST. SUITE 400. City: RALEIGH, State: INC Zip: 27603 Phone: 910-451-2213 Fax::910-451-2927 Email: Cad.h.Baker(a)usmc.mil DWQ (Check all that apply) RROJ k ------ IN Scoping Meeting ONLY ® DWQ, ❑ DCM, ® DLR, ❑ OTHER: ❑ Stream Origin Determination: # of stream calls — Please attach TOPO map marking the areas in questions ® 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 2 # Treatment Systems ❑ High Density —Constructive Wetlands _ # Treatment Systems ❑ High Density -Other _ # Treatment Systems ElMODIFICATION SW _ (Provide permit #) ❑ Coastal Management ❑ Excavation & Fill ❑ Bridges & Culverts ❑ Structures Information ❑ Upland Development ❑ Marina Development ❑ Urban Waterfront ka® Land Quality ® Erosion and Sedimentation Control Plan with acres to be disturbed.(CK #_ (for DENR use)) S /WETLANDS QUESTIONS MUST BE ADDRESSED BELOW eeC f-\'MrA V �� ❑ Wetlands (401): Check all that apply Wetlands on Site ❑ Yes ® No Wetlands Delineation has been completed: ❑ Yes ❑ No US ACOE Approval of Delineation completed: ❑ Yes ❑ No 404 Application in Process w/ US ACOE: ❑ Yes ❑ No Permit Received from US ACOE ❑ Yes ❑ No Fee Split for multiple permits: (Check # Isolated wetland on Property ❑ Yes ❑ No Buffer Impacts: ❑ No ❑ YES: acre(s) Minor Variance: ❑ No ❑ YES Major General Variance ❑ No ❑ YES 401 Application required: ❑Yes ❑ No If YES, ❑ Regular Perennial, Blue line stream, etc on site ❑ yes ❑ No For DENR use only Total Fee Amount $ SUBMITTAL DATES Fee I SUBMITTAL DATES Fee CAMA $ Variance ❑ Ma'; ❑Min $ SW ❑ HD, ❑ LD, ❑ Gen $ 401: $ LQS $ Stream Deter,_ $ NOTES 1 i. xo wrx v a..ENEE uxn . 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I s e — m 1� It pry r I II mU z F 5 KEY PLAN ® STEWART g _^ —¢ GRAPHIC SCALE P- v e:_ �cs;o, n it Im o�$ U M I p 3 —q- 5 ------ DW Q PROJ # �� D C B A I& STEWART Storm Water Narrative MCAS NEW RIVER MAINTANANCE HANGAR P-526 Camp Lejeune, North Carolina June 25, 2008 General Information This Stormwater Narrative has been prepared specifically to address the requirements for the Express Review for general permit. The project site does not drain to Outstanding Resource Waters nor is it within one-half mile of SA waters or unnamed tributaries of SA water. The project is located within Onslow county and therefore, stormwater management must be in accordance with NPDF.SPhase //Post Construction rules and Senate Law 1566. Site Information The MCAS New River Maintenance Hangar site is located on Marine Corp Air Station (MCAS) New River off of Curtis road just east of existing aircraft hangar 504 (see vicinity Map). The site lies within the New River basin and is just outside 1/2 miles from the coastal waters of the New River, which per mapping provided by the Navy for Camp Lejeune and MCAS New River are considered SC waters. The following information is providedL ffory ExExpress Review; 1n. n, a (/kFor0 l_JM V �✓�iR r Na ' � e + 1 Marfns � corps C3 'Atr Sta PRC A17 No � nh Rnn —J It RIVER HANGAR D U 1UN 2 6 2009 PROJ # DW O a. Acres Being Disturbed - 8.46 acrs b. Acres in Wetlands - None f. Ownership Information - g. Description of Development Proposal - See below; h. Tax parcel ID Number The project site is not located within the 100-yr flood elevation as defined by FIRM 37204364003 nor are there any wetlands identified within the site The site is comprised of existing impervious (airfield concrete apron) and an undeveloped open field to the north of the apron. Both area's of the site currently drain to an existing ditch and culvert system which outfalls offsite to wetlands and thence the New River to the east and south of the site. The overall drainage patterns will remain the same in the proposed condition. Proposed Improvements The project area consists of the existing apron which the proposed new maintenance hangar will be located. This existing concrete slab and base will be completely removed under the structure only. The remaining existing concrete slab proposed to be demolished will have the individual slab units removed (leaving the base stone in place) as necessary to promote positive drainage away from the proposed hangar. A 200+ car parking lot and sidewalk is proposed north of the proposed hangar within the existing open field. �E C E 1 V E n JUN 2 6 2oc8 PROJ N _ DWO