Figures No.	NSR Ref.	NSR	No. of Floor	Shortest Slant Distance (m)	Description
5.1a/5.3a	SR1	8, Ha Ling Pei	3	235	Residential
SR2	7, Wong Ka Wai	3	119	Residential
SR3	Village House	3	256	Residential
SR4	8, Lung Tseng Tau	3	56	Residential
SR5	Village House	3	168	Residential
5.1b	SR6	41, Shek Lau Po	3	246	Residential
SR7	Village House	3	198	Residential
SR8	1, Shek Mun Kap	3	230	Residential
5.1c	SR9	AFCD Staff Quarters	1	156	Residential

5.1d	SR10	74, Leyburn Villas	2	298	Residential
5.1e	SR11	12, Cheung Sha Sheung Tsuen	3	277	Residential
SR12	32, Cheung Sha Sheung Tsuen	3	266	Residential
SR13	31B, South Lantau Road	2	35	Residential
SR14	Village House	2	153	Residential
SR15	YWCA Youth Camp	1	55	Residential
5.1f	SR16	Block 1, Acacia Villa	3	161	Residential
SR17	37, South Lantau Road	3	234	Residential
SR18	39, South Lantau Road	3	289	Residential
5.1g	SR19	Block 17, Butterfly Crest	3	#	Residential
Additional Sensitive Receivers in Tung Chung Valley
5.3a	SR1A	10, Ha Ling Pei	3	273	Residential
SR1B	8, Ha Ling Pei	3	256	Residential
SR1C	7, Ha Ling Pei	3	215	Residential
SR2A	14, Wong Ka Wai	3	165	Residential
SR2B	9, Wong Ka Wai	3	132	Residential
SR2C	7, Wong Ka Wai	3	99	Residential
SR2D	3A, Wong Ka Wai	3	83	Residential
SR4A	10A, Lung Tseng Tau	3	60	Residential
SR4B	7, Lung Tseng Tau	3	45	Residential
SR4C	13, Lung Tseng Tau	3	55	Residential
SR4D	28, Lung Tseng Tau	3	34	Residential
Future Sensitive Receivers in Cheung Sha⁽¹⁾
5.1f	CS1	Cheung Sha future sale site	2	35⁽²⁾	Residential
CS2	Cheung Sha future sale site	2	32⁽²⁾	Residential
CS3	Cheung Sha future sale site	2	56⁽²⁾	Residential
CS4	Cheung Sha future sale site	2	53⁽²⁾	Residential
CS5	Cheung Sha future sale site	2	25⁽²⁾	Residential
CS6	Cheung Sha future sale site	2	20⁽²⁾	Residential
CS7	Cheung Sha future sale site	2	20⁽²⁾	Residential
CS8	Cheung Sha future sale site	2	25⁽²⁾	Residential
CS9	Cheung Sha future sale site	2	29⁽²⁾	Residential
CS10	Cheung Sha future sale site	2	33⁽²⁾	Residential
CS11	Cheung Sha future sale site	2	50⁽²⁾	Residential
CS12	Cheung Sha future sale site	2	22⁽²⁾	Residential
CS13	Cheung Sha future sale site	2	42⁽²⁾	Residential

5.3.1.1 The construction equipment for each stage of the project has been determined and the sound power level (SWL) of each piece of equipment is based upon the Technical Memorandum on Noise From Construction Work Other Than Percussive Piling and BS5228 when the SWL are not listed in the Technical Memorandum. No percussive piling is anticipated for the Project.

5.3.1.2 The construction activities for the Project can be divided into four broad areas, namely roadworks and bridgeworks for the main alignment, slope stabilisation works and slope remediation works for the obsolete section of the existing Tung Chung Road. The key construction activities within these broad activities will include:

(i) Roadworks - earthworks

(including utility works) - retaining wall construction (required for all

areas not on structure); and

- pavement construction.

(ii) Bridgeworks: - foundation construction; and

- deck construction.

(iii) Slope Stabilisation - soil nailing/rock dowelling; and

- equipment transportation.

(iv) Slope Remediation - earthworks; and

- slope nailing.

(v) Noise Mitigation - foundation construction; and

- erection.

5.3.1.3 The individual pieces of equipment required for each of these stages have been highlighted in Section 2. The construction plant has been further divided into working scenarios for each of the broad construction activities as detailed in Table 5.2 below:

Table 5.2: Equipment Scenarios

Main Activity	Sub-Activity	Equipment Scenario	Scenario Reference
Roadworks	Earthworks⁽¹⁾	Scenario 1 - Rock/earth excavation	E1
		Scenario 2 - Removal /spreading of earth/rock	E2
		Scenario 3 - Forming of earthworks.	E3
	Retaining Wall Construction	Scenario 1 - Foundation works	R1
		Scenario 2 - Piling	R2
		Scenario 3 - Formwork/concreting.	R3
		Scenario 4 - Backfilling Works	R4
	Pavement Construction ⁽¹⁾	Scenario 1 - Preparation of Roadbase	P1
		Scenario 2 - Laying of Surface Material	P2
		Scenario 3 - Road Marking	P3
Bridgeworks	Foundation Construction	Scenario 1 - Excavation	F1
		Scenario 2 - Piling	F2
		Scenario 3 - Formwork	F3
		Scenario 4 - Concreting	F4
	Deck Construction	Scenario 1 - Formworks	D1
		Scenario 2 - Concreting	D2
		Scenario 3 - Deck elevation	D3
Slope⁽²⁾ Stabilisation	Rock Dowelling	Scenario 1 – Rock dowelling	SS1
Slope⁽²⁾ Stabilisation	Equipment Transportation	Scenario 1 – Delivery by helicopter	SS2
Slope ⁽²⁾ Remediation	Earthworks	Scenario 1 – Earthworks	SR1
Slope ⁽²⁾ Remediation	Slope Nailing	Scenario 1 – Slope Nailing	SR2
Noise Mitigation	Foundations and Erection	Scenario 1 – Foundation Works	NB1
		Scenario 2 – Piling	NB2
		Scenario 3 – Formwork/Concreting	NB3
		Scenario 4 – Backfilling Works	NB4
		Scenario 5 - Erection	NB5

Notes (1): Includes minor works associated with utilities.

(2): No drainage works are required for the slope stabilisation works. Noise associated with the drainage and shotcreting works for the remediation of slopes on the existing Tung Chung Road are considered to be minor but covered in Table 5.8d.

5.3.1.4 The equipment included in each of these scenarios, together with the appropriate sound power levels are provided in Tables 5.3 to 5.7 below for roadworks, bridge works, slope stabilisation works, slope remediation works and noise mitigation works respectively. As noted, in Section 2.7.2, the equipment lists have been confirmed by the Project Proponent as being practical for completing the works.

Table 5.3: Typical Equipment Requirement for Road Construction

CNP Equipment Code	Equipment Scenario	Sound Power Level (SWL) in dB(A)	Number of Equipment	Total Sound Power Level (SWL) in dB(A)
Earthworks
Scenario E1	Excavation of earth / rock and removal
028	Breaker	122	2	125.9
067	Dump Truck	117	1
081	Excavator	112	1
282	Water Pump (Petrol)	103	1
Scenario E2	Spreading of earth / rock
030	Bulldozer	115	1	119.5
067	Dump Truck	117	1
204	Scraper	109	1

Scenario E3	Forming of earthworks
030	Bulldozer	115	1	120.7
104	Grader	113	1
067	Dump Truck	117	1
186	Roller Vibratory	108	1
050	Compactor	105	1
169	Power Rammer (Petrol)	108	1
Retaining wall construction
Scenario R1	Foundation works
028	Breaker	122	2	125.9
067	Dump Truck	117	1
081	Excavator	112	1
282	Water Pump (Petrol)	103	1
Scenario R2⁽¹⁾	Piling
164	Piling Rig	115	1	116.9
282	Water Pump	103	1
141	Lorry	112	1
165	Piling, large diameter bored, oscillator *	115	1
Scenario R3	Formwork / concreting
044	Concrete Lorry Mixer	109	1	117.9
170	Poker	113	1
101	Generator	108	1
201	Saw, circular	108	1
282	Water pump	103	1
043	Chipper	112	1
066	Dumper	106	1


CNP Equipment Code	Equipment Scenario	Sound Power Level (SWL) in dB(A)	Number of Equipment	Total Sound Power Level (SWL) in dB(A)
Scenario R4	Backfilling works
050	Compactor Vibratory	105	1	117.8
067	Dump Truck	117	1
186	Roller Vibratory	108	1
	Pavement Construction
Scenario P1	Preparation of Roadbase
186	Vibratory roller	108	1	118.6
067	Dump truck	117	1
081	Excavator	112	1
Scenario P2	Laying of Surface Material
004	Asphalt paver	109	1	119.0
185	Road roller	108	1
067	Dump Truck	117	1
186	Vibratory roller	108	1
044	Concrete Lorry Mixer	109	1
Scenario P3	Road Marking
161	Paint line marker	90	1	115.0
203	Saw	115	1	115.0

* The piling oscillator will be required to be used with the piling rig (CNP 164). However, as these pieces of equipment will be used alternately and never concurrently, the total SWL has been based upon the SWL of only one piece of equipment (ie one SWL of 115 only).

(1) The equipment which will be used for the detailed ground investigation will be similar to that required for the bored piling. However, the bored piling rig will be noisier than the rig used for the ground investigation.

Table 5.4: Typical Equipment Requirement for Bridge Construction

CNP Equipment Code	Equipment Scenario	Sound Power Level (SWL) in dB(A)	Number of Equipment	Total Sound Power Level (SWL) in dB(A)
Deck Construction
Scenario D1	Formwork
021	Bar Bender and cutter	90	1	119.8
171	Planer	117	1
101	Generator	108	1
201	Saw	108	1
043	Chipper, hand-held	112	1
141	Lorry	112	1
Scenario D2	Concreting
044	Concrete lorry mixer	109	1	115.5
047	Concrete pump	109	1
170	Poker	113	1
Scenario D3	Elevation
048	Crane	112	1	112.0

Foundation/Pier Construction
Scenario F1	Excavation
027	Breaker	122	2	125.9
067	Dump truck	117	1
081	Excavator	112	1
282	Water Pump	103	1
Scenario F2	Piling
164	Piling Rig	115	1	119.1
283	Water Pump	85	1
067	Dump Truck	117	1
165	Piling, large diameter bored, oscillator*	115	1
Scenario F3	Formwork
021	Bar Bender	90	1	118.0
171	Planer	117	1
101	Generator	108	1
201	Saw	108	1
Scenario F4	Concreting
047	Concrete pump	109	1	115.5
044	Concrete lorry mixer	109	1
170	Poker	113	1

Table 5.5 Typical Equipment Requirement for Slope Stabilisation Works

CNP Equipment Code	Equipment Scenario	Sound Power Level (SWL) in dB(A)	Number of Equipment	Total Sound Power Level (SWL) in dB(A)
Rock Dowelling
Scenario SS1	Rock Dowelling
183	Rock Drill, hand held	116	1	116.3
003	Compressor	104	1	116.3
Equipment Transportation
Scenario SS2	Delivery by Helicopter⁽¹⁾

(1) The assessment of helicopter noise has been based upon the L_max for typical helicopter models and not the SWL.

Table 5.6 Typical Equipment Requirement for Slope Remediation Works

CNP Equipment Code	Equipment Scenario	Sound Power Level (SWL) in dB(A)	Number of Equipment	Total Sound Power Level (SWL) in dB(A)
Slope Remediation Earthworks
Scenario SR1	Earthworks
081	Excavator	112	1	118.2
067	Dump Truck	117	1	118.2
Slope Nailing
Scenario SR2	Slope Nailing
183	Rock Drill, hand held	116	1	116.3
003	Compressor	104	1	116.3

Table 5.7 Typical Equipment Requirement for the Construction of Permanent Noise Barrier in Tung Chung Valley

CNP Equipment Code	Equipment Scenario	Sound Power Level (SWL) in dB(A)	Number of Equipment	Total Sound Power Level (SWL) in dB(A)
Noise Barrier Construction
Scenario NB1	Foundation works
Scenario NB1A
026	Breaker, Hand Held	114	1	114.3
002	Air compressor	102	1
Scenario NB1B
081	Excavator	112	1	112.5
282	Water Pump	103	1
Scenario NB1C
141	Lorry with grab#	112	1	112.0
Scenario NB2	Piling
-	Mini Piling Rig*	113	1 1	113.4
282	Water Pump	103	1 1
Scenario NB3	Formwork / concreting
044	Concrete Lorry Mixer	109	1	114.8
170	Poker	113	1
282	Water pump	103	1
Scenario NB4	Backfilling works
Scenario NB4A
050	Compactor Vibratory	105	1	105.0
Scenario NB4B
141	Lorry with grab#	112	1	112.0

Scenario NB5	Erection
Scenario NB5A
141	Lorry with grab#	112	1	112.0
Scenario NB5B
048	Crane	112	1	112.0

CNP

Equipment Code

Equipment Scenario

Sound Power

Level (SWL) in dB(A)

Number of Equipment

Total Sound Power Level (SWL) in dB(A)

Noise Barrier Construction

Scenario NB1

Foundation works

Scenario NB1A

026

Breaker, Hand Held

114

114.3

002

Air compressor

102

Scenario NB1B

081

Excavator

112

112.5

282

Water Pump

103

Scenario NB1C

141

Lorry with grab#

112

112.0

Scenario NB2

Piling

Mini Piling Rig*

113

113.4

282

Water Pump

103

Scenario NB3

Formwork / concreting

044

Concrete Lorry Mixer

109

114.8

170

Poker

113

282

Water pump

103

Scenario NB4

Backfilling works

Scenario NB4A

050

Compactor Vibratory

105

105.0

Scenario NB4B

141

Lorry with grab#

112

112.0

Scenario NB5

Erection

Scenario NB5A

141

Lorry with grab#

112

112.0

Scenario NB5B

048

Crane

112

112.0

* See Table C.10, item 6 of BS 5228 for SWL

# Lorry (CNP 141) is assumed for the purposes of the noise assessment.

5.3.2 Predicted Traffic Flows

5.3.2.1 Predicted traffic flows used in the operational noise assessment have been discussed in Section 2.8 of this report. Transport Department have approved the traffic figures for use in the EIA and their approval is presented in Appendix G.

5.4 Construction Noise Impact Assessment

5.4.1 Assessment Methodology

5.4.1.1 The assessment of the proposed alignment has comprised an evaluation of the construction noise impacts at representative sensitive receivers along its length based upon the full range of construction activity scenarios detailed above. The construction noise at the NSRs has been assessed in accordance with the methodology of the Technical Memorandum on Noise from Construction Work Other than Percussive Piling. The noise impact from the use of a helicopter to deliver slope stabilisation equipment has also been assessed. While the assessment of construction noise has been based upon non-restricted periods, this does not preclude the Contractor from working in restricted periods should this be required. However, any work in restricted periods will be subject to the Contractor obtaining a valid Construction Noise Permit under the Noise Control Ordinance as detailed in Section 3.3.2. It is likely that working up to 11.00pm will be required and further assessment of this period is presented in Section 5.4.3.12 below.

5.4.1.2 Potential cumulative impacts associated with the construction of the development in Tung Chung Valley are assessed in Section 12. There are no other cumulative impacts from other contemporary projects in the vicinity.

5.4.1.3 Construction activities on site will involve the use of heavy machinery and as detailed in Section 5.3, an indicative schedule of key equipment to be used, activities to be carried out and duration of each segment of the works has been identified. Based upon the number and type of heavy plant to be employed in the construction works, noise levels generated will probably be high and impacts are a key issue.

5.4.2 Assessment Findings

5.4.2.1 The maximum noise levels at the NSRs during the construction phase of the alignment without noise mitigation measures applied are shown below in Tables 5.8a and 5.8b for the road earthworks and bridge works respectively, Tables 5.8c and 5.8d for the slope stabilisation and slope remediation respectively and Table 5.8e for the permanent noise barrier construction. The detailed modelling result is provide in Appendix F and a summary of the maximum unmitigated levels at each NSR is provided in Figures 5.2a to 5.2e.

Table 5.8a Maximum Noise Levels (dB(A)) during Road Construction without Noise Mitigation

Sensitive Receiver	Slant Distance (m)	Noise Level without Mitigation, dB(A)
	(EW+PC/RW)⁽¹⁾	Earth Works			Retaining Wall				Pavement Construction
	Scenario	E1	E2	E3	R1	R2⁽²⁾	R3	R4	P1	P2	P3
	SWL	125.9	119.5	120.7	125.9	116.9	117.9	117.8	118.6	119.0	115.0
SR1	235/325	73	67	68	71	62	63	63	66	67	63
SR2	114/238	80	73	75	73	64	65	65	72	73	69
SR3	256/425	73	66	68	68	59	60	60	65	66	62
SR4	56/162	86	80	81	77	68	69	69	79	79	75
SR5	162/211	77	70	72	74	65	66	66	69	70	66
SR6	244/248	73	67	68	73	64	65	65	66	66	62
SR7	202/206	75	68	70	75	66	67	66	67	68	64
SR8	229/241	74	67	68	73	64	65	65	66	67	63
SR9	156/161	77	71	72	77	68	69	69	70	70	66
SR10	276/271	72	66	67	72	63	64	64	65	65	61
SR11	267/272	72	66	67	72	63	64	64	65	65	61
SR12	263/252	72	66	67	73	64	65	65	65	66	62
SR13	32/32	91	84	86	91	82	83	83	83	84	80
SR14	151/145	77	71	72	78	69	70	70	70	70	66
SR15	55/96	86	80	81	81	72	73	73	79	79	75
SR16	166/164	76	70	71	77	68	69	68	69	70	66
SR17	240/234	73	67	68	73	65	66	65	66	66	62
SR18	291/291	72	65	66	72	63	64	63	64	65	61

76	Noise Level at the sensitive receiver exceeds relevant criteria of 75dB(A) for domestic premises

(1): The first distance quoted relates to both earth works and pavement construction and the second distance in the column is from the NSR to the nearest retaining wall works. Locations of retaining walls are shown in Figures 5.1a to f.

(2): Equipment for the piling activities assumed to be noisier than that required for the detailed ground investigation. However, based upon a worst case scenario, predicted noise levels for scenario R2 could be used to represent GI works.

Table 5.8b Maximum Noise Levels (dB(A)) at NSRs during Bridge Construction without Noise Mitigation

Sensitive Receiver*		Slant Distance (m)	Noise Level without Mitigation, dB(A)
		Slant Distance (m)	Deck Construction			Foundation Construction
		Scenario	D1	D2	D3	F1	F2	F3	F4
		SWL	119.8	115.5	112.0	125.9	119.1	118.0	115.5
SR9		159	71	67	63	77	70	69	67
SR10		277	66	62	58	72	65	64	62
SR11		323	65	60	57	71	64	63	60
SR12		295	65	61	58	71	65	64	61
SR13		231	67	63	60	74	67	66	63
SR14		206	68	64	61	75	68	67	64
SR15		218	68	64	60	74	67	66	64
SR16		375	63	59	56	69	63	62	59
SR17		460	62	57	54	68	61	60	57
SR18		501	61	57	53	67	60	59	57

76	Noise Level at the sensitive receiver exceeds relevant criteria of 75dB(A) for domestic premises

* The distance between the SR1 to SR9, SR19 and the construction work is more than 500 metres, as such noise levels would not exceed the relevant noise criteria.

Table 5.8c Maximum Noise Levels (dB(A)) at NSRs during Slope Stabilisation Works without Noise Mitigation

Sensitive Receiver		Slant Distance (m)	Noise Level without Mitigation, dB(A)
		Scenario	Rock Dowelling (SS1)
		Total SWL	116.3
SR1		325	61
SR2		238	64
SR3		425	59
SR4		162	67
SR5		211	65
SR6		248	63
SR7		206	65
SR8		241	64
SR9		161	67
SR10		271	63
SR11		272	63
SR12		252	63
SR13		380	60
SR14		145	68
SR15		96	72
SR16		164	67
SR17		234	64
SR18		291	62

76	Noise Level at the sensitive receiver exceeds relevant criteria of 75dB(A) for domestic premises.

* Noise from transport of equipment by helicopter assessed below

Table 5.8d Maximum Noise Levels (dB(A)) at NSRs during Slope Remediation without Noise Mitigation

Sensitive Receiver*	Slant Distance (m)	Noise Level with Mitigation, dB(A)
	Slant Distance (m)	Earthwork	Soil Nailing
	Scenario	SR1	SR2
	SWL	118.2	116.3
SR19	90	74	72

Note: * SR1 to SR18 located near the improved Tung Chung Road, and will not affected by the slope remediation work on the obsolete section of the existing Tung Chung Road. (see Figures 2.12 and 2.13).

** Drainage works and shotcreting works associated with the slope remediation works would involve a concrete pump (CNP047) and a concrete mixer (CNP046) with a combined SWL of 109 dB(A). Based upon the fact that no adverse impacts have been predicted for the above noisier scenarios SR1 and SR2, no impacts from the drainage works are expected.

Table 5.8e Maximum Noise Levels (dB(A)) during Construction of Permanent Noise Barrier in Tung Chung Valley without Noise Mitigation

Sensitive Receiver	Slant Distance (m)	Noise Level without Mitigation, dB(A)
	Slant Distance (m)	Construction of Noise Barrier
	Scenario	NB1A	NB1B	NB1C	NB2	NB3	NB4A	NB4B	NB5A	NB5B
	SWL	114.3	112.5	112.0	113.4	114.8	105.0	112.0	112.0	112.0
SR1A	200	63	61	61	62	64	54	61	61	61
SR1B	179	64	62	62	63	65	55	62	62	62
SR1	153	66	64	63	65	66	56	63	63	63
SR1C	149	66	64	64	65	66	57	64	64	64
SR2A	96	70	68	67	69	70	60	67	67	67
SR2B	60	74	72	71	73	74	64	71	71	71
SR2	40	77	75	75	76	78	68	75	75	75
SR2C	21	83	81	81	82	83	74	81	81	81
SR2D	25	81	80	79	80	82	72	79	79	79
SR3	242	62	60	59	61	62	52	59	59	59
SR4A	50	75	74	73	74	76	66	73	73	73
SR4	48	76	74	73	75	76	66	73	73	73
SR4B	39	77	76	75	77	78	68	75	75	75
SR4C	46	76	74	74	75	77	67	74	74	74
SR4D	25	81	80	79	80	82	72	79	79	79
SR5	168	65	63	62	64	65	55	62	62	62

Note: * SR6 to SR19 are located more than 300 meters away from the barrier construction works and thus will not be affected by these works.

76	Noise Level at the sensitive receiver exceeds relevant criteria of 75dB(A) for domestic premises

Transportation of Slope Stabilisation Equipment by Helicopter

5.4.2.2 As highlighted previously, some equipment required high up the hills may need to be transported by helicopter. The areas where the slope stabilisation works will be required are shown by the limit of slope stabilisation in the figures in Section 2. Based upon the works, there is the potential for short term noise impacts on the local residents.

5.4.2.3 The TMEIA specifies a maximum level for helicopter noise at sensitive receivers which is 85 L_max dB(A). However, if the helicopter is considered to be a piece of construction equipment then the 75 dB(A) at the sensitive receivers should be met. Thus, in order to provide a full assessment, comparison to both these standards has been made.

5.4.2.4 Based upon two common helicopter types used in Hong Kong, the L_max dB(A) of each are detailed in Table 5.9 as follows:

Table 5.9 L_max dB(A) of Common Helicopter Types in Hong Kong

Brand

Model

Users

Reference Height⁽¹⁾

L_maxdB(A) ⁽¹⁾

Sikorsky

S76

Government Flying Service, Private

244m (800 feet)

78dB(A)

Aerospatiale

(Eurocopter)

AS355

Private

153m (500 feet)

77dB(A)

Note (1): Source: UK Institute of Acoustics (IOA), Volume 14, Part 4 (1992) “Noise Levels of Helicopters Performing Elevated Pad Take-off and Landing Procedures”.

5.4.2.5 The impact of noise from the helicopter can be calculated at the facades of the representative NSRs in terms of maximum L_Amax using basic acoustic principles as follows:

At a specified distance, say D1, the Sound Pressure Level (Lp) should be

Lp(at D1) = Lw - distance attenuation (D1) ……(1)

where Lw is the Sound Power Level

Since the helicopter noise is a point source, then (1) can be converted:

Lp(at D1) = Lw - 20log(D1) ……(2)

At distance D2, then

Lp(at D2) = Lw - 20log (D2) ……(3)

Rearrange (2) and (3)

Lw=Lw, then,

Lp(at D1) + 20log (D1) = Lp (at D2) + 20 log(D2), and

Lp(at D2) = Lp(at D1) + 20log (D1) - 20log (D2), and

Lp(at D2) = Lp(at D1) + 20(log(D1/D2)) ……(4)

Equation (4) can be used to convert the reference noise level from the helicopter measurement to the noise level at a specified distance. The facade correction factor is then included.

5.4.2.6 The predicted noise levels in L_max dB(A) based on the two different helicopter types at a set of distances from noise sensitive receivers are shown in Table 5.10 below.

Table 5.10 Predicted Helicopter Noise (L_max dB(A))

Distance (metres)	Sikorsky S76		Aerospatiale AS355
	Reference Noise Level 78	Reference Distance, 244 m	Reference Noise Level 77	Reference Distance, 153 m
	Noise Level (non-building)	Noise Level (facade)	Noise Level (non-building)	Noise Level (facade)
10	106	109	101	104
20	100	103	95	98
30	96	99	91	94
40	94	97	89	92
50	92	95	87	90
60	90	93	85	88
70	89	92	84	87
80	88	91	83	86
90	87	90	82	85
100	86	89	81	84
110	85	88	80	83
120	84	87	79	82
130	83	86	78	81
140	83	86	78	81
150	82	85	77	80
160	82	85	77	80
170	81	84	76	79
180	81	84	76	79
190	80	83	75	78
200	80	83	75	78
210	79	82	74	77
220	79	82	74	77
230	79	82	73	76
240	78	81	73	76
250	78	81	73	76
260	77	80	72	75
270	77	80	72	75
280	77	80	72	75
290	76	79	71	74
300	76	79	71	74
310	76	79	71	74
320	76	79	71	74
330	75	78	70	73
340	75	78	70	73
350	75	78	70	73
360	75	78	70	73
370	74	77	69	72
380	74	77	69	72
390	74	77	69	72
400	74	77	69	72
410	73	76	68	71
420	73	76	68	71
430	73	76	68	71
440	73	76	68	71
450	73	76	68	71
460	72	75	67	70
470	72	75	67	70
480	72	75	67	70
490	72	75	67	70
500	72	75	67	70

5.4.2.7 In accordance with Hong Kong’s Civil Aviation Department requirements, helicopters must operate outside a 500ft (152 metres) ceiling from residential properties. This distance, will, therefore, be the shortest distance between the noise sensitive receivers and any helicopter noise. Based upon the results in Table 5.9, it can be seen that the maximum noise of both helicopter types would not exceed the 85dB(A) noise limit at this distance.

5.4.2.8 Based upon the testing and investigation, the approximate area for slope stabilisation works is shown in Section 2. The distance between slope stabilisation work and the nearest sensitive receivers is about 500 metres. According to the result shown in Table 5.10, the L_max for the helicopter, the Sikorsky S76 and Aerospatiale AS355, is 75 and 70 dB(A) at 500m respectively which is within the 85 dB(A) criteria. The noise at the sensitive receivers is also within the 75 dB(A) noise criteria if the helicopter is considered to be a piece of construction equipment.

5.4.2.9 The helicopter pick-up location will be located at the proposed Contractor’s works area which is shown in Figure 2.10. This area is 400 meters away from the nearest existing noise sensitive receivers. Based upon this distance and the levels provided in Table 5.10 above, the maximum noise level at the closest sensitive receiver would be 77 and 72 for the Sikorsky S76 and Aerospatiale helicopters respectively. Thus, the Sikorsky S76 helicopter would marginally exceed the noise criteria 75dB(A) if the helicopter remained on the works area for a period of 30 minutes.

5.4.2.10 It has been determined that in order to meet the 75 dB(A) standard, the operation of the helicopter at the pick-up location should be restricted to 60%, which equates to the helicopter operating for only 18 minutes in any half hour period at the pick-up point. This period is more than sufficient for the helicopter to remove or drop off equipment in this location and move away. In addition, the scenarios assessed are the worst case, with noise levels being lower with a quieter helicopter.

5.4.2.11 Thus, no unacceptable impacts are predicted from the use of the helicopter, as is the case for the slope stabilisation and slope remediation activities associated with the new road.

5.4.2.12 However, the results detailed above for road construction, bridge construction and noise barrier construction in Tung Chung Valley indicate that, the maximum noise levels at some of the NSRs will exceed the day time noise criteria of 75dB(A). Mitigation measures are, therefore, required to reduce the noise levels to meet the standards. Recommended mitigation measures are detailed in Section 5.4.3.

5.4.3 Construction Mitigation Measures

5.4.3.1 Based upon the anticipated construction scenarios for the main alignment, the maximum noise levels at the closest NSRs would exceed the 75dB(A) noise guideline for non restricted hours at residential properties during road construction and permanent noise barrier construction. Thus, the following noise mitigation measures should be implemented to reduce the construction noise to an acceptable level. The noise mitigation measures and the sound reduction estimated are based on current noise control technologies and BS5228 and have been confirmed by the Project Proponent as being practical.

5.4.3.2 Noise mitigation measures are recommended at SRs 2, 4, 5, 9, 13-16 during road construction and SR9 during bridge construction and SRs 2 and 4 in Tung Chung Valley during permanent noise barrier construction as detailed below in Tables 5.11 and 5.12 respectively.

Table 5.11: Recommended Mitigation Measures for the Noisy Equipment during Road Construction and Bridge Construction

Plant	Mitigation Measures*	Noise Reduction, dB(A)*	Reduction Assumed, dB(A)
· Breaker (Excavator Mounted)	¨ Fit suitably designed muffler or sound reduction equipment. ¨ Use dampened bit to eliminate ringing	Up to 15	5

· Dump Truck · Excavator · Bulldozer · Concrete Lorry Mixer	¨ Fit more efficient exhaust sound reduction equipment ¨ Manufacturers’ enclosure panels should be kept closed	5 to 10	5
· Chipper · Poker	¨ Fit suitably designed muffler or sound reduction equipment. ¨ Ensure all leaks in air line are sealed ¨ Use dampened bit to eliminate ringing	Up to 15	5

* Reference: Noise and vibration control on construction and open sites, BS5228: Part 1: 1997, P.15-16.

Table 5.12 Recommended Mitigation Measures for the Noisy Equipment during Permanent Noise Barrier Construction

Plant	Mitigation Measures*	Noise Reduction, dB(A)*	Reduction Assumed, dB(A)
· Excavator · Crane · Lorry · Concrete Lorry Mixer	¨ Fit more efficient exhaust sound reduction equipment ¨ Manufacturers’ enclosure panels should be kept closed	5 to 10	5
· Poker	¨ Fit suitably designed muffler or sound reduction equipment. ¨ Ensure all leaks in air line are sealed ¨ Use dampened bit to eliminate ringing.	Up to 15	5

Plant

Mitigation Measures*

Noise Reduction, dB(A)*

Reduction Assumed, dB(A)

· Excavator

· Crane

· Lorry

· Concrete Lorry Mixer

¨ Fit more efficient exhaust sound reduction equipment

¨ Manufacturers’ enclosure panels should be kept closed

5 to 10

· Poker

¨ Fit suitably designed muffler or sound reduction equipment.

¨ Ensure all leaks in air line are sealed

¨ Use dampened bit to eliminate ringing.

Up to 15

* Ref: Noise and vibration control on construction and open sites, BS5228: Part 1: 1997, P.15-16.

5.4.3.3 Temporary noise barriers are also required at SR4, SR13 and SR15 during road construction, and SR2 and SR4 during permanent noise barrier construction in Tung Chung, such that the stationary construction equipment will be totally screened providing a 10 dB(A) attenuation and a 5dB(A) attenuation provided for moving equipment. The equipment which can be screened to 10dB(A) and 5 dB(A) respectively is listed below:

Equipment receiving 10dB(A) reduction

- Air Compressor;

- Generator;

- Hand-Held Breaker;

- Mini Piling Rig;

- Poker;

- Saw; and

- Water Pump.

Equipment receiving 5dB(A) reduction

- Asphalt Paver;

- Chipper;

- Compactor;

- Concrete Lorry Mixer;

- Crane;

- Dump Truck;

- Dumper;

- Excavator;

- Excavator Mounted Breaker;

- Lorry (with Grab);

- Paint Line Marker;

- Power Rammer;

- Road Roller; and

- Roller Vibratory.

5.4.3.4 In addition to the above, the number of excavator mounted breakers in operation during road construction scenarios E1 (rock/earth excavation) and R1 (retaining wall foundation works) at any one time should be restricted from two to only one breaker in Tung Chung (SR 4) and the Cheung Sha area (SRs 13 and 15). Based upon the results shown in Tables 5.8a to 5.8e, no exceedance will occur when the receiver is located at 200m away from the all construction scenarios (Unmitigated noise level during the worst case scenario E1/R1 at SR7, which is 198m from the work, is 75db(A)). Therefore, the Contractor should ensure the distance between the construction work and the sensitive receiver is more than 200m when operating two breakers simultaneously.

5.4.3.5 Noise levels can be further controlled with the following standard noise pollution control clauses:

¨ good site practice to limit noise emissions at source;

¨ avoidance of simultaneous noisy activities;

¨ reduction in the numbers of plant operating in critical areas close to NSRs;

¨ use of a quiet equipment and maintenance of it so as to minimise noise; and

¨ proper planning of work area.

5.4.3.6 The maximum noise levels at the NSRs during the road construction phase and bridge construction with noise mitigation measures applied are shown in Table 5.13 and Table 5.14 respectively. A summary of the maximum mitigated levels at each representative NSR is provided in Figures 5.2a to 5.2e.

Table 5.13 Maximum Noise Levels (dB(A)) during Road Construction with Noise Mitigation

Sensitive Receiver	Slant Distance (m)	Noise Level with Mitigation, dB(A)
	(EW+PC/RW)⁽¹⁾	Earth Works			Retaining Wall				Pavement Construction
	Scenario	E1	E2	E3	R1	R2⁽²⁾	R3	R4	P1	P2	P3
	Mitigated SWL	120.9	115.3	117.9	120.9	116.9	115.8	114.0	114.3	115.9	115.0
SR1	235/325	*73	*67	*68	*71	*62	*63	*63	*66	*67	*63
SR2	114/238	75	*73	*75	*73	*64	*65	*65	*72	*73	*69
SR3	256/425	*73	*66	*68	*68	*59	*60	*60	*65	*66	*62
SR4#	56/162	74	70	73	64	*68	*69	*69	69	71	*75
SR5	162/211	72	*70	*72	*74	*65	*66	*66	*69	*70	*66
SR6	244/248	*73	*67	*68	*73	*64	*65	*65	*66	*66	*62
SR7	202/206	*75	*68	*70	*75	*66	*67	*66	*67	*68	*64
SR8	229/241	*74	*67	*68	*73	*64	*65	*65	*66	*67	*63
SR9	156/161	72	*71	*72	72	*68	*69	*69	*70	*70	*66
SR10	276/271	*72	*66	*67	*72	*63	*64	*64	*65	*65	*61
SR11	267/272	*72	*66	*67	*72	*63	*64	*64	*65	*65	*61
SR12	263/252	*72	*66	*67	*73	*64	*65	*65	*65	*66	*62
SR13#	32/32	78	75	78	78	74	74	74	74	76	70
SR14	151/145	72	*71	*72	73	*69	*70	*70	*70	*70	*66
SR15#	55/96	74	70	73	69	*72	*73	*73	70	71	*75
SR16	166/164	72	*70	*71	72	*68	*69	*68	*69	*70	*66
SR17	240/234	*73	*67	*68	*73	*65	*66	*65	*66	*66	*62
SR18	291/291	*72	*65	*66	*72	*63	*64	*63	*64	*65	*61

71	Scenarios requiring mitigation measures; mitigated noise level recorded.

Note: Relevant noise criteria for all sensitive receiver is 75dB(A).

(1): The first distance quoted relates to both earth works and pavement construction and the second distance in the column is from the NSR to the nearest retaining wall works.

* Noise level within the noise criteria before implementation of noise mitigation measure, the mitigation measure is not applied.

^#Temporary noise barrier is applied as mitigation measure.

Table 5.14 Maximum Noise Levels (dB(A)) during Bridge Construction with Noise Mitigation

Sensitive Receiver	Slant Distance (m)	Noise Level with Mitigation, dB(A)
	Slant Distance (m)	Deck Construction			Foundation Construction
	Scenario	D1	D2	D3	F1	F2	F3	F4
	Mitigated SWL	118.6	111.9	112.0	120.8	114.1	118.0	111.9
SR9	159	*71	*67	*63	72	*70	*69	*67
SR10	277	*66	*62	*58	*72	*65	*64	*62
SR11	323	*65	*60	*57	*71	*64	*63	*60
SR12	295	*65	*61	*58	*71	*65	*64	*61
SR13	231	*67	*63	*60	*74	*67	*66	*63
SR14	206	*68	*64	*61	*75	*68	*67	*64
SR15	218	*68	*64	*60	*74	*67	*66	*64
SR16	375	*63	*59	*56	*69	*63	*62	*59
SR17	460	*62	*57	*54	*68	*61	*60	*57
SR18	501	*61	*57	*53	*67	*60	*59	*57

71	Scenarios requiring mitigation measures; mitigated noise level recorded.

Note: Relevant noise criteria for all sensitive receiver is 75dB(A).

* Noise level within the noise criteria before implementation of noise mitigation measure, the mitigation measure is not applied.

5.4.3.7 Table 5.13 and Table 5.14 shows that the recommended mitigation measures are sufficient to reduce levels to within the noise standard during road and bridge construction works, with the exception of SR13 during road works.

5.4.3.8 Further mitigation measures are required for SR13 during the construction scenario E1, E3, R1 and P2 at South Lantau Road. Restriction on the period of operation of power mechanical equipment is, therefore, required. When the operation time of the breaker, dump truck, bulldozer and grader is restricted by 50%, the predicted noise level would be 75dB(A) during scenarios E1, E3, R1 and P2 and no exceedance would occur.

5.4.3.9 The maximum noise levels at the NSRs during the permanent noise barrier construction with noise mitigation measures applied are shown in Table 5.15. A summary of the maximum mitigated levels at each representative NSR is provided in Figures 5.2a to 5.2e.

Table 5.15 Maximum Noise Levels (dB(A)) during Construction of Permanent Noise Barrier in Tung Chung Valley With Noise Mitigation

Sensitive Receiver	Slant Distance (m)	Noise Level with Mitigation, dB(A)
	Slant Distance (m)	Construction of Noise Barrier
	Scenario	NB1A	NB1B	NB1C	NB2	NB3	NB4A	NB4B	NB5A	NB5B
	Mitigated SWL^#	104.3	102.5	102.0	103.4	102.1	105	102.0	102.0	102.0
SR1A	200	*63	*61	*61	*62	*64	*54	*61	*61	*61
SR1B	179	*64	*62	*62	*63	*65	*55	*62	*62	*62
SR1	153	*66	*64	*63	*65	*66	*56	*63	*63	*63
SR1C	149	*66	*64	*64	*65	*66	*57	*64	*64	*64
SR2A	96	*70	*68	*67	*69	*70	*60	*67	*67	*67
SR2B	60	*74	*72	*71	*73	*74	*64	*71	*71	*71
SR2	40	67	*75	*75	66	65	*68	*75	*75	*75
SR2C	21	73	71	71	72	71	*74	71	71	71
SR2D	25	71	70	69	70	69	*72	69	69	69
SR3	242	*62	*60	*59	*61	*62	*52	*59	*59	*59
SR4A	50	*75	*74	*73	*74	63	*66	*73	*73	*73
SR4	48	66	*74	*73	*75	63	*66	*73	*73	*73
SR4B	39	67	66	*75	67	65	*68	*75	*75	*75
SR4C	46	66	*74	*74	*75	64	*67	*74	*74	*74
SR4D	25	71	70	69	70	69	*72	69	69	69
SR5	168	*65	*63	*62	*64	*65	*55	*62	*62	*62

71	Scenarios requiring mitigation measures; mitigated noise level recorded
*	Noise level within the noise criteria before implementation of noise mitigation measure, the mitigation measure is not applied
^#	Temporary noise barrier is taken into account on the total sound power level for SR2 and SR4

5.4.3.10 After the implementation of above noise mitigation measures, the noise during construction of the permanent noise barrier will be reduced to acceptable levels.

Cumulative Effect

5.4.3.11 In order to prevent the cumulative effect due to the simultaneous construction activities, the operation of gangs of equipment should keep a certain distance between each other. According to the Table 4 – Summation of Noise Levels, Technical Memodrandum on Noise From Construction Work Other Than Percussive Piling, the amount in dB(A) add to the higher noise level would be 0 dB(A), if the difference between two noise levels are more than 12 dB(A). In the worst case construction scenario E1 and R1 and based upon the closest NSR, a distance of 150m between two gangs is sufficient to eliminate the cumulative effect.

Nighttime Working

5.4.3.12 In addition to works being on-going during the unrestricted period of 7.00am to 7.00pm weekdays and Saturdays, it is likely that construction works will also be undertaken during Restricted Period 1, between 7.00pm and 11.00pm in the evening and on public holidays in order to condense the works programme as far as possible. Works during restricted periods are controlled by the Noise Control Ordinance and the Contractor will be required to obtain a Construction Noise Permit (CNP) before undertaking any construction activities involving powered mechanical equipment in these times.

5.4.3.13 Notwithstanding, based upon the worst case construction activity and based upon the Restricted Period 1 noise criteria for residential properties of 60 dB(A), the maximum setback from residential properties for evening and public holiday working has been determined. The setback has been calculated using Table 5 – Correction Factors to Obtain the Predicted Noise Level from Sound Power Level at Given Distances, Technical Memodrandum on Noise From Construction Work Other Than Percussive Piling and for the distance greater than 300m, the correction factors is calculated based on the standard acoustical principles and practices and the proposed silenced equipment will be used during all construction scenario assumed. Based upon this, Figure 5.7 shows the areas where works during the evening and public holidays are likely to be able to take place, subject to the Contractor obtaining a valid CNP. Further details on the requirement for a CNP are provided in Section 3.3.2.

Summary of Dwellings Affected

5.4.3.11 The approximate number of dwellings affected by the works, based upon the maximum noise levels during the construction activities, and the number of dwellings benefiting from the mitigation measures are summarised in Table 5.16 below, where one building has assumed to be one dwelling. The result show that, in the worst case, about 44 dwellings will be affected by the construction works, and all can be protected by the mitigation measures detailed in the section above.

Table 5.16 Summary of Dwellings Affected by Adverse Construction Noise and Benefitting from Mitigation Measures

Sensitive Receiver	Number of Dwelling Experiencing Noise Exceed Criteria without Mitigation Applied			Number of Dwelling Experiencing Noise Exceed Criteria with Mitigation Applied			Number of Dwelling Benefiting from the Mitigation Measures
Sensitive Receiver	Affected Dwelling of NSR itself	Affected Dwellings in Vicinity	Sub-total	Affected Dwelling of NSR itself	Affected Dwellings in Vicinity	Sub-total	Affected Dwelling of NSR itself	Affected Dwellings in Vicinity	Sub-total
SR1	1	14	15	0	0	0	1	14	15
SR2	1	14	15	0	0	0	1	14	15
SR3	0	0	0	0	0	0	0	0	0
SR4	1	10	11	0	0	0	1	10	11
SR5	0	0	0	0	0	0	0	0	0
SR6	0	0	0	0	0	0	0	0	0
SR7	0	0	0	0	0	0	0	0	0
SR8	0	0	0	0	0	0	0	0	0
SR9	1	0	1	0	0	0	1	0	1
SR10	0	0	0	0	0	0	0	0	0
SR11	0	0	0	0	0	0	0	0	0
SR12	0	0	0	0	0	0	0	0	0
SR13	1	0	1	0	0	0	1	0	1
SR14	0	0	0	0	0	0	0	0	0
SR15	1	0	1	0	0	0	1	0	1
SR16	0	0	0	0	0	0	0	0	0
SR17	0	0	0	0	0	0	0	0	0
SR18	0	0	0	0	0	0	0	0	0
SR19	0	0	0	0	0	0	0	0	0
Total			44			0			44

5.4.4 Residual Construction Impacts

5.4.4.1 Based upon the application of the recommended mitigation measures, the noise level at all sensitive receivers will be within the relevant noise criteria, and no adverse residual impacts are predicted.

5.5 Operational Noise Impact Assessment

5.5.1 Model Application

Road Traffic

5.5.1.1 Operational noise is largely attributable to road traffic. The impact of road noise arising from the Improved Tung Chung Road, South Lantau Road and internal roads in the Tung Chung development, as shown in Section 2, have been calculated at the facades of the representative NSRs in terms of L_10(1hour) in dB(A) using the SoundPlan package. The calculation methodology was based on the Calculation of Road Traffic Noise (CRTN) methodology, issued by the UK Department of Transport in 1988.

5.5.1.2 The following assumptions have been made for the purposes of the noise modelling:

¨ peak hour traffic flows and vehicle mixes for the worst case year of 2021 based on data provided by the traffic and transportation modelling study. All the traffic data have been approved for use by the Transport Department, see Appendix G;

¨ in view of the close proximity of the NSRs to the noise sources, effects due to the absorption by air have not be allowed for;

¨ meteorological conditions have not been allowed for due to the proximity of the receivers to the noise source; and

¨ the limit for the proposed road has stipulated speed been assumed to be 50 km per hour for the Improved Tung Chung Road, South Lantau Road, Shek Mun Kap Road, Yu Tung Road and Road L7.

¨ no idling and waiting will be undertaken in the bus lay-bys or the turning circle for extended periods. Noise generated in these areas are included in the noise modelling.

5.5.2 Noise Criteria

5.5.2.1 The impact of operational noise has been assessed with reference to the TMEIA and the maximum L_10(1hour) traffic noise levels at sensitive facades are shown in Table 3.4

5.5.3 Modelling Results

5.5.3.1 The predicted traffic flow figures for the noise modelling for the prevailing year of 2006 and the worst case design year 15 years after the opening of the road of 2021 are detailed in Section 2.8. Transport Department’s approval of the traffic figures for use in the EIA, together with a figure showing the road links which have been input into the noise model, are provided in Appendix G.

5.5.3.2 The L_10(1hour) noise levels in dB(A) at the representative NSRs during the operational phase without noise mitigation measures applied are shown in Table 5.17 below. The predicted noise levels at identified future sensitive receiver associated with the sales sites in the vicinity of the junction of the new Tung Chung Road with the South Lantau Road are shown in Table 5.18. Values at every floor of each sensitive receiver are given below and a complete set of modelling results are provided in Appendix G. A summary of the maximum unmitigated operational noise levels at each NSR is also provided in schematic form in Figures 5.4a to 5.4f. Additional modelling points have been designated at SR13 as shown in Figure 5.3b.

Table 5.17 Predicted Traffic Noise Levels, L_10
(1hour), dB(A), at the Noise Sensitive Receivers During Operation Phase Without Noise Mitigation Measures in the Year 2021

Sensitive Receiver	Floor	Predicted Prevailing L₁₀ Noise (1hour), dB(A)	Predicted L₁₀ Noise Level (1 hour) dB(A) (without noise mitigation) (Criteria 70 dB(A)
SR1	1	70.2	76.4
	2	70.2	76.5
	3	70.0	76.4
SR2	1	71.4	76.5
	2	71.2	76.6
	3	70.8	76.4
SR3	1	67.2	67.7
	2	67.1	67.8
	3	67.1	67.8
SR4	1	62.7	70.3
	2	62.7	70.5
	3	62.7	70.5
SR5	1	58.6	59.2
	2	58.6	60.1
	3	58.7	60.9
SR6	1	64.4	62.6
	2	64.2	64.6
	3	64.1	64.7
SR7	1	66.7	63.3
	2	66.3	68.3
	3	65.9	68.2
SR8	1	65.4	64.8
	2	65.3	64.7
	3	65.4	64.6
SR9	1	60.1	60.9
SR10	1	50.4	51.8
SR10	2	50.4	51.9
SR11	1	55.0	58.5
	2	55.1	58.9
	3	55.1	59.2
SR12	1	52.5	57.9
	2	52.9	58.2
	3	53.2	58.7
SR13a	1	66.9	68.5
SR13b	1	68.0	69.5
SR13c	2	59.7	60.9
SR14	1	46.1	49.5
SR14	2	46.4	49.8
SR15	1	62.5	64.2
SR16	1	53.8	55.5
	2	59.2	60.7
	3	67.9	69.4
SR17	1	64.5	66.1
	2	64.5	66.1
	3	64.4	66.1
SR18	1	67.1	68.5
	2	67.0	68.4
	3	66.9	68.3

70.6	Noise Level at Sensitive Receiver exceed the relevant Noise Criteria

Table 5.18 Predicted Traffic Noise Levels, L_10
(1hour), dB(A), at the Future Noise Sensitive Receivers of the Cheung Sha Sale Sites During Operation Phase Without Noise Mitigation Measures in the Year 2021

Sensitive Receiver	Floor	Predicted L₁₀ Noise Level (1 hour) dB(A) (without noise mitigation) (Criteria 70 dB(A))
CS1	1	67.2
CS1	2	69.0
CS2	1	65.3
CS2	2	66.8
CS3	1	60.0
CS3	2	61.5
CS4	1	60.9
CS4	2	61.9
CS5	1	64.1
CS5	2	65.9

CS6	1	69.0
CS6	2	71.1
CS7	1	70.4
CS7	2	71.6
CS8	1	65.3
CS8	2	67.4
CS9	1	70.2
CS9	2	71.4
CS10	1	71.3
CS10	2	72.1
CS11	1	66.6
CS11	2	67.3
CS12	1	70.9
CS12	2	70.9
CS13	1	68.1
CS13	2	68.1

5.5.3.3 The results for the improved Tung Chung Road indicate that operational noise will affect some sensitive receivers. The noise level at sensitive receivers SR3, SR5 to SR18 are protected either by their distance or the fact that the alignment is elevated as it passes. However, the modelling has predicted that sensitive receivers SR1, SR2 and SR4 in Tung Chung will be subject to operational noise levels in excess of the 70dB(A) limit for residential properties. However, the results in Appendix G indicate that the main noise contribution affecting SR1 and SR2 is from the section of Tung Chung Road which is outside this project limit and partly Yu Tung Road, with the improved Tung Chung Road included in this project having a negligible contribution.

5.5.3.4 However, in order to obtain further detailed information on the noise impacts in the Tung Chung area as a basis for determining the optimum configuration for mitigation measures, addition sensitive receivers have been identified. The addition sensitive receivers are list in Table 5.19 below and shown in Figure 5.3a. The L_10(1hour) noise levels in dB(A) at the additional representative NSRs during the operational phase without noise mitigation measures applied are shown in Table 5.20 below for reference.

Table 5.19 Additional Noise Sensitive Receivers at Tung Chung

NSR Ref.	NSR	No. of Floor	Shortest Distance (m)	Description
SR1A	10, Ha Ling Pei	3	273	Residential
SR1B	8, Ha Ling Pei	3	256	Residential
SR1C	7, Ha Ling Pei	3	215	Residential
SR2A	14, Wong Ka Wai	3	165	Residential
SR2B	9, Wong Ka Wai	3	132	Residential
SR2C	7, Wong Ka Wai	3	99	Residential
SR2D	3A, Wong Ka Wai	3	83	Residential
SR4A	10A, Lung Tseng Tau	3	60	Residential
SR4B	7, Lung Tseng Tau	3	45	Residential
SR4C	13, Lung Tseng Tau	3	55	Residential
SR4D	28, Lung Tseng Tau	3	34	Residential
SR4C	13, Lung Tseng Tau	3	55	Residential
SR4D	28, Lung Tseng Tau	3	34	Residential

Table 5.20 Predicted Traffic Noise Levels, L_10
(1hour), dB(A), at the Additional Noise Sensitive Receivers in Tung Chung During Operation Phase Without Noise Mitigation Measures in the Year 2021

Sensitive Receiver	Description	Floor	Noise Criteria, dB(A)	Predicted Prevailing L₁₀ Noise (1hour), dB(A)	Predicted L₁₀ Noise Level (1 hour) dB(A) (Without Noise Mitigation)
SR1A	Residential	1	70	69.3	74.3
		2	70	69.3	74.5
		3	70	69.3	74.5
SR1B	Residential	1	70	69.6	75.0
		2	70	69.6	75.2
		3	70	69.6	75.2
SR1	Residential	1	70	70.2	76.4
		2	70	70.2	76.5
		3	70	70.0	76.4
SR1C	Residential	1	70	68.9	75.2
		2	70	68.9	75.3
		3	70	68.8	75.2
SR2A	Residential	1	70	67.4	73.3
		2	70	67.4	73.6
		3	70	67.4	73.6
SR2B	Residential	1	70	67.3	73.3
		2	70	67.3	73.5
		3	70	67.3	73.6
SR2	Residential	1	70	71.4	76.5
		2	70	71.2	76.6
		3	70	70.8	76.4
SR2C	Residential	1	70	70.7	75.1
		2	70	70.5	75.1
		3	70	70.1	75.1
SR2D	Residential	1	70	64.1	67.7
		2	70	64.1	67.8
		3	70	64.1	67.8
SR4A	Residential	1	70	66.7	70.2
		2	70	66.7	70.4
		3	70	66.7	70.4
SR4	Residential	1	70	62.7	70.4
		2	70	62.7	70.5
		3	70	62.7	70.5

SR4B	Residential	1	70	67.2	70.8
		2	70	67.2	70.9
		3	70	67.1	70.9
SR4C	Residential	1	70	61.6	64.1
		2	70	61.7	64.3
		3	70	61.7	64.5
SR4D	Residential	1	70	67.4	70.1
		2	70	67.4	70.2
		3	70	67.3	70.3

70.6	Noise Level at Sensitive Receiver exceeds the relevant Noise Criteria

5.5.4 Operational Mitigation Measures

5.5.4.1 Based upon the above Table 5.20 it can be seen that the majority of the residential properties in the Tung Chung area will be subject to noise levels in excess of the criteria and will require mitigation measures. Table 5.18 also shows that the future properties closest to the proposed road at the future sale sites in Cheung Sha will also need protection.

Tung Chung

5.5.4.2 In respect of Tung Chung, as the road is being widened on-line along this section is it not possible to move the alignment further away from the sensitive receivers as a means to reduce the noise impacts. In addition, due the low speed limit of the road and the presence of the numerous ingress and egress points and the roundabout, noise reducing surfacing would not be effective.

5.5.4.3 Thus, a full range of noise structures have been considered for the protection of the NSRs to ensure that the optimum scheme is recommended. The noise predictions (see Appendix G) confirm that the noise levels in excess of the 70 dB(A) criteria at SRs 1, 1A, 1B, 1C, 2, 2A, 2B and 2C in Wong Ka Wai and Ha Ling Pei are as a result of traffic on the “existing” roads (other sections of Tung Chung Road and Yu Tung Road) which are not being modified as part of this project. However, in accordance with the ExCo policy endorsed in November 2000, retrofitting of direct mitigation measures on the existing Tung Chung Road to protect these properties has been assessed. The guiding principles to be taken into account when considering retrofitting of barrier to existing roads include:

¨ the new structures should not obstruct emergency access or fire fighting;

¨ the structures should not undermine road safety or impede pedestrian and vehicular movement;

¨ the structures should not interfere with commercial activities or cause social disruptions; and

¨ adequate space for retrofitting is available.

5.5.4.4 There are numerous pedestrian and vehicular access points to the private properties and land adjacent to the road between Ha Ling Pei and Wong Ka Wai, as shown on Figure 5.5, and these run-ins need to be maintained. The access points are indicated on the gazette plans and it has been determined at gaps of 4m should be provided in each case. As such, any retrofitted barrier along this stretch of road would need to have may gaps in it to allow access to be maintained. Based upon standard acoustic principals and practices, the presence of numerous gaps and openings would degrade the performance of any noise barriers, with the barriers having to be of an incommensurate height for the rural setting to compensate for the noise getting through the gaps.

5.5.4.5 Futhermore, sight-line requirements have to be taken into account and this would require any barrier to be located tight against the boundary of the private land and thus, an overlapping barrier at the front of this to screen the gaps would compromise the sightline. In addition, due to space constraints between the widened road and the private property in Tung Chung Village, there would be insufficient space to provide an overlapping noise barrier at the back of the structure without affecting private land, as shown in Figure 5.5. It would also not be possible to reduce the number of gaps by providing common access without affecting private land. Therefore, retrofitted direct mitigation measures along most of the section of road in Ha Ling Pei and Wong Ka Wai are not considered practical.

5.5.4.6 However, there is a length of road of 70m which does not have any gaps, and it has been determined that a barrier of between 3 to 5m in height could be installed and would provide some reduction of the noise levels at some NSRs in this area. The barrier would also comply with the guidelines for retrofitting. The location of the possible future section of retrofitted barrier identified is shown in Figure 5.5.

5.5.4.7 In summary, retrofitting of barriers is not considered practical for much of the section of road in front of Ha Ling Pei and Wong Ka Wai. Therefore, the test according to the three Eligibility Criteria for Indirect Technical Remedies defined under the ExCo directive “Equitable Redress for Persons Exposed to Increased Noise Resulting from the Use of New Roads” has been applied to these NSRs. The three criteria are:

(i) the predicted overall noise level from the new road together with other traffic noise in the vicinity must be above 70 dB(A) for domestic premises and 65 dB(A) for school;

(ii) the predicted overall noise level is at least 1.0 dB(A) more than the prevailing traffic noise level; i.e. the total traffic noise level existing before the works to construct the road were commenced; and

(iii) the contribution to the increase in the predicted overall noise level from the new road must be at least 1.0 dB(A).

5.5.4.8 The three eligibility criteria test for the maximum noise levels at the NSR are shown in Appendix G. However, it can be seen in Appendix G that due to the contribution of noise from existing roads, these properties are not eligible for indirect technical remedies. Nevertheless, upon commissioning of the project, it is recommended that a review of the situation be initiated by HyD based upon the contemporary conditions to see whether any noise mitigation measures that could bring significant benefit to this section of Tung Chung Road, between the Project limit and the study boundary (see Figure 5.5), covering Wong Ka Wai and Ha Ling Pei, could be achieved.

5.5.4.9 For the properties which are affected by noise to above the acceptable limit from the widened section of Tung Chung Road which forms part of this project (SRs 4 and 4B), direct noise mitigation measures for implementation under this project have been considered. As noted above, due to the speed limit of the road, the numbers of heavy vehicles and the numerous access points, noise reducing road surfacing is not practical and the road alignment cannot be moved further away from the sensitive receivers. Therefore, various heights of noise barrier and canopy have been considered. It has been determined that the transmission loss^[1] for the barriers should be at least 30 dB in order to screen the noise from the road to the sensitive receiver. Most of the commercially available noise mitigation panels in Hong Kong can achieve this criteria. The full set of modelling results can be seen in Appendix G and the results are discussed below.

5.5.4.10 Three sections of noise barrier have been proposed at the front of the properties at Lung Tseng Tau, two of 1.5m in height and one of 4.5m. Barriers will be located behind the proposed footpath and paved amenity area near to the roundabout to take account of the sight-line requirements on the inside of the road bends and at the roundabout, as shown in Figure 5.5. One gap of 4m has been provided between two of the sections of barrier to accommodate an existing pedestrian access to the private properties behind the road in Lung Tseng Tau, as shown in Figure 5.5. While a height of 1.5m for the middle section of barrier is sufficient to reduce the noise to within acceptable levels, it is considered that it would be preferable from an aesthetic perspective the vary the height of this barrier from 1.5m to 4.5m to blend with the other barriers either side. The proposed barriers also have the benefit of providing noise attenuation for other residential properties in the area which are not adversely affected by traffic noise.

5.5.4.11 The extent of the mitigation determined in Tung Chung is summarised in Table 5.21 below and detailed in Figure 5.5. A total length of 127m of noise barriers has been recommended in the Tung Chung area and an indicative cross-section of the barrier is provided in Figure 5.6. The maximum mitigated noise levels at each of the NSRs is given in Table 5.22 and a summary of the maximum unmitigated and mitigated levels at each NSR provided in Figures 5.4a to 5.4e. While existing and future residential properties will be opposite the road, the distance of these (greater than 300m) means that reflective barriers can be used. This also has aesthetic advantages and a photomontage of the proposed barriers is also provided in Section 9.

Table 5.21 Summary of Direct Mitigation Measures

Barrier Height	Location of Barrier	Length of Barrier	Barrier Type
4.5m	Lung Tseng Tau	30m	Reflective
1.5m to 4.5m barrier (graded height)	Lung Tseng Tau	59m	Reflective
1.5m barrier	Lung Tseng Tau	38m	Reflective

Table 5.22 Noise Levels, L_{10 (1hour)}, dB(A), at the Additional Noise Sensitive Receivers at Tung Chung During Operation Phase With Noise Mitigation Measures in the Year 2021

Sensitive Receiver	Floor	Noise Criteria, dB(A)	Predicted L₁₀ Noise Level (1 hour) dB(A) (Without Mitigation)	Predicted L₁₀ Noise Level (1 hour) dB(A) (With Noise Mitigation)
SR1A	1	70	74.3	71.8
	2	70	74.5	73.1
	3	70	74.5	73.7
SR1B	1	70	75.0	71.6
	2	70	75.2	73.4
	3	70	75.2	74.3
SR1	1	70	76.4	72.7
	2	70	76.5	75.0
	3	70	76.4	75.8
SR1C	1	70	75.2	71.3
	2	70	75.3	73.1
	3	70	75.2	74.2
SR2A	1	70	73.3	70.1
	2	70	73.6	71.7
	3	70	73.6	72.4
SR2B	1	70	73.3	69.8
	2	70	73.5	71.7
	3	70	73.6	72.6
SR2	1	70	76.5	72.9
	2	70	76.6	75.8
	3	70	76.4	76.2
SR2C	1	70	75.1	72.3
	2	70	75.1	74.7
	3	70	75.1	74.9
SR2D	1	70	67.7	62.3
	2	70	67.8	64.5
	3	70	67.8	65.4

SR3	1	70	67.7	67.7*
	2	70	67.8	67.8*
	3	70	67.8	67.8*
SR4A	1	70	70.2	65.2
	2	70	70.4	66.6
	3	70	70.4	67.7
SR4	1	70	70.4	65.2
	2	70	70.5	66.6
	3	70	70.5	67.8
SR4B	1	70	70.8	65.9
	2	70	70.9	67.4
	3	70	70.9	68.6
SR4C	1	70	64.1	61.7
	2	70	64.3	62.4
	3	70	64.5	62.9
SR4D	1	70	70.1	68.9
	2	70	70.2	69.3
	3	70	70.3	69.6
SR5	1	70	59.2	59.1*
	2	70	60.1	59.7*
	3	70	60.9	60.5*
SR6	1	70	62.6	62.6*
	2	70	64.6	64.6*
	3	70	64.7	64.7*
SR7	1	70	63.3	63.3*
	2	70	68.3	68.3*
	3	70	68.2	68.2*
SR8	1	70	64.8	64.8*
	2	70	64.7	64.7*
	3	70	64.6	64.6*
SR9	1	70	60.9	60.9*
SR10	1	70	51.8	51.7*
SR10	2	70	51.9	51.9*
SR11	1	70	58.5	58.5*
	2	70	58.9	58.8*
	3	70	59.2	59.1*
SR12	1	70	57.9	57.8*
	2	70	58.2	58.1*
	3	70	58.7	58.6*
SR13a	1	70	68.5	68.5*
SR13b	1	70	69.5	69.5*
SR13c	2	70	60.9	60.9*
SR14	1	70	49.5	49.3*
SR14	2	70	49.8	49.7*
SR15	1	70	64.2	64.1*

SR16	1	70	55.5	55.4*
	2	70	60.7	60.7*
	3	70	69.4	69.4*
SR17	1	70	66.1	66.1*
	2	70	66.1	66.1*
	3	70	66.1	66.0*
SR18	1	70	68.5	68.5*
	2	70	68.4	68.4*
	3	70	68.3	68.3*

* Noise level within the noise criteria before implementation of noise mitigation measures, thus, mitigation measure is not required.

Cheung Sha

5.5.4.12 Some of the planned receivers at the sale sites in Cheung Sha will also be subject to noise levels which exceed the noise criteria L₁₀ 70dB(A) based upon the assumed 10m setback from the site boundary and the assumption that the properties will be facing towards the sea. Thus, mitigation measures to protect the future properties is required.

5.5.4.13 Barriers cannot be provided along the edge of the proposed road due to vehicle sightline issues associated with the bus lay-bys, the curve of the road as it descends to South Lantau Road and the roundabout junction with South Lantau Road. Due to the junction and its approach, noise reducing road surfacing would also not be effective in this area.

5.5.4.14 Table 5.23 shows that a 2 meter high landscaped bund, together with a 4m non-building area along the boundary of the sites facing the new Tung Chung Road, as indicated in Figure 5.4f, would be sufficient to reduce noise levels to within the acceptable criteria. The proposed mitigation has been confirmed as acceptable with Planning Department and the District Lands Office. The maximum mitigated noise levels at each of the NSRs is given in Table 5.23 and a summary of the maximum unmitigated and mitigated levels at each NSR provided in Figures 5.4f.

Table 5.23 Predicted Traffic Noise Levels, L_10
(1hour), dB(A), at the Noise Sensitive Receivers in Sale Sites During Operation Phase With Mitigation in the Year 2021

Sensitive Receiver	Floor	Predicted L₁₀ Noise Level (1 hour) dB(A) (without noise mitigation) (Criteria 70 dB(A))	Predicted L₁₀ Noise Level (1 hour) dB(A) (with noise mitigation) (Criteria 70 dB(A))
CS1	1	67.2	66.7
CS1	2	69.0	68.3
CS2	1	65.3	64.0
CS2	2	66.8	65.5
CS3	1	60.0	59.4
CS3	2	61.5	60.8

CS4	1	60.9	60.4
CS4	2	61.9	61.3
CS5	1	64.1	61.2
CS5	2	65.9	63.3
CS6	1	69.0	62.8
CS6	2	71.1	64.9
CS7	1	70.4	67.8
CS7	2	71.6	68.5
CS8	1	65.3	63.7
CS8	2	67.4	66.0
CS9	1	70.2	66.0
CS9	2	71.4	68.6
CS10	1	71.3	63.0
CS10	2	72.1	66.5
CS11	1	66.6	63.2
CS11	2	67.3	65.2
CS12	1	70.9	67.6
CS12	2	70.9	68.5
CS13	1	68.1	66.8
CS13	2	68.1	67.3

Summary of Dwellings Affected and Benefitting

5.5.4.15 A summary of the dwellings benefitting from the mitigation before and after the implementation of direct noise measures is provided in Table 5.24 below. The results shows that, in the worst case, of the 10 dwellings which are predicted to be affected by the operation of improved Tung Chung Road which forms this project, all will be benefit from the mitigation structures proposed. Those dwellings which are not adversely affected by this project but by other existing roads are highlighted but as the source of the noise is outside the scope of this project, no mitigation measures are proposed.

Table 5.24 Summary of Dwelling Affected by Adverse Noise and Benefitting from Direct Mitigation Measures during the Operational Phase

Sensitive Receiver	*Number of Dwelling Experiencing Noise Exceed Criteria without Mitigation**			*Number of Dwelling Experiencing Noise Exceed Criteria with Mitigation**			*Number of Dwelling Benefiting from the Mitigation Measures**
Sensitive Receiver	Affected by New Road	Affected by Existing Roads⁽¹⁾	Sub-total	Affected by New Road	Affected by Existing Roads⁽¹⁾	Sub-total	Affected by New Road	Affected by Existing Roads⁽¹⁾	Sub-total
SR1	0	15	15	0	15	15	0	0	0
SR2	0	16	16	0	16	16	0	0	0
SR3	0	0	0	0	0	0	0	0	0
SR4	5	0	5	0	0	0	5	0	5
SR5	0	0	0	0	0	0	0	0	0
SR6	0	0	0	0	0	0	0	0	0
SR7	0	0	0	0	0	0	0	0	0
SR8	0	0	0	0	0	0	0	0	0
SR9	0	0	0	0	0	0	0	0	0
SR10	0	0	0	0	0	0	0	0	0
SR11	0	0	0	0	0	0	0	0	0
SR12	0	0	0	0	0	0	0	0	0
SR13	0	0	0	0	0	0	0	0	0
SR14	0	0	0	0	0	0	0	0	0
SR15	0	0	0	0	0	0	0	0	0
SR16	0	0	0	0	0	0	0	0	0
SR17	0	0	0	0	0	0	0	0	0
SR18	0	0	0	0	0	0	0	0	0
CS1	0	0	0	0	0	0	0	0	0
CS2	0	0	0	0	0	0	0	0	0
CS3	0	0	0	0	0	0	0	0	0
CS4	0	0	0	0	0	0	0	0	0
CS5	0	0	0	0	0	0	0	0	0
CS6	1	0	1	0	0	0	1	0	1
CS7	1	0	1	0	0	0	1	0	1
CS8	0	0	0	0	0	0	0	0	0
CS9	1	0	1	0	0	0	1	0	1
CS10	1	0	1	0	0	0	1	0	1
CS11	0	0	0	0	0	0	0	0	0
CS12	1	0	1	0	0	0	1	0	1
CS13	0	0	0	0	0	0	0	0	0
Total	10	31	41	0	31	31	10	0	10

* Number of dwellings shown comprises affected dwelling of the NSR itself together with the affected dwellings in the vicinity which the NSR represents.

(1) Dwellings affected by traffic noise on existing roads not within the scope of the project and thus mitigation not provided by this project.

5.5.5 Residual Operational Impacts

5.5.5.1 Table 5.24 shows that the application of the direct noise mitigation measures will protect all properties which are subject to noise from the project. All other properties within the study boundary are affected by noise from other roads and the while not eligible for indirect technical remedies the possibility of retrofitting a section of barrier to reduce the noise levels at some NSRs has been raised as detailed above.

5.6 Residual Impacts

5.6.1 The assessment of construction noise has determined that approximately 45 dwellings will be affected by the implementation of the project in excess of the stipulated standards. However, mitigation measures during construction phases have been recommended which can achieve adequate attenuation of noise in all construction scenarios and no adverse residual impact is predicted.

5.6.2 During operational phase of improved Tung Chung Road, no residential dwellings which are affected by this project will experience noise above 70dB(A) standard after implementation of direct noise mitigation measures.

5.7 Environmental Monitoring and Audit

5.7.1 The assessment has concluded that construction and operational noise impacts can be mitigated to acceptable levels. However, it is recommended that construction phase environmental monitoring and audit is undertaken to ensure that the recommended mitigation measures are being implemented and are effective. EM&A for operational noise is also recommended to ensure noise barriers are effective. Operational noise monitoring is recommended to be conducted twice during the 6th and 12th months during the first operational year of the road. Further details of the specific EM&A requirements are detailed in Section 13.0 of this report and in the EM&A Manual.

^[1]According to the Guidelines on Design of Noise Barrier by Environmental Protection Department and Highway Department, Government of the Hong Kong SAR, transmission loss (TL) is the common logarithm of energy ratios of the noise in front of the barrier and behind the barrier, expressed in decibels (dB). The TL of material used for a barrier should at least 10dB(A) greater than the desired noise reduction.

Table 5.9 Lmax dB(A) of Common Helicopter Types in Hong Kong

Table 5.9 L_max dB(A) of Common Helicopter Types in Hong Kong