2007 10 22 guide electroplating guidance

8/12/2019 2007 10 22 Guide Electroplating Guidance

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\''" "" - ' _ " _ _______w-.....---------"Unite'd'States ' EffluentGuidel inesDivision EPA-440/1-84/091 g,EhvirpnnnentalProtect ion andPermi t sDivision February1984

%' ' Agency WashingtonDC20460I -I.IM - ------ ----__

.-HiPA Guidance IVIariyalforElectroplating

I; andMetalRnishingPretreatmentStandards


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GUIDANCEMANUALFOR

ELECTROPLATINGANDMETALFINISHINGPRETREATMENTSTANDARDS

preparedbyThe

Effluent GuidelinesDivis ionOfficeofWaterRegulationsandStandards

andPermitsDivision

OfficeofWaterEnforcementandPermits

February1984U.S.EnviromentalProtect ionAgency

401MStreetS.W.Washirqton,DC 20460


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isasiUNITEDSTATESENVIRONMENTALPROTECTIONAGENCY

WASHINGTON.D.C.20460OFFICEOF WATER

MEMORANDUMSUBJECT; GuidanceManualforElectroplatingand

MetalFinishingPretreatmentStandards FROM:

TO;

MarthaG.Prothro,DirecPermitsDivision(EN-336JefferyD.Denit,Direct EffluentGuidelinesDiviUsers oftheGuidance Manual

Thismanualprovides informationtoassistControlAuthorities andApprovalAuthorities inimplementingtheNationalCategorical PretreatmentStandardsfortheElectroplatingandMetalFinishingPointSourceCategories (40CFRParts413and433, respectively).It isdesignedtosupplementthemoredetaileddocumentslistedasreferences inthemanual; it isnotdesignedtoreplacethem.Ifyouneedmorecompleteinformationonaspecific item, you shouldrefertotheappropriatereference.

EPAdevelopedthismanualtofillseveralneeds. First, itshouldbeusefultoControlAuthorities inrespondingtomost routine inquiriesfromregulatedmanufacturers. Morecomplex inquiriesmayrequiretheuseofthelistedreferences.

Second,ApprovalAuthoritiesshouldfindthismanualuseful inrespondingtospecificcategorydeterminationrequestssub

mittedby industriesundertheElectroplatingandMetalFinishing regulations. Inaddition,manyintegratedfacilitieshaveraisedquestionsregardingtherelationshipbetweentheElectroplating regulationandtheMetalFinishingregulationandbetweenthe

MetalFinishingregulationandotherregulationslisted inSection 433.10oftheMetalFinishingregulation. Themanualwillprovide informationonrespondingtocategorydeterminationrequestsandquestionsfromintegratedfacilities.


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Finally, themanualaddressesapplicationof thecombined

wastestreamformulatointegratedfacilitieswithregulatedandunregulatedwastestreams. Italsoprovidescurrent informationonremovalcreditsandthestatusofthefundamentallydifferent factorsvariance

provisionin

lightof therecentcourt

decision.

It furtherexplainshowfacilitiessubjecttothese regulations mayusethecertificationproceduretominimizetheirsampling andanalysisfortotaltoxicorganicpollutants.

WehopethatPOTWswillfindthismanualtobeausefultool inimplementingtheElectroplatingandMetalFinishing CategoricalPretreatmentStandards. Itmayalsobeuseful inimplementingothercategoricalpretreatmentstandards. PleasefeelfreetowritetoeithertheOfficeofWaterRegulations andStandards (WH-551) ortheOfficeofWaterEnforcementandPermits (EN-336) withsuggestions, additions, orimprovements.


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ACKNOWLEDGEJIENTSWewishtoacknowledgetheconsiderableeffortsandco


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2-4

TABLEOFCONTENTSPAGE

1. INTRODUCTION 1-11.1 HISTORYOFTHEELECTROPLATINGANDMETALFINISHINGCATEGORICALPRETREATMENTSTANDARDS 1-2

2. ELECTROPLATINGCATEGORICALPRETREATMENTSTANDARDS 2-12.1 AFFECTEDINDUSTRY 2-12.2 EXCEPTIONSFROMREGULATIONCOVERAGE 2-32.3 PRETREATMENTSTANDARDSFORTHEELECTROPLATINGCATEGORY____2.4 POLLUTANTSEXCLUDEDFROMREGULATION 2-72.5 COMPLIANCEDATES 2-7

3. METALFINISHINGCATEGORICALPRETREATMENTSTANDARDS 3-13.1 AFFECTEDINDUSTRY 3-13.2 EXCEPTIONSFROMREGULATIONCOVERAGE 3-13.4 POLLUTANTSEXCLUDEDFROMREGULATION 3-163.5 COMPLIANCEDATES 3-193,6 ALTERNATIVECYANIDELIMITATION 3-19

4. TREATMENTTECHNOLOGIES 4-14.1 TREATMENTOFCOMMONMETALSWASTES 4-14.2 TREATMENTOFCOMPLEXEDMETALWASTES 4-34.3 TREATMENTOFPRECIOUSMETALSWASTES 4-34.4 TREATMENTOFHEXAVALENTCHROMIUM 4-44.5 TREATMENTOFCYANIDEWASTES 4-44.6 TREATMENTOFOILYWASTES 4-54.7 IN-PLANTCONTROLOFTOXICORGANICS 4-54.8 TREATMENTOFSLUDGES 4-64.9 IN-PROCESSCONTROLTECHNOLOGIES 4-6

5. REQUIREMENTSOFTHEGENERALPRETREATMENTREGULATIONS 5-15.1 INTRODUCTION 5-15.2 CATEGORYDETERMINATIONREQUEST 5-2


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1-3

3-17

LISTOFTABLESANDFIGURESTable Page 1.1 Breakdownofthe

Electroplating/MetalFinishing

Industry.....

2.1 PretreatmentStandardsforExistingSources-

ElectroplatingCategory 2-52.2 ComplianceDatesforElectroplatingPretreatmentStandards... 2-73.1 MetalFinishingCategoryUnitOperations 3-23.2 Potential.WastewaterPollutantsGeneratedbyMetal

FinishingCategoryUnitOperations 3-123.3 PretreatmentStandardsfortheMetalFinishingCategory......3.4 LongTermConcentrationAverages 3-183.5 ComplianceDatesforMetalFinishingPretreatment

Standards 3-20

5.2 CombinedWastestreamFormulas 5-135.3 CombinedWastestreamFormulaExampleCalculation 5-145.4 CombinedWastestreamFormulaExampleCalculation 5-15Figure3.1 SchematicShowingExampleofOverlapCoverageof

CategoricalStandardsatIntegratedFacilities 3-154.1 WastewaterTreatmentSchematic 4-2


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1. INTRODUCTION

TheNationalPretreatmentProgramestablishesanoverallstrategyforcontrollingtheintroductionofnondomesticwastestopubliclyownedtreatmentworks(POTWs)inaccordancewiththeoverallobjectivesoftheCleanWaterAct. Sections307(b)and(c)oftheActauthorizetheEnvironmentalProtectionAgencytodevelopnationalpretreatmentstandardsfornewandexistingdischargerstoPOTWs. TheActmadethesepretreatmentstandardsenforceableagainstdischargerstopubliclyownedtreatmentworks.

TheGeneralPretreatmentRegulations(40CFRPart403)establishadministrativemechanismsrequiringnearly1,700POTWstodeveloplocalpretreatmentprogramstoenforcethegeneraldischargeprohibitionsandspecificCategoricalPretreatmentStandards. TheseCategoricalPretreatmentStandardsaredesignedtopreventthedischargeofpollutantswhichpassthrough,interferewith,orareotherwiseincompatiblewiththeoperationofthePOTWs. Thestandardsaretechnology-basedforremovaloftoxicpollutantsandcontainspecificnumericallimitationsbasedonanevaluationofspecifictechnologiesfortheparticularindustrialcategories. Asaresultofasettlementagreement,

theEPAwasrequired

todevelop

Categorical

PretreatmentStandardsfor34industrialcategorieswithaprimaryemphasison65classesoftoxicpollutants.

ThismanualwillprovideguidancetoPOTWsontheapplicationandenforcementoftheCategoricalPretreatmentStandardsfortheElectroplatingandMetalFinishingCategories. Thisdocumentisbasedprimarilyontwosources: FederalRegisternotices,whichincludetheofficialannouncementsoftheCategoricalStandards,andtheFinalDevelopmentDocumentsforElectroplatingandMetalFinishing,whichprovideasummaryofthetechnicalsupportfortheregulations. Additionalinformationontheregulations,manufacturingprocesses,andcontroltechnologiescanbefoundinthesesources. Alistingofthereferencesusedinthedevelopmentofthismanualisprovidedattheendofthisdocument.

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1.1 HISTORYOFTHEELECTROPLATINGANDMETALFINISHINGCATEGORICAL

PRETREATMENTSTANDARDSThereare13,500plantsintheelectroplating/metalfinishingindustry.

Manydischargewastewatersfromseveralmetalfinishingoperationsotherthan,andinadditionto,electroplating. Part413(electroplating)currentlyappliesonlytoflowsfromthesixspecifiedelectroplatingprocesses. ThesePart433(metalfinishingregulations)willapplytothoseelectroplatingstreamsandalsotowastestireamsfrommostothermetalfinishingoperationswithinthesameplants. ThePart433PSESwillapplyonlytoplantsalreadycoveredbyPart413;howeverPart433willoftencoveradditionalwastewaterwithinthesameplants. ThusthePart433limitsondischargeoftoxicmetals,toxicorganics,andcyanidewillapplytomostfacilitiesintheelectroplating/metalfinishingindustry.

TheindustrycanbedividedintothesectorsindicatedonTable1.1.Facilitiesareeither"captives"(thosewhichinacalendaryearownmorethan50%[areabasis]ofthematerialsundergoingmetalfinishing);or"jobshops"(thosewhichinacalendaryeardonotownmorethan50%[areabasis]ofmaterialundergoingmetalfinishing).

Captivescanbefurtherdividedbytwodefinitions: "integrated"plantsarethosewhich,priortotreatment,combineelectroplatingwastestreamswithsignificantprocesswastestreams-notcoveredbytheelectroplatingcategory;"non-integrated"facilitiesarethosewhichhavesignificantwastewaterdischargesonlyfromoperationsaddressedbytheelectroplatingcategory. Manycaptives(50%)are"integrated"facilities. Whereascaptivesoftenhaveacomplexrangeofoperations,jobshopsusuallyperformfeweroperations. Intheoryjobshopscanbedividedlikecaptives;inactuality,however,approximately97%ofalljobshopsinthisindustryare"non-integrated."

Pretreatmentstandardsfortheelectroplatingindustrywerefirstestablishedin1974butitwasnotuntilpromulgationof40CFRPart413onSeptember7, 1979thatElectroplatingCategoricalPretreatmentStandardsbecameareality. The1979Standardsestablishedspecificnumericallimitationsfordischargersfallingwithinsevensubcategories. Shortlythereafter,

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Table1.1BREAKDOWNOFTHE V


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petitionstoreviewtheelectroplatingpretreatmentstandardswerefiledintheCourtofAppealsbyseveralindustrygroups. EPAreachedasettlementagreementwiththeindustrygroupsandagreedtoadoptchangestotheStandardswhichwerepromulgatedonJanuary28, 1981. ThemajorchangesincorporatedbytheI98IamendmentstotheElectroplatingStandardsincluded:

I) Revisionofthedailymaximumlimitationfortotalcyanidefrom0.8to1.9mg/1

2) Revisionof30-dayaveragelimitsto4-dayaveragelimits3) Adoptionoftheconceptofintegratedandnon-integratedfacilities4) Extensionofcompliancedates5) Recognitionofthedevelopmentofadditionalpretreatmentstandards

tobecalled"MetalFinishing"whichwouldregulateprocessescurrentlyfallingunderelectroplatingaswellasmanyothermetalfinishingprocesses. However,EPAstatedthatinlightofthepotentiallysevereeconomicimpactoftheseanticipatedregulationsonthejobshop(andindependentprintedcircuitboard)segmentoftheIndustry,theAgencywouldnotimposemorestringentpretreatmentstandardsforthatsegmentoftheindustryforseveralyears.

InaccordancewiththeAgency'splan,EPApromulgatedtheMetalFinishingCategoricalPretreatmentStandardsonJuly15, 1983as40CFRPart433. Theeffectofthe1983MetalFinishingStandardswastocreateanewcategory-MetalFinishing-whichmostelectroplaterswouldhavetocomplywithfollowingtheircompliancewiththeElectroplatingStandard. Thesesubsequentlimitswouldapplyuniformlytodischargesfromelectroplatingandothermetalfinishingoperations. Thiswouldmeetindustry'srequestsforequivalentlimitsforprocesslinesoftenfoundtogetherandwouldgreatlyreducetheneedforthecombinedwastestreamformula(seeSection5.5). OncethecompliancedatefortheMetalFinishingStandardsisreached,allfirms,conductingoneormoreofthesixbasicoperationsoftheElectroplatingCategory(seeSection2.1)mustcomeintocompliancewiththeMetalFinishingPretreatmentStandards,withtheexceptionofexistingjobshopelectroplatersandindependentprintedcircuitboardmanufacturers. ExistingindirectjobshopelectroplatersandindependentprintedcircuitboardmanufacturersmuststillcomplywiththePart413ElectroplatingPretreatmentStandardsandareexemptfromthePart433MetalFinishingStandards.

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/

Non-integratedandintegratedelectroplatersmustcomplywithElectroplatingPretreatmentStandardsforExisting'Sources(PSES)forMetalsandCyanidebyApril27, 1984,andJune"301984,respectively. Allelectro-platersmustcomplywiththeTotalToxicOrganics(TTO)PSESbynolaterthanJuly15, 1986(SeeTable2.2).

ElectroplaterssubjecttotheMetalFinishingPSESmustcomplywiththeMetals,Cyanide,andFinalTTOPSESbynolaterthanFebruary15, 1986(SeeTable3.5). Afterthisdate,theMetalFinishingPSESsupercedetheElectroplatingPSES. WiththeexceptionofplantscoveredbytheIronandSteelstandards,electroplaterssubjecttotheMetalFinishingPSESmustcomplywithaninterimTTOPSESbynolaterthanJune30, 1984. Amorecompletediscussionofcompliancedatesispresentedinsubsequentsectionsofthismanual.

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2. ELECTROPLATINGCATEGORICALPRETREATMENTSTANDARDS(40CFRPART413)

2.1 AFFECTEDINDUSTRYTheElectroplatingStandardsareapplicabletowastewaterfromanyorall

ofthesesixspecificoperations(SeetheElectroplatingFinalDevelopmentDocument).

Thesesixelectroplatingoperationsarebrieflydiscussedbelow:1. Elec t rip la t ingistheproductionofathinsurfacecoatingofone

metaluponanotherbyelectrodeposition. Ferrousornonferrousbasismaterialsmaybecoatedbyavarietyofcommon(copper,nickel,lead,chromium,brass,bronze,zinc, tin,cadmium,iron,aluminumorcombinationsthereof)orprecious(gold,silver,platinum,osmium,iridium,palladium,rhodium,indium,ruthenium,orcombinationsthereof)metals. Inelectroplating,metalionssuppliedbythedissolutionofmetalfromanodesorotherpieces,arereducedontheworkpieces(cathodes)whileineitheracid,alkaline,orneutralsolutions.Theelectroplatingbathscontainmetalsalts,alkalies,andotherbathcontrolcompoundsinadditiontoplatingmetalssuchascopper,nickel,silverorlead. Manyplatingsolutionscontainmetallic,metallo-organic,andorganicadditivestoinducegrainrefining,levelingoftheplatingsurface,anddepositbrightening.

2. Eleetroless Platingisthechemicaldepositionofametalcoatingonaworkpiecebyimmersioninanappropriateplatingsolution.Electricityisnotinvolved,thereforeuniformdepositsareeasilyobtained. Copperandnickeleleetrolessplatingforprintedcircuitboardsarethemostcommonoperations. Ineleetrolessnickelplatingthesourceofnickelisasalt,andareducerisusedtoreducethenickeltoitsbasestate. Acomplexingagentisusedtoholdthemetalioninsolution. Immersionplating,whichforpurposesofthis

2-1

1. Electroplating2. EleetrolessPlating3. Anodizing4. Coatings5. ChemicalEtchingandMilling6. PrintedCircuitBoardManufacturing


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regulationIsconsideredpartofelectrolessplating,producesametaldepositbychemicaldisplacement;however, ItIsnotanautocatalytlcprocessbutIspromotedbyoneoftheproductsofthe reaction. Immersionplatingbathsareusuallyformulationsofmetalsalts, alkaliesandcomplexlngagents (typicallycyanideorammonia).

3.Anodizing

Isanelectrochemicalprocess

which

convertsthemetalsurfacetoacoatingofanInsolubleoxide. Aluminu mIsthemost frequentlyanodlzedmaterial. Theformationoftheoxideoccurswhen thepartsaremadeanodicIndilutesulfuricorchromicacidsolutions. Theoxidelayerbeginsformationattheextremeoutersurface, andasthereactionproceeds, theoxidegrowsintothe

metal. Chromicacidanodiccoatingsaremoreprotectivethansulfuricacidcoatingsandareusedifacompleterinsingofthepart cannotbeachieved.

Anodizingwastewatertypicallycontainsthebasismaterialandeitherchromicorsulfuricacid. Whendyeingofanodlzedcoatingsoccurs,thewastewaterswillcontainchromiumorothermetalsfromthedye.OtherpotentialpollutantsIncludenickelacetate(usedtosealanodiccoatings)orothercomplexesandmetalsfromdyesandsealers.

4. CoatingsIncludechromatlng,phosphatlng,metalcoloringandpassivatlng. Pollutantsassociatedwiththeseprocessesenterthewastestreamthroughrinsingandbatchdumpingofprocessbaths. Theprocessbathsusuallycontainmetalsalts, acids, bases, anddissolvedbasismaterials. Inchromatlng,aportionofthebasemetalisconvertedtoacomponentoftheprotectivefilmformedbythecoatingsolutionscontaininghexavalentchromiumandactiveorganicorinorganiccompounds. Phosphatecoatingsareformedbytheinraiersionofsteel, iron, orzincplatedsteelinadilutesolutionofphosphoricacidplusotherreagentstoconditionthesurfacesforcoldformingoperations, prolongthelifeoforganiccoatings,providegoodpaintbondingandimprovecorrosionresistance. Metal coloringInvolvesthechemicalmethodofconvertingthemetalsurfaceintoanoxideorsimilarmetalliccompoundtoproduceadecorative finish. Avarietyofsolutionsutilizingmanymetalsmaycontribute tothewastestream. Passivatlngistheprocessofformingaprotectivefilmonmetalsbyimmersioninanacidsolution, usuallynitric acidornitricacidwithsodiumdlchromate.

5. Etching and Chemical Millingareprocessesusedtoproducespecificdesignconfigurationsorsurfaceappearancesonpartsbycontrolleddissolutionwithchemicalreagentsoretchants. ChemicaletchingIsthesameprocessaschemicalmillingexcepttheratesanddepthsofmetalremovalrererereusuallymuchgreaterinchemicalmilling. Themajorwastestreamconstituentsarethedissolvedbasismaterialandetchingsolutions.

6. Printed Circuit Board ManufacturingInvolvestheformationofacircuitpatternofconductivemetal(usuallycopper)onnonconductlveboardmaterialssuchasplasticorglass. Therearefivebasicsteps

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involvedinthemanufacturingofprintedcircuitboards: cleaningandsurfacepreparation,catalystandelectrolessplating,patternprintingandmasking,electroplating,andetching.Wastewaterisproducedinthemanufacturingofprintedcircuitboardsfromthefollowingprocesses:

1

a. Surfacepreparation-Therinsesfollowingscrubbing,alkalinecleaning,acidcleaning,etchback,catalystapplication,andactivation.

b. Electrolessplating-Rinsesfollowingtheelectrolessplatingstep.

c. Patternplating-Rinsesfollowingacidcleaning,alkalinecleaning, copperplating,andsolderplating.

d. Etching-Rinsesfollowingetchingandsolderbrightening.e. Tabplating-Rinsesfollowingsolderstripping,scrubbing,acidcleaning,andnickel,gold,orotherplatingoperations.f. Immersionplating-Rinsesfollowingacidcleaningandinmiersion

tinplating.Additionally,watermaybeusedforsubsidiarypurposessuchasrinsingawayspills,airscrubbingWater,equipmentwashing,anddumpingspentprocesssolutions. Theprincipalconstituentsofthewastestreamsfromtheprintedcircuitboardindustryaresuspendedsolids,copper,fluorides,phosphorus,tin,palladium,andchelatingagents. LowpHvaluesarecharacteristicofthewastesbecauseof- thenecessaryacidcleaningandsurfacepretreatment.

Inadditiontotheaboveoperations,theElectroplatingStandardsalsoapplytotherelatedoperationsofalkalinecleaning,acidpickle,andstrippingwheneachoperationisfollowedbyarinse.2.2 EXCEPTIONSFROMREGULATIONCOVERAGE

OperationssimilartoelectroplatingwhicharespecificallyexemptfromcoverageundertheElectroplatingCategoricalPretreatmentStandardsinclude:

1. Electrowinningandelectrorefiningconductedaspartofnonferrrousmetalsmeltingandrefining(40CFRPart421);

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2. Metalsurfacepreparationandconversioncoatingconductedaspartofcoilcoating(40CFRPart465);

3. Metalsurfacepreparationandimmersionplatingorelectrolessplatingconductedasapartofporcelainenameling(40CFRPart466);

4. Electrodepositionofactiveelectrodematerials,electroimpregnation,andelectroformingconductedaspartofbatterymanufacturing(40CFRPart461);5. Metallicplatemakingandgravurecylinderpreparationconducted

withinprintingandpublishingfacilities;and6. ContinuousstripelectroplatingconductedwithinIronandsteel

manufacturingfacilities.7. Surfacetreatmentincludinganodizingandconversioncoatingcon

ductedaspartofaluminumforming(40CFRPart467).2.3 PRETREATMENTSTANDARDSFORTHEELECTROPLATINGCATEGORY

IndirectdischargersthatperformelectroplatingoperationsarecurrentlysubjecttotheElectroplatingCategoricalPretreatmentStandards(40CFRPart413). TheElectroplatingStandardsweredevelopedbasedonthebestpracticablecontroltechnology(BPT)andapplyonlytoexistingindirectsources(PSES). EPAestablishedPretreatmentStandardsonthebasisofconcentrationwithalternatemass-basedstandardsforElectroplating. Theproductionbasedstandardsarebasedonmilligramspersquaremeterofoperation. ElectroplatingStandardsarebasedondailymaximumandfourdayaveragevaluelimits(withfourdayaveragevaluelimitsdefinedastheaveragevaluefromfourconsecutivesamplingdays). ThePSESlimitationsforelectroplatersandthealternatemass-basedstandardsarepresentedinTable2.1. Notethatthelimitationsandthepollutantsregulatedaredifferentfordischargersoflessthan10,000gallonsperdayofregulatedElectroplatingprocesswastewaterascomparedtodischargersof10,000gallonsperdayormoreofregulatedElectroplatingprocesswastewater.

Also,allnewsourceswhichperformelectroplatingoperationsaresubjecttotheMetalFinishingregulations(40CFRPart433).

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TABLE2.1PRETREATMENTSTANDARDSFOREXISTINGSOURCES (PSES)

ELECTROPLATINGCATEGORY Facilities Discharging 38,000liters (10,000gallons)perdayPollutantCadmium(T)Chromium(T)Copper(T)Lead(T)Nickel(T)Zinc(T)Silver(T)(T)(T)(T)TotalMetals Cyanide,TTotalToxicOrganics (TTO) 1

DailyMaximum(mg/1)

1.2 7.04.5 0.64.14.2 1.2

10.51.92.13

Maximum4DayAverage

(mg/1)0.7 4.0 2.70.4 2.62.60.76.81.0

Cyanide,A =Cyanide, amenabletochlorination Cyanide (T)=Cyanide, Total(T) =TotalNoregulationofthemaximum4-dayaverageforTTO.'Thesilverpretreatmentstandardappliesonlytopreciousmetalsplating. TotalTotalTotalTotalmetalsisdefinedasthesumoftheconcentrationofcopper,nickel,totalchromium,andzinc.

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Silver (T)

TABLE2.1(continued)

AlternateMass-BasedLimitationsForElectroplatingSubcategoriesDischarging38,000liters(10,000gallons)perdayormore

Pollutant DailyMaximum(mg/sqmof Operation)Electroplating,Electroless

Plating,

Maximum4DayAverage(mg/sqmof Operation)

Electroplating,Electroless

Plating,ChemicalEtching

andMilling,Coatings,

PrintedCircuitBoard

ChemicalEtchingPrintedandMilling,Circuit

Coatings,BoardAnodizing_ ManufacturingAnodizing Manufacturing

Cadmium(T)Chromium,

(T)

Copper(T)Lead(T)Nickel(T)Zinc(T)

.1Totalmetals'Cyanide(T)

47273

17623160644741074

10762340153

365374935169

2915610516

1001022926739

65357

24136

22923260989

TTO-Maximumforanyonedayis2,13mg/11Thesilverpretreatmentstandardappliesonlytopreciousmetalsplating."Totalmetalsisdefinedasthesumofthemassesofcopper,nickel,totalchromium,andzinc.

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2.4 POLLUTANTSEXCLUDEDFROMREGULATION

TheEPAexcludedfromregulation7ofthe 126toxicpollutantswhichare givenpriorityconsideration(antimony, arsenic, asbestos, beryllium,mercury, selenium, andhallium).hallium).hallium).hallium). Thesepollutantsarefoundinonlyasmallnumberofsourcesandare

effectivelycontrolled

bythe

technologiesonwhichthelimits

arebased. 2.5 COMPLIANCEDATES

TheAgencydividedtheindustryintotwogroupsonthebasisofwaste watercomplexity:

a. Integratedfacility-afacilitywhichperformselectroplatingasonlyoneofseveraloperationsnecessaryformanufactureofaproductatasinglephysicallocation,whichhassignificantquantitiesofprocesswastewaterfromnonelectroplatingoperation, andwhich, priortooratthepointoftreatment (orproposedtreatment), combinesone ormoreelectroplatingprocesswaterlineswithoneormoreplantsewerscarryingprocesswastewaterfromnon-electroplatingmanufacturingoperations.

b. Non-integrated-anyfacilitywhichisnotintegrated.Thisdivisionresultsindifferentcompliancedatesasshownin

Table2.2, below. TABLE2.2

COMPLIANCEDATESFORELECTROPLATINGPRETREATMENTSTANDARDS40CFRPART413ExistingIndirectDischargers _ComplianceDates_

PollutantParameter

MetalsandCyanideNon-Integrated

Facilities

April27,1984IntegratedFacilities June30,1984

TotalToxicOrganics(TTO) July15, 19862-7

July15,1986


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3, METALFINISHINGCATEGORICALPRETREATMENTSTANDARDS(40CFRPART433)

3.1 AFFECTEDINDUSTRYTheMetalFinishingCategorycoverswastewaterdischargesfrom46unit

operations,thesixoperationspreviouslyaddressedbytheElectroplatingregulation,plusanadditional40operations. Ifanyofthesixelectroplatingoperationsarepresent,thentheMetalFinishingpretreatmentregulationsapplytowastewaterfromanyofthe46listedmetalfinishingoperations. IfafacilitydoesnotperformatleastoneofsixElectroplatingoperations,itisnotsubjecttotheMetalFinishingregulation. ThesemetalfinishingunitoperationsaresummarizedanddescribedinTable3.1. Table3.2summarizesthewastewaterspotentiallygeneratedbyeachofthemetalfinishingunitoperations. SincetheStandardsregulateprocessesandnotindustrygroups,specificSICcodesdonotdeterminecoverage.3.2 EXCEPTIONSFROMREGULATIONCOVERAGE

ExcludedfromtheMetalFinishingregulationsareallexistingindirectdischargingjobshopelectroplaters, independentprintedcircuitboardmanufacturers,andanyfacilitywhichdoesnotperformatleastoneofthesixbasicElectroplatingprocesses. Jobshopsaredefinedasthosefacilitieswhichinacalendaryearown50%(areabasis)orlessofthematerialundergoingmetalfinishing. IndependentPrintedCircuitBoardManufacturers(IPCBMs)aredefinedasfacilitieswhichmanufactureprintedcircuitboardsprincipallyforsaletoothercompanies. ThesefacilitiesremainsubjectonlytotheElectroplating(Part413)Standards,primarilytominimizetheeconomicimpacttotheserelativelysmallfacilities. AlsoexcludedfromtheMetalFinishingregulationsarethosefacilitieswhichperformmetallicplatemakingandgravurecylinderpreparationconductedwithinprintingandpublishingfacilities.

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TABLE3.1. METALFINISHINGCATEGORYUNITOPERATIONS

UnitOperations SummaryDescriptionofUnitOperations1. Electroplating Theproductionofathinsurfacecoatingofonemetaluponanotherby

electrodeposition. Ferrousornonferrousbasismaterialsmaybecoatedbyavarietyofcommon(copper,nickel, lead,chromium,brass,bronze,zinc, tin,cadmium, iron,aluminumorcombinationsthereof)orprecious(gold,silver,platinum,osmium,iridium,palladium,rhodium, indium,ruthenium,orcombinationsthereof)metals. Inelectroplating,metalionssuppliedbythedissolutionofmetalfromanodesorotherpieces,arereducedontheworkpieces(cathodes)whileineitheracid,alkaline,orneutralsolutions.

2. ElectrolessPlating Thechemicaldepositionofametalcoatingonaworkpiecebyimmersioninanappropriateplatingsolutioninwhichelectricityisnotinvolved.Copperandnickelelectrolessplatingforprintedcircuitboardsarethemostcommonoperations. Immersionplating,whichforpurposesoftheMetalFinishingregulationisconsideredpartofelectrolessplating,producesametaldepositbychemicaldisplacement.

3. Anodizing Anelectrochemicalprocesswhichconvertsthemetalsurfacetoacoatingofaninsolubleoxide. Aluminumisthemostfrequentlyanodizedmaterial. Theformationoftheoxideoccurswhenthepartsaremadeanodicindilutesulfuricorchromicacidsolutions. Theoxidelayerbeginsformationattheextremeoutersurface, andasthereactionproceeds, theoxidegrowsintothemetal.

4. Coatings Anyoperationthatincludeschromating,phosphating,metalcoloringandpassivating. Inchromating,aportionofthebasemetalisconvertedtoacomponentoftheprotectivefilmformedbythecoatingsolutionscontaininghexavalentchromiumandactiveorganicorinorganiccompounds.Phosphatecoatingsareformedbytheimmersionofsteel,iron,orzincplatedsteelinadilutesolutionofphosphoricacidplusotherreagentstoconditionthesurfacesforfurtherprocessing. Metalcoloringinvolvesthechemicalmethodofconvertingthemetalsurfaceintoan


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UnitOperationsTABLE3.1.METALFINISHINGCATEGORYUNITOPERATIONS(Continued)

SummaryDescriptionofUnitOperationsoxideorsimilarmetalliccompoundtoproduceadecorativefinish.Passivatingistheprocessofformingaprotectivefilmonmetalsbyimmersioninanacidsolution,usuallynitricacidornitricacidwithsodiumdichromate.

5. EtchingandChemicalMillingPrintedCircuitBoardManufacturing

7. Cleaning

8. Machining

9. Grinding

Theseoperationsareusedtoproducespecificdesignconfigurationsorsurfaceappearancesonpartsbycontrolleddissolutionwithchemicalreagentsoretchants.Chemicaletchingisthesameprocessaschemicalmillingexcepttheratesanddepthsofmetalremovalareusuallymuchgreaterinchemicalmilling.Thisoperationinvolvestheformationofacircuitpatternofconductivemetal(usuallycopper)onnonconductiveboardmaterialssuchasplasticorglass.Therearefivebasicstepsinvolvedinthemanufacturingofprintedcircuitboards:cleaningandsrfacepreparation,catalystandelectrolessplating,patternprintingandmasking,electroplating,andetching.Thisoperationinvolvestheremovalofoil,grease,anddirtfromthebasismaterialusingwaterwithorwithoutdetergentsorotherdispersingagents.Acidcleaningisaprocessinwhichanacidisusedwithawettingagentordetergenttoremoveoil,grease,dirt,oroxidefromthemetalsurface.Thisoperationinvolvesthegeneralprocessofremovingstockfromaworkpiece

byforcing

acutting

toolthrough

theworkpiece,

thereby

removingachipofbasismaterial.Machiningoperationsincorporatetheuseofnaturalandsyntheticoilsforcoolingandlubrication.Thisoperationinvolvestheprocessofremovingstockfromaworkpiecebytheuseofatoolconsistingofabrasivegrainsheldbyarigidorsemirigidbinder.Naturalandsyntheticoilsareusedforcoolingandlubricationinmanygrindingoperations.


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UnitOperations10, Polishing

11. BarrelFinishing(orTumbling)

12. Burnishing

TABLE3.1,METALFINISHINGCATEGORYUNITOPERATIONS(Continued)SummaryDescriptionofUnitOperationsThisabradingoperationisusedtoremoveorsmoothoutsurfacedefects(scratches,pits,toolmarks,etc.)thatadverselyaffecttheappearanceorfunctionofapart.Areacleaningandwashdowncanproducewastesthatenterwastewaterstreams.Thewasteswouldbelongtothecommonmetalsandoilywastetypes.Thisoperationisacontrolledmethodofprocessingpartstoremoveburrs,scale,flash,andoxidesaswellastoimprovesurfacefinish.Barrelfinishingproducesauniformityofsurfacefinishnotpossiblebyhandfinishingandisgenerallythemosteconomicalmethodofcleaningandsurfaceconditioning.Wastewaterisgeneratedbyrinsingofpartsfollowingthefinishingoperationandbyperiodicdumpingofprocesssolutions.Contributionstothecommonmetals,hexavalentchromium,cyanide,andoilywastetypescouldbemadebythisoperation,dependinguponthechemicalsolutionsemployed.Thisoperationinvolvestheprocessoffinishsizingorsmoothfinishingaworkpiece(previouslymachinedorground)bydisplacement,ratherthanremoval,ofminutesurfaceirregularities.Wastesmaycomefromspills,leaks,processsolutiondumpsandpost-finishrinsingandcouldcontributetothecommonmetals,preciousmetals,andoilywastetypesdependinguponthebasismaterialfinished.Inaddition,sodiumcyanide(NaCN)maybeusedasawettingagentandrustinhibitor(forsteel),thuscontributingcyanidewastesfromthisoperation.13. ImpactDeformation Thisoperationinvolvestheprocessofapplyinganimpactforcetoaworkpiecesuchthattheworkpieceispermanentlydeformedorshaped.Wastescontainingcommonmetalsandoilywastesmaycomefromcleaningthepartsorcleanupofleaksorspills.


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TABLE3.1. METALFINISHINGCATEGORYUNITOPERATIONS(Continued)UnitOperations14. PressureDeformation15. Shearing

16. HeatTreating

17. ThermalCutting18. Welding

SummaryDescriptionofUnitOperationsThisoperationinvolvestheprocessofapplyingforce(ataslowerratethanatimpactforce)topermanentlydeformorshapeaworkpiece.Wastescontainingcommonmetalsandoilywastesmaycomefromcleaningthepartsorcleanupofleaksorspills.Thisoperationinvolvestheprocessofseveringorcuttingaworkpiecebyforcing

asharp

edge

oropposed

sharp

edges

intotheworkpiece

stressing

thematerialtothepointofshearfailureandseparation.Wastescontainingconmionmetalsandoilywastesmaycomefromcleaningthe'partsorcleanupofleaksorspills.Thisoperationinvolvesthemodificationofthephysicalpropertiesofaworkpiecethroughtheapplicationofcontrolledheatingandcoolingcycles.Wastewaterisgeneratedthroughrinses,bathdischarges,spills,andleaks,andoftencontainthesolutionconstitutentsaswellasvariousscales,oxides,andoils.Thisoperationinvolvestheprocessofcutting,slottingorpiercingaworkpieceusinganoxyacetyleneoxygenlanceorelectricarccuttingtool.Watermaybeusedforrinsingorcoolingofpartsandequipmentfollowingthisoperation.Wastewaters'producedwouldcontributetothecommonmetalsandoilywastetypes.Thisoperationinvolvestheprocessofjoiningtwoormorepiecesofmaterialbyapplyingheat,pressureorboth,withorwithoutfillermaterial,toproducealocalizedunionthroughfusionorrecrystalliza-tionacrosstheinterface.Thisoperationisfollowedbyquenching,coolingorannealinginasolutionofwateroremulsifiedoils.Whenthisisdone,wastesproducedcanbelongtothecommonmetalswastetype.


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TABLE3.1. METALFINISHINGCATEGORYUNITOPERATIONS(Continued)

UnitOperations SunnnaryDescriptionofUnitOperations19. Brazing Thisoperationinvolvestheprocessofjoiningmetalsbyflowingathin,

capillarythicknesslayerofnonferrousfillermetalintothespacebetweenthem. Bondingresultsfromtheintimatecontactproducedbythedissolutionofasmallamountofbasemetalinthemoltenfillermetal,withoutfusionofthebasemetal. Theternbrazingisusedwherethetemperatureexceeds (800?). Thisoperationisfollowedbyquenching,coolingorannealinginasolutionofwateroremulsifiedoils. Whenthisisdone,wastesproducedcanbelongtothecommonmetalswastetype.

20. Soldering Thisoperationinvolvestheprocessofjoiningmetalsbyflowingathin(capillarythickness)layerofnonferrousfillermetalintothespacebetweenthem. Bondingresultsfromtheintimatecontactproducedbythedissolutionofasmallamountofbasemetalinthemoltenfillermetal,withoutfusionofthebasemetal. Thetermsolderingisusedwherethetemperaturerangefallsbelow425F(800F). Thisoperationisfollowedbyquenching,coolingorannealinginasolutionofwateroremulsifiedoils. Whenthisisdone,wastesproducedcanbelongtothecommonmetalswastetype.

21. FlameSpraying Thisoperationinvolvestheprocessofapplyingametalliccoatingtoaworkpieceusingfinelypowderedfragmentsofwire,togetherwithsuitablefluxes,whichareprojectedthroughaconeofflameontotheworkpiece.Thisoperationisfollowedbyquenching,coolingorannealinginasolutionofwateroremulsifiedoils. Whenthisisdone,wastesproducedcanbelongtothecommonmetalswastetype.

22. SandBlasting Thisoperationinvolvestheprocessofremovingstock,includingsurfacefilms,fromaworkpiecebytheuseofabrasivegrainspneumaticallyimpingedagainsttheworkpiece.


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TABLE3.1. METALFINISHINGCATEGORYUNITOPERATIONS(Continued)UnitOperations23. AbrasiveJetMachining

24. ElectricalDischargeMachining

25. ElectrochemicalMachining

26. ElectronBeamMachining

SuimnaryDescriptionofUnitOperationsThisoperationisamechanicalprocessforcuttinghardbrittlematerials.Itissimilartosandblastingbutusesmuchfinerabrasivescarriedathighvelocities(500-3000fps)byaliquidorgas"stream.'Wastewatercanbeproducedthroughsolutiondumps,spills,leaksorwashdownsofworkareasandcontributestothecommonmetalsandoilywastetypes.Thisoperationisaprocesswhichcanremovemetalfromanymetalwithgooddimensionalcontrol.Themachiningactioniscausedbytheformationofanelectricalsparkbetweenanelectrode,shapedtotherequiredcontour,andtheworkpiece.Rinsingofmachinedpartsandworkareacleanupscangeneratewastewaterswhichalsocontainbasematerials.Thesewastewaterscontributetothecommonmetalsandoilywastetypes.Thisoperationisaprocessbasedonthesameprinciplesusedinelectroplatingexcepttheworkpieceistheanodeandthetoolisthecathode.Electrolyteispumpedbetweentheelectrodesandapotentialappliedwhichresultsinremovalofthemetal.Inadditiontostandardchemicalformulations,inorganicandorganicsolventsaresometimesusedaselectrolytesforelectrochemicalmachiningandwiththebasismaterialbeingmachined,canenterwastesteamsviarinsedischarges,bathdumps,andfloorspills.Generatedwastescanbelongtothecommonmetals,cyanide,andsolventwastetypesdependinguponthesolventused.This

operationisathermoelectric

processwhereby

heatisgenerated

by

highvelocityelectronsimpingingonpartoftheworkpiece.Atthepointwheretheenergyoftheelectronsisfocused,itistransformedintosufficientthermalenergytovaporizethemateriallocallyandisgenerallycarriedoutinavacuum.


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TABLE3.1. METALFINISHINGCATEGORYUNITOPERATIONS(Continued)

UnitOperations27. LaserBeamMachining28. PlasmaArcMachining

29. UltrasonicMachining30. Sintering

31. Laminating

32. HotDipCoating

SummaryDescriptionofUnitOperationsThisoperationistheprocesswherebyahighlyfocusedmonochromaticcollimatedbeamoflightisusedtoremovematerialatthepointofimpingementonaworkpiece.Laserbeammachiningisathermoelectricprocesswithmaterialremovallargelyaccomplishedbyevaporation,althoughsomematerialisremovedintheliquidstateathighvelocity.Thisoperationistheprocessofmaterialremovalorshapingofaworkpiecebyahighvelocityjetofhightemperatureionizedgas.Agas(e.g.,nitrogen,argon,orhydrogen)ispassedthroughanelectricarccausingittobecomeionizedandraisedtotemperaturesinexcessof16,649C(30,000F).Therelativelynarrowplasmajetmeltsanddisplacestheworkpiecematerialinitspath.Thisoperationisamechanicalprocessdesignedtoeffectivelymachinehard,brittlematerials.Itremovesmaterialbytheuseofabrasivegrainswhicharecarriedinaliquidbetweenthetoolandthework,andwhichbombardtheworksurfaceathighvelocity.Thisoperationistheprocessofformingamechanicalpartfromapowderedmetalbyfusingtheparticlestogetherunderpressureandheat.Thetemperatureismaintainedbelowthemeltingpointofthebasismetal.Thisoperationistheprocessofadhesivebondinglayersofmetal,plastic,orwoodtoformapart.Waterisnotoftenusedinthisoperation;however,occasionalrinsingorcoolingmayoccurinconjunctionwithlaminating. Thewastegeneratedcouldcontributetothecommonmetalsandoilywastetypes.Thisoperationistheprocessofcoatingametallicworkpiecewithanothermetaltoprovideaprotectivefilmbyimmersioninamoltenbath.Galvanizing(hotdipzinc)isthemostcommonhotdipcoating.Waterisusedforrinsesfollowingprecleaningandsometimesforquenchingaftercoating.Thesewastewaterscancontributetothecommonmetalswastetype.


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UnitOperations33. Sputtering

34. VaporPlating35. ThermalInfusion

TABLE3.1.METALFINISHINGCATEGORYUNITOPERATIONS(Continued)SummaryDescriptionofUnitOperationsThisoperationistheprocessofcoveringametallicornon-metallicworkpiecewiththinfilmsofmetal.Thesurfacetobecoatedisbombardedwithpositiveionsinagasdischargetube,whichisevacuatedtoalowpressure.Thisoperationistheprocessofdecompositionofametalorcompounduponaheatedsurfacebyreductionordecompositionofavolatilecompoundatatemperaturebelowthemeltingpointofeitherthedepositorthebasismaterial.Thisoperationistheprocessofapplyingafusedzinc,cadmium,orothermetalcoatingtoaferrousworkpiecebyinbuingthesurfaceoftheworkpiecewithmetalpowderordustinthepresenceofheat.

36. SaltBathDescaling

37. SolventDegreasing

Thisoperationistheprocessofremovingsurfaceoxidesorscalefromaworkpiecebyimmersionoftheworkpieceinamoltensaltbathorahotsaltsolution.Moltensaltbathsareusedtoremoveoxidesfromstainlesssteelsandothercorrosion-resistantalloys.Thesebathscontainmoltensalts,causticsoda,sodiumhydrideandchemicaladditives.Thesecontaminants(andasmallamountofbasematerialandoils)enterwastewaterstreamsthroughrinsing,spills,leaks,batchdumpsofprocesssolutions,andimproperhandlingofsludgeproducedbytheprocess.Wastewatersproducedbysaltbathdescalingcontributetothecommonmetalsandoilywastetypes.Thisoperationisaprocessforremovingoilsandgreasefromthesurfaceofaworkpiecebytheuseoforganicsolventssuchasaliphaticpetroleums,aromatics,oxygenatedhydrocarbons,halogenatedhydrocarbons,andcombinationsoftheseclassesofsolvents.Thesepollutantscanenterwastewaterstreamsandcontributetothetoxicorganicwastetype.


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UnitOperations38. PaintStripping

39. Painting

TABLE3.1.METALFINISHINGCATEGORYUNITOPERATIONS(Continued)SummaryDescriptionofUnitOperationsThisoperationistheprocessofremovinganorganiccoatingfromaworkpiece. Thestrippingofsuchcoatingsisusuallyperformedwithcaustic,acid,solvent,ormoltensalt.Thestrippingwastescancontainanyoftheconstituentsofthepaintbeingremoved,aswellasasmallamountofthebasismaterialbeneaththepaintandtheconstitutentsofthestrippingsolution.Wastesareprimarilygeneratedbyrinsingandcanalsocontainsmallamountsofemulsifiedoils.Wastesproducedbelongtothecommonmetalsandoilywastetypesandmaycontaintoxicorganics.Thisoperationistheprocessofapplyinganorganiccoatingtoaworkpiece.

40. ElectrostaticPainting41. Electropainting

42. VacuumMetalizing43. Assembly

Thisoperationinvolvestheapplicationofelectrostaticallychargedpaintparticlestoanoppositelychargedworkpiecefollowedbythermalfusingofthepaintparticlestoformacohesivepaintfilm.Thisoperationistheprocessofcoatingaworkpiecebyeithermakingitanodicorcathodicinabaththatisgenerallyanaqueousemulsionofthecoatingmaterial.Electropaintingisusedprimarilyforprimercoatsbecauseitgivesafairlythick,highlyuniform,corrosionresistantcoatinginrelativelylittletime.Ultrafiltrationisusedinconnectionwithelectropaintingtoconcentratepaintsolids.Wastewatersfromtheseunitoperationscancontributetothecommonmetals,hexavalentchromium,andsolventwastetypes.Thisoperationistheprocessofcoatingaworkpiecewithmetalbyflashheatingmetalvaporinahigh-vacuumchambercontainingtheworkpiece.Thevaporcondensesonallexposedsurfaces.Thisoperationinvolvesthefittingtogetherofpreviouslymanufactured partsorcomponentsintoacompletemachine,unitofamachine,orstructure.


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UnitOperations44. Calibration

45. Testing

TABLE3.1.METALFINISHINGCATEGORYUNITOPERATIONS(Continued)SummaryDescriptionofUnitOperationsThisoperationinvolvestheapplicationofthermal,electrical,ormechanicalenergytosetorestablishreferencepointsforacomponentorcompleteassembly.'Thisoperationinvolvestheapplicationofthermal,electrical,ormechanicalenergytodeterminethesuitabilityorfunctionalityofacomponentorcompleteassembly.Leaktesting,finalwashing(automobiles,etc.),andtestareawashdownsenterwastestreamsandmaycontainoilsandfluidsusedattestingstationsaswellasheavymetalcontaminationderivedfromthecomponentbeingtested.Thesewastewaterscancontributetothecommonmetalsandoilywastetypes.

46. MechanicalPlating Thisoperationistheprocessofdepositingmetalcoatingsonaworkpieceviatheuseofatumblingbarrel,metalpowder,andusuallyglassbeadsfortheimpactionmedia. Theoperationissubjecttothesamecleaningandrinsingoperationsthatareappliedbeforeandaftertheelectroplatingoperation.

Note: UnitOperations1through6areconsideredtobecoreoperations. Ifafacilitydoesnotperformatleastoneofthesesixelectroplatingoperations,itisnotsubjecttotheMetalFinishingregulation.


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TABLE3.2POTENTIALWASTEWATERPOLLUTANTSGENERATEDBYMET ALFINISHING

UNITOPERATIONSHexavalent Toxic Zero

Unit Operations Metals Chromium Cyanide Oils Organics Discharge1. Electroplating X X X X2. ElectrolessPlating X X X3. Anodizing X X X4. ConversionCoating X X X X5. Etching(ChemicalMilling) X X X X6. PrintedCircuitBoardMan ufacturing X X7. Cleaning X X X X X8. Machining X X9. Grinding X X10. Polishing X X11. BarrelFinishing(Tumbling) X X X X12. Burnishing X X X13. ImpactDeformation X X14. PressureDeformation X X15. Shearing X X16. HeatTreating X X X17. ThermalCutting X 18. Welding X 19. Brazing X 20. Soldering X21. FlameSpraying X22. SandBlasting X23. OtherAbrasiv eJetMac hining X 24. ElectricDischargeMachining X X25. ElectrochemicalMachining X X X26. ElectronBeamMachini ng 27. LaserBeamMachining28. PlasmaArcMachining


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TABLE3.2POTENTIALWASTEWATERPOLLUTANTSGENERATEDBYMETALFINISHING

UNITOPERATIONS

Hexavalent Toxic ZeroUnit Operations Metals Chromium Cyanide Oils Organics Discharge29. UltrasonicMachining X30. Sintering X31. Laminating X32. HotDipCoating X33. Sputtering X34. VaporPlating X35. ThermalInfusion X36. SaltBathDescaling X X37. SolventDegreasing X X X 38. PaintStripping X X X39. Painting X X40. ElectrostaticPainting X X X41. Electropainting X X42. VacuumMetalizing X43. Assembly X X X44. Calibration X45. Testing X46. MechanicalPlating X X


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Incertaincases,anotherCategoricalPretreatmentStandardmayalsocoverwastewaterdischargesfrommetalfinishingoperations. Inthesesituations,themorespecificstandardswillapplytothosemetalfinishingwastestreamswhichappeartobecoveredbybothstandards. ThefollowingregulationstakeprecedenceovertheMetalFinishingregulation.

- NonferrousSmeltingandRefining(40CFRPart421)- CoilCoating(40CFRPart465)- PorcelainEnameling(40CFRPart466)

BatteryManufacturing(40CFRPart461)- IronandSteelManufacturing(40CFRPart420)- MetalCastingFoundries(40CFRPart464)- AluminumForming(40CFRPart467)

CopperForming(40CFRPart468)PlasticMoldingandForming(40CFRPart463)- ElectricalandElectronicComponents(40CFRPart469)- NonferrousForming(40CFRPart471)Forexample, ifaplantperformsacleaningandphosphatecoating

operationinpreparationforpaintingandalsoperformscleaning, pickling,immersioncoating,andchemicalcoatingaspartofaporcelainenamelingprocess, thentheMetalFinishingPSESapplytothedischargefromthecleaningandphosphatecoatingoperation,whilethePorcelainEnamelingPSESapplytothedischargefromapplicationoftheporcelainenamel,andalsothepreparatoryoperationsofcleaning,pickling,immersionplating,andchemicalcoatingoperation. Normally,themetalpreparationoperations(cleaning,pickling, immersionplating,andchemicalcoating)wouldbesubjecttotheMetalFinishingregulation. However,becausethePorcelainEnamelingregulationsspecificallyincludethoseoperationsperformedinpreparationfortheporcelainenamelingoperation,thePorcelainEnamelingregulationtakesprecedenceforthosewastestreams(SeeFigure3.1).3.3 PRETREATMENTSTANDARDSFORTHEMETALFINISHINGCATEGORY

TheMetalFinishingStandards(40CFRPart433)establishpretreatmentstandardsfornewandexistingfacilitiesperformingelectroplatingandother

3-14


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MetalFinishingProcess PorcelainEnameling

WastewatertoDischargeThesefouroperationsarenormallysubjecttotheMetalFinishingregulation;however,inthiscase,theyareperformedimmediatelypriortoaporcelainenamelingoperation. ThesetypesofoperationswereincludedaspartofthedatabaseusedtodevelopthePorcelainEnamelingregulations,thus, inthissituation, theyaresubjecttothePorcelainEnamelingregulation.Wastestream issubjecttoPart433ifdischarged. Wastestream (B) issubjecttoPart466ifdischarged. Ifthewastestreamsarecombinedbeforedischarge,thecombineddischarge (A+B)issubjecttothecombinedwaste-streamformula.

FIGURE3.1SCHEMATICSHOWINGEXAMPLEOFOVERLAPCOVERAGEOFCATEGORICAL

STANDARDSATINTEGRATEDFACILITIES

3-15


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metalfinishingoperations. ThesestandardsareBAT-equivalentandrepresentthebestavailabletechnologyeconomicallyachievable. Allexistingindirectdischargingelectroplatingfacilities(exceptjobshopelectroplatersandIPCBMs)mustfirstcomplywiththeElectroplating(Part413)andthenwiththeMetalFinishing(Part433)regulations. AnotherexceptioniscontinuousstripelectroplatingatIronandSteelMillswhichissubjectonlytotheMetalFinishingregulation;thisunitoperationisnotsubjecttotheElectroplatingregulation. Thelimitsapplyuniformlytodischargesfromallelectroplatingandothermetalfinishingoperations. Theuniformityinstandardsmeetsindustryrequestsforequivalentlimitsforprocesslinesoftenfoundtogether. TheMetalFinishingStandardsalsoreducetheneedtousetheCombinedWastestreamFormula. NoproductionbasedstandardsweredevelopedfortheMetalFinishing(Part433)Regulation. TheMetalFinishingstandardsarebased

onthe99thpercentileofexpectedvariationsfromobservedlong-termunconstructedaverages. Theyincludedailymaximumsandmaximummonthly

(statisticallybasedon10samplespermonth)averageconcentrationlimitations. ThePSESandPSNSlimitationsformetalfinishingfacilitiesarepresentedinTable3.3. Ifaplantintendstoconsistentlycomplywiththeregulatorylimititshouldusethe longtermconcentration averageasthebasis for design and operation. Table3.4presentslong-termconcentrationaverageswhichwerefoundtobeattainablebythetechnologyEPAassessed.Theyarepresentedasguidancetodischargersandcontrolauthorities.

Thepretreatmentstandardsfornewsources(PSNS)applytoelectroplatingandmetalfinishingfacilitieswhichbegantheiroperationafterAugust31,1982, thedateoftheproposedregulation. ThePSNSformetalfinishingfacilitiesarethesameasthoseforexistingsources,withtheexceptionthatcadmiummustbecontrolledmorestringently.3.4 POLLUTANTSEXCLUDEDFROMREGULATION

TheEPAexcludedfromregulation7ofthe126toxicpollutantswhicharegivenpriorityconsideration(antimony,arsenic,asbestos,beryllium,mercury,selenium,andthallium). Thesepollutantsarefoundinonlyasmallnumberofsourcesandareeffectivelycontrolledbythetechnologiesonwhichthelimitsarebased.

3-16


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TABLE3.3

PRETREATMENTSTANDARDSFORTHEMETALFINISHINGCATEGORY40CFRPART433

PRETREATMENTSTANDARDSFOREXISTINGSOURCES(PSES)PollutantCadimium(T)Chromium(T)Copper(T)Lead(T)Nickel(T)Silver(T)Zinc(T)Cyanide,totalTotalToxicOrganics(interim)TotalToxicOrganics(final)Alternativetototalcyanide:Cyanide,amenabletochlorination

DailyMaximum(mg/1)

0.692.773.380.693.980.43

6120

4.572.130.86

MaximumMonthlyAverage(mg/1)

0.261.712.070.432.380.241.480.65

0.32

PRETREATMENTSTANDARDSFORNEWSOURCES(PSNS)PollutantCadmium(T)Chromium(T)Copper(T)Lead(T)Nickel(T)Silver(T)Zinc(T)Cyanide,totalTotalToxicOrganicsAlternativetototalcyanide:Cyanide,amenabletochlorination

DailyMaximum(mg/1)

0.112.773.380.693.980.432.611.20 2.130.86

MaximumMonthlyAverage(mg/1)

0.071.712.070.432.380.241.480.65

0.32

Note:NomaximummonthlyaverageTTOconcentrationregulated.(T)=total.

3-17


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TABLE3.4

LONGTERMCONCENTRATIONAVERAGES

Cadmium(T)fornewsourcesis0.058mg/1.

3-18

LongTermConcentrationAverageMilligramsPerLiter

PollutantofPollutantProperty (mg/1)Cadmium(T) 0.13Chromium(T) 0.572Copper(T) 0.815Lead(T) 0.20Nickel(T) 0.942SilverOT) 0.096Zinc(T) 0.549Cyanide(T) 0.18Cyanide,A 0.06TTO(rawwater) 1.08TTO(effluent) 0.434


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3.5 COMPLIANCEDATESAllindustriessubjecttotheElectroplatingStandards(exceptjobshop

electroplatersandIPCBMs)willhavetocomplywiththeMetalFinishing(Part433)regulations. ThecontroloftoxicorganicsisanadditionalrequirementforfacilitiescurrentlyunderElectroplatingPSES. Compliancewasfoundtobeachievablewithgoodmanagementpractices(recoveringsolventsforcontracthaulingorreclamation)andatlowcosts. AninterimTTOlimitbasedsolelyonachievingcompliancewithgoodhousekeepingpracticesbeforeend-of-pipetreatmentisrequiredtobein-place,andwasestablishedtopreventorganicsfrombeingcompletelyuncontrolledduringthetimebeforefinalcompliance.TheMetalFinishingcompliancedatesareshowninTable3.5.3.6 ALTERNATIVECYANIDELIMITATION

Analternativecyanidelimitisavailableforfacilitieswithsignificantformsofcomplexedcyanide(i.e.ironcyanides)notcontrollablebythetechnologybasis. Thesecomplexedformsarelesstoxicbutmaystillundergotransformationtothemoretoxicfreecyanideforminthewaterways. Beforeallowingthecyanideamenablealternative,theControlAuthorityshouldconsiderpossiblewaterqualityimpactsduetothedischargeofcyanide. Complexcyanidescanbecontrolledbytheadditionofferroussulfatetotheprecipitation/clarificationsystem.

3-19


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TABLE3.5COMPLIANCEDATESFORMETALFINISHINGPRETREATMENTSTANDARDS

40CFRPART433PollutantParameter ExistingSourcesCapitives_ NewSourcesInterimTTO1 June30,1984Metals,Cyanide,andFinalTTO February15,1986 oncommencementofdischarge1 . TTO=TotalToxicOrganics"July10, 1985forplantscoveredby40CFRPart420,IronandSteel

3-20


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4. TREATMENTTECHNOLOGIESThetreatmenttechnologiesdescribedinthissectionarecurrentlyused

bymetalfinishers/electroplaterstoremoveorrecoverwastewaterpollutantsnormallygenerated. Figure4.1isanexampleofthecurrenttechnologycommonlyusedfortreatmentofmetalfinishingwastewater. Asindicated,waste-streamsegregationallowstherecoveryofpreciousmetals,thereductionofhexavalentchromium,thedestructionofcyanide,andtheremovalandrecoveryofoilspriortotheremovalofcommonmetals. Wastestreamsegregationcanreducetheflowofwastewatertothetreatmentsystemand,accordingly,reducethecostoftreatment.4.1 TREATMENTOFCOMMONMETALSWASTE

Thetechnologybasisforthepretreatmentstandardsconsistsofhydroxideprecipitationfollowedbysedimentation. Hydroxideprecipitationisusedtoprecipitatedissolvedmetalsbychemicaladditionsothattheycanberemovedbyphysicalmeanssuchassedimentationorfiltration. Hexavalentchromiumisnotremovedbythistreatmentsystemandcyanidewillinterferewiththesystem'sabilitytoremovethe'dissolvedmetals. Theserawwastetypesshouldbetreatedbeforeenteringthissystem.

TheEPAalsoconsideredbutrejectedtheadditionoffiltrationtotheselectedtechnologybasistoremoveadditionalsuspendedsolids(suchasmetalhydroxides)whichdidnotsettleoutintheclarifier. Itmaybeappropriateincaseswheretherearespecificambientwaterqualityproblems. Thetechnologybasistreatmentsystemplusin-plantcadmiumcontrols(suchasevaporativerecoveryandionexchange)wasusedasthetechnologybasisfornewsourcepretreatmentstandards.

Alternativetreatmentmethodsforcommonmetalsremoval, tobeusedinconjunctionwithorinplaceofthepreceedingmethods,includepeatadsorption,insolublestarchxanthatefiltration,sulfideprecipitation,flotation,andmembranefiltration.

4-1


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Ccaplexed ; .e t a l s ! tetal

j |eatn ct on

u

Ma nufa c t uri ngFacilityRawWatt*Sourc c s ToxicOrganlcs

RawWasteDischarge(TreataentSystea

Influent) OowcnNetala

MasteTreatment(I fApplicable) I OilyMaate!Reoovali ChmiuaiReduction Cyanide 1rf .HetalsReaoval

TreatedBffluent 5

withoutCyanideRawWaste

(OoonNetals)Netals

ReaovalTreated

Effluent

PinalTreatedEffluent

' I1_1Ir

HauledOrReclaiMd

HauledOrReclaiaed

FIGURE4.1WASTEWATERTREATMENTSCHEMATIC

NorrnlRouteOptionaltoute

HotelDischargefroaprecioittwtalsleoowetyaaybehauledinalternativeways,dependingonthe recweryMethodinuse.


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A.2 TREATMENTOFCOMPLEXEDMETALWASTES

Complexedmetalsaretiedupbychemicals(complexingagentssuchasammoniaandcitricacid)whichpreventthemetalsfromsettlingoutofsolution. Complexedmetalwastesareaproductofelectrolessplating,immersionplating,etchingandprintedcircuitboardmanufacturing. Metalstiedupinsolutioncounteractthe-conventionalprecipitationtechnique. Asaresult,segregatedtreatmentofthecomplexedmetalwastesisrecommended.

HighpHprecipitationisaprocessinvolvingtheadditionofchemicalswhichdrasticallyincreasethepHtoaround12,promptingashiftinthecomplexdissociationequilibriumandresultingintheproductionoffreemetalions. Themetalionscanthenbeprecipitatedbyavailablehydroxideionsandremovedbysedimentation.

ThechemicalreductionprocessaddschemicalstolowerthepHofthewastestream(tobreakupthevariousmetalcomplexes)followedbytheadditionofareducingagenttoreducethemetalstoanoxidationstatewhichpermitsprecipitationofthemetals. AdditionalchemicalstoraisethepHarethenaddedtoformmetallicprecipitateswhichsettleoutofsolution. Mediaormembranefiltrationisanalternatemethodtosedimentationforsolidsremoval.

Modifyingthehydroxideprecipitationprocessbysubstitutingsulfideprecipitationcanimprovesystemperformanceintheremovalofcomplexedheavymetals. Theferroussulfatetechniqueiscapableofachievinglowmetalsolubilitiesinspiteofthepresenceofcertaincomplexingagents.A.3 TREATMENTOFPRECIOUSMETALSWASTES

Treatmentofpreciousmetalsconsistsofthetechnologybasisforcommonmetalswastespluspreciousmetalsrecoveryincludingevaporation,ionexchange,andelectrolyticrecovery. Evaporationisusedtorecoverpreciousmetalsbyboilingoffthewaterportionofthepreciousmetalsolutionandremovingthemetal.

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Ionexchangeistheprocessinwhichions,heldbyelectrostaticforcestochargedfunctionalgroupsonthesurfaceofanionexchangeresin,areexchangedforionsofsimilarchargefromthesolutioninwhichtheresinisimmersed. Ionexchangeiscommonlyusedforpreciousmetalrecovery,especially

gold.

Electrolyticrecoveryisparticularlyapplicabletopreciousmetalsrecoverybecausethevaluablepreciousmetalsofferafasterpaybackonequipmentandenergycosts. Theprocessconsistsofadragoutrinseaftertheplatingstepandanofflineelectrolyticrecoverytank.4.4 TREATMENTOFHEXAVALENTCHROMIUM

Thetreatmentofhexavalentchromiuminvolvesreducinghexavalentchromiumtotrivalentchromiumandremovalwithaconventionalprecipitation-solidsremovalsystem. Reduced(trivalent)chromiumisabletobeseparatedfromsolutioninconjunctionwithothermetallicsaltsbyalkalineprecipitation. Inmostcases,gaseoussulfurdioxideisusedasthereducingagentinthereductionofhexavalentchromiumwhichenablesthetrivalentchromiumtobeseparatedfromsolutionbyalkalineprecipitation.

Alternativehexavalentchromiumtreatmenttechniquesincludeelectrochemicalchromiumreduction,regeneration,evaporation,andionexchange.4.5 TREATMENTOFCYANIDEWASTES

Treatmentofcyanideisalmostexclusivelyperformedbyalkalinechlorlnationwhichfocusesuponoxidizingthecyanidewhichisamenabletochlorination. Thedestructionofcyanideresultsinproductsofcarbondioxideandnitrogen. Additionally,ferroussulfatemaybeusedtoprecipitatecomplexedcyanides.

Alternativetreatmenttechniquesforthedestructionofcyanideincludeoxidationbyozone,ozonewithultravioletradiation,hydrogenperoxide,andelectrolyticoxidation.

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4.6 TREATMENTOFOILYWASTESTechniquescommonlyusedbyelectrolatersandmetalfinisherstoremove

oilsincludeskimming,coalescing,emulsionbreaking,flotation,centrifu-gation,ultrafiltration,andreverseosmosis. Treatmentofoilywastesismostefficientandcosteffectiveifoilsaresegregatedfromotherwastesandtreatedseparately. Theprocessofseparationvariesdependingonthetypeofoilinvolved.k.l IN-PLANTCONTROLOFTOXICORGANICS

Theprimarycontroltechnologyfortoxicorganicsisproperstorageofconcentratedtoxicorganicswithoutdischargingdirectlyintowastestreamsandsegregationfromotherwastesthatwillenterthewastetreatmentsystem.Spentdegreasingsolventsmaybesegregatedfromotherwastesbyprovidingandidentifyingthenecessarystoragecontainers,trainingpersonnelintheuseofthetechniques,andholdingperiodiccheck-upstoensurethatpropersegregationisoccurring. Theseparatewastesolventscanthenberecoveredon-siteorcontracthauled.

Usingcleaningtechniquesthatrequirenosolventswilleliminateorreducethequantityoftoxicorganicsfoundinwastewater. Cleaningtechniquesmayincludewiping,immersion,spraytechniquesusingwater,alkalineandacidmixtures,andsolventemulsions.

Toxicorganicsthatenterthewastestreamscanberemovedbytreatmenttechnologiesusedforthecontrolofotherpollutants. Toxicorganicstendtobemoresolubleinoilandgreasethaninwater. Thusremovalofoilandgreasewillreducethedischargeoftoxicorganics. Otherpossiblemechanismsforremovalincludeadsorption,settling,andvolatilization,whichcanoccurduringtreatmentofmetals,cyanide,andoilandgrease.

SpecifictreatmenttechnologieswhicharenotpartofthetechnologybasisoftheregulationbutareapplicableforthetreatmentofTTOincludecarbonadsorptionandreverseosmosis,resinadsorption,ozonation,chemicaloxidation,andaerobicdecomposition.

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4.8 TREATMENTOFSLUDGESSludgesarecreatedbywastetreatmenttechnologieswhichremovesolids

fromwastewater. Sludgethickeningisusedtoconcentratedilutesludgesbyamechanicaldevicesuchasavacuumfilterorcentrifuge. Doublingthesolidscontentreducescapitalandoperatingcostsandreducescostsforhauling.Pressurefiltrationisachievedbypumpingtheliquidthroughafiltermaterialwhichisimpenetrabletothesolidphase. Sludgebeddryingisemployedtoreducethewatercontentofsludgessothattheycanbemechanicallycollectedforremoval. Sludgemaythenbetransportedtolandfillsorincinerated.

Additionalremovalmethodsforindustrialwastesludgesincludechemicalcontainment,

encapsulation,

fixation,

andthermalconversion.4.9 IN-PROCESSCONTROLTECHNOLOGIES

In-processcontroltechniqueshavebeendevelopedandarebeingutilizedbyelectroplatersandmetalfinishers. Thesetechniquesdealwithreducingwaterusage,reducingdragoutofpollutantsandefficienthandlingofprocesswastesandinclude:

FlowreductionthroughefficientrinsingCountercurrentandstaticrinsingProcessbathconservation

- WasteoilsegregationProcessbathsegregationProcessmodificationCuttingfluidcleaning

- Integratedwastetreatment- GoodhousekeepingReducingthewaterusageatmetalfinishingfacilitiesisthemost

importantcontrolandresultsinreducedpollutantdischargeandconsequentlyreducedcostsforwastewatertreatment. Itisestimatedthatrinsestepsconsumemostofthewaterusedatmetalfinishingfacilities. Therefore,efficientrinsesystemswouldleadtothegreatestwaterusereductions.Severalrinsingtechniquesarecurrentlyusedatmetalfinishingfacilities.

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Ofthese,thecountercurrentrinseprovidesforthemostefficientwaterusage,andconsistsofonlyonefreshwaterfeedintroducedinthelasttank.Thedeadorstaticrinseisapplicableforinitialrinsingaftermetalplatingandallowsforeasiermetalsrecoveryandlowerwaterusage.

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5. REQUIREMENTSOFTHEGENERALPRETREATMENTREGULATIONS5.1 INTRODUCTION

ThissectionprovidesabriefoverviewoftheGeneralPretreatmentRegulationsandidentifiesthoseprovisionsoftheRegulationswhichhaveadirectbearingontheapplicationandenforcementofCategoricalPretreatmentStandardsfortheElectroplatingandMetalFinishingcategory.

TheGeneralPretreatmentRegulationsforExistingandNewSources(40CFRPart403)establishtheframeworkandresponsibilitiesforimplementationoftheNationalPretreatmentProgram., Theeffectof40CFRPart403isessentiallythree-fold. First,theGeneralPretreatmentRegulationsestablishgeneralandspecificdischargeprohibitionsasrequiredbySections307(b)and(c)oftheCleanWaterAct. ThegeneralandspecificprohibitionsaredescribedinSection403.5ofthePretreatmentRegulationsandapplytoallnondomesticsourcesintroducingpollutantsintoaPOTWwhetherornotthesourceissubjecttoCategoricalPretreatmentStandards.

Second,theGeneralPretreatmentRegulationsestablishanadministrativemechanismtoensurethatNationalPretreatmentStandards(ProhibitedDischargeStandardsandCategoricalPretreatmentStandards)areappliedandenforceduponindustrialusers. Approximately1,700POTWsarerequiredtodevelopalocallyrunpretreatmentprogramtoensurethatnon-domesticuserscomplywithapplicablepretreatmentstandardsandrequirements.

Third,andmostimportantlyforthepurposesofthisguidancemanual,theGeneralPretreatmentRegulationscontainprovisionsrelatingdirectlytotheimplementationandenforcementoftheCategoricalPretreatmentStandards.Reportingrequirements,locallimits,monitoringorsamplingrequirements,andcategory

determination

provisions

are

discussed.

POTW

representatives

should

referto40CFRPart403forspecificlanguageandrequirementswhereappropriate.

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5.2 CATEGORYDETERMINATIONREQUESTAnexistingindustrialuser(lU)oritsPOTWmayrequestwritten

certificationfromEPAorthedelegatedStatespecifyingwhetherornottheindustrialuserfallswithinaparticularindustrycategoryorsubcategoryandissubjecttoacategoricalpretreatraentstandard. Althoughthedeadlineforsubmittingacategorydeterminationrequestbyexistingindustrialuserssubjecttotheelectroplatingandmetalfinishingcategoricalpretreatmentstandardshaspassed,anewindustrialuseroritsPOTWmayrequestthiscertificationforacategorydeterminationanytimepriortocommencingitsdischarge. ThecontentsofacategorydeterminationrequestandproceduresforreviewarepresentedinSection403.6(a)oftheGeneralPretreatmentRegulations.5.3 MONITORINGANDREPORTINGREQUIREMENTSOFTHEGENERALPRETREATMENTREGULATIONS

InadditiontotherequirementscontainedintheElectroplatingandMetalFinishingCategoricalPretreatmentStandards,industrialuserssubjecttotheseStandardsmustfulfillthereportingrequirementscontainedinSection403.12oftheGeneralPretreatmentRegulations. Theserequirementsincludethesubmissionofbaselinemonitoringreports, complianceschedules,compliancereports(initialandperiodic),noticesofslugloading,andrecordkeepingrequirements. Eachofthesereportingrequirementsisbrieflysummarizedbelow.5.3.1 Baseline Monitoring Reports

AllindustrialuserssubjecttoCategoricalPretreatmentStandardsmustsubmitabaselinemonitoringreport(BMR)totheControlAuthority. ThepurposeoftheBMRistoprovideinformationtotheControlAuthoritytodocumenttheindustrialuser'scurrentcompliancestatuswithaCategoricalPretreatmentStandard. TheControlAuthorityisdefinedasthePOTWifithasanapprovedpretreatmentprogram,otherwisetheBMRwillbesubmittedtotheState(iftheStatehasanapprovedStatePretreatmentProgram)ortotheEPARegion. AdditionalguidanceonBMRreportingisavailablefromtheEPARegionalPretreatmentCoordinator.

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BMRDueDatesSection403.12(b)requiresthatBMRsbesubmittedtotheControl

Authoritywithin180daysaftertheeffectivedateofaCategoricalPretreat-mentStandardor180

daysafterthefinaladministrativedecisionmade

upona

categorydeterminationrequest[403.6(a)(4)],whicheverislater. Table5.1showstherespectiveduedatesforelectroplatingandmetalfinishingBMRs.

BMRContentABMRmustcontainthefollowinginformationasrequiredbySection

403.12(b).1. Nameandaddressofthefacility,includingnamesofoperator(s)and

owner(s).2. Listofallenvironmentalcontrolpermitsheldbyorforthe

facility.3. Briefdescriptionofthenature,averageproductionrateandSIC"code

foreachoftheoperation(s)conducted,includingaschematicprocessdiagramwhichindicatespointsofdischargefromtheregulatedprocessestothePOTW.

4. Flowmeasurementinformationforregulatedprocessstreamsdischargedtothemunicipalsystem. Flowmeasurementsofotherwastestreamswillbenecessaryifapplicationofthecombinedwastestreamformulaisnecessary.

5. Identificationofthepretreatmentstandardsapplicabletoeachregulatedprocessandresultsofmeasurementsofpollutantconcentrationsand/ormass. Allsamplesmustberepresentativeofdailyoperationsandresultsreportedmustincludevaluesfordailymaximumandaverageconcentration(ormass,whererequired). Wheretheflowoftheregulatedstreambeingsampledislessthanorequalto250,000gallonsperday,theindustrialusermusttakethreesampleswithinatwoweekperiod. Wheretheflowofthestreamisgreaterthan250,000gallonsperday,theindustrialusermusttakesixsampleswithinatwoweekperiod. Ifsamplescannotbetakenimmediatelydownstreamfromtheregulatedprocessandotherwastewatersaremixedwiththeregulatedprocess, theindustrialusershouldmeasureflowsandconcentrationsoftheotherwastestreamssufficienttoallowuseofthecombinedwastestreamformula. RequirementsfordemonstratingcompliancewithTTOstandardsarediscussedinSection5.4.1.

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TABLE5.1DUEDATESFORSUBMISSIONOFBASELINEMONITORINGREPORTS

ExistingIndirectDischargersNon-integratedJobShops&

IPCBM'sIntegratedJobShopsIPCBM's Non-integratedCaptives IntegratedCaptives

Electroplating(Part413)

MetalsandCyanideElectroplating(Part413)TTOMetalFinishing(Part433)

Metals,Cyanide,andTTO

September12,1981June25,1983September12,1981June25,1983February24,1984February24,1984

February24,1984February24,1984Note: Ifarequestforacategorydeterminationhasbeenmade,thentheBMRisdue180days

afterthefinaldecisiononthecategorydetermination.

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6. StatementofcertificationconcerningcomplianceornoncompliancewiththePretreatmentStandards.

7. Ifnotincompliance, acomplianceschedulemustbesubmittedwith theBMRthatdescribestheactionstheuserwilltakeandatimetableforcompletingthoseactionstoachievecompliancewiththestandard.This

complianceschedulemustcontain

specificincrementsof

progress

intheformofdatesforthecommencementandcompletionofmajorevents,however,noincrementofthescheduleshallexceed9months.Within14daysofeachcompletiondateintheschedule, theindus trialusershallsubmitaprogressreporttotheControlAuthorityindicatingwhetherornotitcompliedwiththeIncrementofprogress tobemetonsuchdate,and, ifnot, thedateonwhichitexpectstocomplywiththisincrementofprogressandthestepsbeingtakentoreturntotheschedule.

BMRReportingofToxicOrganlcs SincepromulgationoftheMetalFinishingpretreatmentstandards, somequestionshavebeenraisedregardingBMRreportingoftotaltoxicorganics

(TTO). BMRsamplingrequirementsclearlyapplytoallregulatedmetals.However, sincemonitoringfortoxicorganicscanbeexpensive,BMRsamplingandanalysisforTTOwillonlyberequiredforthoseorganics "whichwouldreasonablybeexpectedtobepresent"intheindustrialuser'seffluent [Section413.03(c)]. Forroutinecompliancemonitoring,notBMRmonitoring, theregulationsallowforthelUtocertifythattheregulatedtoxicorganicsare notusedatthefacilityortopresentaplandemonstratingappropriatecontrolstopreventorganiccompoundsfromenteringthewastestream. Evenifthe industrialuserexpectstousethecertificationproceduretodemonstrateregularcompliancewiththeTTOlimitation, theusermuststillsampleandanalyzeforanytoxicorganic"reasonablyexpectedtobepresent"forthe purposesofthebaselinemonitoringreport. Ifnotoxicorganicsareusedorexpectedtobedischarged, thennoTTOmonitoringisrequiredfortheBMR.5.3.2 ReportonCompliance

Within90daysafterthecompliancedatefortheElectroplatingandMetalFinishingPretreatmentStandardsorinthecaseofaNewSourcefollowingcommencementoftheintroductionofwastewaterintothePOTW,anyindustrialusersubjecttotheStandardsmustsubmittotheControlAuthoritya"reportoncompliance"thatstateswhetherornotapplicablepretreatmentstandards

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arebeingmetonaconsistentbasis. Thereportmustindicatethenatureandconcentrationofallregulatedpollutantsinthefacility'sregulatedprocesswastestreams; theaverageandmaximumdailyflowsoftheregulatedstreams;andastatementofwhethercomplianceisconsistentlybeingachieved,andifnot,whatadditionaloperationandmaintenanceand/orpretreatmentisnecessarytoachievecompliance. See40CFR403.12(d).5.3.3 Periodic ReportsonContinued Compliance

UnlessrequiredmorefrequentlybytheControlAuthority,allindustrialuserssubjecttotheElectroplatingandMetalFinishingCategoricalPretreatmentStandardsmustsubmitabiannual"periodiccompliancereport"duringthemonthsofJuneandDecember. ThereportshallindicatetheprecisenatureandconcentrationsoftheregulatedpollutantsinitsdischargetothePOTW,theaverageandmaximumdailyflowratesofthefacility,themethodsusedbytheindirectdischargertosampleandanalyzethedata,andacertificationthatthesemethodsconformedtothosemethodsoutlinedintheregulations. See40CFR403.12(e).5.3,4 Notice of Slug Loading

Section403.12(f)requiresindustrialuserstonotifythePOTWimmediatelyofanyslugloadingofanypollutant,includingoxygendemandingpollutants(BOD,etc.)releasedtothePOTWsystemataflowrateand/orpollutantconcentrationwhichwillcauseinterferencewiththePOTW.5.3.5 Monitoring and AnalysistoDemonstrate Continued Compliance

Section403.12(g)statesthatthefrequencyofmonitoringtodemonstratecontinuedcomplianceshallbeprescribedintheapplicablePretreatmentStandard. NeithertheElectroplatingnorMetalFinishingPretreatmentStandardestablishanymonitoringfrequency. Therefore,theappropriateControlAuthority

mustestablishthemonitoring

frequency

toadequately

demonstratethatindirectdischargerssubjecttothesepretreatmentstandardsareincompliancewiththeapplicablestandards. UnlessotherwisenotedintheappropriateparagraphofSection403.12,themonitoringfrequencyestablishedbytheControlAuthorityshallbeusedinthebaselinemonitoringreport(403.12(b)(5)),

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thereportoncompliancewithcategoricalpretreatmentstandarddeadline(403.12(d)),andtheperiodicreportsoncontinuedcompliance(403.12(e)).

Samplingandanalysisshallbeinaccordancewiththeproceduresestablishedin40CFRPart136andanyamendmentstoitorshallbeapprovedbyEPA. WhenPart136techniquesarenotavailableorareinappropriateforanypollutant,thensamplingandanalysisshallbeconductedinaccordancewithproceduresestablishedbythePOTWorusinganyvalidatedprocedure. However,allproceduresforsamplingandanalysisnotincludedinPart136mustbeapprovedbyEPA.5.3.6 Signatory RequirementsforIndustrialUserReports

Allreportssubmittedbyindustrialusers(BMR,InitialReportonCompliance,andPeriodicReports,etc.)must"besignedbyanauthorizedrepresentativeinaccordancewithSection403.12(k).5.3.7 Recordkeeping Requirements

AnyindustrialusersubjecttothereportingrequirementsoftheGeneralPretreatmentRegulationsshallmaintainrecordsofallinformationresultingfromanymonitoringactivitiesrequiredby403.12foraminimumofthreeyears[403.12(n)]. TheserecordsshallbeavailableforinspectionandcopyingbytheControlAuthority.5.4 SPECIALINDUSTRIALSELF-MONITORINGCONSIDERATIONS5.4.1 ToxicOrganicsCertification

InlieuofmonitoringforTTO,theControlAuthoritymayallowdischargerssubjecttoElectroplatingandMetalFinishingregulationstocertifythatnodumpingoftoxicorganicstothewastestreamhasoccurred. IncaseswheremonitoringtodetermineTTOcomplianceisnecessary,samplingandanalysisforTTOwillonlyberequiredforthoseorganics"whichwouldreasonablybeexpectedtobepresent"intheindustrialuser'seffluent[Section413.03(c)]. Whendischargersrequestthatnomonitoringberequired,theymustsubmitatoxicorganicmanagementplanthatspecifiesthetoxicorganiccompoundsused,themethodofdisposalused(insteadofdumpinginto

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wastestreams),andproceduresforassuringthattoxicorganicsdonotroutinelyspillorleakintowastewaterdischargedtothePOTW. Thiscertificationisaddedasacommenttothebaselinemonitoringreportaswellasperiodicreports.

AtoxicmanagementplanprovidesmethodsforthereductionoftoxicsineffluentsandassistsindustrialfacilitiesinachievingcompliancewithCategoricalPretreatmentStandards. Anexampleofatoxicorganicmanagementplanthatisrequiredwhenindustrialuserswishtocertifythatnodischargeoftoxicpollutantshasoccurredispresentedbelow.

Theplanhasthreebasicsteps:Step1-Processengineeringanalysisshouldconsistof:a. Anexaminationofpublishedreportsonthespecificindustry;b. Awaterflowdiagramtoidentifyallpossiblewastewatersources;c. Alistofrawmaterialsusedintheindustrialprocesses,including

chemicaladditives,watertreatmentchemicalsandcleaningagents,andthewastewaterstreamthateachmaterialpotentiallyenters;

d. Comparisonofthetoxicsfoundintheeffluentwiththelistofrawmaterialsandselectionofthemostprobablewastewatersource;

e. Evaluationofthetoxicsfoundintheeffluent,butnotontherawmaterialslistanddeterminationofthoseformedasreactionproductsorby-products;

f. Examinationofsourcessuchasequipmentcorrosionorrawmaterialsimpuritiescontributinginorganicpollutants.

Step2-Pollutantcontrolevaluationshouldbedeterminedonacase-by-casebasisandmayinclude:

a. Inplantprocessmodification,includingchemicalsubstitution,partialorcompleterecycling,reuse,neutralization,ionexchange,oroperationchanges.

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Step3-ToxicsreductionevaluationreportissubmittedtotheControlAuthorityandcontains:

a. Identificationofsource(s)ofpollutant(s).b. Controloptionsexplored.c. Effectivenessofcontroloptionsinmeetingeffluentlimits.d. Industrialuser'schoiceofoptionsandtheprojectedschedulefor

achievingnecessarycontrol.Incertaincases,theindustrialuserwillnotachievecompliancewith

theeffluentstandard. Inthesecases,additionalevaluationswillbenecessary.5.4.2 Self-Monitoring for Cyanide

ForfacilitiessubjecttoMetalFinishingregulations,self-monitoringforcyanidemustbeconductedaftercyanidetreatmentandbeforedilutionwithotherwastestreams. Alternatively,samplesmaybetakenofthefinaleffluentiftheplantlimitationsareadjustedbasedonthedilutionratioofthecyanidewastestreamflowtotheeffluentflow.5.5 APPLICATIONOFTHECOMBINEDWASTESTREAMFORMULA

OneprovisionoftheGeneralPretreatmentRegulationsthatwilloftenbenecessaryforPOTWsandindustriestoproperlymonitorandreportoncompliancewithCategoricalPretreatmentStandardsistheCombinedWastestreamFormula(CWF) [40CFR403,6(e)]. TheCWFisamechanismforcalculatingappropriatelimitationsspecifiedinapplicableregulationstoawastewaterinwhichprocesswastestreamsaremixedwithregulated,unregulatedordilutionstreams,therebyresultinginamixedeffluent. TheCWFisappliedtothemixedeffluenttoaccountforthepresenceoftheadditionalwastestreams.

ThefollowingdefinitionsandconditionsareimportanttotheproperuseoftheCWF,

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Definitions Regulated Process Wastestream-anindustrialprocesswastestream

regulatedbyNationalCategoricalPretreatmentStandards. UnregulatedProcessWastestream-anindustrialprocesswastestream

thatisnotregulatedbyacategoricalstandard.Note; Definitionsapplytoindividualpollutants. Awastestreamfroma

processmaybe"regulated"foronepollutantand"unregulated"foranother.

Dilute Wastestream-Boilerblowdown,sanitarywastewater,noncontactcoolingwaterorblowdovm,andParagraph8excludedwastestreamscontainingnoneoftheregulatedpollutantoronlytraceamountsofit.

Concentration-based Limit-alimitbasedontherelativestrengthofapollutantinawastestream,usuallyexpressedinmg/1(lb/gal).

Mass-based Limit-alimitationbasedontheactualquantityofapollutantinawastestream,usuallyexpressedinmg/someunitofproductionforagivenoperationsuchassquaremeter(lb/squarefootperoperation).

CWFConditionsToensureproperapplicationoftheCWF,thefollowingconditionsmustbe

metbyamunicipalityanditsindustries [40CFR403.6(e)]: AlternativedischargelimitsthatarecalculatedinplaceofaCategoricalPretreatmentStandardmustbeenforceableasCategorical

Standards. CalculationofalternativelimitsmustbeperformedbytheControl

Authority(POTW)orbytheindustrialuserwithwrittenpermissionfromthePOTW.

Alternativelimitsmustbeestablishedforallregulatedpollutantsineachoftheregulatedprocesses.

TheControlAuthorityand/ortheindustrialusermayusemass-basedlimitationsinplaceoftheconcentration-basedlimitations,whentheyareprovidedforbyagivenCategoricalPretreatmentStandardsuchaselectroplating,aslongasaprioragreementexistsbetweentheregulatedindustrialuserandthemunicipalitythatisreceivingthesewastes.

Bothdailymaximumandlong-termaverage(usuallymonthly)alternativelimitsmustbecalculatedforeachregulatedpollutant.

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Ifprocesschangesatanindustrywarrant,theControlAuthoritymayrecalculatethealternativelimitsatitsdiscretionorattherequestoftheindustrialuser. Thenewalternativelimitsmustbecalculatedandbecomeeffectivewithin30daysoftheprocesschange.TheControlAuthoritymayimposestricteralternativelimits,butmaynotimposealternativelimitsthatarelessstringentthanthecalculatedlimits.Acalculatedalternativelimitcannotbeusedifitisbelowtheanalyticaldetectionlimitforthatpollutant. Ifacalculatedlimitisbelowthedetectionlimit,thelUmusteither: 1)notcombinethedilutestreamsbeforetheyreachthecombinedtreatmentfacility,or2)segregateallwastestreamsentirely.ThecategoricalstandardsoftheregulatedwastestreamswhichareappliedtotheCWFmustbeconsistentintermsofthenumberofsamplesthestandardisbasedon. Electroplatingwastestreamsareregulatedbya-4-dayaveragestandardandarenotconsistentwithother

categoricalstandards

regulatedbyamaximum

monthlyaverage

(basedon10sampledays)standard. Accordingto40CFRPart413.04,ifanon-electroplatingwastestreamisregulatedbyamonthlyaveragestandardandIscombinedwithanelectroplatingwastestream,monthlystandardsratherthan4-dayaveragestandardsaretobeusedincalculatinganalternativelimitwiththeCWF. Also,iftwoelectroplatingwastestreamsregulatedunderdifferentsubcategoriesoftheelectroplatingregulationsarecombined,the4-daylimitsmaybeusedtocalculatethealternatelimits,unlessanadditionalwastestreamsubjecttomonthlystandardsisadded. Thefollowingequivalentmonthlyaverages(basedon10sampledayspermonth)havebeendevelopedforuseintheCWF;

EquivalentMonthlyPollutantCadmium(T)Chromium(T)Copper(T)Lead(T)Nickel(T)Zinc(T)Silver(T)TotalMetalsCyanide,ACyanide(T)

Average(m"g/l)0.633.562.440.372.382.370.636.262.370.87

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MonitoringRequirementsForIndustrialUsersUsingtheCWFSelf-monitoringrequirementsbyanIndustrialuserarenecessaryto

ensurecompliancewiththealternativecategoricallimit. BecauseneithertheMetalFinishingnorElectroplatingPretreatmentStandardsincludeself-monitoringrequirements, theControlAuthoritywillestablishminimumself-monitoringrequirements.

ApplicationoftheCWFTheactualcombinedwastestreamformulasarepresentedinTable5.2.

Tables5.3and5.4presentanexampleofhowtheCWFisusedtocalculatealternativelimitsandfourexamplecalculationsappliedtospecificelectroplating/metalfinishingsituations. Threeoftheexamplesdifferbecauseoftheindividualcompliancedeadlinesforthedifferentcategoricalpretreatmentstandards. Thefourthexamplerepresentsanexampleshowingconversionfromaproduction(mass)basedstandardtoaconcentrationbasedstandard. Itisimportanttorememberthatwhentwoormoreregulatedwastestreamsaremixedpriortotreatment,beforeusingtheCWFitisnecessarytodeterminewhichpretreatmentregulationappliestoeachregulatedwastestreambeforetheyaremixed.

5.6 REMOVALCREDITSAremovalcreditallowsaPOTWtoprovidecategoricalindustrialusersof

itssystemwithacredit(intheformofadjustedcategoricalpretreatmentstandards)forremovalofpollutantsbythePOTW. IndustrialusersreceivingsuchacreditareallowedtodischargetothePOTWgreaterquantitiesofregulatedpollutantsthanotherwisepermittedbyapplicablecategoricalstandards.WhetherornottoseekauthoritytograntremovalcreditsiscompletelyatthediscretionofthePOTW. Section403.7oftheGeneralPretreatmentRegulationsestablishestheconditionsunderwhichaPOTWwouldobtainapprovaltograntremovalcreditsandspecifiesthemeansbywhichtheseremovalcreditsaretobedetermined.

In1977,Congressamendedsection307(b)oftheCleanWaterActtoprovideforremovalcredits. EPAoriginallyimplementedthatprovisionandestablishedtheconditionsunderwhichPOTWscouldobtainauthorizationto

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TABLE5.2COMBINEDWASTESTREAMFORMULAS

AlternativeConcentrationLimitFormula:/ NI

Ct i=l

N X\i=i

C -alternativeconcentrationlimitforthepollutantC -CategoricalPretreatmentStandardconcentrationlimitforthepollutant

inregulatedstreamiF -averagedailyflow(atleast30dayaverage)ofregulatedstreami

-averagedailyflow(atleast30dayaverage)ofdilutewastestream(s)F -averagedailyflow(atleast30dayaverage)throughthecombined

treatmentfacility(includingregulated,unregulatedanddilutewastestreams)

N -totalnumberofregulatedstreamsAlternate Mass Limit Formula

M -alternativemasslimitforthepollutantM -CategoricalPretreatmentStandardmasslimitforthepollutantin

regulatedstreamiF -averagedailyflow(atleast30dayaverage)ofregulatedstreamiF -averagedailyflow(atleast30dayaverage)ofdilutewastestream(s)F -averagedailyflow(atleast30dayaverage)throughthecombined

treatmentfacility(includingregulated,unregulatedanddilutewastestreams)

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TABLE5.3COMBINEDWASTESTREAMFORMULAEXAMPLECALCULATION

Thefollowingexamplesprovidethecalculationsfordeterminingalternatdischargelimitsusingthecombinedwastestreamformula. Theexamplesassumecombinationsofvariousindustrieswiththefollowingwastestreams:Industrial DailyMax.Category

(Subcategory)Electroplating

WastestreamType

Regulated

Flow(mgd)0.4

ZnLimit(mg/1)

4.2Compliance

DateJune30,1984

(CommonMetals)MetalFinishing Regulated

.1(Electroplating) 0.4 2.61 February15,1986(CoatingandPainting)1 0.1 2.61PorcelainEnameling Regulated 0.075 1.33' November25,1985(Steel-coatingonly)CopperForming Regulated 0.4Mass/Produc-August15,1986

4tionBased

SanitaryWaste Dilution 0.05 N/A N/AThesearenotsubcategories; theyaremetalfinishingprocesses.2 2Alternateproductionbasedlimit=164mg/m plated.

3 2AlternateMass/Productionbasedlimits=53.3mg/m forpreparationand0.85

/2mg/m forcoating.4Mass/Productionbasedlimits=0.943mg/off-kgofcopperheattreatedforsolutionheattreatment.

Thecalculatedalternatedischargelimits(Zn )inthefollowingexamplescwfarebasedonphasedcompliancedatesforElectroplating,PorcelainEnameling,

andMetalFinishing.

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TABLE5.4(Continued)

COMBINEDWASTESTREAMFORMULAEXAMPLECALCULATIONEXAMPLEB

AlternativedischargelimitforIntegratedelectroplater/porcelain enamelerfromNovember25, 1985untilFebruary15, 1986(compliancedateformetalfinishing)

4.2mg/1(0.4mgd)+1.33mg/1(0.075mgd)"cwf (0.4mgd+0.075mgd)

(0.4 mgd +0.1 mgd+0.075mgd+0.05mgd-0.05 mgd)0.625mgd

Zn =3.45mg/1cwfNote: AlternatedischargelimitisbasedonElectroplatingandPorcelain

Enamelingcategoricalstandardsandproportionedbytheflowoftheregulatedelectroplatingandporcelainenamelingwastestreams. Duetodilutionfromsanitarywaste,thealternatedischargelimitisreduced.

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TABLE5.4(Continued)

COMBINEDWASTESTREAMFORMULAEXAMPLECALCULATION" ' EXAMPLEC

Alternativedischargelimitforintegratedelectroplater/porcelain enamelerafterFebruary15, 1986(compliancedateformetalfinishing).

2.61mg/l(0.5mgd)+1.33mg/l(0.075mgd)'"cwf (0.5mgd+0.075mgd)

(0.5 mgd+0.075mgd+0.05mgd~0.05 mgd)0.625mgd

Zn =2.25mg/l

Note: Electroplating(commonmetals)isnowcoveredbyMetalFinishing,andissubjecttoaZnlimitof2.61mg/l. Thus,thealternatedischargelimitisbasedonMetalFinishingandPorcelainEnamelingcategoricalstandardsandproportionedbytheflowofthethreeregulatedwaste-streams. Duetodilutionfromsanitarywaste,thealternatedischargelimitisreducedto2.25mg/l.

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oO"

TABLE5.4(Continued)COMBINEDWASTESTREAMFORMULAEXAMPLECALCULATION

EXAMPLEDCopperFormingandseveralothercategoricalstandardsareexpressedasproduction-basedlimits. Theexamplebelowconvertsproduction-basedlimits

toequivalentconcentration-basedlimits. Theseequivalentconcentration-basedlimitscanthenbeusedasthestandardforCopperForming.CopperForming(SolutionHeatTreatment) = 0.943mg/off-kgofcopperheatMaximumDallyLimitforZincAverageDailyProductionDuringLast12monthsAverageDallyWaterUsagein

treated=30,000off-kgofcopperheat

treatedperday=400,000gpdSolutionHeatingTreatingDuringLast12months

Step1: ConvertProduction-basedLimittoEquivalentConcentrationLimitConcentrationEquivalent (Production-BasedLlmlt)(Avg.DailyProductionRate)(Avg.DailyFlowfromRegulatedProcess)(ConversionFactor)

Zn =0-943 mg/off-kg (30,000 off-kg/day) ,(equivalent) 400,000gpd(3.785liters/gallon) '

Step2: Oncetheconcentration-based

equivalentis

determined,thenthe

alternatelimitcanbecalculatedasinExampleA.Z

ncwf

(0.019mg/1X0.4mgd)+(2.61mg/1x0.1mgd)+(1.33 mg/lx0.075mgd)

(0.4mgd+0.1mgd+0.075mgd)(0.4 mgd+0.1 mgd+0.075 mgd+0.05 mgd-0.05 mgd)0.625mgd

=0.59mg/1Note: Off-kgshallmeanthemassofcopperorecopperalloyremovedfromaforming

orancillaryoperationattheendofaprocesscyclefortransfertoadifferentmachineorprocess.

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CopperForming MetalFinishing Porcelain Sanitary(SolutionHeat (Coating&Painting) Enameling(Steel) WasteTreatment)

4mgd Q= 0. 1tngd Q=0.075mgd Q=0.05mgdZn=0.019mg/1 Zn= 2.61 Zn=1.33 Zn=N/A


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TABLE5.4