TRANSNET SOC LTD 3) FOR THE 203 and 205 L...TRANSNET SOC LTD FEASIBILITY STUDY ... METHOD STATEMENT: ... Determined the extent of dredging at the toe of the existing sandbank, the

TRANSNET SOC LTD

FEASIBILITY STUDY (FEL 3) FOR THE DEEPENING OF BERTHS 203 and 205

PORT OF DURBAN

Contract Number: TCP CON/041/2011/005

Task Order Number: TO‐TCP‐001

Project Number: M‐2122830‐408

METHOD STATEMENT: ZAA 1370‐MS‐016 REV 00

EXTENSION OF SANDBANK

25 September 2012

TRANSNET SOC LTD

FEASIBILITY STUDY (FEL 3) FOR THE DEEPENING OF BERTHS 203 AND 205

PORT OF DURBAN


ZAA 1370 | MS | 016 Rev 00 September 2012

REVISIONS

REV DATE DESCRIPTION DESIGNED

BY

CHECKED

BY

APPROVED

BY

00 25 September 2012 Draft CJE JZ JZ

AUTHORISATION

AUTHORISED BY NAME SIGNATURE DATE

DIRECTOR J ZIETSMAN

25 September 2012

This document, including all design and information therein, is Confidential Intellectual Property of ZAA Engineering.

Copyright and all other rights are reserved by ZAA Engineering.

This document may only be used for its intended purpose.

TRANSNET SOC LTD


PORT OF DURBAN



CONTENTS

1.0 INTRODUCTION ....................................................................................................................................... 1

2.0 SCOPE AND PURPOSE .............................................................................................................................. 2

3.0 RESPONSIBILITIES .................................................................................................................................... 2

3.1 Design .............................................................................................................................................................. 2 3.2 Approval .......................................................................................................................................................... 2 3.3 Execution ......................................................................................................................................................... 2

4.0 SCOPE ...................................................................................................................................................... 3

4.1 Drawings ......................................................................................................................................................... 3 4.2 Description ...................................................................................................................................................... 3 4.3 Quantities ........................................................................................................................................................ 3

5.0 SEQUENCE ............................................................................................................................................... 3

6.0 METHOD .................................................................................................................................................. 4

7.0 ENVIRONMENTAL CONSIDERATIONS AND POLLUTION CONTROL ............................................................ 4

7.1 General ............................................................................................................................................................ 4 7.2 Specific Measures ........................................................................................................................................... 4

8.0 RISK ASSESSMENTS.................................................................................................................................. 5

9.0 PROGRAMME .......................................................................................................................................... 5

10.0 QA & QC .................................................................................................................................................. 5

11.0 HEALTH AND SAFETY ............................................................................................................................... 5

12.0 SPECIFICATIONS ....................................................................................................................................... 5

13.0 DRAWINGS .............................................................................................................................................. 5

14.0 RESOURCES AND EQUIPMENT ................................................................................................................. 5

15.0 RECORDS ................................................................................................................................................. 5

ANNEXURES ............................................................................................................................................................. 1 ANNEXURE 1 – DRAWINGS ....................................................................................................................................... 2

TRANSNET SOC LTD


PORT OF DURBAN



Page | 1

1.0 INTRODUCTION

This Method Statement is prepared as part of the Contract awarded to ZAA Engineering Projects and Naval

Architecture (Pty) Ltd, (ZAA), by TRANSNET SOC Ltd, for the Feasibility Study (FEL‐3) for the deepening of Berths 203

– 205 in the Port of Durban.

Left Port of Durban

Below – Pier 2, Berths 203 to 205

The Method Statement is one of a series that have been developed, and where necessary updated, to define at high

level the responsibilities and the procedures that must be implemented by ZAA, Transnet and the ultimate

contractor to be appointed when the project proceeds to the FEL‐4 implementation stage.

The methodologies will be subject to confirmation following the formal appointment of a contractor.

TRANSNET SOC LTD


PORT OF DURBAN



Page | 2

2.0 SCOPE AND PURPOSE

This Method Statement defines the procedures to be adopted for the reclamation and extension of substantial areas

of the sandbanks opposite the new construction work at Berths 203 to 205

The purpose of this Method Statement is to define in advance the extent of the work, the division of responsibilities

and the required modus operandi of all parties.

The desired outcome is thus to ensure that all operations for the preparation and placing of high quality reclaimed

material for the extension of the sandbank is carried out safely and in a manner that disturbs the environment to the

minimal extent possible. Measures are to be implemented to ensure the work is done in accordance with the

specified environmental requirements, design and standards; to the required tolerances; in the correct sequence and

to the required programme for the works.

3.0 RESPONSIBILITIES

3.1 Design

It is the responsibility of the designer, ZAA Engineering Projects and Naval Architecture (Pty) Ltd, (ZAA) to carry out

the following work in order to define the reclamation work required for the sandbank extension.

ZAA will have

Assessed the available and new geotechnical and survey data

Established sources of sand from the offshore borrow site

Determined the extent of reclamation and extension of the sandbank, as well as specifications for

the material and its placing

Determined the extent of dredging at the toe of the existing sandbank, the bottom slope protection

required and the required profiles of the extended surfaces

Investigated the suitability of dredged material for stockpiling and later use for reclamation

ZAA will further provide:

Detail reclamation and extension drawings and quantities

Specifications of the reclaim material – sources, properties and grading

Instructions for placing

Control and monitoring measures to minimize turbidity of the water column

Construction sequence during placing

QA / QC requirements and record keeping

Tolerances and required surveys during and after placing to ensure that the requirements are met

3.2 Approval

It will be the responsibility of the client (TCP) to

Approve all drawings and procedures to Approved for Construction (AFC) Stage

Define borrow sites for sourcing reclaim material

Obtain licenses and environmental approvals for dredging and placing of reclaimed material

Appoint and negotiate details with the Contractor

3.3 Execution

It will be the responsibility of the Contractor to

Review and accept or make proposals for the modification of all designs and procedures

Provide his own detailed method statements for execution, based on his own available resources,

plant and internal procedures

Produce, update and maintain his own detailed construction schedules for all phases of the works.

Manage the contract

TRANSNET SOC LTD


PORT OF DURBAN



Page | 3

Take possession of the site

Provide suitable plant – dredger and distribution systems plus additional facilities and equipment for

placing of reclaim material

Obtain suitable sources of material and provide samples for approval.

Provide initial, progress and completion surveys to confirm compliance with design requirements as

well as measurement for payment purposes.

4.0 SCOPE

4.1 Drawings

The scope of work required is shown on the following drawings (attached as Annexure 1).

1370‐DWG‐1700 Rev P02 – Berth 203 to 205 Deepening – Dredging ‐ General Layout Option 3G

1370‐DWG‐1710 Rev P00 – Berth 203 to 205 Deepening – Dredging – Mooring Basin Layout Option

3G

1370‐DWG‐1711 Rev P00 – Berth 203 to 205 Deepening – Dredging – Sections Option 3G

4.2 Description

The drawings show dredging layout Option 3G, which defines a tapering basin opposite the new berths 203 to 205 as

well as a deepened turning basin between the existing T‐jetty and Pier 1. The new basin will be deepened from its

current nominal depth of ‐12.8 m CDP to ‐16.5 m CDP.

The tapered shape of the deepened basin permits a substantial extension of the sandbanks, which offsets the smaller

areas that will be lost to the turning circle and the extension of Berth 205 into the existing crane area.

The sections show the current profile of the sandbank, which has been found to have a natural slope of

approximately 1:4. Its top is in the intertidal zone at a nominal elevation of 0.0 m CDP. It is thus exposed at low tide

and inundated at high tide. As shown in the second section, it is the intention of the reclamation and extension to

replicate the natural profiles. Tidal flows will over time modify this slightly to establish a fully stable extended

surface. Being a contiguous extension rather than a new area, it is expected that the spread of ecological systems to

the extended area will be relatively quick.

The new dredged basin will be deepened to ‐16.5 m CDP at a 1:3 slope and scour protection is to be provided to

protect and stabilize the new toe of the sandbank. This will extend down the 1:3 slope and for 10 m along the new

basin floor at ‐16.5 m CDP. In addition it will be lapped over the top of the slope at the current ‐12.8 m CDP level.

4.3 Quantities

The estimated quantity of sand to be dredged and placed is approximately 1,000,000 m3. Based on a single 2,700 m3

TSD and with a bulking factor of 1.12 a nett deposition of about 1,800 m3 could be expected per dredged load. This

requires some 550 loads at a cycle time of some 6 hours. Thus the maximum sand deposition rate will be of the order

of 5,400 m3 / day which would take at least 6 months of uninterrupted work. It should be noted that the actual

equipment available to and selected by the contractor may change these rates and durations significantly.

5.0 SEQUENCE

The major part of this work will be carried out during Phase 1 of the work, during which the basin and turning circle

will be dredged to its new depth and the slope protection installed. Phase 1 also includes the construction of the new

Berth 205 and the deepened basin and turning circle must be available for the larger ships that will use Berth 205

after it is commissioned. Extension of the sandbanks will progressively follow the dredging work.

TRANSNET SOC LTD


PORT OF DURBAN



Page | 4

6.0 METHOD

The following procedure provides a simplified, high‐level overview of the Contractor’s process of reclamation and

extension of the sandbanks. Note that the methodology for basin and turning circle dredging as well as slope

protection is not covered by this document.

Set up a survey programme, determining setting out points of the area to be filled. This must be

compared with previous surveys and the baseline agreed

Conduct a video survey of the existing slopes for record purposes

Set up pollution control measures – refer to Section 7 below

Mobilise and commission suitable dredging equipment, marine operating staff, diving crews and

support boats. The anticipated dredging equipment is a Trailing Suction Dredger (TSD), fitted with

discharge pumps and hoses from a bow coupling.

Dredge clean reclaim material from designated and approved borrow site offshore

Provide samples for confirmation of suitability of material

Place sandbags along the line of the new toe of the extended sandbank to form a low retaining

structure. Bio‐degradable sandbags would be preferred.

Pump the reclaim material behind the sandbag retaining structure in a sequence so that the area is

filled evenly and rises in layers from below. This procedure will reduce entrainment of sand in the

water column and thus reduce turbidity.

Monitor turbidity in the water column and adjust deposition rates as needed.

Fill to the pre‐determined level, with periodic dives providing video records of the new profile.

Conduct interim and acceptance surveys for confirmation of final levels achieved and for

measurement of quantities.

7.0 ENVIRONMENTAL CONSIDERATIONS AND POLLUTION CONTROL

7.1 General

Despite being an industrial site for many years and thus being in a more or less degraded state in places, good

environmental Management of the Port of Durban nevertheless remains an absolute priority. All aspects of the

project will be subject to detailed environmental scrutiny into the construction related and long term operational

effects on the environment, both locally and in the wider context of the Port and its surroundings, land and marine.

In particular underwater operations, or those resulting in potential spillage of material, pose substantial

environmental challenges that have to be very carefully managed.

ZAA will identify at an early stage the potential Environmental Concerns resulting from placing the

reclaim material, as well as mitigatory procedures.

TCP will refer all issues to the Environmental Consultants for resolution through the EIA / approval

processes

The Contractor will be required to set up operational and monitoring procedures to ensure that all

environmental requirements are met.

7.2 Specific Measures

The following specific measures must be adopted to reduce pollution and turbidity to the absolute minimum.

Grading of the sand selected for reclaim and sandbank extension shall match that of the existing

sandbank as closely as possible. The material shall be free of clay, organic matter or other detritus.

Pumping shall be controllable in rate so that it can be slowed if turbidity levels rise. It is expected

that pumping can be maximized over both high and low tide periods, but may have to be reduced as

tidal flows in both directions increase. In particular turbidity during tidal flows away from the

sandbank and towards the new basin must be strictly controlled to prevent sand flowing back into

the newly dredged areas.

Floating containment curtains extending well into the water will be required to restrict movement of

the more turbid water until it has settled.

TRANSNET SOC LTD


PORT OF DURBAN



Page | 5

8.0 RISK ASSESSMENTS

Risk assessments will be carried out on all aspects of the work as defined in more detail in Method Statement 1370 –

MS – 003.

9.0 PROGRAMME

Suitable programming will be required for all aspects of the work as defined in more detail in Method Statement

1370 – MS – 003.

10.0 QA & QC

Suitable QA & QC procedures will be required for all aspects of the work as defined in more detail in Method

Statement 1370 – MS – 003.

11.0 HEALTH AND SAFETY

The Contractor will be responsible for the implementation of a comprehensive Health and Safety

programme

12.0 SPECIFICATIONS

As part of the design premise, ZAA will define all General Specifications and Codes of Practice for

reclamation and extension

Additional detailed Specifications will be provided where necessary or as a result of Field

Engineering Queries (FEQ)

13.0 DRAWINGS

ZAA will produce all necessary AFC Drawings

The Contractor will produce survey data and drawings of initial, interim and final stages of the

reclaim material placement.

14.0 RESOURCES AND EQUIPMENT

The Contractor will be responsible for the provision, establishment, operation, maintenance, and

disestablishment of suitable and reliable equipment for dredging, transport, placing and testing.

The contractor will further be responsible for any other equipment required for the placing of

reclaim material, as well as for management, scheduling, staff, sub‐contractors, power and fuels,

interfacing with Port Operations and managing vessel traffic.

15.0 RECORDS

The Contractor will be responsible for producing all ‘As built’ survey drawings

The Contractor shall maintain all QA / QC records

TRANSNET SOC LTD


PORT OF DURBAN


ZAA 1370 | MS | 016 Rev 00 Annexures September 2012

Page | 1

ANNEXURES

TRANSNET SOC LTD


PORT OF DURBAN


ZAA 1370 | MS | 016 Rev 00 Annexures September 2012

Page | 2

ANNEXURE 1 – DRAWINGS

1370‐DWG‐1700 Rev P02 – Berth 203 to 205 Deepening – Dredging ‐ General Layout Option 3G

1370‐DWG‐1710 Rev P00 – Berth 203 to 205 Deepening – Dredging – Mooring Basin Layout Option 3G

1370‐DWG‐1711 Rev P00 – Berth 203 to 205 Deepening – Dredging – Sections Option 3G

29°52'S

31°02'E

THE POINT

E

S

P

LA

N

A

D

E

C

H

A

N

N

E

L

2

0

5

2'

31°E

2' 3' 4'

52'

S

A

N

D

B

A

N

K

P

I

E

R

N

o

1

P

IE

R

N

o

2

M

U

L

T

I

-

P

U

R

P

O

S

E

T

E

R

M

I

N

A

L

2

0

4

2

0

3

T

J

E

T

T

Y

1'

5' 6' 7' 8'

31°E

2' 3' 4'

1'

5' 6' 7' 8'

L

O

T

1

0

1370-DWG-1700- P02

EMAIL : [email protected]

PO Box 26546

Tel: +2721 791 9100

HOUT BAY 7872 HOUT BAY 7806

Fax: +2721 790 4470

31 Melkhout Crescent

www.zaaepna.com

1370-DWG-1710 REV P00


PO Box 26546

Tel: +2721 791 9100


Fax: +2721 790 4470


www.zaaepna.com

1370-DWG-1711 REV P00


PO Box 26546

Tel: +2721 791 9100


Fax: +2721 790 4470


www.zaaepna.com

Documents

TRANSNET SOC LTD 3) FOR THE 203 and 205 L...TRANSNET SOC LTD FEASIBILITY STUDY ... METHOD STATEMENT: ... Determined the extent of dredging at the toe of the existing sandbank, the