DWQ-2024-007601

RE0608 GEM ENGINEERING, INC. Page 31
SECTION 7: LAGOON AND CONTAINMENT BASIN CONSTRUCTION

7.1 Containment Basins Construction
Construction of the Barns and Containment Basins shall be done in accordance with design
drawings and specifications. Earthwork and liner construction shall be tested and inspected by
qualified independent geotechnical and/or engineering firms. At the completion of construction,
and prior to operation of the facility, an independent performance certification document will be
completed by a qualified professional engineer licensed in the State of Utah containing test
information and certification that basin and liner construction meets requirements of the project
design documents and the requirements contained within this report.

7.1.1 General Earthwork Construction
Earthwork and dike construction for excavation of digesters and equalization basins shall
be done as follows:
A. The area scheduled for construction of basins and building pads shall be
cleared and grubbed to remove topsoil and surface vegetation from the
digester/basin areas.
B. Soil shall be excavated from the basin area and be used to construct building
pads or dikes.
C. Basin dikes shall be constructed in 6-inch compacted lifts to obtain proper
compaction. For building pad and digester dike construction, the soil shall be
moistened and compacted to 90% of maximum dry density, as defined by
AASHTO T-99. Moisture will be added to the soil during compaction to
target 2% above the optimum moisture.
D. The dikes will be constructed of relatively impermeable compacted native
material.
E. A qualified inspector will perform the moisture content and dry density testing
per every two feet of lift at random locations once every 400 feet along the
Containment Basin dikes.

GEM ENGINEERING, INC.
7.2 Flexible Membrane Liner
Specifications for manufacture, delivery, subgrade preparation, installation, and testing for FML
liner installation are included in Attachment E. The QA/QC plan is also included in this
attachment. The specifications were adapted from requirements set forth in previous projects and
permit applications. Moreover, an industry standard known as the GRI standard GM13 which
covers smooth and textured geosynthetics has been developed with the intent of forming an
industry standard for manufacture and testing of geosynthetic liner material. This standard was
developed by the Geosynthetic Research Institute at Drexel University, Philadelphia, PA. As
stated in the specifications, the requirements of latest revision of the GRI standard will be
applicable.

If the basins are to remain empty for an extended period of time they shall be properly ballasted
using ultraviolet ray resistant sand bags with nylon ties. The minimum specification for
ballasting liner is 30-lb. sand bags spaced 5-feet apart along the entire toe of dike in containment
basins. Sand-filled HDPE tube or pipe may also be used as long as an equivalent amount of
ballasting per lineal foot (6 lbs./ln.-ft.) is maintained.

On occasion, repairs may have to be made to liners if damage occurs out of the norm, or
modifications need to be made. All repairs made to liner seams, or incident holes found in the
liner shall be vacuum/bubble tested, documented and sent to the State DEQ for informational
purposes and approval of the repairs. Unless significant modifications to the liner are made, such
repairs shall be made without any requirements for approval from the State DEQ.

7.2.1 Flexible Membrane Liner Installation
The Containment Basins at the finishing farms will be lined with a Flexible Membrane
Liner (FML) constructed of a High Density Polyethylene (HPDE). The subgrade will
conform to the FML specifications of the Manufacture and the previously stated most
resent GRI standards. The installation of the FML will also comply with the Quality
Assurance/Quality Control (QA/QC) found in Attachment E. In Addition to the FML
specifications and QA/QC, detailed drawings of typical liner anchoring methods, pipe
penetrations, air vents and water level markings of liners are found in attachment E. The

GEM ENGINEERING, INC.
following procedures will be used for installation of liners for the Containment Basins at
the farm sites.

The Subgrade will be constructed according to the specifications as detailed below:

1. The subgrade material will come from either on-site material or approved
stockpiles.
2. The earthwork for the anaerobic Containment Basins will be free of any
foreign material such as stones greater than 3/8 inch in diameter,
vegetation, brush, roots or similar material which could damage the FML.
3. The subgrade material shall be classified as either CH, CL, CL-ML, ML,
SM, SC, SW or SP by the USCS Classification System.
4. A Moisture density curve will be developed for the subgrade material.
5. The minimum compacted thickness of the subgrade layer shall be 8
inches.
6. The subgrade will be compacted and graded to meet the FML contractor’s
specifications so as to avoid any ruts, irregularities or soft areas. The
subgrade will be thoroughly compacted to provide support for the FML.
7. The subgrade will be compacted to a minimum of 90% maximum dry
density as defined by AASHTO T-99. For proper compaction, moisture
will be added to the soil during compaction to target 2% above the
optimum moisture.
8. Installed density shall be confirmed by field test methods at a frequency of
one test per 100'x100’ grid square at the surface of the subgrade.

A 60-mil HDPE will be installed over the compacted subgrade. The HDPE material will
meet the specifications indicated in the most resent GRI standard and in the QA/QC
references in Attachment E. The drawings in Attachment E show typical liner anchoring
methods and pipe penetrations of the liner material.

GEM ENGINEERING, INC.
The HDPE liner will be installed according to the following procedure:

1. The earthwork for the anaerobic Containment Basins will be constructed
so the subgrade will be free of any foreign material such as stones greater
than 3/8 inch in diameter, vegetation, brush, roots or other similar
materials which could damage the FML.
2. The earthwork will be compacted and graded to meet the FML
contractor’s specifications so as to avoid any ruts, irregularities or soft
areas. The subgrade will be thoroughly compacted to provide support for
the FML.
3. An anchor trench will be constructed along the crest of the berms for the
purpose of securing the FML.
4. The FML will be assembled, seamed, tested and installed by the methods
specified by a liner material recognized by the NSF (National Sanitation
Foundation, Standard 54).
5. The FML will be certified as “holiday free” by electrical potentiometric
means (spark tested) during manufacture.
6. Adequate slack will be maintained in the liner material during assembly
and installation to minimize stresses due to variations in ambient
temperature and incident radiation.
7. Heavily creased or otherwise defective liner material must be rejected.
8. Testing of coupons (strips of material) before seaming, stress cracks and
all seams must be done in accordance with the manufacture’s
requirements.
9. Installation of the FML will ideally take place in temperatures ranging
from 40 degrees Fahrenheit to 110 degrees Fahrenheit. In the event that
the FML is installed during colder conditions (between 20 degrees
Fahrenheit and 40 degrees Fahrenheit) the cold weather seaming
procedures detailed in FML QA/QC, Attachment E, shall be followed.
10. Air Vents will be installed on all four sides of the Containment Basin as
detailed in Attachment E and Compaction of the anchor trench backfill
will provide a firm unyielding surface to secure the FML along the berms.
GEM ENGINEERING,INC.
AttachmentD – Specifications andQA/QCforHDPELiners
Specifications andQA/QCforHDPELiners
1
1.0 SCOPE
1.1 ThesespecificationsdescribeHighDensityPolyethylene(HDPE)LiningMembranes.The
supplyandinstallationofthesematerialsshallbeinstrictaccordancewiththeEngineer’s
specificationsandengineeringdrawingsandbesubjecttothetermsandconditionsofthe
contract.ThesubgradeandtheHDPEmaterialwillmeetthespecificationscontainedhereinand
intheGRITest MethodGM13.
2.0 MATERIAL
2.1 PhysicalProperties:
A.TheHDPElinermaterialusedinthisprojectshallbeaminimumof60milinthickness
andhavethepropertiesascalledoutinTable1(a)ofGRITestMethodGM13
(AttachmentG).
B.Rawmaterialshallbefirstqualitypolyethyleneresincontainingnomorethan2%clean
recycled polymerbyweight.
C.MeltIndex(ASTMD1238Condition 190/2.16):<= 1.0g/ 10 min.
D.Dimensional stabilityineach directionat+/-2%max(ASTMD 1204 – 100oC 1 hr).
E.Environmental stresscrackresistance of 1500 hrsmin(ASTMD 1693 ConditionB).
F.ThenewmembranelinershallcompriseHDPEmaterialmanufacturedofnew,first-
qualityproductsdesignedandmanufacturedspecificallyforthepurposeofliquid
containmentinhydraulic structures.
G.Theliningmaterial shall bemanufacturedaminimum of 22.5 feet seamlesswidths.Labels
ontherollshallidentifythethickness,lengthandmanufacturer’srollnumber.Thereshall
be no factory seams.
H.Thelinermaterialshallbesoproducedastobefreeofholes,blisters,undispersedraw
materials,oranysignofcontaminationbyforeignmatter.Anysuchdefectshallbe
repairedusingtheextrusion fusionwelding techniquein accordancewith the
manufacturer’srecommendations.
I.Thecontractorshall,atthetimeofbidding,submitacertificationfromthemanufacturer
ofthesheeting,statingthatthesheetingmeetsphysicalpropertyrequirementsforthe
intendedapplication.FMLrollswillnotbeinstalled,ifanytestedpropertyisbelowthe
NationalSanitationFoundation(NSF 54)minimum standard.
2.2 Handling:
A.Delivery:Transportationofthegeomembraneshallbeperformedbythegeomembrane
manufacturerthroughanindependenttruckingfirm or other partyasagreedbythe owner.
Specifications andQA/QCforHDPELiners
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B.Offloading:Geomembrane,whenoff-loaded,shallbeplacedonasmoothwelldrained
surface,freeofrocksoranyotherprotrusionswhichmaydamagethematerial.Nospecial
coveringisnecessaryforgeomembraneThefollowingshouldbeverifiedpriortooff-
loadingthegeomembrane:
1.Handlingequipmentusedonthesiteisadequateanddoesnotposeanyriskof
damagetothegeomembrane.
2.Personnelinformed ofproper handlingtechniquesandwill do so withcare.
C.Anyweldingroddeliveredtothesitepriortothegeomembraneinstallationcontractor’s
arrival should be keptcoveredanddry or placedina storagefacility.
D.Uponarrivalatthesitethegeomembraneinstallationcontractorshallconductasurface
observationofallrollsfordefectsandfordamage.Thisinspectionshallbeconducted
withoutunrollingrollsunlessdefectsarefoundorsuspected.Thegeomembrane
installationcontractor shallindicateany damagetotheProject Manager/Owner.
E.Storage:TheProjectManager/Ownershallprovidestoragespaceinalocation(s)such
thaton-sitetransportationandhandlingareminimized.Storagespaceshouldbeprotected
fromtheft, vandalism, passage of vehicles,and beadjacenttotheareato belined.
3.0 MANUFACTURER
3.1 Experience:Themanufactureroftheliningmaterialspecifiedintheprevioussectionshallhave
previouslydemonstratedtheabilitytoproducethismembranebyhavingsuccessfully
manufacturedaminimumoftenmillionsquarefeetofsimilarlinermaterialfor hydrauliclining
installations.ThelinermaterialprovidedbythemanufacturermustbelistedbytheNSF
(NationalSanitationFoundation)Standard 54.
3.2 FactoryQualityAssurance andControl
A.QualityAssurancetestingshallbecarriedoutbythegeomembranemanufacturerto
demonstratethatthe productmeetsthis specification.
B.RawMaterial:AllcompoundingredientsoftheHDPEmaterialsshallberandomly
sampledondeliverytotheHDPEmanufacturingplanttoensurecompliancewith
specifications.TeststobecarriedoutshallincludeDensityASTMD1505andMeltIndex
ASTMD1238,Condition E.
C.ManufacturedRollGoods:Samplesoftheproductionrunshallbetakenandtested
accordingtoASTMD638toensurethattensilestrengthatyieldandbreak,elongationat
yieldandbreakmeettheminimumspecifications.Aqualitycontrolcertificateshallbe
issuedwiththematerial.
D.Allweldingmaterial shall be ofatype suppliedbythemanufacturer.
Specifications andQA/QCforHDPELiners
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E.AllFMLmaterialshallbecertifiedas“holidayfree”byelectricalpotentiometricmeans
(sparktested)or otherequivalentapprovedmeans, duringmanufacture.
3.3 Submittals:Thegeomembranemanufacturershallsubmitthefollowinginformationtothe
Project Manager/Owner:
A.Theorigin(resinsupplier’sname,resinproductionplant),identification(brandname,
number)andproduction date ofresin.
B.Acopyofthequalitycontrolcertificatesissuedbytheresinsuppliernotingresultsof
densityandmeltindex.
C.Reportsonthetestsconductedbythegeomembranemanufacturertoverifythequalityof
theresinusedtomanufacturethegeomembranerollsassignedtotheconsideredfacility
(thesetestsshouldincludespecificgravity[ASTMD792MethodAorASTM1505and
meltindexASTMD1238Condition 1902.16]).
D.Reportsonthesetestsconductedbythegeomembranemanufacturertoverifythequality
ofthe sheet.
E.Apropertiessheetincluding,ataminimum,allspecifiedproperties,measuredusingtest
methodsindicatedinthe specifications orequivalent.
F.Afterreceiptofmaterial,thegeomembranemanufacturershallprovidetheProject
Manager/OwnerwithonequalitycontrolcertificateforeveryrollofFMLprovided.The
qualitycontrolcertificateshallbesignedbyaresponsibleparty.Thequalitycontrol
certificateshallinclude:rollnumbers,identificationandresultsofqualitycontroltests.As
aminimum,thequalitycontrolcertificatesshallincludetheresultsofthegeomembrane
propertiestestedbythemethodandatthefrequency showninthetable below.
Property TestMethod Frequency
Thickness ASTMD 751 EveryRoll
Density ASTMD 792/1505 Every 5th Roll
TensileYieldStrength ASTMD 638 EveryRoll
Yield Elongation ASTMD 638 EveryRoll
TensileBreakStrength ASTMD 638 EveryRoll
Break Elongation ASTMD 638 EveryRoll
DimensionalStability ASTM 1204 EveryRoll
TearResistance ASTMD 1004 EveryRoll
PunctureResistance FRMS 101C-2065 EveryRoll
EnvironmentalStressCrackResistance ASTMD 1693B EveryRoll
CarbonBlackContent ASTMD-1603 Every 5th Roll
CarbonBlackDispersion ASTMD-3015 EveryResinLot
Specifications andQA/QCforHDPELiners
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4.0 INSTALLATION
4.1 AreaSubgradePreparation:Theearthworkcontractorshallberesponsibleforpreparingthe
subgradeaccordingtothebasin’sdesignandinaccordancewiththefollowingspecifications.If
thereisadiscrepancybetweentheprojectdesigndrawingsandthefollowingspecificationsthe
more stringentrequirements shallapply.
A.Theearthworkshallbesmoothandfreeofallrocks,stones,sticksroots,sharpobjects,or
debrisofanykind.Nostonesorotherhardobjectsthatwillnotpassthrougha3/8”screen
shallbepresentinthetop1”ofthesurfacestobecovered.Novegetation,brushrootsor
otherforeignmaterial shall be present on the surfacesto belined.
B.Thesurfaceshouldbecompactedsoastoprovideafirm,unyieldingfoundationforthe
membranewithnosudden,sharporabruptchangesorbreakingrade.Noruts,
irregularitiesorsoftareaswillbepresentonthesurfacestobelined.Thesubgradeshall
bethoroughlycompacted.
C.No standingwaterorexcessivemoisture shall beallowed.
D.AnanchortrenchshallbeconstructedinasquareinaccordancewithdetailDF3/C.DF3
to securetheFMLalongthe berm ofthecontainment structureto becovered.Seeattached
drawingsatendofthis specificationforanchorandcover details.
E.Theinstallationcontractorshallcertifyinwritingthatthesurfaceonwhichthemembrane
istobeinstalledisacceptablebeforecommencingwork.TheFMLwillbeassembled,
seamed,testedandinstalledbythemethods specifiedbyamanufacturerrecognizedbythe
NationalSanitationFoundation,Standard 54.
F.The subgrade shall beconstructed so astomeetthefollowing:
1.The subgradematerialwillcomefromeither on-site orfromapproved stockpiles.
2.Theearthworkfortheanaerobicdigestersandtheequalizationbasinswillbe
constructedsothesubgradewillbefreeofanyforeignmaterialsuchasstonesgreater
than3/8inchindiameter,vegetation,brush,rootsorsimilarmaterialwhichcould
damagetheFML.
3.ThesubgradematerialwillbeclassifiedasCH,CL,CL-ML,ML,SM,SC,SWorSP
bytheUSCSClassificationSystem.
4.Amoisture/densitycurvewill be developedforthe subgradematerial.
5.Theminimumcompactedthickness ofthe subgradelayer shall be 8”.
6.Thesubgradewillbecompactedandgradedtomeettheinstallationcontractor’s
specificationssoastoavoidanyruts,irregularitiesandsoftareas.Thesubgradewill
bethoroughlycompactedto provide supportfortheFML.
Specifications andQA/QCforHDPELiners
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7.Thesubgradewillbecompactedtoaminimumof90%drydensity.Forproper
compaction,moisturewill beaddedtothe soilin quantitiescomparabletotheOMC.
8.Installeddensityshallbeconfirmedbyfieldtestmethodsatafrequencyofonetest
per 200’x 200’ grid square.
9.Awrittenstatement byanindependentprofessionalengineerregardingthesubgrade’s
structuralintegrity,alongwithsupportingdatawillbesubmittedwiththeliner
certification packet.
4.2 DikeConstruction:Theearthworkcontractorshallberesponsibleforconstructingdikes
accordingtothefollowing specifications:
A.The dikewill beconstructed ofrelativelyimpermeablematerial.
B.Eachlift shall notexceed 6 inchesin depth.
C.Ageotechnicalinspectorwillconductcompactiontestingforeachtwoverticalfoot
intervalsatafrequencyof 1 perevery 400 linearfeet.
D.Awrittenstatementbyanindependentprofessionalengineerregardingthedike’s
structuralintegrity,alongwithsupportingdatawillbesubmittedwiththeliner
certification packet.
4.3 AnchorTrench:
A.TheattachedschematicdetailDF3/C.DF3attheendofthisspecificationindicatesthe
anchortrenchinstallation.Deviationsfromthisdesignmustbeapprovedbythedesign
engineerpriorto use.
B.Compactionoftheanchortrenchbackfillingwillbedonepromptlyafterinstallationofthe
FML.
C.Compactionofthetrenchbackfillshallincludemoistureaddedtothetop6inches,with
compaction donebya vibratoryrollerortampertofirm unyielding surface.
D.Finalgradingwillbeimplementedtoproduceasmoothuniformfinishthatslopesaway
fromthe digesterand basins.
E.Aclientapprovedqualitycontroltechnicianshallinspecttheanchortrenchupon
completion.Anyportionoftheanchortrenchinadequatelyconstructedwillbere-dugand
repairedinaccordancewiththe specificationsabove.
4.4 GeomembranePlacement:
A.TheinstallationoftheHDPEmustbedonebythemanufacturer,oramanufacturer’s
authorizeddistributor,usingthemanufacturer’sextrusionorhotwedgewelding
equipmentandinstallationmethods.Allsupervisorsoverseeingthelinerinstallationmust
Specifications andQA/QCforHDPELiners
6
havefivemillionsquarefeetofsupervisorylinerexperience.Allfieldtechniciansmust
have onemillion squarefeet of seamingexperience.
B.FieldPanelidentification:Afieldpanelistheunitareaofpolyethylenewhichistobe
seamedinthefield,i.e.,afieldpanelmaybeacompleterollorpartialrollcutinthefield.
Smallerunitsusedintheliningsystemssuchasrepairs,tabs,extensions,etc.neednotbe
documentedinthe samemannerasafield panel.
1.Theinstallerwillberesponsibleformarkingeachpanelwiththeidentification
numberandtheappropriatemanufacturer’srollnumber.Itissuggestedthatthepanel
numberbemarkedoneachendofthepanel,aftereachpanelisplaced,foreaseof
reference.
C.FieldPanelPlacement:
1.PlacementPlan:Panelplacementshouldtakeintoaccount:sitedrainage(including
sumporlowpointconsiderations),prevailingwinddirection,subgradeconstruction,
accesstothesiteandtheproductionscheduleoftheproject.Adequateslackwillbe
maintainedinthelinermaterialduringassemblyandafterinstallationtominimize
stress dueto variationsinambienttemperatureandincidentradiation.
2.InstallationSequence:Fielddeployedpanelsshouldbeseamedassoonaspossible
afterdeploymenttominimizetherisk ofwind orwater damage.
3.WeatherConditions:Geomembranepaneldeploymentshallnotproceedwhen
ambientairtemperatureoradverseweatherconditionsexistwhichwilljeopardizethe
integrityofthelinerinstallation.Typically,installationshallnotproceedwhenthe
ambienttemperatureisbelow20oForabove110oF.Speciallowtemperaturewelding
techniquesmayberequiredinconditionsofambienttemperaturesbetween20oFand
40oF.
4.Geomembranepaneldeploymentshallnotproceedifsubgradeconditionshave
deterioratedduetomoisture,orinthepresenceofhighwindswhichmightcause
damagetothelinermaterial.Deployedpanelsshouldbeadequatelyballastedatall
timestolimittherisk ofwind damage.
5.MethodofDeployment:TheFMLinstallationcontractorshallproceedwith
deploymentprovidedthefollowingconditionsaremet.Iftheconditionsbeloware
notmettheFMLinstallationcontractorshallceasedeploymentandresolvethe
problemswiththeProject Manager/Owner.
·Anyequipment used does not damagethe subgrade.
·The subgradeconditions have not deteriorated.
·The subgradeisfree oflooserocks, debris,ruts,etc.
·Thepersonnelwhoareincontactwiththelinerdonotsmokewear
damagingshoesorengageinotheractivitieswhichriskdamagetothe
liner.
Specifications andQA/QCforHDPELiners
7
·Adequatesandbagsarepresenttoweighttheedgesofthelinertoavoid
wind uplifting.
·Excessivetrafficacrossthelinerisavoided.
6.Damage:TheFMLinstallationmanagerandqualityassurancetechnicalshallvisually
inspecteachpanel,assoonaspossibleafterdeployment,fordamageorareasneeding
repair.Appropriatemarksindicatinganeedforrepairsshallbedoneduringthe
inspection.Heavilycreased or otherwise defectivematerial shall berejected.
4.5 FieldSeaming&Layout:
A.Individualpanelsoflinermaterialshallbelaidoutandoverlappedbyamaximumoffour
inches(101millimeters)forextrusionweldpriortoweldingorfiveinches(127
millimeters)forhotwedgeweldpriortowelding.Extremecareshallbetakenbythe
installer in the preparation of the areas to be welded.
Allsheetingshallbeweldedtogetherbymeansofintegrationoftheextrudatebeadwith
theliningmaterial.Thecompositionoftheextrudateshallbeidenticaltothelining
material, orall sheetingshall beweldedtogetherusingthe hotwedgeweldingsystem.
B.SeamLayout:Ingeneral,seamsshallbeorientedparalleltotheplaneofmaximumslope,
i.e.,orientedalong,notacrosstheslope.Incornersandoddshapedgeometriclocations
thenumberofseamsshouldbeminimized.Nohorizontalseamsshouldoccuronapanel
lessthan5linealfeetfromthetopoftheslope.Onslopesoflessthan10%(6:1)thisrule
shall notapply.Seamswill beinstalledatleastfourfeetintotheanchortrench.
1.Aseamisconsideredaseparateentityifitjoinstwopanels.Repairsarenot
considered seamsinthiscontext.
2.Aseamnumberingsystemcanbeusedtoidentifytheseams.Itissuggestedthata
simple numericalsystembe usedoradjacentpanel numberscan be utilizedtoidentify
the seam.
3.Seamswill beweldedtoatleastfourfeetintotheanchortrench.
C.Seaming EquipmentandProducts:Approved processesforfield seamingandrepairingare
extrusionweldingandfusionwelding.Allweldingequipmentshouldhaveaccurate
temperaturemonitoringdevicesinstalledandworkingtoensurepropermeasurementof
thefusionweldingwedgetemperature ortheextrusion barreltemperature.
D.ExtrusionWeldingProcess:Thisprocessshallbeusedprimarilyforrepairs,patchingand
special detailfabricationandcanalso be usedforseaming.
1.Theextrusionweldingapparatus(Handwelder)shallbeequippedwithgaugesor
othertemperaturemonitoringdevicestoindicatetemperatureoftheextrudate(resin)
aswellastheapplicablepre-heat settings.
2.TheFMLinstallationcontractor shall verifythefollowing:
Specifications andQA/QCforHDPELiners
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a.Equipmentin useisfunctioning properly.
b.Weldingpersonnelarepurgingthemachineofheat-degradedextrudatepriorto
actual use.
c.Allworkbythepersonnelisperformedoncleansurfacesanddoneina
professionalmanner.
d.No seamingis doneinadverseweatherconditions.
E.FusionWeldingProcess:Thisprocessshallbeusedforseaming panelstogetherandisnot
generally usedfor patching ordetailwork.
1.Theapparatusmaybeofahotwedgetypeandshallbeequippedwitha“split
wedge”, usedforpressuretype seamtesting.
2.Fusionweldingequipmentshallbeself-propelleddevicesandshallbeequippedwith
functioningspeedcontrollersandmonitorstoassurepropercontrolbythewelding
technician.Theweldingequipmentusedshallbecapableofcontinuouslymonitoring
andcontrollingthetemperaturesinthezoneofcontactwherethemachineisactually
fusingtheliningmaterialsoastoensurethatchangesinenvironmentalconditions
will notaffecttheintegrityoftheweld.
3.TheFMLinstallationcontractor shall verifythefollowing:
a.Equipmentin useisfunctioning properly.
b.Weldingpersonnelareperformingseaminginaprofessionalmannerandare
attentivetotheir duties.
4.FigureF-1 belowisaschematicdetailwhichindicatesacceptablefusionweld.
Deviationsfromthesemust beapprovedbythedesignengineerpriorto use.
4"TO6"
AIRPOCKETFUSIONHEAT
WELDS(TYP.)FLEXIBLE
MEMBRANE
LINERMATERIAL
FigureF-1 – TypicalFusion Weld
Specifications andQA/QCforHDPELiners
9
F.SeamPreparation:Theareatobeweldedshallbecleanedandpreparedinaccordance
withthisspecificationandtherecommendationsofthematerialmanufacturer.The
weldingtechnician shallverifythefollowing:
1.Priortoseamingtheseamareashallbefreeofmoisture,dust,dirt,sandordebrisof
anynature.
2.Seamis overlappedforfusionwelding.
3.Seemisoverlappedorextendedbeyonddamagedareasatleast4”whenextrusion
welding.
4.Seamis properly heattackedandabradedwhentheextrusionweldingis done.
5.Seamsareperformedwiththefewestnumberofunmatchedwrinklesor“fish
mouths”.
G.FishMouths:No“fishmouths”shallbeallowedwithintheseamarea.Where“fish
mouths” occurthematerial shall becut, overlappedandan overlapextrusionweld shall be
applied.
H.Slack:Adequateslackwillbemaintainedinthelinerduringassemblyandafter
installationtominimizestressesduetovariationsinambienttemperatureandincident
radiation.
I.Defective Material:Heavilycreasedor otherwisedefectivelinermaterialwill berejected.
J.WeatherConditionsforSeaming:Noseamingshallbeperformedinambientair
temperaturesoradverseweatherconditionswhichwilljeopardizetheintegrityoftheliner
installation.Ambientairtemperaturesshallnotexceed110oFnorbebelow20oFduring
seaming.Additionally,seamingshallnotproceedinconditionsinwhichthelineris
subjectto dew or othercondensation,rain, snow,frost orfrozen subgrade.
K.LowTemperatureWeldingProcedures:Themostimportantcriteriaforperforming
weldingwhentheambienttemperatureisbetween 20oFto 40oFisthecondition ofthetrial
weld.Alltrialweldsshouldbemadeinconditionsduplicatingtheactualwelding
environment.Thefollowingproceduresshouldbeusedtomaintainthequalityoftheweld
inlowtemperatureambientconditions(20oFto40oF).
1.Conductadditionaltrialweldswhenaweldingmachinehasbeenshutoff,oraftera
majorchangeinambientconditions.Amajorchangeinambientconditionswould
include butis notlimitedtothefollowing:
a.Changeintemperature ofmorethan 20oF
b.Changeinwind speed ofmorethan 10 mph.
c.Changeintheamount ofsunshine on theliner.
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2.Thegeomembraneandextrudatematerialmustbedryandfreefromfrost,dew,
condensation or othermoisture.
3.Hotwedgesettemperaturesmaybeincreasedupto700oFin10oFincrementsas
necessary.
4.The hotwedgerate oftravel should be slowedasnecessary.
5.Lengthoftrialweldseamsshouldbeincreasedto5ftforextrusionweldsand24ft
forfusionwelds.
6.Cleantheseamareaimmediatelyinfrontoftheweldingapparatuswithacleandry
cloth.
7.Destructivelytestonespecimen,nogreaterthan6”fromtheendofeachseamto
confirmthe quality ofthe seam.
8.Increasehandwelder(extrusionwelder)pre-heattemperatureupto600oFin20oF
incrementsas necessary.
9.Increasehandwelderextrudatetemperatureupto530oFin10oFincrementsas
necessary.
10.Ifadditionalmeasuresareneededtoproduceacceptableweldsthefollowing
additionalmeasuresmaybeimplemented:
a.Installaninsulatingmaterialsuchasageotextilecushionbeneaththeseambeing
welded.
b.Usehotairpre-heat(additionalpre-heatforextrusionwelding)6”to12”infront
oftheweldingapparatus(bothfusionandextrusionwelders).Verifyweldquality
bemeans ofatrialweld.
11.Iftrialweldsstillindicatethataqualityweldcannotbeproducedbetheabovesteps,
awindshieldoranenclosuremaybeplacedovertheareatobewelded.Inthecaseof
anenclosure,theenclosedareashallbeheatedbyforcedairorradiantmeanstoanair
temperatureat orabove40oF.
12.Alltrialweldswillbedocumentedwithsamples(failuresandapproved)recorded,
retainedwith samplesattachedtocompletion submittalrecords.
L.TemporaryBonding:TheFMLinstallationcontractorshallverifythatnosolventsor
adhesivesare usedintheseamingarea. Tape or heattackingis permissiblefortemporarily
holding patches butis nota substituteforwelding.
M.Trialseams/Welds:Trialseams/weldsshallbemadeonappropriatesizedpiecesof
geomembranematerialto verifythat seamingconditionsareadequate.
Specifications andQA/QCforHDPELiners
11
1.Trialseams/weldsshallbeperformedforeachweldertobeusedandbyeach
operator ofextrusionwelders,andbytheprimaryoperator ofthefusionwelder.
2.Apassingtrialseam/weldshallbemadepriortoseamingeachday.Iftheapparatus
iscooled downafter useandadditionaltrial seammayberequired.
3.Fusionweldedtrialseamsshallbeapproximately5footlongby1footwidewiththe
seamcenteredlengthwise.Forextrusionweldingthetrialseamsamplesizeshallbe
approximately 3 feetlongby 1 footwidewiththe seamcenteredlengthwise.
4.Testweldsshallbemarkedwithdate,ambienttemperatureandweldingmachine
number.Alltestweldsampleswillberetainedandsubmittedwithapproved
inspectionreports.
5.Samplesofweld¼”to½”wideshallbecutfromthetestweldandpulledbyhandin
peel. Theweld should not peel.
6.RefertoQualityAssuranceandQualityControlSection5.2.B fortesting
requirements.
7.Thegeomembraneinstallationcontractorshallassigneachtrialseam/weldsamplea
numberandrecordthetestresultsintheappropriatelog.
8.Uponpassing,unlessotherwisespecified,alltrialseam/weldspecimensmustbe
retainedand submittedwithapprovalinspectionreports.
4.6 Defects andRepairs
A.OncedefectiveorareasrequiringrepairareidentifiedascalledoutinSection5.3.Each
area shall berepairedinaccordancewiththis sectionand non-destructivelytested.
B.RepairProcedures:Anyportionofthepolyethyleneliningsystemexhibitingadefect
whichhasbeenmarkedforrepairshallberepairedwithoneormoreofthefollowing
appropriateprocedures:
1.Repair Methods:
·Patching:Usedtorepairholes,tears, un-dispersedrawmaterialsinthe sheet.
·GrindandRe-Weld:Usedtorepair small sectionofextruded seams.
·SpotWelding:Usedtorepair small,minor,localizedflaws.
·FlapWelding:Usedtoextrusionweldtheflapoffusionweldinlieuofafull
cap.
·Capping:Usedtorepairfailed seams.
·Topping:Application ofextrudate bead directlytoexisting seams.
2.Thefollowingconditions shallapplytoall oftheabovemethods:
a.Surfacesofthe polyethylenewhichareto berepaired shall beabraded.
Specifications andQA/QCforHDPELiners
12
b.All surfacesmust becleanand dryatthetime oftherepair.
c.Allseamingequipmentandpersonnelusedinrepairingproceduresshallbe
qualifiedand documentedbytheclient’sthird partyinspector.
d.Allpatchesandcapsshallextendatleast4”beyondtheedgeofthe defectandall
patches shall haveroundedcorners.
C.LargeWrinkles:Largewrinklesthatremaininthesheetasaresultoftemperature
expansionorunevensurfacepreparationmayneedremovalinconsiderationofapplied
deadloadsonthewrinkle,etc.Shouldthewrinkleneedremoving,thelowerdownslope
edgeofthewrinkleshallbecut,overlappedandrepairedasdescribedabove.Bothendsof
thewrinklerepairshallbepatched.Cautionmustbetakeninremovinganywrinkles.
Wrinklesareneededtoallowforfuturecontractionofthegeomembrane,especiallyin
coldweather.
4.7 LinerVents
A.TheattachedschematicdetailDF4A/C.DF4depictsatypicalvent.Ventsshallbe
installedinaccordancewithmanufacturer’srecommendationsaswellasrequirementsand
recommendationsindicated on project design drawings.
4.8 PipePenetrations
A.TheattachedschematicdetailDF4B/C.DF4depictsapipepenetration.Pipepenetrations
shallbeinstalledinaccordancewithmanufacturer’srecommendationsaswellas
requirementsandrecommendationsindicated onproject design drawings.
4.9 FinalEarthwork,BackfillingandEquipment
A.BackfillingofAnchorTrench:PromptlyafterinstallationoftheFML,theanchortrench
shallbe backfilledbytheearthworkcontractorortheinstaller,asspecifiedinthecontract.
Backfillingshouldoccurwhenthegeomembraneisinitsmostcontracted(taut)state.
Caremust betakenwhen backfillingtoavoiddamagetotheFML.
B.ConstructionEquipment:Constructionequipmentorvehicleswithsteeltracksshallnotbe
permitteddirectlyonthegeomembraneliner.Vehicleswithrubbertires,withoutatugged
treadandwithaloadingoflessthan6.0lbs/in2 weightareallowed,providedpropercare
istakenwhenoperatingthevehicletoavoidstressingthegeomembrane.Otherequipment
suchasportablegeneratorsshallbepermittedifthesupportapparatusfortheequipment
protectsthelinerfrom being damaged.
Specifications andQA/QCforHDPELiners
13
5.0 QUALITYASSURANCEANDQUALITYCONTROL
5.1 Materials:
A.TheFMLinstallationcontractororqualitycontroltechnicianshallverifythattheproperty
valuescertifiedbythegeomembranemanufacturermeetallofthespecifications;thatthe
measurementsofpropertiesbythegeomembranemanufacturerareproperlydocumented;
andthatthetestmethods usedareacceptable.
5.2 FieldSeamTesting/QualityControl
A.Theendusercompany,ortheirdesignatedrepresentative,reservestherightofaccessfor
inspection ofany orallphases ofthisinstallationattheirexpense.
B.Qualificationsofpersonnel:Allpersonnelperformingseamingoperationsshallbe
qualifiedbyexperience.Atleastonewelder(MasterWelder)shallbeonsiteatalltimes
duringthesealweldingprocessandhaveexperienceseamingaminimumof5,000,000ft2
ofgeomembrane.The“MasterWelder”shallprovidesupervisionofthelessexperienced
weldingtechnicians during seaming,patchingandtesting operations.
C.Testing ofcoupons(strips ofmaterial)before seaming, stresscracksandall seamsmust be
doneinaccordancewiththeFMLmanufacture’srequirements.
D.TrialWelds/Seams:
1.Fourspecimens,each1”wideand6”apartfromeachothershallbecutfromthetrial
seam.Twoofthespecimensshallbetestedinshearandtwospecimenstestedinpeel.
Bothshearandpeeltestsshallbeconductedtotheyieldpointofthegeomembrane.
Whentestingafusionweldedseamtheoutside(top)weldofasplit-wedgeweld
shouldbeconsideredtheprimaryweldandshallbetheweldtestedinpeel.The
specimenmustexhibitthefollowingpropertiestopass:
a.ShearTest:Bothspecimensmustmeetorexceedthebondedseamstrength
valuesinshearofbothspecimensshallexhibitabondedseamstrengthinshear
thatisgreaterthan90%oftheminimumyieldtensilestrengthoftheparent
material.
b.PeelTest:Bothspecimensmustexhibitfailureoftheparentmaterialormeetor
exceedthebondedseamstrengthvaluesinpeel,orstrengthvaluesshallbe
greaterthan 70% oftheminimumyieldtensile strength ofthe parentmaterial.
2.Generalseamingoperationsmayproceedpriortothetestbeingcomplete.Shoulda
trialseamfail,asampleshallberemoved3linealfeetfromthestartoftheseaming
operationsandtestedpertheabove.Thisprocedurewillberepeatedandfollowed
untilapassingsampleislocated.Allworkprecedingthepassingsampleshallbe
repaired.
Specifications andQA/QCforHDPELiners
14
E.Non-DestructiveSeamContinuityTesting
1.Concept:TheFMLinstallationcontractorshallnon-destructivelytestanddocument
allfieldseamsovertheirfulllengthusinganairpressuretestorvacuumtest.The
purpose of non-destructivetestsistocheckthecontinuity ofthe seams.
2.TheFMLinstallationcontractor shall:
a.Scheduleall non-destructivetesting operations.
b.Instructthetestingpersonnelregardingmarkingofrepairsneeded,leaksand
sign-offmarks on seamsandrepairs.
c.Monitortheoperationsoftestingpersonneltoensurethatproceduresfortesting
arefollowed.
3.Onseamsthatcannotbenon-destructivelytestedbyvacuumorair-pressuremethods
duetophysicalconstraints,(i.e.abootdetail)theseamshallbetestedusingother
approvedmethods.
4.Vacuum Testing:
a.Equipment:
·Vacuumboxassemblyconsistingofarigidhousing,atransparentviewing
window,asoftgasketingmaterialattachedtothebottom,avalveassembly
andacertified vacuumgauge.
·Vacuum pumpingdevice.Includingback-updevice
·Foamingagentin solution.
·Equipment suitableforapplyingthefoamingagent.
b.Procedure:
·Wetthe section ofthe seamwithfoamingagent.
·Placethe vacuum box overthewettedarea.
·Energizethe pumpingapparatus.
·Obtainaminimum pressure of-5.0 psi.
·Foraperiodofapproximately10seconds,observe,throughtheviewing
window,forthe presence of soap bubbles.
·If no bubblesare observed,repositionthe box on the nextareafortesting.
·Ifbubblesaredetected,markanddocumentlocationoftheleaksorepairscan
bemade.
5.AirPressureTesting:Thefollowingproceduresareapplicableforseamsproduced by
a double-fusionweldingapparatus.
Specifications andQA/QCforHDPELiners
15
a.Equipment:
·Airpumporairtankequippedwithpressuregageandcapableofproducing
pressuresbetween 25 to30 psi.
·Sharp hollow needletoinserttheairintotheairchamber oftheseam.
b.TestingProcedure:
·Installerwillprovideforapprovaladetailedseamtestingmappriortothe
starting ofsealtests.
·Seal bothends oftheairchannelinthe seamto betested.
·Insertthehollowneedleintotheairchamberateitherendoftheseamtobe
tested.
·Energizetheairpumptoapressurebetween25and30psiandreadpressure
insertedintothechamber.Allowthepressuretostabilizeandifnecessary,re-
pressurizeto between 25and 30 psi. Thenrecordthe pressure.
·Waitforaminimum of 5 minutesandthenrecordtheair pressureagain.
·Ifthedifferencebetweentheinitialandthefinalpressureisgreaterthan4psi
the seamfailed.Documentationrequired on allfailedtests.
·Uponcompletionofallreadings,opentheoppositeendoftheseamwitha
needle.Theescapingairwillconfirmthattheentirelengthoftheseamwas
pressurizedandthereforetested.
·Upon passingtheair pressuretest,the seam shallbemarkedand documented.
·AllSeamtests shall bewitnessedbyclient orclientsinspector.
c.ProcedureforAirPressure TestFailure:
·Whiletheseamair-channelisunderpressure,traversethelengthoftheseam
andlistenfortheleak.Oncetheareaoftheleakhasbeennarroweddown,
applyasoapysolutiontotheseamedge(donottrimexcessmaterialfrom
edge of seam)and observefor bubblesformedbyescapingair.
·Asanalternativetothestepabovetheseammaybere-testedinprogressively
smallerincrements, untilthearea ofleakageisidentified.
·Repairtheidentifiedleakingareabyextrusionweldingtheexcessmaterialat
theedge oftheseamandthen vacuumtest.
·Inareaswheretheairchannelisclosedandtheintegrityoftheweldisnot
suspect, vacuumtestingisacceptable.
F.DestructiveSeamTesting
1.Concept:Destructiveseamtestsshallbeperformedatlocationsselectedbyclient’s
inspectors.Thepurposeofthesetestsistoevaluatebondedseamstrength.Seam
strengthtesting shall beperformedand documentedaswork progresses.
2.LocationandFrequency:Theminimumfrequencyofsampleremovalshallbeone
sampleper750ftofseam.Thelocationofthetestsamplewillbetakennogreater
than 6”fromtheend ofthe seam.Additionaltestsamplesremovalasrequestedbythe
client orclient’sinspector.
Specifications andQA/QCforHDPELiners
16
3.SizeofSamples:Thesizeofthesampleforindependenttestingshallbe12”by
minimallengthwiththeseamcenteredlengthwise.Thesampleshallbecutintothe
following segmentsanddistributedasfollows:
a.Thefirstsegmentcutshallbe12”x12”markedwiththeappropriateD/Snumber
andgiventotheAQtechnicianfortesting.
b.Thesecondsegment,12”xrequestedlength(18”max)shallbemarkedwiththe
appropriateD/S numberandtransmittedatthecontractorscosttothe
independenttestinglaboratoryorthequalityassurancetechnicianpersonnelfor
their dispersal.
4.FieldTesting:Thesegmentsgiventothequalityassurancetechnicianshallbetested
in peelandin sheer usingthefollowingcriteria:
a.Ten specimens of1”width shall becutfromthesegment.
b.Fiveofthespecimensshallbetestedinapeelconfiguration.Theoutside(top)
weldofasplitwedgeweldshallbeconsideredtheprimaryweldandshallbethe
weldtestedin peel.
c.Five ofthe specimens shall betestedina shearconfiguration.
d.Thegeomembranemanufacturershallsupplyafieldtensiometerequippedwitha
drive/pullapparatusadjustedtoapullrateof 2”/minto20”/minandameansof
measuringthe strength ofthe sample.
e.PassFailCriteria: Theinstallers samplewill passwhen:
·The peel specimensexhibitfailure ofthe parentmaterial.
·Thebondedstrengthpeelvaluesshallbegreaterthanorequalto70%ofthe
minimumyieldtensile strength ofthe parentmaterial.
·The shear specimens displayparentmaterialfailure.
·Ifthebondedseamstrengthinshearvaluesisnotlisted,theshearvaluesshall
begreaterthanorequalto90%oftheminimumyieldtensilestrengthofthe
parentmaterial.
Note:Locusofbreakdeterminationsistobeinaccordancewith
ANSI/NSF 54
·Four out offive specimensmeetingtheabovecriteriaconstituteapassingtest.
f.ProcedureforFailingTests:
·Two samples ofthe same size shall beremovedfromthefailedseam. Thefirst
sampleshallberemoved10linealfeetinfrontofthefailedsampleandthe
second shall beremovedfrom behindthefailedsample.
·LabelthesamplesAandBandtestinaccordancewithprocedureslisted
above.
Specifications andQA/QCforHDPELiners
17
·IfbothsamplesAandBpass,seambetweenthelocationofsamplesAandB
shallhavetheflapextrusionweldedorbecappedandnon-destructivelytested
accordingly.
·IfeithersampleAorBfails,additionalsamplesshallbetakenaminimum
distanceof10feetawayfromthefailedtestlocation.Testingshallcontinueas
outlinedabove untilthearea ofincorrect seamisisolated.
·Inlieuoftakinganexcessivenumberof samples,theinstallermayoptattheir
costtoextrusionweldtheflaporcapfortheentirelengthoftheseamthen
non-destructivelytestthe seam.
·Allfailingtestsshallbedocumentedandforwardedtotheclientorclient’s
representativewithin 24 hours,alongwithrecommendation ofcorrection
5.3 Defects andRepairs
A.Identification:Allseamsandnon-seamareasofthepolyethyleneliningsystemshallbe
examinedfor defectsinthe seam or sheet.
B.Identificationofthedefectmaybemadebymarkingonthesheet/seamwithpaintorother
marks. Thefollowing procedure shall befollowed:
1.Foranydefectintheseamorsheetthatisanactualbreach(hole)largerthan¼”in
thelinersystem,theinstallerpersonnelshallcirclethedefectandmarktheletter“P”
insidethecircle. Theletter“P”indicatesthata patchisrequired.
2.Foranydefectintheseamorsheetthatislessthana¼”hole,theinstallerpersonnel
shallonlycirclethedefectindicatingthattherepairmethodmaybeonlyanextruded
beadandapatchmaynotnecessarilyberequired.Repairmethodswillbeatthesole
discretion oftheclientandtheclient’s qualifiedinspectionrepresentative.
C.Unlessotherwisespecified,onlythegeomembraneinstallationcontractororquality
assurancetechnicianshallbepermittedtomarkonthelinersystem.Thequalityassurance
technicianshallusemarkingsthataredistinguishablefromthegeomembraneinstallation
contractormarkings.
D.VerificationofRepairs:Eachrepairshallbenon-destructivelytestedinaccordancewith
requirementsofthesespecificationsandmanufacturer’srecommendations.Oncepassing
testsareachievedamarkingshallbeplacedontherepair,indictingthetestiscomplete
andtheareahaspassedthetest.Ifdefectsremain,appropriatemarkingsshallbemadeto
clearlyindicatethatadditionalrepairsarerequired.
5.4 FinalApproval
A.AfinalinspectionofthecompletedlinerwillbeconductedbytheFMLinstallation
contractor,qualityassurancetechnicianandprojectmanager/owner.Thiscareful
evaluationwilloccurbeforetheDivisionofWaterQualityisaskedtoapprovetheuseof
thelinedlagoon. The purpose oftheinspectionsisto verifythefollowing:
1.Allrepairs have beenappropriately performed.
Specifications andQA/QCforHDPELiners
18
2.Alltestresultsare positive.
3.Areaisfreeof scrap,trashand debris.
4.Anchortrench hasbeenproperly backfilled.
5.Linerhasbeeninstalledaccordingtotherequirementsofthesespecifications,the
project documentsandthemanufacturer’srecommendations.
6.Four(4)copiesinthreeringbindersofallinstallationrecorddocumentswillbe
required priortofinalacceptance.
B.Eachlinermaterialtest,constructioninspectionchecklist,datasheet,ornarrativereport
willbepreservedforinspectionbytheDivisionofWaterQuality.Wasteshallnotbe
dischargedintothedigestersorequalizationbasinspriortotheapproval oftheDivisionof
WaterQuality.
6.0 Warranty andGuarantee
6.1 Themanufacture/Installershallprovideawrittenwarrantyinaccordancewiththerequirements
specifiedbythe ownerand/ or designengineer.