WQ0000798_More Information Received_20211004

Initial Review
Reviewer Thornburg, Nathaniel D
Is this submittal an application? (Excluding additional information.)*
r Yes r No
If not an application what is the submittal type?*
Permit Number (IR)*
Applicant/Permittee
Email Notifications
Does this need review by the hydrogeologist?*
Regional Office
CO Reviewer
Admin Reviewer
Annual Report
Residual Annual Report
r Additional Information
r Other
WQ0000798
Brunswick County
r Yes s No

Submittal Form
Project Contact Information
Rease provide information on the person to be contacted by N B Staff regarding electronic receipt, another correspondence. ittal, confirmation of iptd othd
.......................................................... ronc su_ -
Name * Carter Hubard
Email Address*
[e-mail]
Project Information
........ .................................................................................................................................................. .
Application/Document Type* r New (Fee Req ui red)
r Modification - Major (Fee Required)
r Renewal with Major Modification (Fee
Required)
r Annual Report
c Additional Information
r Other
Phone Number*
19107624200
O Modification - Minor
C Renewal
C GW-59, NDMR, NDMLR, NDAR-1,
NDAR-2
r Residual Annual Report
r Change of Ownership
We no longer accept these monitoring reports through this portal. Please click on the link below and it will take you to the correct form.
https://edocs.deq.nc.gov/Forms/NonDischarge_Monitoring_Report
Permit Type:*
r Wastewater Irrigation
r High -Rate Infiltration
r Other Wastewater
r Reclaimed Water
r Closed -Loop Recycle
r Residuals
r Single -Family Residence Wastewater
r Other
Irrigation
Permit Number:*
W00000798
Has Current Existing pernit number
Applicant/Permittee Address*
PO Box249 Bolivia NC 28422
Facility Name *
Shallotte WWTF
Please provide comments/notes on your current submittal below.
Additional Information Request #2 (9/3/2021) response with supporting documentation
At this time, paper copies are no longer required. If you have any questions about what is required, please contact Nathaniel Thornburg
at [e-mail].
Please attach all information required or requested for this submittal to be reviewed here.*
(Application Form Engineering Rans, Specifications, Calculations, Bc.)
2021-10-04_Mulberry Comment Response.pdf 50.64MB
Upload only 1 FLFdocurrent (less than 250 W). tvLRiple documents rust be contained into one FDFfile unless file is larger than
upload limit.
* V By checking this box, I acknowledge that I understand the application will not be
accepted for pre -review until the fee (if required) has been received by the Non -
Discharge Branch. Application fees must be submitted by check or money order
and made payable to the North Carolina Department of Environmental Quality
(NCDEQ). I also confirm that the uploaded document is a single PDF with all parts
of the application in correct order (as specified by the application).
Mail payment to:
NCDEQ — Division of Water Resources
Attn: Non -Discharge Branch
1617 Mail Service Center
Raleigh, NC 27699-1617
Signature
Submission Date 10/4/2021

October4,2021
SubmittedviaelectroniccopytoDEQuploadsite
LaurenRaupPlummer,PE,EngineerIII
DivisionofWaterResources
NorthCarolinaDepartmentofEnvironmentalQuality
512NorthSalisburyStreet
Raleigh,NorthCarolina276991617
Subject:AdditionalInformationRequest#2
ApplicationNo.WQ0000798
ShallotteWWTF
BrunswickCountyWastewaterIrrigationSystem
DearMs.Plummer:
InresponsetotheAdditionalInformationRequest#2,datedSeptember3,2021,toBrunswickCounty,
requestingadditionalinformationfortheabovementionedproject,weareprovidingresponsesand
reviseddocuments.Thecommentswithresponsesinblueitalicsareprovidedonthefollowing
pages.Supplementalandreviseddocumentsaresubmittedhereinasfollows:
FindingofNoSignificantImpact
WetlandPermits
RevisedandsignedWWISApplication
UpdatedSoilsTesting,AgronomistEvaluationandHydrogeologicReportSections
EngineeringPlans
HydraulicProfileSheetG5
LagoonPipingPlanC16
ForceMainBypassandCheckValveDetailSheetC21.1
InfluentForceMainSheetsC22toC26
EffluentForceMainSheetsC33toC38
SprayFieldForceMainSheetsC40toC47
HighRateInfiltrationBasinPlanInsertsC53
SprayFieldLayoutSheetsC56andC57
LagoonOutletStructureSheetM31
HeadworksSheetM2
UtilityDetailsSheetD7
RevisedBidForm
300N.ThirdStreet,Suite301
Wilmington,NC28401
Tel.[phone]
www.wkdickson.comAviationWaterResourcesCommunityDevelopmentEnergy

Ms.RaupPlummer
October4,2021
Page2
SpecificationsCover,Sections099000Painting,Clearing311000,Seeding329214,andWaterUtility
DistributionPiping331100
OperationandMaintenancePlan
ResidualsPlan
PermitFigure
SealedCalculations
FigureofEndangeredSpeciesFigure7.10
A.CoverLetter:
1.Comment:Thesubmitteddocumentswereoverallorganizedtoamorenavigableformat;
however,thereseemstohavebeensomeconfusionaboutseparatingtheMulberryBranch
documentationfromShallotte.Thisconfusionhasledtosomeadditionalquestionsinthe
followingsections.Forexample,theforcemainsaffiliatedwiththeMulberryBranchplant
wereoftendifficulttoparseoutfromtheforcemainsaffiliatedwiththeShallotteplant
becausetheplanswerenotseparatedintoindividualfilesforthetwopermitapplications.
Whenrevisingthedocumentstoaddressthefollowingcomments,pleasealsotakecareto
makeclearindicationsofwhererevisionshaveoccurred.
Response:Commentnoted.Indicationofrevisionsareindicatedonplansheets.
2.Comment:Withinthecoverletterandunitprocesssummary,theeffluentpumpstation
consistingoftwo(2)820GPMat128ftTDHpumpsisnottobemodified.Pleaseaddress
thefollowing:
a.Comment:Isthisconfigurationcurrentlyoperatingasonemainpumpandonebackup
pump,asrequiredby15ANCAC02T.0305(h)?
Response:Yes,thispumpstationconsistsofonemainpumpandonebackuppump,asrequired
by15ANCAC02T0.305(h).The820GPMat128ftTDHisthepublisheddutypointforthese
pumps.Atthenewsprayfield,theflowratewillbeapproximately700GPMaspresentedinthe
DesignCalculationPackage.
b.Comment:Itisourunderstandingthatwiththeproposedfacilitypipingchanges,that
thesepumpswillbeusedtoirrigateallofthefieldsratherthanjustthefieldsoriginally
associatedwiththe325,000gpdplantupondecommissioningofthesmallerpumpstation.
Noinformationwasprovidedtodemonstratethesuitabilityoftheturbinepumpsforthe
additionalspayfields.Hasmodelingbeenperformedtoconfirmthatthepressureneeds
ofthesystemwillbemetwiththecurrenteffluentpumpstationconfiguration?

Ms.RaupPlummer
October4,2021
Page3
Response:Yes.Thereissufficientheadavailabletomeetthepressurerequirements.Eachspray
fieldisirrigatedataandnotallatonce.Thecalculationsforthesprayfieldandpressure
arepresentwithinthesubmittedDesignCalculationspackage.
B.ApplicationFee:
1.Nocomment.
C.Application:
1.Comment:WithinItemIV.3,theapplicantindicatedthatanEnvironmentalAssessment(EA)
wasrequiredunder15ANCAC01C;however,theEAwasstillunderreviewatthetimeof
thesubmittal.HasaFindingofNoSignificantImpactorRecordofDecisionbeenissuedto
theapplicantsincethelastsubmission?PleaseprovideanupdateonthestatusoftheEA.
Response:TheFindingofNoSignificantImpacthasbeenissued.Seeattached.
2.Comment:Portionsoftheproposedworkappeartooccurwithindesignatedwetlandsareas
pertheplansheets(e.g.thecrossingofMulberryBranchdepictedonPlanSheetC44).Have
Nationwide12/Section404orWetlands401permitsbeensubmittedand/orapproved?Please
updatetheTableinItemIV.4andprovideadditionalinformation,asneeded.
Response:ArmyCorpsofEngineersandNorthCarolinaDepartmentofWaterResourcespermits
havebeenreceived.Seeattached.
3.Comment:WithinItemIV.7,theapplicantindicatedthataflowreductionhasbeenapproved
under15ANCAC02T.0114(f).Furtherinformationregardingtheapprovedflowreduction
wasnotprovided.Pleaseprovideadditionalinformation.
Response:Existingpermittedflowwillnotbemodifiedinthisproject.Theapplicationhasbeen
revised.
4.Comment:ThemechanicalbarscreenlistedinItemV.11.a.indicatesadesignvolumeof3.125
gpd,shouldtheunitsbe3.125MGD?Also,pertheengineeringcalculationsitappearsthat
themanualbarscreenisdesignedforapeakflowof12.5MGD.Pleaseconfirmthatthe
mechanicalbarscreenissizedfor3.125MGDandrevisetheapplicationasnecessary.

Ms.RaupPlummer
October4,2021
Page4
Response:Themechanicalscreenisdesignedfor3.125MGD.Themanualscreencapacityhasbeen
updatedto3.125MGDaswell.
5.Comment:ItemV.11.elistsasingleequalizationbasinjetmotivepumpforsolidshandling.
ThispumpappearstobeidentifiedintheengineeringplansonSheetM8asEQP
andisalsoidentifiedassingularintheSpecifications(2213297).Pursuantto15ANCAC
02T.0505multiplepumpsshallbeprovidedwhereverpumpsareused.Pleasereviewand
reviseasneeded.
Response:Thispumpisexclusivelyformixinganddoesnotprovideanyformofconveyance.This
pumpispartofajetaerationsystem.Intheeventofpumpfailure,theblowerswouldcontinuetorun
andprovidepartialmixing.AsparepumpwillbekeptbyBrunswickCounty.
6.Comment:Withinthesetbacktable(ItemVIII.3),itisindicatedthatthereisa0footsetback
withtheirrigationsystemandsurfacewaters(streamsintermittentandperennial,perennial
waterbodies,andwetlands).Pursuantto15ANCAC02T.0506,thesetbacksforspray
irrigationsitesandsurfacewatersaretobemaintainedat100feet.TheNonDischargeBranch
doesnotwaivethissetback.
Response:Theentryonthepermithasbeenrevisedtoreflectthedesignedsetbackof100feetthatis
indicatedontheplans.
7.Comment:Page13oftheapplicationform(WWIS0616)wasnotsignedbyeitherthe
ProfessionalEngineerortheSignatureAuthority.Pursuantto15ANCAC02T.0106,permit
applicationsmustbesignedandcertifiedbyanappropriatesignatureauthority.Submittal
packagesincludingengineeringdocumentsmustbesigned,sealed,anddatedbyaNorth
Carlinalicensedprofessionalengineeringoodstanding.
Response:TheapplicationhasbeensignedbytheProfessionalEngineerandSignatureAuthority.
D.PropertyOwnershipDocumentation:
1.Nocomment.
E.SoilEvaluation:
1.Comment:Theprovideddocumentationwasextensive,anditappearedthatdatawas
includedfrompreviousprojectworkunrelatedtothisprojectwhichcreatedsomeconfusion.
Additionally,someofthepriorprojectreportsappearedtopresentconflictinginformation.

Ms.RaupPlummer
October4,2021
Page5
Pleaseprovidethefollowing,orprovideawrittenresponsetoeachitemandclearlypointus
towherethisinformationislocatedintheexistingapplication.
Response:ThereweretwoareasevaluatedforirrigationintheSoilsandHydrogeologicReport.
Thiscurrentsubmittaladdressesirrigationon11.18acresNorthofMulberryCreek.Basically,the
PiezometersP1P10definethis11.18acretract,GeotechboringW10andW11aretheonlyGeotech
boringsapplicabletothis11.18acreirrigationarea.Oneaquifertestwascompletedonthissiteas
wellAquiferTestNo.4,EarlyTimeDatadefinesthehydraulicconductivityandtransmissivity
underlyingtheproposedsprayirrigationarea.Additionaldocumentationisattached.
a.Comment:Awrittenresponsethatclearlyindicateshowmanyhydraulicconductivity
measurementsweretakenforeachsoilseriespresent,
Response:MostofthehydraulicconductivitymeasurementswereforasitesouthofMulberry
Creek.Therefore,newKsatanalysesfocusonthe11.18acretractproposedNorthofMulberry
Creek.Additionaldocumentationisattached.
b.Comment:AmapthatclearlyshowswhereallKsatmeasurementswereconducted
withintheproposedirrigationareaandtheirrelationtothesoilsmappedinthisarea,
Response:Additionaldocumentationisattached.
c.Comment:Acompletesoilprofiledescriptionforeachhydraulicconductivity
measurementpoint,
Response:Additionaldocumentationisattached.
d.Comment:Acopyofthefieldmeasurementsindicatingthatsteadystatewasreachedfor
eachtestconductedwithintherestrictivehorizonforeachsoilseriesand,
Response:TheKsatanalysesweremarginallyaccurateduetotheextremelyhighhydraulic
conductivity.Bothchambersdrainedcompletelypriortoestablishingsteadystate(flowrate
remainingconstantforthreeconsecutivereadings).Afterdrainingonetime,thechamberswere
quicklyrefilledinanefforttodetermineareasonableKsat.Theearlytimeaquifertestresults
indicatedahydraulicconductivitygreaterthan30feetperday.Thesandmatrixforthesoilsand
underlyingaquiferweresimilar.
Becauseofthedifficultyobtainingprecision,averyconservativeKsatof0.3in/hrwasusedinthe
waterbalance.

Ms.RaupPlummer
October4,2021
Page6
e.Comment:Asummarytableofthemeasurementsforeachsoilseriespresentinthe
proposedirrigationarea.
Response:Additionaldocumentationisattached.
F.AgronomistEvaluation:
1.Comment:TheSoilsReportindicatedthatphosphorusisslightlylimiting.Itwasunclearfrom
theengineeringdocumentswhichcrophasbeenselected,buthasphosphorusaccumulation
beenconsideredintheselectionofthefinalcovercropinField14?Pleaseprovideadditional
informationregardingproposednutrientmanagement.
Response:Therewasanerrorinthewordinginthetext.ThesiteisnotPhosphorouslimiting.
G.HydrogeologicReport:
1.Comment:TheSoilsandHydrogeologicReportsweresubmittedasacombineddocument,
pleaseseeSectionEforquestionspertainingtothehydrogeologicreport.
H.WaterBalance:
1.Nocomment.
I.EngineeringPlans:
1.Comment:Theproposedequalization(EQ)tankdoesnotappeartobedepictedorreferenced
alongthehydraulicprofileonSheetG5.PleasereviseSheetG5toincludetheEQtank.
Response:ThishasbeenaddedtothehydraulicprofileonSheetG5.
2.Comment:PerSheetC16,theproposedpipingconfigurationforExistingUpperLagoon1
depictsadrainlinetoExistingLowerLagoon3adjacenttotheinletline.Whilethenoteson
theapplicationindicatethatthislinewillbeusedformaintenancepurposesforExisting
UpperLagoon2(seeWWIS0616ItemV.3),itsproximitytotheinletlineposesasignificant
riskofshortcircuitingduringthesemaintenanceactivities.Pleasereviewandrevisethe
designaccordinglyandincludeadetailfortheproposedinletandoutletstructures.

Ms.RaupPlummer
October4,2021
Page7
Response:SheetC16hasbeenupdatedtorouteflowintooneupperlagoon,pipeaddedforflowto
secondupperlagoon,outletstructureandpipingtolowerlagoontooperateinserieswithnoShort
Circuitpotential.
3.Comment:Inadditiontoconcernswithshortcircuiting,itisunclearhowthefacilitywill
operateifLagoon1orLagoon3mustbetakenoutofserviceformaintenance.Forinstance,
howwillflowgetfromtheinfluentpumpstationtoLagoon2ifLagoon1mustbetakenoffline
forsolidsremoval?Pleaseprovideadditionalinformationandclarificationintheeventany
ofthelagoonsareneededtobetemporarilytakenoutofserviceformaintenanceorother
activities.
Response:TheproposedheadworksoftheShallotte/MulberryBranchWWTPcandivertflowtothe
MulberryBranchWWTPtotaketheShallotteWWTPoutofserviceifneeded.Currently,theShallotte
WWTPisdredgedperiodically,wheninservice,asnecessarytoremovesettledsolids.Theproposed
headworksandothermodificationswillallowthistooccurwiththeShallotteWWTPonlineoroffline
dependingonoperatorpreference.
4.Comment:TheplansetdepictsinfluentforcemainfromOceanHighwayWesttothe
proposedheadworks,hasthisbeenpermittedseparately?SheetsC22C25werenotprovided,
butarelatedpermitwasnotlistedintheapplicationtoindicatewhetherthisforcemainhad
previouslybeenreviewedandpermittedbyDEQstaff.Pleaseprovideadditionalinformation
andrevisetheengineeringdocumentsasnecessary.
Response:Theconnectiontotheregionaltransmissionmainwithinfluent16inchforcemaintothe
headworksisplannedtobepermittedintheWQ0000798permitmodification.Plansheetsare
submittedherein.
5.Comment:MultiplecalloutsonSheetC26indicatethattheheadworkspipingplanis
depictedonSheetC16.SheetC16istitledthePipingandincludesacallout
indicatingproposedheadworksseeSheetC14istheSiteLayout,
Grading&Drainageandpredominantlydepictsthecontrolpointsfortheproposed
structures.SheetC15wasnotprovidedbutislistedinthetableofcontentsasthe
PipingandnotthePipinganditisunclearifitisreferencingthe
MulberryBranchtreatmentfacilityorthesharedproposedheadworks.Pleasereviewand
revisethecalloutspertainingtotheheadworksandprovidethePiping
forourreview.
Response:SheetC15 referencestheMulberryBranchPiping.

Ms.RaupPlummer
October4,2021
Page8
6.Comment:TheLineSharedLineShareddetaildepicted
withinthePlanSetindicatesan18inchhorizontalseparationbetweenparallelpipesforthe
reclaimedwater(MulberryBranch)infiltrationbasinforcemainandthewastewatereffluent
(Shallotte)sprayfieldforcemain.Pursuantto15ANCAC02T.0305,theseparationbetween
reclaimedwaterlinesandsewerlinesmustbe18inchesintheverticalwithreclaimedover
sewer,or24inchesinthehorizontal.Pleasereviewandrevisethedetailandforcemain
alignmentsasnecessary.
Response:Spacinghasbeenincreasedto24inches.Thesesheetsarenotattachedbecausethesame
detailisshownoneverysheetoftheforcemain.
7.Comment:PerSheetC33,acalloutindicatingthelocationofanendangeredplantspeciesis
listednearSta.2+00thatreferstowithasimilarcalloutnearSta.9+00thatrefersto
however,theindicatednotesdonotappearapplicableorarenotprovidedonthe
plansheet.Thiserrorappearstooccurwithouttheplanset(i.e.SheetC41).Pleasereview
andreviseasneeded.
Response:Anotehasbeenaddedtotheplansheets.
8.Comment:PerSheetC40,theminimumcovernearSta.8+65alongtheSprayFieldForceMain
appearstobelessthan36incheswithaproposedpipematerialof12inchPVCatthatlocation.
Pursuantto15ANCAC02T.0305(g),forlessthan36inchesfromfinalearthgrade,ductile
ironpipeshallberequiredinanyalternative.Pleasereviewandreviseasneeded.
Response:Thedesignisforaminimumcoverof3feet.Notesandlabelsareprovidedonthissheet
toindicateaminimumcoverof3feet.
9.Comment:TheOverallPlanInfiltrationBasins&SprayAreadrawing(SheetC48)depicts
twoblocks.ArebothblocksdepictedonSheetC53,orisoneofthemlabelledin
error?TheAttachmentIinformationsheetindicatesthatnozzleinformationandair
releases/drains,andcontrolvalvesarepresentedonSheetC53.Theprovidedplansetdidnot
includeSheetC53,andwewereunabletoreviewthisinformation.Pleaseprovidethemissing
sheetandreviewandreviseSheetC48,ifnecessary.
Response:BothblocksareprovidedonSheetC53.SheetC53hasbeenattached.
10.Comment:PerSheetC56,thedepictedfieldislabelledasFieldNo.14Area(EastSide),but
basedontheprovidednortharrowandtheoverallmaponSheetC48itappearstobethe
westernportionoftheproposedfield.Pleasereviewandrevise.

Ms.RaupPlummer
October4,2021
Page9
Response:Thishasbeencorrectedandbothdrawingsattached.
11.Comment:SomeofthefieldgeometriesdepictedonSheetsC56andC57arenotattainable
withradialsprayheads,anditisunclearwhether360ºsprayheadsaretheonlytype
proposed.Thepermittedfieldacreageistobebasedonboththewettedareaofsoilssuitable
forirrigationandlimitsduetothesetbackslistedin15ANCAC02T.0506.Pleaserevisethe
fieldacreagetoaccountfortheachievablewettedarea.Pleasereviewandrevisethe
engineeringdocumentsaccordingly.
Response:Sprayapplicationfieldgeometrieshavebeenmodifiedwithrevisedwettedarea.
12.Comment:PerthesubmittedPlanSheetsitappearsthattheproposedsprayfieldsaretobe
automaticallyactivated.Hasarainormoisturesensorbeenincludedinthedesigntoprevent
irrigationduringprecipitationeventsorwetconditionsthatwouldcauserunoff,per15A
NCAC02T.0505(x)?
Response:The sprayfieldswillbeactivatedmanuallybyoperators.Theywillnotbeactivated
automatically.Araingaugeislocatedattheoperationsbuildingwhichwillbeusedtodetermine
precipitationeventsandpreventirrigationduringwetconditions.
13.Comment:PerSheetM1,therearecalloutsforthe12inchbypasslineslocatednearthe
manualbarscreenandtherotarydrumscreen.PerSheetM2,thesebypasslinesappearto
connecttotheinfluent12inchDIPforcemainrefertoSheetC15.SheetC15wasnotprovided,
anditisunclearwherethesebypasslines(notlistedintheapplicationform)areflowingto.
Pleasenotethatpursuantto15ANCAC02T.0505(j)bypassandoverflowlinesshallbe
prohibited.Pleaseprovideadditionalinformationandreviewandreviseasneeded.
Response:Thebypassestheinfluentflowmetersintheeventthattheyneedtobe
removedforservicingorreplacement.Thedischargeofthesebypassmetersisupstreamofthescreen
andwillreceivefulltreatment.
14.Comment:Withintheplansheets,theheadworkshavebeenroutinelypackagedasasingular
unit(asshownonthehydraulicprofilesandwithintheCsheets).Duetothecompactnature
ofthedesign,andthenumerousprovidedsectionviews,itisabitdisorientingtofollowthe
influentflowpaththroughtheproposedsystem.Aqualitativewalkthroughwasprovided
withintheengineeringcalculations;however,avisualoftheflowpathwouldbebeneficialto
ourreview.Pleaseprovidealinearflowpaththatincludescalloutsforthedifferenttreatment
unitstohelpclarifytheproposedsystemdesign.

Ms.RaupPlummer
October4,2021
Page10
Response:AflowpathhasbeenaddedtotheM2Sheet.
15.Comment:WithinDetail3onSheetM3abypassisidentifiedinthevicinityofthejibcrane
withinthesection.Itisunclearwherethisbypassislocatedasitdoesnotappeartobecalled
outonSheetsM1orM2.Pleasenotethatpursuantto15ANCAC02T.0505(j)bypassand
overflowlinesshallbeprohibited.Pleaseprovideadditionalinformationandreviewand
reviseasneeded.
Response:Thisisagritchamberbypasstobeusedifmaintenanceisrequiredonthegritchambers.
16.Comment:ThedetailsdepictedonSheetsM3throughM5havenumeroussectionslabelled
buttheyappeartobedesignedtohighlightspecificcomponentsofthe
proposedheadworks.Pleaseconsideraddingclarificationregardingthespecificcomponents
presented.Forexample,D6onSheetM5appearstobefocusedontherotarydrumscreen.
Response:Thesectioncutsareintendedtoindicatetheareaoftheheadworkswhicheachdrawing
refersto.Nomenclatureisdictatedbytheunitprocessandthesectioncutnumber.
17.Comment:PerSheetD7,themonitoringwellconstructiondetaildoesnotdepictthe
permanentlyaffixedidentificationplateasrequiredunder15ANCAC02C.0108(p).Please
reviewandreviseasneeded.
Response:Thishasbeenadded.TheupdatedD7hasbeenattached.
18.Comment:PerSheetD7,detaildrawingsfortherelationofwaterandsewermainstostorm
sewerandtherelationofwatermainstosewermainswasdepicted;however,asimilardetail
drawingfortherelationsofreclaimedwatermainstopotablewatermainsandsewermains
wasnotincluded.Pleaseprovideadetaildrawingforreclaimedwatermainseparation
requirements.
Response:SheetD7hasbeenrevisedseeattached.
19.Comment:AportionoftheproposedmodificationincludestheremovalofFields1Aand1B.
ThePlanSetsubmitteddidnotappeartoincludedemolition/decommissioningplansforthese
fields.Willportionsbecappedandabandonedinplaceorwilltheexistinginfrastructurebe
removed?Pleaseprovideadditionalinformationandaplansheetdepictingtheextentofthe
proposedfieldremovalactivities.

Ms.RaupPlummer
October4,2021
Page11
Response:Plansheetsindicatecappingandremovalofexistingsprayarea1Aand2Bpiping.
J.Specifications:
1.Comment:Specificationsmustbesigned,sealed,anddatedbyaNorthCarolinalicensed
ProfessionalEngineeringoodstanding.PleaseprovideacertifiedcoversheetfortheProject
Specifications.
Response:Asealedspecificationscoverisattached.
2.Comment:Per0990009,thecolorcodingrequirementsincludefinishedwater,butitwas
notedthatthecolorscalledoutfortreatedwastewatereffluenttothesprayfieldsandtreated
reclaimedwatertotheinfiltrationbasinsidentifiedinthePlanSetwerenotincludedinthis
table.Pleasereviewandrevise.
Response:PleasenotethatspecificationSection099000page9hasbeenrevisedtoshowpotable
waterasdarkblue,treatedeffluentforthepurposesofnonpotablewater,infiltration,orirrigationas
purple.
3.Comment:WithinSection311000,itappearsthatnoreferenceismaderegardingprocedures
fortheidentificationandrelocationofendangeredplantspecieswithinthelimitsof
disturbanceasindicatedwithinthePlanSheets.Pleasereviewandreviseasneeded.
Response:Sectionrevised.
4.Comment:TheSpecificationsregardingSeeding(329219)onlyaddressfinalseeding,and
therequirementspredominantlyfocusonthehighrateinfiltrationbasins.Pleaseprovide
seedingrecommendationsforthesprayirrigationfieldareasandincludethetemporary
seedingrequirementsandriparianseedingrequirementsoutlinedinthePlanSheets.Please
revisetheengineeringdocumentsasnecessary.
Response:Seedingspecificationhasbeenrevisedforsprayapplicationareas.
5.Comment:WithinthedefinitionsofSection331100,theutilitycompanyislistedasLincoln
County.Pleasereviewandreviseasneeded.
Response:PleasenotethatSpecificationSection331100,WaterUtilityDistributionPipinghas
beenrevisedtoreflectBrunswickCountyasthelocalutility.

Ms.RaupPlummer
October4,2021
Page12
6.Comment:NumeroussectionsoftheSpecificationsreferenceSection407213Ultrasonic
LevelMeters;however,thissectionwasnotprovidedinthesubmittedSpecificationsset.
Pleasereviewandrevise.
Response:PleasenotethatreferencestoSpecificationSection407213UltrasonicLevelMetershave
beenremoved,andwhereappropriatereplacedwithreferencetoSpecificationSection409123.36
LiquidLevelMeasuringSystem.
K.EngineeringCalculations:
1.Comment:Withinthebasisofdesignsectionfortheinfluentpumpstation,itisunclearwhich
pumpswereselectedfortheShallotteplant.Itappearsthatthree(3)selfpriming,520GPM
variablefrequencydrive,20HPpumpsareproposedforthetransfertoMulberryBranch
WWTP,butitisunclearwhichpumpshavebeenselectedfortheotherthreepumps.Please
clarifyandreviseasneeded.
Response:Thenarrativeswithinthedesigncalculationspackagereflectthis.WithintheSystemhead
calculationssectionofthedesigncalculations,thefulldesigncriteriaforthePumpStationNo.1
pumps,arepresented.ThesepumpscanpumptoeithertheEQtankortheShallotteWWTP(lagoons).
BothScenariosaremodeled.
2.Comment:WithinthenarrativefortheSystemHeadCurveofGritPS,twoseparatescenarios
involvingusageofthegritpumpareprovided(sumppumpversusgritwasher).Thescenario
labelsonthenextpagediscussnewlevelpipeandoldpipe.Thenarrativeoftheinfluent
pumpssimilarlyliststwoscenariosbutidentifiesthemasnewversusoldpipe.AretheGrit
PSscenariolabelsinerror?Pleaseprovideadditionalinformationandreviseasneeded.
Response:Theintentwastodesignaroundthetwomostconditionsthepumpwouldface,
whichiswithbrandnewpipeandafulltankvsatotallyemptytankandoldpipe.Thisdesignapproach
ensuresthepumpswillnotbeoverloaded.
Theheadworksgritchamberistobeconstructedwithacapacityof3.125MGDpeakflow,but
expandableupto12MGDpeakflow.Onlyonegritchamberwillbeinserviceafterconstructionofthis
project.Theothergritchamberwillbeconstructed,however,willnotbeinservice.Thegritpumpswill
beinstalledwithinbothgritchambersaspartofthisproject.Thereasonforthisisthatforthe
gritchamber,thegritpumpswilloperateasintended,pumpingsettledgritoutofthebottoms
ofeachgrittank.Intheingrittank,thegritpumpwillactasasumppumptoclearout
rainwaterandleakageasneeded.Thescenarioofthispumpismoreconservative,which
iswhytheconditionwasmodeledusing

Ms.RaupPlummer
October4,2021
Page13
3.Comment:ThecalculationsfortheSprayIrrigationsystemprovideaprecipitationrateof0.13
in/hr;however,theloadingrateontheapplication(ItemVII.3)listsarateof2in/hr.Other
provideddocumentationindicatesthatapplicationwillbe0.2in/dose(nottoexceed1
in/week).Pursuantto15ANCAC02T.0505(n),theirrigationsystemdesignshallnotexceed
therecommendedprecipitationratesestablishedinthesoilsreport.Pleasereview,revise,and
provideadditionalinformationasneeded.
Response:Thisapplicationrateforcalculationsistherateatwhichwatercanbeappliedandpass
throughthesoilfreely.Theintentofourdesignwastonotexceedthisapplicationratetoavoid
waterloggingthesoil,orcausingafreestandingwatercondition.
Theistherateatwhichwaterflowsthroughanindividualsprinklerheaddivided
bytheareatowhichthesprinklerprovideswater.Thecalculationswhichderivethisnumberare
presentedintheDesignCalculationsPackage.
Theequationisasfollows:Flowrate/Distributionarea=PrecipitationRate.
TheSoilReportindicatedthatwatershouldbeappliednomorethan0.2inchesperdose,totalnomore
than1inchperweek.Usingourcalculatedprecipitationratefromtheaboveformulaof0.13inchesper
hour,wewereabletodeterminetheamountoftimethesprinklersneedtoruntoprovide0.2inchesper
doseandnotexceed1inchperweek.AllcalculationsarepresentedwithintheDesignCalculation
Package.
700gpmisthecorrectflowwhichandisusedasthebasisofdesign.Asindicatedbyourmodeling
efforts,thesystemheadcurve/pumpcurveintersectionforournewsprayfieldwillintersectataround
700gpm.Thissheethasbeenupdated.
L.SiteMap:
1.Comment:ThePlanSheetsidentifiedC3,C4,C7,C8,andC53whichwasmissingfromthe
providedsubmittaltobeconsideredasthesitemaps.Thesesheetsdidnotappeartoinclude
amapoftheexistingsprayfields.Thesitemapsareusedduringpermitwritingandshould
encompasstheentirepermittedfacility.Pleasenotethatthefinalengineeringplanswillbe
approvedseparately,andmanyapplicantschoosetocreatesitemapsseparatefromtheplan
setthatutilizebothtopographiccontourbasemapsandaerialbasemapstoassistinpointing
outkeyfeaturessuchaslagoons,sprayfields,andpropertyboundaries.Forreference,the
existingsitemapisincludedasFigure1oftheExistingPermitforWQ0000798.Please
reviewandreviseyoursitemapssothattheentirepermittedfacilityisdepicted.

Ms.RaupPlummer
October4,2021
Page14
Response:Sitemapfigureisattached.
M.PowerReliabilityPlan:
1.Comment:ThedocumentationforthePowerReliabilityPlanwasnotincludedinthe
submittal(thepdfjumpfromAttachmentLtoAttachmentP).Pleaseprovide
documentationtoindicatethattherequirementsof15ANCAC02T.0505(l)aremetforour
review.
Response:Thepowerreliabilityplanwillberesubmittedwiththisresponseforyourreview.The
powerreliabilityplanindicatesthattheproposedgeneratorissufficientlysizedtopowerallunit
processes.
N.OperationandMaintenancePlan:
1.Comment:TheOperationandMaintenance(O&M)Planwasnotincludedinthesubmittal
(thepdfjumpfromAttachmentLtoAttachmentP).PleasesubmitanO&MPlan
meetingtherequirementsof15ANCAC02T.0507forourreview.
Response:AnO&MmanualspecifictotheShallotteWWTPhasbeenadded.
O.ResidualsManagementPlan:
1.Comment:ThesubmittedResidualsManagementPlanwaspreparedfortheMulberry
BranchWWTPandnottheShallotteWWTF.PleaseprovidetheResidualsManagementPlan
pertinenttotheShallottefacility(WQ0000798)thatmeetstherequirementsof15ANCAC02T
.0508.
Response:Theproposedprojectshouldnotimpactthequantityofsludgeproducedwithinthe
ShallotteWWTP,soaresidualmanagementplanwasnotinitiallyproduced.Aplanhasnowbeen
generatedandattachedtoportraytheexistingpractices.
P.AdditionalDocumentation:
CertificateofPublicConvenienceandNecessity:

Ms.RaupPlummer
October4,2021
Page15
1.Notapplicable.
ExistingPermit:
1.Comment:AcopyoftheResidualsLandApplicationPermitWQ0034513;however,the
ShallottefacilityisnotlistedontheAttachmentAintheprovideddocumentdatedand
certifiedSeptember27,2016.ThemostrecentcertifiedAttachmentAisdatedMarch8,
2018.PleasenotethatShallotteWWTFiscurrentlypermittedatotalof1,500drytonsper
year.Aretheproposedmodificationsanticipatedtogenerateadditionaltonnagefromthe
Shallottelagoonsandproposedheadworks?Anincreaseindrytonnagewill
requiremodificationtotheexistingpermit.Also,residualsgeneratedbytheMulberry
Branchfacilitywillhavetobeaddedviapermitmodificationpriortodisposalvialand
applicationunderWQ0034513.
Response:AresidualsmanagementplanhasbeencreatedfortheShallotteWWTP.Thesolids
generatedinthesefacilitiesarewellbelow1,500drytonsperyear.
FinalEnvironmentalDocument:
1.Comment:ThesubmittalindicatedthatanEngineeringReport/Environmental
InformationDocumentwassubmittedonDecember17,2020;however,afinal
ruling/responsewasnotprovided.PleaseprovidetheFindingofNoSignificantImpact
(FONSI)ortheRecordofDecision(ROD)forourreview.
Response:Pleaseseeattached.
2.Comment:Section7.10oftheEnvironmentalInformationDocumentindicatedthata
Figure7.10depictingendangeredspecieswaspartofthereport.Isthisthemaptitled
ProtectedWewereunabletolocatethismapwithinthesubmitted
file.
Response:PleaseseeFigure7.10attached.
FloodwayEnvironmentalDocument:

Ms.RaupPlummer
October4,2021
Page16
1.Comment:Aportionoftheproposedsprayfieldsarelocatedwithinthe100year
floodplain.ThedocumentationofNoImpactprovidedinthesubmittalappearsto
referencetheproposedculvertconstructionatMulberryBranchanddoesnotreference
thepotentialimpactsoftheproposedwastewaterirrigationsprayfield.WithinChapter
143Article21Part6oftheGeneralStatutes,itisstatedthatalocalgovernmentmayadopt
ordinancestoregulateusesinfloodhazardareasandgrantpermitsfortheuseofflood
hazardareasthatareconsistentwiththerequirementsofthisPart.Pleaseprovidewritten
documentationfromalllocalgoverningentitiesthattheproposedfacilitymodifications
areincompliancewithalllocalordinancesregardingconstructionoroperationof
wastewatertreatmentand/ordisposalfacilitieswithinthefloodplain.
Response:Sprayapplicationareahasbeenchangedtobeoutsideofthemapped100year
floodplain.
OperationalAgreements:
1.Notapplicable.
ThreatenedorEndangeredAquaticSpeciesDocumentation:
1.Comment:AmapwasprovidedlabelledtheProtecteddocument
anditwasindicatedthatthisprojectwillnotimpactanyendangeredspecies.However,
throughouttheplansheetsthereareseveralcalloutsindicatingthelocationof
endangeredspeciesalongtheforcemainalignments.Pleaseprovideadditional
informationregardingthereferencedendangeredplantspeciesandanypertinent
documentationoftheseimpacts.
Response:Theendangeredspeciesaretoberelocatedinaccordancewiththespecifications.
WastewaterChemicalAnalysis:
1.Notapplicable.
Q.Recommendations(Responsenotrequired):
1.Comment:Withinthesubmittalpackageandsitevisit,theapplicantindicatedthataportion
oftheproposedsprayirrigationareaislocatedinaZoneA(100year)floodplain.Although
anattemptwasmadebytheapplicanttojustifytheinstallationofsprayheadsinthisarea,

FINDING OF NO SIGNIFICANT IMPACT
AND ENVIRONMENTAL ASSESSMENT
CITY OF SOUTHPORT
WASTEWATER TREATMENT AND DISPOSAL

RESPONSIBLE AGENCY:NORTH CAROLINA DEPARTMENT OF
ENVIRONMENTAL QUALITY

CONTACT: JON RISGAARD, SECTION CHIEF
STATE REVOLVING FUND SECTION
DIVISION OF WATER INFRASTRUCTURE
1633 MAIL SERVICE CENTER
RALEIGH, NORTH CAROLINA 27699-1633
[phone]
September 28, 2021

(This page intentionally left blank.)

FINDING OF NO SIGNIFICANT IMPACT
Article I, Chapter 113A of the North Carolina General Statutes requires an action to be subject to
the requirements of the North Carolina Environmental Policy Act (NCEPA) if it involves the
expenditure of public funds and if a potential impact is anticipated to the environment. The
project has been evaluated for compliance with the NCEPA and is determined to be a major
agency action, which will affect the environment.

Project Applicant:
City of Southport, North Carolina
Project Description:The proposed project is intended to provide long-term wastewater
treatment and disposal for the City of Southport through
Brunswick County facilities. The project will construct a new
0.75 million gallons per day (MGD) extended aeration tertiary
treatment facility at the County-owned Shallotte wastewater
treatment plant (WWTP) site. Metered flow will be diverted from
the existing West Brunswick Water Reclamation Facility
(WBWRF) to this new plant, which will allow for treatment of
flow from Southport at the WBWRF. The City will purchase0.75
MGD permanentcapacity in the County’s existing forcemain to
convey wastewater from the City to the WBWRF. The proposed
project will include construction of a new forcemain to convey
flow from existing regional transmission mains to the proposed
WWTP. The existing 0.5 MGD Shallotte WWTP will remain in
operation with flow entering the site through a single pump
station and headworks and then divided between the existing
WWTP and the proposed new WWTP.
Project Number:
CS370714-03
Project Cost:
$30,451,306
Clean Water State
$29,783,014
Revolving Loan Fund:
Local Funds:
$668,292
The review process indicated that significant adverse environmental impacts should not occur if
mitigative measures are implemented, and an environmental impact statement will not be
required. The decision was based on information in the Engineering Report/Environmental
Information Document (ER/EID) submitted by the applicant and reviews by governmental
agencies. The attached Environmental Assessment (EA), prepared by the Division based on the
ER/EID,supports this action andoutlines mitigative measures that must be followed.This
Finding of No Significant Impact (FONSI) completes the environmental review record, which is
available for inspection at the State Clearinghouse.

No administrative action will be taken on the proposed project for at least 30 days after
notification that the FONSI has been published in the North Carolina Environmental Bulletin.
Sincerely,
Jon Risgaard, Section Chief
State Revolving Fund Section
Division of Water Infrastructure

ENVIRONMENTAL ASSESSMENT
A. Proposed Facilities and Actions
The proposed project is intended to provide a long-term solution for wastewater treatment and
disposal for the City of Southport through an agreement with Brunswick County and other
partners of the West Brunswick Water Reclamation Facility (WBWRF). The proposed project
will construct a new 0.75 million gallons per day (MGD) regional wastewater treatment plant
(WWTP) at the County-owned Shallotte WWTP site. This new WWTP will treat wastewater
flow that is currently pumped from the southeastern portion of Brunswick County to the West
Brunswick Water Reclamation Facility (WBWRF). A metered flow of 0.75 MGD from the
southern portion of the County will be redirected to the proposed new WWTP at the Shallotte
site. The City will purchase permanent capacity in the existing County-owned transmission main
from Southport to the WBWRF along NC 211. Redirecting flow from the WBWRF to the new
WWTP will allow for treatment of additional flow from the City at the existing WBWRF. The
existing 0.5 MGD Shallotte WWTP on the property will remain in operation. Two spray
irrigation fields will be relocated on the property to accommodate the new facility.
The project will include a new 0.75 MGD high-rate infiltration system and a new forcemain to
convey wastewater from the existing regional transmission mains on US 17 to the new facility on
the Shallotte site. Wastewater influent from multiple forcemains will be pumpedthrough a single
influent pump station and headworks. From there, flow will be split between the existing 0.5
MGD lagoon WWTP and the proposed 0.75 MGD new plant. The new WWTP will be an
extended aeration tertiary treatment facility including the following components: influent
headworks; forced vortex grit removal system; two-chamber equalization basin; influent splitter
boxes and piping; two oxidation ditches with rotors and submersible mixers; two circular
secondary clarifiers; RAS/WAS pump station; two 2-disk cloth media filter units sized for peak
flow; two chlorine contact tanks for disinfection with sodium hypochlorite; reclaimed water
pump station to convey flow to the on-site disposal area; non-potable water pumps and pipping
for facility and screening wash; 3.75 MGD upset pond and associated return pump station and
pumping to return upset flow to the head of the plant; one aerobic digestion tank; tank for sludge
storage/lime stabilization; effluent disposal facilities including infiltration ponds; building
structures; facilities to offload materials with high solids; piping and valves to reroute influent to
headworks; odor control equipment and enclosures, and in-plant piping. Treated effluent will be
disposed through three high rate infiltration basins. A groundwater management drain will be
constructed around the infiltration basins to control groundwater mounding. Groundwater will be
drained by gravity to two level spreaders. A wetland monitoring plan will be implemented to
monitor and manage groundwater mounding and dewatering of adjacent wetland areas.
Funding Status: The estimated total cost for the project is $30,451,306. The Town is applying for
a Clean Water State Revolving Fund (CWSRF) loan of $29,783,014. Closing
costs/administrative fees of $668,292 will be paid with local funds.

1

B. Existing Environment
Topography and Soils. The City of Southport and Brunswick County are located in the Coastal
Plain Physiographic Province. The elevation of the project site ranges from 32 to 68 feet above
mean level. The project site is located in the Waccamaw Formation geologic unit, which consists
of flood plain deposits with sand at or near the surface. Much of the Shallotte plant property
includes floodplains, but the proposed plant and spray fields will avoid these areas.
The dominant soilseries in the project area are Kureb fine sand and Baymeade fine sand. Almost
seventy percent of the project area consists of Kureb fine sand with slopes from one to eight
percent. Approximately 13% of the project area is Baymeade fine sand with slopes between one
and six percent.
Surface Water. The WWTP site is located in the Lower Lumber River Basin (HUC 03040207).
Mulberry Branch (designated as Class C, high quality, swamp water) runs adjacent to the spray
fields. Woodward Branch (designated as Class C, high quality, swamp water) is located
immediately south of the project area. The Intracoastal Waterway is approximately 6 miles south
of the project site and is listed as impaired for exceeding shellfish harvesting criteria with a
“conditionally approved – open” rating. Brunswick County is subject to the state Coastal Area
Management Act (CAMA). The Shallotte River is the nearest protected tidal salt water. It is
located 1.7 miles south of the proposed WWTP and 1.2 miles south of the southern end of the
proposed forcemain.
Water Supply. The primary sources of drinking water for Brunswick County are the Cape Fear
River and the Castle Hayne Aquifer. The Northwest Water Treatment Plant located in the Leland
area treats water from the Cape Fear River. The 211 Water Treatment Plant in Southport treats
groundwater from 14 wells drawing from the Castle Hayne aquifer.
C. Existing WastewaterFacilities
The City operates their own wastewater collection system to collect wastewater within city limits
and the extraterritorial jurisdiction. In 2009, the City entered into an interlocal agreement to use
capacity from Brunswick County in the West Brunswick Regional Wastewater System. The
agreement allowed the City to lease capacity from the County until flows require expansion of
facilities, at which time the City would be required to purchase capacity. The City’s Central
pump station collects wastewater from the sewer basin, and the Sandy Plane pump station pumps
flow to the County system through a 19,995 linear feet (ft) 16-inch forcemain. When
construction of the pump station and forcemain were completed in 2011, the City
decommissioned their own wastewater treatment facilities and routed wastewater flow to
Brunswick County. The City entered into a long-term agreement with the County in 2017 and
updated the agreement in 2020 for purchase of treatment and disposal capacity in the regional
system.

The West Brunswick Regional Wastewater System provides service for the Town of Holden
Beach, the Town of Oak Island, the Town of Shallotte, and Brunswick County. Treatment
facilities include the 6.0 MGD WBWRF located in Supply, NC, and the 0.5 MGD Shallotte
2

WWTP. The regional system includes forcemain transmission from the southern part of the
county along US 17 and from the east along NC 211. The WBWRF (Permit # WQ0023693) is a
tertiary treatment system originally constructed in 2003 with capacity of 3.0 MGD and expanded
to the current 6.0 MGD capacity in 2009. Current 12-month average daily flow is approximately
3.811 MGD. The Shallotte WWTP (Permit # WQ00008-A and B) is a facultative lagoon process
with on-site spray irrigation disposal with capacity of 0.5 MGD and current 12-month average
daily flow of 0.195 MGD. The partners in the regional system have dedicated capacity through
interlocal agreements. The City of Southport has leased capacity since 2007.

D. Need for Proposed Facilities and Actions
The City of Southport has leased capacity in the West Brunswick Regional Wastewater System
since 2007 but does not have dedicated capacity. The City needs long-term wastewater treatment
and disposal capacity to satisfy existing needs and anticipated growth. Based on population
projectionsand flow analysis, the current flows of 0.491 MGD are projected to increase to 0.75
MGD during the 20-year planning period. The City needs to secure forcemain allocation and
treatment capacity for this flow. The existing transmission main is sufficient to meet this need,
but the County will upgrade the main in the future to accommodate the County’s needs.
Southport will pay Brunswick County for capacity allocation in the transmission system.
E. Alternatives Analysis
No-Action Alternative: This alternative would continue operation of the existing facilities
without change, and would result in the WBWRF becoming overburdened with increasing flow,
increased operations and maintenance costs for exceedance of plant design capacity, and permit
violations. This alternative is rejected because itdoes not meet the need for additional treatment
capacity.
Alternative 1 – New WWTP at Shallotte Site: This alternative would construct a new 0.75 MGD
high-rate infiltration system at the site of the existing Shallotte WWTP. Under this alternative,
0.75 MGD of flow would be redirected from the WBWRF to the new facility to accommodate
the additional 0.75 MGD needed for Southport at the WBWRF. The new plant will include
influent headworks; forced vortex grit removal system; two-chamber equalization basin; influent
splitter boxes and piping; two oxidation ditches with rotors and submersible mixers; two circular
secondary clarifiers; RAS/WAS pump station; two 2-disk cloth media filter units sized for peak
flow; two chlorine contact tanks for disinfection with sodium hypochlorite; reclaimed water
pump station to convey flow to the on-site disposal area; non-potable water pumps and pipping
for facility and screening wash; 3.75 MGD upset pond and associated return pump station and
pumping to return upset flow to the head of the plant; one aerobic digestion tank; tank for sludge
storage/lime stabilization; effluent disposal facilities including infiltration ponds; building
structures; facilities to offload materials with high solids; piping and valves to reroute influent to
headworks; odor control equipment and enclosures, and in-plant piping. This is the preferred
alternative because it meets the need for additional treatment capacity while minimizing
environmental impact to local aquifers and reducing pumping needs for effluent transmission
compared to other alternatives.
3

Alternative 2 – New WWTP at Southport Site: This alternative would construct a new Southport
WWTP. The plant constructed under this alternative would be a 0.75 MGD high-rate infiltration
plant with similar components as Alternative 1. The Southport site is within the Military Ocean
Terminal Sunny Point Blast Zone, which increases the risk of suspended operation due to an
accident that could leave raw sewage untreated. The hydrologic conditions at this site pose a risk
of infiltration contamination to the Castle Hayne Aquifer. Due to the risks associated with this
site, this alternative is rejected.
Alternative 3 – Expansion of the Existing WWTP at WBWRF: This alternative would expand
the WBWRF by adding a new oxidation ditch treatment train in parallel with the existing
process. This alternative would also require constructing effluent forcemains to the Shallotte site
for infiltration, which would increase environmental impacts due to the land disturbance required
for construction. This alternative is rejected due to the increased cost and environmental impacts
associated with the transmission of effluent to the Shallotte site.
F. Environmental Consequences and Mitigative Measures
Topography and Soils: Construction activities will have limited impacts to topography and soils
and no permanent impact to FEMA-jurisdictional floodplain areas. The proposed WWTP and
infiltration basins will be constructed outside of floodplain areas, but some transmission lines
will cross floodplains. A No-Rise certification was completed, and permits for work in
floodplains will be obtained. Some permanent grading will be required for construction of the
WWTP and infiltration basins; other construction areas will be returned to existing conditions.
The infiltration basins will include earthen berms. Construction impacts will include some soil
disturbance. Soils will be returned to original location or removed from the site as appropriate. A
DEQ-approved Erosion and Sedimentation Control Plan will be followed. Secondary and
cumulative impacts (SCI) related to growth will be minimized through compliance with
Brunswick County’s Flood Damage Prevention Ordinance.
Land Use: No impacts to land use are anticipated. Construction will occur within the existing
WWTP site in an area that is already zoned for Heavy Industrial. SCI will be minimized through
compliance with the CAMA Land Use Plan, and through zoning district requirements established
in the County’s Unified Development Ordinance (UDO).
Wetlands: Significant impacts to wetlands are not anticipated. Installation of transmission lines
and forcemain will have temporary impacts to 0.22 acre and permanent impacts to 0.15 acre. No
impacts are anticipated for construction of the WWTP, spray fields, or infiltration basins. A
Jurisdictional Determination will be submitted to the U.S. Army Corps of Engineers (USACE),
and design footprints will be altered to minimize impacts to wetlands to the extent practicable.
Impacts to wetland hydrology adjacent to the infiltration basins will be evaluated using
monitoring wells, with adjustments made as necessary to minimize impacts to wetland
hydrology. Spray fields will be located a minimum of 100 feet from wetlands, and high rate
infiltration basins will be located at least 200 feet from wetlands. Upon completion of design, a
Pre-Construction Notification will be submitted to the USACE. If mitigation is required based on
the final total of unavoidable, permanent impacts, mitigation credits will be purchased through
4

an existing private mitigation bank or the NC Division of Mitigation Services. SCI will be
minimized through compliance with buffer requirements, greenways, and planning requirements.
Important Farmlands: Significant impacts to important farmlands are not anticipated. The project
area does not include designated prime and unique farmlands. Secondary and cumulative impacts
will be minimized through efforts of the County’s Agricultural Advisory Board and Agricultural
Preservation Program.
Public Lands and Scenic, Recreational, and State Natural Areas: Impacts to public lands, scenic,
recreational, or state natural areas are not expected. No such areas are located in or near the
project area. SCI will be minimized through compliance with the UDO and the Viewshed
Protection Overlay, which is intended to protect the scenic characteristics of the County.
Cultural Resources: Impacts to cultural and historic resources are not anticipated. The North
Carolina State Historic Preservation Office (SHPO) is not aware of any historic resources that
will be impacted by the project (May 1, 2018, ER 18-0647). No areas of archaeological or
historical value have been identified in the immediate project area. SCI will be minimized
through compliance with the UDO and review of historic resources, which are identified in the
County’s records.
Air Quality: No significant impacts to air quality are anticipated. Construction activities will
have temporary impacts related to particulates and dust as well as exhaust emissions from
construction equipment. Construction equipment will have emission controls to minimize
impacts. The WWTP may produce odor impacts in the immediate vicinity. The location was
chosen to maximize distance from residential areas, and the headworks facility will be equipped
with an odor control system to minimize any impact from odors. The WWTP will include a
diesel generator which will be operated in compliance with Division of Air Quality requirements.
Noise Levels:No significant permanent noise impacts are anticipated. Construction activities
will be limited to daylight hours (weekdays from 7:00 am to 6:00 pm). The WWTP operations
may result in a slight increase in noise levels which is offset by distance from adjacent
properties. SCI will be minimized through compliance with noise ordinances and buffer
requirements established in the UDO.
Water Resources: No significant impacts to water resources are anticipated. Effluent
transmission lines will be installed using horizontal directional drilling at all stream crossings. To
avoid permanent impacts to Mulberry Creek, a bridge will be installed to provide access to the
infiltration basins from the WWTP site.Best Management Practices will be followed to
minimize erosion and sediment loss from construction. Backfilled soil will be stabilized by
seeding and mulching. A DEQ-approved Erosion and Sedimentation Control Plan will be
followed. The proposed infiltration basin has been evaluated and designed with drain system to
control mounding so that no negative impacts to groundwater are anticipated. Designated coastal
resources are not located within the project area and will not be impacted. SCI will be minimized
through the UDO’s Water Quality Protection Overlay Zone and associated requirements that
limit impervious areas, require buffer zones, and impose additional restrictions to protect water
quality.
5

Forest Resources:Significant impacts to forest resources are not expected. Construction will
impact forested areas that are part of active, maintained spray fields rather than true forest
resources. Permanent impacts will include 12 acres for construction of the WWTP and 30 areas
for the infiltration basins. SCI will be minimized through the County’s UDO, which includes
requirements for a tree survey before development, restricts clear cutting, and provides additional
measures to protect trees and forest resources.
Shellfish or Fish and Their Habitats:Significant impacts to shellfish, fish, and their habitats are
not expected. There is no evidence of threatened or endangered species or habitats in the project
area. Impacts to aquatic species will be minimized through Best Management Practices. SCI will
be minimized through the UDO’s Water Quality Protection Overlay Zone and associated
requirements that limit impervious areas, require buffer zones, and impose additional restrictions
to protect water quality.
Wildlife and Natural Vegetation: No significant impacts to wildlife and natural vegetation are
expected. Formal spring, summer, and fall species-specific surveys were conducted to identify
protected species. Six populations of the threatened Lachnocaulon minus (Small’s bogbutton)
were identified adjacent to access road/transmission line alignment. Impacts will be minimized
by adjusting alignment during final design, to the extent practicable, to avoid these populations.
Where rerouting is not possible, colonies will be hand-excavated and transplanted to suitable
habitat adjacent to existing locations that will not be impacted. Formal surveys for the red-
cockaded woodpecker were also conducted with none found.
Introduction of Toxic Substances:The project is not expected to introduce toxic substances into
the environment. Dumping of chemicals, fuels, lubricants, etc. will be prohibited. Provisions in
the construction contract will require the contractor to exercise every reasonable precaution
during construction to prevent pollution. If more than 220 pounds of hazardous materials are
generated per calendar month during site preparation, DEQ’s Hazardous Waste Section will be
notified and requirements for large quantity generator will be followed. Upon completion, the
WWTP may use chlorine, alum, and lime as part of the treatment process and will store diesel
fuel and petroleum-based lubricants for power generation and equipment maintenance. Storage
of materials will be in compliance with local, state, and federal regulations.
The U.S. Fish and Wildlife Service reviewed the proposed project and comments were resolved
(January 14, 2021). The North Carolina Wildlife Resources Commission, Natural Heritage
Program, and DWR Wilmington Regional Office do not object to the proposed project. The U.S.
Army Corps of Engineers was consulted and did not object to the project. The North Carolina
Department of Natural and Cultural Resources is aware of no historic resources that would be
affected by the project(May1, 2018, ER 18-0647).

G. Public Participation, Sources Consulted
A public meeting was held with representatives from both the City of Southport and Brunswick
County on August 24, 2021 and made the engineering report/environmental information
6

document available for review by the public through both the City Hall and the County’s public
utilities office. the City’s website. There was one question from public:
Question: When will the project get started?
o Response: Permit applications have been submitted, bid date is scheduled
between Thanksgiving and Christmas, and the project is anticipated to be
completed in the Fall of 2023.

The current user charge for a typical residential customer for the City of Southport is $126.40 per
month for water and sewer service combined, based on consumption of 5,000 gallons per month.
The proposed project will increase the bill by $5.09 (approximately 4%), for a future combined
bill of $131.49.
Sources consulted about this project for information or concurrence included:
1) City of Southport
2) Brunswick County
3) North Carolina Department of Environmental Quality
-Wildlife Resources Commission
-Natural Heritage Program
-DEQ Wilmington Regional Office
-Division of Air Quality
-Division of Water Resources
-Division of Forest Resources
-Division of Environmental Assistance and Customer Service
-Division of Waste Management
4) North Carolina Department of Natural and Cultural Resources
7) North Carolina State Clearinghouse
8) North Carolina Department of Public Safety
9) U.S. Fish and Wildlife Service
10) U.S. Army Corps of Engineers
7

U.S. ARMY CORPS OF ENGINEERS
WILMINGTON DISTRICT
Action Id. SAW-2021-01545 County: Brunswick County U.S.G.S. Quad: Shallotte
GENERAL PERMIT (REGIONAL AND NATIONWIDE) VERIFICATION
Permittee: John Nichols
Brunswick County Public Utilities
Address: PO Box 249
Bolivia NC, 28422
Telephone Number: [phone]
E-mail Address: [e-mail]
Size (acres) 693 acres Nearest Town Shallotte, NC
Nearest Waterway Woodward Branch River Basin Lower Pee Dee
USGS HUC 03040208 Coordinates Latitude: 33.99733
Longitude: -78.37622
Location description: This site has an existing wastewater treatment plant and related facilities on it. The project is located on
forest Street NW in Shallotte, Brunswick County, NC. (Parcel ID’s 18100072 & 1820004217).
Description of projects area and activity: The purpose and need for this project is to construct a new regional wastewater
treatment plant. The impacts associated with this project will be: Temporary Impacts Include: 0.032 acres of wetland impacts
& 30 LF of impacts in Mulberry Branch. Permanent Impacts Include: 0.324 acres of wetland impacts & 16 LF of impacts to
Mulberry Branch for a road crossing. To offset the permanent wetland impacts, 0.7 Riparian Wetland credits will be
purchased from the Stone Farm Mitigation Bank.
Applicable Law: Section 404 (Clean Water Act, 33 USC 1344)
Section 10 (Rivers and Harbors Act, 33 USC 403)
Authorization: Regional General Permit Number and/or Nationwide Permit Number: 39 Commercial Development
58 Utility Line Activities
SEE ATTACHED RGP or NWP GENERAL, REGIONAL AND/OR SPECIAL CONDITIONS
Your work is authorized by the above referenced permit provided it is accomplished in strict accordance with the attached
conditions and your submitted application and attached information dated September 29, 2021 Any violation of the attached
conditions or deviation from your submitted plans may subject the permittee to a stop work order, a restoration order, a Class
I administrative penalty, and/or appropriate legal action.
This verification will remain valid until the expiration date identified below unless the nationwide and/or regional general permit
authorization is modified, suspended or revoked. If, prior to the expiration date identified below, the nationwide and/or regional
general permit authorization is reissued and/or modified, this verification will remain valid until the expiration date identified below,
provided it complies with all requirements of the modified nationwide permit. If the nationwide and/or regional general permit
authorization expires or is suspended, revoked, or is modified, such that the activity would no longer comply with the terms and
conditions of the nationwide permit, activities which have commenced (i.e., are under construction) or are under contract to
commence in reliance upon the nationwide and/or regional general permit, will remain authorized provided the activity is completed
within twelve months of the date of the nationwide and/or regional general permit’s expiration, modification or revocation, unless
discretionary authority has been exercised on a case-by-case basis to modify, suspend or revoke the authorization.
Activities subject to Section 404 (as indicated above) may also require an individual Section 401 Water Quality Certification. You
should contact the NC Division of Water Resources (telephone [phone]) to determine Section 401 requirements.
For activities occurring within the twenty coastal counties subject to regulation under the Coastal Area Management Act (CAMA),
prior to beginning work you must contact the N.C. Division of Coastal Management in Wilmington, NC.

SAW-2021-01545
This Department of the Army verification does not relieve the permittee of the responsibility to obtain any other required Federal,
State or local approvals/permits.
If there are any questions regarding this verification, any of the conditions of the Permit, or the Corps of Engineers regulatory
program, please contact Gary Beecher at [phone] or [e-mail].
Ejhjubmmz!tjhofe!cz!Hbsz!I/!
Cffdifs!
Hbsz!I/!Cffdifs
Ebuf;!3132/1:/3:!1:;26;51!.15(11(
Corps Regulatory Official: __________________________________________ Date: September 29, 2021
Expiration Date of Verification: NWP 39 will expire on March 15, 2026
A.Determination of Jurisdiction:
1. There arewaters, including wetlands, on the above described project areathat may be subject to Section 404 of the
Clean Water Act (CWA) (33 USC § 1344) and/or Section 10 of the Rivers and Harbors Act (RHA) (33 USC § 403). This
preliminary determination is not an appealable action under the Regulatory Program Administrative Appeal Process
(Reference 33 CFR Part 331). However, you may request an approved JD, which is an appealable action, by contacting
the Corps district for further instruction. Please note, if work is authorized by either a general or nationwide permit,
and you wish to request an appeal of an approved JD, the appeal must be received by the Corps and the appeal process
concluded prior to the commencement of any work in waters of the United States and prior to any work that could alter
the hydrology of waters of the United States.
2. There are Navigable Waters of the United States within the above described project area subject to the permit requirements
of Section 10 of the Rivers and Harbors Act (RHA) (33 USC § 403) and Section 404 of the Clean Water Act (CWA) (33 USC §
1344). Unless there is a change in the law or our published regulations, this determination may be relied upon for a period not to
exceed five years from the date of this notification.
3. There are waters, including wetlands, within the above described project area that are subject to the permit requirements of
Section 404 of the Clean Water Act (CWA) (33 USC § 1344). Unless there is a change in the law or our published regulations,
this determination may be relied upon for a period not to exceed five years from the date of this notification.
4. A jurisdiction determination was not completed with this request. Therefore, this is not an appealable action. However, you
may request an approved JD, which is an appealable action, by contacting the Corps for further instruction.
5. The aquatic resources within the above described project area have been identified under a previous action. Please reference
the approved jurisdictional determination issued . Action ID: SAW- .
B.Basis For Jurisdictional Determination:An approved JD was not issued with this action.
C.Remarks:This project was desk-top reviewed using information from the consultant (WK Dickson) and Corps generated
Lidar Maps, topographic maps and soils maps.
D.Attention USDA Program Participants
This delineation/determination has been conducted to identify the limits of Corps’ Clean Water Act jurisdiction for the particular site
identified in this request. The delineation/determination may not be valid for the wetland conservation provisions of the Food Security
Act of 1985. If you or your tenant are USDA Program participants, or anticipate participation in USDA programs, you should request
a certified wetland determination from the local office of the Natural Resources Conservation Service, prior to starting work.
E.Appeals Information for Approved Jurisdiction Determinations (as indicated in A2 and A3 above).
If you object to this determination, you may request an administrative appeal under Corps regulations at 33 CFR Part 331. Enclosed
you will find a Notification of Appeal Process (NAP) fact sheet and Request for Appeal (RFA) form. If you request to appeal this
determination you must submit a completed RFA form to the following address:
US Army Corps of Engineers
South Atlantic Division
Attn: Philip Shannin, Appeal Review Officer
60 Forsyth Street SW, Room 10M15

SAW-2021-01545
Atlanta, Georgia 30303-8801
Phone: [phone]
In order for an RFA to be accepted by the Corps, the Corps must determine that it is complete, that it meets the criteria for appeal
under 33 CFR part 331.5, and that it has been received by the Division Office within 60 days of the date of the NAP. Should you
decide to submit an RFA form, it must be received at the above address by N/A.
It is not necessary to submit an RFA form to the Division Office if you do not object to the determination in this
correspondence.
Ejhjubmmz!tjhofe!cz!Hbsz!I/!Cffdifs!
Hbsz!I/!Cffdifs
Ebuf;!3132/1:/3:!1:;26;32!.15(11(
Corps Regulatory Official: ______________________________________________________
Gary Beecher
Date of JD: September 29, 2021 Expiration Date of JD: PJD does not expire
The Wilmington District is committed to providing the highest level of support to the public. To help us ensure we
continue to do so, please complete our Customer Satisfaction Survey, located online at
http://corpsmapu.usace.army.mil/cm_apex/f?p=136:4:0.
Copy furnished via e-mail to:
Daniel Zurlo
WK Dickson
1213 West Morehead Street
Charlotte, NC 28208
[phone]
[e-mail]

SAW-20
SPECIAL CONDITIONS
Erosion Control: The permittee shall employ all sedimentation and erosion control measures
necessary to prevent an increase in sedimentation or turbidity within waters and wetlands outside
the permit area. This shall include, but is not limited to, the immediate installation of silt fencing
or similar appropriate devices around all areas subject to soil disturbance or the movement of
ear
then fill, and the immediate stabilization of all disturbed areas. Additionally, the project must
remain in full compliance with all aspects of the Sedimentation Pollution Control Act of 1973
(North Carolina General Statutes Chapter 113A Article 4).
Work Limits: All work authorized by this permit shall be performed in strict compliance with the
attached permit plans dated , whichare a part of this permit.ThePermittee
shallensure that the construction design plans for this project do not deviate from the permit plans
attached to this authorization. Any modification to the attached permit plans must be approvedby
the U.S. Army Corps of
Engineers (Corps) prior to any active construction in waters orwetlands.
Mitigation: In order to compensate for impacts associated with this permit, mitigation shall be
provided in accordance with the provisions outlined on the most recent version of the attached
Compensatory Mitigation Responsibility Transfer Form. The requirements of this form,including
any special conditions listed on the form, are hereby incorporated as special conditionsof this
permit authorization.

Action ID Number:SAW-2021-01545County:Brunswick County

Permittee: John Nichols
Brunswick County Public Utilitiies

Project Name: Mulberry Branch Water Reclamation Facility
Date Verification Issued: September 29, 2021
Project Manager: Gary Beecher
Upon completion of the activity authorized by this permit and any mitigation required by the permit,
sign this certification and return it to the following address:
US ARMY CORPS OF ENGINEERS
WILMINGTON DISTRICT
Attn: Gary Beecher

Please note that your permitted activity is subject to a compliance inspection by a U. S. Army Corps of
Engineers representative. Failure to comply with any terms or conditions of this authorization may
result in the Corps suspending, modifying or revoking the authorization and/or issuing a Class I
administrative penalty, or initiating other appropriate legal action.

I hereby certify that the work authorized by the above referenced permit has been completed in
accordance with the terms and condition of the said permit, and required mitigation was completed in
accordance with the permit conditions.

_______________________________________ ______________________
Signature of Permittee Date

U.S. ARMY CORPS OF ENGINEERS
Wilmington District
Compensatory Mitigation Responsibility Transfer Form

Permittee:John Nichols (Brunswick County Public Utilities)Action ID:SAW-2021-01545
Project Name: Mulberry Branch WWTP County: Brunswick

Instructions to Permittee: The Permittee must provide a copy of this form to the Mitigation Sponsor, either an approved
Mitigation Bank or the North Carolina Division of Mitigation Services (NCDMS), who will then sign the form to verify the
transfer of the mitigation responsibility. Once the Sponsor has signed this form, it is the Permittee’s responsibility to ensure
that Wilmington District Project Manager identified on page two is in receipt of a signed copy of this form before conducting
authorized impacts, unless otherwise specified below. If more than one Mitigation Sponsor will be used to provide the
mitigation associated with the permit, or if the impacts and/or the mitigation will occur in more than one 8-digit Hydrologic
Unit Code (HUC), multiple forms will be attached to the permit, and the separate forms for each Sponsor and/or HUC must
be provided to the appropriate Mitigation Sponsors.

Instructions to Sponsor: The Sponsor verifies that the mitigation requirements (credits) shown below have been released
and are available at the identified site. By signing below, the Sponsor is accepting full responsibility for the identified
mitigation, regardless of whether they have received payment from the Permittee. Once the form is signed, the Sponsor
must update the bank ledger and provide a copy of the signed form and the updated ledger to the Permittee, the Project
Manager who issued the permit, the Bank Project Manager, and the District Mitigation Office (see contact information on
page 2). The Sponsor must also comply with all reporting requirements established in their authorizing instrument.

Permitted Impacts and Compensatory Mitigation Requirements

Permitted Impacts Requiring Mitigation*: 8-digit HUC and Basin: 03040208, Lumber River Basin
Stream Impacts (linear feet) Wetland Impacts (acres)
Warm CoolColdRiparian RiverineRiparian Non-Riverine Non-RiparianCoastal
.324
*If more than one mitigation sponsor will be used for the permit, only include impacts to be mitigated by this sponsor.

Compensatory Mitigation Requirements: 8-digit HUC and Basin: 03040208, Lumber River Basin
Stream Mitigation (credits)WetlandMitigation (credits)
Warm CoolCold Riparian Riverine Riparian Non-Riverine Non-RiparianCoastal
0.7

Mitigation Site Debited: Stone Farm Mitigation Bank
(List the name of the bank to be debited. For umbrella banks, also list the specific site. For NCDMS, list NCDMS. If the NCDMS
acceptance letter identifies a specific site, also list the specific site to be debited).

Section to be completed by the Mitigation Sponsor

Statement of Mitigation Liability Acceptance: I, the undersigned, verify that I am authorized to approve mitigation
transactions for the Mitigation Sponsor shown below, and I certify that the Sponsor agrees to accept full responsibility for
providing the mitigation identified in this document (see the table above), associated with the USACE Permittee and Action
ID number shown. I also verify that released credits (and/or advance credits for NCDMS), as approved by the Wilmington
District, are currently available at the mitigation site identified above. Further, I understand that if the Sponsor fails to provide
the required compensatory mitigation, the USACE Wilmington District Engineer may pursue measures against the Sponsor to
ensure compliance associated with the mitigation requirements.

Mitigation Sponsor Name:

Name of Sponsor’s Authorized Representative:

Signature of Sponsor’s Authorized Representative Date of Signature
Page 1 of 2 Form Date July 7, 2020

USACE Wilmington District
Compensatory Mitigation Responsibility Transfer Form, Page 2

Conditions for Transfer of Compensatory Mitigation Credit:
Once this document has been signed by the Mitigation Sponsor and the District is in receipt of the signed form, the
Permittee is no longer responsible for providing the mitigation identified in this form, though the Permittee remains
responsible for any other mitigation requirements stated in the permit conditions.
Construction within jurisdictional areas authorized by the permit identified on page oneof this formcan begin only after
the District is in receipt of a copy of this document signed by the Sponsor, confirming that the Sponsor has accepted
responsibility for providing the mitigation requirements listed herein. When NCDMS provides mitigation for authorized
impacts conducted by the North Carolina Department of Transportation (NCDOT), construction within jurisdictional areas
may proceed upon permit issuance; however, a copy of this form signed by NCDMS must be provided to the District
within 30 days of permit issuance. NCDOT remains fully responsible for the mitigation until the District has received this
form, confirming that the Sponsor has accepted responsibility for providing the mitigation requirements listed herein.
Signed copies of this document must be retained by the Permittee, Mitigation Sponsor, and in the USACE administrative
records for both the permit and the Bank/ILF Instrument. It is the Permittee’s responsibility to ensure that the District
Project Manager (address below) is provided with a signed copy of this form.
If changes are proposed to the type, amount, or location of mitigation after this form has been signed and returned to
the District, the Sponsor must obtain case-by-case approval from the District Project Manager and/or North Carolina
Interagency Review Team (NCIRT). If approved, higher mitigation ratios may be applied, as per current District guidance
and a new version of this form must be completed and included in the District administrative records for both the permit
and the Bank/ILF Instrument.

Comments/Additional Conditions:
To offset the 0.324 acre permanent impacts for the construction of the new WWTP, the applicant will purchase 0.7 credits
of Riparian wetlands from the Stone Farm Mitigation Bank. This is a Special condition for the permit, which was issued on
September 29, 2021.

This form is not valid unless signed below by the District Project Manager and by the Mitigation Sponsor on Page 1. Once
signed, the Sponsor should provide copies of this form along with an updated bank ledger to: 1) the Permittee, 2) the
District Project Manager at the address below, 3) the Bank Manager listed in RIBITS, and 4) the Wilmington District
Mitigation Office, 3331 Heritage Trade Drive, Suite 105, Wake Forest, NC 27587 (or by email to [e-mail]).
Questions regarding this form or any of the permit conditions may be directed to the District Mitigation Office.

USACE Project Manager: Gary H. Beecher
USACE Field Office: Wilmington Regulatory Field Office
US Army Corps of Engineers
69 Darlington Avenue
Wilmington, NC 28403
Email: [e-mail]

Ejhjubmmz!tjhofe!cz!Hbsz!I/!Cffdifs!

Hbsz!I/!Cffdifs
Ebuf;!3132/1:/3:!1:;25;61!.15(11(
September 29, 2021
Wilmington District Project Manager Signature Date of Signature
Current Wilmington District mitigation guidance, including information on mitigation ratios, functional assessments, and
mitigation bank location and availability, and credit classifications (including stream temperature and wetland groupings) is
.
available at http://ribits.usace.army.mil
Page 2 of 2

North Carolina
Brunswick County
_
^
Project Location
Legend
Project LOD (37.6 ac.)
Waters Survey Limit (505.5 ac.)
Vicinity Map
02,5005,000
Feet
Mublerry Branch Water Reclamation Facility
1 inch = 5,000 feet
Southport, Brunswick County, NC
µ

BYDESCRIPTIONDATENO.
OVERALL SITE PLAN - SHEET 1
DRAWING TITLE:
TCHSEGGCH2021
WASTEWATER TREATMENT AND DISPOSAL FOR THE CITY OF SOUTHPORT
C3
SUITE 300
704-334-5348
704-334-0078
(t)(f)
PROFESSIONAL SEAL
CHARLOTTE, NC 28208
NC LICENSE NO.F-0374
WWW.WKDICKSON.COM
20170253.00.WL
1213 W. MOREHEAD STREET
REVISION RECORDPROJECT NAME:
community infrastructure consultants
PROJ. MGR.:DESIGN BY:DRAWN BY:PROJ. DATE:DRAWING NUMBER:WKD PROJ. NO.:
FINAL DESIGN - NOT RELEASED FOR CONSTRUCTION
jo
pg
xfumboe/
bd/
jnqbdu
jotubmmbujpo
1/143
X3;ufnqpsbszTfxfsnbjoubjofe
pg
gps
jnqbdu
bd/
boe
nbjoufobodf
1/129
X2;qfsnbofouDmfbsjohdpowfstjpotfxfsdpssjeps
C4
pg
gps
jnqbdu
bd/
boe
nbjoufobodf
1/144
X4;qfsnbofouDmfbsjohdpowfstjpotfxfsdpssjeps
FOR CONTINUATION SEE SHEET
6/7/2021 11:38:58 AM, DKHAN, Z:\\Projects\\Environmental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_C_SHT_EXIST COND OVERALL.dwgFILE
PATH:
FROM THE ORIGINAL OF THIS DOCUMENT, MARKED WITH AN ORIGINAL SIGNATURE AND SEAL SHALL BE CONSIDERED TO BE VALID, TRUE COPIES.
DELETIONS TO THIS DOCUMENT, IN WHOLE OR IN PART, WITHOUT WRITTEN CONSENT OF W.K. DICKSON & CO., INC., IS PROHIBITED. ONLY COPIES

BYDESCRIPTIONDATENO.
OVERALL SITE PLAN - SHEET 2
DRAWING TITLE:
TCHSEGGCH2021
WASTEWATER TREATMENT AND DISPOSAL FOR THE CITY OF SOUTHPORT
C4
SUITE 300
704-334-5348
704-334-0078
(t)(f)
PROFESSIONAL SEAL
CHARLOTTE, NC 28208
NC LICENSE NO.F-0374
WWW.WKDICKSON.COM
20170253.00.WL
1213 W. MOREHEAD STREET
REVISION RECORDPROJECT NAME:
community infrastructure consultants
PROJ. MGR.:DESIGN BY:DRAWN BY:PROJ. DATE:DRAWING NUMBER:WKD PROJ. NO.:
FINAL DESIGN - NOT RELEASED FOR CONSTRUCTION
pg
spbe
jnqbdu
bd/
bddftt
bd/
1/1:6
tfxfs
gps
jnqbdu
pg
X5;qfsnbofouGjmm
fyjtujoh
pg
spbegppuqsjou
mg01/114
jo
jnqbdu
41
bd/
ufnqpsbsz
T2;pgJotubmmbujpomjoftdvmwfsu
bddftt
1/287
gps
X6;qfsnbofouGjmm
C3
pg
bd/
up
jnqbdutfxfs
spbe
mg01/118
dvmwfsu
27
T3;qfsnbofouJotubmmbujpoboetvqqpsudspttjoh
FOR CONTINUATION SEE SHEET
pg
gjfme
jnqbdu
bd/
tqsbz
1/113
gps
X7;qfsnbofouGjmm
6/7/2021 11:38:13 AM, DKHAN, Z:\\Projects\\Environmental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_C_SHT_EXIST COND OVERALL.dwgFILE
PATH:
FROM THE ORIGINAL OF THIS DOCUMENT, MARKED WITH AN ORIGINAL SIGNATURE AND SEAL SHALL BE CONSIDERED TO BE VALID, TRUE COPIES.
DELETIONS TO THIS DOCUMENT, IN WHOLE OR IN PART, WITHOUT WRITTEN CONSENT OF W.K. DICKSON & CO., INC., IS PROHIBITED. ONLY COPIES

BYDESCRIPTIONDATENO.
MULBERRY BRANCH CROSSING PLAN & PROFILE
DRAWING TITLE:
TCHTCHATM2020
WASTEWATER TREATMENT AND DISPOSAL FOR THE CITY OF SOUTHPORT
SUITE 300
704-334-5348704-334-0078
C57
(t)(f)
PROFESSIONAL SEAL
CHARLOTTE, NC 28208
NC LICENSE NO.F-0374
WWW.WKDICKSON.COM
20170253.00.WL
1213 W. MOREHEAD STREET
REVISION RECORDPROJECT NAME:
community infrastructure consultants
PROJ. MGR.:DESIGN BY:DRAWN BY:PROJ. DATE:DRAWING NUMBER:WKD PROJ. NO.:
FINAL DESIGN - NOT RELEASED FOR CONSTRUCTION
R
Y
-
0
0
1
R
Y
-
0
0
1
R
Y
-
0
0
1
H
C
N
A
R
R
B
Y
-
Y
0
0
R
1
R
E
B
L
U
M
R
Y
-
0
0
1
R
Y
-
0
0
1
0
5
+
3
R
Y
-
0
0
1
SEE PROJECT SPECIFICATIONS FOR DESCRIPTION OF SUITABLE BACKFILLMATERIAL AND COMPACTION REQUIREMENTS. CONTRACTOR SHALLPROVIDE SUITABLE MATERIAL AS NECESSARY TO ACHIEVE FINAL PROJECTGRADES.CONTRACTOR
TO ENSURE POSITIVE DRAINAGE.SEE SHEET D2 FOR SITE DETAILS.SEE SHEET D4 FOR HEADWALL DETAILS.CONTRACTOR SHALL PROVIDE N.C. PROFESSIONAL ENGINEER SEALEDSHOP DRAWINGS OF HEADWALL, CULVERT,
AND CULVERT FOUNDATIONDETAILS FROM PIPE MANUFACTURER AND SUBMIT TO ENGINEER FORREVIEW. CULVERT SHALL BE HL-93 LOAD RATED.PLEASE REFER TO THE GEOTECHNICAL ENGINEERING REPORT PREPAREDBY
ECS SOUTHEAST, LLP DATED FEBRUARY18, 2019 (ECS PROJECT NUMBER22:27032R1) FOR ALL SUBSURFACE RECOMMENDATIONS.
2.3.4.5.6.
NOTES:1.
0
0
+
3
WETLANDS
4440
363230
WETLANDS
2+50
TO SPRAY AREAS
PROPOSED PVC FM
TO INFILTRATION BASINS
PROPOSED PVCEFFLUENT FM
ALUMINUM STRUCTURAL PLATE
HEADWALL 2, SEE SHEET D4 FORHEADWALL DETAILS
C19
STAKES, AND RIPARIANSEEDING REQUIRED TOSEE SHEET D4 FOR DETAILS
COIR FIBER MATTING, LIVEGRADING LIMITS AS HATCHED,
PROPOSED EFFLUENT FMTO SPRAY AREA
R
PROPOSED EFFLUENT FMTO INFILTRATION BASINS
Y
-
0
R
0
1
Y
-
ACCESS ROAD,SEE SHEET
PROPOSED 12' GRAVEL
0 M
0
0 F
F
M
1 F
M 0
+
F
M
RYRALUMINUM STRUCTURAL
-0PLATE HEADWALL 2
01
Y F
M
-2
0
RY-
00
10
1
20'-1" SPAN X 6'-6" RISEALUMINUM STRUCTURAL PLATE
PROPOSED 16 LFBOX CULVERT
F
2
M
M 20'-1" SPAN X 6'-6" RISEALUMINUM STRUCTURAL PLATEBOX CULVERT @ 0.00%
RPROPOSED 16 LF
F
FMFMFM M
F PROPOSEDGRADE 2+00
Y
F-
M
0
FMFMFM 0
4
0
1
INV: 33.00
R
Y
-
0
0
1
TOP: 40.25
2
R
Y
-
0
0STA. 1+86.78
1
F
M
F
M
FMFM
PROP. HEADWALL 2
R
R
F
Y M
Y
-
-0
0
1
0
0
0-YR
10
-YR1
100
INV: 33.00
YR
00-
1
R
00-Y
1R
Y
-
0TOP: 40.25
1
0
1
STA. 1+70.78
RACCESS ROAD CL
Y
-
0
0
0 1
0
+
9
5
PROP. HEADWALL 1
R
Y
-
00
1
R
Y-
0
0
1
R
Y-
0
0
1
R
Y
-
0
0
0
+
8
0 5
R SCALE: HOR 1"=20'; VERT 1"=2'
Y1
-
0
0
1
R
Y
-
0
0
pg
1
R
Y
-
0
bd/0
1
PLAIN, TYP.
IN-SITU BED MATERIAL
up
jnqbdutfxfs
R
100-YR FLOOD
YPLATE HEADWALL 1
-
R
spbe
0
BURY ONE FOOT, FILL WITH
Y0
mg01/118
-
1
0
0
1
dvmwfsu
27
ALUMINUM STRUCTURAL
GRADE
C-MULBERRY BRANCH CULVERT
0
EXISTING
0
T3;qfsnbofouJotubmmbujpoboetvqqpsudspttjoh
+
1
FOR HEADWALL DETAILS
R
Y
-
0
0
HEADWALL 1, SEE SHEET D4
R1
Y
-
0
ALUMINUM STRUCTURAL PLATE
0
1
R
Y 1+00
-
0
4440363230
0
1
R
Y
-
0
0
1
R
Y
-
R
0
0
1Y
-
0
0
1
R
WETLANDS
Y
-
0
0
1
R
Y
-
0
0
1
WETLANDS
R
Y
-
0
0
1
R
0
Y
-
0
0
0
+
1
0
R
Y
-
0
0
1
R
Y
-
0
0
1
R
Y
-
0
0
1
MULBERRY BRANCH
Dspttjoh
R
Y
-
0
R
0Y
-
0
0
1
1
40
WETLAND LIMITS
Tusfbn R
Y
-
0
0
R
1
Y
-
0
0
1
20
Csbodi
R
Y
-
0
0
R
1
Y
-
0
0
0
1
VERT. SCALE: 1" = 2'
HORIZ. SCALE: 1" = 20'
EX. SOIL PATH, TYP.
R
Nvmcfssz
Y
-
0
0
R
1
Y
-
20
0
0
1
R
Y
-
5/17/2021 2:49:48 PM, CHAIGLER, Z:\\Projects\\Environmental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_C_SHT_MULBERRY BRANCH CROSSING.dwgFILE
PATH:
0
0
1
FROM THE ORIGINAL OF THIS DOCUMENT, MARKED WITH AN ORIGINAL SIGNATURE AND SEAL SHALL BE CONSIDERED TO BE VALID, TRUE COPIES.
DELETIONS TO THIS DOCUMENT, IN WHOLE OR IN PART, WITHOUT WRITTEN CONSENT OF W.K. DICKSON & CO., INC., IS PROHIBITED. ONLY COPIES

BYDESCRIPTIONDATENO.
HEADWALL DETAIL
DRAWING TITLE:
TCHTCHATM2020
WASTEWATER TREATMENT AND DISPOSAL FOR THE CITY OF SOUTHPORT
D4
SUITE 300
704-334-5348704-334-0078
(t)(f)
PROFESSIONAL SEAL
CHARLOTTE, NC 28208
NC LICENSE NO.F-0374
WWW.WKDICKSON.COM
20170253.00.WL
1213 W. MOREHEAD STREET
REVISION RECORDPROJECT NAME:
community infrastructure consultants
PROJ. MGR.:DESIGN BY:DRAWN BY:PROJ. DATE:DRAWING NUMBER:WKD PROJ. NO.:
FINAL DESIGN - NOT RELEASED FOR CONSTRUCTION
INV = 33.00BOT. = 30.75
TOP = 40.25
NOT TO SCALE
9'
RIPARIAN SEEDING SCHEDULE
FOR PROPOSED GRADING AND INVERT ELEVATIONS.
C57
CONTRACTOR SHALL PROVIDE N.C. PROFESSIONAL ENGINEER SEALED SHOP DRAWINGS OFAND SUBMIT TO ENGINEER FOR REVIEW. CULVERT SHALL BE HL-93 LOAD RATED.SOUTHEAST, LLP DATED FEBRUARY18, 2019
(ECS PROJECT NUMBER 22:27032R1) FOR ALLSUBSURFACE RECOMMENDATIONS.STRUCTURAL ALUMINUM PLATE BOX CULVERT SHALL HAVE A MINIMUM STRUCTURALOPENING OF 109.2 SQUARE FEET.
DETAIL SHOWN FOR REPRESENTATIONAL PURPOSES ONLY.HEADWALL, CULVERT, AND CULVERT FOUNDATION DETAILS FROM PIPE MANUFACTURERREFERENCE SHEET PLEASE REFER TO THE GEOTECHNICAL ENGINEERING REPORT
PREPARED BY ECS
2.3.4.5.
1.
NOTES:
20%40%20%20%
Percent
THIS SHEET.
5'
Common Name Silky DogwoodBlackWillowSilky WillowCottonwood
LIVE STAKE DETAIL
3'
THE ORDINARY HIGH WATER MARK AND EXTEND PAST NEWLYGRADED TOP OF BANK A MINIMUM OF 24".STREAMBANK AND WETLAND AREAS SHALL BE SEEDED PER THE
LINE ALL DISTURBED CHANNEL BANKS WITH COIR FIBERMATTING.MATTING SHOULD BEGIN INSIDE THE CHANNEL AT OR BELOWPLACE LIVE STAKES IN MATTING MATERIAL IN AREADESIGNATED ON THIS SHEET.RIPARIAN
SEEDING SCHEDULE ON
2.4.
NOTES1.3.
BURY ONE FOOT, FILL WITHIN-SITU BED MATERIAL
LIVE STAKE SCHEDULE
Salix nigraSalix sericeaPopulus deltoides
Scientific Name Cornus amomum NOT TO SCALE
COIR FIBERMATTING
LIVE STAKE PLANTINGS DETAIL
THE STAKES SHOULD HAVE A
DETAILLIVE STAKES SHOULD BE 2-3FEET LONG. ADDITIONALLY,DIAMETER OF 0.75 TO 2INCHES.
COIR FIBERMATTING
MIN 4'
MIN 18"
24'
0.5' TO 1.5'
20' - 1" SPAN
45 DEGREE TAPERED BUTT END
NOT TO SCALE
CHANNEL INV = 34.00
CULVERT WITH FULL INVERT
HEADWALL H1 DETAIL
MIN. CROSS SECTIONAL AREA = 109.2 SQ FT
#50 (20'-1" SPAN X 6'-6" RISE) ALUMINUM BOX
0.75" TO 2"
LATERAL BUD
AT SLIGHT ANGLE
ONCE INSTALLED TOP
SIDE BRANCH REMOVED
SHALL BE CUT AT AN ANGLE
STRUCTURAL PLATE HEADWALL
FULLY WELDED ALUMINUM
NOT TO SCALE
Dsptt.
STRETCH TIGHT.
COIR FIBER MATTING
DO NOT
THICKNESS - 0.35 IN. MINIMUM.WEIGHT - 29 OZ/SYOPEN AREA - 38%
100 % COCONUT FIBER (COIR) TWINE WOVEN INTO AHIGH STRENGTH MATRIX.FLOW VELOCITY- OBSERVED 16 FT/SEC
9'
COIR FIBER MATTING MUST MEET OR EXCEED THEFOLLOWING REQUIREMENTS:
Dvmwfsu
8'
Csbodi
Nvmcfssztfdujpo
0.5'SITE PREPARATIONTEST SOILS FOR ANY NUTRIENT DEFICIENCIES AND SUBMIT SOIL TEST RESULTS TO THE ENGINEER. APPLY ANY TREATMENT SUCH AS LIME OR FERTILIZERSTO THE SOIL IF NEEDED.SEEDINGSEE
THIS SHEET FOR SEEDING REQUIREMENTS. APPLY SEED TO SOIL BEFORE PLACING MATTING.SEE GRADING NOTES ON PLAN AND PROFILE SHEETS AND DETAIL SHEETS FOR INFORMATION REGARDING WHAT AREAS ARE
TO RECEIVE COIR MATTING.OVERLAP ADJACENT MATS 3" (IN DIRECTION PARALLEL TO FLOW) AND ANCHOR EVERY 12" ACROSS THE OVERLAP. THE UPSTREAM MAT SHOULD BE PLACEDOVER THE DOWNSTREAM MAT.ANCHOR
MAT USING BIODEGRADABLE STAKES OR PINS.TRENCH, AND COMPACT SOIL.STAPLE AT 12" INTERVALS ALONG OVERLAP.STREAM BANK MATTING TO BE INSTALLED FROM TOE OF BANK TO A MINIMUM OF 2.0' PAST
TOP OF BANK. SEE FIGURE 3 FOR TERMINATION AT TOP OF
INSTALLATION NOTES:GRADE AND COMPACT AREA.REMOVE ALL ROCKS, CLODS, VEGETATION, AND OBSTRUCTIONS SO THAT MATTING WILL HAVE DIRECT CONTACT WITH THE SOIL.PREPARE SEEDBED BY LOOSENING 3
TO 4 INCHES OF TOPSOIL ABOVE FINAL GRADE.INSTALLATION - STREAM BANKEDGES SHOULD BE SHINGLED AWAY FROM THE FLOW OF WATER.LAY MAT LOOSE TO ALLOW CONTACT WITH SOIL. CUT 8" x 8" TRENCH
ALONG TOP OF BANK FOR MAT TERMINATION AS SHOWN IN FIGURES 1 & 2. EXTEND MAT 2 TO 3 FEET PAST TOP OF BANK.PLACE ADJACENT ROLLS IN THE ANCHOR TRENCH WITH A MINIMUM OF 4" OVERLAP. SECURE
WITH BIODEGRADABLE STAKES OR PINES, BACKFILL ANCHORBANK.IF MORE THAN ROLL IS REQUIRED TO COVER THE CHANNEL FROM THE TOP OF BANK DOWN TO THE TOE, THEN OVERLAP MATTING BY A MINIMUM OF
1'.
5/17/2021 2:56:58 PM, CHAIGLER, Z:\\Projects\\Environmental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_C_SHT_MULBERRY BRANCH CROSSING.dwgFILE
PATH:
FROM THE ORIGINAL OF THIS DOCUMENT, MARKED WITH AN ORIGINAL SIGNATURE AND SEAL SHALL BE CONSIDERED TO BE VALID, TRUE COPIES.
DELETIONS TO THIS DOCUMENT, IN WHOLE OR IN PART, WITHOUT WRITTEN CONSENT OF W.K. DICKSON & CO., INC., IS PROHIBITED. ONLY COPIES

BYDESCRIPTIONDATENO.
EROSION CONTROL AND PLANTING NOTES
DRAWING TITLE:
TCHJWH / RETCH / NS2020
WASTEWATER TREATMENT AND DISPOSAL FOR THE CITY OF SOUTHPORT
SUITE 300
704-334-5348704-334-0078
D11
(t)(f)
PROFESSIONAL SEAL
CHARLOTTE, NC 28208
NC LICENSE NO.F-0374
WWW.WKDICKSON.COM
20170253.00.WL
1213 W. MOREHEAD STREET
REVISION RECORDPROJECT NAME:
community infrastructure consultants
PROJ. MGR.:DESIGN BY:DRAWN BY:PROJ. DATE:DRAWING NUMBER:WKD PROJ. NO.:
FINAL DESIGN - NOT RELEASED FOR CONSTRUCTION
5/17/2021 2:57:38 PM, CHAIGLER, Z:\\Projects\\Environmental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_C_SHT_CIVIL DETAILS.dwgFILE
PATH:
FROM THE ORIGINAL OF THIS DOCUMENT, MARKED WITH AN ORIGINAL SIGNATURE AND SEAL SHALL BE CONSIDERED TO BE VALID, TRUE COPIES.
DELETIONS TO THIS DOCUMENT, IN WHOLE OR IN PART, WITHOUT WRITTEN CONSENT OF W.K. DICKSON & CO., INC., IS PROHIBITED. ONLY COPIES

(ac.)
0.324
160.007
(lf)Area
Impacts:
Wetland
Impacts:
Stream
Permanent
Total
Permanent
(Permanent/Temporary)Length
Total
PermanentN/A0.095PermanentN/A0.176
FieldPermanentN/A0.002
Spray
for
RoadRoad
InsallationTemporary300.003InstallationTemporaryN/A0.032
CrossingPermanent160.007
e
Tabl
Impact
WWTP
Impacts
Impacts
NumberActivityType
SouthportStreamImpactS1SewerS2RoadWetlandW1ConversionPermanentN/A0.018W2SewerW3ConversionPermanentN/A0.033W4AccessW5AccessW6Grading

BYDESCRIPTIONDATENO.
1
SEGADDED MANUAL SCREEN BYPASS CHANNEL10/2021
HEADWORKS - PLAN (BELOW GRATING)
DRAWING TITLE:
TCHSEGGCH2021
WASTEWATER TREATMENT AND DISPOSAL FOR THE CITY OF SOUTHPORT
SUITE 300 M2
704-334-5348
704-334-0078
(t)(f)
PROFESSIONAL SEAL
CHARLOTTE, NC 28208
NC LICENSE NO.F-0374
WWW.WKDICKSON.COM
20170253.00.WL
1213 W. MOREHEAD STREET
REVISION RECORDPROJECT NAME:
community infrastructure consultants
PROJ. MGR.:DESIGN BY:DRAWN BY:PROJ. DATE:DRAWING NUMBER:WKD PROJ. NO.:
FINAL DESIGN - NOT RELEASED FOR CONSTRUCTION
FLOW
FLOW
FLOW
FLOW
HEADWORKS - PLAN (ELEV 58.0')
FLOW
FLOW
FLOW
FLOW
FLOW
10/4/2021 8:35:16 AM, SGERLACH, Z:\\Projects\\Environmental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_M_SHT_HEADWORKS.dwgZ:\\Projects\\Environm
ental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_M_SHT_HEADWORKS.dwgFILE PATH:
FROM THE ORIGINAL OF THIS DOCUMENT, MARKED WITH AN ORIGINAL SIGNATURE AND SEAL SHALL BE CONSIDERED TO BE VALID, TRUE COPIES.
DELETIONS TO THIS DOCUMENT, IN WHOLE OR IN PART, WITHOUT WRITTEN CONSENT OF W.K. DICKSON & CO., INC., IS PROHIBITED. ONLY COPIES

BYDESCRIPTIONDATENO.
SEGADDED MONITORING WELL IDENTIFICATION REQUREMENTS10/4/20211
UTILITY DETAILS
DRAWING TITLE:
TCHSEGGCH2021
WASTEWATER TREATMENT AND DISPOSAL FOR THE CITY OF SOUTHPORT
D7
SUITE 300
704-334-5348
704-334-0078
(t)(f)
PROFESSIONAL SEAL
CHARLOTTE, NC 28208
NC LICENSE NO.F-0374
WWW.WKDICKSON.COM
20170253.00.WL
1213 W. MOREHEAD STREET
REVISION RECORDPROJECT NAME:
community infrastructure consultants
PROJ. MGR.:DESIGN BY:DRAWN BY:PROJ. DATE:DRAWING NUMBER:WKD PROJ. NO.:
FINAL DESIGN - NOT RELEASED FOR CONSTRUCTION
10/4/2021 8:28:24 AM, SGERLACH, Z:\\Projects\\Environmental\\Brunswick County\\2017025300WL - Southport Wastewater Study and Design\\CADD\\Plan Set\\20170253_C_SHT_CIVIL DETAILS.dwgFILE
PATH:
FROM THE ORIGINAL OF THIS DOCUMENT, MARKED WITH AN ORIGINAL SIGNATURE AND SEAL SHALL BE CONSIDERED TO BE VALID, TRUE COPIES.
DELETIONS TO THIS DOCUMENT, IN WHOLE OR IN PART, WITHOUT WRITTEN CONSENT OF W.K. DICKSON & CO., INC., IS PROHIBITED. ONLY COPIES

that the
Contractor fails to complete the work indicated

DesignCalculations
WastewaterTreatmentandDisposalfortheCityofSouthport
WKDProjectNumber:20170253.00.WL
For
BrunswickCounty

I.NPDESPermitLimits
II.DesignFlowRates

III.Headworks

IV.InfluentPumpStation

V.EqualizationTank

VI.OxidationDitch

ͲЋЉ
¬

N
N,Max
N
O2
1
N,Max
N
C,Min
d
C,Design
N,design
N
0
0
BOD
D
H

Req
Des
C
SF
C,SF

VII.SecondaryClarifiers

VIII.DiscFilters
IX.UVDisinfection

X.PumpStation3:EffluentPumpStationtoHighRateInfiltrationBasins

XI.PumpStation4:RAS/WASPumpStation

XII.AerobicDigesters

2,040lbs/day(Total)
ConverttoAir
582cfmtotal

XIII.PumpStation5:SludgeTransferPumpStation
XIV.ProposedIrrigationSprayField

XV.HighRateInfiltrationBasins

XVI.PumpStation6:SiteDrainPumpStation
XVII.PumpStation7:SiteScumPumpStation
XVIII.Bouyancy

-«º#µ½´¬µ¸©«

-«º#µ½´¬µ¸©«

-«º#µ½´¬µ¸©«

(LBS)
DOWN
NET
FORCE
(LBS)
CONCRETE
FORCE
(LBS)
BOUYANT
FORCE
(CF)
TOP
VOLUME
(CF)
BASE
VOLUME
(CF)
WALL
CONC.
VOLUME
(CF)
SUBMERGED
VOLUME
(FT)
(FT)BASE
MHRIM

-«º#µ½´¬µ¸©«

-«º#µ½´¬µ¸©«

Narrative
FlowConditions
Summary

HydraulicCalculations
ScreenChannelUpstream
WaterLevel
54.86ft55.33ft
ADF
WaterLevel
55.47ft56.12ft
Peak
ScreenChannelDownstream
WaterLevel
53.86ft54.33ft
ADF
WaterLevel
54.47ft55.12ft
Peak
ChannelintoGritSystem
WaterLevel
50.77ft51.76ft
ADF
WaterLevel
51.84ft51.97ft
Peak
GritSystem
WaterLevel
50.69ft50.76ft
ADF
WaterLevel
50.84ft50.97ft
Peak

GritBypassChannel
WaterLevel
50.70ft51.00ft
ADF
WaterLevel
50.87ft51.44ft
Peak

HeadworksEffluentChannel
WaterLevel
48.69ft48.96ft
ADF
WaterLevel
48.83ft49.35ft
Peak

Narrative
FlowConditions
Summary

HydraulicProfileCalculations
74.63ft74.83ft
HydraulicGrade72.60ft73.13ft
HydraulicGrade72.57ft72.63ft

HydraulicGrade63.29ft68.46ft
HydraulicGrade63.25ft67.95ft

HydraulicGrade57.28ft58.15ft
HydraulicGrade57.16ft57.22ft

HydraulicGrade52.04ft52.16ft

Narrative
SystemConditions
PumpInfo
GritPumpStationSystemHead
40
35
30
(ft.)
25
(%)
Head
20
15
Dynamic
Efficiency
10
Total
5
0
FlowRate(GPM)

Scenario1NewLevelPipeSystemHeadCharacteristics
Scenario1NewLevelPipeDutyPoint(s)
Q(gpm)HfHmHfHmTDH
Scenario1NewLevelPipeSystemHead
Q(gpm)HfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristics
Scenario2OldPipeDutyPoint(s)
Q(gpm)HfHmHfHmTDH
Scenario2OldPipeSystemHead
Q(gpm)HfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
InfluentPumpStationtoAnaerobicSelectorSystemHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicswithOnePumpinOperation
SuctionDischarge
Scenario1NewPipeDutyPoint(s)withOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadwithOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithTwoPumpsinOperation
SuctionDischarge
Scenario2OldPipeDutyPoint(s)withTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
InfluentPumpStationtoLagoonSystemHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicswithOnePumpinOperation
SuctionDischarge
Scenario1NewPipeDutyPoint(s)withOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadwithOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithTwoPumpsinOperation
SuctionDischarge
Scenario2OldPipeDutyPoint(s)withTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
InfluentPumpStationtoEQTankHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicswithOnePumpinOperation
SuctionDischarge
Scenario1NewPipeDutyPoint(s)withOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadwithOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithTwoPumpsinOperation
SuctionDischarge
Scenario2OldPipeDutyPoint(s)withTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
RASPumpStationSystemHead
60
50
(ft.)
40
Head
30
Dynamic
20
Total
10
0
FlowRate(GPM)

NewPipeSystemHeadCharacteristics
SuctionDischarge
NewPipeDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
NewPipeSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

OldPipeSystemHeadCharacteristics
SuctionDischarge
OldPipeDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
OldPipeSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
RASPumpStationSystemHead
60
50
(ft.)
40
Head
30
Dynamic
20
Total
10
0
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicsNoRecycleOn
SuctionDischarge
Scenario1NewPipeDutyPoint(s)NoRecycleOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadNoRecycleOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Scnario2OldPipeSystemHeadCharacteristicsRecycleOn
SuctionDischarge
Scnario2OldPipeDutyPoint(s)RecycleOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scnario2OldPipeSystemHeadRecycleOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
WASPumpStationSystemHead
60
100
90
50
80
(ft.)
70
40
60
(%)
Head
30
50
40
Dynamic
Efficiency
20
30
Total
20
10
10
0
0
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicswithScumPumpsOff
SuctionDischarge
Scenario1NewPipeDutyPoint(s)withScumPumpsOff
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadwithScumPumpsOff
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithRAS1.0ADF,
1ClarifierOnline,ScumPumpsOn
SuctionDischarge
Scenario2OldPipeDutyPoint(s)withRAS1.0ADF,1ClarifierOnline,ScumPumpsOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithRAS1.0ADF,1ClarifierOnline,ScumPumpsOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
WASPumpStationSystemHead
120
100
(ft.)
80
(%)
Head
60
Dynamic
Efficiency
40
Total
20
0
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicswithScumPumpsOff
SuctionDischarge
Scenario1NewPipeDutyPoint(s)withScumPumpsOff
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadwithScumPumpsOff
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithRAS1.0ADF,
DrainPSon,EffluentPSon
SuctionDischarge
Scenario2OldPipeDutyPoint(s)withRAS1.0ADF,1ClarifierOnline,ScumPumpsOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithRAS1.0ADF,1ClarifierOnline,DrainPSon
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
EffluentPumptoInfiltrationBasinSystemHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicswithOnePumpinOperation
SuctionDischarge
Scenario1NewPipeDutyPoint(s)withOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadwithOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithTwoPumpsinOperation
SuctionDischarge
Scenario2OldPipeDutyPoint(s)withTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithTwoPumpsinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
EffluentPumptoInfiltrationBasinSystemHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicswithOnePumpinOperation
SuctionDischarge
Scenario1NewPipeDutyPoint(s)withOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadwithOnePumpinOperation
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithDrainandWASPumpsOn
SuctionDischarge
Scenario2OldPipeDutyPoint(s)withDrainandWASPumpsOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithTwoPumpsinOperationWASPumpsOn
SuctionDischarge
Q(gpm)HfHmHfHmHfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
DrainPumpStationSystemHead
(ft.)
(%)
Head
Efficiency
Dynamic
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristics
SuctionDischarge
Scenario1NewPipeDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH
Scenario1NewPipeSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristics
SuctionDischarge
Scenario2OldPipeDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH
Scenario2OldPipeSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
DrainPumpStationSystemHead
(ft.)
(%)
Head
Efficiency
Dynamic
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristics
SuctionDischarge
Scenario1NewPipeDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH
Scenario1NewPipeSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristics
SuctionDischarge
Scenario2OldPipeDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH
Scenario2OldPipeSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
ScumPumpStationSystemHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicsWASPumpsOff
Scenario1NewPipeDutyPoint(s)WASPumpsOff
Q(gpm)HfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadWASPumpsOff
Q(gpm)HfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithoneWASPumpOn
Scenario1OldPipeDutyPoint(s)withoneWASPumpOn
Q(gpm)HfHmHfHmHfHmTDH
Scenario1OldPipeSystemHeadwithoneWASPumpOn
Q(gpm)HfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
ScumPumpStationSystemHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

Scenario1NewPipeSystemHeadCharacteristicsWASPumpsOff
Scenario1NewPipeDutyPoint(s)WASPumpsOff
Q(gpm)HfHmHfHmHfHmTDH
Scenario1NewPipeSystemHeadWASPumpsOff
Q(gpm)HfHmHfHmHfHmTDH

Scenario2OldPipeSystemHeadCharacteristicswithoneWASPumpOn
Scenario2OldPipeDutyPoint(s)withoneWASPumpOn
Q(gpm)HfHmHfHmHfHmTDH
Scenario2OldPipeSystemHeadwithoneWASPumpOn
Q(gpm)HfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
TransferPSSystemHead
(ft.)
(%)
Head
Dynamic
Efficiency
Total
FlowRate(GPM)

NewPipeFullDigesterSystemHeadCharacteristics
SuctionDischarge
NewPipeFullDigesterDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmTDH
NewPipeFullDigesterSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmTDH

OldPipeEmptyDigesterSystemHeadCharacteristics
SuctionDischarge
OldPipeEmptyDigesterDutyPoint(s)
SuctionDischarge
Q(gpm)HfHmHfHmTDH
OldPipeEmptyDigesterSystemHead
SuctionDischarge
Q(gpm)HfHmHfHmTDH

2¯º«"®§¸§©º«¸¯¹º¯©¹
2¶¸¯´±²«¸"®§¸§©º«¸¯¹º¯©¹
2¿¹º«³"§²©»²§º¯µ´¹

PSI
Loss,
FtTotal
System
Loss,
Irrigation
for
LossTotal
Pump
of
PSI
LossMinor
Discharge
Resultant
ValueFriction
ValueK
C
fed
Branch
by
Sprinklers
Narrative:
DescriptionDiameterLengthMaterialFlowVelocity
Assumptions:Calculations:Pipe

02004006008001,0001,200
0
80604020
180160140120100

System
NPW
for
Pump
of
PSI
Discharge
Recommended
Narrative:
Description
SystemCalculations

Narrative
SystemConditions
PumpInfo
EqualizationBasinJetAerationStationSystemHead
86
84
82
(ft.)
80
(%)
Head
78
Dynamic
Efficiency
76
Total
74
72
70
FlowRate(GPM)

NewPipeSystemHeadCharacteristics
NewPipeDutyPoint(s)
Q(gpm)HfHmHfHmTDH
NewPipeSystemHead
Q(gpm)HfHmHfHmTDH

OldPipeSystemHeadCharacteristics
OldPipeDutyPoint(s)
Q(gpm)HfHmHfHmTDH
OldPipeSystemHead
Q(gpm)HfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
Ox.DitchJetAerationStationSystemHead
(ft.)
Head
Dynamic
Total
FlowRate(GPM)

NewPipeSystemHeadCharacteristics
NewPipeDutyPoint(s)
Q(gpm)HfHmHfHmHfHmTDH
NewPipeSystemHead
Q(gpm)HfHmHfHmHfHmTDH

OldPipeSystemHeadCharacteristics
OldPipeDutyPoint(s)
Q(gpm)HfHmHfHmHfHmTDH
OldPipeSystemHead
Q(gpm)HfHmHfHmHfHmTDH

Narrative
SystemConditions
PumpInfo
DigesterJetAerationStationSystemHead
90
80
70
(ft.)
60
Head
50
40
Dynamic
30
Total
20
10
0
FlowRate(GPM)

NewPipeSystemHeadCharacteristics
NewPipeDutyPoint(s)
Q(gpm)HfHmHfHmTDH
NewPipeSystemHeadWASPumps
Q(gpm)HfHmHfHmTDH

OldPipeSystemHeadCharacteristics
OldPipeDutyPoint(s)
Q(gpm)HfHmHfHmTDH
OldPipeSystemHead
Q(gpm)HfHmHfHmTDH

Narrative
DesignCriteria
Calculations
Eq.LengthTotalPressureDropPressure
SegmentLengthDiameterAirflow
ofFittingsLengthPer100FtDrop
RecommendedMin.PSIPSI
8

Narrative
DesignCriteria
Calculations
Eq.LengthTotalPressureDropPressure
SegmentLengthDiameterAirflow
ofFittingsLengthPer100FtDrop
RecommendedMin.PSIPSI
8

Narrative
DesignCriteria
Calculations
Eq.LengthTotalPressureDropPressure
SegmentLengthDiameterAirflow
ofFittingsLengthPer100FtDrop
RecommendedMin.PSIPSI
8

Spreader
Level
at
Line
Pipe)
Manhole
Grade
(Full
(D/4)
in
Elevation
Area
Roughness
Radiuspipe
Hydraulic
PermiterSurface
of
Elevation
Sectional
of
Diameter
=Cross
=Wetted=Hydraulic=Water=Ground
)
2
(ft)
(ft)
(ft)(ft)
(in)=Pipe
(ft
(ft/ft)=Slope
(ft)=Length
H
w12
ALh
n=Manning'sDPRhS
Calculation
Length
cfs)cfs)
modelmodel
/s)/s)
33
A 2.02 A 2.21
1.400.79
(ft(ft
Spreader
CAPACITYCAPACITY
(i.e.(i.e.
Design
**
**
Spreader
Spreader
hydraulichydraulic
and
Level 1/21/2
grass/thicket/shrubs)grass/thicket/shrubs)
CapacityCapacity
SS
0.030.06
Level
Level
capacitycapacity
pipepipe
to
**
*(For*(For
SUFFICIENTSUFFICIENT
and Study
to
fullfull
pipepipe
Andrews'Andrews'
2/32/3
Drain
RequiredRequired
HH
feet*feet*
EdEd
full Drain full
0.480.40
RR
B
PVCPVC
D/4D/4
C
A
forfor
**
ForAssumesi.e.From=30 ForAssumesi.e.From=30
Capacity isis
Wastewater
Outfall
21
Outfall
Pipe
of
lengthlength
of
114.31114.31
1.486/n*1.486/n*
May
LengthLength
=0.013=1.396=4.19=51.14=50.80=1.26===0.013=0.785=3.14=51.65=50.00=0.62==
=0.333=490=0.250=430
Southport20170253.00.WL4DKTCH
Capacity
Outfall
spreaderspreader
By:
By:
No.
Capacity
Date:
/s)/s)
Name:
SpreaderSpreader
33
LevelLevel
(ft(ft
2.022.21
Basin
))
Project
22
QQ
Checked
LevelLevel
(ft)(ft)
(ft)(ft)
(ft)(ft)(ft)(ft)
(in)=16(in)=12
(ft(ft
(ft/ft)=0.001(ft/ft)=0.004
Computed(ft)(ft)
Project
HH
w12w12
HRI
nDAPRLhhS*Note:nDAPRLhhS*Note:

Equations
ȁ
ΐΏȁΓΓ
ΐȁΓΘ
ȝ

ȁȁ
Α
KValuesMinorLossesCoefficientforSystemHeadandHydraulicProfileDevelopment
Source
ValveProposed123456

ResidualsManagementPlan
BrunswickCounty
ShallotteWWTP
(º«³#«¹©¸¯¶º¯µ´
1.SummaryofResidualsManagementPlan
2.ResidualWasteDisposal
3.EstimatedQuantitiesofResidualWasteProduction
4.Discussion

ResidualsManagementPlan
1.SummaryofResidualManagementPlan
TheexistingShallotteWWTPwillcontinuetooperateunderthepermittedcapacityof0.50
MGD.InfluentflowtotheproposedShallotteWWTPwillconsistofflowfromexisting
ShallotteCollectionsystemforcemainsandfromcontrolledinfluentforcemainfromthe
Regional24inchtransmissionmain.ThisResidualManagementPlanisforthe
modificationstotheShallotteWWTP.
UnitprocesseswithintheproposedShallotteWWTPthatwillcaptureresidualsolidsfor
disposalarescreeningsandgritthatwillbedisposedofvialandfillandsettledsludge
withinthelagoonsthatwillbedredged,dewatered,anddisposedofvialandapplication.
2.ResidualWasteProduction
WastewaterthatenterstheShallotteWWTPwillflowintotheheadworksthatconsistsof
arotarydrumscreen,wheresolidswillbecapturedandconveyedtoadumpsterandthen
agritchamber,whereparticulatemattersuchassandandstoneswillsettleout.The
settledgritwillalsobeconveyedtoadumpsterfordisposal.Residualsremovedatthe
headworkswillbedisposedofinalandfill.
Afterwastewateristreatedintheheadworks,itispumpedtothelagoonsfortreatment,
followedbydisinfectionandlandapplicationandtransferredtotheproposedMulberry
BranchWaterReclamationFacility.
TheShallotteWWTPlagoonsarebeingmodifiedaspartofthisprojecttochangetheir
layoutfromparalleltoseries.Thismodificationwillpromoteimprovedsettlingof
suspendedsolidsduetoincreasedlengthofflowtravel.
Currently,theexistingShallotteWWTPisperiodicallydredged,andsolidsareremoved
fromthebottomsoflagoons.TheinfluentforcemaintothisWWTPandpumpscanbe
shutofforthrottledtoallowforfullcleaningofthelagoonsifneeded,althoughthe
operatingstaffcancurrentlycleaneachlagoonwithouttakingthemoutofservice.The
resultingdredgedsolidsisdewateredandhauledawayfordisposalthroughland
application.Theproposedprojectshouldnotincreasethequantityofsolidsproduced
withinthistreatmentplant.

3.EstimatedQuantitiesofResidualProduction
AccordingtoMetcalfandEddytheamountofscreeningsanticipatedfromaRotary
3
Drumtypescreenwithopeningsof6.25mmisbetween48ftpermilliongallonsof
wastewater.Basedonpermittedflowforoneyearthatwouldyield2245gallonsper
dayor8,00016,430gallonsperyearofscreenings.
Next,thesolidsgeneratedinthebiologicaltreatmentprocessisdeterminedasfollows:
Assumptions
DesignFlow500,000gpd(0.50MGD)
TotalLagoonVol.32,000,000gal
Yield0.5lbsVSS/lbsBOD
InfluentBOD300mg/L
EffluentBOD10mg/L
InfluentTSS350mg/L
EffluentTSS5mg/L
VolatileFractionofTSS75%
CompactedSludgeConc.20%
SpecificGravityofSludge1.005
SolidsProduction:

VolumeofSludgeProduced:
SludgeRetentionTimeinPrimarySettlingBasin:
4.Discussion
TheShallotteWWTPwillhavesufficientcapacityandresourcestomanagealloftheresiduals
generatedattheWWTPsite.Asdemonstratedabove,thelagoonshavesufficientcapacitytostore
sludgegeneratedfromthetreatmentprocess.Thelagoonsarecleanedoutonamaintenance
schedule,sothereisnoriskofsignificantlyreducingtreatmentcapacitywithinthelagoons.
Screenedandgritsolidswillbestoredindumpstersandcollectedbythelocalwastemanagement
facilityforlandfilldisposal.