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Method Statement Report OSMOSUN 100TM Desalination Plant

Witsand, South Africa

Prepared for

Turnkey Water Solutions

Prepared by

WML Coast (Pty) Ltd

and

Alternative Services Technology (Pty) Ltd

20 July 2018

WMLCoast(Pty)LtdandAlternativeServicesTechnologies(Pty)Ltd i

Quality Management

Project number: 180423

Issue FINALV0

Date 2018/07/20

Preparedby Checkedby Authorisedby

EnriqueJulyan

andDudleyJanekeSpecialists

LaurieBarwell

ManfredKloos

Revision

Date


Revision

Date


WMLCoast(Pty)LtdandAlternativeServicesTechnologies(Pty)Ltd ii

Table of Contents 1 IntroductionandBackground.........................................................................................................3

2 SiteDescription...............................................................................................................................5

3 Somerelevantsitecharacteristics..................................................................................................7

3.1 TidelevelsintheoceanatWitsand.........................................................................................7

3.2 RiverFlooding..........................................................................................................................8

3.3 Geohydrology...........................................................................................................................8

4 ShortsummaryoftheOSMOSUN100process...............................................................................9

5 Sitelayoutoverview......................................................................................................................11

6 MethodStatements......................................................................................................................12

6.1 Methodstatement1.1:IntakeWorks–Option1..................................................................14



6.4 Methodstatement2:Steelintakepipelineacrosssteepslope.............................................26

6.5 Methodstatement3:BuriedHDPEsupplyandeffluentpipelines........................................28

6.6 Methodstatement4:BuildingsandinfrastructurefortheROplant.....................................30

6.7 Methodstatement5:SolarFarmInfrastructure....................................................................32

6.8 Methodstatement6:Steeleffluentpipelineacrosssteepslope..........................................34

6.9 Methodstatement7:Brineoutfallworksalongestuarybank..............................................36

6.10 Methodstatement8:Botanicalaspects..............................................................................38

7 Closure..........................................................................................................................................39

List of Figures Figure1:Typicalappearanceofcurrentnaturalrockshelf (Bokkeveldshale)attheestuary/river’sedge.......................................................................................................................................................6Figure2.Viewofexistingpumpingstationinfrastructure–lookingnorth...........................................6Figure3:Typicalvegetationatlowersectionofsteepriverbank..........................................................7Figure4:Predictedfuture50-yearand100-yearreturnintervalfloodlevels(BreedeRiverFloodlineStudy).....................................................................................................................................................8Figure 5: Vertical sectional sketch of aquifer and groundwater relationship – looking upstream(Steenekamp,2018)..............................................................................................................................9Figure6:Proposedsitelayout.............................................................................................................11

List of Tables Table1:CharacteristictidallevelsatWitsand(SANHO)........................................................................7

180423OSMOSUN100TMDesalinationPlant July2018METHODSTATEMENTREPORT Rev:FINALV0

WMLCoast(Pty)LtdandAlternativeServicesTechnologies(Pty)Ltd 3

1 Introduction and Background

The Hessequa Municipality has created the Hessequa Innovation Helix in collaboration with the

Stellenbosch Good Governance Forum (University of Stellenbosch) to implement innovative

solutions addressing the prevailingwater crisis/shortages in theWestern Cape. Given its pressing

need for water, the Hessequa Municipality has expressed its interest in implementing a pilot

OSMOSUN®plant on the critical coastal area ofWitsand. TheOSMOSUN is a desalination system

whichispoweredbysolarenergy.TheOSMOSUNisaproductofMascaraRenewableWater1.

Mascara RenewableWater have applied for a grant from the French treasury (FASEP innovation

verte).Thegrantwouldfundupto50%ofthepilotproject.Thishasbeendonewiththesupportof

the French Embassy in Pretoria. Approval in principle of the grantwas given on September 15th.

Hessequa Municipality has subsequently applied for the financing of the balance against the

WesternCapeDroughtRelieffundingwhichwassubsequentlyapproved.

TheprojectstakeholdersareshownintheTablebelow:

Name RoleHessequaMunicipality ClientTurnkeyWaterSolutions SolutionProviderAlternativeServicesTechnologies CoordinationoftechnicalspecialistsMascara OSMOSUNdesignersWMLCoast CivilEngineeringConsultantCapeEA-Practitioners EnvironmentalConsultantAnchorEnvironmental EffluentDispersionModelling

WMLCoast (Pty)Ltdwasappointedtodesignthecivil infrastructurecomponents required for the

project.AlternativeServicesTechnologies(Pty)LtdwasappointedtoassistTurnkeyWaterSolutions

withthecoordinationofinputfromthevarioustechnicalspecislists.

This report provides the detail of themethodology for the implemetation of the project. The so-

called Method Statement Report provides more detail on the individual tasks, roles and

responsibilities of the various roleplayers and lists key risks and the associated mitigatory /

managementactionsrequiredtoreducetherisks.

1http://mascara-nt.fr/en/about/#company



Thereportshouldbereadtogetherwiththedesignreport2butcanbeseenasastandalonereport.

It also forms part of the main Environmental Management Programme (EMPr) and the Method

StatementswillbeadoptedaspartoftheapprovaloftheEMPr.

NormallythecontractorshallprovideMethodStatementsforapprovalbytheEnvironmentalControl

Officer (ECO)and theResidentEngineer (RE)prior towork commencingonaspectsof theproject

deemedoridentifiedtobeofgreaterrisktotheenvironmentand/orwhichmaynotbecoveredin

sufficientdetail intheEnvironmentalManagementProgramme(EMPr),whencalledupontodoso

by the RE or ECO. In this instance the project applicant provided sufficient detail in theMethod

Statementstoensurethattheenvironmentalregulatoryauthoritycanmakeaninformeddecisionto

adoptitaspartoftheEMPr.

ItiscrucialthatcarefulthoughtneedstobegiventothedraftingoftheseMethodStatementsinthe

absence of an Environmental Impact Assessment study, which will under normal circumstances

assess all the potential negative environmental impacts during the construction phase of the

proposed development and provide mitigatory measures to minimise the impacts on the

surroundingenvironment.

Onceappointed,thecontractorwillbeheldaccountabletoundertaketheconstructionactivitiesin

accordancewith the pre-approvedmethod statements to ensure duty of care and accountability

duringthemostsensitivephaseoftheproject.

A Method Statement is a “live document” in that modifications are negotiated between the

Contractor and the ECO or project management team, as circumstances unfold. All Method

Statementswill formpartof theEMPrdocumentationandaresubject toall termsandconditions

containedwithintheEMPr.

Note that aMethod Statement is a ‘starting point’ for understanding the nature of the intended

actions to be carried out and allows all parties to review and understand the procedures to be

followedinordertominimiseriskofharmtotheenvironment.

Changesto,andadaptationsof,MethodStatementscanbeimplementedwiththepriorconsentof

allparties.

2DesignReport:OSMOSUN100DesalinationPlant,Witsand,SouthAfrica.WMLCoast(Pty)Ltd.July2018.



AMethodStatementdescribesthescopeoftheintendedworkinastep-by-stepdescriptioninorder

fortheECOandtheREtounderstandtheContractor’sintentions.Thiswillenablethemtoassistin

devisinganymitigationmeasures,whichwouldminimiseenvironmentalimpactduringthesetasks.

For each instance where it is requested that aMethod Statement is to be provided, the format

shouldclearlyindicatethefollowing:

o What-abriefdescriptionoftheworktobeundertaken;

o How-adetaileddescriptionoftheprocessofwork,methodsandmaterials;

o Where-adescription/sketchmapofthelocalityofwork(ifapplicable);

o When - the sequencing of actions with due commencement dates and completion date

estimates;and,

o Who – The person responsible for undertaking the works described in the Method

Statement.

TheabovementionedformatwasusedtopreparethedifferentMethodStatementsincludedinthisreport.

2 Site Description

Thedesalinationplantwill be constructedon a site located to thenorthof the townofWitsand,

Western Cape South Africa. Existing infrastructure at the designated site includes a borehole

pumpingstation(34°24'4.35"S,20°47'16.34"E)whichsupplieswatertothetownreservoiradistance

ofabout2.3kmaway.ThisreservoiristhemainwatersupplyreservoirforWitsand/PortBeaufort.

Theexistinginfrastructureconsistsofthefollowing:

• Aboreholewithboreholepump,approximatedepth200m.Historicyield in theorderof8

l/s,currentyieldintheorderof2l/swithhighManganesecontent

• Generatorandvalveroomfortheboreholepump.

• Associatedpiping (visiblepipingmaterial is steel)–pipediameter in theorderof110mm

outsidediameterOD.

• Theboreholepumpstationandpipelinehaveexistingservitudes.Theboreholeissurrounded

by2farmportionswithdifferentownersascanbeseenonthelocalityplans.

TheexistingboreholesiteissituatedonahillnexttotheBreedeRiverEstuaryatameanheightof+

35mMSL.Thehillslopessteeplytotheriver/estuary.Theriverbankisovergrownwith indigenous



vegetation.Thesitewascomprehensivelysurveyedandthecontourlevels(tomMSL)areshownon

drawingsinthedesignreport.

Portionsofthenaturalterrainareshowninthefollowingimages:

Figure1:Typicalappearanceofcurrentnaturalrockshelf(Bokkeveldshale)attheestuary/river’sedge.

Figure2.Viewofexistingpumpingstationinfrastructure–lookingnorth.



Figure3:Typicalvegetationatlowersectionofsteepriverbank.

3 Some relevant site characteristics

3.1 Tide levels in the ocean at Witsand

Table1:CharacteristictidallevelsatWitsand(SANHO)

Witsand(mCD) Witsand(+mMSL)Levellingdatumcorrection -0.8605 0LAT(LowestAstronomicalTide) 0 -0.8605MLWS(MeanLowWaterSpring) 0.265 -0.5955MLWN(MeanLowWaterNeaps) 0.815 -0.0455ML(MeanLevel) 1.095 0.2345MHWN(MeanHighWaterNeaps) 1.375 0.5145MHWS(MeanHighWaterSprings) 1.94 1.0795HAT(HighestAstronomicalTide) 2.255 1.3945HATIncludingpotentialsealevelrise(+0.5mby2050) 2.755 1.8945HATIncludingpotentialsealevelrise(+1.0mby2100) 3.255 2.39451:100yearrverfloodlevel 6.14 7.0

Notethattheinformationonthesealevelrise(SLR)valuesaretakenfrom(2018)reportsby

the Eden DistrictMunicipality on coastalmanagement lines. The site is located along an



estuary with a normally wide open mouth, thus the tidal levels (and future SLR) are

relevant.Sincethesiteis locatedwithintheestuary,adefaulthazardlevelof+5mMSLis

relevant.However,sincethe1:50yrand1:100yrfloodlineshavebeendetermined,these

areincluded.

3.2 River Flooding

TheBreedeRiverexperiencesperiodical flooding.The intakeandoutfall infrastructureare

designedtowithstandfloodingevents.The50-yearand100-yearfloodlinesoftheriverin

theinterestareaareshownontheFigure4below:

Figure4:Predictedfuture50-yearand100-yearreturnintervalfloodlevels(BreedeRiverFloodlineStudy).

3.3 Geohydrology

The northern riverbank at the location of the proposed river intake consists of exposed

“BokkeveldShale”rock(seeFigure5).



Figure5:Verticalsectionalsketchofaquiferandgroundwaterrelationship–lookingupstream(Steenekamp,2018).

4 Short summary of the OSMOSUN 100 process

The OSMOSUN 100 is powered by solar energy, however, the power supply to the

desalination plant can be augmented by the main power grid and/or an existing diesel

generator on site. The potablewater permeate output of theOSMOSUN100 plant using

solar power only is in the order of 100 m3/day during sunlight times. If it is operated

continuously (day andnight) with the addition of grid power the plant can produce 300

m3/day.

Rawwaterfromtheestuaryisabstractedatamaximumrateof40m3/h.Theintakerateis

scaleable and is a function of the energy available. The intake water is pumped either

directlythroughasandfilterandintotheOSMOSUN100(1pump,nostorage)orpumped

from the river into a reservoir located adjacent to theOSMOSUN 100 and then pumped

throughthesandfilterfromthereservoir(2pumps).

The generated brine (effluent) will be dispersed into the river via an environmentally

compliantdiffuseroutlet.Ifpre-treatmentofthebrineisrequiredabrinestoragetankwill

beerectedadjacenttotheOSMOSUN100plant.



The design of the intake works, the supply pipline, the infrastructure for the Reverse

Osmosis (RO) Plant and solar farm, the permeate delivery component as well as the

effluent management system and discharge pipeline and outfalll works are described in

design report: Preliminary Design Report: OSMOSUN 100 Desalination Plant, Witsand,

SouthAfrica.WMLCoast(Pty)Ltd.July2018.

Thedispersalof thebrine fromtheplantatWitsand isdescribed in thespecialist report:.

LairdMC,WrightAGandClarkBM.2018.NearfieldModellingandAssessmentofImpacts

for the Proposed Reverse Osmosis Plant at the Breede River Estuary, South Africa.

SpecialistReportno.1799/3preparedbyAnchorEnvironmentalConsultants(Pty)Ltdfor

TurnkeyWaterSolutions.Pp71.

Permeatefromtheplantwillbestoredinareservoironsiteandandthenpumpedtothe

municipalreservoir.

The process diagrammes and technical specifications of the OSMOSUN 100 plant are

providedinthedesignreport.

5 Site layout overview

Shown below in figure 6 are the key components for which method statements are

prepared.

Figure6:Proposedsitelayout

Followingthelogicalprocessflow(fromtherawwaterintakeworks,throughtheROplant

to the effluent outfall works), the key to Figure 6 and theMethod Statement tables are

providedinthetablebelow.



Refnumber

Key(Fgure6)

Shortdescription MethodStatementtablenumber

RelevantTechnicalDrawings3

1 IW IntakeWorksonestuarybank.Threeoptionsarepresented

MS1.1;MS1.2;MS1.3 180423-31to-33180423-34180423-35to-38

2 IP Supplypipeline(steelatthesteepslope)

MS2

3 P BuriedHDPEpiplines MS3 4 RO Buildingsand

infrastrustuctureforROplant

MS4 180423-21Ato180423-27A

5 SF SolarFarmandFence MS5 180423-41to--42180423-51A

6 OP Effluentpipeline(Steeldownsteepslope)

MS6

7 OW Outletworksalongestuarybank

MS7

8 BOT Botanicalaspects MS8 -

6 Method Statements

Rawwaterintakeworks:functionalrequirements

Thegeneralrequirementsoftheintakesystemarelistedbelow.

• Provideintakeflowofriverwateratamaximumrateof40m3/h;

• Environmentaldesigncriteriafortheintake,EPAguidelines.Intakevelocity<=

0.15m/s;Smallgridspacingmaynecessitateregularcleaning/maintenance;

• Waterintakeat–1.5mMSLtoallowforrequiredsubmergenceatalltidalwater

levels;

• Intakeassemblymadeofgalvanisedsteeland/orstainlesssteel;

• Pipelinefromintakeassemblyacrosstherock-shelfontheriverbankencasedin

concreteasprotectionduringriverfloods;

• Intakepipelinewillhavenovalvestoreducepossiblemaintenanceimplications;

• Intakeshouldallowforpipelinecleaningusinga‘pigging’technique;

3PreliminaryDesignReport:OSMOSUN100DesalinationPlant,Witsand,SouthAfrica.WMLCoast(Pty)Ltd.July2018.



• Intakeassemblymodularallowingforreplacingandmaintenanceofdiscrete

elementsasrequired;

• Intaketooperateinvaryingriverwaterlevels–notedesalinationplantwilllikelynot

beoperatedinextremefloodsashighsiltcontentofintakewaterwillclogfilter

systemsexcessively.Usagetobedeterminedbyplantoperators.

Threeintakeconfigurationshavebeendeveloped.Eachoneisconsideredtobefeasibleand

achievable.Thechosenoptionwillbefinalisedbasedoncostsandpercievedrobustnessand

easeofmaintenance:

Option1:RiverbankPumphousewithSelf-PrimingPump

Option2:FloatingPontoonIntake

Option3:RiverbankPumpstationwithSubmersiblePump

Method Statements (MS 1.1 toMS 1.3) are provided for each of the three intakeworks

options.



6.1 Method statement 1.1: Intake Works – Option 1

TABLEMS1.1INTAKEWORKSONESTUARYBANK:

OPTION1:PUMPHOUSEANDSELF-PRIMINGPUMP

1. SPECIFIC LOCATION: Refer to the layout on Figure 6, specifically component IW, theIntakeWorks.2.DESCRIPTION:

Thesealedconcretepumphouse (chamber) isbuiltonaconcrete footingboltedonto thenaturalrock.Aself-primingelectricalpumpisinstalledinsidethechamber.Thestructureissealedfromoutside.Accesstostructureisviaasteelhatchwith2doors.Largedoorforthepumpinstallationandmaintenanceandregularhatchforpersonnelaccess.Thekeycharecteristicsofthedesignareshownintheabovefigure.Thepipealongtherock-shelfontheriverbankwillbeencasedinconcreteasshowninthefigurebelow.Theconcreteencasingisanchoredtotherockshelf.Theconcreteencasingisforprotectionagainstfloodevents.



At the end of the intake pipelinewill be a fabricatedwedge-wire intake screenwhich isbolted to the intake pipeline. The intake screen is sized to ensure compliance withenvironmentalguidelines.Theintakeisshownschematicallybelow.

Forthedrypumpinstallationinthechamber,aself-primingpumpisproposed.Self-primingpumpsprimethesuctionlineeachtimetheyarestarted.Self-primingpumpsaregenerallymore reliable thanother (generallyaftermarket) self-primingsystems.Self-primingpumpsaregenerally lessefficient than theequivalentnon-primingpump.A self-primingpump ispreferred for a dry pump installation as there is no requirement for check valves whichcould pose issues in a saline river intake environment with intermittent intake flowrequirementanddailydown-time.Thepumpwillbeconstructedfromcast-ironwithananodeattachedtoalleviatecorrosion.The anodewill be replaced as required. The dry installation of the pump allows for easymaintenanceofthepumpwhenrequired.Theintakesystemisdesignedtofacilitatepipelinepigging(cleaning).Thepumpisinstalledofflineofthemainpipelinealignment,therebyallowingofabypassofthepumphouseviaappropriatevalveactuation.Theendoftheintakeassemblyhasablankflangewhichcanberemovedwhenpiggingthepipeline.Thepigwillbeinstalledintothepipelinejustupstreamoftheintakewaterstoragetank.



The intake assembly is modular and segments can be unbolted to be cleaned and/orreplaced.Moredetailofthedesignisshowninthedesignreport.3.SPECIFICACTIONS:Toconstructthepumphouseasmallsegmentoftheclifffacewillbeexcavatedtoprovidea“cove” inwhich to build the pumphouse, thereby providing additional protection againstflood damage. The intake assembly will be transported to the site via personnel or anexcavator.Anexcavatorwill hold theassembly in-placeduringboltingof theassembly tothepipesegmentprotrudingfromtheconcretepipelineencasing.Developmentfootprint:

Pipelineandintake:14mx0.5m=7m2

Pumpstation:2.9mx3.5m=10.15m2

Requiredexcavationvolume:

Pumpstationcove≈1.5mx3mx3.5mx0.5m=7.8m3

4.TIMING:Aspertheconstructionschedule.

5.SUPERVISORYPARTY:

• Applicant:HessequaLocalAuthority–MunicipalTechnicalDirector

• ManagingAgent/ResidentEngineer–TBC

• ProjectManager–TBC• EnvironmentalControlOfficer–TBC• Marineecologist–Anchor

Environmental• Commercialdivingsupervisor(ifdivers

areused)• SafetyOfficer

6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmustbeappropriatelyqualifiedandworkunder therelevant levelof supervision.EnsuringthisistheECOandcontract’smanager’sresponsibility.Allcontractingstaffshouldhavebeeninductedpriortocommencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipment typically associatedwith the placing of equipment and structures underwater



will be used (if divers are needed).Methods and standards according to the appropriateSABSstandardstobeadheredto.Equipmenttypicallyassociatedwithexcavationandsitepreparationwillbeused.MethodsandstandardsaccordingtotheappropriateSABSstandardstobeadheredto.Access forconstructionvehicles tothesitewillbealongademarcatedpathwayalongtherockshelfillustratedinFigure1.Deepgulleysorholescanbebridgedbytemporarymeans.NarrowconcretestrippathwayscanbecastinselectedareasinconsultationwiththeECO.Thesewillremaininplacetoassistaccessduringmaintenanceoremergencies.7.RISKS:Working underwater is a specialised job(whenneeded).Drillingintotherockfaceandepoxygroutingthe required pipe brackets i.t.o the anchorholes will disperse rock fragments into thewater column. This is a limited and localimpact.

The excavation of the ‘cove’ for thepumphouse will result in an excess ofmaterialbeingproduced.Theriskisthatthismaterialwill landup in theestuary therebysmotheringthemarineorganismsorcausinganartificialunderwaterhazard.Softer material that may wash off theconstruction site should be prevented fromdispersingwithin thewater column beyondtheimmediateconstructionfootprint.

8.PREVENTATIVEMITIGATORYACTION:Only qualified commercial divers and asupervisorshouldbeused(ifrequired).Construction materials should be non-toxicasfaraspossible.Concreteisacceptable.No blasting is foreseen. An excavator,possibly with a ‘hydraulic pecker’configuration will be used (see example inTableMS1.3below).Material excavated from the ‘cove’ shouldbe re-used for backfilling between thechamber and the excavation if possible. AllexcessmaterialshouldberemovedfromthesiteanddisposedofatanappropriatesiteasspecifiedintheEMPr.To minimise any possible negativeenvironmentalimpact,thecontractorhastoensure that concrete is not mixed in theintertidal area and that cement bags areimmediately placed in refuse bins whichneedtobeavailableonsite.A floating geofabric curtain fixed to thebottom with sandbags to be installed inradius of 5 m in the estuary around theconstructionsiteso-astolimitthedespersalof any fine material beyond the site andthusnotpollutingthewaterbody.




TABLEMS1.2INTAKEWORKSONESTUARYBANK:

OPTION2:SUBMERSIBLEPUMPONHINGEDPONTOON

1. SPECIFIC LOCATION: Refer to the layout on Figure 6, specifically component IW, theIntakeWorks.2.DESCRIPTION:

The concept makes use of a submersible (borehole-type) pump installed on a floatingpontoonthatishingedofftherock-shelf.Somekeycharacteristicsare:

• Apipepontoon(diameterintheorderof914mmOD)withpipesleeve(diameterintheorderof610mmOD)formountingofsubmersible(borehole-type)pump;

• Pontoonishingedtoallowmovementwithvaryingwaterlevels;• Flexiblepipingisusedatthehingelocation;• Hingesarecastintoconcreteanchorsontherockshelf;• PipingtoOSMOSUN100plantaswithOption1–steelpipecastintoconcretewhich

isanchoredtorockshelf;• Entirepontoonunitisprefabricatedandassembledonsite,placedintoposition

usinganexcavatororsimilarliftingequipment;• Structurewillbedesignedtohandlefloodevents–possiblyalsoincorporate

anchoringsystemtostrapthepontoonifalargefloodisexpected;



Thekeycharacteristicsofthedesignareshowninthefigureabove.AsinOption1,thepipealongtherock-shelfontheriverbankwillbeencasedinconcrete.Thepipesleeveintowhichthepumpisdroppedwillhaveanintakescreen(notshownondrawing)tolimitingressofmarinelifeordebrisandtocomplywithenvironmentalguidelines.Allowanceformechanismstoassistinremovingthepumpandcleaningtheintakescreen.Atthebaseoftheabstractionpontoonwillbeafabricatedwedge-wireintakescreenwhichis bolted to the pontoon. The intake screen is sized to ensure compliance withenvironmentalguidelines.AsubmersibleboreholepumpwillbehousedinsidetheabstractionpontoonasindicatedintheFigures.Thepumpwillbeconstructedfromcorrosionresistantmaterial.Thepumpwillweighintheorderof80kg.Thepumpiscompletelysubmergedinwaterduringoperation.For maintenance the intake screen will be removed. After removal the screen can bereplacedwith a spare clean intake screen. Thepump canbe liftedout of the abstractionpontoonformaintenance.Moredetailofthedesignisshowninthedesignreport.3.SPECIFICACTIONS:AsinOption1,thepipealongtherock-shelfontheriverbankwillbeencasedinconcreteasshown in the figure below. The concrete encasing is anchored to the rock shelf. Theconcreteencasingisforprotectionagainstfloodevents.

Prior to installationof the floatingpontoon intake, twoconcreteanchors for thepontoonhingepointswillbeconstructedontherockshelf.ThedetailisshownonDrawing180423-34.Theconcreteanchorswillbecastdirectlyinpositionandfixedtotherockbymeansofnon-toxicchemicalanchors.



The entire pontoon assembly is pre-fabricated in aworkshop. Themodular elements arethentruckedtosite.Thepontoonelementswillberemovedfromthetruckandplaced inthewaterbymeansofanexcavatoranda lifting slingarrangementora small crane.Theassembledfloatingpontoonwillbemovedtotheinstallationlocation.Thepontoonwillbecontrolledwithpersonnelandropesfromtheriverbank.Developmentfootprint:

Pipeline:12mx0.5m=6m2

Pontoonanchors:2m2

Floatingpontoon:4mx3m=12m2

Requiredexcavationvolume:zero4.TIMING:Aspertheconstructionschedule.

5.SUPERVISORYPARTY:



• ProjectManager–TBC• EnvironmentalControlOfficer–TBC• SafetyOfficer

6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmust be appropriately qualified. All contracting staff should have been inductedpriortocommencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipmenttypicallyassociatedwiththeliftingandplacingofequipmentandstructureswillbeused.Forexampleatrackedexcavatorcanbeusedtoliftandholdthepontoonstructureinpositiontoenable thehingepins tobesecured.Once floating thepipesandelectricitysupply can be connected. Methods and standards according to the appropriate SABSstandardstobeadheredto.Equipment typically associated with drilling the rock anchors and casting the concreteencasement over the steel pipe will be used. Methods and standards according to theappropriateSABSstandardstobeadheredto.Access forconstructionvehicles tothesitewillbealongademarcatedpathwayalongtherockshelfillustratedinFigure1.Deepgulleysorholescanbebridgedbytemporarymeans.NarrowconcretestrippathwayscanbecastinselectedareasinconsultationwiththeECO.



Thesewillremaininplacetoassistaccessduringmaintenanceoremergencies.7.RISKS:Drillingintotherockfaceandepoxygroutingthe concrete encasement units into theanchor holes could disperse rock fragmentsintothewatercolumn.Theimpactislimitedandlocal.Softer material, such as cement water thatmaywashofftheconstructionsiteshouldbeprevented fromdispersingwithin thewatercolumnbeyond the immediate constructionfootprint.Lifting and placing the pontoon structureclose to water is a potential health andsafetyhazard.

8.PREVENTATIVEMITIGATORYACTION:Ageofabric(e.gBidimTM)wrappedaroundatemporarysandbag‘berm’ontherock-shelfenclosing the construction site will preventcementwaterandsuspendedmaterial fromwashingintotheestuary.A floating geofabric curtain (e.g BidimTM)fixedtofloatsatthewatersurfaceandfixedtothebottomwithsandbagstobeinstalledin radius of 5m in the estuary around theconstructionsiteso-astolimitthedespersalofanyfinematerialbeyondthesite.To minimise any possible negativeenvironmentalimpact,thecontractorhastoensure that concrete is not mixed in theintertidal area and that cement bags areimmediately placed in refuse bins whichneedtobeavailableonsite.All labourers involved with the pontoonliftingandinstallationprocessshouldbeableto swim and should wear life jackets at alltimes. All appropriate Personal ProtectiveEquipment (PPE) and Personal ProtectiveClothing(PPC)shouldbeusedatalltimes.




TABLEMS1.3INTAKEWORKSONESTUARYBANK:OPTION3:RIVERBANKPUMPSTATION

WITHSUBMERSIBLEPUMPONRAILTRACK1. SPECIFIC LOCATION: Refer to the layout on Figure 6, specifically component IW, theIntakeworks.2.DESCRIPTION:

Somekeycharacteristicsofthisoptionareshowninthefigureaboveandinclude:

• Boreholepumpismountedtotrolleytypearrangementtoallowforremoval–incorporatedliftingpointstowhichablockandtackleormanualwinchcanbeattached;

• Thetrolleysliderhasloosetolerancestofacilitateremoval;• PipingtotheOSMOSUN100plantissimilartoOptions1&2–steelpipecastinto

concretewhichisanchoredtotherockshelf;• Steelchannelswillbeusedastherailsystemfortheremovalofthepumpandits

screen(so-calledtrolleyassembly);• Flexiblepipingwillbeusedatthebendtoallowforeasierremovalofthesystemfor

maintenance.The trolley has wheels to allow for extraction of the trolley and pump assembly. Formaintenanceor in caseof an imminent large flood, theassembly canbe removedat lowtidewithawinchingarrangement(liftinghooksareprovided).Theintakescreencanthenbecleaned manually. The material removed from the screen should be discarded in anenvironmentally appropriatemanner. For pumpmaintenance the pump can be detachedfromthetrolleyviaaboltingarrangement.



Moredetailofthedesignisshowninthedesignreport.3.SPECIFICACTIONS:AsinOption1,thepipealongtherock-shelfontheriverbankwillbeencasedinconcreteasshown in the figure below. The concrete encasing is anchored to the rock shelf. Theconcreteencasingisforprotectionagainstfloodevents.

Anexcavatorwithhydraulicpeckerwillbeusedtocreateatrenchintherockfaceatlowspringtideoveranumberofdays;Theintakeassemblywillbeplacedintothetrench.Anexampleofthetrenchingequipmentrequiredcanbeseeninthefigurebelow.

Hydraulicpeckerforrockexcavation(example).

Theprefabricatedgalvanisedsteelrailassembly(Drawing180423-37inthedesignreport)willbebroughttositeonatruckandplacedintopositionusinganexcavatoradaptedforlifting(seeexamplebelow).Labourerswilluseropestoguidetheassemblyintopositionin



theexcavatedtrenchandontherockshelf.Theassemblywillbeboltedintotherocksurfacemakinguseofnon-toxicchemicalanchors.Thisworkwillbedonebycommercialdivers.

Exampleofaliftingarrangementonanexcavator.

Developmentfootprint:

Pipeline:8mx0.75m=6m2

Trolleyassembly:13mx1.1m=14.3m2Requiredexcavationvolume:

Rocktrenchexcavation:13mx1.1mx0.6m=7.9m3A3mwideblanket/netsecuredbysandbagsandplacedontherockslopeandestuarybottomforadistanceof3mpasttheendoftheexcavatedtrenchpriortocommencingtheuseof thehydraulicpecker. This is tocollectandremovethedebris.A floatinggeofabriccurtainfixedtothebottomwithsandbagstobeinstalledinaradiusof5mintheestuaryaround theconstruction site so-as to limit thedespersalofany finematerial beyond thesite.4.TIMING:Aspertheconstructionschedule.

5.SUPERVISORYPARTY:



• ProjectManager–TBC• EnvironmentalControlOfficer–TBC• Marineecologist–Anchor



Environmental• SafetyOfficer

6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staff must be appropriately qualified and work under the supervision of a qualifiedcommercial diver. Ensuring this is the ECO and contract’s manager’s responsibility. Allcontractingstaffshouldhavebeeninductedpriortocommencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipmenttypicallyassociatedwiththeliftingandplacingofequipmentandstructuresneartoandunderwaterwillbeused.Forexampleatrackedexcavatorcanbeusedtoliftandholdtherailassemblystructureinpositiontoenabletheboltstobesecured.MethodsandstandardsaccordingtotheappropriateSABSstandardstobeadheredto.Access forconstructionvehicles tothesitewillbealongademarcatedpathwayalongtherockshelfillustratedinFigure1.Deepgulleysorholescanbebridgedbytemporarymeans.NarrowconcretestrippathwayscanbecastinselectedareasinconsultationwiththeECO.Thesewillremaininplacetoassistaccessduringmaintenanceoremergencies.7.RISKS:Drillingintotherockfaceandepoxygroutingthe concrete encasement units into theanchor holes could disperse rock fragmentsintothewatercolumn.Theimpactislimitedandlocal.Softer material, such as cement water thatmaywashofftheconstructionsiteshouldbeprevented fromdispersingwithin thewatercolumnbeyond the immediate constructionfootprint.Lifting and placing the steel rail structureinto the underwater trench will requirelabourers to be positioned close to water.Thisisapotentialhazard.

8.PREVENTATIVEMITIGATORYACTION:Ageofabric(e.gBidimTM)wrappedaroundatemporarysandbag‘berm’ontherock-shelfenclosing the construction site will preventcementwaterandsuspendedmaterial fromwashingintotheestuary.A floating geofabric curtain (e.g BidimTM)fixedtofloatsatthewatersurfaceandfixedtothebottomwithsandbagstobeinstalledin radius of 5m in the estuary around theconstructionsiteso-astolimitthedespersalofanyfinematerialbeyondthesite.To minimise any possible negativeenvironmentalimpact,thecontractorhastoensure that concrete is not mixed in theintertidal area and that cement bags areimmediately placed in refuse bins whichneedtobeavailableonsite.All labourers involved with the close-to-wateractivitiesneedtobeabletoswimandshouldbeissuedwithlife jacketsandsafetyharnesses during the lifting and installation



process.AllPPEandPPCshouldbeadheredto.

6.4 Method statement 2: Steel intake pipeline across steep slope

TABLEMS2 INSTALLATIONOFTHESTEELINTAKESUPPLYPIPELINEATTHESTEEPSLOPE

1.SPECIFICLOCATION:RefertothelayoutonFigure6,specificallycomponentIP,theIntakePipeline.2.DESCRIPTION:Theidentifiedpipelineroutegoesalongasteepslopeintheareafromtheintakeworksattheestuaryup to the relatively flat slopedirectly to thewestof theROplant site. In thisareathegalvanisedsteelpipe(114mmOD)willbeplacedalongaseriesofraisedbracketsfixed to the natural ground or rock. The pipeline alignments can be seen on the layoutdrawing(IndicatedasIPonFigure6).3.SPECIFICACTIONS:Thesteelintakepipelinethatcrossesthesteepriverbankismountedtoaholdingbracketona raised pedestalwhich is driven into the natural ground / rock along the pipeline routefromtheintakeworksatthewater’sedgeuptotheflatterslopeatthetopofthehillwherethepipematerialchangestoHigh-densitypolyethylene(HDPE)andisburiedasdescribedinTableMS3.

Thepipelinealignmentwillbeclearedofvegetationtoallowtheinstallationofthepipeline.Asthepipelinerunsonthesurfacetheamountofvegetationdisturbancewillbeminimal.The pipeline pedestals will be driven into the existing ground as required. Where thesubstrateishardrock,arockdrillwillbeusedandthemetalsupportsgroutedinusinganappropriate adhesive suchas a cement/sandmixor epoxy.Alternatively a small concreteplinthwillbeconstructedtosupportthepipeline.Thesteelpipelinewillbesecuredtothepedestalbyabracket.



Developmentfootprint:80mx0.3m=24m2Requiredexcavationvolume: zero.Material removedby the rockdrill,wherenecessary, isminimal.4.TIMING:AspertheconstructionscheduleandpostActivityAintheBotanicalMethodStatement.

5.SUPERVISORYPARTY:

• Applicant: Hessequa Local Authority –MunicipalTechnicalDirector

• Managing Agent / Resident Engineer –TBC

• ProjectManager–TBC• EnvironmentalControlOfficer–TBC• Botanist–TBC

6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmust be appropriately qualified andwork under the supervision of the ECO andcontract’smanager.All contracting staff shouldhavebeen inductedprior to commencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipmenttypicallyassociatedwiththeclearingofanareaalongthepipelinerouteandtheinstallation of the pipelines will be used. Methods and standards according to theappropriateSABSstandardstobeadheredto.7.RISKS:Destructionordamageofimportantand/orendangered vegatation beyond the directfootprintoftheconstructionactivities.

8.PREVENTATIVEMITIGATORYACTION:Contruction footprint area, eg the pipelineroute and labour access, to be physicallydemarcated and activities strictly restrictedtowithinthearearequiredforconstruction.



6.5 Method statement 3: Buried HDPE supply and effluent pipelines

TABLEMS3 INSTALLATIONOFTHEBURIEDHDPESUPPLYANDEFFLUENTPIPELINES

1.SPECIFICLOCATION:RefertothelayoutonFigure6,specificallycomponentP,theburiedpipelines.2.DESCRIPTION:Theidentifiedpipelineroutegoesalongarelativelyflatslopeintheareaimmediatelytothewestof theROPlantprecint. In thisareaboththeHDPE intakeandeffluentpipelinesareburied in the same trench. The pipeline alignments can be seen on the layout drawing(IndicatedasPonFigure6).TheintakepipelinehasanODof110mm,andthatofthebrineeffluenthasa100mmOD3.SPECIFICACTIONS:Atrenchwillbeexcavatedusingamechanicalexcavatorandthepipelinesburiedalongsidewithinthetrench.Typicaltrenchdetailsareshownonthefigurebelow.Thespecificdesigndetailsareprovidedinthedesignreport.

Developmentfootprint:Buriedpipelinesegment:120mx0.3m=36m2forasinglepipeand60m2fortheareawherethetwopipelinesareplacedsidebysideinasingletrench.Avolumeofbeddingsand(approximately5m3)willbebroughtinforthepipelines.Requiredexcavationvolume:Thetotalvolumeofsoiltobeexcavatedforthetrenchisintheorderof18m3to30m3.Nettexcavationvolumeiszeroasexcavatedsoilwillbeplacedbackintothetrench.Storm water management and rehabilitation of the cleared area will be done to thespecificationsprovidedbytheBotanist.



4.TIMING:AspertheconstructionscheduleandpostActivityAintheBotanicalMethodStatement.

5.SUPERVISORYPARTY:




6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmust be appropriately qualified andwork under the supervision of the ECO andcontract’smanager.All contracting staff shouldhavebeen inductedprior to commencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipment typically associated with the digging of a trench and the installation of thepipelineswillbeused.MethodsandstandardsaccordingtotheappropriateSABSstandardstobeadheredto.7.RISKS:Destructionordamageof importantand/or endangered vegatation beyond thedirect footprint of the constructionactivities.Soil erosion due to stormwater and / orwind within or adjacent to the areas ofconstruction.

8.PREVENTATIVEMITIGATORYACTION:Contruction footprint area, eg the pipelineroutesand labourand/orvehicleaccess, tobe physically demarcated and activitiesstrictlyrestrictedtowithinthearearequiredforconstruction.Storm water and wind erosion controlmanagement, eg contouring and speedyrehabilitationofdisturbedareas.



6.6 Method statement 4: Buildings and infrastructure for the RO plant

TABLEMS4 BUILDINGSANDINFRASTRUCTUREFORROPLANT

1. SPECIFIC LOCATION: Refer to the layout on Figure 6, specifically component RO, thereverseosmosisplant.2.DESCRIPTION:A.DesalinationbuildingThe construction of a building in which the desalination technologies is required. Thecharacteristicsofthebuildingareasfollows:

• BrickbuildingwithNUTECtyperoof• Overalldimension6mx14m(84m2)• Accesstobuildingvialargerollerdoorandsecondarypersonaldoor(fireexit)

Thebuildingaccommodatesthefollowing:

• Intakewaterpre-treatment(sandfilter)• OSMOSUN100desalinationsystem• Watertreatment(remineralisation)• Storagearea• Electricalcontrolsystems

Thespecificdesigndetailsandtherelevantdrawingsareprovidedinthedesignreport.B.StoragetanksUp to three storage tankswill be installedon concretebases adjacent to theOSMOSUN.PlastictankssuchastheRototankorJoJotankareproposed.

• Intake seawater storage, 40m3 is required if Option 1 for the raw waterintakeworksisconstructed.

• Permeatestoragetank,10m3Thespecificationsofthetanksareprovidedinthedesignreport.C:ACCESSROADAccesstothenewROplantandSolarFarmwillbeviatheexistingroadinfrastructure.3.SPECIFICACTIONS:A: Sitewill be cleared and grubbed. Thereafter building foundations dug. Building to be



constructedwithbricksandmortar.Aftercompletionofwallsrooftrusseswillbeerectedonthesupportwallsandtherooftilesplaced.Thetechnicaldesignspecificationareprovidedinthe design report. All activities associated with the installation of the building andinfrastructureshouldadheretoSABSspecifiedconstructionmethodsandstandards.Developmentfootprint:Overalldimension6mx14m(84m2)Excavationvolume:Foundationexcavationvolume:10m3B: The plastic tanks are pre-fabricated andwill be delivered to site by truck. The plastictankswillbeplacedonconcreteplinthstructures(bases).Theplinthsizewillvarydependingonthetankdiameterandisspecifiedinthedesignreport.Theerectionsitewillbecleanedand levelledprior tocastingofconcreteadhering toSABSspecifiedconstructionmethodsandstandards.Developmentfootprint:

Permeatetank:2.5mx2.5m=6.25m2Intakestoragetank(optional):5mx5m=25m2

Requiredexcavationvolume:zeroC:Theuseofnoheavyorspecialconstructionvehiclesandequipment(whencomparedtotypicalfarmingrelatedvehicles–lorries,tractors,etc.)areforeseen.4.TIMING:A&B:AspertheconstructionscheduleandpostActivityAintheBotanicalMethodStatement.

5.SUPERVISORYPARTY:A&B:• Applicant: Hessequa Local Authority –

MunicipalTechnicalDirector• Managing Agent / Resident Engineer –

TBC• ProjectManager–TBC• EnvironmentalControlOfficer–TBC• Botanist–TBC

6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmust be appropriately qualified andwork under the supervision of the ECO andcontract’smanager.All contracting staff shouldhavebeen inductedprior to commencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipmenttypicallyassociatedwiththeconstructionofabrickbuildingandconcreteworkwillbeused.



7.RISKS:Environmental sensitivities relate merely tothe access to, the cleaning of the site andthe construction of buildings and concreteplinths.Careshouldbetakennottospillanycementonconcreteonthebaresoil.Wind-blowndust fromthesiteand/or theaccess road could impact on adjacentfarmland during and post constructionactivities. Uncontrolled rubbish and litterfrom the construction site could impact onadjacentpropertiesandtheestuary.

8.PREVENTATIVEMITIGATORYACTION:To minimise any possible negativeenvironmentalimpact,thecontractorhastoensure that concrete is not mixed on baresoil and that cement bags are immediatelyplaced in refuse bins which need to beavailableonsite.Housekeeping rules contained in the EMPrshouldbeadheredto.Specificnoticeshouldbe taken of limited rubbish and litter beingblownaround.

6.7 Method statement 5: Solar Farm Infrastructure

TABLEMS5 INSTALLATIONOFTHESOLARFARMINFRASTRUCTURE

1.SPECIFICLOCATION:RefertothelayoutonFigure6,specificallycomponentSF,theSolarFarm.2.DESCRIPTION:A solar farmwith power generation of 72.3 kWpwill be constructed on a new servitudeadjacent to the existing servitude. This solar farm will be connected to the electricalinfrastructureasisrequired.Thelayoutofthesolarfarmisindicatedonthelayoutdrawings(Figure6).Theareawhichisrequiredforthesolarpanelsis51mx25m=1250m2.Thesolarpanelswillbemountedtoasteelframestructure.Theframewillhavepostswhichare anchored into pre-augered holes my means of mass concrete. The inclination andspacingofthepanelsistobeconfirmedbysolarsupplieranddesigners.Anapproriatesecurityfencewillbeinstalledfollowingthefencespecification.Thetechncialspecificationsandlayoutdetailsareprovidedinthedesignreport.3.SPECIFICACTIONS:Thesolarpanels,supportinginfrastructureandelectricalcomponentswillbeprefabricatedandbroughttositeviatransportvehicles.Thevariouscomponentswillbedeliveredaspertherequiredinstallationschedule.Theexistingvegetationatthesolarfarmsitewillbeleftundisturbedtolimitdustgeneration



which isdetrimentaltosolarpanelperformanceand increasesmaintenance.Holeswillbecreatedwithanaugermachine.ThesupportcolumnswillthenbeplacedinsidetheholeandthencastintoplacewithmassconcreteaspertherequireddesignspecificationandtoSABSmethodsandstandards.Developmentfootprint:153m2

Excavationvolume(holes):30m34.TIMING:AspertheconstructionscheduleandpostActivityAintheBotanicalMethodStatement.

5.SUPERVISORYPARTY:




6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmust be appropriately qualified andwork under the supervision of the ECO andcontract’smanager.All contracting staff shouldhavebeen inductedprior to commencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Theinstallationofthesolarpanelsandassociatedelectricalequipmentwillbeundertakenbythespecialistconstractor.Equipment typically associated with the installation of the specialist structures, raisedfootingsandinstallationofelectricalcablingandrelatedinfrastructure.7.RISKS:Environmental sensitivities relate merely tothe access to, the cleaning of the site andinstallationof the supporting columns.Careshould be taken not to spill any cement orconcreteonthebaresoil.Wind-blowndust fromthesiteand/or theaccess road could impact on adjacentfarmland during and post constructionactivities. Rehabilitation of disturbed areasshouldcommenceasapundersupervisionoftheECOandBotanist.

8.PREVENTATIVEMITIGATORYACTION:To minimise any possible negativeenvironmentalimpact,thecontractorhastoensure that concrete is not mixed on baresoil and that cement bags are immediatelyplaced in clearly marked refuse bins whichneedtobeavailableonsite.Housekeeping rules contained in the EMPrshouldbeadheredto.Specificnoticeshouldbe taken of limited rubbish and litter beingblownaround.



Uncontrolled rubbish and litter from theconstruction site could impact on adjacentpropertiesandtheestuary.Insufficientablutionfacilities

Make sure that sufficient ablution facilitiesare available to construction staff, normallyonetoiletper15people.

6.8 Method statement 6: Steel effluent pipeline across steep slope

TABLEMS6 INSTALLATIONOFTHESTEELEFFLUENTPIPELINEACROSSTHESTEEPSLOPE

1. SPECIFIC LOCATION: Refer to the layout on Figure 6, specifically component OP, theOutfallPipeline.2.DESCRIPTION:The identifiedpipeline route goesdowna steep slope in the area from the relatively flatslopedirectlytothewestoftheROPlantsiteuptotheoutletworksintheestuary.Inthisareathegalvanisedsteelpipe(OD90mm)willbeplacedalongaseriesofraisedbracketsfixed to the natural ground or rock. The pipeline alignments can be seen on the layoutdrawing(IndicatedasOPonFigure6).3.SPECIFICACTIONS:Thesteeleffluentpipelinethatcrossesthesteepriverbankismountedtoaholdingbracketonaraisedpedestalwhichisdrivenintothenaturalground/rockalongthepipelineroutefromtheflatterslopeatthetopofthehillwherethepipematerialchangesfromHDPEinatrenchburiedasdescribedinTableMS3totheoutletworksatthewater’sedge(MS7).Thepipelinealignmentwillbeclearedofvegetationtoallowtheinstallationofthepipeline.Asthepipelinerunsonthesurfacetheamountofvegetationdisturbancewillbeminimal.The pipeline pedestals will be driven into the existing ground as required. Where thesubstrateishardrock,arockdrillwillbeusedandthemetalsupportsgroutedinusinganappropriate adhesive such as a cement/sand mix or epoxy. Alternatively small concreteplinthwillbeusedtosupportthepipeline.Thesteelpipelinewillbesecuredtothepedestalbyabracket.Developmentfootprint:80mx0.3m=24m2Required excavation volume: zero.Material removedby the rockdrill wherenecessary isminimal.



4.TIMING:AspertheconstructionscheduleandpostActivityAintheBotanicalMethodStatement.

5.SUPERVISORYPARTY:




6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmust be appropriately qualified andwork under the supervision of the ECO andcontract’smanager.All contracting staff shouldhavebeen inductedprior to commencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipmenttypicallyassociatedwiththeclearingofanareaalongthepipelinerouteandtheinstallation of the pipelines will be used. Methods and standards according to theappropriateSABSstandardstobeadheredto.7.RISKS:Destructionordamageofimportantand/orendangered vegatation beyond the directfootprintoftheconstructionactivities.

8.PREVENTATIVEMITIGATORYACTION:Contruction footprint area, eg the pipelineroute and labour access, to be physicallydemarcated and activities strictly restrictedtowithinthearearequiredforconstruction.



6.9 Method statement 7: Brine outfall works along estuary bank

TABLEMS7 CONSTRUCTIONOFTHEBRINEOUTFALLWORKSALONGESTUARYBANK

1. SPECIFIC LOCATION: Refer to the layout on Figure 6, specifically component OW, theOutfallWorks.2.DESCRIPTION:Thebrinecreatedbythedesalinationprocesswillbedischargedbackintotheriver/estuary.Toensureminimalnegativeenvironmentalimpactthedischargeisjettedthroughadiffuserport(jetnozzle)withinternaldiameterof100mmtoenablerapiddilution.Theso-calledBankDischargelocationontherockshelfupstreamoftheintakestructurewasshowntobethepreferedlocationbytheEffuentModellingstudy(Laird et al. 2018).Thesitecharacteristicsinclude:

• Accessviaaroutealongtheestuarybanksharedwiththatoftheintakeworks;• solidanchoringoftheoutfallinfrastructuretothenaturalrockfacethereby

mitigatingtheflooddamagerisk;• theabilityforeasyinspectionandmaintenanceoftheoutfallstructure;and• asufficient water depth to enable sufficient jet mixing and subsequent

dispersion.

TheoutfallpointisshowninFigure6(OW)andisbasedoneaseofconstructionandtominimisedamagetothelocalenvironment.3.SPECIFICACTIONS:Ifthetheoutfallpipelineisboltedtotherockshelfattheestuarywaterside,commercialdiverswillbe needed. The diffuserwill be a structural elementwhich is connected to the concrete pipelineencasingviaaboltedinterface.Thepipealongtherock-shelfontheriverbankwillbeencased inconcreteasshown inthe figurebelow.Theconcreteencasingisanchoredtotherockshelf.Theconcreteencasingisforprotectionagainstfloodevents.



Thedesigndetailisprovidedinthedesignreport.Developmentfootprint:

Pipelineandoutletassembly:14mx0.5m=7m2

Requiredexcavationvolume:none4.TIMING:Aspertheconstructionschedule.

5.SUPERVISORYPARTY:



• ProjectManager–TBC• EnvironmentalControlOfficer–TBC• Commercial Diver and Supervisor if

divingisrequired.• SafetyOfficer

6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staff must be appropriately qualified and work under the supervision of a qualifiedcommercial diver. Ensuring this is the ECO and contract’s manager’s responsibility. Allcontractingstaffshouldhavebeeninductedpriortocommencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipment typically associatedwith the placing of equipment and structures underwaterwill be used.Methods and standards according to the appropriate SABS standards to beadheredto.Access forconstructionvehicles tothesitewillbealongademarcatedpathwayalongtherockshelfillustratedinFigure1.Deepgulleysorholescanbebridgedbytemporarymeans.NarrowconcretestrippathwayscanbecastinselectedareasinconsultationwiththeECO.Thesewillremaininplacetoassistaccessduringmaintenanceoremergencies.7.RISKS:Drillingintotherockfaceandepoxygroutingthe required pipe brackets ito the anchorholes will disperse rock fragments into thewater column. This is a limited and localimpacthowever.Lifting and placing the outfall structure in

8.PREVENTATIVEMITIGATORYACTION:Only qualified commercial divers and asupervisor should be used if under waterworkisrequired.All labourers involved with the lifting andinstallation process of the outfall structureshouldbeabletoswimandshouldwearlife



andclosetowaterisapotentialhazard

jacketsatalltimes.AppropriatePPEandPPCneedtobeadheredto.

6.10 Method statement 8: Botanical aspects

TABLEMS8 BOTANICALASPECTS:SEARCHANDRESCUEANDREHABILITATION

1.SPECIFICLOCATION:RefertocomponentsIP,P,RO,SFandOPshownonFigure62.DISCRIPTION:TheestablishmentofthenewROplantinfrastructurewillrequirethedisturbanceofareasasindicatedintheotherMStables.Thisactivitywilltakeplaceonallthesitesidentifiedforworks on the development precinct. These are (1) the pipeline routes – both intake andoutfalllines,andwheretheyaretogether;(2)thepositionofthebuildingsandtanksonsite;and(3)theareawherethesolarfarmistobeestablished.3.SPECIFICACTIONS:

A: Search andRescueof indigenous, vulnerable or critically endangered specieswithin

thedesignatedworkareas.(Figure6).Rescuedplantstobeplacedinsuitablenurseryarea.

B: The removal and storage in bulk of topsoil identified as containing seedbank orindividualplantsforlateruseintherehabilitationandlandscapingofidentifiedzones.

C:Thepreventionoferosionon someof theseareas thatwouldbeclearedwithin thedesignatedworkingareas.

D:Rehabilitationofsomeoftheworkareas,postconstruction.E:Maintenanceofstabilisedareas,postconstruction,duringtheoperationalphaseofthe

project.4.TIMING:

A:Priortothecommencementofany

works;B:Duringtheinitialexcavationsandor

otherworks;C:Duringongoingconstructionworks;D:Postconstruction;E:Postconstructionandduring

operationalphase.

5.SUPERVISORYPARTY:A: Applicant: Hessequa Local Authority –

MunicipalTechnicalDirectorB:Managing Agent / Resident Engineer –

TBCC:ProjectManager–TBCD:EnvironmentalControlOfficer–TBCE:Botanist–TBC



6.STAFF,PLANTANDEQUIPMENTTOBEUSED:All staffmust be appropriately qualified andwork under the supervision of the ECO andcontract’smanager.All contracting staff shouldhavebeen inductedprior to commencingwithanyworksonsite.AcopyoftheEMPrshouldbeavailableintheSiteOffice.Equipmenttypicallyassociatedwiththesearchandrescueofplantsandtherehabilitationofaconstructionsitewillbeused.7.RISKS:1. Destruction or damage of important

and/orendangeredvegatationbeyondthedirect footprint of the constructionactivities.

2.Soilerosionduetostormwaterand/orwindwithinoradjacenttotheareasofconstruction.

8.PREVENTATIVEMITIGATORYACTION:1. Contruction footprint area, eg the

pipeline routes and labour and/orvehicle access, to be physicallydemarcated and activities strictlyrestricted to within the area requiredforconstruction.

2. Stormwater andwind erosion controlmanagement, eg contouring andspeedy rehabilitation of disturbedareas.

7 Closure

Thisreportcontainsthedifferentmethodstatementswhichwillbeapprovedaspartofthe

maindocumentationoftheEnvironmentalManagementProgramme(EMPr).Itprovidesan

opportunity to properly understand each of the tasks to be undertaken to properly

implement the Witsand OSMOSUN 100 Desalination Project, planning for any potential

negativeimpactsonthenaturalenvironmentandmitigatingagainstit.Thisreportaimsto:

ü summarisetheinfrastructurecomponentsofthedesign;

ü providesadescriptionofthevarioustaskstobeundertaken;

ü providesanunderstandingoftheprocessesandmaterialtobeused;

ü providesabreakdownofthemethodofconstructionoftheseelements;

ü providesalocationoftheworkstobeundertakenviaasketchplanormap

ü providesanunderstandingofthesequencingoftasks,andfinallyit



ü providesanunderstandingofthepeoplethatwouldmanageeachcomponentofthe

taskstoensureresponsibilityandaccountability.

The construction methodology, development footprint and excavation volume of each

componentarebrieflydescribedintheconstructionmethodologysectionofeachrelevant

component.

Insummary,webelievethattheMethodStatementsprovidedinthisreportshouldsatisfy

therequirementsoftheenvironmentalregulatoryauthority,DepartmentofEnvironmental

AffairsandDevelopmentPlanning.

method statement report - cape eaprac witsand... · a method statement describes the scope of the...

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