Project Management Plan Dreddging

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POC Maintenance Dredging Appli cation | January 2014

Attachment D.3

Details of the Loading Operations incl.Dredging Method Statement, Total Loading

Quantities & Water Injection Dredging Tracer

Study by Van Oord (July 2012)Forinspe

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P ro je c t Ma n a g e me n t P lan

Project: Cork Maintenance Dredging Contract Page: 1 of 22

Project no 20.3432 Revision date: 12-Dec-2013

Client Port of Cork Reference: GOO

This document remains intellectual property of Van Oord UK Ltd and may not be published or distributed without written consent fromowner.

Method Statement

Dredging at Port of Cork

Port of Cork Estuary

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IMPORTANT

Any changes to working methods not identified within this method statement, will involve cessation of theworks until a full risk assessment has been conducted on these changes and the method statement has beenaltered accordingly to reflect these changes. Advice from the QHSE Department should also be sought on

these changes.

Revision record

Revision Number Description Date

1.0 First Issue 02-12-2011

2.0 Updated MS for 2014 campaign 12-12-2014

Supporting documents

Document Number Document Name

PMP-20.3432 Project Management Plan Maintenance Port of Cork

Function Initials Date Signature

Prepared by Farrell McCullough FMC 12-Dec-2013

Verified by Farrell McCullough FMC 12-Dec-2013

Approved by Godfried van Oord GOO 12-Dec-2013

Authorized by Maurits den Broeder MAU 12-Dec-2013

Document owner Staff Manager QHSE

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Distribution list

Denis Healy [Port of Cork]

Kevin OCallaghan [Port of Cork]

Harbour / Survey offices [Port of Cork]

William Brown [RPS Group]

Maurits den Broeder [Van Oord - MD]

Godfried van Oord [Van Oord - OM]

Farrell McCullough [Van Oord - WM]

Jeanette Wright [Van Oord QHSE]

Master & crew of HAM 316/HAM 317, Jetsed/Odin [Van Oord]

Newbury Operations (hardcopy) [Van Oord]

AbbreviationsHSE Health, Safety and EnvironmentITP Inspection and Test Plan

MS Method StatementPPE Personal Protective EquipmentQA/QCCDMDOMPMWMSIKpWIDTSHD

RACOSHHEMSIMSISMISPSPMPIRENLPEP

Quality Assurance / Quality ControlChart DatumManaging DirectorOperations ManagerProject ManagerWorks ManagerSuperintendentKilometer point/ChainageWater Injection DredgingTrailing Suction Hopper Dredger

Risk AssessmentControl of Substances Hazardous to HealthEnvironmental Management SystemIntegrated Management SystemInternational Safety ManagementInternational Ship and Port Facility Security CodeProject Management PlanIrelandThe NetherlandsProject Emergency Plan

Definitions

n/a

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Table of ContentsREVISION RECORD ........................................................................................................................ 2SUPPORTING DOCUMENTS .......................................................................................................... 2DISTRIBUTION LIST........................................................................................................................ 31. INTRODUCTION ....................................................................................................................... 5

1.1 General Project Description ...............................................................................................................51.2 Scope of this Document .....................................................................................................................51.3 Responsibilities ...................................................................................................................................6

2. HEALTH, SAFETY & ENVIRONMENT...................................................................................... 7

2.1 Health and safety .................................................................................................................................72.2 Personnel.............................................................................................................................................72.3 Reporting of incidents and near misses ........................................................................................... 82.4 Emergency response ..........................................................................................................................82.5 Risk assessment..................................................................................................................................82.6 Environment .........................................................................................................................................82.7 Pre-Check Procedure ..........................................................................................................................82.8 Training ................................................................................................................................................. 9

3. SCOPE OF WORKS................................................................................................................ 103.1 Scope of Works..................................................................................................................................103.2 Resources..........................................................................................................................................10

3.2.1 Personnel ...................................................................................................................... 103.2.2 Vessels .......................................................................................................................... 103.2.3 Commencement Date and Duration ............................................................................. 10

4. EXECUTION OF THE WORKS ............................................................................................... 114.1 Mobilisation and Demobilisation .............................................................................................. 114.2. General Description of Dredge activities by a Trailing Suction Hopper Dredger........................... 11

4.2.1. Loading the TSHD ........................................................................................................ 134.2.2. Sailing Full ................................................................................................................... 134.2.3. Unloading the TSHD through bottom doors / valves .................................................. 134.2.4. Sailing Empty............................................................................................................... 14

4.3. Survey ...............................................................................................................................................144.4. Work Method .....................................................................................................................................14

4.4.1. Work Method................................................................................................................ 144.4.2 Weather Conditions.................................................................................................. 14

5. ASSISTING EQUIPMENT FOR THE TSHD ............................................................................ 165.1 Scope of Works:................................................................................................................................165.2 Sequence of Works: ..........................................................................................................................165.3 Programme .........................................................................................................................................165.4 Limitations..........................................................................................................................................16

6. EQUIPMENT ........................................................................................................................... 176.1 Equipment for maintenance dredge [TSHD] ................................................................................... 176.2 Equipment for maintenance dredge [WID]...................................................................................... 19

7. SURVEY.................................................................................................................................. 21

APPENDIX 1 .................................................................................................................................. 22

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1. Introduction

1.1 General Project Description

The Port of Cork Company has awarded Van Oord ac ontract for the Maintenance Dredging in Corkfor a 7 year period. The interval between campaigns is expected to be 3 years and the firstcampaign was in 2011. This involves the dredging of silt, clay, loose and hard compacted sand andgravel and other materials, including some debris normally encountered in the execution ofMaintenance Dredging contracts.

1.2 Scope of this Document

The purpose of this Method Statement is to give an adequate description of the dredging, disposal and surveymethods to be followed and the precautions to be aware of in carrying out the works. This Method Statementwill ensure that the works will be carried out in a safe, secure and efficient way. The Risk Assessment is partof this Method Statement and should be seen as a live document which will be altered if there is any changein circumstances or knowledge

The sequence of operations described in this document is governed by weather and tidal conditions.

This Method Statement has developed and will be implemented with the health and safety and welfare of allpersonnel, the public, wild life and the environment being of utmost priority.

The contents of this Method Statement are to be verbally communicated to the workforce involved bythe Project Manager the day prior to the task commencing, this ensures that the correct personnel,tools and equipment are in place and gives enough time for suggestions or additional controlmeasures identified during the briefing to be included within the Method Statement, prior to the taskcommencing on each location.

The Method Statement will then be re-briefed in the form of a toolbox talk on the day of the activity, to ensurethat the requirements are fully understood. Feedback from the workforce is encouraged

This Method Statement is to be read in conjunction with the Project Management Plan

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1.3 ResponsibilitiesThe achievement of a satisfactory standard of quality is the responsibility of all those assigned to the project.The description of the responsibilities involved in the management of the site project team is provided in thetable below.

The following site staff have the following responsibilities:

Operations Manager Overall responsibility for ensuring safe working systems and control;

Works Manager: Coordination of the works, and the work related operations;

Superintendent: Coordination of the works, liaise with Captain/crew;

Surveyor: Responsible for all surveying work, contractual and requested.

QHSE RepresentativeJeanette Wright

ContractsManager

Project Safety

To be advised Surveyor

Van Oord tba

Operations Manager

Godfried van Oord

Works ManagersFarrell McCullough

Matthew Hellyer

Equipment Crew

/ Superintendent

Van Oord Ireland Project TeamDredging of Port of Cork

Van Oord UK - MDMaurits den Broeder

Port of Cork (Client)

Denis Healy

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2. Health, Safety & Environment

Van Oord will execute all works in line with Contract requirements, UK legislation, European, and InternationalGuidelines and Standards. In view of the potential hazards for this type of work in these circumstances and inaddition to the project related procedures, special attention is drawn to, but not limited to, the following:

2.1 Health and safety

In order to arrange, provide and maintain safe systems of work for all employees at all times:

Areas of HSE responsibility will be clearly defined and relayed to the whole project team;

Adequate and proper facilities, equipment and apparatus will be provided and its correct use will beensured, Through training, all areas are to be kept clean and tidy and personnel will be responsible forensuring their equipment is stored correctly at all times.

Adequate training, instruction and information on Site specific Health, Safety and Environmentalhazards and risks will be provided.

A pro-active approach will be taken to Health, Safety and the Environment at all times, hazard spotsand near miss reporting will encouraged throughout the duration of the project and any incidents willbe investigated ensuring that procedures and / or RAMS are updated appropriately.

2.2 PersonnelAll construction personnel involved in the work will observe the following basic working rules, amongst others:

Relevant personnel protective equipment (PPE) will be issued and used prior to thecommencement of the work;

PPE shall be worn at all times on site with exception of the dedicated safe area(s) andwelfare facilities;

Proper training and induction in the various roles for the type of activity will be performed;

Experienced and active supervision will be in place at all work times.

At least the following PPE should be worn to execute the works as described in this Method Statement:

Hi-Viz Safety Shoes Helmet Life Jacket

The indicated PPE should be worn at all times, excluding when inside the ships accommodation area.

The Life Jacket Must be worn when working near open water where no sufficient handrail or edge protection ispresent or when accessing / egressing the vessel

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2.3 Reporting of incidents and near missesIncidents and near misses will be timely reported in compliance Van Oord corporate procedure.

2.4 Emergency responseEmergency Response will be in compliance with Van Oord corporate procedure and the project EmergencyResponse Plan which is on board the dredger.

Before the start of the Project an actual plan with actual names and numbers will be made and provided to allconcerned.

2.5 Risk assessmentRisk assessments will be carried out in order to identify and control all hazards to the activities and toassociate the risk and/or reduce it to acceptable levels. The risk assessment for this method statement can befound in appendix 1.

2.6 EnvironmentIn order to minimize environmental impacts arisen from the work based on ecological knowledge and onregulatory background the following measures will be taken:

All personnel will be appropriately trained about environmental issues prior to the start of theoperation;

All equipment will be in good condition to avoid spillage or discharge of oil, smoke and

excessive noise; Refuelling will be carried out by competent and trained people away from any

environmentally sensitive areas; and dredger to be moored up securely.

An appropriate waste container will be placed to collect waste before the final disposal byauthorised company and hazardous material storage areas will be identified, labelled, andproperly marked and fitted with spill containment systems;

Dredger will be checked for any fuel / oil leaks on a regular basis by the crew.

Any spills we be reported immediately to the site agent/authorities

In the event of a major spill due to damage to the dredger. Locate and isolate, informharbour authorities, Project manager and environmental agency.

2.7 Pre-Check ProcedurePrior to commencing operations, all vessels, plant and machinery will hold relevant up-to-date certification,carry sufficient emergency oil spill kits, first aid kits and be more than adequate for their respectiveresponsibilities.

Weather reports, both long and short range, will be available on a daily basis.

All relevant stakeholders will be informed of all operational movements

Prior to commencing operations, Port Control will be contacted daily to confirm the number andextent of other ongoing works by third party contractors within the Outer Harbour area. The location,type and extent of these works will be assessed and included as part of the Risk Assessment.

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2.8 TrainingAll personnel will be competent, experienced and hold all relevant certifications, a copy of which will be heldon the site files. VOUK will provide further training, as and when required. Safe working methods will berelayed to all personnel through RAMS Briefings and toolbox talks, this will also take place following anyrevisions and changes to the RAMS

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3. Scope of Works

3.1 Scope of Works

Maintenance dredging has to be carried out in the berths, on the approaches to the berths, in navigational

channels and the harbour basins in the Port of Cork, all as is shown on the layout drawings and tablesreceived from the client.

The (river-)bottom in the designated areas shall be dredged to ensure that the design depths are providedthroughout the above described area. The design depths will be the advertised depth plus a specifiedadditional buffer depth to cater for future siltation

The method of dredging and transporting material shall be such as to avoid deposition of material in navigablechannels.

3.2 Resources3.2.1 Personnel

Site Staff:

- WM- Surveyor

Equipment

- Safe manning [as a minimum] + required for dredging. On request a Crewlist can be provided

3.2.2 Vessels

- TSHD HAM 316 or HAM 317 [or similar]

- WID Jetsed and/or Odin [or similar]

Technical specifications can be found in 6

3.2.3 Commencement Date and Duration

Sept/Oct 2014 [subject to license and equipment/projectplanning]

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P ro je c t Ma n a g e me n t P la n





4. Execution of the Works

4.1 Mobilisation and Demobilisation

The TSHD which will be made available will be scheduled to arrive in Cork at a mutually agreed startdate. Prior to arrival the Harbour Master will be informed and all required documents will be submitted.

When the TSHD arrives in the Port of Cork, the survey department will board the vessel to install thenecessary survey equipment (if required) and the latest survey information from the insurvey.

The Project Manager will also board the vessel for an Kick-off meeting / Toolbox talk

4.2. General Description of Dredge activities by a Trailing Suction Hopper Dredger

A Trailing Suction Hopper Dredger is a vessel that is suited for deep-sea navigation with the ability to loadmaterial into its own hopper by means of centrifugal pump(s) and suction pipe(s). Figure 1 shows a possiblelayout of a TSHD.

Trailing Suction Hopper Dredgers belong to the type of non-stationary dredgers. This means that TSHD arerequired to sail during dredging operations.

Figure 1 TSHD HAM 317

When the Trailing Suction Hopper Dredger approaches the dredging area, at the start of a newdredging cycle, the TSHD will reduce its speed and will put the trailing suction pipes overboard

During the approach the suction heads at the end of the trailing suction pipes will be kept a couple ofmetres above the seabed until the indicated dredging area has been reached. Once close to theindicated dredging area the dredge pumps will be started. The dredge pumps will start taking inseawater through the trailing suction pipes. The seawater that will be taken in prior to the suction

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heads touching the soil, will be pumped overboard again or in some cases remains in the hopper.

As soon as the suction heads touch the seabed and bottom material is sucked through the suctionheads and trailing pipes, the dredger operator will divert the soil mixture into the hopper by closingthe pump overboard valve, thus avoiding spillage of dredged material.

During dredging the TSHD will sail with a speed around 1 to 3 knots, depending on the dredgelocation, surrounding marine activities, sea conditions and soil parameters. Due to the speed of theTSHD the suction heads will loosen the bottom material. In this way a mixture of soil and water is

created that than can be sucked trough the suction heads, into the TSHD's own hopper. Water jetsor teeth (or both), which may be constructed in the suction heads, can assist in loosening the soil,hence optimising the production.

The material to be dredged will be stripped of the bottom in layers over the full width of thedredging area.

The position of the suction head and the trailing suction pipe can be monitored by checking thefollowing measurements:

- Measuring the pitch, heave and roll of the vessel in combination with the draught andtrim of the vessel;

- Measuring the angles of the different parts of the trailing suction pipes and suctionheads relative to a horizon with angle metres;

- Measuring the depths of the different parts of the trailing suction pipes by usingpressure readings from specially installed sensors.

As a backup system an open end thin tube from the start of the trailing suction pipe down to thesuction head is installed, through which air can be pumped under pressure. The air pressure at theexact moment bubbles appear gives an indication for the dredging depth.

The measurements as mentioned above make that the TSHD is more or less able to determine howdeep and under what angle the suction head is used while dredging. These measurements will alsogive an indication to the dredging operator in which way the profiles and depths already have beenreached.

The production of a TSHD depends on many factors, among which: soil characteristics (in-situ density,particle distribution, SPT and/or CPT values, etc...), dredging depth, weather conditions, sailing distances,marine traffic, tides, currents, etc

A dredging cycle manly exists of the following 4 consecutive operations

Loading Average trailing speed 1 to 3 knots, depending on the soil type;Sailing Full Average speed from 1 knot to maximum sailing speed, depending on wind, swell,

current, weather conditions, keel clearance and sailing distance;

Unloading Average speed from 0 knot to 3 knots sailing speed, depending on the soil type,wind, swell, current, weather conditions and keel clearance;

Sailing empty Average speed from 1 knot to maximum sailing speed, depending on wind, swell,

current, weather conditions, keel clearance and sailing distance;

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The different steps in the dredging cycle are further elaborated in paragraphs 4.2.1 to 4.2.4

The time to complete on full cycle depends on:

- The dredging time required for filling up the hopper and the load per trip will vary depending

on soil parameters, dredging depths and other circumstances.;

- The sailing time, both full and empty, depend on traffic speed limits, currents, tides,

weather conditions, sailing distances and route to the unloading area, etc...;- The unloading time depends mainly on soil characteristics.

TSHD operates 24/7

4.2.1. Loading the TSHD

The maximum volume of dredged material a TSHD can load in its hopper depends mainly on the size of thehopper and the soil characteristics of the dredged material. The same volume of dredged material can differ inweight depending on the dredge location, caused by different soil characteristics. Due to the limitations involume and weight a TSHD can carry, the maximum volume of dredged material that can be loaded dependson the volume weight of the dredged material. The TSHD will start loading dredged material into its hopperuntil the maximum volume or the maximum weight has been reached, whatever comes first.

To control the dredging position, the TSHD is equipped with a RTK-DGPS system. The TSHD is alsoequipped with an automatic suction head control system to ensure a correct dredging depth.

During dredging generally, in soft materials the drag head sinks into the soil and with a slow forwardmovement a high concentration of materials can be lifted. In firmer materials the penetration depth is lessand a greater forward speed is required to maintain a sufficient high concentration of material.

Since the dredge pumps feeds the hopper with a diluted soil / water mixture, the soil will settle in the hopperand the excess water will be discharged via an overflow. Loading can be continued until the vessel's draughtreaches the load mark or until other circumstances do not allow for further loading. When dredging lightmaterials, such as silt, difficulties may arise in the settling of the dredged material in the hopper. Under thesecircumstances, the hopper capacity is usually increased by raising the overflow.

When the hopper is fully loaded, the suction head is lifted from the bottom and the pumping system isturned off. The suction pipes will be hoisted on deck and secured onboard.

4.2.2. Sailing Full

After loading, the TSHD leaves the dredging area and proceeds to the area where the load will beunloaded. During sailing the hopper remains closed with all valves shut.

4.2.3. Unloading the TSHD through bottom doors / valves

On arrival, at the discharge location, the speed of the TSHD is reduced and the vessel is carefully positioned

in the middle of the disposal area. When the TSHD is positioned in the correct position the bottom valves areopened. All material is now discharged from the hopper in a very controlled short period.

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Unloading trough the bottom doors / valves of the TSHD can only be done if the water depth at theunloading area surpasses a minimum depth. When the required minimum depth is not available or hasbeen reached the water depth will be too shallow for the TSHD to sail / unload its next load through thebottom doors / valves.

4.2.4. Sailing EmptyWhen the hopper of the TSHD has been emptied the TSHD will set course again to the dredging location.When the dredger arrives at the dredging location, the entire dredging cycle can start over new.

4.3. SurveyFor more detailed information on the survey work reference is made to the Method Statement Survey

4.4. Work Method4.4.1. Work MethodThe area to be dredged is spread over the Port of Cork Estuary, from the City of Cork up to Ringaskiddy.

During the last dredging campaign the bulk of material was located between Black rock and LoughMahon. Therefore the TSHD Ostsee used to turn around at Tivoli.

However for this dredging campaign, due to the spread of the material, the TSHD will turn when the vessel is fullyloaded. This can be a problem in certain places where the width of the channel is limited. Therefore the dredging

sequence will be governed by tide and ship movements, e.g.: If the TSHD is going to be fully loaded half way up thelock, inbound, then it will need sufficient water to turn around in the channel wherever the TSHD will be at thatmoment. This will need to be on a flood tide. If there are shipping movements ongoing maybe the TSHD will have togo all the way up to Tivoli to turn as there is insufficient room to pass in the channel. The officer of watch will need tomake the decision each time they return form the dumping area as to where the vessel can commence dredging.

The following areas have to be dredged:

To be advised by client based on the insurvey to be done prior to the works.

City berths Tivoli berths Channel/Fairway Ringaskiddy basin and deepwater berth Turning circle Hauibowline Marino Point

Prior to start dredging Van Oord UK will meet with the Client to discuss points ofconcern, e.g. removal ofchannel buoys to allow unrestricted access for the dredger.

4.4.2 Weather Conditions

The dredging operation can be carried out during fair weather.

Limiting sea states for dredging and sand supply works are defined as Hs (significant wave height) of

approximately 1.50 metres and wind speeds of approximately 6 Beaufort.

It should be noted that wave direction, wave period, wind direction, presence of currents and combinations of

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these will influence the limiting sea states significantly.

The Master of the Vessel will determine when conditions are such that the works have to be suspended or canbe recommenced.

During periods of weather delay the TSHD can decide to go for anchorage. This anchorage can be outside thework site and not necessarily be in a harbour.

Weather forecasts will be available on a daily basis.

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5. Assisting equipment for the TSHD

Van Oord Ireland Ltd is the operator of the dredging system known as Water Injection Dredging. The Water

Injection Dredging system is unique. The silt is -in this case partially- re-liquefied by low-pressure injection of

water. The layer thus formed is a liquid denser than water, which flows under the forces of nature present in

the area, and for the works above, the gravitational force of the bed slope. Within the confines of the area, the

layer formed will flow principally under the gravitational force of the bed slope only. For the works above the

WID technique will be used for areas which are difficult to access by the TSHD, the WID will dredge the

material towards an area where the TSHD can collect this material.

5.1 Scope of Works:

To clear accumulated silts and fine sands in conjunction with the TSHD from the - by TSHD - difficult to reachdredge areas and towline dredging by use of our Water Injection Dredger Jetsed and/or Odin to the requireddepths.

5.2 Sequence of Works:

Mobilization:The dredger will be mobilised to Cork and the survey will be installed on board the dredger.

24 hours prior to arrival Port Control will be informed about the ETA of the dredger [under tow in case of theJetsed and by lorries in case the Odin will be used]

Dredging Operations

The objective is to remove silts and fine sand in conjunction with the TSHD. The WID unit will prepare thedredge area for the TSHD by sweeping material out of berth boxes and near and under fenders/jetties.

5.3 ProgrammeThe dredging programme will be to work on a 6 hour working window and 6 hours off for the crew.

On daily basis a daily report will be submitted, a copy of the track plots per tide will be submitted as well.

5.4 LimitationsBig rocks or boulders and/or debris cant be removed by using the water injection dredger but will be markedon the survey if applicable and can be dredged [to a certain limit by the TSHD].

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6. Equipment

6.1 Equipment for maintenance dredge [TSHD]

TSHD HAM 317

Construction 2000Dimensions Length overall 97.26mBreadth 18.40mMoulded depth 8.60mDraught maximum 7.51mMaximum dredging depth 37.1mHopper capacity 4,500m3Total power installed 6,132kWSuction pipe diameter 0.90m

- Cycle time depends on dredge location/soil parameters, weather and shipping.- Tonnage Dry Substance: approx. 1,900/load [approx. 2,750m3/load]

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TSHD HAM 316

Construction 1998

Dimensions Length overall 128.46mBreadth 22.05mMoulded depth 10.00mDraught maximum 9.93mMaximum dredging depth 40.3mHopper capacity 9,535m3Total power installed 11,890kWSuction pipe diameter 1.10m

- Cycle time depends on dredge location/soil parameters, weather and shipping.

- Tonnage Dry Substance: approx. 4,000/load [approx. 8,250m3/load]

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6.2 Equipment for maintenance dredge [WID]

WID dredger Jetsed

Name: JetsedConstruction 1987Dimensions Length overall 37.34mBreadth 13.85mMoulded depth 13.80mDraught maximum 1.40mMaximum dredging depth 24.90mWidth injection pipe 13.40mPropulsion 3 x 1x265kW; 1x380kW and 1x364kWTotal power installed 1,971kWJet pumps 1x452kW and 1x400kW

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WID dredger Odin for toe line dredging

Construction 2007Dimensions Length overall 14.50mBreadth 4.50mMoulded depth 1.80mDraught maximum 1.45mMaximum dredging depth 12mWidth injection pipe 4.40mPropulsion 2 x 89kWTotal power installed 410kW

Jet pump 220kW

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7. Survey

A separate Method Statement for the survey works has been submitted and is applicable for the duration ofthe contract. Any updates required will be submitted prior to the commencement of the works.

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Appendix 1

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Project Name: Port of Cork Maintenance DredgingProject stage: Maintenance Dredging

Project no:20.3432 RA document number: SM 001

Revision / Date: 13-Dec-2013 rev. 2.0

Prep:FMC Authorised: GOO Reference: Page 1 of 1 pages

Document number: VOMS-PR1.10-TE-01Prepared by: QHSERev. 1, 13-10-2011

Attendees:

Name Job Company Name Job Company

RA chairman:

Farrell McCulloughGodfried van Oord

tba

Works ManagerOperations Manager

Surveyor

Van OordVan Oord

Van Oord

Crew TSHD/WID

Itemno.

Activity Hazard ConsequenceInitialRisk Van Oord Existing

Safeguards

AdditionalSafeguard

Vessel / ProjectBy Completion

Reference

ResidualRisk

S L R S L R

Working on or nearwater on board thevessel

Insufficientbarriers,Edge protection.

Falling in water causingHypothermia/drowning

4C

Barriers to beinspected prior towork.Experienced crew.Kick off meetingbefore works.Emergency rescueplan in place forMOB.Regular serviced lifejackets while ondeck.

No lone working.Sand/salt for non-slipdecks.

FMC 2C

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R

Access & Egressonto jetty.Using a ladder

Falling in water causinghypothermia/drowninghead/minor injury

4C

Use ladder in correctway.Only step across ifsafe to do so.

Make clearinstruction of yourintentions to othercrew member.Wear life jacket.

Moore up on floatingpontoons(so noclimbing).

FMC 2C


Working on deckat night

Falling in water causinghypothermia/drowninghead/minor injury

3B

Adequate lighting.Crew work together.Goodhousekeeping(cleandecks).Competent crew.Monitoring of waterlevels.First aider on board.Good radiocommunications.Avoid working on

deck at night.

Stay in wheelhouse atnight.Only moore up whenalongside.

FMC 2B

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R


Breaking mooringropes.

Injury 2b

Inspection of mooringropes before use.Monitor weatherconditions.

Dont lose sight ofoperator,communicate whatyou are doing.No excess force onropes from enginepower.

Competent crew FMC 1A

Working on or nearwater on board thevesselsSlips trip,& falls.

Wet surfaces. Serious injury.

Fracture.bruising

3C

Good housekeepingon deck.Correct nonslip safetyshoes.Minimise work ondeck.


Obstructedwalkways

Serious injury.Fracture.bruising

3C

Plan storage ofmaterials.Clean & tidy deck.Put stores away

immediately.


Cables onwalkways


3cUse cable covers.Use signage.Avoid any trip hazard.


Insufficient lighting injury 2B

Make sure all decklights are workingwith spare bulbsavailable.


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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R

Working on or nearwater on board thevesselSlips trip,& falls.

Inappropriatefootwear.

Serious injuryFalling overboard

3B Safety shoes are

compulsorySafety shoes renewedon request.

FMC 2B

Greasy / oilysurfaces


3B

Clean spillagesimmediately.Spill kits available.Good housekeeping.Degreaser available.Report all spillages.

Clean tidy decks FMC 2B

Tripping over.Catching looseclothing on deck.Edge protectionnot in place.Ice.Not payingattention.


3b

Barriers inspecteddaily.Competent persons.Toolbox talk on slipstrip & falls.No lone working.Emergency rescueplan in place.Clean decks.Good lighting.Serviced life jacketsworn.

Monitor weatherconditions.No loose clothing.Wear overalls.

Salt bags on standbyfor cold weather.

FMC 2b

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R

Wire handling Hand injury 3b

Wear gloves.No lone working.Inspect wire for anydeficiencies.

Avoid any wire work. FMC 2b

Working on or nearwater on board thevesselTidal works

Lone working.Stress.Lack of sleep.

Antisocial behaviour.Ill health.Lack of performance.Lack of concentration.

3b

No lone working.Agreed hours ofwork.6 hours off work in-between tides.Take breaks (shareoperating).Health assessments.

Keep working hours toa minimum for crew.Crew works 14 dayson 14 days off

FMC 2b

Working in verycold conditions.

Hypothermia Time off work 2c

Wrap up warm ondeck.Hat & gloves.Take regular breaksin heated wheelhouse.Take extra care on

deck.Dont rush.

Monitor weather FMC 2b

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R


Noise

Over exposure tonoise inengine/pump

room.

Tinnitus.Ringing in ear.Loss of hearing. 2c

Use ear defenders.Noise monitoring.Display signs.No more than 5

minutes exposure.

No going in engineroom or pump roomwhile working.

FMC 1b

Manual handling Lifting heavy itemsSevere back pain.Muscle pain.Lifelong back pain.

3b

Wear possible uselifting aid.Manual handlingtraining to crew.Know the weight youare lifting.Can you spilt the loadto smaller weights.No trip hazardspresent.Avoid repetitivehandling.

Competent crew FMC 2b

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R

Manual handling Lifting heavy items

in wrong way.

Severe back pain.Muscle pain.Lifelong back pain.

3b

Instructions of correctlifting method.Use mechanical aidwear possible.

Make sure no fingerscan get trapped.No obstructions inway.Good handles onitem to be lifted.Do not push or pullload thats heavy.Do not lift if history ofback problems.

Competent crew FMC 2b

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R

COSHH Hazardous

substances.

Fire & explosion.Exposure.Inhalation of toxicsubstances.Contact with skin.

3b

All substances storedin well ventilated &lockable containers.Signage in place.

Fire extinguishers inplace.COSHHassessments for allon board chemicalsavailable.No smoking signs.Appropriate PPEavailable.Crew aware of what& wear on board.Spill kits on stand bywhile refuelling.Stop any leakage inwater course usingspill kits.

FMC 2b

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R

Refuelling Refuelling

Environnementaldamage.Skin & eyecontamination.Explosion,fire,burns.

3c

Coshh assessmentsavailable.Wear proper PPE.Ensure fuel caps are

replaced.Delivery fromprofessionalcompany.Designated fuellingplace.Spill kits available.Drip trays available.Pollution preventionplan available.Booms available.Eye wash stationavailable.Emergency phonenumbers available.

FMC 2c


Swell Damage to crew and

equipment 4C

Standing instructionnot to dredge when

swell is above 1.5mfor TSHD and 0.5 forWID and/or whenskipper is notcomfortable todredge

FMC 2c

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Itemno.


Safeguards

AdditionalSafeguard


Reference

ResidualRisk

S L R S L R

Shipping

Collision/interference shipping withdredgingoperations

Damage to crew andequipment and portfacilities

3c

Stay in contact withPort Control via VHF.Especially duringdredging the berths,

extra care should betaken.

Dredging in anotherarea as directed byport control in case ofshipping

HM/Port Control to

provide an dailyupdate aboutexpected shipmovements that day

FMC 2c

Others Live Document

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Port of Cork Maintenance Dredging Application

Volumes / Tonnages Being Applied For

For Each Main Campaign years 2014, 2017 and 2020 For Each Interim Campaign years 2015 &

Main Loading Areas by Trailer Suction Hopper Dredging Trigger Areas / Berths by Bed Levelling / Water Injec

Location Volume (m3

) Wet Tonnage (t) Location Volume (m3

City Quays Horgan's Wharf 4,100 4,510 Confluence of North and South Channels total below

City Quays North Deepwater Quay 2,200 2,420 Blackrock Castle Bend total below

City Quays Albert Quay 1,250 1,375 Ringaskiddy Approach Basin total below

City Quays South Jetties 5,750 6,325

City Quays South Deepwater Quay 1,250 1,375 Local Access Dredge Areas by Bed Levelling / Wate

Bottom of Lough 67,600 74,360

Tivoli Quigley Berth 5,000 5,500 Location Volume (m3

Tivoli Container Berth 750 825 Ringaskiddy Slipway and Pier total below

Tivoli RoRo Berth 1,250 1,375 NMCI Loading Area and Drop Pool total below

Tivoli Oil Jetty 1,250 1,375 Cobh Boat Camber total below

Lough to Passage 200,100 220,110

Haulbowline Industries Berth 7,000 7,700 20,00

Ringaskiddy Approach Basin 35,000 38,500

Ringaskiddy Deepwater Slot 10,500 11,550 .shp files are provided for each of these locations as line

Whitegate 3,000 3,300Passage to Roche's Point 6,000 6,600

352,000 387,200

.shp files are provided for each of these locations as areas individually to both ITM and WGS84

Breakdown of Quantities per Year

Year Volume (m3) Wet Tonnage (t) Method of Dredging

2014 352,000 387,200 Trailer Suction Hopper Dredging

2015 20,000 22,000 Bed Levelling / Water Injection Dredging






Totals 1,136,000 1,249,600

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Appendix A

Water Injection Dredging Tracer Study Cork

Environmental Impact and Sediment Transport

Study Utilizing Fluorescent Particle Tracers

Final Report

July 2012

Van Oord

Submitted by:

ETS Worldwide Ltd

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Water Injection Dredging Tracer StudyCork. Environmental Impact and Sediment Transport Study

ETS Worldwide Ltd

1

AUDIT INFORMATION

Water Injection Dredging Tracer Study Cork

Environmental Impact and Sediment Transport Study Utilizing FluorescentParticle Tracers

Final Report Version 1.0

Client Name: Van Oord Dredging

Client Contact: Farrell McCullough

Project Director Dr. Jonathan Marsh

Project Manager Fraser Taylor

Fieldwork conducted by: - Fraser Taylor / Aquatic Marine

Report written by: - Dr. Jonathan Marsh / Isabel Labrador / Amy Parry

Data processing undertaken by: Fraser Taylor / Isabel Labrador

Report authorised by: - Dr. Jonathan Marsh

Date Issued: - 10 July 2012

Client: Farrell McCullough, Project ManagerVan Oord UKLockside Place, Mill LaneNewbury, Berkshire, RG14 5 QS

Tel: +44 1635 529101

Mob: +44 7860 928134Fax: +44 1635 521548Email: [email protected]: www.vanoord.com

Contractor: Dr. Jonathan Marsh, Managing DirectorETS Worldwide LtdThe Coach House, BannachraHelensburgh, G84 9EF

Tel: 01389 711001Fax: 01389 850551Email: [email protected]: www.environmentaltracing.com

Certificate No. GB2001513 Registration No. 0044/1

INTERN TION L

CCREDIT TION BO RD

ISO 9001

REGISTERED FIRM

INTERNATIONAL

ACCREDITATION BOARD

This document is confidential. The copyright remains with ETS Worldwide Ltd, The Coach House, Bannachra, Helensburgh,G84 8EF. All rights reserved. Neither the whole nor any part may be disclosed to any third party nor reproduced, stored in any retrieval system, ortransmitted in any form nor by any means (electronic, mechanical, reprographic, recording or otherwise) without the prior written consent of ETS Ltd.

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2

Table of Contents

1. Introduction .................................................................................................................................... 5

2. Sediment Tracer Characteristics and Deployment .............................................................................. 7

2.1. Tracer Colour .......................................................................................................................... 72.2. Tracer Particle size .................................................................................................................. 72.3. Tracer Density ........................................................................................................................ 82.4. Tracer Mixing and Release ....................................................................................................... 9

3. Field Equipment and Methodology .................................................................................................. 12

3.1. Seabed Sampler .................................................................................................................... 123.2. Sampling Survey ................................................................................................................... 12

4. Data and Results ........................................................................................................................... 16

4.1. Magenta tracer results ........................................................................................................... 16

4.2.

Yellow tracer results .............................................................................................................. 20

5. Summary of Results ...................................................................................................................... 23

6. Interpretation and Mass Budget Calculation .................................................................................... 25

References ........................................................................................................................................... 31

APPENDIX A Settling Velocity Tests ........................................................................................................ 32

APPENDIX B Laboratory and Tracer Analysis Methods ............................................................................. 34

B.1. Standard Laboratory Procedure .............................................................................................. 34B.2. Sample Analysis Techniques .................................................................................................. 34

B.3. Controls and Replicate Analysis .............................................................................................. 36B.4. Microscope Photographs ........................................................................................................ 36F

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3

List of Figures

Figure 1.1. Study Area, Cork and Ringaskiddy ........................................................................................... 5

Figure 2.1. Release sites for the yellow and red tracers ........................................................................... 10

Figure 3.1. Van Veen Grab sampler........................................................................................................ 12Figure 3.2. Map of background sampling locations.................................................................................. 13Figure 3.3. Map of sampling locations for Cork City and Ringaskiddy........................................................ 15

Figure 4.1. Cork Round 1 Magenta Tracer silt fraction results per cm2...................................................... 18Figure 4.2. Cork Round 2 and Ringaskiddy Round 1 Magenta Tracer silt fraction results per cm2................ 18Figure 4.3. Cork Round 3 and Ringaskiddy Round 2 Magenta Tracer silt fraction results per cm2................ 19Figure 4.4. Ringaskiddy Round 3 Magenta Tracer silt fraction results per cm2........................................... 19Figure 4.5. Cork Round 2 and Ringaskiddy Round 2 Yellow Tracer silt fraction results per cm2................... 21

Figure 4.6. Cork Round 3 and Ringaskiddy Round 3 Yellow Tracer silt fraction results per cm2................... 22Figure 4.7. Ringaskiddy Round 3 Yellow Tracer silt fraction results per cm2.............................................. 22

Figure 5.1. Areas used for mass budget calculations ................................................................................ 26

Figure A.1. Cumulative silt only and silt and tracer composite weights retained over 240 minutes .............. 33Figure A.2. Cumulative Magenta and Yellow silt-sized tracer counts per milligram retained over 240 minutes

.................................................................................................................................................... 33

Figure B.1. Fluorescence micrographs of the magenta tracer particles from actual samples under white light(left) and fluorescence illumination (right) ...................................................................................... 37

Figure B.2. Fluorescence micrographs of the yellow tracer particles from actual samples under white light(left) and fluorescence illumination (right). ..................................................................................... 37

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4

List of Tables

Table 2.1. Summary of particle size data for natural sediment and manufactured tracer.............................. 7

Table 2.2. Tracer release summary for Cork............................................................................................ 10

Table 2.3. Tracer release summary for Ringaskiddy................................................................................. 11

Table 3. 1. Summary of Activities and calendar ....................................................................................... 14

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5

1. Introduction

The Port of Cork is the key seaport in southern Ireland, comprising of a significant natural harbour and a

river estuary at the mouth of River Lee located in County Cork (Figure 1.1). The Port of Cork are responsible

for port operations, navigation and safety in the port and carry out maintenance dredging to maintain

navigable depths in the port facilities including Cork City berths, Ringaskiddy and Cobh Deepwater Quay

(Figure 1.1).

Figure 1.1. Study Area, Cork and Ringaskiddy

Port of Cork contracted Van Oord UK Ltd. to carry out water injection dredging (WID) in the Cork City berths

and Ringaskiddy. WID involves jetting large quantities of water under low pressure into the sediment,

generally slit or very fine sand, to fluidise the settled material. This process breaks down the cohesion of the

sediment to form a fluid dense sediment layer which then moves under the influence of gravity and density

gradients. The aim of this type of dredging is not to raise sediments into the water column, but to keep

them restricted to the nearbed area. Where properly applied, environmental effects due to suspended solids

are greatly minimised as they are restricted to the vicinity of the seabed.

WID can provide a cost effective approach to dredging given it does not need a sea disposal licence and

avoids the cost of trailer suction hopper dredgers and possibly hopper dumping at sea. WID can also be

relatively flexible in confined areas such as harbours, marinas and around berths and pontoons due to the

small size of the dredging plant. WID is considered to be beneficial to sediment management in a given area

since the sediment is retained within the local system rather than taken out of that system and disposed of

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6

at sea, possibly in an area that does not have similar sediment properties to the maintenance dredge

material.

During dredging in the Port of Cork, Van Oord UK Ltd. and the Port of Cork commissioned bathymetric

surveys and suspended sediment monitoring. ETS Worldwide Ltd. (ETS) was contracted to undertake asediment tracer particle study to label and track the movement, deposition and ultimate fate of the WID

material from Cork City and Ringaskiddy. ETS has previously conducted nine similar WID studies throughout

the UK and Ireland including a study in County Waterford. ETS have also conducted over 85 sediment

transport studies worldwide over the past 20 years. ETS fluorescent tracer product has been included in

over 15 scientific papers and journals.

In order to assess the effects of WID in River Lee ETS released two tracers:

Magenta tracer was released during dredging at Cork City and monitored throughout the River Leedownstream as far as Lough Mahon.

Yellow tracer was released during dredging at Ringaskiddy and was monitored in nearby

depositional areas, such as the Monkstown Creek mudflats, and environmentally-sensitive areas

such as Oyster Bank.

This document details:

Chapter 2: Tracer characteristics and releaseChapter 3: Field equipment and sampling methodology

Chapter 4: Results showing patterns of sediment tracer deposition of Magenta and Yellow tracers

including temporal and spatial distributions of tracer particles by size

Chapter 5: Discussion and conclusions.

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7

2. Sediment Tracer Characteristics and Deployment

2.1. Tracer Colour

In order to distinguish between the two different areas of dredging and the sediment re-distributed from

Cork City and Ringaskiddy, ETS manufactured two different fluorescent silt tracers. Magenta tracer was

released at Cork City and Yellow tracer was released at Ringaskiddy. The tracers were designed to mimic the

silt-size fraction re-distributed as a result of WID dredging in order to monitor the movement and fate of this

material spatially and temporally. To ensure this is achieved it is very important to make sure the tracer

particles match the natural sediments in terms of size, density and ultimately behaviour in terms of

flocculation and settling characteristics.

2.2.

Tracer Particle size

Van Oord UK provided ETS with particle size data for the natural sediment for Cork City and Ringaskiddy

based on five samples; the data in microns (m) are summarized in Table 2.1. Also detailed in Table 2.1 are

the particle size data for the silt tracer particles for each site. N.B. ETS only intended to mimic the silt

fraction of the dredged sediment for both sites, therefore to make the study and data comparable ETS

ensured that the tracer particles were similar in size.

Table 2.1. Summary of particle size data for natural sediment and manufactured tracer

Site D10 D50 D90

Ringaskiddy 3.8 14.2 65.6

Cork City 8.6 51.2 360.2

Magenta tracer

(Cork City)4.0 12.0 62.3

Yellow tracer

(Ringaskiddy)3.6 11.1 61.9

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9

sediment from the site, they flocculated and settled in a very similar way to the natural sediment without

tracer, indicating they do not affect the movement of the sediment and also behave in a very similar way

under laboratory conditions.

2.4.

Tracer Mixing and Release

As previously described, Van Oord UK Ltd were proposing to dredge within two areas or sites; the upstream

area of the River Lee and Cork Harbour and the downstream area at Ringaskiddy. In order to assess the

movement and re-distribution of the sediment from WID in each area, ETS released magenta tracer in Cork

City and yellow tracer in Ringaskiddy as shown in Figure 2.1. In order to ensure that tracer was spread over

the entire area of dredging, the tracer particles were released in batches over several hours, at different

locations within the highlighted areas in Figure 2.1. The WID and tracer releases took place during ebb tide

conditions to ensure that the tracer particles were dispersed and transported downstream for each site away

from the dredge area.

ETS shipped the tracer particles in dry powder form and then wetted the material prior to release by

mixing the powder with seawater/river water in a large barrel with an electric drill and paddle. This

preliminary mixing prevents particles becoming airborne and contaminating the survey site, and facilitates

pumping of the tracer during release. Due to the interest and area of concern for material dredged in Cork

City and the extent of the sampling area principally covering Lough Mahon, ETS released 150 kg of Magenta

tracer in Cork City and 100 kg of Yellow tracer in Ringaskiddy since the area of interest was smaller.

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10

Figure 2.1. Release sites for the yellow and magenta tracers

2.4.1. Magenta Tracer Release Cork City

The Magenta tracer was released in six discrete batches on 30 August 2011 between 07:30 and 12:10 over

the ebb tide (HW+0.5 to HW+5.1) throughout the dredging area as detailed in the Table 2.2. The releases

were carried out one day before the spring tide. The weather conditions on 30 August were dry with a slight

wind (~Force 12).

Table 2.2. Tracer release summary for Cork

Release Mass oftracer

Time Time Relative to HW Dredger Position(Chainage)

1 25 kg 07:3007:53 HW+0.5 to HW+0.9 11990

2 25 kg 08:3008:40 HW+1.5 to HW+1.7 475510

3 25 kg 09:1509:25 HW+2.3 to HW+2.5 27001800

4 25 kg 10:3710:40 HW+3.7 ~560

5 25 kg 11:1511:19 HW+4.4 ~1480

6 25 kg 12:0512:10 HW+5.1 ~1100

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11

2.4.2. Yellow Tracer Release Ringaskiddy

The Yellow tracer was released in four discrete batches on 6 September 2011 between 13:04 and 13:48 just

after high water throughout the dredging area as detailed in the Table 2.3. The releases were carried out

one day before the neap tide. The weather conditions on 6 September were wet with a strong wind (~Force

56).

Table 2.3. Tracer release summary for Ringaskiddy

ReleaseMass oftracer

Time Time Relative to HWDredger Position

(Chainage)

1 25 kg 13:0413:06 HW+0.1 ~14400

2 25 kg 13:1513:17 HW+0.3 ~14404

3 25 kg 13:3013:32 HW+0.5 ~14322

4 25 kg 13:4613:48 HW+0.8 ~14726

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3. Field Equipment and Methodology

3.1. Seabed Sampler

Seabed sampling was carried out using a Van Veen grab, which can be operated from a small vessel, if

required, allowing access to shallow water sites. The Van Veen grab (Figure 3.1.) is a lightweight sampler

designed to take large samples in soft bottoms. Its long lever arms and the sharp cutting edges on the

bottom of the scoops, enable it to cut deeply into the softer bottoms. The Van Veen grab sampler is

manufactured in two sizes from stainless steel. The weighted jaws, chain suspension, and doors and screens

allow flow-through during lowering to the bottom and assure vertical descent where strong underwater

currents exist. The relatively large surface area and the strong closing mechanism allow the jaws to excavate

relatively undisturbed sediments. When the powering cable is slowly made taut, the chains attached at the

top of the release exert great tension on the long arms extending beyond the jaws, causing them to lift, dip

deeper into the sediment, and trap material as they tightly close. The stainless-steel, 583 m, door screens

have flexible rubber flaps which, during lowering, are lifted. When the grab settles on the bottom, the flaps

fall back and cover the screens completely, preventing any loss of sediment during retrieval.

Figure 3.1. Van Veen Grab sampler

3.2. Sampling Survey

3.2.1. Background sampling

Prior to a sediment tracer study, ETS typically collect background sediment samples from the study site,

before manufacturing the sediment tracers, to confirm presence of any fluorescence material and also

characterize the sediment, especially particle size. However, due to the timescales involved in this project

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there was insufficient time to collect and analyse background samples and use the information obtained to

produce an optimum silt particle tracer, in terms of colour (minimal interference with naturally occurring

fluorescence), density and particle size. Therefore ETS manufactured two silt-sized tracers with similar size

distributions and generic individual grain densities for marine silt sediment. In terms of fluorescent colour,

ETS chose two colours, which are easy to detect over and above any natural fluorescence present in marine

sediment.

In order to have some information on any background fluorescence present at the site, immediately after

arrival at the site, ETS collected background samples prior to the release of the tracer particles. These were

analysed in order to determine any fluorescence material at the sampling sites. The background samples

were also collected in order to asses the suitability and accessibility of each of the proposed sampling

locations for future sampling events.

Background sediment grab samples were collected by boat from 35 sites throughout the study area,

focussing on areas where silt is likely to deposit, along with samples from environmentally-sensitive sites,

such as shellfish banks (Figure 3.2.).

Figure 3.2. Map of background sampling locations

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Documents

Project Management Plan Dreddging