attachment 1. section 4 central valley salt nitrate ... · 4‐4 section 4 central valley salt and...

ATTACHMENT 1. SECTION 4 CENTRAL VALLEY SALT & NITRATE MANAGEMENT STRATEGY

Final SNMP for Central Valley Water Board Consideration: December 2016

Section 4

Central Valley Salt and Nitrate Management

Strategy

ElevatednitrateconcentrationsandsaltaccumulationintheCentralValleyposesignificantwaterqualitymanagementchallenges,inparticularinthegroundwaterunderlyingtheCentralValleyfloor.Theseconditionshavebeenevidentsincethe1970sandcontinuetoworsen(Johnsonetal.2012).Toreversethistrend,theCentralValleySNMPrecommendsasaltandnitratemanagementstrategythatincludesregulatoryrequirementsfortheCentralValleyRegion.BasedonthefindingsinSection3andthosedescribedbelow,thissectiondescribesanapproachtheCentralValleyWaterBoardcouldusetomanagesaltandnitrateintheCentralValleytomeetthisSNMP’smanagementgoals,wherereasonableandfeasible.

4.1 Salt & Nitrate Management Plan Framework ThefoundationforimplementationoftheCentralValleySNMPistheCentralValleyBasinPlanswhichestablishtheBoard’sexistingregulatoryauthoritytomanagesaltandnitrateintheregion.However,theexistingregulatoryframeworkintheseBasinPlanscurrentlylimitstheCentralValleyWaterBoard’sabilitytoconsiderinnovativesaltornitratemanagementstrategies,includingstrategiesconsistentwiththeintentandpurposeoftheRecycledWaterPolicyandgoalsofCV‐SALTS. Toaddresstheseregulatorylimitations,CV‐SALTSdevelopedrecommendationsformodificationsorclarificationstotheBasinPlanstofacilitateimplementationofinnovativesaltandnitratemanagementstrategiestoimprovewaterquality.Section4.2.2belowsummarizestheserecommendations.AttachmentAincorporatespolicy,strategy,andguidancedocumentsthatprovidetheregulatoryandtechnicalbasisforeachoftheserecommendations.TheCentralValleyWaterBoardmayproposeamendmentstotheBasinPlanstoincorporatetheserecommendationsintotheBasinPlans.Combined,theSNMPandtherecommendedpolicieswillestablisharevisedregulatoryframeworkthatwillprovidetheflexibilitynecessarytomakesaltandnitratemanagementdecisionsattheappropriatetemporal,geographicand/ormanagementzonescales.1

TheremainderofthissectiondescribestheoverallSNMPframeworkincludingthemanagementgoalsandprioritiesforthisSNMPandanoverviewofthegeneralapproachproposedtomanagesaltandnitratethroughouttheCentralValley.ThisSNMPframeworkisbasedonthefindingsoftechnicalstudiesthathavecharacterizedtheextentofsaltandnitrateconcernsintheCentralValleyandthetechnicalfeasibilitytomanagesaltandnitrateinamannerthatmeetstheSNMP’smanagementgoals.Ultimately,implementationofthisSNMPwillbeaniterativeandadaptiveprocessthatwillinvolveperiodicreviewandreassessmentsothatwhathasbeenlearnedby

1CV‐SALTSStrategyandFramework.http://www.cvsalinity.org/index.php/docs/committee‐document/executive‐committee‐docs/1411‐cv‐salts‐program‐work‐plan‐v‐8‐approved‐3912pdf/file.htmll

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Section 4 Central Valley Salt and Nitrate Management Strategy doingcanbeincorporatedintofuturerevisedSNMPs.WhereanysuchchangestotheSNMPrequireadditionalBasinPlanamendments,thesewillbeaddressedinatimelymanner.

4.1.1 Management Goals and Priorities InordertoachievedesiredoutcomesforthemanagementofsaltandnitratewithintheCentralValley,thisSNMPmustnotonlyaddresstherequirementsoftheRecycledWaterPolicy,butalsoaddresslegacyandongoingsaltandnitrateaccumulationissuesinamannerthatleadstoenvironmentalandeconomicsustainability.Todoso,implementationoftheCentralValleySNMPisbuiltonthefollowingthreemanagementgoals:

Goal 1: Ensure a Safe Drinking Water Supply

ThemostimportantmanagementgoalfortheCentralValleyRegionistoensurethatasafe,reliabledrinkingwatersupplyisavailabletoallresidentsoftheregion.ThisgoaladdressesthefindingsofthestatelegislatureapprovedAssemblyBill685,whichamendedtheCaliforniaWaterCodetodeclarethat,“…everyhumanbeinghastherighttosafe,clean,affordableandaccessiblewateradequateforhumanconsumption,cookingandsanitarypurposes.”2AccesstosafedrinkingwaterisespeciallycriticalinpartsoftheCentralValleywhereseveralindependentstudieshavereportedthatnitrateconcentrationsexceedtheestablishedmaximumcontaminantlevel(MCL)atnumerouswelllocationsthroughouttheCentralValley(seee.g.,Harteretal.2012;StateWaterBoard2013).Moreover,theStateWaterBoardreportedthat90publicwatersupplysystemsreportedviolationsoftheMCLfornitratein2012(seeTable4.13,StateWaterBoard2015).Theneedtoensureasafe,reliabledrinkingwatersupplyisthehighestpriorityforthemanagementofnitrateunderthisSNMPandshallbeimplementedasquicklyaspossibleinallareasintheCentralValleyRegion.

Goal 2: Achieve Balanced Salt and Nitrate Loadings

Goal2seekstoestablishabalanceofthemassofsaltandnitrateingroundwaterunderlyingeachpermittedormanagedarea,wherereasonableandfeasible.Withregardstosalt,balanceisdefinedasachievingastatewhereinputsofsalt(saltfluxin)intoamanagedareaareequaltooutputs(saltfluxout)fromthesamearea.Similarly,nitratebalancemeansabalanceofnitratefluxinandnitratefluxoutofthepermittedmanagedarea.Thenitratemassbalancewillneedtoaccountfornitratetakenupbycropsandlossesofnitratefromthenitrogencycleinsoil,includingdenitrificationintherootzonebysoilmicrobialactivityandvolatilizationtotheatmosphere.

Goal 3: Implement Managed Aquifer Restoration Program

Thisgoalseeks,wherereasonableandfeasible,torestoresaltandnitratelevelswithingroundwaterbasinsandsubbasinsorlocallymanagedareastoconcentrationsthatcomplywiththeapplicablewaterqualityobjectivesestablishedforeachconstituent.AsdemonstratedinthetechnicalworkusedtosupportthisSNMP(seeSection4.2.5),thechallengeassociatedwithsimplyachievingapplicablesaltandnitrateobjectivesinalreadyimpactedwatersissignificant.Accordingly,SNMPimplementationnotonlyfocusesonrestoringthebeneficialusewhere

2AssemblyBillNo.685added§106.3totheCaliforniaWaterCode.SignedbyGov.BrownonSeptember25,2012.

Commented [A1]: We agree and appreciate this important goal of the SNMP. However, important aspects of a safe, reliable drinking water supply include water that is aesthetically pleasing and at a reasonable cost. We are concerned that the proposed revisions to the secondary MCLs in Table 64449‐A will degrade source water quality and result in either reduced aesthetics of the treated water supply or increased water treatment and residual management costs. The implications of the SMCL guidance need to be included in the evaluation of this goal.

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Section 4 Central Valley Salt and Nitrate Management Strategy reasonableandfeasible,butalsoseekstominimizeorpreventfurtherdegradationofgroundwatersthatarecurrentlymeetingwaterqualityobjectivestoavoidfutureimpairment.

4.1.2 SNMP Overview ThisSNMPestablishestheminimumordefaultrequirementsforthemanagementofsaltandnitrateintheCentralValleyRegion.TheserequirementsaredescribedinSections4.3.2(nitrate)and4.3.3(salt)below,andwillbeimplementedthroughWDRs(individualorunderaGeneralOrder),ConditionalWaivers,orNationalPollutantDischargeEliminationSystem(NPDES)permits,asapplicable.SNMPimplementationwillbephasedacrosstheCentralValleyRegiontoallowresourcestobeallocatedtothemostsignificantwaterqualityprioritiesfirst.

Forgroundwater,thisSNMPsetsdefaultrequirementsforcomplianceapplicabletoalldischarges,basedonexistingambientwaterqualityconditionsandestimatedavailableassimilativecapacity(seeSection3.3),butallowsdischargerstodevelopdataindependentlyfortheareaundertheinfluenceoftheirdischarge(seeSection4.3.4).DevelopmentofalternativedatamaybeappropriatewhereadischargerorgroupofdischargersfindsthatthedefaultrequirementsofthisSNMParenotapplicabletothelocalareainfluencedbytheirdischargeanddataneedtobetailoredtothelocalareatobemorerepresentativeofexistingconditionswherethedischarge(s)occurandhaveinfluence.

Section4.3.2belowdescribesthenitratemanagementrequirementsunderthisSNMP.WhereagroupofdischargersdesiretoworkcollaborativelywithinadelineatedareatocomplywiththisSNMP'snitratemanagementrequirements,thesedischargersareencouragedtoestablishamanagementzoneinaccordancewiththeGroundwaterManagementZonePolicy(SeeSection4.2.2.1andAttachmentA‐1).Whereamanagementzoneisestablished,multipleWDRsorConditionalWaiversmayexistandbeaffectedbythenitratemanagementrequirementsestablishedforthemanagementzone.EachindividualdischargerwithinthemanagementzonestillmustcomplywiththerelevantWDRorConditionalWaiverthatauthorizestheirrespectivedischarge,buttheirrespectivepermitwillincludetherelevantnitratemanagementrequirementsestablishedforthemanagementzone.ForanindividualdischargerorathirdpartygroupsubjecttoaGeneralOrderthatchoosestonotparticipateinamanagementzone,orwhereamanagementzonedoesnotexist,amoretraditionalpermittingapproach(withsomemodifications)willberequiredtomeetthisSNMP’snitratemanagementrequirements.

Section4.3.3belowdescribesthesaltmanagementrequirementsunderthisSNMP.DischargerswillbestronglyencouragedtoparticipateinthisSNMP’sphasedSalinityManagementStrategy(seeAttachmentA‐3),unlessthedischarger(s)optoutandtheirdischarge(s)meetspecificoptoutrequirements.ImplementationofSalinityManagementStrategywillprovidethebasisfortheestablishmentoffuturesaltmanagementrequirementstobeimplementedthroughWDRs/ConditionalWaiversandNPDESpermits.

4.2 SNMP Development Process DevelopmentofthisSNMPhasbeenamulti‐yearprocessinvolvingfrequentstakeholdermeetings,developmentofrecommendedmodificationstotheBasinPlans,andcompletionoftechnicalstudiestoprovidethefoundationfortheSNMP’srecommendations(seeAttachmentD‐

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Section 4 Central Valley Salt and Nitrate Management Strategy 2).Belowisasummaryofthekeyactivities,documents,andstudiesthatprovidethebasisforthisSNMP.

4.2.1 CV‐SALTS ThisSNMPistheproductoftheeffortsofCV‐SALTS,abroadcoalitionofrepresentativesfromagriculture,cities,industry,stateandfederalregulatoryagencies,andthepublic(includingEnvironmentalJusticeadvocatesonbehalfofdisadvantagedcommunitiesandpopulations).Initiatedin2006,CV‐SALTSdevelopedthisenvironmentallyandeconomicallysustainableplanforthemanagementofsaltandnitrateconsistentwiththeState’sRecycledWaterPolicyandaddressinglong‐termsaltandnitrateconcernsintheCentralValleyRegion.CV‐SALTSincludessupportfromtheCentralValleySalinityCoalition(CVSC),anon‐profitorganizationandformedinJuly2008toorganize,facilitateandfundeffortsneededfortheefficientmanagementofsalinityandnitratesintheCentralValley.

ThedevelopmentofthisSNMPoccurredoveranumberofyearsprimarilythroughtheoversightoftheCV‐SALTSExecutiveCommitteeandtechnicalsupportfromaTAC.TheExecutiveCommitteeismadeupof30members:6committeechairs,6representingnon‐governmentalorganizations,federalandstateagenciesand18membersoftheCVSC.TheExecutiveCommitteeprovidesoversightofallothercommitteesinCV‐SALTSandapprovesallfinaldecisionsandactions,includingthecontentofthisSNMP.Formanyyears,thecommitteemettwicemonthly:(a)face‐to‐facepublicpolicymeetingsinSacramento,Californiawherethesaltandnitratepolicyandmanagement‐relatedelementsofthisSNMPweredevelopedcollaboratively3;and(b)publicadministrativemeetingteleconferencestodiscussprocess‐relateditemsincludingmanagementofcontracts,progressofongoingsupportingtechnicalwork,andcommitteeprocedures.AllExecutiveCommitteemeetingshavebeenheldincompliancewiththeBagley‐KeeneOpenMeetingAct;meetingagendas,notesandsupportingmaterialsareavailableatwww.cvsalinity.org.

TheCV‐SALTSTACisanall‐volunteercommitteecomprisedofstakeholderswithvaryinginterestsandexpertiseinthetechnicalissuesassociatedwithsaltandnitratemanagementintheCentralValley.TheTACmeetsperiodicallyviateleconferenceorface‐to‐facemeetingsintheSacramentoareatoprovideoversightandinputonspecificCV‐SALTStechnicalissues.AllTACmeetingsareheldincompliancewiththeBagley‐KeeneOpenMeetingAct;meetingagendas,notesandsupportingmaterialsareavailableatwww.cvsalinity.org.

4.2.2 Recommended Clarifications, Policies and New Regulatory Tools DevelopmentofthisSNMPincludedanevaluationofexistingpoliciesandrequirementsintheregion’sBasinPlansandledtothedevelopmentofrecommendedclarifications,policiesandnewregulatorytools(orstrategies)tofacilitateSNMPimplementation.TheserecommendationsaredesignedtofacilitateimplementationofthisSNMPandeffortstoachievethesaltandnitratemanagementgoals.Forthemostpart,theserecommendationsarenotself‐implementingandwillrequireadoptionofBasinPlanamendments.ThesectionsbelowprovideasummaryofCV‐SALTS

3Notably,whilethepoliciesweredevelopedwithsignificantdiscussionandcollaborationbyallinvolved,thereisnotunanimousconsensuswithrespecttosupportforallofthepoliciesbyallCV‐SALTSExecutiveCommitteeparticipants.AttachmentD‐3providesadditionalinformation.

Commented [A2]: Please see specific mark‐up comments below.

Commented [A3]: The inclusion of the SMCLs in Table 64449‐A does not affect implementation of salt or nitrate policies.

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Section 4 Central Valley Salt and Nitrate Management Strategy recommendations.4Theinformationbelowissupportedbytheciteddetailedpolicy,strategy,orguidancedocumentsprovidedinAttachmentA.

4.2.2.1 Groundwater Management Areas

Default Groundwater Management Areas

TheintentofRecycledWaterPolicySection6.b.(1)(a)isforeverygroundwaterbasin/subbasinintheCentralValleytohaveaconsistentsaltandnitratemanagementplan.DWRBulletin118defines,delineates,anddescribesthegroundwaterbasinsandsubbasinsintheCentralValleyRegion(DWR2003).5Thesebasins/subbasinswillserveasdefaultmanagementareasunlessagroupofdischargerselectstoestablishamanagementzone,whichmayestablishanalternativeareaforthemanagementofnitrateingroundwater(seediscussionbelowandSection4.3.2).HighresolutionmappingwasdevelopedfortheCentralValleyRegion,whichmaybeusedtosupportthedevelopmentofappropriatemanagementarea.

TheBasinPlansfortheCentralValleyincluderequirementsfortheprotectionofgroundwaterqualitythroughtheestablishmentofwaterqualityobjectivesandprogramsofimplementationtoachievethewaterqualityobjectives.Currently,theTLBBasinPlanidentifiesgroundwaterbasinsandsubbasinsinTableII‐2that,forthemostpart,matchthoseshowninBulletin118.6However,whenDWRBulletin118waslastupdated(DWR2003),DWRdeletedseveralofthesubbasins.TLBBasinPlanTableII‐2hasnotbeensimilarlyrevisedtoreflectDWR'schanges.7TheSRSJBBasinPlandoesnotcurrentlyidentifyorenumeratespecificgroundwaterbasinsorsubbasins,asidentifiedbyDWR’sBulletin118.

DWRperiodicallyrevisestheboundariesofgroundwaterbasins/subbasins.Therefore,eveniftheBasinPlansareupdatedtoincorporatetheexisting,publisheddelineation,thisinformationcouldbecomeoutdatedrequiringadditionalBasinPlanamendments.Giventhatchangestogroundwaterbasin/subbasindelineationswilloccurinthefuture,itmaynotbeappropriatetodirectlyincorporateDWR’sgroundwaterbasin/subbasindesignationsintotheBasinPlans.Instead,aspartoftheplannedupdatetotheBasinPlanstoincorporatetheSNMP,theCentralValleyWaterBoardwillconsiderthebestapproachforreferencingDWR‐delineatedgroundwaterbasins/subbasinsintheBasinPlanstoallowforfuturechanges.

Groundwater Management Zone Policy (Attachment A‐1)

TheSNMPrecommendsestablishmentofaprogrammaticapproachtonitratemanagementintheCentralValleyRegion.Aspartoftheprogrammaticapproach,theSNMPrecommendsthattheBasinPlansbeamendedtoallowandencouragemanagementofnitratethroughthe

4ThisSNMPwasdevelopedthroughaprocessthatprovidedseveralopportunitiesforcommentstobesubmittedbyExecutivePolicyCommitteemembers.Attemptsweremadetoaddressallcommentsreceived,butdisagreementsremainwithrespecttosomekeyaspectsoftheSNMPrecommendedpolicies.AttachmentD‐3summarizeskeyalternativeproposalsubmitted.

5TheTLBBasinPlanfurtherdividesoneofthesegroundwaterbasinsintothreehydrographicunits,seeTLBBasinPlanFigureIII‐1.6TLBBasinPlan,pagesII‐5&II‐6.7Thefollowing“SatelliteBasins”listedintheTLBBasinPlanwereremovedasgroundwatersubbasinsintheDWR2013update:SquawValley,CedarGroveArea,ThreeRiversArea,SpringvilleArea,TempletonMountainArea,MonacheMeadowsArea,SecatorCanyonValley,RockhouseMeadowValley,InnsValley(LinnsValleyinTLBBasinPlan),BearValley

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Section 4 Central Valley Salt and Nitrate Management Strategy establishmentofmanagementzones.Ingeneral,amanagementzonewouldconsistofmultipledischargersworkingcollectivelytoensurefirstsafedrinkingwater,thentomanagenitratestocreateabalancewithinthedefinedmanagementarea(wherereasonableandfeasible),andultimatelytodevelopandimplementalong‐termplanforrestorationofgroundwater(wherereasonableandfeasible)tomeetapplicablewaterqualityobjectives.

AlthoughtheBasinPlansdonotcurrentlypreventthemanagementofnitratesthroughthecreationofmanagementzones,theSNMPrecommendstheinclusionofaGroundwaterManagementZonePolicywithintheBasinPlanssothatwhatconstitutesapropermanagementzoneisclearlydefinedandtoensurethatcriteriaforapprovalofamanagementzonebytheCentralValleyWaterBoardareproperlyestablishedinregulation.ThejustificationforauthorizingtheestablishmentofmanagementzonesisexpressedinvariousstatewideandCentralValleyWaterBoardpolicies(seediscussioninAttachmentA‐1).Withrespecttosalinity,managementzonesmaybeappropriateinthefuturebutarenotpracticalatthistime.Rather,salinityisbeingaddressedindependentlyfromnitratesintheSalinityManagementStrategy(seeSection4.3.3belowandAttachmentA‐3).

4.2.2.2 Permitting and Management Strategies Nitrate Permitting Strategy (Attachment A‐2)

TheSNMPprovidesthebasisforthemanagementofnitrateintheCentralValley.FordischargersregulatedbytheCentralValleyWaterBoard,thesemanagementeffortsmustultimatelybeimplementedindischargepermitsissuedtodischargers.WDRsandConditionalWaiversmustensurethatthereceivingwaterwillmeetthewaterqualityobjective,andthatdischargesdonotcauseorcontributetoanexceedanceofthewaterqualityobjective.InsomeareasoftheCentralValley,andforsometypesofdischargers,thetraditionalpermittingapproachfornitratesmaynotbefeasible,reasonableorpracticable.Accordingly,CV‐SALTSdevelopedanSNMPNitratePermittingStrategythatsetsforthrecommendationswithrespecttopermittingnitratedischargesinWDRsandConditionalWaiversunderthetraditionalpermittingapproachaswellasprovidingforalternativepermittingapproaches.AttachmentA‐2providesadetaileddiscussionoftheNitratePermittingStrategythatissummarizedinSection4.3.2below.

Salinity Management Strategy (Attachment A‐3)

TheSNMPanditsassociatedtechnicaldocumentsproposelong‐termsolutionsforaddressingsalinity.Forexample,theStrategicSaltAccumulationLandandTransportationStudy(SSALTS)identifiedandevaluatedpotentialsaltmanagementstrategies(CDMSmith2013,2014,and2016b).Thestudy’sfindingsshowedthatcurrentsalinitymanagementactivitiesmayonlyaddressabout15%oftheannualsaltload;long‐termsolutions,includingdevelopmentofregionalde‐salters,aregulatedbrineline,orotherprojectsthatwouldallowcontainmentorremovalofsalt,areneededtoaddresstheother85%.Theselong‐termmanagementstrategieswillrequiresignificantstateandfederalfundingtoimplement.Inthemeantime,theCentralValleyWaterBoardmustimplementtheBasinPlansthroughtheadoptionofWDRs/ConditionalWaiversthatconsiderthebeneficialusestobeprotectedandthewaterqualityobjectivesassociatedwiththosebeneficialuses.

Becausethesolutionsforaddressingsalinityarelong‐terminnature,theCentralValleyWaterBoardneedsbeabletoconsiderinnovativesaltmanagementstrategiesforboththeshortterm

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Section 4 Central Valley Salt and Nitrate Management Strategy andthelongtermthatmovetheregiontowardsaltbalanceandrestorationofimpactedareas,wherereasonableandfeasible.ThisincludesneedingadditionalregulatoryflexibilitywithrespecttotheissuanceofWDRs/ConditionalWaiverswithsalinity‐relatedrequirements.SomeofthisflexibilitycanbeobtainedthroughtheimplementationofrecommendedCV‐SALTSpoliciesandguidanceasdescribedbelowinSection4.2.2.3.Inaddition,tosupplementthesepoliciesorguidance,CV‐SALTShasestablishedaSalinityManagementStrategythatrecommendsaprocessformovingforwardwithaphasedlong‐termsalinitymanagementprogram.Thisprogramincludes(1)arecommendationforremovalofexistingsalinity‐relatedlimitationsintheTLBBasinPlanImplementationChapter;and(2)adoptionofaproposedInterimSalinityPermittingApproachforsalinitydischargesduringimplementationofthefirstphaseoftheSalinityManagementStrategy.AttachmentA‐3providesadetaileddiscussionoftheSalinityManagementStrategythatissummarizedinSection4.3.3below.

4.2.2.3 Policies and Guidance

Exceptions Policy (Attachment A‐4)

AttachmentA‐4providesthebasisforrecommendationtoamendtheBasinPlanstorevisetheexistingCentralValleySalinityExceptionsProgram.Thisprogramwaspreviouslyestablishedforthefollowingreasons:Whereadischargeisnotbetterthantheapplicablewaterqualityobjectiveandnoassimilativecapacityisavailable,theBasinPlansrequiredtheCentralValleyWaterBoardtoprohibitthedischarge,adoptatimescheduleintheorderthatallowsthedischargertocomeintocompliancewithneededWDRprovisions,orrevisetheapplicablewaterqualitystandard.Becausethesetraditionalremedieswerenotalwaysappropriateforsalt,theBoardadoptedanExceptionsPolicyintheBasinPlansthatincludesaSalinityExceptionProgramtobeineffectduringtheCV‐SALTSprocess.

TheexistingExceptionsPolicyprohibitstheCentralValleyWaterBoardfromauthorizingnewexceptionsorreauthorizingpreviouslyapprovedexceptionsrelatedtosalinityafterJune30,2019.Inaddition,theSalinityExceptionProgramappliesonlytoTDS/EC,chloride,sulfateandsodiumanddoesnotidentifyguidelinesforanexceptiontobeauthorizedfornitratewaterqualityobjectives.ThisSNMPrecommendsrevisingtheexistingExceptionsPolicybyamendingtheBasinPlansinthefollowingmanner:

AddnitratetothelistofchemicalconstituentsforwhichtheCentralValleyWaterBoardmayauthorizeanexception;

Expand/reviseconditionsorauthorizationofanexceptiontoreflectthegoalsoftheSNMP;

Removetheexistingsunsetprovisionthatprohibitsthegrantingofsalinityexceptions

beyondJune30,2019;and Deletethecurrentprovisionlimitingthetermofanexceptiontonomorethan10yearsand

addanewprovisionstatingthatwhenauthorizinganexception,theCentralValleyWaterBoardshalladoptatermfortheexception.Termsforexceptionsshallgenerallynotexceed10years,however,theCentralValleyWaterBoardshallhavethediscretiontoadoptanexceptionforlongerthan10yearsiftheapplicant(s)candemonstratethatitisnecessarytofurtherthemanagementgoalsoftheSNMP.RetaintheCentralValleyWaterBoard’s

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Section 4 Central Valley Salt and Nitrate Management Strategy

authoritytoreauthorize(renew)anexceptionforoneormoreadditionalterms,thelengthofwhichshallbedeterminedbytheCentralValleyWaterBoard.

Salinity Management to Provide Reasonable Protection of AGR Beneficial Uses in Groundwater (AGR Policy) (Attachment A‐5)

SignificantchallengesexistinestablishingpermitlimitstoprotecttheAGRbeneficialuse.AttachmentA‐5providesadetaileddiscussionoftheissues;followingisasummary.TheAGRbeneficialusewasdesignedtoprotectbothcropirrigationandlivestockwateringandhasbeendesignatedinthemajorityofsurfacewatersandgroundwaterthroughouttheCentralValley.AlthoughthewaterqualityobjectivestoprotecttheAGRbeneficialusearenarrative,currentlynoguidanceexistsonhowtointerpretthenarrativeobjectiveinamannerthataccountsforlocalandregionaldifferences.Asadefault,aconservativeapproachensuresprotectionofthemostsensitivecropinalllocationsatalltimes(e.g.,EC<700µS/cm)hasbeenutilized,eventhoughindividualcropandlivestocksensitivitytosalinityvarieswidelyandpotentialimpactscanbemitigatedthroughmanagementactivities.8

TheapplicationofthisconservativeapproachtoprotectingtheAGRbeneficialusecreatesanumberofissuesforresolution:

Impactsontheabilityofdischargerstomanage/maximizereuseofdrainagewateron

progressivelymoresalttolerantcrops. Manysubbasinsandlocalizedareashaveelevatedbackgroundsaltconcentrationsthatare

higherthan700µS/cm. Duetoconsumptiveuse,veryhighqualityirrigationwaterwouldbeneededtoensure700

µS/cmindrainagebelowtherootzoneundercommonpractices. Giventheabovefindings,clarificationisneededregardinghowsalinitywillbemanagedwithineachgroundwaterbasin/subbasintoprovidetheappropriatelevelofprotectionoftheAGRbeneficialuseandestablishprocedurestominimizedegradationandwhereneededreducesaltloadingtoachievebalanceandensurelong‐termprotectionoftheAGRuse.Accordingly,theAGRPolicyascurrentlyformulatedrecommendstheBasinPlansbeamendedtoassignAGRClassestogroundwaterbasins/subbasinsbasedoncurrentambientsaltconcentrationsintheproductionzoneofeachbasin/subbasin.Specifically,

AGRClass1:TDS<600mg/L(EC<1,000µS/cm).Groundwaterqualityintheproductionzonethatmaybeusedasanagriculturalwatersupplyisgenerallysuitableforirrigatingallcropsandallstockwatering.

AGRClass2:600mg/L<TDS<2,000mg/L(1,000µS/cm<EC<3,000µS/cm).Groundwaterqualityintheproductionzonethatmaybeusedasanagriculturalwatersupplyisgenerallyacceptableforstockwateringandforirrigatingmostsalt‐tolerantcrops;

8InStateWaterBoardOrderWQO2004‐0010,theStateWaterBoardrecognizedthatuseofthemostconservativevaluefortheprotectionofthemostsaltsensitivecropmaynotbeappropriateandthattheRegionalBoardmustconsidersite‐specificconditionsandallowsomerelaxationasdeterminedappropriate.

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itisnotgenerallysuitableforirrigatingmanysalt‐sensitivecrops,exceptasatemporary,short‐termalternativewhenhigherqualitywatersuppliesarenotreadilyavailable.

AGRClass3:2,000mg/L<TDS<5,000mg/L(3,000µS/cm<EC<7,500µS/cm).

Groundwaterqualityintheproductionzonethatmaybeusedasanagriculturalwatersupplyisgenerallyacceptableforstockwateringbutisnotgenerallysuitableforirrigatingallbutthemostsalt‐tolerantcrops,exceptasatemporary,short‐termalternativewhenhigherwaterqualitywatersuppliesarenotreadilyavailable.

AGRClass4:TDS>5,000mg/L(EC>7,500µS/cm).GroundwaterqualityintheproductionzonethatisnotsuitableforeitherstockwateringorcropirrigationAGRusesunlessblendedwithlowersalinitywater.AreaswithinthisclassificationshouldbeconsideredforAGRde‐designation.

TheAGRclassesasdescribedabovearenotproposedforincorporationintotheBasinPlansatthistime.Instead,theassignmentofthesepotentialclassesandtheirassociatedTDS/ECranges,basedonambientTDS/ECconcentrationintheproductionzoneofgroundwaterbasins/subbasins,willbeevaluatedovertimeaspartoftheimplementationoftheSalinityManagementsectionofthisSNMP.AftercompletionofthePhaseI–PrioritizationandOptimizationStudy(seeSection4.3.3),theseAGRclassesandtheirrangesorotherapproacheswillbere‐evaluatedforpotentialinclusionintheBasinPlansthroughafutureamendmentprocess.

Salinity Variance Policy (Attachment A‐6)

OnJune6,2014,theCentralValleyWaterBoardadoptedamendmentstotheBasinPlansthatincludedaVarianceProgramforSalinity(SalinityVarianceProgram)9.OnMarch17,2015,theStateWaterBoardadoptedResolutionNo.2015‐0010approvingBasinPlanamendmentstoincludetheSalinityVarianceProgram.BecausetheSalinityVarianceProgramappliestosurfacewaters,andisconsideredawaterqualitystandardsactionundertheCleanWaterAct,theSalinityVarianceProgramwassubjecttoapprovalbytheUnitedStatesEnvironmentalProtectionAgency(USEPA).USEPAapprovedtheSalinityVarianceProgramonJuly8,2016.Withitsapproval,U.S.EPAspecificallylimitedapplicationoftheSalinityVarianceProgramtoeffluentlimitationsbeingadoptedtoprotecttheAGRbeneficialuse.Further,theSalinityVarianceProgramappliesonlytomunicipalpublicallyownedtreatmentworks(POTWs)thathaveasituationsimilartoorcomparabletothecasestudycitiesincludedintheCentralValleyWaterBoard’ssupportingdocuments.

WhenitadoptedtheSalinityVarianceProgram,theCentralValleyWaterBoardrecognizedthatmanagementofsalinityinsurfaceandgroundwatersisamajorchallengefordischargers.TheCentralValleyWaterBoardfurtherdeterminedthatduringthedevelopmentandinitialimplementationoftheSNMP,inpreparationbyCV‐SALTS,itwasappropriatetoallowmunicipalanddomesticwastewaterdischargersthatqualifiedtoapplyforavariancefromsalinitywater

9CentralValleyWaterBoardResolutionNo.R5‐2014‐0074.

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Section 4 Central Valley Salt and Nitrate Management Strategy qualitystandardsiftheyhave,orwillhave,waterqualitybasedeffluentlimitationsforsalinitythattheyareunabletomeet.10

TheSalinityVarianceProgramappliestosalinitywaterqualitystandardsthataredefinedtoincludewaterqualitystandardsforonlythefollowingconstituents:electricalconductivity,totaldissolvedsolids,chloride,sulfateandsodium.ThecurrentSalinityVarianceProgramprohibitstheCentralValleyWaterBoardfromapprovinganysalinityvarianceafterJune30,2019.ThesunsetdatewasincludedbecausetheCentralValleyWaterBoardintendedthatanyextension,orpermanent,long‐termSalinityVarianceProgramshouldbedevelopedthroughtheCV‐SALTSprocessandthatstakeholdersneededtomakeappropriaterecommendationsforsuchapolicyintheSNMP.InaccordancewiththeCentralValleyWaterBoard’sdirectionindevelopingthecurrentSalinityVarianceProgram,thisSNMPrecommendsthattheSalinityVarianceProgrambeextendedforanadditional15years.SeeAttachmentA‐6foradditionalinformation.

Offsets Policy (Attachment A‐7)

AnoffsetisanalternativemeansofachievingcompliancewithaWDR,eitheraloneorincombinationwithotheractions,foragivenpollutantorpollutants.Anoffsetallowsforthemanagementofothersourcesandloads(notdirectlyassociatedwiththeregulateddischarge)sothatthecombinedneteffectonreceivingwaterqualityfromthedischargeandtheoffsetisfunctionally‐equivalentto(andpotentiallybetter)thanthatwhichwouldhaveoccurredbyrequiringthedischargertocomplywithitsWDRatthepoint‐of‐discharge.Inthisregard,anoffsetprojectmustbelocatedwithinthesamegroundwaterbasin/subbasinormanagementzoneastheregulateddischarge.

TheSNMPincludesanOffsetsPolicy(seeAttachmentA‐7),whichrecommendsthattheBasinPlansbeamendedtoprovideauthorityfortheCentralValleyWaterBoardtoallowtheuseofoffsetprojectstocomplywithWDRs,butonlyforgroundwater.InadditiontoanoffsetprojectbeingusedtosupportcompliancewithaWDR,offsetsmaybeproposedtosupportarequestforeitheranallocationofavailableassimilativecapacityoranexception(seeNitratePermittingStrategy[AttachmentA‐2]andExceptionsPolicy[AttachmentA‐4],respectively).Ultimately,thedecisiontopursueanoffsetisvoluntary.Offsetsmustbe(1)proposedbydischarger(individualorgroupofdischargers)asanAlternativeComplianceProject(ACP,seeAttachmentA‐10andsummarybelow);(2)approvedbytheCentralValleyWaterBoard;and(3)enforceablethroughaWDRorotherordersissuedbytheBoard.

Asnotedabove,thisSNMPrecommendsthattheOffsetsPolicybeapplicableonlytogroundwateratthistime.However,duringimplementationofthePhaseI–PrioritizationandOptimizationStudy(seeSNMPAttachmentA‐3andSection4.3.3,SaltManagement,below),anOffsetPolicyforsurfacewatermaybeconsideredforpotentialinclusionintheBasinPlansthroughafutureBasinPlanamendmentprocess.

10AmendmentstotheWaterQualityControlPlanfortheSacramentoRiverandSanJoaquinRiverBasinsandtheWaterQualityControlPlanfortheTulareLakeBasintoaddPoliciesforVariancesfromSurfaceWaterQualityStandardsforPointSourceDischargers,VarianceProgramforSalinity,andExceptionfromImplementationofWaterQualityObjectivesforSalinity,FinalStaffReport,June2014(FinalStaffReport),atp.45.

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Section 4 Central Valley Salt and Nitrate Management Strategy Finally,tosupportimplementationofthispolicy,itmaybeappropriatetoestablishamitigationfunddesignedtodevelopandimplementwaterqualityimprovementprojectswithinthesamereceivingwaterbasin,subbasinormanagementzonewherethedischargeoccurs.Thismaybeparticularlyusefulforpoolingtheresourcesofmanyrelativelysmalldischargersintoacriticalmassoffundingtosupportwaterqualityprojectsthatwouldnormallybebeyondthemeansofindividualdischargerstofund.EstablishmentofamitigationfundwilllikelyrequireCalifornialegislation.Accordingly,whilethisSNMPsupportstheuseofamitigationfundtosupportimplementationofthispolicy,noneareproposedtobeestablishedatthistime.

Drought and Water Conservation Policy (Attachment A‐8)

Theeffectsofdroughtandtheimplementationofencouragedormandatedwaterconservationpracticescansignificantlyimpacteffluentqualityindischargestosurfacewaterorgroundwater.AttachmentA‐8providesadetaileddiscussionoftheseissues.ThetextbelowprovidesanoverviewandsummaryofrecommendationstosupportimplementationofthisSNMP.

Historically,WDRs/ConditionalWaiversrarelyhaveincludedanyspecialprovisionorconsiderationforvariationsineffluentquality,directlyorindirectlyrelatedtorecurrentdroughtconditionsthatarebeyondthecontrolofthedischargerorforongoing,expandingandsometimesmandatedconservationpractices.However,extendedperiodsofbelownormalprecipitation(i.e.,“droughts”)aswellasextensiveconservationpracticescancreatecomplianceissuesforsomedischargersbecauseofincreasedTDS/ECandothersalinity‐relatedconstituentsininfluentandeffluent.Thisproblemiscausedbythefollowingconditionsassociatedwithperiodsofdrought:

Whenlesshighquality(lowTDS/EC)surfacewaterisavailable,wateragenciesmayincreaserelianceonlowerquality(higherTDS/EC)groundorlowerqualitysurfacewatertoaugmentsupplies.MosttreatmentsystemsarenotdesignedtoremoveTDS/EC;thushighersalinityinthewatersupplycanresultinhighersalinityineffluent.

Mandatoryconservationmeasuresduringprolongeddroughtmaysignificantlyalterthebehaviorofwaterusers.Thecumulativeeffectisreducedwateruse,whichpreviouslyhelpeddiluteaverageTDS/ECconcentrationinrawsewageandtreatedwastewater.

Drought‐relatedchangesinwaterqualitymaytemporarilyaggravatethemorepermanentlong‐termtrendtowardsincreasedTDS/ECininfluentcausedbyadoptionofhighefficiency,low‐flowfixturesandappliances,andgreateruseofin‐homewatersofteners.

Evenwherewastewaterfacilitiesareabletohandlealong‐termtrendofrisingTDS/ECintheinfluent,drought‐relatedconditionsmaytemporarilyeliminatethesmallbutcriticalbufferneededtoassureconsistentcompliancewithsalinity‐basedpermitdischargerequirements.

Droughtconditionscreatesimilarconcernsforagriculturaloperatorsandindustrialusers.Reducedavailabilityofhighquality(lowTDS/EC)surfacewaterforcesincreasedrelianceonlowerquality(highTDS/EC)sources(e.g.,groundwaterand/orreuseofirrigationreturnflows),resultingintemporarilyhigherTDS/ECconcentrationsrechargingtogroundwaterbelowtherootzone.Theinabilitytoassureconsistentpermitcomplianceforsalinitydiscouragestheuseofrecycledwaterforlandscapeorcropirrigationandmay

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createdisincentivestogreaterimplementationofmoreefficient(drip‐style)irrigationsystems.

Oncewaterconservationpracticesareimplemented,theyarelikelytocontinue,especially

iftheynecessitatedcapitalinvestment(i.e.redirectionforlandscapeirrigation,lowflushtoilets,dripirrigation,etc.).

Finally,permiteffluentrequirementsforTDS/ECaretypicallyevaluatedusingrelativelyshort‐termaveragingperiods(e.g.,daily,weekly,monthlyaveragesormeans).Sincedroughtstypicallypersistforseveralyears,evenpermitlimitsexpressedasanannualaveragemaybeimpracticaltomeet.

Giventheaboveconcerns,theSNMPproposesamendmentstotheBasinPlanthatspecificallyaddresssalinity‐relatedconcernsassociatedwiththeimpactsofdroughtorincreasedimplementationofwaterconservationpractices.Specifically,

Fordischargestogroundwater,calculatecompliancewiththeapplicablenarrativeornumericsalinityobjectivesusingalong‐term(10+year)flow‐weightedaveragewhilealsotakingintoconsiderationtheexpectedrechargeandpotentialdilutionfromnaturalprecipitationandstreambedpercolationtothesamebasinorsubbasin.

AuthorizetheuseofoffsetprojectsconsistentwiththisSNMP’sOffsetsPolicy(seeAttachmentA‐7),particularlyincreasedstormwatercaptureandrecharge,todemonstratecompliancewithWDRsgoverningsalinitydischarges.AllowoffsetcreditstobecreatedandbankedbyconstructingandoperatingsuchprojectsorbydischargingwellbelowtheWDRthresholdinnon‐droughtyears.Recognizethatthecreditsneededtoachievecomplianceduringperiodsofdroughtnormallymustbegeneratedattimesofabovenormalprecipitation(especiallyElNiñowinters)and,assuch,mustremainvalidoverasufficientlylongplanninghorizon,i.e.,atleast20yearsinordertobeuseful.

ConsideramendingtheBasinPlanstoestablishatemporaryvariance/exceptionfromsalinity‐relatedstandardsduringcertaindroughtconditions.Thevariance/exceptionwouldbeautomaticallyactivatedwhenoneofthefollowingtriggersoccurs:(a)adroughtemergencyisdeclaredbyanauthorizedfederalorstateauthority;11(b)duringanextendeddryperiodinReach83oftheLowerSanJoaquinRiver(MercedtoVernalis)asdefinedbytheSRSJRBasinPlans;12or(c)declarationofalocalemergencyconsistentwiththeCaliforniaEmergencyServicesAct.13Atsuchtimes,moreappropriateinterimWDRsoreffluentlimits,suchastheshorttermMCLof2,200µmhos/cmEC,wouldapply.

ConsideramendingtheBasinPlanstoestablishatemporaryvariance/exceptionfromsalinity‐relatedstandardswheretheTDS/ECconcentrationinthepermitteddischargeis

11CaliforniaGovernmentCodeSectionTitle2,Division1,Chapter7,CaliforniaEmergencyServicesAct;alsoseehttp://www.water.ca.gov/waterconditions/declaration.cfm12SeeproposedBasinPlanamendment:EstablishmentofSalinityWaterQualityObjectivesintheLowerSanJoaquinRiver,fromtheMouthoftheMercedRivertoVernalis.http://www.waterboards.ca.gov/centralvalley/water_issues/salinity/upstream_salt_boron/index.shtml13CaliforniaGovernmentCodeSectionTitle2,Division1,Chapter7,CaliforniaEmergencyServicesAct.

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better(lower)thantheTDS/ECconcentrationinthereceivingwaterandwillimprovereceivingwaterquality(evenwhenthereceivingwaterqualityishigherthantheSMCL)bypromotingmaximumuse/reuseofavailablewatersupplies.Potentialimpactstodownstream/downgradientwaterqualitymustalsobeevaluatedaspartofthisdemonstration.

Inlieuofauthorizingatemporaryvariance/exception,considerpre‐authorizinganautomaticallocationofassimilativecapacity(whereitexists,orcanbeprovidedbythedischarger,e.g.,viaanoffsetproject)toaccommodatehigherTDSconcentrationsinthedischarge/rechargeduringdroughtconditions.

Guidance to Implement Secondary Maximum Contaminant Levels (Attachment A‐9)

TheSNMPincludesrecommendationsfortheincorporationofguidanceintotheBasinPlanstosupportandclarifyimplementationofSecondaryMaximumContaminantLevels(SMCL)inpermitsfordischargetosurfacewaterandgroundwater(seeAttachmentA‐9).SMCLsaresecondarydrinkingwaterstandards,definedbytheCaliforniaHealthandSafetyCodeas:

“…standardsthatspecifymaximumcontaminantlevelsthat,inthejudgmentofthedepartment,arenecessarytoprotectthepublicwelfare.Secondarydrinkingwaterstandardsmayapplytoanycontaminantindrinkingwaterthatmayadverselyaffecttheodororappearanceofthewaterandmaycauseasubstantialnumberofpersonsservedbythepublicwatersystemtodiscontinueitsuse,orthatmayotherwiseadverselyaffectthepublicwelfare.Regulationsestablishingsecondarydrinkingwaterstandardsmayvaryaccordingtogeographicandothercircumstancesandmayapplytoanycontaminantindrinkingwaterthatadverselyaffectsthetaste,odor,orappearanceofthewaterwhenthestandardsarenecessarytoensureasupplyofpure,wholesome,andpotablewater.”14

FollowingaretheareaswhereclarificationorguidanceisrecommendedtosupporttheimplementationofSMCLsindischargepermits: SMCLsestablishedby22CCR(thedrinkingwaterregulations)areincorporatedby

referenceintheChemicalConstituentsectionsintheWaterQualityObjectivesChapteroftheBasinPlans.Theonlyportionsof22CCRrelatedtoSMCLsandincorporatedintotheBasinPlansareTables64449‐Aand64449‐B(Tables4‐1and4‐2,respectively).Table64449‐Bincludes“Recommended”,“Upper”,and“ShortTerm”concentrationsforTDSorSpecificConductanceorEC,chlorideandsulfate.WhiletheSMCLswereincludedintheBasinPlansforthepurposeofprotectingthedrinkingwateruse,neitherthetextprovidingcontextforthetablesnorguidanceforutilizingtheapplicable“Recommended”,“Upper”,or“ShortTerm”concentrationswasincludedwhenthe22CCRtableswereadoptedaswaterqualityobjectives.ThelackofguidanceonthetierednumericvaluesinTable64449‐BhasledtoinconsistentapplicationinWDRs.

14CaliforniaHealthandSafetyCode,Division104EnvironmentalHealth,Part12DrinkingWater,Chapter4CaliforniaSafeDrinkingWaterAct,Article1,Section116275(d)


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Table 4‐1. Table 64449‐A: Secondary Maximum Contaminant Levels; “Consumer Acceptance Contaminant Levels” (22 CCR §64449)

Constituents Maximum Contaminant Levels/Units

Aluminum 0.2 mg/L

Color 15 Units

Copper 1.0 mg/L

Foaming Agents (MBAS) 0.5 mg/L

Iron 0.3 mg/L

Manganese 0.05 mg/L

Methyl‐tert‐butyl ether (MTBE) 0.005 mg/L

Odor – Threshold 3 Units

Silver 0.1 mg/L

Thiobencarb 0.001 mg/L

Turbidity 5 Units

Zinc 5.0 mg/L

Table 4‐2. Table 64449‐B: Secondary Maximum Contaminant Levels; “Consumer Acceptance Contaminant Level Ranges” (22 CCR §64449)

Constituents, Units Recommended Upper Short Term

Total Dissolved Solids (TDS), mg/L, or

Specific Conductance, µS/cm15

500 1,000 1,500

900 1,600 2,200

Chloride, mg/L 250 500 600

Sulfate, mg/L 250 500 600

InCalifornia,thesecondarydrinkingwaterstandardsareenforceableandcommunitywatersystemsarerequiredtoassesscompliancewithSMCLsbymonitoringtheirsurfacewaterorgroundwatersourcesormonitoringtheirdistributionsystementrypointsfollowingsourcetreatment.16Groundwaterundergoessomenaturalfiltrationasthatwatermovesthroughthevadosezone.USEPA'sdrinkingwaterregulationsrequirenearlyallsurfacewatersourcestobefiltered.17Therefore,inmostcases,thewaterusedtodemonstratecompliancewiththeSMCLshasbeenfilteredbeforetherepresentativesamplesarecollected.Thereisnoneedforthecommunitywatersystemstoapplyanyadditionalfiltrationtothesamplebeforeitisanalyzed.

Fordischargestogroundwater,wastewatersamplescollectedatthepoint‐of‐dischargehavenothadanopportunitytoundergotheprocessofnaturalfiltrationthatoccursassuchdischargespercolatethroughthevadosezonebeforereachingtheaquifer.Filteringsuch

15 For the purposes of this policy, Specific Conductance is expressed as Electrical Conductivity. 16 22 CCR §64449(b) 17 US EPA. National Primary Drinking Water Regulations: Long Term 2 Enhanced Surface Water Treatment Rule. 71 FR 654. January 5, 2006. Exceptions are sometimes granted for community water systems that rely that rely protected watersheds (ex. Hetch‐Hetchy reservoir).

Commented [A4]: Many surface waters are low in secondary MCL contaminants and source treatment is not required, therefore water utilities monitor the source water for compliance. Drinking water filtration applied is not equivalent to the dissolved analysis filtration at 0.45 um.

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samples,priortoacidifyingandanalyzingthesample,isintendedtomimicthenaturalfiltrationprocessthatisexpectedtooccurbeforethesedischargestogroundwatermightbepumpedfromadowngradientwellbyacommunitywatersystem.Fordischargestosurfacewater,wastewatersamplesshouldbesubjectedtothesamefiltrationrequirementsthatcommunitywatersystemsarerequiredtomeetbeforesuchsamplesareacidifiedandanalyzedtodeterminecompliancewiththeSMCLsfortracemetals.Requiringdischargerstouseanunfilteredsampleimproperlyassumesthatthewastewaterwillbeusedasadrinkingwatersupplywithnoadditionalnaturalorman‐madetreatmentbetweenthepoint‐of‐dischargeandtheentrypointtothemunicipalwaterdistributionsystem.Asbothapracticalandlegalmatter,thatisneverthecase.

TheBasinPlansdonotcurrentlyprovideguidanceontheassessmentperiodthatshouldbeusedtodeterminecompliancewithSMCLs.Per22CCR§64449,compliancewiththeSMCLsinTable64449‐AandTable64449‐Bfordrinkingwatersystemsvariesdependingonthesource,withgroundwatersourcesbasedonasingletriennialsampleandsurfacewatersourcesbasedonasingleannualsample.ItisrecommendedthattheBasinPlansbeamendedtoincorporatetextthatdefinestheassessmentperiodfordeterminingcompliancewithSMCLs.Specifically,languageshouldbeaddedtotheimplementationsectionoftheBasinPlanstostatethatanevaluationofcompliancewithSMCLsinTables64449‐Aand64449‐Bshallbeataminimumbasedonanannualaverageofcollectedsamplesfromallanalyticalresultscollectedfromwherecomplianceisdetermined.Thisapproachissimilarto22CCR§64449(c)(1)asitappliestoTable64449‐A.22CCR§64449doesnotprovideacompliancedeterminationapproachforTable64449‐Bconstituents;regardless,thesamecomplianceassessmentapproachisrecommendedfortheconstituentsinbothTable64449‐Aand64449‐B.

Guidance for Developing Alternative Compliance Projects for Nitrate Discharges (Attachment A‐10)

Whenanindividual(orthirdpartygroupsubjecttoaGeneralOrder)orgroupofdischargersisunabletodemonstratethattheirdischargeisnotindividuallyorcollectivelycausingorcontributingtonitratedegradationabovethetriggersidentifiedintheCentralValleySNMP(seeSection4.3.2andAttachmentA‐2),theyhaveanopportunitytorequesteitherallocationofavailableassimilativecapacityoranexception.Inmostcases,therequestforthegrantingofassimilativecapacity18oranexceptioninthesecircumstancesrequiressubmittalofaproposedACP.Thisrequestmaybemadeasanindividualdischarger(whichincludesathirdpartygroupsubjecttoaGeneralOrder)ordischargersworkingcollaborativelyaspartofagroundwatermanagementzone.WhiletheCentralValleyWaterBoardhasthediscretiontodenysucharequest,anyproposedACP(s)submittedforconsiderationmustcontainspecificcomponents.AttachmentA‐10providesguidanceoftheminimumcomponentsrequiredforsubmittalofanACPforapproval.Examplesofthekeyminimumcomponentsinclude:

18Conditionswithrespecttograntingofassimilativecapacitywillvary,dependingonhowthereceivingwaterisdefinedforthedischarge(s)inquestion.Insomecases,thereceivingwaterwillbeconsideredtobeshallowgroundwater,whileinothers,itmaybetheupperzoneorproductionzoneasdefinedatSection3.

Commented [A5]: The SRSWPP disagrees with the plan to use 0.45 micron filtered water results for compliance with various SMCLs. See attached supporting information, previously provided to CV‐Salts. DDW confirmed in comments provided on 8/1/16 that filtered metals results are not used for drinking water compliance monitoring. We request that the issue of fate and transport of metals be further reviewed to ensure that the policy provides appropriate long‐term protection of source water quality.

Commented [A6]: Please include information on mechanisms available to dischargers for relief, including how dilution credits and mixing zones are used.


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ConsistencywiththemanagementgoalsoftheCentralValleySNMP,includingaddressingshort‐termandlong‐termdrinkingwaterneedsaffectedbynitrates,planforachievingbalancednitrateloadingswithintheproposedboundariesoftheproject,wherefeasibleandreasonable,andaplanforestablishingamanagedaquiferrestorationprogramtorestorenitratelevelstoconcentrationsatorbelowthewaterqualityobjectivestoextentreasonableandfeasible.

Assurethatdrinkingwaterthatmeetsdrinkingwaterstandardsisavailabletodrinkingwateruserswithinthezoneofinfluenceofadischargewheretherearesignificantnitrateconcernsingroundwater.ThiscomponentmaybemetthroughthedevelopmentandimplementationofanEarlyActionPlan(EAP)(e.g.,seeSection4.3.2.1belowortheNitratePermittingStrategy[AttachmentA‐2]).

Outreachthatwilloccurtoinsurethatstakeholdersoraffectedcommunitieswithinthezoneofinfluenceofadischarge,includingcommunitieswithdrinkingwaterqualityconcerns,areinformedof,andgivenopportunitytoparticipatein,thedevelopmentofanyACPproposalaswellasongoingactivitiesdesignedtoresolvetheirdrinkingwaterconcerns.

Identificationofshort(≤20years)andlong‐term(>20years)projectsand/orplanningactivitiesthatwillbeimplementedaspartoftheACPtomakeprogresstowardsattainingeachofthewaterquality‐relatedmanagementgoalsestablishedbytheCentralValleySNMPwithinthezoneofinfluence.Formanagementzones,projects/planningactivitiesmaybeprioritizedtobetterallocateresources.Overtimeaswaterqualityimprovesinprioritizedareas,updatestotheACPmayshiftthepriorities.

Shortandlong‐termschedulesforimplementationofnitratemanagementactivitieswithinterimmilestonesandperformancemeasurestoassessprogress,andidentificationoftriggersfortheimplementationofalternativeproceduresormeasurestobeimplementediftheinterimmilestonesarenotmet.

SurveillanceandmonitoringprogramthatisadequatetoassurethattheACPwhenimplementedisachievingtheexpectedprogresstowardsattainmentofwaterquality‐relatedmanagementgoals.

Identificationoftheresponsibilitiesofeachregulateddischarger,orgroupsofregulateddischargersifparticipatinginamanagementzone,tomanagenitrate.

Factors to Support a Maximum Benefit Finding (Attachment A‐11)

TheStateAntidegradationPolicy(No.68‐16)setsforththespecificconditionsthatmustbemetanddemonstrationsthatmustbemadebeforetheCentralValleyWaterBoardcanallowadischarge(ordischarges)tolowerwaterqualityinanexistinghighqualitywater:

(1) “Whenevertheexistingqualityofwaterisbetterthanthequalityestablishedinpoliciesasofthedateonwhichsuchpoliciesbecomeeffective,suchexistinghighqualitywillbemaintaineduntilithasbeendemonstratedtotheStatethatanychangewillbeconsistentwithmaximumbenefittothepeopleoftheState,willnotunreasonablyaffectpresent

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andanticipatedbeneficialuseofsuchwaterandwillnotresultinwaterqualitylessthanthatprescribedinthepolicies.

(2) Anyactivitywhichproducesormayproduceawasteorincreasedvolumeorconcentration

ofwasteandwhichdischargesorproposestodischargetoexistinghighqualitywaterswillberequiredtomeetwastedischargerequirementswhichwillresultinthebestpracticabletreatmentorcontrolofthedischargenecessarytoassurethat(a)apollutionornuisancewillnotoccurand(b)thehighestwaterqualityconsistentwithmaximumbenefittothepeopleoftheStatewillbemaintained”(emphasisadded).19

TosupportimplementationofthisSNMP,itsproposedmanagementstrategiesandpolicies,AttachmentA‐11providesguidanceformakingafindingthataproposedprojectmeetsthetestthatitsapprovalandimplementationwouldbe“consistentwiththemaximumbenefittothepeopleofthestate”test,asstatedintheStateAntidegradationPolicy.

4.2.3 Related Basin Plan Amendments InparallelwiththedevelopmentofthisSNMPandrecommendationsforBasinPlanamendmentstosupportitsimplementation,CV‐SALTShasbeendevelopingotherBasinPlanamendmentsthatsupportsalinity‐relatedmanagementrequirementsonawaterbodyorwatershed‐specificbasis.TheserelatedBasinPlanamendmentsandpotentiallinkagestothisSNMParesummarizedbelow.

4.2.3.1 MUN Beneficial Use Project – Agriculturally Dominated Water Bodies Evaluation PertheState’sSourcesofDrinkingWaterPolicy(StateWaterBoardResolutionNo.88‐63)theBasinPlansdesignateMUNasabeneficialuseonallwaterbodiesunlesstheyarespecificallylistedaswaterbodiesthatarenotdesignatedwithMUN.TheBasinPlansstatethatwatersdesignatedforMUNmustnotexceedMaximumContaminantLevels(MCLs,primaryorsecondary)forchemicalconstituents,pesticides,andradionuclides,andvariousnarrativestandardsthatapplytoMUN(aswellasotherbeneficialuses).WhileResolution88‐63doescontainexceptionsfortheMUNdesignationsuchaswaterbodiesconstructedormodifiedfortheprimarypurposetoconveyorholdagriculturaldrainage,toutilizetheexceptiontheBasinPlansrequireaformalBasinPlanamendment.

DuringNPDESpermitadoptionstherehavebeenchallengestotheneedtoprotecttheMUNbeneficialusedesignationinagriculturaldrainsduetotheexceptionsidentifiedinStatePolicy88‐63.Concurrently,CV‐SALTSidentifiedtheneedtoevaluatetheprotectionofMUNbeneficialusesinagriculturallydominatedwaterbodies.CV‐SALTS,incoordinationwithCentralValleyWaterBoardstaff,conducteditsMUNevaluationofthesetypesofwaterbodiesintwophases:

AgriculturalDrainsReceivingTreatedWastewater‐CV‐SALTSidentifiedreceivingwatersoffourPOTWs(CitiesofWillows,Colusa,BiggsandLiveOak)aspotentialcasestudiesforevaluatingtheappropriatenessoftheMUNdesignation.ThecostforwastewaterfacilitiestocomplywithprotectingtheMUNbeneficialusehadbeenestimatedat$3‐$7million

19StateWaterBoard.StatementofPolicywithRespecttoMaintainingHighQualityofWatersinCalifornia.ResolutionNo.68‐16(October28,1968).

Commented [A7]: Please see mark‐up comments below.

Commented [A8]: Since there are two separate Basin Plan Amendments that could significantly impact the protection of the MUN beneficial use (SMCL Policy and MUN De/Re‐Designation), should there be a cumulative impact analysis of these two programs? Removing significant amounts of designated waterbodies and also reducing protections of SMCLs could cumulatively degrade downstream water quality and impact the MUN use.

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(e.g.,CityofWillows)andthesesamePOTWschallengedtheMUNdesignationduringrenewaloftheirNPDESpermits.FollowingthecompletionofrequiredanalysesandconsistentwithStatePolicy88‐63toproposeremovalofMUNfromthereceivingwater,CentralValleyWaterBoardstaffpreparedthedocumentationtosupportaBasinPlanamendmenttoremoveMUNfrom12waterbodiesagriculturaldrainagesdownstreamofthesefourPOTWs.Allofthesewatersbodiesmetexceptioncriterion2bintheSourcesofDrinkingWaterResolution88‐63.ThisBasinPlanamendmentwasapprovedbytheCentralValleyWaterBoardandStateWaterBoardonApril15andAugust18,2015,respectively)20andapprovedbytheEnvironmentalProtectionAgencyonApril21,2016.Inpart,theamendmentdevelopedastandardizedmethodforevaluatingandcategorizingagriculturallydominatedwaterbodiesintoconstructed,modifiedornatural.

Region‐wideMUNEvaluationProcessandAdoptionofaLimitedMUNBeneficialUse–TheCentralValleyWaterBoardiscurrentlyworkingonasecondBasinPlanamendmenttoestablishaCentralValleyregion‐wideprocessforevaluatingtheMUNbeneficialuseinagriculturallydominatedsurfacewaterbodiesbasedontheprocessutilizedinPhase1andadoptaLimitedMUN(LMUN)use.Ifadopted,theBasinPlanswouldareproposedtobeamendedto:

EstablishanewwaterbodycategorizationframeworkthattheBoardcouldutilizetodeterminetheappropriateapplicationof,andlevelofprotectionfor,theMUNbeneficialuseindifferenttypesofagriculturallydominatedsurfacewaterbodiesacrosstheCentralValley.TheproposedBasinPlanamendmentdistinguishesamongagriculturally‐dominatedwaterbodiesthathavebeenconstructedormodifiedfortheprimarypurposetoconveyorholdagriculturaldrainage,waterbodiesthathavebeenconstructedormodifiedtoconveyagriculturalsupplywater,naturalwaterbodiesdominatedbyagriculturaloperations,andwaterbodiesencompassedinapermanentorseasonalclosedrecirculatingbasin.Theamendmentproposestoutilize,whereappropriate,SourcesofDrinkingWaterPolicy88‐63Exception2btode‐designatetheMUNbeneficialuse.

EstablishanewLMUNbeneficialuse,proposedtobedefinedas:“Usesofwaterformunicipalanddomesticsupplyinagriculturallydominatedsurfacewaterbodieswheretheuseislimitedbywaterbodycharacteristicssuchasintermittentflow,managementtomaintainintendedagriculturaluseand/orconstituentconcentrationsinthewaterbody.”TointerpretthenarrativeobjectiveandtoevaluatecompliancewiththeproposedobjectiveforLMUN,existingmonitoringprogramsmayusenumerictriggersforchemicalconstituents,pesticides,andradionuclidesconcentrationintheirprocessofissuingpermitsorwastedischargerequirements.Exceedancesofthetriggerswouldnotbeviolationsoftheproposednarrativeobjectivenorarethetriggerstobeusedfornumericeffluentlimits.Triggerswillbeusedtoevaluateimpactstodownstreambeneficialusesandensureappropriatemanagementandbestpracticaltreatmentactionsaretakentoprotectthosedownstreamuses.

DischargerscanfinditextremelydifficulttomaintainagriculturaloperationsandincreasewaterrecyclingeffortswhilealsocomplyingwithMCLs(especiallyforsalinity‐relatedconstituents)in

Commented [A9]: We recommend this sentence be deleted or revised substantially. The BPA did not include a method for evaluating and categorizing ag dominated waterbodies in it. All of these de‐designations were predicated on application of SDWP Exception 2b to ag drainages and all supporting materials were related to that exception. No method for other ag dominated waterbody evaluations was presented or approved in the Amendment.

Commented [A10]: We recommend this deletion as it could be misinterpreted that the POTW BPA (Phase 1) created and utilized a method to be used in Phase 2, which is not the case. All the de‐designations in the POTW BPA (Phase 1) met the SDWP Exception 2b and did not require application of a new evaluation method. The new method to evaluate ag dominated water bodies will need to be approved by the Regional Board as part of this regionwide BPA.

Commented [A11]: Suggested edits from the SRSWPP, as the LMUN definition and water quality objective have not yet been approved by the Regional Board. We continue to have comments and concerns on these items.

Commented [A12]: It remains to be considered if there is sufficient long‐term monitoring planned to ensure long‐term protection of the LMUN water bodies for future water use as well as protection of downstream MUN use. It appears to be premature to include “existing” in the SNMP ahead of completion of the BPA public process for the MUN project.

Commented [A13]: There are other narrative WQO that apply to MUN that will not have triggers and they should also be considered when evaluating impacts to downstream MUN.

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20CentralValleyWaterBoardResolutionNo.R5‐2015‐0022;StateWaterBoardResolutionNo.2015‐0055

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Section 4 Central Valley Salt and Nitrate Management Strategy agriculturaldrainsthatwerenotconstructedfortheprimarypurposetosupplydrinkingwater.Consequently,establishmentofaregion‐wideprocesstoevaluatetheapplicabilityoftheMUNbeneficialuseonagriculturaldrainsprovidesanimportanttooltosupportimplementationofthisSNMP.TheBasinPlanamendmentisexpectedtobeproposedforadoptionin2017.21

4.2.3.2 Evaluation of MUN and AGR Beneficial Uses in a Portion of Historical Tulare Lakebed Groundwater TheCentralValleyWaterBoard,inconjunctionwithCV‐SALTS,isproposingtoamendtheTLBBasinPlantode‐designateMUNandAGRbeneficialusedesignationsfromaportionofthegroundwaterinthehistoricTulareLakebed.22TheProjectStudyAreaislocatedinthesouthernpartoftheCentralValleyofCaliforniaintheTulareLakeBasin.TheTulareLakeBasinessentiallyfunctionsasaclosedbasinexceptduringextremefloodyears,whensomeKingsRiverwatermovesnorththroughFresnoSloughintotheSanJoaquinRiver.BecausetheTulareLakeBasinisaclosedbasin,saltshavebeennaturallydepositedandaccumulatedsinceitsformationandbeforeanyinfluencefromhumans.Thediversionofwaterintothebasinfromotherwatershedstosupport3millionacresofagriculture,(Sholes2006)includingthreeofthefivemostagriculturallyproductivecountiesintheUnitedStates,23hasexacerbatedtheaccumulationofsalts.TheapplicationofMUNandAGRinthecenterofthehistoricLakeBedhasimpededeffortstoconsolidateandmanagesaltinevaporationbasins. Inadditiontothepotentialde‐designationofMUNandAGRbeneficialusesfromaportionofthegroundwaterundertheTulareLakebed,anotherimportantoutcomeofthiseffortistheestablishmentofaframeworkforevaluatingtheapplicabilityoftheMUNandAGRbeneficialusesandassociatedwaterqualityobjectives,includingimplementationprovisionsapplicableinspecificgroundwaterbasins.ThisframeworkwhichmaybeincorporatedintotheBasinPlans,canprovideanadditionaltoolfortosupportSNMPimplementation.Specifically,theframeworkmaybeappropriateundercertaincircumstancestoevaluatetheapplicabilityofMUNand/orAGRbeneficialusesingroundwatertoencouragereuseandrecycling.Establishingtoolstodeterminetheapplicabilityoftheseusesmayalsoprovideregulatedentitieswithmoreflexibilityinmanaginglimitedwatersupplies,andtheabilitytoidentifypotentialsaltmanagementareasthatwouldhelpmovesaltoutofsensitiveareas.ThisBasinPlanamendmentisexpectedtobeproposedforadoptionin2017.

4.2.3.3 Lower San Joaquin River Salinity Water Quality Objectives

TheCentralValleyWaterBoardisproposingamendmentstotheSRSJRBasinPlanthatwouldestablishsalinitywaterqualityobjectivesinReach83oftheLowerSanJoaquinRiver(LSJR),whichisdefinedastheLSJRfromthemouthoftheMercedRivertoVernalis.Ifadopted,theproposedamendmentwould:

DefinesalinitywaterqualityobjectivesthatareprotectiveofbeneficialusesintheLSJR.Specifically,theamendmentwouldestablishawaterqualityobjectivethatwouldrequire

21http://www.waterboards.ca.gov/centralvalley/water_issues/salinity/mun_beneficial_use/index.shtml22http://www.waterboards.ca.gov/centralvalley/water_issues/salinity/tulare_lakebed_mun_evaluation/index.shtml23http://agcomm.co.tulare.ca.us/default/assets/File/2012CensusCA_1.pdf

Commented [A14]: Please clarify if the issues are only for agricultural drains, or if there are issues with agricultural dominated water bodies.

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thatEC(at25degreesCelsius)notexceed1,550(µS/cm)asa30‐dayrunningaverage,exceptduringExtendedDryPeriods,24whenthewaterqualityobjectivewouldrequirethatECnotexceed2,470µS/cmasa30‐dayrunningaverageand2,200µS/cmastheaverageofthepreviousfourconsecutivequarterlysamplesataminimum.

IncorporateintotheSRSJRBasinPlananimplementationprogramtoachieveproposedsalinitywaterqualityobjectives.

Setaperformancegoalof1,350µS/cmduringcertainmonthsandwateryeartypes,based

onmodelingresultsofexpectedwaterquality. Requiretheimplementationofamonitoringandsurveillanceprogramtoevaluatethe

effectivenessoftheimplementationprogram. TheseproposedamendmentswouldsetobjectivesthatwouldbeprotectiveofthetwobeneficialusesintheLSJRthataremostsensitivetosalinityimpacts:AGRandMUN.MUNandtheirrigationsupplycomponentofAGRweredeterminedtobethemostsaltsensitiveusedaftercompletionofseparatestudiesonsalinityimpactstoaquaticlife(Buchwalter2014)andstockwatering(Kennedy/JenksConsulting2013).Inaddition,settinganECperformancegoalwillpromoteachievementofthebestpossiblewaterqualityundervariableconditions,consistentwiththeSNMPDroughtandWaterConservationPolicy(seeAttachmentA‐8).TheproposedamendmentsdonotchangeorreplacetheECwaterqualityobjectivesfortheSanJoaquinRiverattheAirportWayBridgenearVernalisestablishedforwaterenteringthesouthernDelta.25.

TodeterminesalinitylevelsprotectiveofirrigatedagricultureutilizingtheLSJRforsupply,theproposedamendmentusedtheHoffmanModelwithspecificinputsasfollows:

Selectingthemostsaltsensitivecropfromcropscomprising95%ofthecommercial

acreage(i.e.,almonds); Utilizinga15%leachingfraction;

Protectingto95%yield;and

Protectingin95%ofthedriestyears.

Inputswereadjustedtoprotect70%yieldduringextendeddryperiods.

Theproposedwaterqualityobjectivesaretheresultofastakeholder‐driveneffortledbytheLSJRCommittee,whichisasubcommitteeofCV‐SALTS.TheoutcomeofthisSRSJRBasinPlanamendmenteffortwillguidesaltmanagementintheSanJoaquinRiverwatershed,consistentwiththegoalsoftheSNMPanditsproposedSalinityManagementStrategy.Inaddition,theproposedamendmentprovidesguidanceon:interpretingnarrativeobjectivestoprotectAGR;

24Seefootnote2in:http://www.waterboards.ca.gov/centralvalley/board_decisions/tentative_orders/1608/mun_wkshp/1608_lsjr_wkshp_mtrl.pdf25WaterQualityControlPlanfortheSanFranciscoBay/Sacramento‐SanJoaquinDeltaEstuary,StateWaterResourcesControlBoard,December13,2006.

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Section 4 Central Valley Salt and Nitrate Management Strategy adjustingregulationtoaccountforextendeddryperiods;andmanagingsaltatabasin‐widescale.TheBasinPlanamendmentisexpectedtobeproposedforadoptionin2017.26

4.2.4 Regulatory Evaluations CV‐SALTSconductedseveralregulatoryandliteraturereviewstoevaluatethetechnicalbasisforprotectionofselectedbeneficialuses.Morespecifically,thesestudiesevaluatedwhatconstitutesreasonableprotectionofexistingandprobablefutureusesforprotectionofMUN,AGRandaquaticlife,asrelatedtonitrateand/orsalt.ThespecificevaluationscompletedaresummarizedinthesubsectionsbelowandthecompletefindingsareaccessiblethroughtheTechnicalProjectsIndexlocatedattheCV‐SALTSwebsite;27theyarealsoaccessibleinAttachmentB.1ofthisSNMP.

4.2.4.1 Salinity Effects on MUN‐related Uses of Water

CV‐SALTScompletedresearchtodefinewhatconstitutesreasonableprotectionofexistingandprobablefutureMUNuses.Thiseffortfocusedonanevaluationofthecurrentstateofknowledgeregardingtheeffectsofelevatedsalinityconcentrationsondrinkingwatersupply,includinghumanhealthconcerns,andotherdomesticusesofwatersuchasimpactsofsalinityonresidential,commercialandindustrialwater‐usingdevices.ThisstudyalsoreviewedwaterqualityobjectivesestablishedinotherCaliforniaregions,federalrecommendationsfortheprotectionofwaterusedasadrinkingwatersupplydevelopedbytheUSEPA,MUN‐relatedwaterqualitystandardsadoptedbyotherstates,andguidelinesestablishedbyselectedinternationalentities.Theoutcomewasasummaryofkeyfindingsalongwithsupportingdataandreferences(CDMSmith2016d).

4.2.4.2 Salinity Effects on Agricultural Irrigation Uses

ComparabletoitsevaluationoftheMUNuse,CV‐SALTSevaluatedwhatconstitutesreasonableprotectionofexistingandprobablefutureuseofwaterforagriculturalirrigation.Thisresearchincludedanevaluationofthecurrentstateofknowledgeregardingtheeffectsofelevatedsalinityconcentrationsoncropyields,wetlandplantsandvegetationcommonlyusedforlandscaping.Inaddition,thestudyreviewedwaterqualityobjectivesestablishedinotherCaliforniaregions,federalrecommendationsdevelopedbytheUSEPA,waterqualitystandardsadoptedbyotherstatestoprotectwaterusedforirrigation,andguidelinesestablishedbyselectedinternationalentities.Theoutcomewasasummaryofthekeyfindingsalongwithsupportingdataandreferences(CDMSmith2016c).

4.2.4.3 Stock Watering Protection

TheCentralValleyRegionprotectsstockwateringsuppliesthroughapplicationoftheAGRbeneficialuse.CV‐SALTSconductedresearchtoidentifywaterqualitycriteriathatmaybeusedtoestablishsalinityandnitrate‐relatedwaterqualityobjectivestoprotectstockwateringsuppliesintheCentralValley.Thisstudyconsideredthefollowinginformationsources:(a)waterqualityobjectivesestablishedinotherregionsofCaliforniaorinotherselectedstates;(b)reviewofUSEPArecommendations;(c)universityextensionpublicationsandspecialists;(d)publishedpeer‐reviewedliterature;and(e)selectedinternationalagencies.ThefinalreportprovidedCV‐SALTS

26http://www.waterboards.ca.gov/centralvalley/water_issues/salinity/upstream_salt_boron/index.shtml

27http://www.cvsalinity.org/index.php/committees/technical‐advisory/technical‐projects‐index.html

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Section 4 Central Valley Salt and Nitrate Management Strategy withrecommendationsforprotectionofstockwateringsources(Kennedy/JenksConsultants2013).

4.2.4.4 Aquatic Life Protection

CV‐SALTSimplementedastudytoidentifypotentialwaterqualitycriteriathatcouldbeusedtoestablishsalinity‐relatedwaterqualityobjectivestoprotectaquaticlifeinCentralValleysurfacewaters.Thisstudyresearchedthefollowinginformationsources:(a)recentliteraturereviewsconductedbyselectedstatestoestablishwaterqualitycriteriaforsalinity‐relatedconstituents;(b)peer‐reviewedpublishedliterature;(c)dataandmethodologiesdevelopedbyfederalagencies,includingUSEPAandtheUnitedStatesDepartmentofInterior;(d)recommendationsdevelopedbyselectedinternationalagencies;and(e)anyinformationdevelopedbyotherCaliforniaagencies.ThefinalreportprovidedtechnicalrecommendationsforCV‐SALTSconsideration(Buchwalter2014).

4.2.5 Development of the Technical Foundation CV‐SALTScommissionedanumberoftechnicalstudiesovermanyyearstodevelopbaselineinformationtosupportthisSNMP.ThespecificstudiescompletedineachofthesecategoriesaswellasspecificfindingsareaccessiblethroughtheTechnicalProjectsIndexlocatedattheCV‐SALTSwebsite;28theyarealsoaccessibleinAttachmentBofthisSNMP.Inthesubsectionsbelow,summariesareprovidedforthekeystudiesthathavebeenusedto(a)supportdevelopmentofthepolicies,strategiesandregulatorytoolsdescribedinSection4.2.2aboveandinSections4.3.2(nitratemanagement)and4.3.3(saltmanagement)below;and(b)fulfillthesaltandnitratecharacterizationrequirementsdescribedintheRecycledWaterPolicy,inparticularSection6.b(3)(d),anddiscussedinSection3.

4.2.5.1 Nitrate Management

TosupportthedevelopmentofthisSNMP,CV‐SALTScompletedstudiestoprovidethetechnicalbasisfortheestablishmentofanitratemanagementprogramtoachievetheCentralValley’sshortandlong‐termmanagementgoals.ThefindingsfromthesestudieshavebeencoupledwithexistingregulatoryprogramstomanagewaterqualityandthepolicyrecommendationsofthisSNMPtoprovideafoundationforthedevelopmentoftheNitratePermittingStrategytobeimplementedthroughWDRs/ConditionalWaivers.

ExistingnitratemonitoringandmanagementprogramsincludetheIrrigatedLandsRegulatoryProgram(ILRP),theDairyGeneralOrder,andrelatedRepresentativeMonitoringProgram,andexistingWDRs,someofwhichmayalreadyincluderequirementsforthemanagementofnitrate.TheseprogramsprovidethefoundationuponwhichthenitrateimplementationmeasuresidentifiedthroughCV‐SALTSstudiescanbuildtoachievethegoalsofnitratemanagementfortheCentralValley.Forexample,throughtheILRPtheCentralValleyWaterBoardhasadoptedregulatoryrequirementsfordischargesfromirrigatedlandsthroughissuanceofGeneralWDROrders.Underthisprogram,growersmayjointhird‐partygroups(i.e.,coalitionsofgrowers),whichmaybegeographicorcommodity‐based.WDRsissuedtogrowersthataremembersofathird‐partyalreadyincluderequirementstoimplementbestmanagementpracticeswithrespect

28http://www.cvsalinity.org/index.php/committees/technical‐advisory/technical‐projects‐index.html

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Section 4 Central Valley Salt and Nitrate Management Strategy tonitrogenapplicationsinordertomanagenitrogeninthepermittedarea.Asanotherexample,theCentralValleyWaterBoardalreadyregulatesover1300dairiesthroughaGeneralOrderthat“servesasgeneralwastedischargerequirementsfordischargesofwastefromexistingmilkcowdairiesofallsize.”TheseGeneralOrdersprovidethefoundationuponwhichimplementationoftheSNMPwilloccur.

Nitrate Implementation Measures Study (NIMS)

CV‐SALTSconductedtheNIMStoprovideinputtopolicymakersregardingimplementationmeasurestoreducecurrentambientnitrateconcentrationsingroundwatertoprotectandrestorebeneficialuses,consistentwiththisSNMP’smanagementgoals(CDMSmith2016a).Findingsfromthisstudythatreviewedliteraturesourcesanddevelopedindependentestimatesshowedthatthemanagementofnitratetoachievenitratebalanceandtorestorethebeneficialusewherenitratecurrentlyexceedsthewaterqualityobjectiverepresentsasignificantchallengethatwillrequirebothshort‐termandlong‐termimplementationmeasures. TheNIMSevaluatedrequirementstoachievenitratebalanceusingCV‐SALTSdatadevelopedaspartoftheICMproject(LarryWalkerAssociatesetal.2013).Theanalysisshowedthatthenitrateloadingtotheshallowgroundwaterzonevalley‐widerangesfrom97,500to311,000tonsannually.Between78and86percentofthetotalnitrateloadingoccursintheSouthernCentralValley.Thesefindingsillustratetheamountofnitrateloadingthatwillneedtobecontrolledtoachievenitratebalance.Moreover,thelargelegacynitrateloadinthevadosezone,whichwasnotconsideredinthesefindings,willexacerbatefurthernitratewaterqualityconcerns.

Withregardstomanagedrestoration,Kingetal.(2012)estimatedthattherangeofannualizedremediationcoststopumpandtreatthevolumeofgroundwaterthatexceeds10mg/LintheTulareLakeBasinalonetobe$12to$27.6billion.Thisestimatedidnotincludethepipelineorpumpingcostsfortransportofwaterfromremotelocationstoacentralizedtreatmentfacility.NIMSperformedthesameanalysisforthegroundwaterunderlyingtheCentralValleyfloor–SacramentoRiverValley,SanJoaquinRiverValley,andtheTulareLakeBasin.Again,withoutincludingthecostsforextractionwells,rawandtreatedwaterpipelines(andothernecessaryinfrastructure)andusingthesameunittreatmentcostsandassumptionsasKingetal.(2012),thecostfortreatinggroundwaterthatexceeds10mg/LintheCentralValleywouldrangefrom$36to$81billion.Thecostsformanagedrestorationwouldcertainlybeloweratasmallerscale,e.g.,withinadefinedmanagementzone,butwouldstillbeintherangeoftensofmillionsofdollarsforcapitalcostsandmillionsforannualoperationandmaintenancecosts(CDMSmith2016a,seeTable5‐6).

Inadditiontothefindingsofpotentialsignificantcostsassociatedwithachievingrestoration,NIMSdevelopedanestimateofthetimerequiredtoachievevariouslevelsofrestoration(nitrateconcentrationsatorbelowthe10mg/LMCL)withinaspecificstudyarea,i.e.,theAltaIrrigationDistrict(AID)inKingsCounty.Forexample,underapump,treat,andreinjectscenarioataspecifiedextractionrate,itwasestimatedthatitwouldtakemorethan70yearstoachieve10mg/Lnitrateinthegroundwater;doublingtherateofextractionwouldlowerthistimeframeto37years.Otherscenarioswereevaluated,e.g.,pump,treatandserve,butthetimetorestorationorachievingthe10mg/LMCLfornitratewasstillsignificant(CDMSmith2016a).

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Section 4 Central Valley Salt and Nitrate Management Strategy NIMSestablishedamenuofnitrateimplementationmeasuresornitrateremediationtechnologiesforconsiderationbydischargers.Thesetechnologiesfellintooneoftwocategories:(a)exsitu–groundwaterextractionandtreatmentfollowedbyreinjection,dischargeorpotablereuse;and(b)insitutreatment‐NIMSprovidesacomparisonofthetechnologiesbasedondifferentfactors(e.g.,costs,easeofpermitting,orsecondaryimpacts)andapplicabilityofthetechnologiesunderdifferentconditions(e.g.,existingnitrateconcentrations,systemsizeorcontaminantdepth)(CDMSmith2016a).ThisinformationcanbeusedtosupporteffortstomeetrequirementstoachievenitratebalanceormanagerestorationwherefeasibleintheCentralValleyRegion,consistentwiththisSNMPsnitratemanagementrequirements.

Aggressive Restoration Modeling Scenario

TheNIMSstudysummarizedaboveidentifiedanumberofpotentialnitratemanagementcontrols(e.g.,pump,treat,andserve,orpump,treat,andre‐inject)thatcouldbedeployedintheCentralValleytoimprovewaterquality.TheAIDManagementZoneArchetypeStudy,discussedbelowinSection4.2.5.3,evaluatedanumberofmanagementscenariosandthepotentialbenefitstowaterqualitywithintheAIDarea.TobetterunderstandthetypesofnitratecontrolmeasuresthatwouldbenecessarytomeetSNMPmanagementgoal#3(ImplementManagedAquiferRestorationProgram),amodelingstudy,i.e.,AggressiveRestorationModelingScenario,wascompletedthatlinkedmanagementScenario#3fromtheAIDManagementZoneArchetypeStudy(withspecifiedtargetsforirrigationefficiency,reducednitrogenloading,andartificialrechargechanges)withselectednitratemanagementcontrolsidentifiedbytheNIMSandon‐farmwinterrecharge.ThestudyevaluatedtwoselectedareaswithintheAIDboundary(DinubaandCutler/Orosi)withvaryingnitrateconditions.Wellfieldsweredesignedforeachofthestudyareasandthenmodeledtoobservethedegreetowhichnitratedecreasesinambientgroundwaterwithin10to20years(andaslongas100years)usingdifferentsimulations.Keyfindingsincluded(Luhdorff&ScalmaniniConsultingEngineersandLarryWalkerAssociates2016b):

Atargetedapproachforrestorationworksbetterinsmallergeographicsettingswhere

thereismorecontrolandknowledgeaboutthelocaltransportofwaterandnitratemass. Applyingpump,treat,andreinjectdesignstolargeregionalareasisnotpracticablebecause

therearetoomanyothercomplicationssuchasnon‐pointsources,localrural/urban/domesticpumpingstresses,andlateralinfluxesthatinterferewiththemovementandrestorationofthewaterthatisattemptedwiththepump,treat,andreinjectsystemdesign.

Withregardstouseofon‐farmrechargeasamanagementcontrol:(a)Itisadvantageousforflushingtherootzonewithcleanwater,buttheeffectsoftheincreasedrechargearenotalwaysdiscernibleinthepreciseareaoftherechargeactivityandrechargeeffectsmaybeseendowngradientandmaybeaffectedbynearbypumpingstresses;(b)itaidsintheverticalmovementofcleanwater,butcanalsoresultindisplacementofexistingpoorshallowwaterqualitycausingthiswatertomovedownwardintolowerpartsoftheaquifersystem,sometimesincludingtheproductionzone;and(c)on‐farmrechargeandanyattemptsatenhancednaturalrechargeorartificialrechargearegreatlydependentontheabilityoftheaquifermaterialsandwatertableelevationtoacceptadditionalwater.

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Pump,treat,andserveeffortsratherthanpump,treat,andreinjectareanexcellentwaytoprovidecleandrinkingwatertocommunities,butthisapproachdoesnotserveasaparticularlybeneficialtoolforrestoration.Theamountofnitratemassremovedfrommunicipalpumpingisminorcomparedtotheamountofmassenteringthesystemthroughsurfacemassloadingandlateralfluxesonaregionalscale.Mostofthepump,treat,andservewaterisconsumed;therefore,littletreatedwaterreturnstotheaquifersystem,offeringlittleornoreplenishmenttotheaquifer.

RestorationisnotlikelyfeasibleonthescaleoftheCentralValley.Itappearstobeunrealisticevenonthescaleofthearchetypestudyarea,AID,asitwouldlikelytakeontheorderofthousandsofnewwellstopump,treat,andreinjectcleanwaterbackintothesystemwhileinterceptingsurfacemassloadingsbeforetheymigratedownintotheproductionzone.Localizedeffortsinareasthatareofhighpriority(basedonproximitytocommunitiesandexistingambientconditions)maybepotentiallyidealforrestorationactivitiesthatmayincludeon‐farmrecharge,otherartificialrechargeefforts,andpump/treat/reinjectefforts.Evenso,restorationactivitiesmaytakedecadestoresultinsatisfactorydeclinesinimpairedgroundwaterquality,andeventuallytheareasmayreachequilibriumwherethenitratemassenteringthesystemequalsthemassexiting.Therefore,targetedreductionsinnitrateconcentrationsmaystillbedifficulttoachieve.

4.2.5.2 Salt Management

TosupportthedevelopmentofthisCentralValleySNMP,CV‐SALTScompletedaphasedstudytoprovidethetechnicalbasisfortheestablishmentofasaltmanagementprogramtoachievetheCentralValley’smanagementgoals.ThefindingsfromthisworkcoupledwiththepolicyrecommendationsofthisSNMPprovidedafoundationforthedevelopmentoftheSalinityManagementStrategy,aphasedsalinitymanagementprogramtobeimplementedintheCentralValley(seeAttachmentA‐3).

SSALTSdescribedexamplesofongoingeffortstomanagesaltintheCentralValley,whichmaybeusedasarchetypesforhowsaltcouldbemanagedbyotherdischargers(CDMSmith2013).Inaddition,SSALTSidentifiedtherangeofavailableCentralValleyalternativesforsaltmanagement,storageordisposalconsideringin‐valley,out‐of‐valley,orcombinationsofinandout‐of‐valleysolutions(CDMSmith2014).Evaluatedin‐valleysaltmanagement,storage,ordisposalalternativesincludedsourcecontrolBMPs,landmanagement,applicationoftreatmenttechnologies,deepwellinjection,andsupplyforhydraulicfracturing.Out‐of‐valleyalternativesfocusedontwostrategies:(a)oceandisposal,thatprovidesanalternativethatmaybeappliedwhereneededacrosstheCentralValleyRegion;and(b)implementationoftheSanJoaquinRiverReal‐TimeManagementProgramwithintheSanJoaquinRiverwatershed.

SSALTSdemonstratedthatimplementationofin‐valleyalternativescanprovideshort‐termorlocalsolutionstothemanagementortreatmentofsalttoensurelocaldrinkingwatersuppliesarenotimpactedandlocaldegradationisminimizedordoesnotoccur(CDMSmith2014).TheseoutcomesareappropriateinareasoftheCentralValleyRegionwheresalinityingroundwaterisnotasignificantconcern.However,wheresaltaccumulationisasignificantconcern,i.e.,salinityisalreadyelevated,istrendingupwardandhasthepotentialtoimpactthebeneficialuse,orthebeneficialuseisalreadyimpacted.Currentsalinitymanagementactivitiesmayonlyaddress


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about15%oftheannualsaltload.Long‐termsolutionsareneededtoaddresstheother85%.Accordingly,implementationof,orparticipationin,along‐termsalinitymanagementprogrambydischargersandotheraffectedentitieswillbenecessary.Wherealong‐termmanagementprogramisnecessary,SSALTSrecommendedthedevelopmentofaCentralValleyregulatedbrinelinetotransportsalttotheoceanfordisposal.Thisfindingisconsistentwithpreviousfindingsintheregionthatidentifiedtheneedfora“valleywidedrain”totransportsaltsoutoftheTulareandSanJoaquinRiverBasins.29

Similartonitrate,thetimeandcosttoachievesaltbalance(sonoadditionaldegradationoccursinareasofconcern),ormanagedrestorationissignificant,especiallywithinareasofthesouthernpartoftheCentralValley.Forexample,thecapitalcosttodesignandconstructaCentralValleyregulatedbrinelinetodischargebrinetoSanFranciscoBaywouldbemorethan$7billionplusanadditional$0.7‐$0.8billion(in2014dollars)tooperateandmaintainthesystem(CDMSmith2014).Thesecostsdonotincludethepipelinesrequiredtocollecteffluentsfortreatment.Oncetreatmentandbrinedisposalsystemsareoperational,treatedwatercouldbesoldtooffsetannualimplementationcosts.Thesecostsweredevelopedbasedonaconceptualapproachtothedevelopmentofabrineline.Costswouldvarydependingonactualoutfalllocation,systemconfigurationandenvironmentalpermittingwhichwillbechallenging.

SSALTSprovidedaconceptuallevelviewofthechallengesthatwillbefacedintheCentralValleytoachievesaltbalanceandultimatelyrestoration,bothwhereitisdeemedreasonableandfeasible.Notonlyaretheresignificantengineeringandpermittingchallengestoidentifiedsolutions,buttherearesignificantfundingandgovernanceissuestobeaddressed(CDMSmith2016b).Withtheseuncertaintiesinmind,CV‐SALTSdevelopedaSalinityManagementStrategythatestablishedaphasedapproachtosaltmanagementwherethefirstphase,expectedtorequireapproximately10‐15yearstocomplete,wouldfocusonaddressingthekeygovernanceandfundingissuesassociatedwithlong‐termsaltmanagement,andconductingtheadditionaltechnicalstudiesneededtofurtherdevelopshort/long‐termsolutionsforsaltmanagementatregionalandsubregionalscales(seeAttachmentA‐3andSection4.3.3below).Thesecondandthirdphaseswouldseekfundingforandimplementthesaltmanagementprogram.

4.2.5.3 Alta Irrigation District Management Zone Archetype

TheSNMPincludesaproposedGroundwaterManagementZonePolicy(AttachmentA‐1)toencouragetheestablishmentofmanagementzonesasarecommendedapproachforregionalmanagementofnitratewithingroundwaterbasins/subbasins.Tofacilitatethedevelopmentofthispolicy,CV‐SALTScommissionedtheManagementZoneArchetypeAnalysis:AltaIrrigationDistrictstudy(LarryWalkerAssociatesetal.2016)toevaluateanumberofissuesthatmightaffectthedevelopmentandimplementationofamanagementzone.

TheconceptualmanagementzoneforthestudywastheAIDwithintheKingsgroundwatersubbasinThestudy,whichwasdevelopedandimplementedinacollaborativesettingwithlocalstakeholders,includingregulatoryandpartneragencies,servedasanexampleand“proofofconcept”tohelptest,onaspatiallyrefinedbasis,theapplicationofselectedpolicies,dataanalysismethods,andsaltandnitratemanagementapproachesunderconsiderationbyCV‐SALTS.Local

29TLBBasinPlan,Pg.IV‐5‐6;SRSJRBasinPlan,Pg.IV‐15.00

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Section 4 Central Valley Salt and Nitrate Management Strategy saltandnitratemanagementgoalsfortheAIDmanagementzonearchetypeweredevelopedbytheAIDstakeholdersearlyintheprojectandwerefocusedonthehighestpriorityissueswithinthearea,includingsupportingsustainablemanagementofsurfacewaterandgroundwatersuppliesandprotectingsurfacewaterandgroundwaterqualityandbeneficialuses.

Thelocalgoalsassistedthestakeholdersinprovidingacontextwithinwhichtotestthevarioussaltandnitratemanagementoptionsand/orpoliciesthatcouldbeestablishedfortheconceptualmanagementzone.AnanalysisoffourmanagementscenarioswasperformedusingtheAIDmanagementzonemodeltoevaluatetheeffectsofvariousstrategiesformanagingsaltandnitrateintheAIDmanagementzone.Threeofthesemanagementscenariosvariedfactorssuchasirrigationefficiency,rechargeandnitrogenloading.Thefindingsfromthesevariousscenariosshowedthatsaltandnitrateconcentrationsdidnotimprovesignificantlyoverdifferenttimeperiods(5,10,20,30,40,5075and100years).Infact,waterqualitydeclinedinsomecasesalegacysaltandnitrateloadsmovedthroughthegroundwater.Afourthmanagementscenariowasevaluatedthatwasmuchmoreaggressiveinitsimplementation.Calledthe“extremescenario”thisscenarioremovedallagricultural‐relatedmassloadingofnitrogenintheAID.Basedonthemodelingresultsfromimplementationofthisscenario,improvementofsimulatednitrateconcentrationsoccurredinallgroundwaterzonesovertime,butatthesametimedegradationofsimulatedTDSconcentrationsoccurred(LarryWalkerAssociatesetal.2016,seeAppendixE).

TheworkperformedundertheAIDstudyprovidedvaluableinformationtoinformthisSNMP.Importantly,thestudydemonstratedthatattainmentofwaterqualityobjectives,i.e.,achievingrestoration,inambientgroundwatermaynotalwaysbepossible,assimilativecapacitymaynotbeavailable,andmanagementphilosophiesmayvaryamongstakeholders.WhilethefindingsfromthestudymaynotnecessarilytranslatetoallareasoftheCentralValley,giventhediversityofgroundwaterconditions,thebasicmethodologyforcharacterizingconditions,performingdataanalysis,developingandusingpredictivemanagementmodels,andthedevelopmentofappropriatemanagementstrategiessuitedtolocalrealitiesmaybecrossapplied.ThesefindingswillprovidesupporttotheimplementationoftheGroundwaterManagementZonePolicyrecommendedunderthisSNMP(seeAttachmentA‐1).

4.2.5.4 Salt and Nitrate Conditions

Section6b(3)(d)oftheRecycledWaterPolicyidentifiesthetechnicalcomponentsrequiredforinclusionintheSNMP:“Saltandnutrientsourceidentification,basin/subbasinassimilativecapacityandloadingestimates,togetherwithfateandtransportofsaltsandnutrients.”CV‐SALTScompletedanumberofstudiestodevelopthisinformationintheCentralValleyandthefindingsfromthesestudiesprovidethefoundationforthenitrateandsaltmanagementsectionsofthisSNMP(Sections4.3.2and4.3.3,respectively).Table4‐3summarizesthestudiesthatprovideinformationoneachRecycledWaterPolicyrequiredcomponentandwherethatinformationissummarizedwithinthisSNMP.AttachmentBofthisSNMPprovideslinkstoadditionalinformationregardingstudiescompletedtofulfilltherequirementsoftheRecycledWaterPolicy.


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Table 4‐3. CV‐SALTS Technical Studies Completed to Satisfy Recycled Water Policy SNMP Requirements for the Evaluation of Salt and Nitrate

Required Recycled Water Relevant CV‐SALTS Studies1

Policy Component Salt and nutrient (nitrate)

source identification

Larry Walker Associates et al. 2013. Initial Conceptual Model Final Report:

Task 7 and 8 ‐ Salt and Nitrate Analysis for the Central Valley Floor and a

Focused Analysis of Modesto and Kings Subregions. December 2013.

Larry Walker Associates et al. 2016. Management Zone Archetype

Analysis Report: Alta Irrigation District. July 2016.

CDM Smith. 2016a. Nitrate Implementation Measures Study. March 2016.

CDM Smith 2013 and 2014. SSALTS Final Phase 1 Report: Identification

and Characterization of Existing Salt Accumulation Areas; and Final Phase

2 Report: Development of Potential Salt Management Strategies.

December 2013 and October 2014, respectively.

Basin/subbasin assimilative

capacity




Luhdorff & Scalmanini Consulting Engineers and Larry Walker Associates.

2016a. Region 5: Updated Groundwater Quality Analysis and High

Resolution Mapping for Central Valley Salt and Nitrate Management Plan;

July 2016.

Basin/subbasin loading

estimates




Fate and transport of salts

and nutrients (nitrate)




Implementation measures to

manage salt and nutrient

loading in the basin on a

sustainable basis

CDM Smith. 2016b. SSALTS Final Phase 3 Report: Evaluate Potential Salt

Disposal Alternatives to Identify Acceptable Alternatives for

Implementation. October 2016.

CDM Smith. 2016a. Nitrate Implementation Measures Study. March 2016.

CDM Smith. 2014. SSALTS Final Phase 2 Report: Development of Potential

Salt Management Strategies. October 2014.

CDM Smith 2013. SSALTS Final Phase 1 Report: Identification and

Characterization of Existing Salt Accumulation Areas. December 2013.

Luhdorff & Scalmanini Consulting Engineers and Larry Walker Associates.

2016b. Alta Irrigation District Management Zone: Aggressive Restoration

Alternative Modeling Scenario Results. Technical memorandum prepared

for CV‐SALTS. September 2016.

Larry Walker Associates et al. 2016. Management Zone Archetype

Analysis Report: Alta Irrigation District. July 2016. 1 See Section 7 for complete references; referenced CV‐SALTS studies may be accessed through Attachment B or at: http://www.cvsalinity.org/index.php/committees/technical‐advisory/technical‐projects‐index.html

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4.3 Salt and Nitrate Management Strategy ThissectionrepresentstheCentralValleySNMPstrategytomanagesaltandnitrate.AlldischargerswithanexistingWDR/ConditionalWaiverorthoseseekinganewWDR/ConditionalWaivershallcomplywiththerequirementsestablishedbelowforthemanagementofnitrateandsaltfordischargestogroundwater.

4.3.1 Management Plan Framework ForplanningpurposestosupportdevelopmentofthisSNMPthegroundwaterbasins/subbasins,ascurrentlyestablishedbyDWRfortheCentralValley(DWR2003),serveasthebasicordefaultunitsfortheevaluationofsaltandnitrateintheCentralValleyRegion.SNMPSections3.2and3.3abovesummarizedtheexistingTDSandnitratewaterqualityconditionswithineachofthesebasinsandsubbasins.Section3.3.2.3(seeTable3‐17)providesthedefaultassimilativecapacityforupperorproductionzonesforTDSandnitratetoprotectbeneficialuses.Thesedefaultassimilativecapacityfindingsarebasedonthefollowingthresholds:Nitrate(asN)‐10mg/L;TDS–1,000mg/L(EC1,600µg/L).Absentanyotherinformation,theCentralValleyWaterBoardwillrelyonthewaterqualityfindingspresentedinSection3asthebasisfordevelopingsaltandnitratemanagementrequirementsinWDRs/ConditionalWaivers. Itisrecognizedthatthedefaultvaluesforexistingwaterqualityconditionsorassimilativecapacityappliedtoanentiregroundwaterbasinorsubbasindoesnotconsidervariabilityinsaltandnitrateconcentrationsatthelocal/subregionallevel(e.g.,seegroundwaterbasins/subbasinfiguresinLuhdorff&ScalmaniniConsultingEngineersandLarryWalkerAssociates2016a).Accordingly,thisCentralValleySNMPprovidestheopportunityforanindividualdischarger,dischargerspermittedunderaGeneralOrder,ordischargersthathaveformedamanagementzonetoprovidesupplementalinformationthatsupersedesorreplacesthedefaultrequirementsestablishedbythisSNMP.Therequirementsfordevelopingthedata/informationtosupplementorsupersedethedefaultrequirementsofthisSNMParediscussedbelowinSection4.3.4.

4.3.2 Nitrate Management Nitratemanagementwillbeimplementedasdescribedinthesectionsbelow.AttachmentsA‐1(GroundwaterManagementZonePolicy),A‐2(NitratePermittingStrategy),andA‐4(ExceptionsPolicy)provideadditionalsupportinginformation.

EffortstomanagenitratetomeetthegoalsofthisSNMPwillbeimplementedinWDRsorotherappropriateBoardordersthatmustimplementrelevantprovisionsoftheBasinPlans,orConditionalWaivers,whichmustbeconsistentwiththeBasinPlans.30Withrespecttonitrate(ascurrentlyimplementedundertheBasinPlans),WDRs/ConditionalWaiversmustensurethatthatthereceivingwaterwillmeetthewaterqualityobjective,orthatthedischargewillnotcauseorcontributetoanexceedanceofanapplicablewaterqualityobjective.Inaddition,theissuanceofWDRs/ConditionalWaiversmustalsobeconsistentwithrelevantstateandregionalpolicies.InsomeareasoftheCentralValley,andforsometypesofdischargers,thetraditionalpermittingapproachfornitratesmaynotbefeasible,reasonableorpracticable.ThisSNMPsetsforththe

30WaterCode§13263&13269


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nitratemanagementapproachmovingforward,consistentwiththerecommendationscontainedwithinthepoliciesandguidanceprovidedinAttachmentA.

4.3.2.1 Overview of the Nitrate Permitting Strategy

Permitting Pathways

TheSNMPimplementationapproachforpermittingnitratedischargestogroundwaterisseparatedintotwopaths:

PathAdescribestheproposedapproachwhenanindividualdischarger(orthirdparty

groupsubjecttoaGeneralOrderwishingtoproceedunderPathA)decidestocomplywiththenitratecomponentsoftheSNMPasanIndividual/ThirdParty,orwherethereisnomanagementzone.ThispathwayfollowsmorecloselywiththeCentralValleyWaterBoard’straditionalpermittingapproach,withsomeadditionalflexibility.

PathBdescribestheproposedapproachwhenanindividualintendstoparticipateinamanagementzoneinordertocomplywiththenitratecomponentsoftheSNMP.TheSNMPencouragesdischargerstoparticipateinmanagementzonesasthepreferredmethodforcomplyingwiththenitratecomponentsoftheSNMP.However,participationinamanagementzonemaynotbeappropriateforeverydischarger,orgroupsofdischargers,dependingonlocalwaterqualityandvariousdischargerrelatedcircumstances.

Notably,forthosedischargersintendingtocomplyviaPathA,assimilativecapacitymaybegrantedbytheCentralValleyWaterBoardsubjecttorequiredfindings,butassimilativecapacitymustbeavailableinshallowgroundwater31(seeSection4.3.2.3belowfordiscussionregardingassimilativecapacity),withsomelimitedexceptions.Incontrast,fordischargersintendingtocomplybyparticipatinginamanagementzone(i.e.,PathB),assimilativecapacitymaybegrantedbytheCentralValleyWaterBoard(againsubjecttorequiredfindings).InthiscaseitisrecommendedthattheCentralValleyWaterBoardevaluatetheavailabilityofassimilativecapacityusingavolume‐weightedaverageintheupperzone.

Early Action Plans (EAP)

RegardlessofwhetheradischargerchoosesPathAorB,alldischargersmustassessnitratelevelsingroundwaterusedforMUNthatmaybeimpactedbynitrateintheirdischarge(s)toensureitisasafe,reliablesourceofdrinkingwaterwithrespecttonitrates.Ifimpacted,andwherethedischargeriscausingorcontributingtoanexceedanceofnitrateinthegroundwater,thenthedischargershallsubmitanEAPthatincludesspecificactionsandascheduleofimplementationtoaddresstheimmediateneedsofthosedrinkinggroundwaterfrompublicwatersupplyordomesticwellsthatexceedthedrinkingwaterstandardfornitrate.ThetimingofthesubmittaloftheEAPdependsonwhetheradischargercomplieswiththisSNMPasanindividualdischarger(PathA)oraspartofamanagementzone(PathB).

31Theshallowestportionwithintheupperzone(e.g.,uppermost10%oftheupperzone)andwheregroundwaterwouldbeconsideredtoconstituteanaquifer(whichisdefinedasa“bodyofrockorsedimentthatissufficientlyporousandpermeabletostore,transmit,andyieldsignificantoreconomicquantitiesofgroundwatertowellsandsprings”[DWR,2003]).Inallcases,relevantgroundwaterdoesnotincludeperchedwater.


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Prioritization of Implementation

ConsideringthesizeoftheCentralValleyRegion,andthevaryingdegreeofnitrateconcentrationsfoundingroundwaterbasins/subbasinsthroughouttheregion,itisimpracticalandunreasonabletoexpectthatthenitratemanagementrequirementswillbeimplementedbyeveryone,everywhere,atthesametime.Rather,itisappropriateforthisSNMPtorecommendaninitialpriorityrankingofgroundwatersubbasinsandtimescheduleforimplementationofthenitratemanagementrequirements.TherecommendedprocessalsoprovidestheCentralValleyWaterBoardthediscretiontoconsiderwaterquality‐basedfactors,andotherrelevantinformation,toadjustitsdeterminationofareasthatshouldbeprioritizedfirstforimplementationofthenitraterequirementsand/oridentifyareasthatwouldbeconsideredlowerpriority.Ingeneral,theprocessisdescribedasfollows:

Step1–Thisstepidentifiedspatiallyhigherpriorityareasatbothonesquaremilegridandaggregatelevel(groundwaterbasin/subbasin)scales.Theidentificationofhigherpriorityareasreliedontheuseofambientnitratewaterqualitydatafortheupperzoneingroundwaterbasins/subbasins.Notably,theidentificationofpriorityareasbasedonavailablewaterqualitydataandatthislargeofascalemaynotaccuratelyportraywhichareasinabasin/subbasinaretrulyatriskfornitratecontaminationindrinkingwater.Therefore,itisappropriatefortheCentralValleyWaterBoardtohavediscretiontoadjusttheinitialfindingsbasedonadditionalfactors/criteriaandinformation.

Step2–Torevisetheinitialwaterquality‐basedprioritizationinStep1forthegroundwaterbasin/subbasins,theCentralValleyWaterBoardhasthediscretiontoconsideradditionalinformationandfactorswhenidentifyingpriorityareasforimplementationofnitraterequirements.Thisdiscretionincludesidentifyingpriorityareasthataresmallerportionsofalargergroundwaterbasin/subbasinidentifiedinStep1,or re‐prioritizingallorpartsofalargerbasin/subbasin.Theadditionalfactorsinclude,butarenotlimitedto:(a)considerationofthewaterqualitydatathatwasreliedonandthattriggeredthepriorityrankingintheSNMP;(b)ifmorerecentdataand/orinformationareavailableorhasbeenprovidedthatbetterindicatesifthearea(orasubarea)inquestionisatriskfornitratecontaminationindrinkingwatersupplies;(c)ifgroundwateristhepredominatesourceofdrinkingwaterorifsurfacewatersuppliesarethemajorsourceofdrinkingwater;and(d)thedirectimpactonconsumers.

TheSNMPrecommendsthatimplementationbeginonthefirsttierofprioritygroundwaterbasins/subbasinswithinoneyearoftheeffectivedateoftheBasinPlanamendmentsadoptedtoimplementthisSNMPandwithintwotofouryearsoftheeffectivedateforthesecondtierprioritygroundwaterbasins/subbasins.AreasnotprioritizedwithinthefirsttwotierswillstillneedtocomplywiththeSNMPnitraterequirementsinthefuture,butimplementationofsuchrequirementsshallbephasedinbytheCentralValleyWaterBoardasresourcesallow.

Basedonthisgeneralprioritizationframeworkdescribedabove,followingisadditionalinformationregardinghowtheSNMPhasinitiallyidentifiedhigherpriorityareasforSNMPimplementation(Step1),andthefactorsandtimingforsubmittalofadditionalinformationthatmaybeconsideredunderStep2toadjusttheprioritizedlistandscheduleofareastargetedforimplementation.

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Step1‐InitialPrioritizationUsingWaterQualityDataTocompletetheinitialprioritizationofgroundwaterbasins/subbasins,theSNMPreliedontheuseof2000‐2016nitrateconcentrationdatafromwellscompletedintheupperzone(Luhdorff&ScalmaniniConsultingEngineersandLarryWalkerAssociates2016a)(SeeSection3.3).Wherenowelldatawereavailable,nitrateconcentrationswereinterpolatedfromnearbyareas.Estimatednitrateconcentrationvaluesintheupperzonewereassessedatonesquaremilegridandgroundwaterbasin/subbasinscalesusingthemethodologydescribedinSNMPAttachmentD‐4.Table4‐4belowliststheresultingInitialPrioritizationScoresfortheCentralValleyfloorgroundwaterbasins/subbasins.Basedonthesescores,CV‐SALTSdevelopedarecommendationforwhichbasins/subbasinsshouldbeprioritizedasPriority1and2–thefirsttwotiersrecommendedforimplementation(Table4‐4).

Step2–AdditionalAnalysisTheCentralValleySNMPrecommendsthattheCentralValleyWaterBoardhavethediscretiontoconsideradditionalfactorsandinformationtoadjusttheprioritizedbasins/subbasins,orpartsofthereof,andscheduleforimplementingthenitraterequirementsinthoseprioritizedareas.Inexercisingthisdiscretion,theCentralValleyWaterBoardmayconductthisadditionalanalysisunderitsowninitiative,oruponreceivinginformationrelativetothefactorsidentifiedbelowbyanyinterestedpersons.Further,theCV‐SALTSExecutiveCommitteemaycontinuetoevaluateadditionaldataandinformationbasedonthefactorsidentifiedbelow,andmayprovidetheCentralValleyWaterBoardwithanupdatedrecommendationforprioritizationinthefuture.Anysuchrecommendationorrequestforre‐prioritizationfromtheCV‐SALTSExecutiveCommitteeoranyinterestedpersons,needstobeprovidedtotheCentralValleyWaterBoardpriortothecloseofanypubliccommentperiodrelatedtheCentralValleyWaterBoard’sadoptionofBasinPlanamendmentstoimplementtheSNMP.Theadditionalfactorsincludebutarenotlimitedto:

(a)Degreetowhichareas(orsubareas)withknowndrinkingwatersupplycontaminationingroundwaterintheupperzoneingroundwaterbasins/subbasinswillbeaddressedinatimelymannerthroughthecurrentorderofprioritybasedonwaterqualityfactorsalone(Table4‐4).

(b)Additionaldata/informationprovidedbydischarger(s)and/orotherstakeholderswithinabasin/subbasin(orsubarea)thatdemonstratesthatthenitrateconcernsasidentifiedinTables4‐4havebeenaddressedorwillbeaddressedviaanotherprogramoractivity.

(c)Additionaldata/informationprovidedbydischarger(s)and/orotherstakeholderswithinabasin/subbasin(orsubarea)thatdemonstratesthattherankinginTable4‐4isnotrepresentativeofgroundwaterdrinkingwaterconditionsandthatthebasin/subbasin(orsubarea)doesnotneedtobeprioritizedbecausetherearenotconcernsorrisksfornitratecontaminationtobefoundingroundwaterreliedonfordrinkingwaterpurposes.

(d)Degreetowhichtheareaidentifiedasahigherprioritybywaterqualityfactorsactuallyhasimpacteddrinkingwaterusers(i.e.,drinkingwaterispredominatelyasurfacewatersupply,ordrinkingwatersuppliesareprimarilygroundwater).

(e)Changesingroundwaterbasin/subbasinboundariesbyDWR,whichmayaffectthespatial

orderaspresentedinTable4‐4.

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Table 4‐4. Ranking and Priority for Groundwater Basins/Subbasins Based on Step 1 of Prioritization Process Using Ambient Nitrate Concentrations in the Upper Zone (see text)1

2 Groundwater Basin/Subbasin (DWR Bulletin 118) Initial Prioritization

Priority Number Name 3

Score

Priority 1

5‐22.11 Kaweah 5.35

5‐22.03 Turlock 4.27

5‐22.05 Chowchilla 3.78

5‐22.13 Tule 3.48

5‐22.02 Modesto 3.09

5‐22.08 Kings 3.02

Priority 2

5‐21.67 Yolo 2.89 5‐22.04 Merced 2.76

5‐22.14 Kern County (Westside South) 2.70

5‐22.12 Tulare Lake 2.44

5‐22.14 Kern County (Poso) 2.37

5‐22.07 Delta‐Mendota 2.13

5‐22.01 Eastern San Joaquin 1.98

5‐22.06 Madera 1.93

Not Prioritized by

SNMP4

2‐4 Pittsburg Plain 1.70 5‐21.66 Solano 1.37

5‐22.15 Tracy 1.35

2‐3 Suisun‐Fairfield Valley 1.34

5‐21.52 Colusa 1.26

5‐22.14 Kern County (Kern River) 1.21

5‐21.61 South Yuba 1.03

5‐21.64 North American 0.93

5‐21.57 Vina 0.92

5‐22.16 Cosumnes 0.87

5‐21.58 West Butte 0.83

5‐21.68 Capay Valley 0.80

5‐21.62 Sutter 0.71

5‐21.56 Los Molinos 0.70

5‐22.10 Pleasant Valley 0.64

5‐21.60 North Yuba 0.63

5‐21.65 South American 0.53

5‐21.54 Antelope 0.49

5‐21.59 East Butte 0.48

5‐21.51 Corning 0.45

5‐21.50 Red Bluff 0.27

5‐21.55 Dye Creek 0.25

5‐22.09 Westside 0.18

5‐21.53 Bend 0.18

5‐6.04 Enterprise 0.10

5‐6.03 Anderson 0.08

5‐6.01 Bowman 0.04

5‐6.06 South Battle Creek 0.00

5‐6.05 Millville 0.00

5‐6.02 Rosewood 0.00 1 Water quality data source: Luhdorff and Scalmanini Consulting Engineers and Larry Walker Associates (2016a) 2 The Kern County subbasin is split into three parts to be consistent with the Tulare Lake Basin Plan 3 See SNMP Attachment D‐4 for additional information regarding use of water quality data to develop Initial Prioritization Scores 4 Areas not prioritized in Priority 1 or 2 will still need to comply with the SNMP nitrate requirements in the future, but

implementation of such requirements shall be phased in by the Central Valley Water Board as resources allow

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(f) Maximizingefficientuseofresources,whichmayaffectthenumberofbasins/subbasins(orsubareas)thatmaybeincludedontheCentralValleyWaterBoard’slistofprioritizedareas,anditsscheduleofimplementation.

TheCV‐SALTSdatabaseisthesourceofthedatausedtoestablishtheinitialprioritizationscore(Luhdorff&ScalmaniniConsultingEngineersandLarryWalkerAssociates2014).ThisdatabaseincludesdatafromallwelltypesintheCentralValleyRegion,includingthoseusedforremediationmonitoring.Assuch,acloserexaminationofthedatausedtoestimateambientnitrateconcentrationsintheupperzonemay,insomecases,bewarrantedunderStep2,butwithintheschedulerequiredformakingrecommendedchangestotheinitialprioritization(seediscussionabove).Thispotentialneedforconsiderationofadditionaldata/informationisaddressedbyfactors(b)and(c)aboveandillustratedbyanexampleinSNMPAttachmentD‐4.

RegardlessofthepriorityforimplementationandscheduleestablishedbytheCentralValleyWaterBoard,nothingpreventsadischargerorgroupofdischargersfromimplementingthenitratemanagementrequirementsintheSNMPpriortoreceivinganoticetocomply,orpreventstheCentralValleyWaterBoardfromre‐prioritizingareasinthefuturebasedonnewdataandinformation.

Management Zones

TheCentralValleySNMPrecommendsandencouragestheestablishmentofmanagementzonesfornitrateasanoptionforgroundwaterqualitymanagementatthelocalorsubregionallevel,especiallywithintheCentralValleyfloor.Figure4‐1summarizesthecharacteristicsofamanagementzone.Theestablishmentofamanagementzone,asadiscreteregulatorycomplianceunitfornitrateforthepurposesofcomplyingwiththeCentralValleyRegion’sSNMP,ismostappropriateinareaswheretheinteractionsamonglanduse,waterqualityandwaterusersarecomplexandsignificantconcernsexistwithmeetingthenitratewaterqualityobjectivesestablishedtoprotecttheMUNbeneficialusesingroundwater.Inareaswherethesecomplexitiesorwaterqualityconcernsdonotexist,establishmentofamanagementzonemaynotbethebestapproachformanagingdischargestogroundwater.Thismaybeparticularlytruefordischargerslocatedinareaswhereexistingnitratewaterqualityisgood,individualsandcommunitywatersystemsarenotimpacted,andlong‐termwaterqualitytrendsarenotaconcern.Similarly,establishmentofamanagementzonemaynotbeappropriateoutsideoftheCentralValleyfloorinthesurroundingfoothillsandvalleys.Inanyofthesesituations,compliancewiththenitratemanagementrequirementsofthisSNMPmaybebestaccomplishedthroughexistingwaterqualitymanagementprogramsimplementedthroughindividualWDRs/ConditionalWaiversor,insomecases,throughcoordinationwithlocalagenciestoenforcesourcewaterprotectionrequirements.


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Figure 4‐1. Characteristics of a Management Zone

A defined area which incorporates a portion of a larger groundwater basin(s)/subbasin(s) that serves

as a discrete regulatory compliance unit for compliance with the nitrate components of the Central

Valley SNMP;

Intended to include all of the groundwater and all of the regulated dischargers that discharge nitrate

and that choose to participate in the management zone within the land area encompassed by the

management zone boundary.

Intended, where nitrates in groundwater are impacting groundwater being used as a drinking water

supply, to facilitate the assurance of safe drinking water for all residents in an area adversely affected

by dischargers participating in the management zone, encourage stakeholder coordination and

cooperation, promote better water resource management through appropriate allocation of

resources, and provide greater regulatory flexibility where needed to prioritize nitrate management

activities and allow time to achieve compliance with the Central Valley SNMP’s nitrate management

goals.

The basis for the establishment of local management plans to manage nitrate within the

management zone’s boundary in accordance with the Central Valley Region’s overall nitrate

management goals established in the Central Valley SNMP.

Voluntarily proposed by those regulated dischargers located within the proposed management zone

boundary that have decided to work collectively and collaboratively to comply with the nitrate

management requirements of the Central Valley SNMP.

1 Dischargers within a management zone boundary that choose not to participate in the management zone, they must be able to provide assurance to the Central Valley Water Board that they are addressing any adverse effects directly or indirectly associated with their discharge.

4.3.2.2 Permitting Pathways

Figure4‐2illustratestheinitialactivitiesthatoccuruponimplementationofthenitratemanagementrequirementsofthisSNMPwithinaprioritizedarea(seeTable4‐4).WhenthedischargerswithinaprioritizedareaarenotifiedthattheymustcomplywiththisSNMP(i.e.,asdeterminedbytheprioritizationprovidedinTable4‐4),thedischargerswithinthepriorityareawillneedtodeterminewithinasetperiodoftimewhethertheyplantocomplyasanindividualdischarger(PathA)oraspartofamanagementzone(PathB).32Duringthisformulationperiod,dischargersinterestedinformingamanagementzone(oraleadentityonbehalfofdischargers)shouldworkcollectivelytodevelopaPreliminaryManagementZoneProposalthatincludestheelementssummarizedinFigure4‐3.Thetimelineforpreparationofthisproposalisasfollows:

32Forpurposesofthisnotification,individualdischargersthataresubjecttoGeneralOrdersthatcoveraspecifiedgeographicareaorarecommoditybased,andthatareadministeredbyaThirdParty(e.g.,ThirdPartyOrdersforIrrigatedAgriculture),theThirdPartymayprovidenoticeasrequiredinthissteponbehalfofitsmembers.ForindividualdischargersthataresubjecttoaGeneralOrderthatisnotadministeredbyaThirdParty(e.g.,DairyGeneralOrder),theindividualmustprovidethenecessarynoticeasindicatedinthisstep.

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FordischargerswithinPriorityArea1(seeTable4‐4),aPreliminaryManagementZoneProposalshallbesubmittedwithin270daysofthereceivinganotificationtocomplywiththenitratemanagementrequirementsofthisSNMP.Tosupportthisdeadline,CentralValleyWaterBoardshallprovidenoticetoPriority1dischargersinadvanceoftheBasinPlanamendmentsbecomingeffective.

FordischargersinPriority2,aPreliminaryManagementZoneProposalshallbeduewithinone(1)yearfromthenotificationprovidedbytheCentralValleyWaterBoard.

AreasnotprioritizedwithinPriorityAreas1or2willstillneedtocomplywiththeSNMPnitraterequirementsinthefuture,butimplementationofsuchrequirementsshallbephasedinbytheCentralValleyWaterBoardasresourcesallow.

Regardlessofthepriority,theExecutiveOfficeroftheCentralValleyWaterBoardshallretaindiscretiontoextendthetimelinesforsubmittalofaPreliminaryManagementZoneProposalifproperjustificationisprovidedtotheExecutiveOfficeratleast30dayspriortothedeadlineforsubmittingtheproposal.Similarly,theCentralValleyWaterBoardmayadjustthepriorityofanareabasedonupdatedinformation.

Figure 4‐2. Initial SNMP Nitrate Management

Actions

ThepurposeforpreparingaPreliminaryManagementZoneProposalistoprovidealldischargerswithinthespecifiedpriorityareaforadevelopingmanagementzonewithenoughinformationtomakeanelectionforcomplyingwiththenitratecomponentsoftheSNMPviaPathA(asanindividualdischarger/thirdpartygroup)orviaPathB(participantinamanagementzone).Afterconductingtheirowninitialassessmentoftheirdischarge,andafterevaluatinganyapplicablePreliminaryManagementZoneProposals,dischargerswillthenneedtonotifytheCentralValleyWaterBoardoftheirelectionofPathAorPathB.TheSNMPrecommendsthatthenotificationbemadeintheformofaNoticeofIntent(NOI).ThefollowingsectionsbelowdescribethenextstepsthatshallbeimplementedbasedontheselectionofPathAorB.

Path A ‐ Individual Dischargers or Third Party Group Subject to General Order

Figure4‐4illustratesthestepstocomplywithPathAbeginningwiththeNOIsubmittalrequirements.DevelopingpermitrequirementsunderPathAdependsontheimpactoftheindividualdischargertotheunderlyinggroundwater–measuredinshallowgroundwater.Thelevelofeffortandtheconditions/requirementsimposedbytheCentralValleyWaterBoardinpermittingnitratedischargeswillvarydependingontheimpacttowaterquality.

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Section 4 Central Valley Salt and Nitrate Management Strategy TheSNMPrecognizesthatsomedischargesofnitratestogroundwaterwouldbeconsideredlow‐threat,andarethereforerelativelysimplefortheCentralValleyWaterBoardtoauthorizeinexistingWDRs,orrenewed/revisedWDRs.Specifically,

Dischargesthatarebetterthanreceivingwaterqualityandthereceivingwaterisbetterthanthewaterqualityobjectiveof10mg/Lareconsideredtonotlowerwaterquality.Insuchcircumstances,thedischargeisnotsubjecttothestate’santidegradationpoliciesandtheCentralValleyWaterBoardisnotrequiredtomakethefindingsasspecifiedinResolution68‐16toauthorizethedischarge.

Figure 4‐3. Elements of Preliminary Management Zone Proposal

Proposed preliminary boundary areas;

Identification of initial participants/dischargers;

Identification of other dischargers and stakeholders in the management zone area that the initiating group

is in contact with regarding participation in the management zone;

Identification of process for coordinating with other non‐dischargers to address nitrate‐related drinking

water issues, which must include consideration of coordinating with affected communities, domestic well

users and their representatives, the State Water Board’s Division of Drinking Water, Local County Health

Officials, Sustainable Groundwater Management Agencies and others as appropriate;

Initial identification of public supply wells, and/or domestic wells that exceed the drinking water standard

for nitrate;

An EAP that includes specific actions and a schedule of implementation to address immediate drinking

water needs of those initially identified within the management zone boundary whose drinking

groundwater exceeds nitrate standards;

Initial assessment of groundwater conditions based on existing data and information for each basin or

subbasin covered by the management zone;

Identified constituents of concern the group intends to address with the management zone besides

nitrates (the group has the option to consider other constituents of concern, but is not required to do so);

Proposed timeline for:

o Identifying additional participants;

o Further defining boundary areas;

o Developing proposed governance and funding structure;

o Additional evaluation of groundwater conditions across the management zone boundary area, if

necessary;

o Identification of regulatory compliance pathway for participating dischargers (i.e., intend to request

approval of use of assimilative capacity that may be available on a volume‐weighted basis in the upper

zone, or need for obtaining an approved exception from meeting the nitrate water quality objective

for protection of the MUN beneficial use); and

o Preparing and submitting a Final Management Zone Proposal and a Management Zone

Implementation Plan.

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Somedischargersmaybeabletodemonstratethattheirdischarge,orcollectivedischarges,arelowthreatinnaturebecausetheyhavedataandinformationthatdemonstratesthatthedischargeshavenotdegradedgroundwateroveraspecifiedtime‐period,andthatthenatureofthedischargehasremainedconstant.Forexample,insomeareasoftheCentralValleywheregroundwaterisbetterthanthenitratewaterqualityobjective,andcroppingandculturalpracticeshaveremainedconstant,dataandinformationmaybeusedtodemonstratethelowthreatnatureofthedischarge.

Incontrast,theremaybedischargesofnitratesthatareabovethedrinkingwaterstandardandthereisnoavailableassimilativecapacity.Inthesecircumstances,itmaybeappropriatefortheCentralValleyWaterBoardtograntanexceptiontomeetingthewaterqualityobjectiveratherthanprohibitingthedischarge(seeSection4.3.2.4belowandtheExceptionsPolicyinAttachmentA‐4).Alternatively,afindingmaybemadethatthedischargewilldegradewaterqualityandanallocationofassimilativecapacityisrequired.Becauseofthevariouslevelsofimpactsthatmayresultfrom thedischarge,33this SNMPestablishesfive categoriesfordischargerschoosingtocomplywiththeSNMPviaPathA.Table4‐5defineseachofthesecategories.

Asnotedabove,Figure4‐4providesasummaryofthePathAstepstodemonstratecompliancewiththenitratemanagementrequirementsofthisSNMP.Step1intheprocessissubmittaloftheNOIwhichshallinclude:

Figure 4‐4. Path A Steps to Compliance with SNMP

Aninitialassessmentofreceivingwaterand/ordischargeconditions.

Fortraditionalpointsources,aninitialassessmenttodetermineifthedischargeisimpactinganynearbypublicwatersupplywellsordomesticwellsfornitratesbasedonallreadilyavailabledataandinformation;fornon‐pointsources,identificationofareaswherethereare“hotspots”withrespecttonitrateconcentrationsingroundwaterbasedonallreadilyavailabledataandinformation.

Asapplicable,anEAPthatincludesspecificactionsandascheduleofimplementationtoaddressimmediateneedsofthosedrinkinggroundwaterthatexceedsthedrinkingwaterstandardiftherearepublicwatersupplyordomesticwellsimpactedbynitratesfrom

33Dischargeasusedhereisintendedtomeanthequalityofthedischargeasitentersfirstencounteredgroundwater.Thus,thequalityofthedischargeitselfmayexceedthestandardbutduetotransformationandothervariables,itmeetsorisbetterthantheobjectiveasitentersfirstencounteredgroundwater.

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dischargescoveredbytheNOI.ItisanticipatedthatdischargesinCategories1through3willnotneedanEAPbecausesuchdischargesarearguablynotcausingorcontributingtoanexceedanceofthenitratedrinkingwaterstandard.Dischargesincategories4and5mayneedtoprepareanEAP,whichmaybepartofaproposedACP.AnEAPisjustthat,anidentificationofearlyactions.TheEAPmaynotbecomprehensive,andmayneedtoberevisedandsupplementedwithadditionalinformationaspartoftheACPthatisincorporateddirectlyintotheWDRs.

IdentificationofCategoryoftheDischarge(seeTable4‐5).

Informationnecessarytosupportallocationofassimilativecapacity,asapplicable(see4.3.2.3below).

ApplicationforExceptionpursuanttotheExceptionsPolicy,asapplicable(seeSection4.3.2.4belowandAttachmentA‐4).

Ifthedischarger(s)isinanareathatiscoveredbyaPreliminaryManagementZoneProposal,andthedischarger(s)isseekinganallocationofassimilativecapacityunderPathA,thedischarger(s)mustshowhowallocationofassimilativecapacitytotheindividualdischargerwillimpact(ornot)availableassimilativecapacityforthoseparticipatinginthemanagementzone.

UnderStep2(Figure4‐4),iftheNOIincludesanEAPtoaddressimmediatedrinkingwaterneeds,theCentralValleyWaterBoardwillnotifythedischargerwithin30daysifthedischargermayproceedwithimplementingtheEAP.IfnoEAPwassubmittedaspartoftheNOI,thisPathAstepisnotapplicabletothedischarger. BasedontheinformationintheNOIsubmittedinStep1,underStep3(Figure4‐4)theCentralValleyWaterBoardshalldetermineifthedischargercancomplywiththeSNMPwithnofurtheraction,orifthedischargerwillberequiredtosubmitadditionalinformationand/orifadditionalWDRconditionsarenecessaryforthedischargertocomplywiththeSNMPfornitrates.Ingeneral,perTable4‐5:

Categories1and2–ThesedischargeswillbedeterminedtocomplywiththeSNMPfornitrateswithouttheneedforfurtherconditionsorrequirements.

Category3‐TheCentralValleyWaterBoardmustmakefindingsthatareconsistentwiththe

State’sAntidegradationPolicy(ResolutionNo.68‐16).Dependingonthelevelofdegradation,theCentralValleyWaterBoardmayrequireadditionalconditionsinWDRstoimplementtheSNMP,andtoallocateassimilativecapacity,whichinthecaseofCategory3,mayconsistofadditionalmonitoringandtrendevaluations.

Categories4and5‐ToreceiveCentralValleyWaterBoardapprovalfortheallocationofassimilativecapacityorapprovalofanexceptionpursuanttotheExceptionsPolicy(seeSection4.3.2.4belowandAttachmentA‐4),thedischargerwillneedtoproposeanACPforCategories4and5aspartoftheNOI,oraccordingtoadateotherwiseagreedtobytheExecutiveOfficer.

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TomakefindingsofcompliancewiththenitratecomponentsoftheSNMP,theCentralValleyWaterBoardmustmakethefindingsand/orimposetheconditionsapplicabletoeachindividualcategory,assummarizedinTable4‐6.Thefindingsand/orconditionsshallbeincludedinanew/revisedWDR.

Table 4‐5. Discharge Categories Applicable to Path A.

Discharge Category Central Valley Water Board Findings/Conditions

Category 1 ‐ No Degradation Category

Discharge1 is equal to or less than the water quality objective of 10 mg/L, and the discharge is better than baseline receiving water quality.

Category 2 ‐ De minimus

Category

Baseline receiving water has available assimilative capacity (i.e., is better than the water quality objective). For this category, the discharge(s) may be above the water quality objective as it enters the receiving water, but the discharge(s) will use less than 10% of the available assimilative capacity over a 20‐year period and will not cause the receiving water to exceed a trigger of 7.5 mg/L in that time period. This would be considered a de minimus discharge.

Category 3 ‐ Degradation Below 75% of the Water Quality Objective Category

Discharges will be considered as part of this category if the discharge occurs in a basin where concentrations in the volume‐weighted upper zone do not exceed an acceptable annual increase2 and the discharger(s) anticipate using available assimilative capacity in baseline receiving water that is considered to be more than de minimus but will not cause the receiving water to exceed a trigger of 75% of the water quality objective for nitrate over a 20‐year planning horizon. To allow use of assimilative capacity in this circumstance, the Central Valley Water Board may find it necessary to include additional monitoring and trend evaluations as part of the WDRs in order to make appropriate findings consistent with Resolution 68‐16 and the SNMP.

Category 4 ‐ Degradation Above 75% of the Water Quality Objective Category, or Receiving Water Quality is at 50% of the water quality objective and the Discharge(s) Occur in a Basin where Concentrations in the Volume‐ weighted Average of the Upper Zone Exceeds the Acceptable Annual Increase.2

Discharges will be considered as part of this category if they anticipate using available assimilative capacity in the receiving water, and use of assimilative capacity will cause the receiving water to exceed the trigger of 75% of the water quality objective for nitrate over a 20‐year planning horizon, or the receiving water is already at 50% of the water quality objective and the discharge(s) occur in a basin where the volume‐ weighted average of the upper zone exceeds an acceptable annual increase in concentration.2 To allow use of assimilative capacity in this circumstance, the discharger must submit a proposed ACP to the Central Valley Water Board to be included as an additional condition in the WDRs in order to make appropriate findings consistent with Resolution 68‐16 and the SNMP3

Category 5 ‐ Discharge Above Objective and No Available Assimilative Capacity

Discharges that exceed the water quality objective for nitrate, and where the receiving water has no available assimilative capacity, will be considered to be part of this category. Discharges in this category will need to seek an exception pursuant to the Exceptions Policy under the SNMP. or the discharge may be prohibited

1 Discharge as used here is intended to mean the quality of the discharge as it enters first encountered groundwater. Thus, the quality of the discharge itself may exceed the standard but due to transformation and other variables, it meets or is better than the objective as it enters first encountered groundwater. 2 Acceptable annual increase: Upper zone concentrations do not increase more than 0.1 mg/L NO3‐N per year using cumulative average annual increase over a five‐year period. The cumulative average refers to an Olympic average, meaning that the highest and lowest sample results are removed; average is calculated from the remaining results. This helps address statistical outliers that otherwise may skew the results. 3 It is expected that an ACP will be required by the Central Valley Water Board if they agree to authorize use of assimilative capacity for dischargers that fall within Category 4 as an ACP will be an essential element of their ability to make the necessary findings pursuant to Resolution 68‐16. However, the Central Valley Water Board maintains the discretion to make an exception in limited and unique circumstances to authorize assimilative capacity to discharges that fall within Category 4 without an ACP but the Central Valley Water Board will still need to make all necessary findings pursuant to Resolution 68‐16.

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Table 4‐6. Summary of the Findings/Conditions Required to Demonstrate Compliance with the Nitrate Management Requirements Applicable to Path A

Discharge Central Valley Water Board Findings/Conditions

Category

Category 1

Discharge is equal to or better than the nitrate water quality objective of 10 mg/L‐N (i.e., less than 10 mg/L‐N); and, discharge is better than baseline receiving water quality.

Discharge is deemed to be in compliance with SNMP.

Category 2

Baseline receiving water quality has assimilative capacity.

Discharge(s) will not use more than 10% of available assimilative capacity over a 20‐year planning horizon and will not cause the receiving water to exceed a trigger level of 7.5 mg/L‐N over that planning horizon.

Discharge is not in a basin where the volume‐weighted upper zone concentration is increasing more than 0.1 mg/L NO3‐N per year using cumulative average annual increase over a 5‐year period.2

To determine amount of assimilative capacity consumed by the discharge, the Central Valley Water Board will consider the quality of the discharge as it enters the receiving water, accounting for reductions in nitrate mass or concentration as the discharge percolates to groundwater through the soil.1

Discharge will not unreasonably affect present and anticipated beneficial uses.

WDRs will ensure that BPTC at a level that is necessary to assure that pollution and nuisance will not occur, and that the highest water quality consistent with the maximum benefit to the people of the state will be maintained.

When the discharge is in an area that is covered by a Preliminary Management Zone Proposal, the Central Valley Water Board must consider the impact that granting available assimilative capacity to the individual under Path A will have on assimilative capacity for those that are part of the management zone.

Category 3

Baseline receiving water quality has assimilative capacity.

Discharge(s) will use more than 10% of available assimilative capacity over a 20‐year planning horizon.

Discharge will not cause the receiving water to exceed 7.5 mg/L for nitrate as N over a 20‐year planning horizon.

Discharge is in a basin where the volume‐weighted average of the upper zone is increasing more than 0.1 mg/L NO3‐N per year using cumulative average annual increase over a 5‐year period.2

To determine amount of assimilative capacity consumed by the discharge, the Central Valley Water Board will consider the quality of the discharge as it enters the receiving water, accounting for reductions in nitrate mass or concentration as the discharge percolates to groundwater through the soil.


WDRs will result in BPTC at a level that is necessary to assure that pollution and nuisance will not occur, and that the highest water quality consistent with the maximum benefit to the people of the state will be maintained.


Additional monitoring and periodic trend evaluation conditions are imposed to ensure compliance with SNMP.

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Discharge Central Valley Water Board Findings/Conditions

Category

Category 4

Receiving water quality has assimilative capacity.

Discharge(s) will use more than 10% of available assimilative capacity over a 20‐year planning horizon.

Discharge will cause the receiving water to exceed 75% of the water quality objective for nitrate (i.e., 7.5 mg/L‐N) but will not cause receiving water to exceed the water quality objective for nitrate over a 20‐year planning horizon; or the receiving water is at or above 50% of the water quality objective and the volume‐weighted average in the upper zone is exceeding an acceptable annual increase in concentration.2

To determine amount of assimilative capacity consumed by the discharge, the Central Valley Water Board will consider the quality of the discharge as it enters the receiving water, accounting for reductions in nitrate mass or concentration as the discharge percolates to groundwater through the soil.


WDRs will result in BPTC at a level that is necessary to assure that pollution and nuisance will not occur, and that the highest water quality consistent with the maximum benefit to the people of the state will be maintained.


Discharger are required to develop and implement an ACP for the nitrate components of the SNMP, which shall include the following:

- Identification of nitrate related drinking water supply issues in the area impacted by the discharge(s);

- Time schedule with milestones for addressing newly‐identified nitrate related drinking water supply issues in the area impacted by the discharge(s);

- Preliminary identification of the steps that will be taken to evaluate actions necessary to implement Management Goals 2 and 3, where reasonable and feasible, which may be phased in over time and will likely require further evaluation and assessment to identify proposed long‐term actions.

Category 5

Receiving water has no assimilative capacity for nitrates in First Encountered Groundwater.

Discharge exceeds the water quality objective for nitrate.

No reasonable, feasible or practicable means are available for discharger to comply with WDRs that would otherwise limit the discharge of nitrate to groundwater concentrations to less than 10 mg/L‐N.

It is infeasible, impracticable or unreasonable to prohibit the discharge.

Discharger required to develop and implement an ACP for the nitrate components of the SNMP, which shall include the following:

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Discharge

Category Central Valley Water Board Findings/Conditions

Category 5

(continued)

- Identification of nitrate related drinking water supply issues in the area impacted the discharge(s);

- Time schedule with milestones for addressing newly‐identified nitrate related drinking water supply issues in the area impacted by the discharge(s);

- Preliminary identification of the steps that will be taken to evaluate actions necessary to implement Management Goals 2 and 3 where reasonable and feasible, which may be phased in over time and will likely require further evaluation and assessment to identify proposed long‐term actions.

Discharger required to seek and obtain an exception in accordance with the Exceptions Policy.

1 In making this determination, the Central Valley Water Board shall consider information provided by the discharger that demonstrates that the level of nitrogen entering the receiving water is different than the level of nitrates in the discharge due to naturally occurring groundwater recharge, nitrogen transformation and losses, and nitrogen up take by plants. 2 Acceptable annual increase: upper zone concentrations do not increase more than 0.1 mg/L NO3‐N per year using cumulative average annual increase over a five‐year period. The cumulative average refers to an Olympic average, meaning that the highest and lowest sample results are removed; average is calculated from the remaining results. This helps address statistical outliers that otherwise may skew the results.

Path B – Participants in a Management Zone

PathBisforthosedischargersthatdesiretoworkcollectivelytocomplywiththeSNMPbyparticipationinamanagementzone.AfteranareaisactivatedforSNMPimplementationbasedonpriority,dischargersareencouragedtoworktogethertodevelopthePreliminaryManagementZoneProposaldescribedinFigure4‐3.Followingsubmittalofthisproposal(seeabovefortimeallowedtosubmit),dischargersthathaveselectedPathBwillcontinuetoimplementthisSNMPperthestepsillustratedinFigure4‐5,beginningwithafilingofanNOI.

Step1‐SubmittalofNoticeofIntent–Within60daysofavailabilityofaPreliminaryManagementZoneProposalforaspecifiedarea,dischargerswithinthatareathatintendtocomplywithPathB,shallsubmitanNOItotheCentralValleyWaterBoardthatincludes:(a)identificationofthemanagementzoneinwhichthedischargerintendstoparticipate,and(b)acknowledgementthattheyhavereviewedandunderstandthecommitmentsassociatedwithparticipationinthemanagementzonebasedonthePreliminaryManagementZoneProposalthatappliestotheirareaofdischarge.Ifanydischargerswithintheareaproposedforamanagementzonedecidenottoparticipateinthemanagementzone,theymustcomplywiththerequirementsspecifiedforPathA.

Step2–ImplementationofEAPandFinalManagementZoneProposal‐Aspartofparticipatinginamanagementzone,dischargerswillneedtocollectivelyberesponsibleforimplementingtheEAPthatwassubmittedaspartofthePreliminaryManagementZoneProposal.ThetimeforbeginningtoimplementtheEAPshallbebasedonCentralValleyWaterBoardacceptanceoftheEAP,whichshallbeindicatedthroughanoticetoproceedfromtheCentralValleyWaterBoardtotheleadentityresponsibleforthemanagementzoneWithin60daysaftersubmittalofthePreliminaryManagementZoneProposaltothe

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CentralValleyWaterBoardandifnoobjectionstotheEAPareprovidedinwritingbytheCentralValleyWaterBoard,themanagementzonemustbeginimplementingtheEAP.Further,althoughWDRsfordischargersparticipatinginamanagementzonewillnotyetberevisedatthisstepintheprocess,theSNMPrecommendsthattheCentralValleyWaterBoardfindparticipatingdischargersincompliancewithnitratecomponentsoftheSNMPaslongastheparticipantistimely,andingoodfaith,participatinginthemanagementzone.ParticipatinginthemanagementzoneincludesassistingintheimplementationoftheEAP,andassistingindevelopingtheFinalManagementZoneProposal.FordischargersthataresubjecttoaGeneralOrderasamemberofaThirdPartyGroup,ThirdPartyGroupparticipationonbehalfofitsmembersshallconstitutedischargerparticipation.ThirdPartyGroupsshallmakeallreasonableeffortstoinformitsmembersofparticipationinanyGroundwaterManagementZone.

Withina180daysaftersubmittalofaPreliminaryProposal,themanagementzonemustsubmitaFinalManagementZoneProposal.Figure4‐6summarizestherequirementsforaFinalManagementZoneProposal(seealsoGroundwaterManagementZonePolicyinAttachmentA‐1).

Figure 4‐5. Path B Steps to Compliance with SNMP

Figure 4‐6. Minimum Requirements for Final Management Zone Proposal

Timeline for development of a Management Zone Implementation Plan.

Updated list of participants.

Governance structure that, at a minimum, establishes the following: (a) roles and responsibilities of all

participants; (b) funding or cost‐share agreements to implement short term nitrate management

projects/activities;1 and (c) a mechanism to resolve disputes among participating dischargers.

Additional evaluation of groundwater conditions across management zone area for each basin/subbasin

covered, if necessary.

Identification of proposed approach for regulatory compliance (i.e., use of assimilative capacity and/or

seeking approval of an exception for meeting nitrate water quality objectives).

Explanation of how the management zone intends to interact and/or coordinate with other similar efforts

such as those underway pursuant to the SGMA.

1 If future legislative efforts result in the development of funds available for addressing short term and/or long term nitrate drinking water issues, the Final Management Zone proposal may include and/or indicate how use of such funds are coordinated to address nitrate drinking water related issues that would otherwise be the responsibility of the management zone participants.

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TheFinalManagementZoneProposalshallincludeatimelineforpreparationofadetailedManagementZoneImplementationPlanandindicateifthemanagementzoneisseekingcompliancethroughtheallocationofassimilativecapacityasallowedintheGroundwaterManagementZonePolicy,orthroughanexceptiontomeetingthewaterqualityobjectivefornitrateassetforthintheExceptionsPolicy(AttachmentA‐4).Figure4‐7summarizestheminimumrequirementsfortheManagementZoneImplementationPlan.

Step3‐RevisionofWDRs/CompliancewithSNMP–TheCentralValleyWaterBoardwillreviseWDRs/ConditionalWaiversforthosedischargersparticipatinginthemanagementzoneafterreceivingtheFinalManagementZoneProposal.RevisionstorelevantWDRs/ConditionalWaiversmayoccurindividually,orthrougharesolutionthatamendsallapplicableWDRs/ConditionalWaivers.UpontimelysubmittaloftheFinalManagementZoneProposal,dischargersidentifiedasbeingparticipantsofthemanagementzoneshallbedeemedtobeincompliancewithnitraterequirementsinindividualWDRs/ConditionalWaiversaslongasthedischarger(a)continuestobeanactiveparticipantinthemanagementzone;and(b)themanagementzoneismeetingidentifiedtimelinesandmilestonesinatimelymanner,includingimplementationoftheEAP.

BeforetheCentralValleyWaterBoardmaymodifyanyWDRstoincorporatetheuseofassimilativecapacityonamanagementzonebasisortoadoptanexceptiontomeetingawaterqualityobjectiveinaWDRforadischargerparticipatinginthemanagementzone,theCentralValleyWaterBoard’sExecutiveOfficermustapprovetheestablishmentofthemanagementzoneanditsimplementationplanafterprovidingpublicnoticeandopportunitytocomment.PriortoapprovalofamanagementzoneandaManagementZoneImplementationPlan,theCentralValleyWaterBoardmayadoptand/ormodifyWDRstoincludetimeschedulesthatallowdischargersparticipatinginamanagementzoneanappropriateamountoftimebeforebeingrequiredtocomplyimmediatelywithlimitationsrelateddirectlytonitratewaterqualityobjectives.ExecutiveOfficerapprovalofthemanagementzoneinnowaychangestherequirementthatanymodificationstoWDRsmustbeapprovedbytheCentralValleyWaterBoardafterpublicnoticeandhearing.

4.3.2.3 Allocation of Assimilative Capacity

Overall,theSNMPrecommendsthattheCentralValleyWaterBoardbepredisposedtoallocateassimilativecapacity,andallowlowerwaterquality,wheredoingsoassuresasignificantlybetteroutcomeforthepeopleofCaliforniathanwouldrequiringstrictcompliancewithdefaultwastedischargerequirements.Further,theSNMPrecommendsthattheCentralValleyWaterBoardprioritizeallocationsofassimilativecapacitywhenandwhereitwouldprovideademonstrablymoreeffectivemeansofassuringsafedrinkingwaterthanotheravailablepermittingalternatives.However,theSNMPalsorecognizestheimportanceofprotectinghighqualitywatersandforthisreason,theSNMPrecommendstriggerstomaintainanappropriatesafetyfactortoensurethathighqualityreceivingwatersdonotexceedthewaterqualityobjectivefornitrate.

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Figure 4‐7. Minimum Requirements for Management Zone Implementation Plan

It must be consistent with the management goals of the Central Valley SNMP, including, addressing short‐term and long‐

term drinking water needs affected by nitrates, plan for achieving balanced nitrate loadings within the management zone

(to the extend feasible and reasonable), and plan for establishing a managed aquifer restoration program to restore

nitrate levels to concentrations at or below the water quality objectives to the extent it is feasible and reasonable to do

so.

The highest water quality priority within any management zone where groundwater is impaired by nitrate contamination

is the assurance that a drinking water supply that meets drinking water standards is available to all drinking water users

within the management zone boundary.

It must document collaboration with residents that are the intended beneficiaries of short and long‐term efforts to

provide safe drinking water.

Funding or cost‐share agreements, or a process for developing such funding or cost‐share agreements, to implement

intermediate and long‐term nitrate management projects/activities.1

Implementation of nitrate management activities within a management zone may be prioritized based on factors

identified in the Central Valley SNMP and the results of the characterization of nitrate conditions. Prioritization provides

the basis for allocating resources with resources directed to the highest water quality priorities first.

It shall include a water quality characterization for each basin or subbasin covered by the management zone and nitrate

management measures consistent with the requirements established in the Central Valley SNMP, including:

o Characterization of nitrate conditions within the proposed management zone which will be used as the basis for

demonstrating how nitrate will be managed within the management zone over short and long‐term periods to meet

the management goals established in the Central Valley Region SNMP.

o Short (≤ 20 years) and long‐term (> 20 years) projects and/or planning activities that will be implemented within the

management zone, and in particular within prioritized areas (if such areas are identified in the Implementation Plan)

to make progress towards attaining each of the management goals established by the Central Valley SNMP. Over

time as water quality is managed in prioritized areas, updates to the plan may shift the priorities in the management

zone.

o Milestones related to achievement of the overall Central Valley SNMP’s long‐term goal of achieving balanced nitrate loadings and managed aquifer restoration.

o A short and long‐term schedule for implementation of nitrate management activities with interim milestones.

o Identification of triggers for the implementation of alternative procedures or measures to be implemented if the interim milestones are not met.

o A water quality surveillance and monitoring program that is adequate to assure that the plan when implemented is achieving the expected progress towards attainment of management goals.

o Consideration of areas outside of the management zone that may be impacted by discharges that occur within the

management zone boundary areas.

The plan may be modified periodically to incorporate changes based on new data or information, and should generally

be changes that will benefit water quality in the management zone. Any modifications to the plan that impact or

change timelines, milestones or deliverables identified in the Implementation Plan must be approved by the Central

Valley Water Board’s Executive Officer.

Identify the responsibilities of each regulated discharger, or groups of regulated dischargers participating in the

management zone to manage nitrate within the Zone.

Include a proposed monitoring program, or in the alternative, participate in a valley‐wide and/or regional groundwater

monitoring, if appropriate.

1 Should future legislative efforts result in the development of funds specific to addressing drinking water issues, such

funding should be considered as an appropriate funding source for providing short and/or long‐term drinking water, subject

to the terms, conditions and restrictions for the funding.

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Section 4 Central Valley Salt and Nitrate Management Strategy Ingeneral,todeterminethattheallocationofassimilativecapacity“willnotresultinwaterqualitylessthanthatprescribedinthepolicies,”theSNMPrecommendsthattheCentralValleyWaterBoardrequiredischargerstodemonstratethatthepermitteddischarge(s)willnotcausetheaveragenitrateconcentrationintherelevantgroundwatertoexceed10mg/L.TheSNMPrecommendsthatrelevantgroundwaterbetheareareferredtoasshallowgroundwater(seefootnote29),orbeavolume‐weightedaveragefortheupperzones.

Withrespecttodeterminingifassimilativecapacityisavailable,thelevelofdemonstrationneededwouldvarybasedonanumberofdifferentfactors.Forexample,fordischargesfromasinglefacility(oftenreferredtoasapointsourcedischarger),thedemonstrationmayberelativelysimpleifthedischargerisseekingtoshowavailableassimilativecapacityfromlookingatshallowgroundwaterandthedischargerhasthenecessarydataandinformationtoshowthatthedischargewillnotcauseshallowgroundwatertoexceedtheestablishedtriggerlevelsovera20‐yearplanninghorizon.Attheotherendofthescale,multipledischargersseekingtoshowassimilativecapacityavailableintheupperzoneoveradefinedmanagementzoneareawilllikelyneedmoreextensivedataandinformation,and/ormodeling,tomakethedemonstrationthatestablishedtriggerlevelswillnotbeexceededwithinadefinedtimeframe.Ingeneral,theCentralValleyWaterBoardshouldnotallocateuseofassimilativecapacitybasedonavolumeweightedaverageintheupperzonethatwouldresultingroundwaterexceedingatriggerlevelof75%ofthenitratewaterqualityobjectiveovera20‐yeartimeframe,unlesstheCentralValleyWaterBoardcanproperlyfindthatuseofassimilativecapacityabovethistriggerlevelwillnotresultinpollutionornuisanceoverthelongerterm.

TheallocationsofassimilativecapacitybytheCentralValleyWaterBoardshallbedeterminedbasedonthepermittingstrategypathwaythatindividualdischargers(PathA)orgroupsofdischargers(PathB)chooserelativetonitratepermitting.Section4.3.2.2abovedescribesindetailthetwopathways,andtheallocationofassimilativecapacitythatisapplicablebasedonthepathwaythatisselected.GrantingassimilativecapacitybasedontheupperzonewouldtypicallyneedtobeaccompaniedwithaproposedACPwhilegrantingassimilativecapacityinshallowgroundwatermaynot.Notably,however,theremaybeuniquecircumstanceswheretheCentralValleyWaterBoardfindsitappropriatetoconsidertheallocationofassimilativecapacitybasedontheupperzonebutdeterminesthatanACPisnotnecessary.Forexample,insomeareasoftheCentralValley,groundwaterqualityisexcellentwithrespecttonitratesandhistoricalandpresentdataindicatesthattherearelimitedthreatstodegradationofgroundwaterqualitybasedonpastandcurrentpractices.Insuchcases,theCentralValleyWaterBoardretainsitsdiscretiontodeterminetheavailabilityofassimilativecapacityusingaveragesintheupperzonewithouttriggeringtheneedforanACP.However,inallcases,iftherearelocalized“hotspots,”dischargers’causingorcontributingtonitratelevelsinthelocalizedareamayberequiredtoproposeanACPforthatspecificarea.

WhereanACPisrequired,theproposedACPshouldbedesignedtomitigatethesignificantadverseeffect(s)ofthepermitteddischarge(s)asitrelatestonitrateforwhichanexceptionisgranted.Moreover,aspartofanACPfornitrate,discharger(s)willneedtoshowthatgroundwaterusersdown‐gradientofthedischarge(s)havedrinkingwaterthatmeetsapplicablestateandfederalstandards.ACPsmayincludebothinterimactions(e.g.,bottledwater)intheshort‐term,permanentsolutions(suchaswell‐headtreatmentoralternativedrinkingwater

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Section 4 Central Valley Salt and Nitrate Management Strategy supplies)intheintermediateterm,andeffortstore‐attainthewaterqualityobjective(wherefeasibleandpracticable)overthelong‐term.Anyshortand/orlong‐termdrinkingwatersolutionsmustbedevelopedwithparticipationandconcurrenceofthosebenefitingfromtheproject(s).GuidelinesspecifictodevelopingACPsaresetforthinAttachmentA‐10oftheSNMP.

Topermittheuseofassimilativecapacity,theCentralValleyWaterBoardisrequiredtofindthatthedischarger,ordischargers,areimplementing“bestpracticabletreatmentorcontrolnecessarytoassurethatapollutionornuisancewillnotoccur.”Incaseswhereassimilativecapacityisbeinggrantedbasedonavailabilityofassimilativecapacityintheupperzone,theSNMPrecommendsthattheCentralValleyWaterBoardnextconsiderwhethermitigationstrategiesappliedatanyotherpointbetweenthedischargeandallaffecteddown‐gradientwaterusers(e.g.,wellheadtreatmentoralternativewatersupply,etc.)canbetterassuresafedrinkingwatertothoseusers.

Overall,itisanticipatedthatthelevelofanalysisnecessarytosupportanallocationofassimilativecapacity,andrequiredfindingsrelativetoevaluatingBPTCandcompliancewiththestate’sAntidegradationPolicy,willvarybasedontherelevantgroundwaterbeingusedtodetermineifassimilativecapacityisavailable(i.e.,shallowversusupperzones).Forexample,toevaluateifBPTCisbeingimplementedgrantinguseofassimilativecapacitybasedontheupperzone,theSNMPrecommendsthatacompleteantidegradationanalysisbepreparedbythedischarger(s),andthatsuchanalysisincludeanevaluationofalternatives,whichconsiderssocioeconomicimpactsofdifferentcontrol/treatmentmeasures,andifdifferentcontrol/treatmentmeasuresarereasonable,practicable,and/orfeasible.

InconjunctionwithevaluatingBPTC,theCentralValleyWaterBoardmustdeterminewhetherallocatingassimilativecapacitytoauthorizeadischargethatisexpectedtolowerwaterqualityis“consistentwithmaximumbenefittothepeopleofthestate.”Tomakethisfindingfornitratedischarges,theSNMPrecommendsthattheCentralValleyWaterBoardconsiderthefollowingfactors(seealsoSNMPAttachmentA‐11):

1)Economicandsocialcosts,tangibleandintangible,directandindirect,oftheproposed

dischargecomparedtothebenefitsforboththedischargerandallothersthatmaybeaffectedbythedischarge.Thisincludesanevaluationofthedischarger'scapacitytobearthecostofcompliance(e.g.,“affordability”)andanypotentialadverseimpactstothesurroundingcommunity.ThisisnotintendedtobeaformalCost‐BenefitAnalysis.

2)Environmentaleffectsofallowingorprohibitingtheproposeddischarge(especiallytheneteffectonwaterqualityintheregionandtheCentralValleyWaterBoard'slong‐termrestorationplans).Insomecases,wheretheneteffectonreceivingwaterqualityisshowntobespatiallyand/ortemporally‐limited,theCentralValleyWaterBoardmayconcludethatthedischargedoesnotresultinsignificantdegradation.

Ingeneral,theCentralValleyWaterBoardislesslikelytoallocateassimilativecapacitytodischargeswherethereisareasonable,feasible,andpracticablemeansforachievingcompliancewithtraditionalwastedischargerequirements.TheCentralValleyWaterBoardisalsounlikelytoprohibitdischargeswherenosuchmeansexistandconsidersthisoptiononlyasalastresort.

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Section 4 Central Valley Salt and Nitrate Management Strategy Notably,iftheCentralValleyWaterBoardconcludesthat,evenafterimplementingBPTC,adischargewillunreasonablyaffectpresentoranticipatedbeneficialusesofwater,orresultinwaterqualitylessthanthatprescribedintheBasinPlan,orcauseanunmitigatedpollutionornuisancetooccur,orisinconsistentwithmaximumbenefittothepeopleofthestate,thenlowerwaterqualitycannotbeauthorizedbyallocatingaportionoftheavailableassimilativecapacity.However,thedischarge(s)maystillbepermittediftheCentralValleyWaterBoarddeterminesthatitisappropriatetograntanexceptiontomeetingthewaterqualitystandardfornitrate.ThegrantingofsuchexceptionsfornitratesisdiscussedimmediatelybelowinSection4.3.2.4.

4.3.2.4 Granting an Exception to Meeting the Water Quality Objective for Nitrate TheSNMPrecommendsthatwhereexistinggroundwaterqualityalreadyexceedstheMCLfornitrate(i.e.,>10mg/L),orwheretheCentralValleyWaterBoardisunabletoallocateavailableassimilativecapacity,thattheCentralValleyWaterBoard'sforemostgoalshouldbetoencouragerapidimplementationofsafedrinkingwateralternatives.Toachievethisgoal,theCentralValleyWaterBoardneedsadditionalpermittingoptions.Specifically,theSNMPrecommendsthattheBasinPlansbeamendedtoextendandexpandtheCentralValleyWaterBoard'scurrentauthoritytoauthorizeexceptions34undercertaincircumstances.Thissectiondescribeshowsuchexceptionsauthorityshouldbeappliedwithrespecttopermittingnitratedischargestogroundwater.AmoredetaileddescriptionofthespecificbasinplanrevisionsrequiredtoenactabroaderexceptionspolicyandtherationaleforsuchchangesisprovidedinAttachmentA‐4(ExceptionsPolicy).

An“exception”allowstheCentralValleyWaterBoardtoauthorizeadischargetooccurevenwheredoingsomayviolateapplicablewaterqualitystandardsinthereceivinggroundwaterbasin.35Exceptionsaremostcommonlyemployedwhenthereisnofeasible,practicableorreasonablemeansforadischargetomeetwithwaterqualityobjectivesanditisnotfeasible,practicableorreasonabletoprohibitthedischarge.

Exceptionsareanappropriateoptionwhenstateauthoritiesdeterminethatprohibitingadischargewoulddomoreharmthangoodandallowingittocontinueisinthebestinterestsofthepeopleofthestate.Exceptionsmayalsobeanappropriatetooltoauthorizethetimerequiredtoimplementotherregulatorysolutions(e.g.,developingsite‐specificobjectivesorreevaluatingtheapplicablebeneficialuse)ortosupportaprogramofphasedimplementationandreasonableresourceallocationincludingtheplanningandpermittingactivitiesrequiredinsuchprograms.However,exceptionsarenotintendedtobeapermanentwaiverfromcomplianceobligations.Theyaresubjecttospecifiedconditionsandreviewableperiodically.

Ingrantinganexception,theCentralValleyWaterBoardmustconsiderthethreemanagementgoals,asdiscussedinSNMPSection4.1.1.Inaddition,thisSNMPrecommendstwooverarchingconditionswhenauthorizinganexceptionfornitrate:

34CentralValleyWaterBoardResolutionNo.R5‐2014‐0074(June6,2014);subsequentlyapprovedbytheSWRCBinRes.No.2015‐0010(March17,2015).

35Exceptionsfromcompliancewithwaterqualitystandardsinagroundwaterbasinissimilartotheconceptofa“variance”forsurfacewaters.Thekeydistinctionisthatexceptionsaregovernedexclusivelybystatelawandvariancesaresubjecttobothstateandfederalauthority.See,forexample,Resolution.No.R5‐2014‐0074.AlsoseeSNMPAttachmentA‐6.

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DischargersarestillexpectedtomakereasonablebesteffortsintendedtocomplywithapplicableWDRswhenthereexistsafeasibleandpracticablemeansfordoingso.

Inlieuofmeetingtheapplicablewaterqualityobjectivefornitrate,dischargerswillbe

expectedtoproposeanACPdesignedtomitigatethesignificantadverseeffect(s)oftheirpermitteddischargeasitrelatestonitrateforwhichanexceptionisgranted(seeAttachmentA‐10forrequiredelementsforanACP).Moreover,anACPfornitratewillneedtoassurethatgroundwaterusersdown‐gradientwhosegroundwaterisimpactedbythedischargehavedrinkingwaterthatmeetsapplicablestateandfederalstandards.ACPsmayincludeinterimactions(e.g.,bottledwater)intheshort‐term,permanentsolutions(suchaswell‐headtreatmentoralternativedrinkingwatersupplies)intheintermediateterm,andeffortstore‐attainthewaterqualityobjective(wherefeasibleandpracticable)overthelong‐term.

TheSNMPrecommendsthatexceptionsbereviewablefortworeasons:

Althoughthemeanstoassurecompliancemaynotcurrentlyexist,newsourcecontroland

treatmenttechnologiesmaybedevelopedinthefuture.Therefore,exceptionsneedtobeperiodicallyreassessed.

Permanentexceptionswouldbetantamounttonullifyingthedesignateduse.Therefore,wherecompliancecannotbeassured(evenoverthelong‐term),theStateWaterBoardhasstatedthattheRegionalBoardsshouldconsiderwhetherthewaterqualitystandarditselfisappropriate.36Exceptionsareintendedtocomplement,notreplace,thewaterqualitystandardsreviewprocess.

IntheBasinPlans,guidanceunderthecurrentexceptionspolicyisrestrictedtoalimitednumberofsalinityconstituents(electricalconductivity,TDS,chloride,sulfateandsodium).37AsdiscussedinSection4.2.2.3andAttachmentA‐4,thispolicyshouldberevisedinordertoprovidetheCentralValleyWaterBoardadditionalguidanceforallowingexceptionsfornitrateinWDRs.Specifically,pertherecommendationsofthisSNMP,tograntanexceptionfordischargesofnitrate,Figure4‐8summarizesthefactorsthattheSNMPtheCentralValleyWaterBoardshouldconsider.

Finally,toapproveanexceptionfornitrate,theSNMPrecommendsthattheCentralValleyWaterBoardconsiderwhethertheACPwillresultinahigherlevelofpublichealthprotection(e.g.,greaterorfasterriskreduction)thanislikelytootherwiseoccurifthedischargewereprohibitedorisakeypartofalong‐termrestorationstrategy.Inotherwords,willtheACPdoabetterjobofachievingthereal‐worldoutcomesoriginallysoughtbyrequiringstrictcompliancewithWDRstomeetwaterqualitystandards.

36StateWaterBoardOrderNo.WQ‐81‐5:IntheMatterofthePetitionoftheCityofLompocforReviewofOrderNo.80‐03(NPDESPermitNo.CA0048127),CaliforniaRegionalWaterQualityControlBoard,CentralCoastRegion.(March19,1981).

37CentralValleyWaterBoardResolutionNo.R5‐2014‐0074.


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Figure 4‐8. Factors to Consider When Authorizing an Exception for Nitrate in a WDR

Nitrate concentrations in the groundwater basin and whether they exceed or threaten to exceed the MCL.

If there is no feasible, practicable or reasonable means for the discharger to assure compliance with the

relevant WDRs governing nitrate under traditional permitting approaches, or if a proposed ACP can

further the goals of the SNMP more effectively than the traditional permitting approach.

With respect to determining if it is infeasible, impracticable or unreasonable to prohibit the discharge,

the Central Valley Water Board shall consider guidelines for making such an assessment if such

guidelines are developed in the future. The Central Valley Water Board’s obligation to follow any future

developed guidelines will depend on the process used for acceptance of the guidelines by the Central

Valley Water Board.

If authorizing the discharge is in the best interests of the people of the state.

The discharger, or group of dischargers, proposes to implement an ACP in lieu of meeting the relevant

WDRs for nitrate.

The ACP provides appropriate wellhead treatment or an alternative drinking water supply to down‐

gradient groundwater users impacted by the discharge(s) and where nitrate levels exceed or threaten to

exceed the MCL.1

The discharger continues to make reasonable best efforts, where feasible and practicable, to further

reduce nitrate concentrations in the discharge.

The discharger is participating in efforts towards implementation of the long‐term nitrate compliance

plan, as described in the permitting pathways options.

1 The discharger may propose to participate in a regional project or make one or more payments to a regional nitrate mitigation fund approved as an ACP subject to Regional Water Board review and approval.

4.3.3 Salt Management SaltmanagementunderthisSNMPwillbeguidedbytheSalinityManagementStrategy(seeAttachmentA‐3).Belowisasummaryofthekeyelementsofthisstrategy.

4.3.3.1 Overview

AsnotedinSection4.2.4.2,currentsalinitymanagementactivitiesmayonlyaddressabout15%oftheannualsaltload;accordingly,long‐termsolutions,includingdevelopmentofregionalde‐saltersandaCentralValleyregulatedbrinelineareneededtoaddresstheother85%.Theselong‐termmanagementstrategieswillrequiresignificantstateandfederalfundingtoimplement.

Inthemeantime,theCentralValleyWaterBoardmustimplementtheBasinPlansthroughtheadoptionofWDRs/ConditionalWaiversthatconsiderthebeneficialusestobeprotectedandthewaterqualityobjectivesassociatedwiththosebeneficialuses.

Becausethesolutionsforaddressingsalinityarelong‐terminnature,theCentralValleyWaterBoardneedstobeabletoconsiderinnovativesaltmanagementstrategiesforboththeshort‐termandthelong‐termthatmovetheregiontowardsaltbalanceandrestorationofimpactedareaswherereasonableandfeasible.ThisincludesneedingadditionalregulatoryflexibilitywithrespecttotheissuanceofWDRs/ConditionalWaiverswithsalinityrelatedrequirements.Somesalinity‐relatedpoliciesbeingproposedwiththisSNMPinclude:

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RevisionsoftheExceptionsPolicyforWasteDischargestoGroundwater(ExceptionsPolicy–seeSNMPAttachmentA‐4);

SalinityManagementtoProvideReasonableProtectionofAGRBeneficialUsesin

Groundwater(AGRPolicy–seeSNMPAttachmentA‐6);

RevisionsoftheSalinityVarianceProgram(SalinityVariancePolicy–seeSNMPAttachmentA‐5);

OffsetPolicy(seeSNMPAttachmentA‐7); DroughtandWaterConservationPolicy(seeSNMPAttachmentA‐8);and

GuidancetoImplementSecondaryMaximumContaminantLevels(SecondaryMCLPolicy,

seeSNMPAttachmentA‐9) TheapplicabilityofthesevariouspolicieswillvarydependingonimplementationoftheSalinityManagementStrategydescribedbelow.

4.3.3.2 Salinity Management Strategy

Overall,theSalinityManagementStrategyprovidestheCentralValleyWaterBoardwithaprocessformovingforwardwithlong‐termsalinitymanagementwhileidentifyinganinterimpermittingapproachforsalinitydischarges.Thisstrategyisintendedto:

Controltherateofdegradation(“manageddegradation”); Achievelong‐termsustainability(saltbalance),wherefeasible,practicableandreasonable;

and Protectsbeneficialusesbymeetingapplicablewaterqualityobjectivesandapplying

appropriateantidegradationconcerns. Becauseofthelong‐termnatureofsalinitymanagement,thisSalinityManagementStrategyisphasedovertime(Table4‐7).ThefirstphaseconsistsofdevelopingaPrioritizationandOptimizationStudyforsalinitymanagementfortheentiretyoftheCentralValleyRegion.TheoverallgoalofthisstudyistofurtherdefinetheconceptualdesignofSSALTS(CDMSmith2014,2016b)intoafeasibilitystudythatidentifiesappropriateregionalandsubregionalprojects,includinglocation,routingandimplementation/operationofspecificsaltmanagementprojects(seeTable4‐7).SubsequentphasesoftheSalinityManagementStrategywillemphasizeenvironmentalpermitting,engineeringdesignandacquiringfunding(PhaseII)andconstructionofsaltmitigationprojects(PhaseIII).

Figure4‐9providesanillustrationofanticipatedkeymilestonestobecompletedduringthePhaseIPrioritizationandOptimizationStudy.Whileitisanticipatedthatcompletionofthesemilestoneswilltakeapproximately10‐years,CV‐SALTSrecommendsthattheExecutiveOfficeroftheCentralValleyWaterBoardbegiventhedirectauthoritytoextendthistimeframeifcompellingreasonsoradequatejustificationisprovidedforanextension.


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OncethePrioritizationandOptimizationStudyiscompletedandtheBasinPlansareamendedbasedonrecommendationsfromtheStudy,PhaseIIoftheSalinityManagementPlanwillbeimplemented.ImplementationofPhaseII,inwholeorpart,willoccurasdirectedbythefindingsofthePrioritizationandOptimizationStudy,andafterapprovalofanynecessaryBasinPlanamendments.ThedurationofPhaseIIisanticipatedtobeapproximately10years.Aswith PhaseI,theExecutiveOfficeroftheCentralValleyWaterBoardshouldbegiventheauthoritytoextendtheanticipatedtimeframeforcompellingreasons,whichmayincludeavailabilityofadequatefundingtomoveforwardwithimplementationofPhaseII.ActualconstructionofphysicalprojectswouldoccurinPhaseIII,subjecttoavailablefunding,completionandapprovalofenvironmentalimpactstudies,andothernecessaryapprovals.

Table 4‐7. Salinity Management Strategy Phases

Strategy Phase Key Activities

Phase I

Prioritization and Optimization Study:

Evaluate the impact of all state policies that impact management of salinity in

the Central Valley region (e.g., Bay Delta Plan) to both surface and ground

waters;

Identify physical projects and proposed locations for long‐term management of

salinity (e.g., regulated brine line, salt‐sinks, regional/subregional de‐salters,

recharge areas, deep well injection, etc.);

Identify non‐physical projects that help with managing salinity;

Develop governance structures for implementation of the physical projects;

Identify funding sources necessary for implementation of large‐scale capital

physical projects (state and federal capital expenditures);

Identify the various environmental permits (and time‐line for obtaining the

permits) needed to implement the preferred physical projects;

Identify and propose any necessary Basin Plan changes that may be necessary

to implement the next Phase or Phases of the Salinity Management Strategy

(e.g., Offset Policy in surface waters);

Develop the conceptual design for applicable projects; and,

Other related activities.

Implement Interim Salinity Permitting Approach

Phase II

Environmental Permitting

Engineering Design

Obtain Funding

Revises Interim Salinity Permitting Approach (as needed)

Phase III

Salinity mitigation project construction including Central Valley regulated brine line

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Figure 4‐9. Milestones for Implementation of Phase I of the Salinity Management Strategy

Category

Year of Implementation

1 2 3 4 5 6 7 8 9 10

Stakeholder

Coordination

Stakeholder Coordination Meetings (as needed frequency)

SGMA GSA Coordination Meetings (as needed frequency)

Strategic Planning

Regulatory and Policy Evaluations

Phase II Planning

Governance

Governance Plan – Formation and Structure

Implementation and Refinement of Governance Plan

Funding

Funding Plan and Financing Strategy

Implementation of the Funding Plan and Financing Strategy

Prioritization &

Salinity Management

Analyses

Prioritization/Salt Management Analyses to Support

Identification of Salt Management Projects

Interim

Report

Conceptual Design of

Salt Management

Project

Concept Design for Subregional Salt Management Projects

and Regional CVBL Project

Special Studies

Groundwater Quality Trace

Constituent Stud

Emerging

Tech Update

No. 1

Emerging

Tech Update

No. 2

Emerging

Tech Update

No. 3

Recycled Water Imports

Study

Stormwater Recharge Master

Plan Study


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4.3.3.3 Interim Salinity Permitting Approach

WhilethePrioritizationandOptimizationStudyisbeingimplemented,thisSNMPrecommendsthattheBasinPlansbeamendedtoincludeanInterimSalinityPermittingApproachfordischargesofsalinity.ThisapproachwouldallowtheCentralValleyWaterBoardtomanagedegradationwhilethelong‐termsalinitymanagementeffortsarebeingimplemented.Becausethisapproachisintendedtobeinteriminnature,thisapproachwouldlikelyincludeasunsetprovisionintheBasinPlans,whichcouldbereneweddependingontheeffortsassociatedwithimplementingthevariousapplicablephasesoftheSalinityManagementStrategy.Attheoutset,CV‐SALTSrecommendsthattheInterimSalinityPermittingApproachbesetinplacefor15yearstoallowforimplementationofPhaseIoftheSalinityManagementStrategy.AttheendofPhaseI,theInterimSalinityPermittingApproachmayneedtobeextendedtoallowforimplementationofPhaseII,ortoadjusttheapproachasdeemedappropriatetoimplementPhaseII.AnysuchchangemayrequireaBasinPlanamendment.

Basis for Interim Salinity Permitting Approach

Theproposedinterimpermittingapproachforsalinityisbasedonthefollowingfindingsandgoverningprinciples: Thisapproachappliestopermittingsalinitydischargestosurfaceandgroundwaterinthe

definedinterimperiod. Theproposedapproachforpermittingsalinitydischargestosurfaceandgroundwatermust

beimplementedinamannerconsistentwithstateandfederalAntidegradationPolicies(i.e.,StateWaterBoardResolutionNo.68‐16andfederal40CFR131.12,respectively),asapplicable.

NoprovenmeansexistatpresentthatwillallowongoinghumanactivityintheCentralValleyRegionandmaintainsalinitylevelsthroughouteverygroundwaterbasin.38Waterconservationandincreasedrecycledwaterusealsoincreasesalinitylevelsingroundwater.Therefore,theInterimSalinityPermittingApproachfocusesonmanagingdegradationwhilethelong‐termcomponentsoftheSalinityManagementStrategyarebeingimplemented.

Itisreasonabletoemployalong‐terminterimpermittingapproach.Forexample,thesaltloadcurrentlyexistinginthevadosezoneistypicallyunknown,butthisloadcanimpactthequalityoftheunderlyinggroundwaterovermanyyears.Inaddition,thetimerequiredforrechargewatertotransitthevadosezoneandreturntouseasgroundwateratanirrigationsupplywellcanbesignificant.

Becauseofthelong‐termnatureandanticipatedhighcostsforimplementationoftheSalinityManagementStrategy,itisreasonabletoexpectthatdischargerswillnotbeabletoimplementsuchstrategiesindividually,butwillneedtoparticipateinalargerregion‐widecollectiveeffort.ThelargercollectiveeffortwouldbeginwithimplementationofthePrioritizationandOptimizationStudy(PhaseI),followedbyPhasesIIandIII.Duetothe

38TLBBasinPlan,Pg.III‐8.

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anticipatedcostsoftheseefforts,itisappropriatethatdischargesnotbesubjecttoextensiveand/orexpensivesalinitypermitrequirementsduringthisinterimperiod.Inparticular,individualdischargeeffortswouldhavelittleimpactonCentralValleysalinitymanagementasawhole,andassuchtheyarenotreasonable,feasibleorpracticable.

Itisreasonabletoexpectthatpermitrequirements(e.g.,WDRs/ConditionalWaivers,NPDESPermits)withrespecttoimplementingthelong‐termSalinityManagementStrategytoallowtimetoaddressdrinkingwaterissuesfornitratesfirst.TheSNMPidentifiesnitratedrinkingwaterissuesasitsfirstnear‐termpriority(seeSection4.1.1).Salinityisalsoapriority,butduetothecomplexitiesassociatedwithsalinity,itwillneedtobeaddressedoverthelong‐term.

Toallowforthephasedapproach,andtheinterimpermittingapproachdescribedherein,themanageddegradationobjectivesandspecifiedsalinitylimitationsintheTLBBasinPlanneedtobedeletedfromtheBasinPlan.

TheCentralValleyWaterBoardretainsauthoritytoidentifyhighprioritysalinedischargesand/orareaswheremorestringentcontrolprogramsmustbeimplemented.

Permitting Approach

Giventhediscussionabove,CV‐SALTSrecommendsaninterimpermittingapproachforsalinity‐relateddischargestosurfaceandgroundwater.ToimplementthisapproachinWDRs/ConditionalWaivers,theCentralValleyWaterBoardwillneedtorenew/reviseexistingWDRs/ConditionalWaiversandNPDESPermits.Further,duringthisinterimperiod,therewillbenewdischargers,orexistingdischargersseekingfacilitymodifications,thatwillhavesalinitydischarges.TheSNMPrecommendsaprioritizationapproachforaddressingnitratedrinkingwaterissuesbasedontheseverityofwaterqualitycontaminationandimmediateimpacttousers(seeSection4.2.3).ItisnottheintentoftheSalinityManagementStrategytouselimitedavailableresourcestoreviseindividualWDRs/ConditionalWaiversandNPDESPermitsforsalinity,especiallywheretherearesignificantnitratewaterqualityissues.However,thereisaneedtoensurethateffortsaremovingforwardwithrespecttothePhaseIPrioritizationandOptimizationStudy.

Tobalancethesetwoneeds,thisSNMPrecommendsthattheCentralValleyWaterBoard,incooperationwithstakeholders,implementaprocesswherebyaseriesofresolutions/ordersthatamendapplicableWDRs/ConditionalWaiversareconsideredforadoptionbytheCentralValleyWaterBoardtoimplementtheInterimPermittingApproach(seeSection4.3.3.5below).ThisapproachwouldprovidefordischargercompliancewithsalinitywaterqualityobjectivesduringPhaseIoftheimplementationoftheSalinityManagementStrategyaslongasthedischargerisincompliancewithInterimPermitProvisionsapplicabletotheirdischarge(asdescribedbelow),ratherthanthroughstringentwaterreceivinglimitsand/oreffluentlimits.

Interim Permit Provisions

InterimPermitProvisionswouldrequiredischargerstocontinuecurrentreasonable,feasibleandpracticableeffortstocontrollevelsofsalinityintheirdischargeswhileparticipatingineffortstoconductthePhaseIPrioritizationandOptimizationStudy.InterimPermitProvisionsmayincludethefollowingrequirementsasapplicableandappropriate:

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Implementsalinitymanagementpracticesand/orsourcecontrolefforts; Implementpollutionpreventionplans,watershedplans,and/orsaltreductionplans;

Monitorforsalinityinsurfaceandgroundwateraspartofexistingmonitoringprograms,or

throughregionalmonitoringprogramsasappropriate,whichshouldbecoordinatedwiththesurveillanceandmonitoringprogramestablishedtosupportimplementationofadoptedBasinPlanamendmentstofacilitateSNMPimplementation(seeSNMPSection5);39

Maintaincurrentdischargelevelsofsalinitytotheextentfeasible,reasonable,andpracticable,whileaccountingforconservation,salinitylevelsinthewatersupplysource,andsomeappropriateincrementofgrowth;and/or

Complywithinterimpermitlimits,totheextentthattheCentralValleyWaterBoardfindsitappropriateandnecessarytoadoptsuchlimits.

Alldischargerswouldberequired,andallinterimpermitswouldneedtoinclude,thefollowingrequirement: ParticipateineffortsrelatedtoconductingthePhaseIPrioritizationandOptimization

Study,andsubsequentPhasesIIandIIIasapplicable.Thelevelofparticipationwouldvarybasedonsalinityinthedischargeaswellaslocalconditionsandtheneededlevelofparticipationestablishedbytheleadentity(i.e.,CVSC)thatisoverseeingthePrioritizationandOptimizationStudy.

Itisrecommendedthattheresolutions/ordersestablishthetime‐frameforapplicationoftheInterimPermittingApproachandassociatedprovisions,whichcouldnotexceed15yearsinlength.ForNPDESdischargers,whicharesubjecttofederalregulatoryrequirements,CV‐SALTSrecommendsthatasNPDESpermitsarerenewedontheirnormalfive‐yearcycle,thattheCentralValleyWaterBoardconsiderapprovalofasalinityvariancepertheSalinityVariancePolicy(seeAttachmentA‐6),whichwouldincludearequirementtoparticipateinthePrioritizationandOptimizationStudyinordertoreceivethevariancefrommeetingapplicablesurfacewaterqualityobjectivesforsalinity.Or,inthealternative,theCentralValleyWaterBoardcouldconsideranNPDESwatershed‐basedpermitforsalinityasitdeemsappropriate,whichtoowouldrequirethosecoveredbythewatershed‐basedpermitforsalinitytoparticipateinthePrioritizationandOptimizationStudyefforts.

4.3.3.4 Opting Out of Participation in the Phase I Prioritization and Optimization Study ItisanticipatedthattheCentralValleyWaterBoardwillencourageandthatmostdischargerswillchoosetoparticipateineffortsrelatedtoconductingthePhaseIPrioritizationandOptimizationStudy.However,theCentralValleyWaterBoarddoesnothavetheauthoritytoforcedischargersintotheInterimPermittingApproach,andtoparticipateinthePrioritizationandOptimization

39TheCentralValleyWaterBoardwouldretainitsauthoritytoidentifyhighprioritysalinedischargeswheremorestringentcontrolprogramsmustbeimplemented.

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Section 4 Central Valley Salt and Nitrate Management Strategy Study.Further,somedischargershavealreadymadesignificantchangestotheiroperationinordertomeetrestrictivesalinitylimitationsandmaydecidethattheInterimPermittingApproachdoesnotprovidethemwithanappropriateincentivetoparticipate.Accordingly,theSalinityManagementStrategyincludesanoptionfordischargerstooptoutofparticipatingineffortsrelatedtothePrioritizationandOptimizationStudy.Forthosedischargersthatchoosetooptout,CV‐SALTSrecommendsthattheCentralValleyWaterBoardpermitsuchdischargersbyimplementingthefollowingprinciples:

1.InterpretingNarrativeWaterQualityObjectives–Whenitinterpretsnarrativewaterqualityobjectivesfordischargersoptingout,theCentralValleyWaterBoardshouldselectapplicablesalinitywaterqualityobjectivesinaconservativemanner.FortheAGRbeneficialuse,theCentralValleyWaterBoardshouldapplyaconservativelyprotectiveagriculturalgoal(e.g.,700µS/cmforelectricalconductivity).However,indeterminingtheagriculturalgoalthatshouldbeusedtointerpretthenarrativeobjective,theCentralValleyWaterBoardshouldconsiderwhetherasitespecificagriculturalgoalhasbeendevelopedand/orpreviouslyadoptedforthedischargerinquestion.Ifasitespecificgoalhasbeendevelopedand/orpreviouslyadopted,CV‐SALTSrecommendsthattheCentralValleyWaterBoardcontinuetoapplythatvalueifstillappropriate.FortheMUNbeneficialuse,theCentralValleyWaterBoardshouldinterpretwaterqualityobjectivesinamannerconsistentwiththeSNMPguidanceforImplementationofSecondaryMaximumContaminantLevels(seeAttachmentA‐9).40

2.AllocationofAssimilativeCapacity–Fordischargersoptingout,nonewallocationofassimilativecapacity,orexpansionofanallocationofassimilativecapacityshouldbegrantedbytheCentralValleyWaterBoard.However,ifadischargerhaspreviouslyreceivedanallocationofassimilativecapacity,andsuchallocationwasgrantedwiththesupportofanantidegradationstudy/analysis,thentheCentralValleyWaterBoardshouldcontinuetoallocatethepreviouslyapprovedassimilativecapacity,ifstillappropriate.Forgroundwaterdischargerswishingtooptout,thiswouldessentiallymeanthattheywouldneedtoshowthattheydonotcauseorcontributetoexceedancesofgroundwaterlimitationsforsalinityconstituentsinshallowgroundwaterunlesstheyhadpreviouslybeenpermittedtheuseofassimilativecapacityinthegroundwater,andsuchpreviouslyauthorizeduseofassimilativecapacitywasreauthorizedbytheCentralValleyWaterBoard.

3.IssuanceofTimeSchedules‐CV‐SALTSrecommendsthattheCentralValleyWaterBoarduseitsdiscretiontoissuetimeschedulesformeetingsalinitylimitationsforthoseoptingoutsparingly,andforminimaltimeperiods.Inotherwords,adischargeroptingoutshouldgenerallybeallowednomorethanfiveyearsformeetingarestrictivesalinitylimitation.However,theCentralValleyWaterBoardmaintainsthediscretiontodetermineifatimescheduleisappropriate,andthelength,fordischargersseekingtooptout.

40IftherearesitespecificwaterqualityobjectivesforsalinityconstituentsintheapplicableBasinPlan,suchobjectiveswouldapply.

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4.NPDESPermittees–ForsurfacewaterdischargerssubjecttoanNPDESpermitthatwishtooptout,theCentralValleyWaterBoardneedstodeterminereasonablepotentialinamannerthatisconsistentwith40CFR§122.44(d),andshoulddetermineifacompliancescheduleisappropriatebasedoncurrentapplicablelawsandpolicies,includingconsiderationofmeetingtheSNMPgoals.Wheninterpretinganarrativewaterqualityobjectivetoconductareasonablepotentialanalysis,theCentralValleyWaterBoardmustemployPrinciple1above.Further,NPDESpermitteesshouldnotbeallowedtooptoutiftheyareseekinganewallocationofassimilativecapacity(i.e.,mixingzone/dilutioncredit)inasurfacewaterformeetingthesalinitylimitation.However,theCentralValleyWaterBoardshouldconsidermaintaininganypreviouslyapprovedmixingzone/dilutioncredits.SalinityvarianceswouldnotbeanavailableoptionforthoseseekingtooptoutofthePrioritizationandOptimizationStudy.Insummary,NPDESdischargerswishingtooptoutwouldessentiallyneedtoshowthat:

Thedischargedoesnothavereasonablepotentialtoexceedtheapplicablecriteria;

Thedischargeisabletocomplywithawaterquality‐basedeffluentlimit,ifthereisreasonablepotential;or

Thedischargewillbeabletocomplywithawaterquality‐basedeffluentlimitation

subjecttothetermsofacompliancescheduleapprovedbytheCentralValleyWaterBoard.

4.3.3.5 Process for Development and Adoption of Resolutions/Orders to Implement Interim Permitting Approach Topreparetheappropriateresolutions/ordersthatamendthesalinityprovisionsinexistingpermitsandthatestablishsuchprovisionsforfuturepermits,CV‐SALTSrecommendsthattheCentralValleyWaterBoardandrelevantstakeholdersbegintheprocessfordevelopingsuchresolutions/ordersassoonaspossible.ItisrecommendedthatsuchresolutionsbepreparedandreadyforCentralValleyWaterBoardconsiderationwithinone(1)yearoftheBasinPlanamendmentsadoptedtofacilitateimplementationofthisSNMPbecomingeffective.Inthemeantime,whilesuchresolutionsarebeingdeveloped,CV‐SALTSrecommendsthattheCentralValleyWaterBoardpermitsalinitydischargesinareasonablemannerthatlooksforwardtowardsimplementingtheSalinityManagementStrategyassetforthintheSNMP.

4.3.3.6 Potential Future Permitting Approach

AtthecloseofPhaseI,orpotentiallyattheendofPhaseII,theCentralValleyWaterBoardmaydeterminethatitisnecessarytorevisetheInterimSalinityPermittingApproach.ThismayincludetheneedtoprovidefurtherguidancewithrespecttointerpretationandapplicationofsalinitystandardsforprotectionoftheAGRandMUNbeneficialuses.ThroughtheCV‐SALTSprocess,policydocumentshavebeenpreparedthataddressapplicationofsalinitystandardsforprotectionofAGR(AttachmentA‐5),aswellasapplicationofthesecondaryMCLsforsalinity(AttachmentA‐9).ThedocumentsarepartofthisSNMP,andmayresultinBasinPlanamendmentsin2017asdeterminedappropriate.However,fortheAGRPolicyinparticular(AttachmentA‐5),itmaybemoreappropriatetonotamendtheBasinPlansin2017to

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Section 4 Central Valley Salt and Nitrate Management Strategy incorporatethosepolicyrecommendations,butratherwaituntilaftercompletionofPhaseIoftheSalinityManagementStrategy.

4.3.4 Development of Alternative Data Section3.3ofthisSNMPprovidesasummaryoftheambientwaterqualityconditionsandavailableassimilativecapacityforeachofthegroundwaterbasinsandsubbasinsintheCentralValley.Dischargersmayusethesedataasthebasisfordeterminingiftheirsaltornitratedischargewillcausedegradationofthereceivingwater.Becausethesevaluesrepresentvolume‐weightedaveragesoftheavailablewaterqualitydataforthearea(horizontallyandvertically),potentialvariabilityfromonepartofagroundwaterbasin/subbasiniscapturedbythevaluesassignedtothegroundwaterbasins/subbasins.However,asillustratedinSection3,thisvariabilitycanbesignificant.

WhencharacterizingwaterqualityforthepurposesofcomplyingwiththeNOIrequirementsforcompliancewiththenitratepermittingrequirementsofthisSNMP(seeSection4.3.2.2),adischargermayrelyonthedatacontainedorreferencedhereinorprovidealternativedatathatisdeemedmorerepresentativeoftheareaundertheinfluenceofthedischarge.Fordischargesthatoccuroveralargearea(e.g.,agriculturaldischarges),thedefaultvaluesinthisSNMPmorelikelycharacterizetypicalwaterqualityconditions,althoughadischargemayprovideadditionalinformationandrefinethemodelsusedtocharacterizeexistingwaterqualityconditions.Incontrast,dischargersthatimpactarelativelysmallareamyfinditisappropriatetoevaluatetheexistingwaterqualityconditionsandtrendswithintheirareaofinfluence.

Ifadischargeroptstoprovideanalternativedatasetforthepurposesofassessingexistingwaterqualityconditionsandwaterqualitytrendsandprovidethebasisforanalternativeevaluationofassimilativecapacity,thedischargershallprovidethecompletesetofdatausedtodevelopalternativecompliancevaluesfortheareaundertheinfluenceofthedischarge.Ataminimum,thedatasetshouldinclude:

Welllocationsandwellconstructiondata,totheextentavailable,

Waterqualitydataforeachwellfortheshallowzone,upperzone,lowerzone,andthe

productionzone,totheextentdataareavailable. Evaluationofthequalityandrepresentativenessofthedatausedinthedataanalysis.

Methodstocalculateexistingambientwaterqualityandassimilativecapacityand

determinetrends. Ifthedataanalysisisbasedonwaterqualitymodeling,thedischargershallprovidesufficientinformationtoallowBoardstafftoevaluatethemodel.

attachment 1. section 4 central valley salt nitrate ... · 4‐4 section 4 central valley salt and...

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