FocalPoint****************

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1 FocalPoint HighPerformanceModular BiofiltrationSystem(HPMBS) Introduction

2 IntroductiontoFocalPointHPMBS The FocalPoint is an ultra2efficient, modular and scalable biofiltration system that treats and drains large volumes of stormwater runoff in a small footprint to meet post construction Green Infrastructure (GI) Low Impact Development (LID) or TraditionalPCSMstormwatertreatmentrequirements.Thesystemcanbeinstalled alongtheedgeofaroadwaybehindcurbline,inlandscapedstormwaterbasinsand beincorporatedintoanurbangreeninfrastructurestreetscape.someexamplesof thesystemareillustratedbelow: ThemodularFocalPointHPMBSisacomplete,integratedsystemwithademanding specification that insures functionality, performance and maintainability. With rigorous quality assurance standards and post2construction in2situ performance verification,focalpointhpmbsprovidesguaranteedperformance. The FocalPoint System is designed and sold on a sq. ft. basis.thesystemprofile(right)is provided as a complete package. With it s soft2shell and scalability design it brings new flexibility to stormwatertreatmentdesign.the FocalPoint System profile can be incorporated as an alternative to traditional low flow bioretention mixes into bump2outs, tree trenchesorboxes,raingardensor other areas where higher efficiency are desired or demanded. FocalPointHPMBSComponents Asshown,thesystem(Fromthetopdown)consistsof: Plantings HardwoodShredded Mulch HighPerformance BiofiltrationMedia(18 ) CleanBridgingStone(6 ) OpenMesh SeparationMicrogrid ModularUnderdrain 9 Typ. Expandableasstorageneeds mandate. Plants: Placed in the media that provide sustainability of the system by providing both long2term aeration and drainage through the media as well as uptake of the pollutantsthemediahaspreviouslyremovedfromtherunofftreatedinthemedia. 2

3 The plants represent the only component that is not supplied by ACF Environmental.Arecommendedplantlistisavailableuponrequest. Plants:Provide pollutantuptake andmedia sustainability. Mulch:Pre2treatment mechanismandprimary maintenance component. Mulch:Threeinchofcleanshreddedhardwoodmulchisplacedontopofthemedia to serve as a pretreatment and thermal2barrier layer. The replacement of the 3 mulchlayerat6to12monthintervalsrepresentsthemaincomponentoflong2term systemmaintenance.maintenanceisdiscussedonpage9. High Flow Media: The high flow media infiltrates/processes/conveysata rate of 100inchesperhour.Assuch,thesizeandvolumeoftheengineeredmediabedscan be reduced by 80% or more, when compared to typical bioretention systems that infiltrateatratesoflessthanfive(5)inchesperhour.reducingsystemsizebrings multiple benefits, including reduced and simplified maintenance procedures, savingsintheamountofexcavation(greatbenefitwhenworkingwithcontaminated soilsandshallowbedrock),reductioninquantityofimpermeableliner(ifrequired), stone, underdrain, materials to name a few. FocalPoint assures performance by providing media testing reports prior to shipment and performing an in2situ test afterinstallationtoconfirmtheinfiltrationrate. HighPerformanceMedia:HighFlowRate (100in2hr/200ftday)andPollutantRemovalEfficiency TSS=91% Nitrogen=48% Phosphorous= 66% 3

4 Separation Layer: Below the high flow media is a 62inch bridging stone layer (washed/clean stone) and then an open mesh Micro2Grid. This is an open grid mesh, not a restrictive non2woven fabric(which is commonly a primary source of premature failure of bioretention and biofiltration systems). The purpose of the opengridistopreventthe62inchbridgingstonelayerfromenteringthefocalpoint modular underdrain. All of the FocalPoint components are shipped as a bundled packagetoprovidequalitycontrolandqualityassuranceoftheentiresystem. Modular Underdrain ROTank System: The FocalPoint underdrain system typicallyconsistsofa9.5inchtallboxunderdrain(r2tank),butcanbeexpanded bothverticallyandhorizontallytoachieveinfiltrationanddetentiongoals.thebox underdrain is more efficient at collecting and conveying the runoff than a typical crushedstoneandpipeconfiguration,andcanbeaccessedviathesysteminspection port. This is important when considering the rate at which the runoff is passing throughthemedia(discussedabove). 6 SeparationLayer Micro2 Mesh Clean Stone NoGeotextile=NoClogging QA/QC:Allcomponents bundledforqualitycontrol Media HighPerformance(ROTank)Underdrain 9.5 Mini Moduleis Typical. TheFocalPointUnderdrain/R2Tank Systemcanbeexpandedoutfor additionalstorageneeds. Moredetailedinfobeginsonpage19 2 Panelisalsoan Option. The2 Panelcan overcomehighgroundwater, utilityandotherobstructionor shallowapplicationissues. Mulch Stone 4

5 TheoptiontoexpandtheR2Tankmodularunder2drainallows for unprecedented versatility; FocalPoint can provide full treatmentforin2line treatandrelease ordetentiondesigns orpre2treatmentforinfiltration,harvestingandcombination applications. In2Line (Treat&Release) Infiltration Detention Harvest Combination RunoffVolume(cf) Moredetailedinformationontheunder2drainapplicationsbeginsonpage19. SurfaceDepression/TemporaryStorage:TheFocalPointHPMBSutilizesberms orcurbstocreateashallowdepressionthatprovidestemporarystoragetomitigate theissuesassociatedwithpeakflowdischarges.astheflowincreasesduringthe runoff event this surface storage (typically to a depth of 628 inches) can be leveraged to provide maximum flexibility and efficiency in taking advantage of whateverstormwatermanagementfootprintisavailableforanygivensite. During the run2up to the peak flow phase of the storm the surface storage remains emptywhiletherunoffflowsthroughthefocalpointtreatmentfootprint(flowcapacity offocalpointfootprint>flowrateofrunoffintothesystem). RunoffVolume(cf) RunoffVolume(cf) Duringthepeakflowphaseofthestormthesurfacedepressionprovidestemporary storage for the peak volume (Flow capacity of FocalPoint footprint < flow rate of runoffintothesystem). Appropriate TR255 Hydrograph = Water Quality Volume = FocalPoint Treatment = Volume > WQv (to bypass) Appropriate TR255 PeakWQvinTemporaryStorage Hydrograph During the run2up to the peak flow phase of the Appropriate TR255 Hydrograph After the peak flow phase of the storm event the volume in the temporary storage begins to draw down as the FocalPoint continues to treat at a rate higher than the incoming runoff(flow capacity of FocalPoint footprint > flow rate of runoff into the system). 5

6 WhyFocalPointBioFiltration?BasicDesign&Implementation FocalPoint s high flow media allows for flexible and cost effective alternative approachestobothtraditionalbioretentionand manufactured treatment devices (MTDs) and does so based on a fundamental TR255 rainfall and distribution approach.thefocalpointsystemissizedtotreattheentire WaterQualityVolume (WQv). Below is a comparison of a standard bioretention approach and a FocalPoint biofiltration example (ACF Design Support provides calculation assistanceforallhydraulicdesignrequirements). TraditionalBioretentionDesign: FocalPoint Design can treat the same volume at 75% or less of the footprint. The 25% footprint reduction above is a minimum expectation when comparing FocalPointbiofiltrationdesigntotraditionalBioretentiondesign.Furtherreduction canbeachievedperfocalpointscalability(asdiscussedonthefollowingpage). FocalPointSystemScalability FocalPoint s fundamental TR255 rainfall and distribution approach to sizing provides exact computations as to where every cubic foot of runoff is at any time during the rainfall / runoff event. This approach eliminates the black box sizing approach promoted by most of the Manufactured Treatment Devices (MTDs) as state of the practice. The ability to leverage the size of the FocalPoint treatment footprint within the surface depression available for temporary storage allows for theuniquescalabilityofthesystem. Presented below are some example calculations and images of projects using this designapproachtomeetthewaterqualityvolume(wqv)regulatoryrequirements. All scalability examples are based on a Drainage Area (DA) of 0.20 acres with a CurveNumber(CN)of98anda24hourTypeIIdesignstormdistributionandtreat thesamewqv. ScalabilityDesignExamples The following parameters apply for the Drainage Area provided for the scalability examples for the WQv: DA = 0.20 Acres (8,712 sf), 24 hour Type II event = 1.70 inchesofrain(1.5 runoff)andatotalwaterqualityvolume(wqv)of1,073cf: 1,000SqFtofStandard BioretentionMix FlowRateof2 to5 perhr/4 to 10 perday = FocalPoint TemporarySurface DrainArea(DA) Footprint StorageFootprint 6 = Media Treatment Footprint Atleast 25% reduction intotal Footprint required FocalPointDesign: 750SqFtofGrassedor LandscapedArea SmallFocalPointFootprintofHigh FlowMedia2100 perhr/200ftper daywithinthe750sqftfootprint

7 7 Projectexamplesusingthissizingapproach. Blue=FocalPoint,Yellow=TempStorage Option#1:TotalArea=568SqFt(8 x71 ),FocalPointFootprint=35SqFt(5 x7 ). 7ft 5ft 568sqftTemporary PojndingArea 8ft 35sqftFP Footprint DrainageArea=0.20Acres Option#3:TotalArea=108SqFt(8 x13.5 ),FocalPointFootprint=108SqFt(8 x13.5 ). 71ft Option#2:TotalArea=280SqFt(5 x35 ),FocalPointFootprint=75SqFt(5 x15 ). 35ft 8ft 15ft 5ft 75sqft FP Footprint DrainageArea=0.20Acres DrainageArea=0.20Acres 108sqft FP Footprint 13.5ft 8ft Option#2:TotalArea=280SqFt(8 x35 ),FocalPointFootprint=75SqFt(5 x15 ) 15 ). 280sqft TempPonding Area The108sqftTotalAreaisthesame asthe108sqftfocalpointfootprint

8 Projectexamplesusingthissizingapproach.Blue=FocalPoint,Yellow=TempStorage. FocalPoint can easily be incorporated into current Treebox, Bump2out and Bio2 swale designstoovercomeinherentdeficienciesandlimitations.themodularnature of the FocalPoint system components makes it friendly to retrofit designs where existinginfrastructurecouldprohibitlargersingleunitalternatives. FocalPointMaintenance: MaintenanceoftheFocalPointSystemissimple.Annualremovalandreplacementof mulch is the main task at hand. This can be performed by public works/maintenance/landscape contractor as part of regular streetscape maintenanceorbylocalarborist/horticulturist.asitisanopensystem,itiseasyto access the entire surface. Any winter sand gets caught by the mulch and can be easily raked out with the mulch. The first year of maintenance is provided at no charge and ACF Environmental can provide training to the identified maintenance partyifneeded. 1.Pickuptrash Proper installation and maintenance methods are comprehensively presented in the FocalPoint Install and MaintenanceManuals. 2.ReplaceMulch 3.Removesedimentfromentryareas 8

9 IntroductiontotheFocalPointUnderdrain/ROTankSystem The R2Tank stormwater system provides 95%VoidSpaceforStorage modular underground storage of stormwater. The system is an alternative to stormwater basinsandamoreefficient(95%voidspacein module), space saving alternative to other underground systems for detention (SWM), infiltration (SWM/LID/GI), recycling stormwater (GI) or combination applications (asillustratedbelow). During a rain event fills the R2Tank, stormwater can flow into the drainage system, infiltrateintotheground,orbereused.thesystemisanalternativetostormwater basinsanda moreefficient,spacesavingalternativeto otherunderground systems fordetention,infiltration,andrecyclingstormwater. Whenusedforinfiltration,thelowprofileaspectoftheR2TankSystemcanprovide a large footprint of shallow infiltration to enhance the total infiltration rate separatelyfromthelimitsofspaceavailabilityatthesurface.thissameapproach can also solve problems dealing with high ground water levels, high bedrock elevationsorshallowutilityobstacles. Infiltration Detention ExtendedtoEnhance InfiltrationInterface Harvest Combination Modular Versatility Depth: R2Tank modules can be assembled to a variety of heights from2inchestojustunder7feet.thisrigidsystem canbe placedbeneatha varietyof surfaces including: Parking Lots, Streets and Access Roads, Driveways (H20 & HS25), Landscaping,AthleticFields/Playgrounds,SwalesandChannels. Liner 9

10 ROTankModulesMiniandSinglesConfigurations: Depth=9.45 to83.46 (in8o9inchincrements) Storage=2.30cfto20.34cf R2TankSingle (17.32 ) R2TankMini (9.45 ) R2TankXD2 Panels (92%Void)canbe utilizedfrom2 to10 Modular Versatility Layout Arrangement: The R2Tank module s3.08sqftfootprintcaneasilyadapttocomplexand irregularapplicationfootprints,asillustratedbelow. R2TankModulesshipasunassembledpanels,providingsignificantcostsavings.ACFprovides anassembledr2tankoptionsothatcontractorshavecostcertainty.onceassembled,allsizes ofmodulesareindividualunitsthatcanbeeasilyhandledandplaced. 10

11 1.Square Pegfor Square Hole R2Tankisa squarepegforasquarehole makingengineeringcomputationsand sizingsimple.acfr2tankisincludedinthe ChamberWizard withinhydrocad. 2.R2Tankprovidesstabilityforlateralandverticalpressures. 3.R2Tankeliminateslowvoidspaceandcompactionissuesassociatedwithpipeand chambersystems. H220Loads Geogrid =Min.20 cover 2 WideStone Perimeter R2Tank Modules (Encapsulated) 3 StoneBase 12 Stonecover Fillplaced and compacted in12 lifts ThetypicalsectionfortheR2Tank P HD (HeavyDuty)systemconsistsofacompacted subgrade (un2compacted for infiltration) and the minimum cover and fill as representedtotheright.r2tank HD canaccommodateamaximumof7feetofcover overthemodules.note:r2tank SD (superduty)isavailableforcoverupto10foot overmodules. Pipe connections to R2Tank are easily facilitated by using a prefabricated Pipe Boot ;horizontal,vertical,fabricorliner.anotheroptionistoconnectdirectlyto a catch basin/drain. Both options eliminate the cost and complexity of header systemsrequiredforpipeorarchchamberssystems. 11

12 TheR2Tank systemdoes notrequire costly and project specific manifolds, instead it only requires easy connections to convey the runoff in andoutofthesystem.thisbenefitis perfect when the intent is to implement a decentralized GI/LID application. The ability to eliminate costly conveyance infrastructure can haveasignificanteffectontheglobal costofyourpcsmapproach. R2Tank HD canenhancetraditionalswm byprovidingamoreefficient95%void space storage while eliminating the manifolds. In reference to maintenance, cleanout or flushing of the R2Tank system is facilitated by observation 2maintenance ports. Sometimesa Forebay approach canbeeffective. CentralizedEfficiency R2Tank HD System Option While pretreatment is not required in most states, it is imperative for the long term sustainabilityofallundergroundsystems,especiallyforinfiltrationsystems.toprotect ther2tanksystemfromtrash,debrisandsediment,permanystate srequirementsor recommendations,acfprovidesseveralpretreatmentoptionsupstreamofther2tank system, both mechanical and biological, as follows: Trash Guard Plus, Fabco Connector Pipe Screen, StormSack, StormBasin and StormSafe, FocalPoint BioFiltration. Traditional SWM using infrastructuretocollectandconvey run2offtocentralizedsystems. Centralized DecentralizedOn.Lot Progressive LID and GI approach: Managingrun2offatitssourcewith smallon2lotr2tank HD systems 12

13 13 ExampleROTankProjects: AutoLot EnhancedSWM ParkingLotHarvest LID/GI HarvestunderAthleticField LID/GI OpenBasinRetrofit EnhancedSWM DecentralizedResidential LID/GI LID/GI UrbanRetrofitUnderTreeboxes LID/GI ParkingLotHarvest LID/GI