Appendix 2. Sub-bottom Profile

Sub-Bottom Profiling Survey Report

BabelanMuaraGembong,Bekasi,WestJava1

1. Introduction

1.1 GeneralThisworkwascarriedoutbyPT.QyudosGeosurveyIndonesiaforthepurposesofDepth InvestigationforGasandOilPipeline inCBLRiverArea,BabelanandMuaraGembong,Bekasi.Surveysofthiswork istheSubBottomProfilingSurvey(SBP). Inthisreportcontainstheresultsofasurveythathasbeencarriedout.Thefieldworkhasbeencompletedfor3daysfromAugust,6August,8,2014startfrommobilization,datacollectionuntilDemobilization,andthenfollowedbydataprocessingandpreparationofthefinalreport.

1.2 PurposeThepurposeofthissurveyistoobtaininformationonthedepthofoilandgaspipelinesthatcrossingthroughtheregion,especiallyBabelanCBLrivertoMuaraGembong,Bekasi.

1.3 ScopeThescopeofthisworkinclude:a.SurveyactivityCarryingoutSubBottomProfilingSurvey(SBP)Documentationofallsurveysactivitiesb.DataProcessingandInterpretationPerformSubBottomProfiling(SBP)dataprocessingPipelineDepthanalysisandinterpretationofSubBottomProfiling(SBP)data

Appendix 2 Sub-bottom profiling survey



1.4 ReportSystematic

Theresultsofthesurveyarepresentedintheformofareportwiththefollowingcomposition:

a.Introductionb.Locationc.ImplementationofSurveyandDataProcessingd.Resulte.Conclusionf.Appendix




2. Location2.1 SurveyArea

ThelocationisontheCBLRivertoMuaraGembong,Bekasi.Corridorlocation inUTM isX:9322000.00 9331500.00 and Y:718000.00 728500.00. Location of the survey area can be seen in Figure 1. islocatedatBabelantoMuaraGembong,Bekasi,WestJava.

Ficture1.Surveyarea(redline)




3. Survey Implementation and DataprocessingThisworkusesmultiplestagesincludingpreparation,ImplementationandDataProcessing.3.1 PreparationPhase

The preparation phase consists of coordinating with stakeholders,secondarydatacollectionandpreparationofequipmenttobeused.3.1.1 SecondaryDataCollection

Prior to the survey conducted, the team first conductpreliminary surveysand secondarydatacollection. Itaims toobtainapictureandadditional informationontheworkarea,thepositionandsizeofthepipesonthesurface,logisticsandavailabilityofsurveysvesselandroadaccesstotheworkarea.

Picture2.Signthepositionofthepipeintheground(left)andtheappearanceonthesurfaceofthepipe(Right)




Picture3.SitePlanofSBPsurveySBPsurveyconductedinfour(4)pointlocationascanbeseenintheimageabove.




3.1.2 Equipment

a. NavigationandPositioning 1(one)unitofTrimble5700GPS 1(ane)unitofNotebookandNavigationSoftware(HydroPro)

Picture4.Trimble5700GPS(left)andAntenaGPSTrimble(right)

b. SubBottomProfiling(SBP)Survey 1(one)unitofSyqwestStratabox3510SBPSystem

Picture5.Stratabox10KHzTranducer(left)andStrataboxConsole(right)




2 m

0,95 m

GPS Antenna

1,72 m

SBP Stratabox Transducer Draft : 0,6 m

6,5m

3.1.2.SupportLogistics 1(one)unitofWoodenBoat 1(one)unitofGenerator 1(one)unitofBatteryDCPowerSupply12volt35A

Picture6.SBPSurveyVesselOffset(above)andsurveyvesselused(below)




3.2 ImplementationPhase3.2.1 PositioningSystem

Positioning systemusingTrimble5700GPSmountedon the surveyvessel.PositionvaluesrecordedwiththehelpofsoftwareHydroprov.2.3. Position data Recorded every 2 seconds or about 5 meters.This positioning system refers to a system ofUniversal TransverseMercator (UTM) Zone 48 (Southern Hemisphere) WGS 84 EllipsoidReference.

Picture7.HydroproNavigationSystem(left)andnavigationprocess(right)

3.2.2 SubBottomProfiling(SBP)Survey

SubBottom Profiling Survey (SBP) were performed using anStratabox Syqwest 3510 System integratedwith the Trimble 5700GPSnavigationsystem.Tranducer (sourceandsensor) ismounthingontherightsideofthesurveyvesselwithadraftof0.6mfromsealevel.




Picture8.ProcessofinstallationStrataboxSystem

Picture9.ProcessofrecordingandqualitycontroldataSBP

Theworkingprincipleof this instrument is Stratabox acousticwavepulse issentdowntothesurfacewillbereflectedbackbythe layersofsedimentseabed/riverandwillbereceivebackbythereceiveratthesurface.Wavesrecordedatthesurfacewillprovideanoverviewofgeological structuresandobjects sedimentary stratabeneath theseabedsurface/rivertransversely(imagesection).Sourceoftheacousticwavesworkingatfrequencyof10kHz,withthepenetrationcapabilityofabout20mwithasensitivityofupto6cmthicknessofthelayerdependonthesedimenttype.




Picture10.SubBottomProfiling(SBP)method

3.3 DataProcessing

Dataprocessingstages includedataprocessingand interpretationofpipedepth.

3.3.1 PengolahanDataSubBottomProfiling(SBP)

Prior to interpretation, the SBP data going through the process ofprocessing data prior to obtaining a better seismic image. Theprocessingofdataiscarriedoutincluding:a.Geometry

This stage aims to prepare the data before through the filteringstages so that the raw data would be to have the value of pathlength,thecoordinatesofthetrajectoryandtheactualdata length.b.Filtering

Filteringaimstominimizenoiseandreducediffractioneffects inthedatathatcaninterferewiththeprocessofinterpretation.




c. Muting

Mutingstageprocess istoeliminatethewatercolumnbetweenthesurfaceandthebottomsurfaceoftheriversothatthedatawillbefreeofsurfacenoise.

3.4 DataInterpretation

Afterprocessingthedata,thenextstep isto interpretthedepthofexistingpipelineinthearea.

Toassisttheinterpretation,atthefieldhasbeencarriedoutMarkingthe position of the pipe on the SBP of data based on the positioninformation of the pipe based on secondary data. Secondary datawereusedincludingthepipepositiondatafromtheClients(CADfile)andpipepositionsonlandfrompreliminarysurvey.

Picture11.Secondarydataofpipeposition(Autocad)

Location 1

Location2

Location 3

Location 4




Picture12.MarkingResultsofthepipelinepositiononfieldintheSBPdata

Picture13.InterpretationoftheSBPdataResults.Pipe(redcircle)andanotherobject(yellowcircle)

Amplituderesponseindicatinganobjectbelowtheseabed/riveronthedataofSBP is influencedbyseveralfactors includingthetypeofseabed sediment / river, pipe dimensions and depth of the pipebelowthesurfaceoftheseabed/river.

ForCBLriverandMuaraGembongarea,thesurfaceisdominatedbythickMudsediment, itcausestheseismicwaveenergyabsorbedbythe layersothattheseismicwavesexperiencea lossofenergy fastenough andweakenedwith depth. Location of pipe in this area isestimated to be at a fairly shallow depth (under 5 feet of water

Marking

Marking




surface)sothatthereflectionofseismicwavesfromthepipeunderthe bottom surface of the river indicated by a point or thickamplitudespot.




4. ResultAfter going through the data interpretation of the obtained results asfollows:4.1 Location1Pictureofthelocationcanbeseeninthefollowingdocumentation,

Picture14.AreaLocations1contained3crossingraftAt location1,thereare3raftpathsthatcrosstheCBLriversotheteamhaddifficultypassingropestheCrossingraft.Atlocation1therearetwo(2)trajectoryofSBP,Line1L1andLine1L2.Thepositionofthetrajectorycanbeseeninthefigurebelow,




Picture15.PipepositionandtheLineatLocation1

Line1L1

Picture16.SBPRawdataLine1L1andpipeMarkingonthefield

Picture17.Interpretationresult.Pipe(redcircle)online1L1locatedatadepthof2metersfromthesurfaceoftheriverbed.

1L11L2

Pipe

Marking




Picture18.ZoompipelineAreaanomaliesintheSBPdatathatisdisplayedintheWiggleform

Basedonthepictureabovelookforareasofpipeanomalieshaveamplitudesandperiodsgreaterthanaroundit.

Line1L2


Picture20.Interpretationresult.Pipe(redcircle)online1L2locatedatadepthof1meters

fromthesurfaceoftheriverbed.

Marking





Basedontheresultsof interpretation,fortheanomalousonLIne1L1 isindicated as the pipe is at a depth of 2 meters. As for the Line 1L2anomalyisatadepthof1meter.

4.2 Location2Pictureofthelocation2canbeseeninthefollowingdocumentation,




Picture22.PipesareseenonthesurfaceintheareaofLocation2At location2, thereare3 (three)TrajectoryofSBP,Line2L1,Line2L2and Line 2L3. The third position of the trajectory can be seen in thefigurebelow,

Picture23.PipepositionandSBPLineonLocation2

2L1

2L2

Pipe

2L3

Pipe




Line2L1


Picture25.Interpretationresult.OnLine2L1,pipe1locatedatadepthof0.5mfromtheriverbed,pipe2and4locatedatadepthof2m,pipe3atadepthof4mandpipe5

areclosetothesurfaceoftheriverbed

a).

MarkingMarking




b).

c).

d).




e).

Picture26.ZoompipelineAreaanomaliesintheSBPdatathatisdisplayedintheWiggleformforallpipeonLine2L1.A).Pipe1,b).Pipe2,c)pipe3,d)pipe4

dane).Pipe5

Basedonthepictureabovelookforareasofpipeanomalieshaveamplitudesandperiodsgreaterthansurroundingareas,andtheresultsareasfollows,

Pipe DepthfromRiverbed(meter)pipe1 0.5pipe2 2pipe3 4pipe4 2pipe5 Closetothesurface

Table1.Interpretationresultforlocation2Line2L1




Line2L2


Picture28.Interpretationresult.OnLine2L2,pipe1locatedatadepthof0.5mfromtheriverbed,pipe2and4locatedatadepthof2m,pipe3atadepthof4m

a).

Marking Marking




b).

c).

d).

Picture29.ZoompipelineAreaanomaliesintheSBPdatathatisdisplayedintheWiggleformforallpipeonLine2L1.A).Pipe1,b).Pipe2,c)pipe3,and

d)pipe4




Based on the results of interpretation, for the anomalous location 2pipelinedepthobtainedasfollows,

Pipe DepthfromRiverbed(meter)pipe1 0.5pipe2 2pipe3 4pipe4 2


Line2L3


Picture31.Interpretationresult.OnLine2L3,pipe1locatedatadepthof0.5mfromtheriverbed,pipe2and4locatedatadepthof2m,pipe3atadepthof4mandpipe5

locatedclosetothesurfaceofriverbed

MarkingMarking




a).

b).

c).




d).

e).

Picture32.ZoompipelineAreaanomaliesintheSBPdatathatisdisplayedintheWiggleformforallpipeonLine2L1.A).Pipe1,b).Pipe2,c)pipe3,d)pipe4and

e).Pipe5

Based on the picture above look for areas of pipe anomalies haveamplitudesandperiodsgreater than surroundingareas,and the resultsareasfollows,




Pipe DepthfromRiverbed(meter)pipe1 0.5pipe2 2pipe3 4pipe4 2pipe5 Closetothesurface


4.3 Location3Picture of the location 3 can be seen in the results of the followingdocumentation,

Picture33.AtLocation3therearesignofPertaminapipelinenearaCBLRiver




Atthe location3,thereare3(three)trajectoryofSBP,Line3L1,Line3L2,andLine3L3.Thepositionofthetrajectorycanbeseeninthefigurebelow,

Picture34.PipepositionandtrajectoryonLocation3

Line3L1


3L1

3L3

Pipe

Marking

3L2




Picture36.Interpretationresult.OnLine3L1,pipelocatedatadepthof2mfromtheriverbed


Lintasan3L2


Marking




Picture39.Interpretationresult.Pipe(redcircle)onLine3L2locatedclosetotheriverbed


Line3L3


Marking




Picture42.Interpretationresult.Pipe(redcircle)onLine3L3locatedclosetotheriverbed


Basedontheresultsofinterpretation,forthelocation3,anomalyonLine3L1isindicatedasthepipeisatadepthof2meters.AsfortheLine3L2andLine3L3anomaliesarenearthesurfaceoftheriverbed.4.4 Location4Location 4 description can be seen in the results of the followingdocumentation,




Picture44.Location4areintheseanearMuaraGembong

At location4,thereare3(three)trajectoryofSBP ,Line4L1,Line4L2,and Line 4L3. The position of the trajectory can be seen in the figurebelow,

Picture45PipepositionandthetrajectoryonLocation4

4L1

4L3

Pipe

4L2




Line4L1


Picture47.Interpretationresult.pipe(redcircle)onLine4L1locatedatadepthof2,2mfromtheriverbed


Basedonthepictureabovelookforareasofpipeanomalieshaveamplitudesandperiodsgreaterthanaroundit.

Marking




Line4L2


Picture50.Interpretationresult.pipe(redcircle)onLine4L2locatedatadepthof2mfromtheriverbed


Marking




Line4L3


Picture53.Interpretationresult.pipe(redcircle)onLine4L3locatedatadepthof2mfromtheriverbed


Marking




Based on the interpretation results of location 4 SBP data, AnomalyindicatedasthepipeonLine4L1 isatadepthof2.2meters.AsfortheLine4L2andLine4L3anomalyisatadepthof2mfromtheseafloor.Followingisasummarytableofeachpipedepthforalllocation,

Table1.Listofpipedepthinterpretation




5. Conclusions

1. Thick Mud sediment Type and shallow depth of the pipe causing theindicationsofthepipeline intheformofapointorhighamplitudespot.

2. On Location 1 pipe located at a depth between 12 meters from thesurfaceoftheriverbed.

Forlocation2thereare5pipes,thepipesarelocatednearthesurfaceupto4mfromtheriverbed.Thenatlocation3,thepipeisnearthesurfaceupto2metersfromtheriverbed.For the last locationof the Location4which is in thewatersofMuaraGembong to theoffshoredirection, thepipewasatadepthof2 2.2metersbelowtheseabed.


Documents

Appendix 2. Sub-bottom Profile