(I) Document Status

Details of Revision:

Revision	Rev. Date	Sections	Amendment Source and/or Details
A	30 Aug 2013	All	Issued for Approval
B	23 Sep 2013	All	Revised for Approval
C	24 Sep 2013	4, 5	4(i) – Updated table 2 5 – updated general notes of installation measures
D	8 Oct 2013	2 (vi), 4 (ii), Appendix C	2(vi) - Only generator will be use on the vessel. 4(ii) – update 4(ii) clause App. C – add typical drawing for acoustic decoupling measures

Status of Page Revision:

Rev. ð Section Ê

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

1

X

X

2

X

X

x

3

X

X

4

X

X

X

x

5

X

X

X

Rev. ð SectionÊ

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

Appendix A

X

X

Appendix B

X

X

Appendix C

X

(II) PROJECT DETAILS

Contract no. : HY/2012/08

Project Title : Tuen Mun – Chek Lap Kok Link, Northern Connection Sub-Sea

Tunnel Section

Contract Period : From 31^st July 2013 to 25^th October 2018

The Client : Government of Hong Kong Special Administration Region –

Highways Department

The Supervising Officer : AECOM Asia Company Limited

The Main Contractor : Dragages - Bouygues Joint Venture

Nature of Work : The design and/or construction for the section of TM-CLKL between Tuen Mun Area 40 and the HKBCF, include the following scope of work:

(i) Design and construction of sub-sea TBM tunnels (two tubes with cross passages) across the Urmston Road, connecting Tuen Mun Area 40 and HKBCF, of approximately 4 km in length with dual 2-lane carriageway (Figure 1);

(ii) Design and construction of cut-and-cover tunnels (two boxes with cross passages) at both the southern landfall (Figure 3) and the northern landfall (Figure 2) for construction of approach roads to the sub-sea TBM tunnels, of approximately 1.5km in length;

(iii) Construction of northern landfall (Figure 2) reclamation of approximately 16.5 hectares and about 2.0km long seawalls;

(iv) Design and construction of ventilation buildings at the southern and northern landfalls;

(v) Design and construction of at-grade roads at the southern and northern landfalls;

(vi) Construction of extension of the existing 4-cell box culvert adjacent to RTT;

(vii) Provision of a temporary pontoon for the affected existing Government berths at RTT;

(viii) Design and construction for modification of a section of vertical seawall of approximately 220m in length at the southern landfall (Figure 3) to sloping seawall;

(ix) Design and construction of associated civil, structural, building, geotechnical, marine, environmental protection, drainage and sewerage, waterworks and utility works;

(x) Design and construction of advance SEM provisions to facilitate installation of E&M, TCSS and other utilities including tunnel ventilation, tunnel lighting, tunnel fire services, mechanical ventilation & air- conditioning, high voltage power supply, low voltage power supply, fire services, plumbing & drainage, central monitoring & control system and implementation of an EM&A programme for the works under this Contract.

(III) SITE LAYOUT PLAN

Figure 1 – HY/2012/08 Project

Figure 2 – Northern Landfall

Figure 3 – Southern Landfall

(IV) TABLE OF CONTENTS

(I) Document StatuS ii

(II) PROJECT DETAILS iv

(III) SITE LAYOUT PLAN vi

(IV) Table Of Contents ix

1. Introduction.. 1

2. MArine Construction Noise Source.. 1

3. Proposed Acoustic Decoupling Measures. 3

4. Implementation of Acoustic Decoupling Measures. 3

5. General Notes on Installation Measures. 4

AppendiCES

Appendix A Photos of Noisy Equipment and proposed working vessels

Appendix B ISolation Material PRoduct Literature

Appendix C typical set up of the acoustic decoupling measures for the generator

1. Introduction

(i) The Tuen Mun – Chek Lap Kong Link serves to connect Tuen Mun with the Chek Lap Kok and the Hong Kong - Zhuhai - Macau Bridge.

(ii) Highways Department has awarded this Contract to Dragages – Bouygues Joint Venture. Project details are given in Section II above. The Contract scope is depicted in Figures 1, 2 and 3.

(iii) This plan is prepared in accordance with Condition 2.5 of the Environmental Permit (EP-354/2009/A), which requires the Permit Holder to submit to the Director of Environmental Protection the design and implementation of acoustic decoupling measures applied during bored piling, dredging and reclamation works.

2. MArine Construction Noise Source

(i) Under the design of the HY/2012/08 Contract, there will be no marine bored piling works and may have limited sheet piling works. The primary marine works will be dredging and reclamation to form the Northern Landfall (Figure 2). The Southern Landfall (Figure 3) will be reclaimed by others and the sub-sea tunnel (Figure 1) will be constructed by tunnel boring machines (TBM), in rocks underneath the marine environment.

(ii) The noise sources from marine works at the Northern Landfall (Figure 2), during the construction phase, will mainly comprise of the following activities:

a. Installation of silt curtain;

b. Installation of a temporary seawall, which may be a steel structure, concrete block structure or rock fill. Sheet piling or similar methods may be used;

c. Dredging at the base of load bearing structures and other engineering elements, such as the seawall;

d. Laying geotextile

e. Installation of band drain;

f. Sand and reclamation filling.

(iii) According to Section 8.11.9.29 of the approved EIA Report (Agreement No. CE 52/2007 (HY)), the use of high-frequency sounds by Chinese White Dolphins make them less vulnerable to the effects of dredgers and large vessels, which generally produce very low frequency noises of less than a few kilohertz. These types of vessels are thus not considered to be a significant source of acoustic disturbance and will not be considered as sources of noise and vibration for the implementation of acoustic decoupling measures.

(iv) According to Section 8.14.4.13 of the approved EIA Report (Agreement No. CE 52/2007 (HY)), construction equipment can be noisy and, when such pieces of equipment are used on the water or in coastal waters, some of the sound may be transmitted into water and affect small cetaceans as noise pollution. Air compressors and other noisy equipment that must be mounted on steel piling barge should be acoustically de-coupled to the greatest extent feasible. Section 8.14.4.13 of the EIA Report suggests the use of rubber tires or air-filled tires to de-couple noise (i.e. wheel mounted air compressors or generators are de-couples from the deck).

(v) It is envisaged that there will be 6 types of working vessels working in the Northern Landfall dredging and reclamation area. Some of them are support vessels and will not carry separate noisy equipment. Not all of the noisy equipment will be operated at any one time.

(vi) The noisy equipment allocated on the working vessels is listed in Table 1. Only generator will be mounted on the vessels, together with acoustic decoupling measures. No other noisy equipment will be use on board. The photos of the noisy equipment are shown in Appendix A. The list will be updated regularly and communicated to the SOR, ETL and IEC/ENPO.

Table 1: Vessel and Noisy Equipment Inventory

Working Vessels	Noisy Equipment on Working Vessels	Expected No of generators
2400T Derrick Barge x 8	Generator, Silenced, 75dB (A) at 7m (Diesel, 35.81kW, 1.5 Tons. Approx.) only installed in 2 nos. of barge	2
850hp Tug Boat x 4	None	0
1000m^3 Split Hopper Barge x 7	Generator, Silenced, 75dB (A) at 7m (Diesel, 35.81kW, 1.5 Tons. Approx.) only installed in 5 nos. of barge	5
Flat Top Barge x 1	Generator, Silenced, 75dB (A) at 7m (Diesel, 35.81kW, 1.5 Tons. Approx.) x 1/barge	1
Grab Dredger x 2	Generator, Silenced, 75dB (A) at 7m (Diesel, 35.81kW, 1.5 Tons. Approx.) x 2/dredger	4
Motor Sampan	No Noisy Equipment, for transportation only	0

3. Proposed Acoustic Decoupling Measures

(i) The same noise isolation pad previously approved in other Hong Kong – Zhuhai – Macau Bridge (HZMB) projects (e.g. Link Road Contracts HY/2011/03, HY/2011/09 and HY/2012/07) is proposed to be used for this Contract. This product was originally developed and marketed as noise dampening underlays for building construction. Product literature of the isolation material is given in Appendix B.

(ii) If sheet piling is to be carried out, isolation pads shall be fitted between the vibrator clamp and the sheet pile, such that the path from noisy equipment through the sheet pile to the marine environment is broken.

(iii) The typical set up of the acoustic decoupling measures for the generator and the sheet pile vibrator are shown in Appendix C.

4. Implementation of Acoustic Decoupling Measures

(i) The dimensions of the proposed isolation pad for the noisy equipment are given in Table 2.

Table 2: Vessel and Noisy Equipment Inventory: Footprint Area of Isolation Padding

Proposed Working Vessel	Noisy Equipment Identified on Working Vessel	Envisaged Dimension of Proposed Isolation Pad (LxWxH) Each
2,400T Derrick Barge x 8	Generator (Diesel)	2m x 1m x 30mm approx.
850hp Tug Boat x 4	None	N.A.
1,000m^3 Split Hopper Barge x 7	Generator (Diesel)	2m x 1m x 30mm approx.
Flat Top Barge x 1	Generator (Diesel)	2m x 1m x 30mm approx.
Grab Dredger x 2	Generator (Diesel)	2m x 1m x 30mm each (approx.)
Motor Sampan	None	N.A.

(ii) Only generator will be mounted on the vessels, together with acoustic decoupling measures. No other noisy equipment will be use on board.

(iii) Noisy equipment will be fixed on noise decoupling pads instead of being mounted directly on the deck. The Contractor will ensure the foundation of the equipment is flat and level prior to installation. Adequate clearance all around the noisy equipment will be kept to avoid vibration transmitted to other materials and machinery.

(iv) Those noisy equipments, such as engines, which are welded directly onto the deck of vessel, should provide other mitigating measures such as alternative work schedule to minimize the vibration transmission to the sea.

5. General Notes on Installation Measures

(i) To forbid direct vibration transmission, adequate plinth clearance shall be kept all around.

(ii) Close all panels or doors of generators when in use.

(iii) To avoid noise breakout and the undesirable sound paths through gaps, the foundation where the equipment to be placed shall be flat and level.

(iv) To further eliminated the sound generation from noisy parts, flexible bellows silencers, mufflers shall be applied when necessary.

END OF CONTENT

Appendix A - Photos of Noisy Equipment and Proposed working vessels

Noisy Equipment

Generator on vessel board

working vessels

2400T Derrick Barge	850hp Tug Boat

1000m3 Split Hopper Barge	Flat Top Barge

Grab Dredger	Motor Sampan

Appendix B - ISOLATION MATERIAL PRODUCT LITERATURE

Appendix C - typical set up of the acoustic decoupling measures for the generator