e @ Water Quality Control Board California Regional

e
Alan C, Lloyd' Ph.D.
AgehcySecretary
CaliforniaRegionalWater Quality Control Board
Central Valley Region
Robert Schneider, Chair
Sacramento Main Olfice
11020SunCenterDrive#200.RanchoCordova,Califomia95670-61l4
(916)464-3291. Fax(916)4644645
gov/centralvalley
hllp;//*r'w. r,!aterboards.ca.
TO:
Antonia Vorster
Engineer
Supervising
FROM:
DATE:
24 February2000
SIGNATI]RE:
@
Arnold
Schrvarzenegg€r
Cottemor
Kenneth Landau
AssistantExecutive Offi cer
SIJBJECT: EXPLANATION OF INTERIM OPERATING LIMITS FOR HILMAR CHEESE
PROCESSINGFACILITY AS CONTAINED IN PARAGRAPH 5(d) OF THE
FEBRUARY 10,2006 TENTATIVE REVISED SETTLEMENT AGREEMENT
BETWEEN THE PROSECUTION STAFF OF THE CENTRAL VALLEY RTGIONAL
WATER QUALITY CONTROL BOARD, CENTRAL VALLEY REGION, AND THE
HILMAR CHEESE COMPANY, INC. AND HILMAR WHEY PROTEIN, INC,
As leaderofthe Board's ProsecutionTeam in this matter,I am sendingyou, as a representativeofthe
Board's Adjudicatory Team,this memorandumthat containsan explanationof how the Prosecution
Team views the Interim OperatingLimits in the tentativerevisedSettlementAgreement. I requestthat
this memorandumbe included in the AgendaPackagefor this item at the March 2006 RegionalBoard
meeting,or be otherwisetransmittedto the Board membersand public for their review and
consideration.
This documentis not part ofthe SettlementAgreement,but provides an explanationof the purposeand
derivation ofthe Interim OperatingLimits containedin Paragraph5(d) of the TentativeRevised
SettlementAgreement(Agreement).
The RegionalBoard tlpically imposesinterim effluent limits, interim dischargeconditions,and other
constraintsas appropriatein wastedischargerequirementsand enforcementorders(e.g.,ceaseand desist
orders)when an existing dischargecannotachievecompliancewith prescribeddischargespecifications.
The purposeofany interim limit is to establishthe thresholdthat defineswhether a dischargeris "doing
the best it can" until full compliancecan be achieved. Interim limits are developedby examining recent
operationalhistory ofa facility and deriving conditionsthat the dischargercan reasonablymeet with the
existing treatmentsystemsand operationsat the facility. Interim limits generallyare set at a level that
approximatesthe current dischargeconditionsand doesnot allow for expansionsbeyondthe current
dischargeat a facility. Interim limits take into accountthe normal variability of influent wastewater
characteristics,treatmentsystemoperation,and samplingand laboratoryanalyses.Interim limits also
acknowledgethat existing treatmentsystemsmay not be as reliable as either the RegionalBoard or
dischargerwould like, and so must accountfor somedegreeof systemfailure or operationaldifficulties.
Prescribingnumeric effluent limits is in part an analysisofexisting effluent data,but professional
judgment is also applied in settingthe final limits. Interim limits remain in effect for a prescribedperiod
of time until an enforceablecompliancetime schedulerequirescompliancewith final limits. It has been
Caldornia Environmental Protection Agency
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AntoniaVorster
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24February2006
this and other regional boards' practiceto not take enforcementaction for violations of final limits (such
as those in WasteDischargeRequirements(WDRs) OrderNo. 97-206 in this case)as long as a
dischargeris in compliancewith interim limits. This Agreementwould formalize that practiceby
making the commitmentnot to take enforcementexplicit while Hilmar is in compliancewith interim
limits.
Existing treatmentfacilities of Hilmar CheeseCompany,lnc. and Hilmar Whey Protein,Inc. (Hilmar
Cheese)are not capableof treating all wastewaterto comply with all the dischargeconditions contained
in WDRs OrderNo. 97-206 (violations of which are allegedin the Administrative Civil Liability
Complaint (Complaint No. R5-2005-0501)). The lnterim OperatingLimits in the Agreementare
intendedto requireHilmar Cheeseto operateits existing cheeseproductionfacilities and wastewater
treatmentsystemas effectively as is feasibleto precludean increasein salinity impactsto groundwater
during the Interim OperatingPeriod specifiedin the Agreement. Clarifuing languagehasbeen added
that effectively would precludeflow or salt greaterthan the limits in the Agreement. If Hilmar Cheese
violates the Interim OperatingLimits, the RegionalBoard would be free (subjectto statutoryexceptions)
to seekcivil liability for violations of WDRs OrderNo. 97-206 occuning during the period of
noncompliance.
The following is a brief descriptionof the Hilmar CheesewastewatertreaEnentsystemand the discharge
conditionsthat would be allowed by the Agreementdwing the Interim OperatingPeriod.
Statedsimply, salt is removedby Hilmar Cheesethrough a processcalled reverseosmosis(RO) in which
water containingsalt is forced under high pressuretluough thin membranes.The membraneshave small
holes that allow water, but not salt, to passthroughthe membrane.The water that has passedthrough the
membranes(called RO Permeate)is relatively low in salt and is appliedto land for crop irrigation. The
remaining water that did not passthrough membranes(called RO Concentrate)containshigh
concentrationsof salt. The RO Concentrateis currently further concentratedby evaporationand is then
trucked offsite for disposalinto SanFranciscoBay though the East Bay Municipal District Wastewater
TreatmentPlant in Oakland.
Hilmar Cheesedisposesof wastewateron two setsof land. The "Primary Fields" are fields owned and
operatedby Hilmar Cheeseor ownersof Hilmar Cheese.The "SecondaryFields" are fields owned by
otherswho have agteedto receiveRO Permeatefrom Hilmar Cheesefor irrigation purposes.
The WDRs Order No. 97-206 requirethat wastewaterdischargedto land not contain salt concentrations
(as measuredby electricalconductivity at 25'C, or EC) that exceed900 pmhos/cm. The treatment
systemcurrently in useby Hilmar Cheesecannottreat all wastewaterto meet the 900 pmhos/cmsalt
limil. Hilmar Cheesehashistorically limited dischargeof wastewaterthat exceeds900 pmhos/cmto the
Primary Fields and directedwastewaterthat meets900 pmhos/cmto the SecondaryFields. The
Agreementwould requirethat wastewaterdischargedto the SecondaryFields continueto meet the 900
pmhos/cm limit and that the wastewaterapplied to the Primary Fields be no greaterthan 3700
pmhos/cm.
The numeric Interim Operating Limits (seeAgteement, paragraph 5(d) and corresponding discharge
specifrcationsin WDRs Order No. 97 -206 aresummarizedin the following table.
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AntoniaVorster
24 February2006
InterimOperating
Limit
OrderNo. 97-206
Parameter
MaximumTotalNon-RODischargeTo
PrimaryFields
Partof 0.75mgd
total dischargelimit
I .2 mgd'
MaximumEC' To PrimaryFields
900pmhosicm
3700pmhos/cm
Discharge
MinimumRO Permeate
Not Applicable
0.6mgd
MaximumEC of RO Permeate
900 pmhos/cm
900 pmhos/cm
MaximumTotalDischargeTo Land
0.75mgd
1.9mgd
2
Million gallonsper day
Electricalconductivityat 25"C
appliedto the PrimaryFields
TheInterimOperatingLimit maximumof 3700pmhos/cmfor wastewater
discharge.FigureI is a graphof the salinity
is baseduponrecentoperatinghistoryof Hilmar Cheese's
to the PrimaryFieldsoverthepastyear. Thehorizontalline on the gaph
of wastewater
discharged
pmhos/cmInterimOperatingLimit. As canbe seenfrom Figure1, the
proposed
3700
showsthe
to the
discharge
3700pmhosicmInterimOperatingLimit is lowerthanthe salinityof Hilmar Cheese's
prevent
to
operate
system
to
will
have
the
treatment
so
Hilmar
Cheese
for
some
months,
PrimaryFields
This InterimOperatingLimit wouldprevent
a recurrence
of thehighesthistoricsalinityconcentrations.
Primary
Fieldsthatis saltierthanthewastewater
wastewater
to
the
Hilmar Cheesefrom discharging
discharsed
in recentmonths.
3,900
3,700
3,500
3,300
-=
U
3,100
2,900
2,700
2,500
r
T
i
t
r
c
>-)
V1
ta)
Y
i
4
d
o
tn
Y
h
i
:
:
.
+
tar
T
h
Y
Y
(
!
3
tr)
r
-
i
t.r
Y
Y
=
:
o
-
ra)
Y
V)
J
a
X
rr)
L\
Figure l. Electrical Conductivity of WastewaterApplied to Primary Fields in 2005.
AntoniaVorster
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24 February2006
To assurethatHilmar Cheesecontinuesto operatethetreatmentsystemto removesaltfrom the
prior to landdisposal,anInterimOperatingLimit wouldrequirethat a MINIMUM of 0 6
wastewater
be producedeachday. Hilmar Cheesecan,at times,produce
million gallonsper dayof RO Permeate
difficultiesprevent
moretreatedwaterthanrequiredby this lnterimOperatingLimit, but operational
productionof morethan0.7mgd ofRO Permeate.
consistent
thevolumes
OtherInterim OperutingLimitswouldpreventHilmar Cheesefrom continuingto increase
from the plant. Figures2 and3 showtheproposedInterimOperatingI-imitsfor
of waterdischarged
flows reportedby Hilmar Cheese.TheInterim
flow ashorizontallines,andtherecentwastewater
are:
OperatingLimits for flow
.
Themaximumvolumeof waterNOT TREATEDBY REVERSEOSMOSISto removesalt
(Non-RODischarge)
that canbe appliedto the PrimaryFields(1.2 million gallons
concentrations
perday). TheInterimOperatingLimit for Non-RODischargewouldrestrictthevolumeof this
that canbe appliedto thePrimaryFields'
saltierwastewater
Lands
. Thetotal maximumvolumeof wastewater
thatcanbe appliedto the PrimaryandSecondary
(1.9million gallonsperday). This InterimOperatingLimit for TotalMaximumDischargeto Land
flow from theplant,whichwouldpreventHilmar
in totalwastewater
wouldrestrictfurtherincreases
capacityduringthetermofthis Agreement.'
Cheesefrom expandingits processing
'1..4
t.J
Inte rim Operating Limit
1 1
l l
o,
-
0.8
0.7
0.6
q + q q q q E - s , q q H q
E E S T g E E f l5 EE A
Figure 2. Flow to Primary Fields in 2005.
I
ln addition, the Agreementprovidesthat ifthe United StatesEnvironmentalProtectionAgency issuesan injection conffol
permit for deepwell injection, followed by an "Authorization to Inject" letter, Hilmar would reduceits allowed Total
Maximum Dischargeto Land during the Interim OperatingPeriod by an amountequal to the amountit is injecting into
the well(s).
Antonia Vorster
24 Fehruary2006
2.0
1.8
Interin OperatingLimit
l.o
1.4
t 7
b,
9 l o
' "-
a
0.8
0.6
WDR OrderNo,9T-206 Flow Limit = 0.75 msd
0.2
0.0
Figure 3. Total dischargeflow to land in 2005.'
' TotalFlow duringAugustandSeptember
2005includesdischarges
of SBRdecantto ponds.Thetotal flow for September
wascalculated
by summingtheflowsfor eachwastewater
source(PrimaryFields,SBRdecantto ponds,RO permeate)
for eachwastewatet
source.
dividedby thenumberof daysin themonth,not thenumberofdaysdischarged