3 12/07/2015 FINAL SUBMISSION 2 11/02/ SUBMISSION #3 1 08/31/ SUBMISSION #2 NO. DATE DESCRIPTION COUNTY REVISIONS SUBMITTED

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13 3 12/07/2015 FINAL SUBMISSION 2 11/02/ SUBMISSION #3 1 08/31/ SUBMISSION #2 NO. DATE DESCRIPTION COUNTY REVISIONS SUBMITTED DATE: DESIGNED: LTS PROJECT/FILE NO. JULY 6, 2015 CHECKED: EJI VV7748A VIKA REVISIONS VER ARLINGTON COUNTY, VIRGINIA DEPARTMENT OF ENVIRONMENTAL SERVICES STORMWATER MANAGEMENT PLAN AND NARRATIVE COLUMBIA PIKE VILLAGE CENTER SUBMISSION SCALE: 1" = 25' ARLINGTON COUNTY, VIRGINIA SHEET: C-13 NORTH (VCS 83) LEGEND MIN. 63,000 SF ROOF AREA TO JELLYFISH FILTERS (OR APPROVED EQUAL WITH MIN 50% PHOSPHOROUS REMOVAL EFFICIENCY) SITE STORMWATER MANAGEMENT NARRATIVE ON THE EXISTING 2.99 ACRE SITE THERE EXISTS A 1-STORY BRICK BUILDING, ASSOCIATED PARKING LOT, CONCRETE PATIO, AND LANDSCAPED AREA. THE EXISTING SITE IS APPROXIMATELY 88.62% IMPERVIOUS WITH NO EVIDENCE OF EXISTING STORMWATER MANAGEMENT (SWM) FACILITIES ON SITE FROM RECORD AND VISUAL INSPECTION. THE PROPOSED SWM BOUNDARY (2.99 AC) ENCOMPASSES THE SITE AREA. THE PROPOSED REDEVELOPMENT CONSISTS OF A 6-STORY MIXED USE RETAIL AND RESIDENTIAL BUILDING. THE PROPOSED SITE WILL BE APPROXIMATELY 95.98% IMPERVIOUS AND WILL PROVIDE SWM MEASURES IN ACCORDANCE WITH THE NEW 2014 VIRGINIA STATE REGULATIONS FOR REDEVELOPMENT. AS SHOWN ON SHEET C-14 THE REQUIRED PHOSPHORUS REMOVAL RATE OF 1.54 POUNDS PER YEAR WILL BE PROVIDED BY THE SWM PRACTICES INTEGRATED INTO THIS DEVELOPMENT. SITE LIMITATIONS, SUCH AS TOPOGRAPHY, AND DCR SETBACK RESTRICTIONS PRECLUDE THE USE OF TRADITIONAL BIO-RETENTION FACILITIES ON THIS SITE. AS SUCH, TREATMENT HAS BEEN PROVIDED BY STRUCTURAL BMP FACILITIES. IT SHOULD BE NOTED IN THE REDEVELOPMENT COMPUTATIONS FOR THE PROPOSED SITE THAT THE IMPERVIOUS AREA INCLUDES THE FOLLOWING: BUILDING ROOF AREA, PAVEMENT AND SIDEWALK, AND THE AREA OF THE UNDERGROUND GARAGE. MANUFACTURED BMP FACILITIES ARE PROPOSED (JELLYFISH FILTERS OR AN APPROVED EQUAL WITH A MINIMUM PHOSPHOROUS REMOVAL EFFICIENCY OF 50%) TO TREAT A MINIMUM OF 63,000 SF OR ROOF AREA TO MEET ARLINGTON COUNTY WATER QUALITY REQUIREMENTS (SEE SHEET C-14 FOR COMPUTATIONS). THE PROPOSED SITE IMPERVIOUSNESS IS GREATER THAN THE EXISTING IMPERVIOUSNESS. IN ORDER TO MEET THE ARLINGTON COUNTY DETENTION REQUIREMENTS, A MINIMUM 6,000 CF SWM VAULT HAS BEEN PROPOSED (SEE SHEET C-14 FOR COMPUTATIONS). THE FINAL DIMENSIONS AND LOCATION OF THIS SWM VAULT WILL BE DETERMINED AT THE TIME OF FINAL ENGINEERED SITE PLAN. RUNOFF WILL BE CONVEYED FROM THE SWM FACILITIES INTO THE EXISTING STORM DRAIN SYSTEM (IN COLUMBIA PIKE) VIA A SERIES OF PROPOSED STORM PIPES. FINAL STORM PIPE LAYOUT AND STORM WATER MANAGEMENT STRATEGY WILL BE DETERMINED AT TIME OF FESP, IN COORDINATION WITH ARLINGTON COUNTY STAFF. FILE: P:\projects\7748\7748A\CADD - P\PLANNING\PLANNING DRAWINGS\7748A SWM.dwg USER: kantonucci DATE: December 2, 2015 TIME: 10:02:56 AM

14 VIRGINIA RUNOFF REDUCTION SITE SUMMARY VIRGINIA RUNOFF REDUCTION RESULTS BMP NOTE: THE DEVELOPMENT PROPOSED ON THE SUBJECT SITE WILL PROVIDE A PHOSPHOROUS REMOVAL RATE AS REQUIRED BY DEQ, AT A MINIMUM. THE DEVELOPER RESERVES THE RIGHT TO UTILIZE LID TECHNIQUES (PER THE DESIGN SPECIFICATION OF THE VIRGINIA STORMWATER BMP CLEARINGHOUSE AND AS AMENDED/MODIFIED BY ARLINGTON DES) OR THE USE OF MANUFACTURED BMPS IN ACCORDANCE WITH THE BMP CLEARINGHOUSE, OR A COMBINATION THEREOF. FINAL DESIGN, LOCATION AND TYPES OF BMP SYSTEM(S) SHALL BE ESTABLISHED WITH FINAL CONSTRUCTION PLANS AND MAY BE REVISED TO ALTERNATES ALLOWED BY DES. 3 12/07/2015 FINAL SUBMISSION 2 11/02/ SUBMISSION #3 1 08/31/ SUBMISSION #2 NO. DATE DESCRIPTION COUNTY REVISIONS SUBMITTED DATE: DESIGNED: LTS PROJECT/FILE NO. JULY 6, 2015 CHECKED: EJI VV7748A VIKA REVISIONS VER ARLINGTON COUNTY, VIRGINIA DEPARTMENT OF ENVIRONMENTAL SERVICES BMP COMPUTATIONS COLUMBIA PIKE VILLAGE CENTER SUBMISSION SCALE: N/A ARLINGTON COUNTY, VIRGINIA SHEET: C-14 VIRGINIA RUNOFF REDUCTION CREDIT SUMMARY ARLINGTON DETENTION REQUIREMENTS FILE: P:\projects\7748\7748A\CADD - P\PLANNING\PLANNING DRAWINGS\7748A SWM.dwg USER: kantonucci DATE: December 2, 2015 TIME: 10:02:56 AM

15 CONCEPTUAL MANUFACTURED BMP (JELLYFISH) DETAIL NOT TO SCALE NOTE: APPROXIMATE NUMBER OF HI-FLO CARTRIDGES FOR JELLYFISH #1 = 6 APPROXIMATE NUMBER OF HI-FLO CARTRIDGES FOR JELLYFISH #2 = 6 APPROXIMATE NUMBER OF DRAWDOWN CARTRIDGES FOR JELLYFISH #1 = 1 APPROXIMATE NUMBER OF DRAWDOWN CARTRIDGES FOR JELLYFISH #2 = 1 MANUFACTURED BMP SPECIFICATIONS ARE APPROXIMATE BASED ON THE APPROXIMATE AREA DRAINING TO EACH FACILITY. FINAL SPECIFICATIONS WILL BE PROVIDED AT TIME OF FINAL ENGINEERED SITE PLAN. 3 12/07/2015 FINAL SUBMISSION 2 11/02/ SUBMISSION #3 1 08/31/ SUBMISSION #2 NO. DATE SUBMITTED DATE: JULY 6, 2015 DESCRIPTION COUNTY REVISIONS DESIGNED: LTS CHECKED: EJI PROJECT/FILE NO. VV7748A VER ARLINGTON COUNTY, VIRGINIA DEPARTMENT OF ENVIRONMENTAL SERVICES VIKA REVISIONS SWM DETAILS COLUMBIA PIKE VILLAGE CENTER SUBMISSION SCALE: N/A ARLINGTON COUNTY, VIRGINIA SHEET: C-15 FILE: P:\projects\7748\7748A\CADD - P\PLANNING\PLANNING DRAWINGS\7748A SWM.dwg USER: kantonucci DATE: December 2, 2015 TIME: 10:02:56 AM

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