APPENDIX G. Straddle Packer Testing Analysis

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1 APPENDIX G Straddle Packer Testing Analysis

2 JohnKozuskanichandMorganSchauerte 10/16/2009

3 CONTENTS 1.BOREHOLEHISTORY BOREHOLECAMERAOBSERVATIONS HYDRAULICTESTINGMETHODS RESULTS...4 APPENDIXA:BoreholeLogBH5...6 APPENDIXB:BoreholeCameraObservations...10 APPENDIXC:HydraulicTestingData...12

4 1.BOREHOLEHISTORY MonitoringboreholeMW5wasoriginallycoredbyG.E.T.DrillingonSeptember18,2006.Theborehole log(bh5,appendixa)indicatesthecoringequipmentusedwascme55,hqcore,andss.thelog indicatesthereis abovegradepiezometerstickupandcasingandnoscreen.lithologyandfracture locationsandremarksweremadeonbh5presumablybasedoncoreinterpretationbyarepresentative frommalroz. TheboreholewasinspectedpriortohydraulictestingbymembersofInteraEngineering(Michael Melaney)andQueen suniversity(johnkozuskanichandmorganschauerte).figure1isapicturetaken oftheboreholeonseptember15,2009.theboreholehadanunexpected3 dia.innermetalcasingand anadditional2 PVCriserwithintheouter4 dia.casingvisibleatsurface. 4 dia. steelcasing 3 dia. steelcasing 2 dia. PVCriser pressure transducer cement seal Figure1:OriginalMW5completionpriortothereamingoftheboreholetoremovethe2 dia.pvcriser andcementinsideofthe3 dia.casing. The2 PVCstandpipeandgroutsealtothe3 dia.innermetalcasingwersubsequentlyreamedoutof theboreholeduringoctober57,2009(subcontractedbyinteraengineering).thepurposeandlength of2 dia.pvcusedintheoriginalcompletionremainsunresolved.however,weestimateitlikelyonly 1

5 rantothebottomofthe3 dia.casing(roughly6.6m)basedonthesmallamountofpvcshavingsnoted onthegroundaroundtheboreholeandsittingatthebottomofthewell. 2.BOREHOLECAMERAOBSERVATIONS AsubmersibleboreholecamerawasinsertedintotheboreholeonThursday,October8,2009.The purposeofthisworkwastoverifythatthereamingoftheboreholehadadequatelyremovedthepvc pipeandgroutdowntotheinnersurfaceofthe3 dia.casing,andthattheboreholewasadequatefor hydraulictesting.someremnantsofconcretewerenotedonthewallsofthecasing.ingeneral,the boreholewallswereinfaircondition(roughinsomeplaces).itwasalsonotedthatthediameterofthe boreholewas3,not4 aswasoriginallythought.thenotesfromtheboreholecameraworkareshown infigure2alongwiththeoriginalobservationsfrombh5.allfeaturesarereportedwithrespectto groundsurface(mbgs=metresbelowgroundsurface,ftbgs=feetbelowgroundsurface).theborehole cameraobservationsarealsosummarizedintableformatinappendixb. 3.HYDRAULICTESTINGMETHODS HydraulictestingofMW5wasconductedonOctober89,2009.Constantheadtestingwastheoriginal proposedmethodona3mtestinginterval.however,thiswasabandonedbecausetheassemblywas notabletobeinsertedintothewellsafelywithoutgettingcaughtonthesidesoftheborehole (endangeringtheinflationlines,packerbladdersandpressuretransducerconnection).themethodwas changedtoslugtestingwithslugvolumesrangingbetween5and10l.thehydraulicheadwas monitoredandrecordedinrealtimeduringeachtestwithapressuretransducer(100psidruk)and datalogger. SlugtestswereanalyzedusingtheHvorslev(1951)method.Thetimehydraulicheadcurveswere correctedforthecasewhentheheadhadnotquitestabilizedpriortotheinjectionoftheslugusingan extrapolationoftheshutindata(figure3). Figure3:Baselinecorrectionmethodforslugtestsconductedpriortothestabilizationoftheshutin head.theunstablizaedshutincurve(a)isextrapolatedintime(b).thedifferencebetweenthe extrapolatedcurveandthebaseline(c)isthecorrectionfactorthatisaddedtotheslugresponsecurve. Thisadjuststhefinaldataset(d)torepresentthehydraulicresponseofthetestintervaltoslugonly. 2

6 Figure2:MW5boreholelithologyandcoreanalysis(MALROZ),boreholecameraobservations (KozuskanichandSchauerte)andhydraulictestingresults.Thecasingstickupabovegroundsurface is0.652m(notshownondiagram).thetotaltransmissivityoftheboreholeisapproximately2x10 5 m 2 /s. 3

7 AwholeopenholeslugtestwasalsoperformedtocomparetothetotalTcalculatedbydiscreteinterval slugtesting. Twodifferentpackerconfigurationswereused(Table1,Figure4). Table1:PackerassemblyconfigurationsusedtohydraulicallytestMW5. PackerAssembly1 PackerAssembly2 TestIntervalLength(m) Diameterofstandpipe 1.25 ( m) 2 (0.0508m) 4.RESULTS TheverticalprofileofboreholetransmissivityinMW5isshowninFigure2.Asummaryoftheanalysisis showninappendixc.therawdataandhvorslevanalysisdetailsforeachtestintervalcanbefoundin file:lansdownehydraulictestingmw5october2009.xlsx.thetotaltoftheboreholeestimatedby summingthepackertestresultsisapproximately2x10 5 m 2 /s. Thewholeholeslugtestdatacanalsobefoundinfile:LansdowneHydraulicTestingMW5October 2009.xlsx.Thetotaltestlengthisapproximately31.5m(38.5mbgstotaldepth 7mbgsstaticwater level).thetotaltoftheboreholeusingthismethodisestimatedtobeapproximately8x10 6 m 2 /s. Note:thelocationfracturethatmaintainstheheadofthewell~7mbgsremainsunresolved.The fracturesinthesandstoneallshowedlowershutinheadscomparedtothestaticwaterlevel.there maybeanotherhighheadfractureabovethelastintervaltested(#44)andbelowthebottomofthe casing.afracturewasnotnotedinthiszoneusingtheboreholecameraorinthecorelog.watermay alsobeshortcircuitingintothewellviaapoorcasingseal. 4

8 Figure4:StraddlepackerconfigurationsusedforslugtestinginLansdowneat MW5:1)straddlepackerconfigurationwithatestintervallengthof1.44mand theslugintroducedintotheintervalviaa2 dia.pvcriser,and2)straddlepacker configurationwithatestintervallengthof1.51mandtheslugintroducedintothe intervalviaa1.25 dia.pvcriser. 5

9 APPENDIXA:BoreholeLogBH5 6

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13 APPENDIXB:BoreholeCameraObservations 10

14 File:BH5LansdowneBoreholeCameraObservationsOct82009.xlsx TopofFeature BottomofFeature fbtoc ftbgs mbtoc mbgs fbtoc ftbgs mbtoc mbgs FeatureDescription casing fracturezone staticwaterlevel fracture fracturezone fracture largefracture fracture fracturezone fracture fracturezone fracturezone fracture subverticalfracture? fracture fracture fracture fracture fracturezone fracturezone fracture fracture fracture fracturezone subverticalfracture poorqualityofrockzone fracture fracture subverticalfracture subverticalfracture fracture fracture largefracture subverticalfracture/vein subverticalfracture/vein subverticalfracture/vein fracture subverticalfracture/vein fracture bottomofborehole FeatureDescriptionLegend: 1)Fracture:asinglefracture,2)FractureZone:aseriesofcloselyspacedfracturesoralargeopeningintheboreholewall,3)Subvertical Fracture:asinglefracturethatappearstointersecttheboreholeonanangle,4)SubverticalFracture/Vein:asinglesubverticalfractureor quartzinfilledvein,5)poorqualityofrockzone:azoneofboreholewherethediameterincreasesignificantlyandtherocksurfaceisrough. Casingstickup=0.652mags(metresabovegrondsurface),2.139ftags(feetabovegroundsurface). 11

15 APPENDIXC:HydraulicTestingData 12

16 HydraulicTestingResults MW5 Notes TestInterval TestDetails Results SingleFracture Date Test# top(mbtoc) bottom(mbtoc) top(mbgs) bottom(mbgs) length(m) InflationTime SlugTime SlugVolume(L) PackerAssembly Transmissivity(m 2 /s) logt(m 2 /s) Equivalent(microns) 16Oct :35 14: E Oct :21 14: E Oct :06 13: E slug1used,overlapswith41 16Oct :42 13: E Oct :08 13: E Oct :48 12: E Oct :59 14: E Oct :44 13: E Oct :22 13: E Oct :06 13: E Oct :52 12: E Oct :38 12: E Oct :23 12: E Oct :06 12: E Oct :52 11: E Oct :36 11: E Oct :17 11: E Oct :02 11: E Oct :48 16: E Oct :19 16: E Oct :25 11: E onlytoppacker 16Oct : E wholeholeslug 13