CONTENTS

3 AIR QUALITY. 3-1

3.1 Introduction. 3-1

3.2 Relevant Legislation and Guidelines. 3-2

3.3 Existing Environment 3-4

3.4 Identification of Air Sensitive Receivers. 3-9

3.5 Construction Dust Impact Assessment 3-13

3.6 Operational Air Quality Impact Assessment 3-31

3.7 Environmental Monitoring and Audit 3-40

3.8 Conclusions. 3-40

TABLES

Table 3.1 Hong Kong Air Quality Objectives 3-2

Table 3.2 EPD Air Quality Monitoring Data at Tung Chung AQMS (2017 – 2021) 3-4

Table 3.3 AAHK Air Quality Monitoring Data at Sha Chau Station (2017 – 2021) 3-5

Table 3.4 AAHK Air Quality Monitoring Data at North Station (2017 – 2021) 3-6

Table 3.5 AAHK Air Quality Monitoring Data at South Station (2017 – 2021) 3-7

Table 3.6 Future Background Air Quality from PATH v2.1 for Year 2025 3-8

Table 3.7 Representative Air Sensitive Receivers 3-10

Table 3.8 Key Dust Emission Factors Adopted in the Assessment 3-21

Table 3.9 Predicted Cumulative Concentrations of TSP, RSP and FSP at the Most Affected Assessment Levels of ASRs 3-28

Table 3.10 Predicted Cumulative Concentrations of RSP and FSP at the Most Affected Assessment Levels of ASRs 3-38

Table 3.11 Predicted Cumulative Concentrations of NO₂ and SO₂ at the Most Affected Assessment Levels of ASRs 3-39

FIGURES

Figure 3.1 Locations of Air Quality Monitoring Stations and the Concerned PATH Grids

Figure 3.2 Locations of Representative Air Sensitive Receivers (Construction Phase)

Figure 3.3 Locations of Representative Air Sensitive Receivers (Operational Phase)

Figure 3.4 Contour of Cumulative Maximum 1-hour TSP Concentration (µg/m³) at 1.5mAG (Construction Phase)

Figure 3.5 Contour of Cumulative 10^th Highest Daily RSP Concentration (µg/m³) at 1.5mAG (Construction Phase)

Figure 3.6 Contour of Cumulative Annual RSP Concentration (µg/m³) at 1.5mAG (Construction Phase)

Figure 3.7 Contour of Cumulative 36^th Highest Daily FSP Concentration (µg/m³) at 1.5mAG (Construction Phase)

Figure 3.8 Contour of Cumulative Annual FSP Concentration (µg/m³) at 1.5mAG (Construction Phase)

Figure 3.9 Contour of Cumulative 10^th Highest Daily RSP Concentration (µg/m³) at 15.0mAG (Operational Phase)

Figure 3.10 Contour of Cumulative Annual RSP Concentration (µg/m³) at 1.5mAG (Operational Phase)

Figure 3.11 Contour of Cumulative 36^th Highest Daily FSP Concentration (µg/m³) at 1.5mAG (Operational Phase)

Figure 3.12 Contour of Cumulative Annual FSP Concentration (µg/m³) at 1.5mAG (Operational Phase)

Figure 3.13 Contour of Cumulative 19^th Highest Hourly NO₂ Concentration (µg/m³) at 1.5mAG (Operational Phase)

Figure 3.14 Contour of Cumulative Annual NO₂ Concentration (µg/m³) at 1.5mAG (Operational Phase)

Figure 3.15 Contour of Cumulative Maximum 10-min SO₂ Concentration (µg/m³) at 1.5mAG (Operational Phase)

Figure 3.16 Contour of Cumulative 4^th Highest Daily SO₂ Concentration (µg/m³) at 15.0mAG (Operational Phase)

Figure 3.17 Contour of Cumulative 19^th Highest Hourly NO₂ Concentration (µg/m³) at 5.0mAG (Operational Phase)

Figure 3.18 Contour of Cumulative Annual NO₂ Concentration (µg/m³) at 5.0mAG (Operational Phase)

Figure 3.19 Contour of Cumulative Annual NO₂ Concentration (µg/m³) at 10.0mAG (Operational Phase)

APPENDICES

Appendix 3.1 Calculation of Construction Dust Emission Source

Appendix 3.2 Determination of Surface Characteristics Parameters

Appendix 3.3 Traffic Forecast for Air Quality Impact Assessment

Appendix 3.4 EMFAC-HK Model Assumptions

Appendix 3.5 Composite Vehicular Emission Factors for CALINE4 Model

Appendix 3.6 Detailed Calculation of Emissions from Tunnel Portals and Ventilation Building

Appendix 3.7 Detailed Calculation of Emissions Associated with Public Transport Interchanges, Bus Termini, Heavy Goods Vehicle Parking Site and Kiosks

Appendix 3.8 Detailed Calculation of Emissions from Marine Vessels

Appendix 3.9 Cumulative Results for Construction Dust Impact Assessment

Appendix 3.10 Jenkin Method for Long-term Cumulative NO₂ Assessment

Appendix 3.11 Cumulative Results for Operational Air Quality Impact Assessment

3 AIR QUALITY

3.1 Introduction

3.1.1.1 The Project comprises (i) a proposed Airport Tung Chung Link (ATCL) to connect HKP Island, Airport Island and Tung Chung Town Centre via a road link; and (ii) marine facilities in the waters between Airport Island and HKP Island.

3.1.1.2 The potential air quality impacts during the construction phase of the ATCL are associated with fugitive dust emissions during heavy construction activities including site clearance, utilities protection, slope work, excavation, piling and roadworks, site formation, etc., wind erosion of exposed work area, and exhaust emission from construction plant and equipment, construction vehicles and construction vessels. As the construction of the proposed marine facilities will involve marine-based construction activities, fugitive dust emission is unlikely generated from marine-based construction activities. However, exhaust emission from construction vessel involving construction of floating platforms, wave attenuator, fixed ramp and gangway, etc., may pose potential impact on nearby ASRs. In addition to marine-based construction activities of the proposed marine facilities, there is some land-based construction activities, including site clearance, site formation, construction of substructure, etc., of the ancillary blocks for berthing facilities and pier with area of approximately 540m². Cumulative impacts associated with dust emission anticipated at construction activities of the Project within the assessment area during the construction phase is also assessed.

3.1.1.3 In terms of operational impacts, the air pollutants emissions from the marine facilities would be the major source. As zero emission vehicles will be adopted for the autonomous transportation system of the Project, there will be no emission from the vehicles on the entire ATCL, the proposed depots and stations. Nonetheless, potential air quality impacts from marine vessels emission are anticipated at marine facilities. Cumulative impacts associated with marine vessel emissions anticipated at proposed marine facilities within the assessment area during the operational phase is also assessed. In order to widen the walkways on the side of Fu Tung Street eastbound, modification of road kerb of Fu Tung Street eastbound would be conducted while the road kerb of Fu Tung Street westbound will remain the same. Fu Tung Street will thus be narrower than the existing one. However, the modification work would not increase the traffic capacity of Fu Tung Street. Hence, additional air quality impact due to such modification is not anticipated during the operational phase.

3.2 Relevant Legislation and Guidelines

3.2.1 Background

3.2.1.1 The air quality impact assessment criteria shall make reference to the Air Pollution Control Ordinance (APCO) (Cap. 311) and Annex 4 of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM).

3.2.2 Air Quality Objectives

3.2.2.1 The APCO provides a regulatory framework for controlling air pollutants from a variety of stationary and mobile sources and encompasses a number of Air Quality Objectives (AQOs).

3.2.2.2 The prevailing AQOs represent the current policy of the Government as regards the acceptable levels of air pollutants having taken into account a number of factors including public health.

3.2.2.3 The prevailing AQOs are benchmarked against a combination of interim and ultimate air quality targets in the World Health Organisation Air Quality Guidelines (WHO Guidelines) which are promulgated for protection of public health.

3.2.2.4 The AQOs stipulate concentrations for a range of pollutants namely sulphur dioxide (SO2), respirable suspended particulates (PM10), fine suspended particulates (PM2.5), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3) and lead (Pb). The AQOs implemented in Jan 2022 are shown in Table 3.1.

Table 3.1 Hong Kong Air Quality Objectives

Pollutant	Averaging time	Concentration Limit^[i] (μg/m^3)	Number of Exceedances allowed
Sulphur Dioxide (SO2)	10-minute	500	3
	24-hour	50	3
Respirable Suspended Particulates (RSP/PM10)^[^ii]	24-hour	100	9
	Annual	50	Not applicable
Fine Suspended Particulates (FSP/PM2.5)^[^iii]	24-hour	50	35
	Annual	25	Not applicable
Nitrogen Dioxide (NO2)	1-hour	200	18
	Annual	40	Not applicable
Ozone (O3)	8-hour	160	9
Carbon Monoxide (CO)	1-hour	30,000	0
	8-hour	10,000	0
Lead (Pb)	Annual	0.5	Not applicable

Note:

[i] All measurements of the concentration of gaseous air pollutants, i.e., sulphur dioxide, nitrogen dioxide, ozone and carbon monoxide, are to be adjusted to a reference temperature of 293 Kelvin and a reference pressure of 101.325kPa.

[ii] Respirable suspended particulates mean suspended particles in air with a nominal aerodynamic diameter of 10μm or less.

[iii] Fine suspended particulates mean suspended particles in air with a nominal aerodynamic diameter of 2.5μm or less.

3.2.3 EIAO-TM

3.2.3.1 Annexes 4 and 12 of the EIAO-TM set out the criteria and guidelines for evaluating air quality impacts, respectively.

3.2.4 Air Pollution Control (Construction Dust) Regulation

3.2.4.1 The Air Pollution Control (Construction Dust) Regulation specifies processes that require special dust control. The Contractors are required to inform EPD and adopt proper dust suppression measures while carrying out “Notifiable Works” (which requires prior notification by the regulation) and “Regulatory Works” to meet the requirements as defined under the regulation.

3.2.5 Air Pollution Control (Non-road Mobile Machinery) (Emission) Regulation

3.2.5.1 The Air Pollution Control (Non-road Mobile Machinery) (Emission) Regulation comes into operation on 1 June 2015. Under the Regulation, non-road mobile machinery (NRMMs), except those exempted, are required to comply with the prescribed emission standards. From 1 September 2015, all regulated machines sold or leased for use in Hong Kong must be approved or exempted with a proper label in a prescribed format issued by EPD. Starting from 1 December 2015, only approved or exempted NRMMs with a proper label are allowed to be used in specified activities and locations including construction sites. The Contractor is required to ensure the adopted machines or non-road vehicle under the Project could meet the prescribed emission standards and requirement.

3.2.6 Air Pollution Control (Fuel Restriction) Regulation

3.2.6.1 The Air Pollution Control (Fuel Restriction) Regulation was enacted in 1990 and amended in 2008. The regulation imposes legal control on the type of fuels allowed for use and their sulphur contents in commercial and industrial processes. Gaseous fuel, conventional solid fuel with a sulphur content not exceeding 1% by weight or liquid fuel with a sulphur content of not more than 0.005% by weight and a viscosity not more than 6 centistokes at 40^oC, such as Ultra Low Sulphur Diesel (ULSD) are permitted to be used in commercial and industrial processes.

3.3 Existing Environment

3.3.1 Background

3.3.1.1 The Project is to construct and operate (i) the Airport Tung Chung Link (ATCL) to connect Hong Kong Port (HKP) Island and Tung Chung Town Centre via a road link and (ii) marine facilities in the waters between Airport Island and HKP Island.

3.3.1.2 The existing air sensitive receivers (ASRs) in the assessment area comprise mainly of commercial uses and the uses for government, institution or community.

3.3.2 Identification of Ambient Air Quality

3.3.2.1 The nearest Air Quality Monitoring Station (AQMS) operated by EPD in the proximity of the Project is the Tung Chung AQMS located at Tung Chung Health Centre which is approximately 250m northeast of the Project. The latest 5-year air quality data from this station (i.e. 2017 to 2021), are summarised in Table 3.2

3.3.2.2 to show the trend in air quality.

Table 3.2 EPD Air Quality Monitoring Data at Tung Chung AQMS (2017 – 2021)

Pollutant	Averaging Period	AQO ^(1)µg/m^3	Concentration (µg/m^3)
			2017	2018	2019	2020	2021
SO2	10-mins 4^th Highest	500[3]	87	88	57	24	19
	24-hours 4^th Highest	50[3]	21	19	18	8	9
RSP / PM10	24-hours 10^th Highest	100[9]	81	73	75	66	63
	Annual	50	34	31	30	25	26
FSP / PM2.5	24-hours 36^th Highest	50[35]	42	33	35	27	31
	Annual	25	21	18	19	14	17
NO2	1-hour 19^th Highest	200[18]	144	156	149	113	115
	Annual	40	36	33	33	28	26
CO	1-hour 1^st Highest	30,000	1810	1780	2260	1530	1240
	8-hour 1^st Highest	10,000	1544	1353	1874	1388	1073
O3	8-hour 10^th Highest	160[9]	187	173	208	168	158

Note:

(1) Numbers in brackets [ ] denote the number of exceedances allowed.

(2) Monitoring results exceeding the prevailing AQOs are shown as bold and underlined characters.

3.3.2.3 As shown in Table 3.2 the historical background concentrations for 10-min SO₂, daily SO₂, daily RSP, annual RSP, daily FSP, annual FSP, hourly NO₂, annual NO₂, hourly CO and 8-hour CO complied with their respective AQOs (i.e. prevailing AQOs with effect from 1 January 2022) in Years 2017 to 2021. For the historical 8-hour Ozone levels, the corresponding AQO was exceeded in 2017 to 2020 but was in compliance in 2021.

3.3.2.4 There are three other AQMSs operated by AAHK in vicinity of the Project, including Sha Chau Station, North Station and South Station. The stations are located north of the airport, northeast and southwest of the airport, respectively. The latest 5-year air quality monitoring data from these stations (i.e. 2017 to 2021) are summarised in Table 3.3, Table 3.4 and Table 3.5 to show the trend in air quality. The locations of the AAHK AQMSs are shown in Figure 3.1.

Table 3.3 AAHK Air Quality Monitoring Data at Sha Chau Station (2017 – 2021)

Pollutant	Averaging Period	AQO ^(1)µg/m^3	Concentration (µg/m^3)
			2017	2018	2019	2020	2021
SO2	10-mins 4^th Highest	500[3]	242	173	49	46	55
	24-hours 4^th Highest	50[3]	33	24	11	9	10
RSP / PM10	24-hours 10^th Highest	100[9]	72	77	99	89	78
	Annual	50	35	39	47	42	26
FSP / PM2.5	24-hours 36^th Highest	50[35]	38	35	44	36	29
	Annual	25	24	23	28	23	15
NO2	1-hour 19^th Highest	200[18]	188	184	148	135	154
	Annual	40	37	36	33	28	28
CO	1-hour 1^st Highest	30,000	1675	2242	2372	2494	3223
	8-hour 1^st Highest	10,000	1611	1681	2163	1555	2184
O3	8-hour 10^th Highest	160[9]	242	226	150	210	228

Note:

(1) Numbers in brackets [ ] denote the number of exceedances allowed.

(2) Monitoring results exceeding the prevailing AQOs are shown as bold and underlined characters.

Table 3.4 AAHK Air Quality Monitoring Data at North Station (2017 – 2021)

Pollutant	Averaging Period	AQO ^(1)µg/m^3	Concentration (µg/m^3)
			2017	2018	2019	2020	2021
SO2	10-mins 4^th Highest	500[3]	177	178	56	57	47
	24-hours 4^th Highest	50[3]	20	17	12	11	12
RSP / PM10	24-hours 10^th Highest	100[9]	73	76	83	80	76
	Annual	50	46	40	42	34	32
FSP / PM2.5	24-hours 36^th Highest	50[35]	30	32	34	29	29
	Annual	25	28	21	22	19	16
NO2	1-hour 19^th Highest	200[18]	191	207	150	134	149
	Annual	40	51	44	40	35	39
CO	1-hour 1^st Highest	30,000	1730	2407	2275	2653	3423
	8-hour 1^st Highest	10,000	1542	1857	1925	1577	1771
O3	8-hour 10^th Highest	160[9]	193	190	243	203	175

Note:

(1) Numbers in brackets [ ] denote the number of exceedances allowed.

(2) Monitoring results exceeding the prevailing AQOs are shown as bold and underlined characters.

Table 3.5 AAHK Air Quality Monitoring Data at South Station (2017 – 2021)

Pollutant	Averaging Period	AQO ^(1)µg/m^3	Concentration (µg/m^3)
			2017	2018	2019	2020	2021
SO2	10-mins 4^th Highest	500[3]	239	149	61	65	199
	24-hours 4^th Highest	50[3]	24	20	14	12	12
RSP / PM10	24-hours 10^th Highest	100[9]	81	73	71	70	53
	Annual	50	39	41	34	31	19
FSP / PM2.5	24-hours 36^th Highest	50[35]	34	30	28	26	25
	Annual	25	22	22	17	16	13
NO2	1-hour 19^th Highest	200[18]	166	167	152	121	128
	Annual	40	52	51	46	38	41
CO	1-hour 1^st Highest	30,000	1662	1876	2433	1725	1714
	8-hour 1^st Highest	10,000	1469	1565	2048	1625	1520
O3	8-hour 10^th Highest	160[9]	215	178	230	195	180

Note:

(1) Numbers in brackets [ ] denote the number of exceedances allowed.

(2) Monitoring results exceeding the prevailing AQOs are shown as bold and underlined characters.

3.3.3 Future Background Air Quality

3.3.3.1 In order to predict the future background air pollutant concentrations within the assessment area, hourly background concentrations of NO₂, PM₁₀, PM_2.5, SO₂, O₃ and CO have been extracted from the EPD’s Pollutants in the Atmosphere and their Transport over Hong Kong (PATH v2.1). The assessment area covers PATH grids (16,30), (16,31), (16,32), (16,33), (17,30), (17,31), (17,32), (17,33), (18,32) and (18,33), which are shown in Figure 3.1.

3.3.3.2 Table 3.6 summarized the background levels from the PATH model against the existing AQOs. Year 2025 data from PATH v2.1 are adopted in the assessment as background concentrations.

Table 3.6 Future Background Air Quality from PATH v2.1 for Year 2025

Pollutant	Averaging Period	AQO ^(1)µg/m^3	Value at relevant PATH Grid (µg/m^3)^(^4)
			16,30	16,31	16,32	16,33	17,30	17,31	17,32	17,33	18,32	18,33
SO2	4^th Highest 10-mins	500[3]	101	104	108	118	92	103	91	100	112	126
	4^th Highest 24-hours	50[3]	16	19	20	17	14	16	17	15	15	15
RSP/ PM10	10^th Highest 24-hours	100[9]	66	67	68	67	67	67	67	68	68	68
	Annual	50	26	28	28	28	27	28	28	29	28	29
FSP/ PM2.5	36^th Highest 24-hours	50[35]	24	24	25	25	24	24	24	25	24	25
	Annual	25	15	15	15	15	15	15	15	16	15	16
NO2	19^th Highest 1-hour	200[18]	126	128	135	132	124	125	126	129	125	128
	Annual	40	19	23	28	30	19	22	26	30	27	31
CO	1^st Highest 1-hour	30,000	919	926	1129	975	931	935	935	929	948	943
	1^st Highest 8-hour	10,000	856	865	873	868	861	871	875	876	897	899
O3	10^th Highest 8-hour	160[9]	229	228	229	230	230	233	235	225	223	219

Note:

(1) Numbers in brackets [ ] denote the number of exceedances allowed

(2) Conversion factors were referenced from the “EPD’s Guidelines on the Estimation of 10-minute Average SO₂ Concentration for Air Quality in Hong Kong” to convert the 1-hr average concentration of SO₂

(3) The PATH background air pollutant concentrations as presented in the table above do not included the Tier 1&2 emission sources yet.

(4) Exceedance of relevant AQOs are shown as bold and underlined characters.

3.3.3.3 As show in Table 3.6 , the future background levels of hourly and annual NO₂, daily and annual RSP and FSP, 10-min and daily SO_2, and hourly and 8-hour CO predicted by the PATH model would be below the relevant AQOs. Exceedances of the 10^th highest 8-hour O₃ were predicted in Year 2025. The improvement in future ambient air quality can be attributed to the government’s commitment to implement various planned emission reduction measures, as published on EPD’s website (http://www.epd.gov.hk/epd/english/environmentinhk/air/prob_solutions/strategies_apc.html).

3.4 Identification of Air Sensitive Receivers

3.4.1.1 The representative Air Sensitive Receivers (ASRs) for construction dust impact assessment are identified within an assessment area of 500m from the boundary of the Project and shown in Figure 3.2. With the adoption of zero emission vehicle, the potential operational air quality impacts related mainly to marine vessel emission. As such, the representative ASRs for operational air quality impact assessment are identified within an assessment area defined as by a distance of 500m from the boundary of proposed marine facilities and shown in Figure 3.3.

3.4.1.2 Existing and planned ASRs within the assessment area have been identified with reference to the latest information provided on the survey maps, topographic maps, aerial photos and land status plans.

3.4.1.3 According to the Approved Chek Lap Kok Outline Zoning Plan (OZP) No. S/I-CLK/16, the Approved Tung Chung Town Centre Area OZP No. S/I-TCTC/24 and other published plans in the vicinity of the Project, the existing ASRs are uses of Government, Institution or Community (GIC), other specific uses (OU), commercial uses (C) and open space (O) etc. Details of the identified representative ASRs for construction dust impact assessment and operational air quality impact assessment are summarized in Table 3.7.

Table 3.7 Representative Air Sensitive Receivers

ASR ID	Description	Use ^[1]	Approximate Separation Distances of ASRs from the Nearest Emission Sources (m)	Approximate Building Height (mAG)	Assessment Height (mAG)	Construction Dust Impact Assessment	Operational Air Quality Impact Assessment
Existing
A01	Offices at Hong Kong Port (HKP) Passenger Crossing Building (PCB)	O	370	30.9	Note [2]	ü	ü
A02	East Sea Rescue Berth Airport Fire Contingent	O	480	6.2	Note [2]	ü	ü
A03	AsiaWorld-Expo	C	435	22.1	Note [2]	ü	ü
A04	Hong Kong SkyCity Marriott Hotel	H	215	44.7	Note [2]	ü	ü
A05	Regala SkyCity Hotel	H	295	46.5	Note [2]	ü	ü
A06	SkyPier	O	100	15	Note [2]	ü	ü
A07	CNAF HK Refuelling Limited	O	375	5	Note [2]	ü
A08	Civil Aviation Department Headquarters	O	110	19.3	Note [2]	ü
A09	Cathay Dragon House	O	55	19.3	Note [2]	ü
A10	CNAC House	O	85	27.1	Note [2]	ü
A11	Hong Kong Airlines Training Academy	O	170	46.2	Note [2]	ü
A12	Cathay City	O	220	41	Note [2]	ü
A13	Ancient Kiln Park	Rec	150	N/A	Note [2]	ü
A14	Seaview Crescent	R	200	162.9	Note [2]	ü
A15	Man Tung Road Park	Rec	80	N/A	Note [2]	ü
A16	Novotel Citygate Hong Kong	C	85	86.3	Note [2]	ü
A17	Tung Chung Municipal Service Building	O	185	13.8	Note [2]	ü
A18	Ling Liang Church E Wun Secondary School	E	300	30	Note [2]	ü
A19	Ling Liang Church Sau Tak Primary School	E	395	29.2	Note [2]	ü
A20	Tung Chung Community Garden	Rec	45	3.6	Note [2]	ü
A21	One Citygate	C	10	16.8	Note [2]	ü
A22	Fu Tung Plaza	C	105	10.9	Note [2]	ü
A23	Tung Chung Health Centre	M	250	16	Note [2]	ü
A24	Ching Chung Hau Po Woon Primary School	E	285	21.2	Note [2]	ü
A25	Po On Commercial Association Wan Ho Kan Primary School	E	300	21.3	Note [2]	ü
A26	Tung Chung Swimming Pool	Rec	290	9	Note [2]	ü
A27	Tung Chung Crescent	R	170	127.1	Note [2]	ü
A28	Fu Tung Estate	R	220	85.7	Note [2]	ü
A29	Yu Tung Court	R	245	80.6	Note [2]	ü
Planned / Under Construction
P01^[3][4]	Campus and Dormitory of the Hong Kong International Aviation Academy	E / R	150	26	Note [2]	ü
P02^[3]	Offices SkyPier Terminal	O	30	46.6	Note [2]	ü	ü
P03^[3]	11 SKIES	C	105	46.7	Note [2]	ü	ü
P04^[3]	Planned Commercial Use	C	0	43.9	Note [2]	ü	ü
P05^[3][4]	Planned Visitation Church Development	W	5	26.2	Note [2]	ü

Notes:

[1] W: Place of Public Worship; C: Commercial; M: Clinic/Medical Centre; H: Hotel; O: Office; E: Educational Institutions; Rec: Park/Recreational; R: Residential

[2] The impact on ASRs at 1.5mAG, 5mAG, 10mAG, 15mAG, 20mAG and from 20mAG to the maximum height at interval of 10m would cover the worst hit level.

[3] Information of description and use are provided by AAHK, while building heights of the relevant developments are made reference to the approved Chek Lap Kok Outline Zoning Plan (S/I-CLK/16). As advised by AAHK, the tentative occupation years for P01, P02, P03 and P05 are 2025, 2023, 2023 and 2026, respectively (the construction period of the Project from Year 2025 to 2028). As the estimated occupation year for P04 is not available, P04 was considered as ASRs during the construction and operation of the Project for a conservative approach.

[4] ASRs P01 and P05 are outside the assessment area for operational air quality impact assessment.

3.5 Construction Dust Impact Assessment

3.5.1 Identification of Potential Air Quality Impacts and Representative Pollutants

General

3.5.1.1 The construction phase air quality impacts arising from the Project have been assessed according to the EIA Study Brief (ESB-342/2021).

3.5.1.2 According to Clause 3.4.4.2 of the EIA Study Brief (ESB-342/2021), the assessment area for air quality impact assessment shall be defined by a distance of 500m from the boundary of the Project area and the works of Project as identified in the EIA study, which shall be extended to include major existing, committed and planned air pollutant emission sources identified to have a bearing on the environmental acceptability of the Project. An assessment area of 500m from the boundary of the Project are shown in Figure 3.2.

3.5.1.3 In order to evaluate the cumulative air quality impacts during construction phase of the Project, projection of future year background air quality levels was extracted from the “Pollutant in the Atmosphere and the Transport over Hong Kong” (PATH) model released by EPD. In the PATH model, all major emission sources including public electricity generation, civil aviation, road transport, navigation, industries, other fuel combustion and non-combustion sources covering both HKSAR and Pearl River Delta Economic Zone (PRDEZ) are considered. In addition, major point sources located within 4km from the Project shall be simulated by dispersion model to account for their induced sub-grid scale spatial variations in background air quality.

Project induced Contribution

3.5.1.4 As mentioned in Sections 3.1.1.2and 3.1.1.3, the construction works will involve land-based and marine-based construction activities. Land-based construction activities will involve site clearance, utilities protection, slope work, excavation, piling and roadworks, site formation, construction of aboveground structures and buildings for the proposed marine facilities, etc., which will lead to fugitive dust emission, which have been considered in the quantitative impact assessment as heavy construction activities. In addition, there will be minor land-based construction activities of the reprovision and diversion works, including widening of walkways, reprovision of cycle track, modification of road kerb, reprovision of road marking, utilities diversion works, that would be carried out in Tung Chung Area. The reprovision and diversion works would be divided into multiple working sections and be carried out section by section. The construction activities at each section would not be undertaken at the same time. The construction activities of the reprovision and diversion works at each section would be small-scale and confined in a small work area of approximately 150m². Hence, the active exposed work site would be limited. The reprovision and diversion works will involve minor excavation with backfilling. The amount of the daily excavated materials arising from the reprovision and diversion works is estimated to be approximately 23m³, of which approximately 96% will be reused on-site for backfilling materials. Due to the small amount of excavated materials to be disposed of off-site, the dust generated from construction vehicles for materials handling would generally be limited within the work areas. With the implementation of good site practices and mitigation measures stipulated in the Air Pollution Control (Construction Dust) Regulation, dust emission from the relevant works would be well controlled and minimised, and hence not considered in the quantitative assessment.

3.5.1.5 Marine-based construction activities are unlikely to generate fugitive dust due to high moisture content of handling materials and hence not considered in the quantitative assessment. In addition to fugitive dust impact, the induced vehicular and marine traffic during construction phase has also been considered in the quantitative impact assessment.

3.5.1.6 Construction vehicles, including dump trucks for construction material delivery and concrete lorry mixers, would be required during the construction period and the traffic flow of construction vehicle would be approximately 30 trips/hr during the peak construction period. The tentative transporting routings are:

· From / To Proposed Marine Facilities: Tuen Mun - Chek Lap Kok Link, Chek Lap Kok Road, Sky City Road East

· From / To ATCL (North Portion): Tuen Mun - Chek Lap Kok Link, Chek Lap Kok Road, East Coast Road, Kwo Lo Wan Road

· From / To ATCL (South Portion): North Lantau Highway, Tung Chung Waterfront Road, Chek Lap Kok South Road, Kwo Lo Wan Road

3.5.1.7 In order to minimize the duration of transportation, the travelling distance of the dump trucks and concrete lorry mixers would be minimised and the use of highways would be maximised. In addition, the transportation routes would be selected away from ASRs as far as practicable and the dump trucks would be covered by clean impervious sheeting to minimize dust nuisance to the nearby ASRs. Therefore, no adverse dust emission induced by the construction vehicles to the surrounding ASRs is anticipated with implementation of mitigation measures stipulated in the Air Pollution Control (Construction Dust) Regulation.

3.5.1.8 In addition to construction vehicle, construction vessels for delivering construction materials would be required during the construction phase of the Project due to the site constrains and the availability of the works space for the construction works. The construction materials will be delivered by barges. Tugboat would be used to haul the barge. Furthermore, workboats would be adopted as passenger boat for workers and patrol boat.

3.5.1.9 For ATCL, the construction vessels will be involved in the works of marine viaduct, including construction of bored piles, pile cap and pier construction, and bridge deck, and the other works along the east coast of Airport Island, including removing armour rocks, placing concrete blocks, and material delivery. The construction vessels will also be involved in the works of proposed berthing facilities and pier, including installation of socket H-pile and casing, wave attenuator, floating pier and floating pontoons / walkways / gangway.

3.5.1.10 The construction vessels to the works area of marine viaduct would be from the west of Tung Chung Navigation Channel, while the construction vessels to the works areas along the east coast of Airport Island would be from the east of Tung Chung Navigation Channel. It is estimated that the marine traffic activity of construction vessels entering/exiting each works area would be approximately 12 - 16 vessel trips per day. The hotelling time is assumed to be approximately 30min per hour per each tugboat for assisting the construction works and approximately 5min per trip per each workboat.

Dust Emission from Concurrent Construction Projects

3.5.1.11 The construction period of the Project is tentatively scheduled to commence in the 4^th quarter of 2025 and for completion by the end of 2028. As mentioned in Section 2.10, all potential concurrent projects have been identified. Concurrent construction projects were identified within 500m from the Project, which will have potential cumulative construction dust impact. Appendix 3.1 shows the locations of the concurrent projects.

Tung Chung Line Extension (TCLE)

3.5.1.12 According to the approved EIA Report (AEIAR-235/2022) for TCLE, the construction period of this Project will be tentatively from Year 2023 to Year 2029. The heavy and dusty construction activities will be completed in Year 2027. Hence, potential cumulative construction dust impact from its concurrent construction with the Project is anticipated and is included in the quantitative assessment.

Tung Chung New Town Extension (TCNTE)

3.5.1.13 According to the Approved TCNTE EIA Report (Register No.: AEIAR-196/2016), the worksites of Tung Chung West and East of Tung Chung New Town Extension are outside 500m assessment area of the Project, and hence are excluded in the quantitative assessment.

Commercial Developments at East Coast Support Area (ECSA) and Developments of Airport-related Supporting Uses at HKP Island

3.5.1.14 As advised by the Project Proponent of commercial developments of ECSA and developments of airport-related supporting uses at HKP island, Hong Kong Airport Authority, the developments will be completed in phases. Construction works of developments mainly involve site clearance and formation, building footprint excavation, construction of superstructure, etc. For conservative approach, the dust emission induced by commercial developments of ECSA and developments of airport-related supporting uses at HKP island within the assessment area of the Project are included in the quantitative assessment.

Planned Visitation Church Development

3.5.1.15 The church is located next to the TCC Station of the ATCL. The site area of planned Visitation Church Development is approximately 0.22 hectare. According to the best available information provided by AAHK, the tentative construction works of the church are targeted to commence in early 2023 for completion in early 2026. The major dusty works for the church including site formation, excavation and foundation works are expected to be completed before the commencement of the construction of the Project. The construction works, including superstructure and fitting-out works, of the church would be overlapped with the Project from late 2025 to early 2026. As only minor superstructure and fitting-out works of the church are expected in the overlapping period, the construction dust impact from this development would be limited. Therefore, adverse cumulative impacts with this development are not anticipated and construction dust impact from the church is excluded in the quantitative assessment.

Other Major Pollution Emissions in the Immediate Neighbourhood

3.5.1.16 Particulate emissions, including TSP, RSP and/or FSP, would also be generated from pollutant-emitting activities in the immediate neighbourhood and other contributions from pollution not accounted for construction activities, all of which would contribute to the cumulative impacts. They include (1) vehicular emission from open roads, (2) vehicular emission from tunnel portals and ventilation building, (3) emission from public transport interchanges / bus termini / heavy goods vehicle parking site, (4) emission from idling vehicles at kiosks of HKP Island, and (5) marine emission from ferries travelling between Tuen Mun, Tung Chung and Tai O / ferries travelling between SkyPier and Macau / Pearl River Delta (PRD). No industrial chimney was identified within the assessment area.

Vehicular Emission from Open Roads

3.5.1.17 Potential vehicular emission would be generated from all existing and planned road network and the induced traffic from the planned/committed projects, such as Tung Chung New Town Extension (TCNTE), SKYCITY Developments, Three Runway System of Hong Kong International Airport, etc.

3.5.1.18 According to the approved EIA report (AEIAR-216/2018) for Intermodal Transfer Terminal – Bonded Vehicular Bridge and Associated Roads (ITT), only electric vehicles will be used on the SkyPier Terminal Bonded Bridge (formerly known as ITT) under normal circumstances. There will be no air pollutants emission during the operation of SkyPier Terminal Bonded Bridge. With reference to the Project Profile (PP-606/2020) submitted for Applications for Permission to Apply Directly for an Environmental Permit for Airport City Link, only electric vehicle will be used for the shuttle services and thus there will be no air pollutants emission during the operation of ACL (formerly known as Airport City Link).

3.5.1.19 The road network within the assessment area of 500m from the Project boundary are shown in Appendix 3.3.

Emission from Tunnel Portals and Ventilation Building

3.5.1.20 Emission from the tunnel portals and ventilation building would also cause cumulative air quality impact. They include:

· Scenic Hill Tunnel – Northbound and Southbound tunnel portals;

· Scenic Hill Tunnel – Ventilation building; and

·  HKP to Airport Tunnel – Tunnel portal only.

3.5.1.21 Emission split between ventilation building and tunnel portals, exit temperature, discharge velocity, exhaust diameter and height have been made reference to the approved EIA Report (AEIAR-144/2009) for Hong Kong - Zhuhai - Macao Bridge Hong Kong Link Road. The locations of tunnel portals and ventilation building within the assessment area of 500m from the Project boundary are shown in Appendix 3.6.

Emission from Idling Vehicles at Kiosks of HKP Island

3.5.1.22 Vehicular emission from idling vehicles at kiosks at HKP Island would have cumulative air quality impact on nearby ASRs. The locations of idling vehicles are shown in Appendix 3.7.

Emission from Public Transport Interchanges / Bus Termini / Heavy Goods Vehicle (HGV) Parking Site

3.5.1.23 4 existing PTIs / bus termini, 1 planned PTIs / bus termini and 1 existing HGV carpark have been identified within the assessment area of 500m from the Project boundary. Their locations are presented in Appendix 3.7. They include:

· Airport (Ground Transportation Centre) Bus Terminus;

· HZMB Hong Kong Port PTI;

· Tung Chung Temporary Bus Terminus;

· Tung Chung Station Bus Terminus;

· the Planned PTI at SKYCITY Site A3; and

· Tradeport Car/ Truck Park.

3.5.1.24 With reference to the latest Chek Lap Kok OZP, planned automated car parks at HKP Island will be located to the east of the Passenger Clearance Building. According to the design of the planned automated carpark provided by the operator, AAHK, the proposed automated car parks are proposed on the HKP Island to serve single-plate licensed private cars from Mainland and Macao, and to allow Mainland and Macao drivers to drive through the Hong Kong-Zhuhai-Macao Bridge (HZMB) and park their single-plate vehicles on the HKP Island. Automated parking system (APS), which will be operated by electricity, will be provided at these car parks. Under this system, vehicles will be transported by the system to designated spot during the whole parking and retrieving process. Engine will be turned off once the drivers enter the transfer cabin of the system.

3.5.1.25 As the proposed automated car parks only serve private cars, the start emission induced by the private cars using the automated car parks, which is relatively minor as compared with other vehicle types, would be included along local and rural roads with post speed of 50km/hr and the roads connecting to the parking sites.

3.5.1.26 In addition, AsiaWorld-Expo Bus Terminus will be decommissioned before the construction of the Project. Therefore, emission from AsiaWorld-Expo Bus Terminus is excluded in the quantitative assessment.

Emission from the Existing Marine Vessels

3.5.1.27 There are marine emissions from the existing passenger vessels at SkyPier, which provides ferry services for transit passengers from HKIA to nine ports in the Greater Bay Area and Macau. For the ferry activities of SkyPier, the schedule has been obtained from AAHK.

3.5.1.28 In addition to the ferry activities of SkyPier, marine emission from existing local vessels at the Tung Chung Development Pier for the transportation between Tuen Mun, Tung Chung, Sha Lo Wan and Tai O are also included in the cumulative assessment. The schedule has made referenced to the “Franchised and Licensed Ferry Service Details” published by the Transport Department (TD).

3.5.1.29 In view of the development of COVID-19 epidemic situation, the ferry services between Skypier and Macau / Skypier were suspended since 2020. The typical operational modes of the vessels were made reference to the “Study on Marine Vessels Emission Inventory” (MVEIS) issued by EPD on February 2012. A site survey on 28 September 2022 was conducted to confirm the typical operation mode of the existing local vessels at the Tung Chung Development Pier for the transportation between Tuen Mun, Tung Chung, Sha Lo Wan and Tai O.

3.5.1.30 Potential air quality impacts arising from the marine vessels would cause cumulative air quality impact and the locations of relevant marine routes are shown in Appendix 3.8.

Emission from Other Far-field Emission Sources

3.5.1.31 Other far-field emission sources outside the assessment area which would also have certain influence on the background air quality level include territory wide public electricity generation, civil aviation, road transport, navigation, industries, other fuel combustion and non-combustion sources as well as regional emission from the PRD. These sources are included in far-field modelling (i.e. the PATH model).

3.5.1.32 In order to account for the spatial variations in background concentration, major point sources within 4km from the identified ASRs have been reviewed. No major point source is identified within 4km from the identified ASRs.

Key Pollutants of Concern

3.5.1.33 Particulates from construction activities would be the major air pollutant during construction phase. Quantitative assessment of TSP emission impact as well as other particulates, RSP and FSP, would be conducted for assessing construction dust impact due to the Project.

3.5.1.34 Fuel combustion from the use of Powered Mechanical Equipment (PME) during construction works could be a source of NO₂, SO₂ and CO. In order to improve air quality and protect public health, EPD has introduced the Air Pollution Control (Non-road Mobile Machinery) (Emission) Regulation, which came in operation on 1 June 2015, to regulate emissions from machines and non-road vehicles. Starting from 1 December 2015, only approved or exempted non-road mobile machinery are allowed to be used in construction sites. The Air Pollution Control (Fuel Restriction) Regulation was enacted in 1990 and amended in 2008. According to the requirement stipulated in the Air Pollution Control (Fuel Restriction) Regulation, liquid fuel with a sulphur content of not more than 0.005% by weight should be adopted to minimise SO₂ emission from PME. Furthermore, good site practices presented in Section 3.5.4 are recommended to further control and reduce the emission from the use of non-road mobile machinery from the Project. Hence, the emissions from non-road mobile machinery are considered relatively small.

3.5.1.35 A relatively small number of construction vessels would be involved at each works area (i.e. approximately 12 - 16 vessel trips per day, of which 4 - 6 nos. are barge trips that are not propelled by an engine and hence no marine emission). The average number of construction vessels with engine at each works area would be approximately 1 - 2 trips per hour. Construction activities will not be concurrently undertaken at all works areas (the maximum number of concurrent works areas would be 6). Construction vessels would not concentrate at one works area, but distributing across different works areas of the Project (i.e. along the alignment of the ATCL and marine facilities). In addition, the travelling routes of construction vessels would be selected away from ASRs as far as practicable. In order to minmise the emission impact arising from the hoteling of construction vessels on nearby ASRs, the engine of the construction vessels would be switched off while the construction vessels do not involve in construction activities. According to the Air Pollution Control (Marine Light Diesel) Regulation, the sulphur content of locally supplied marine light diesel (MLD) used in marine vessels shall not exceed 0.05% by weight. Hence, the gaseous emissions (i.e. NO₂, SO₂ and CO) from the construction vessels are minimal and no adverse impact is anticipated.

3.5.2 Assessment Methodology

3.5.2.1 The assessment has evaluated the impacts arising from three classes of emission sources depending on their distance from the Project, including:

· Tier 1: Project induced contribution;

· Tier 2: Pollutant-emitting activities from concurrent construction projects and in the immediate neighbourhood; and

· Tier 3: Other contributions from pollution not accounted for by Tiers 1 and 2.

3.5.2.2 All sources within the assessment area of 500m (i.e. Tiers 1 and 2) are modelled using near-field dispersion models (i.e. CALINE4 and AERMOD) in accordance with “Guideline for Local Scale Air Quality Assessment Using Models” issued by EPD. These sources include (1) dust emission from the Project, marine emission (particulates) from construction vessels and vehicular emission from construction vehicles, (2) dust emission from concurrent construction projects, (3) vehicular emission (particulates) from open roads, (4) vehicular emission (particulates) from tunnel portals and ventilation building, (5) emission (particulates) from public transport interchanges / bus termini / heavy goods vehicle parking site, (6) emission from idling vehicles at kiosks of HKP Island and (7) marine emission (particulates) from ferries travelling between Tuen Mun, Tung Chung and Tai O / ferries travelling between SkyPier and Macau / PRD.

3.5.2.3 Impacts from other sources (Tier 3) beyond 500m from the Project (i.e. background concentration) are predicted using far-field dispersion model, –Pollutant in the Atmosphere and the Transport over Hong Kong, PATH. In the PATH model, all major emission sources including public electricity generation, civil aviation including emission from airport operation, road transport, navigation, industries, other fuel combustion and non-combustion sources covering both HKSAR and Pearl River Delta Economic Zone (PRDEZ) are considered.

Determination of the Assessment Year

3.5.2.4 According to Appendix B, Clause 5 (iv) of the EIA Study Brief for the Project, “For construction phase assessment, the Applicant shall demonstrate the use of the emission data of the future road traffic represents the highest emission scenario within the construction phase concerned”.

3.5.2.5 Particulate emission from the road traffic have been calculated based on the traffic data for the construction years (i.e. between 2025 and 2028) with emission factors for corresponding year to determine the highest emission strength from road vehicles within the construction years. The highest emission scenario is adopted in the construction dust impact assessment and selected as assessment year. For a conservative approach, construction activities are assumed to be concurrently undertaken at all works areas in the same year.

3.5.2.6 The traffic forecast data in Years 2025 and 2028 were provided by the Project Traffic Consultant, which was submitted to the TD. TD has no comments from a traffic engineering point of view on traffic data. Traffic forecast has been presented in Appendix 3.3. The vehicular emission factors of running and start exhaust for Years 2025 and 2028 were extracted from EMFAC-HK v4.3 in EMFAC mode with the representative data for temperature and relative humidity recorded at Chek Lap Kok Weather Station in Year 2021 obtained from Hong Kong Observatory (HKO). Start emissions of vehicles were distributed on local and rural roads with post speed of 50km/hr and the roads connected to the PTIs / bus termini / parking site with the number of trips for each vehicle class except FBDD, FBSD and PLB. It is assumed that the number of trips is directly proportional to VKT. Detailed assumptions and calculation adopted in the EMFAC-HK has been presented in Appendix 3.4.

3.5.2.7 According to the result presented in Appendix 3.4, Year 2028 has been selected as representing the worst-case year for construction dust impact assessment. As such, all modelling has used the emission factors from Year 2028 to determine the impacts on sensitive receivers.

Project induced Contribution

3.5.2.8 Construction dust impact was predicted based on emission factors from US Environmental Protection Agency (USEPA) Compilation of Air Pollution Emission Factors (AP-42), 5th edition and activity information from the engineer design. The heavy construction activities for the Project to be concerned and considered in the modelling assessment include site clearance, slope work, major excavation with backfilling, piling, roadworks and vehicular movements on haul road, etc.

3.5.2.9 Suitable dust size categories which are relevant to the concerned dust sources in this Project and with reasonable breakdowns in TSP, RSP and FSP compositions have been used in evaluating the impacts of dust-emitting activities. With reference to Section 13.2.4 of USPEA AP-42, TSP comprise 47.3% of particles with an aerodynamic diameter of <10μm (i.e. RSP) and 7.2% of particles with an aerodynamic diameter of <2.5μm (i.e. FSP). The emission factors for identified dust sources are estimated based on the relevant reference and summarised in Table 3.8. The detailed calculation of the emission rates and locations of emission sources are presented in Appendix 3.1.

Table 3.8 Key Dust Emission Factors Adopted in the Assessment

Activities	Emission Factors	Reference
Heavy construction activities including site clearance, slope work, major excavation with backfilling, piling and roadworks, vehicular movements on haul road, etc.	TSP Emission Factor = 2.69 Mg/hectare/month	USEPA AP-42, Section 13.2.3.3
	RSP Emission Factor = 2.69 x 47.3% Mg/hectare/month
	FSP Emission Factor = 2.69 x 7.2%Mg/hectare/month
Wind Erosion	E(TSP) = 0.85 Mg/hectare/year	USEPA AP-42, Section 11.9, Table 11.9-4
	E(RSP) = 0.85 x 47.3%Mg/hectare/year
	E(FSP) = 0.85 x 7.2% Mg/hectare/year

3.5.2.10 The assessment of construction dust impacts has been carried out based on the following conservative assumptions of general construction activities:

· Heavy construction activities are assumed to be concurrently undertaken at all works areas; and

· Wind erosion are assumed to be occurred at all active open sites and entire stockpile area.

3.5.2.11 Dust emission from heavy construction activities would be generated during the daytime between 07:00-19:00, 7 days a week in the assessment and only wind erosion is assumed for other non-working hours (19:00 to 07:00 of the following day).

3.5.2.12 In order to minimize the construction dust impact, regular watering on heavy construction work areas shall be implemented to reduce dust emission by 91.7%. Detailed calculation of the dust suppression efficiency is presented in Appendix 3.1.

3.5.2.13 The quantitative assessment of construction dust impacts has been conducted using AERMOD as approved by EPD, which is a computerised air quality model designed for computing the concentration and deposition impacts including fugitive dust sources.

3.5.2.14 Construction dust sources and wind erosion are modelled as “AREAPOLY” sources and are assumed operating during working hours (07:00 – 19:00) and non-working hours, respectively.

3.5.2.15 Dry deposition has been applied in the AERMOD for particulates. According to Section 13.2.4.3 of USEPA AP-42, the particle size distribution is assumed as 1.25μm, 3.75μm, 7.5μm, 12.5μm and 22.5μm with 7%, 20% 20%, 18% and 35% size distribution, respectively.

3.5.2.16 The Weather Research and Forecasting (WRF) meteorological data, including wind data, temperature, relative humidity, pressure, cloud cover and mixing height, for Year 2015 extracted from the PATH v2.1 released by EPD at the relevant grids (16,30), (16,31), (16,32), (17,30), (17,33) and (18,32) have been adopted for the corresponding ASRs (see Table 3.7). The minimum wind speed was capped at 1 metre per second. The meteorological data are inputted as on-site data into AERMET (version 22112).

3.5.2.17 Surface characteristic parameters such as albedo, Bowen ratio and surface roughness are required in the AERMET (the meteorological pre-processor of AERMOD). In accordance with USEPA’s AERSURFACE User’s Guide, albedo and Bowen ratio should be determined by 10km by 10km region. For surface roughness, the land use characteristics of each relevant PATH v2.1 grids (16,30), (16,31), (16,32), (17,30), (17,33) and (18,32) are classified into sectors by a default upwind distance of 1 km relative to the centre of PATH grids. The parameters of each sectors are then calculated by using default values suggested by USEPA’s AERSURFACE User’s Guide according to its land use characteristics. Adjusted friction velocity for low wind condition (ADJ_U*) option was applied in the AERMET. The detailed assumptions are presented in Appendix 3.2. The urban and elevated options in AERMOD were used in the model runs.

3.5.2.18 Dry deposition will be applied in the model run for particulates when appropriate. Particle size distribution will be also assigned for particles with aerodynamic diameters smaller than 10µm to each type of sources in the AERMOD in order to account for the particle deposition.

3.5.2.19 As mentioned in Section 3.5.1.7 to Section 3.5.1.9, construction vessels will be used to carry out the construction works between Year 2025 and 2028. Marine emission from these construction vessels might cause cumulative impact. Detailed assessment methodology of emission from construction vessels is the same as that of marine emission from marine vessels, which is discussed in Section 3.5.2.42 and Section 3.5.2.43. Apart from construction vessels, construction vehicles would be required during the construction period as mentioned in Section 3.5.1.5 and Section 3.5.1.6. The induced road traffic by the construction activities has been included in the traffic forecast data of open roads. The assessment methodology of vehicular emission from open roads are presented in Section 3.5.2.27 to Section 3.5.2.31.

Dust Emission from Concurrent Construction Projects

Tung Chung Line Extension (TCLE)

3.5.2.20 The cumulative construction dust impact from TCLE has been assessed based on the following same conservative assumptions for all assessment years in accordance with its approved EIA (AEIAR-235/2022):

· Heavy construction activities including site clearance, ground excavation, construction of the associated facilities, etc. to be concurrently undertaken at all works sites; and

· Wind erosion at all active works sites.

3.5.2.21 12-hour (07:00-19:00) per day, 7 days a week was assumed for the construction period in the assessment. Only wind erosion was assumed for other non-working hours (19:00 to 07:00 of the following day).

3.5.2.22 The same dust emission factors for heavy construction activities and wind erosion have been presented in Table 3.8. According to the approved EIA (AEIAR-235/2022), regular watering on all exposed construction areas with dust emission and haul road to achieve a dust removal efficiency of 91.7%.

Commercial Developments at East Coast Support Area (ECSA) and Developments of Airport-related Supporting Uses at HKP Island

3.5.2.23 The cumulative construction dust impact has been assessed based on the following conservative assumptions:

· Heavy construction activities including site clearance, ground excavation, construction of the associated facilities, etc. from all active works sites; and

· Wind erosion at all active works sites, entire stockpile area and spoils.

3.5.2.24 12-hour (07:00-19:00) per day, 7 days a week was assumed for the construction period in the assessment. Only wind erosion was assumed for other non-working hours (19:00 to 07:00 of the following day).

3.5.2.25 The same dust emission factors for heavy construction activities and wind erosion have been presented in Table 3.8. AAHK as the proponent of the ECSA, is committed and will request its work agent to carry out regular watering so as to achieve a dust removal efficiency of 91.7%. 

3.5.2.26 The detailed calculation of the emission rates and the locations of relevant dust emission sources of the concurrent projects are presented in Appendix 3.1.

Vehicular Emission from Open Roads

3.5.2.27 As mentioned in Section 3.5.2.7, the traffic forecast data in Year 2028 were adopted in the calculation of composite emission factors of open roads. Detailed assumptions and calculation have been presented in Appendix 3.4.

3.5.2.28 With reference to “Guidelines on Choice of Models and Model Parameters” issued by EPD, CALINE4, the near-field dispersion model developed by the California Department of Transport is used to assess vehicular emissions impact from all existing and planned open road network. The calculated 24-hour composite emission factors of 18 vehicle classes for each road link and locations of open roads considered in the assessment are presented in Appendix 3.5.

3.5.2.29 The WRF meteorological data extracted from the PATH model are adopted in CALINE4 model, including relevant temperature, wind speed, direction and mixing height. The mixing heights are capped between 131 metres and 1,941 metres according to the mixing height measured at King’s Park in Year 2015 by HKO. For the treatment of calm hours, the approach recommended in the "Guideline on Air Quality on Air Quality Models Version 05" is adopted. The minimum wind speed is capped at 1 metre per second.

3.5.2.30 The stability classes are estimated from the PCRAMMET model. The surface roughness height is closely related to the land use characteristics, and the surface roughness is estimated as 10 percent of the average height of physical structures within 1km study area. A surface roughness of 100cm is assumed to represent the low-rise developments and new development in the assessment area. The wind standard deviation is estimated in accordance with the “Guideline on Air Quality Models (Revised), 1986”.

3.5.2.31 Owing to the limitation of the CALINE4 model, elevated roads higher than 10m above local ground are set to the maximum height of 10m in the model as the worst-case assumption.

Emission from Tunnel Portals and Ventilation Building

3.5.2.32 The hourly emissions inside the tunnels have been calculated by multiplying the vehicular emission factors for Year 2028 obtained by the EMFAC-HK v4.3, by the traffic flow and the tunnel length. The traffic data was provided by the Project Traffic Consultant. “Technical Note on Traffic Forecast for Air Quality Impact Assessment” has been submitted to the TD and TD has no comments from a traffic engineering point of view on traffic data.

3.5.2.33 With reference to the approved EIA Report (AEIAR-144/2009) for Hong Kong - Zhuhai - Macao Bridge Hong Kong Link Road, it has been assumed that the emission spilt of Scenic Hill Tunnel would be 30% from tunnel portals and 70% from ventilation buildings. For emission from Tunnel of HKP to airport island, it has been assumed that the emission would be 100% from tunnel portals.

3.5.2.34 The AERMOD model, approved by the USEPA, is used to assess vehicular emissions from tunnel portals and ventilation buildings. Portal emissions are assumed to be discharged as a portal jet, with 2/3 of the total emission dispersed within first 50m from the portal and the remaining 1/3 within the second 50m in the direction of vehicular movement. To take into account the horizontal jet effect, portal emission is modelled as “Volume” source. Emissions from the ventilation buildings are modelled as “Point” Source in AERMOD.

3.5.2.35 The calculation of emission rates of the tunnel portals and ventilation building and the locations of emission sources are presented in Appendix 3.6.

Emission from Idling Vehicles at Kiosk of HKP Island

3.5.2.36 Emission is calculated based on the traffic data provided by the Project Traffic Consultant and warm idling emission factors from “Road Tunnels: Vehicle Emissions and Air Demand for Ventilation”. “Technical Note on Traffic Forecast for Air Quality Impact Assessment” has been submitted to the TD and TD has no comments from a traffic engineering point of view on traffic data. The calculation of the idling emission is presented in Appendix 3.7. AERMOD is adopted to assess the vehicular emission impact from idling vehicles at kiosk. Idling Emission is modelled as “Area” Source.

Emission from Public Transport Interchanges (PTIs) / Bus Termini / Heavy Goods Vehicle Parking Site

3.5.2.37 The vehicular emissions, including start, idling and running emissions from PTIs, bus termini, heavy goods vehicle parking site within the assessment area were calculated based on (i) the number of vehicle movement within each PTI, bus termini, heavy goods vehicle parking site, (ii) the estimated idling time and soaking time, (iii) the start and running emission factors predicted by EMFAC-HK model, (iv) the cold idling emission factors from the “Calculation of Start Emissions in Air Quality Impact Assessment” published by EPD, and (v) warm idling emission factors from “Road Tunnels: Vehicle Emissions and Air Demand for Ventilation” published by the Permanent International Association of Road Congresses (PIARC, 2019).

3.5.2.38 AERMOD is adopted to assess the vehicular emissions impact from start emissions, running exhaust emissions and idling emissions associated with the vehicles at the PTIs, Bus Termini, Heavy Goods Vehicle Parking Site. The emissions are modelled as “Area” and “Point” Sources.

3.5.2.39 The traffic data, idling time and soaking time of the PTIs, bus termini, heavy goods vehicle parking site were provided by the Project Traffic Consultant, while the number of trips are assumed to be the number of vehicles leaving PTIs, bus termini, heavy goods vehicle parking site. Relevant traffic data was provided by the Project Traffic Consultant. “Technical Note on Traffic Forecast for Air Quality Impact Assessment” has been submitted to the TD and TD has no comments from a traffic engineering point of view on traffic data.

3.5.2.40 Detailed calculation of the emissions and location of the sources are summarised in Appendix 3.7.

Emission from Marine Vessels

3.5.2.41 The marine emissions are estimated based on an activity-based approach. For the marine emission from ferry services at Skypier, the emission factors and different time-in-mode including hotelling, maneuvering and slow cruise have been made reference to the MVEIS. For the marine emission from the local vessels at the Tung Chung Development Pier, the emission factors have been made reference to the MVEIS, while different time-in-mode were estimated based on the site survey.

3.5.2.42 Marine vessel emissions have been modelled as numerous Horizontal “point” sources for marine vessels along the marine routes due to their high exhaust temperatures, exhaust velocities and release heights. The dispersion model AERMOD is adopted to assess the air pollutants concentrations of the exhaust emission of vessel engines. The emission of TSP has been assumed to be the same as that of RSP.

3.5.2.43 Detailed calculation of the marine emissions and locations of the sources are presented in Appendix 3.8.

Background Contribution

3.5.2.44 The PATH model has been used to predict far-field contributions to the background pollutant concentration levels on an hour-by-hour basis within the assessment area during the construction phase of the Project. Grids (16,30), (16,31), (16,32), (17,30), (17,33) and (18,32) are adopted as background levels for prediction of cumulative fugitive dust impact at the identified ASRs (see Table 3.7). The determined assessment year for construction dust impact assessment is Year 2028. As Year 2025 is the closest available year in PATH v2.1, the background RSP and FSP concentration levels for Year 2025 of relevant grids are extracted from the PATH model and adopted in assessment.

3.5.2.45 As the PATH model does not generate TSP results, the RSP concentration levels from PATH are taken to represent the background contributions to TSP at the sensitive receivers. This is considered to be a reasonable assumption as particulate matter of sizes larger than RSP from far-field sources would be largely settled before reaching the sensitive receivers. Therefore, the background hourly TSP levels can be reasonably estimated as the same as RSP concentrations for the purpose of estimating the cumulative 1-hour TSP levels due to the activities of the Project.

Cumulative Impacts

3.5.2.46 The predicted cumulative 1-hour TSP, and 24-hour and annual average concentrations of RSP and FSP are calculated based on the modelling results from Tier 1, Tier 2 and Tier 3. The predicted pollutant concentrations at ASRs will be compared with Annex 4 of EIAO-TM and the relevant AQOs to determine the compliance.

3.5.3 Cumulative Results

3.5.3.1 Table 3.9 below presents the predicted maximum 1-hour TSP concentration, 10th highest daily and annual average RSP, 36th highest daily and annual average FSP concentration at the representative ASRs based upon the worst case 100% active works area for the short-term predictions (1-hour and 24-hour) and for the annual predictions. The results include the cumulative impact from construction activities of the Project, vehicular emissions, marine emissions and background pollutant levels during construction phase. Cumulative results at the representative ASRs for construction dust impact assessment are presented in Appendix 3.9.

Table 3.9 Predicted Cumulative Concentrations of TSP, RSP and FSP at the Most Affected Assessment Levels of ASRs

ASR ID	Pollutant Concentration (µg/m^3)
	TSP	RSP		FSP
	Max. 1-Hourly Average	10^th Highest Daily Average	Annual Average	36^th Highest Daily Average	Annual Average
EIAO-TM / AQO	500	100	50	50	25
A01	148	69	31	26	16
A02	148	68	29	26	16
A03	148	69	30	26	16
A04	148	69	30	26	16
A05	148	69	30	26	16
A06	148	69	30	26	16
A07	150	70	31	26	17
A08	169	70	32	26	16
A09	198	75	36	26	17
A10	254	72	35	26	16
A11	182	70	32	25	16
A12	151	71	31	27	16
A13	153	70	31	26	16
A14	150	67	27	24	15
A15	153	67	28	24	15
A16	151	67	28	24	15
A17	151	67	27	24	15
A18	150	67	27	24	15
A19	150	67	27	24	15
A20	159	67	28	25	15
A21	150	68	28	25	16
A22	150	67	27	25	15
A23	150	67	27	25	15
A24	150	67	27	25	15
A25	150	67	27	25	15
A26	150	67	28	25	16
A27	167	66	27	24	15
A28	150	67	27	25	15
A29	149	67	27	25	15
P01	149	72	31	25	16
P02	148	69	30	26	16
P03	148	69	30	26	16
P04	148	69	30	26	16
P05	157	68	28	25	15

3.5.3.2 Based on the above results, the predicted pollutant concentrations at the representative ASRs are complying with the relevant AQOs and the criterion stipulated in EIAO-TM. Hence, no adverse air quality impact from the Project during the construction phase is anticipated.

3.5.3.3 Contour plots of maximum hourly TSP, 10^th highest daily average RSP, annual average RSP, 36^th highest daily average FSP and annual average FSP at 1.5mAG during the construction phase are presented in Figure 3.4, Figure 3.5, Figure 3.6, Figure 3.7 and Figure 3.8, respectively. With reference to the contour plots, there is no exceedance zone identified.

3.5.4 Good Site Practice and Recommended Mitigation Measures

3.5.4.1 Dust control requirements such as water spraying, compacting, vehicle washing facilities, etc. are required under APCO which will further limit the fugitive dust emissions from the land-based construction activities. With the implementation of sufficient dust control measures as stipulated under the APCO, Air Pollution Control (Construction Dust) Regulation (Cap. 311R) and good site practices, adverse dust impact from the construction activities of the Project is not anticipated.

3.5.4.2 The dust control measures detailed below shall also be incorporated into the Contract Specification where practicable as an integral part of good construction practice:

(i) Use of regular watering once per two hours to reduce dust emissions from all exposed site surfaces with dust emission and unpaved roads, particularly during dry weather;

(ii) Side enclosure and covering of any aggregate or dusty material storage piles to reduce emissions. Where this is not practicable owing to frequent usage, watering shall be applied to aggregate fines;

(iii) Open stockpiles shall be avoided or covered. Prevent placing dusty material storage piles near ASRs;

(iv) Tarpaulin covering of all dusty vehicle loads transported to, from and between site locations;

(v) Establishment and use of vehicle wheel and body washing facilities at the exit points of the site;

(vi) Imposition of speed controls for vehicles on unpaved site roads, 8km per hour is the recommended limit;

(vii) Routing of vehicles and position of construction plant should be at the maximum possible distance from ASRs;

(viii) Every stock of more than 20 bags of cement or dry pulverised fuel ash (PFA) should be covered entirely by impervious sheeting or placed in an area sheltered on the top and the 3 sides;

(ix) Cement or dry PFA delivered in bulk should be stored in a closed silo fitted with an audible high-level alarm which is interlocked with the material filling line and no overfilling is allowed; and

(x) Loading, unloading, transfer, handling or storage of bulk cement or dry PFA should be carried out in a totally enclosed system or facility, and any vent or exhaust should be fitted with an effective fabric filter or equivalent air pollution control system.

3.5.4.3 In addition to the dust control measures mentioned above, the following good site practices are recommended to further control and reduce the emission from the use of non-road mobile machinery from the Project:

· Regulated machines shall be used and exempted NRMMs should be avoided where practicable;

· Use of electric PMEs where practicable;

· Connect construction plant and equipment to main electricity supply and avoid using diesel generators and diesel-powered equipment as far as practicable;

· Switch off the engine of PMEs when idling;

· Implement regular and proper maintenance for plant and equipment;

· Employ plant and equipment of adequate size and power output and avoid overloading of the plant;

· Locate the PMEs away from sensitive receivers as far as possible; and

· Erect screen to shield the emission source from sensitive receivers where necessary and practicable.

3.5.5 Evaluation of Residual Impacts

3.5.5.1 With implementation of good site practice and recommended mitigation measures as described in Section 3.5.4, no adverse residual impact would be expected during the construction phase of the Project.

3.6 Operational Air Quality Impact Assessment

3.6.1 Identification of Potential Air Quality Impacts and Representative Pollutants

General

3.6.1.1 Potential air quality impacts from marine vessel emission are anticipated at proposed marine facilities. An assessment area for operational air quality impact assessment is defined by a distance of 500m from the boundary of proposed marine facilities and shown in Figure 3.3. Quantitative air quality impact assessment will be conducted to evaluate the cumulative air quality impact on nearby ASRs.

3.6.1.2 The key existing air pollution sources within the assessment area during operational phase include (1) vehicular emission from open roads, (2) emission from public transport interchanges / bus termini, (3) emission from idling vehicles at kiosks of HKP Island and (4) marine emission from ferries travelling between SkyPier and Macau / PRD. No industrial chimney was identified within the assessment area.

3.6.1.3 Specifically, the existing and potential near-field sources are described in the following sections below.

Project induced Emission

Autonomous Transportation System and Depot

3.6.1.4 Given that zero emission vehicles will be adopted for autonomous transportation system of the Project, no air quality impact is expected from the zero emission vehicles on the entire ATCL and station. The proposed depot will provide essential regular maintenance servicing for zero emission vehicles employed for the ATCL. The proposed depot is small-scaled and does not involve polluting process such as paint spraying and dry polishing activities. Major servicing will be carried out off-site by the zero emission vehicle supplier specialist services. The essential services of depot have been mentioned in Section 2.7.1.14. The key provision of the proposed depot is the vehicle maintenance workshop, which includes services bays, car lifts, brake testers, overheard crane, compressed air supply, vehicle repair hand tools, etc. Electrified equipment would be provided, hence, no gaseous and particulate emissions generated from exhaust emissions of the electrified equipment used for maintenance operations are expected. There will be NRMMs in the proposed depot. Air Pollution Control (NRMMs) (Emission) Regulation and Air Pollution Control (Fuel Restriction) Regulation shall be followed to control the fuel combustion emission from NRMMs. Exhaust emissions of NRMMs adopted for maintenance operations are expected to be limited. Thus, adverse air quality impact associated with any required maintenance works of zero emission vehicles at the depot is not anticipated.

Marine Emission from Proposed Marine Facilities

3.6.1.5 The proposed marine facilities will provide a pier and berthing facilities. The pier with two berths provides marine transport services associated with leisure and tourism. The pier will be managed by AAHK and/or its agent under pre-booking and pre-approval of services. As such, the frequency of marine traffic induced by pier will be limited. Incoming vessels will travel through the navigation channel and will make a turn to berth on one of assigned berth at finger pontoons. For planned pier, the pier is proposed to accommodate vessels to take passengers from the berthing facilities to tourist attractions in Hong Kong. The pier is estimated to generate 30 vessel trips per day (covering two-way trip).

3.6.1.6 The berthing facilities, with a maximum 73 numbers of berths, have been optimized to minimize environmental and marine traffic impact and cater for medium-to-small size pleasure vessels. An electricity pedestal will be installed at each berthing facility to provide on-shore power supply to vessels for reducing marine emissions at berth. Pleasure vessels are expected to stay overnight given the parking nature of the berthing facilities, projected to have a maximum berthing period of 1 month. The projected future peak marine traffic activity of pleasure vessels to/from the proposed berthing facilities is anticipated to be 44 vessel trips per day (covering two-way trip). In addition, the marine vessels using the berthing facilities will be required to turn off the engines when they are moored at the berthing facilities.

Other Emission Sources

Vehicular Emission from Open Roads

3.6.1.7 Potential vehicular emission would be generated from the existing and planned roads network and the induced traffic from the planned projects, such as SKYCITY Developments, Three Runway System of Hong Kong International Airport, etc.

3.6.1.8 According to the approved EIA report (AEIAR-216/2018) for Intermodal Transfer Terminal – Bonded Vehicular Bridge and Associated Roads (ITT), only electric vehicles will be used on the SkyPier Terminal Bonded Bridge (formerly known as ITT) under normal circumstances. There will be no air pollutants emission during the operation of SkyPier Terminal Bonded Bridge. With reference to the Project Profile (PP-606/2020) submitted for Applications for Permission to Apply Directly for an Environmental Permit for Airport City Link, only electric vehicle will be used for the shuttle services and thus there will be no air pollutants emission during the operation of ACL (formerly known as Airport City Link).

3.6.1.9 The road network within the assessment area of 500m from the proposed marine facilities are shown in Appendix 3.3.

Emission from Idling Vehicles at Kiosks of HKP Island

3.6.1.10 Emission from idling vehicles at kiosks of HKP Island would also cause cumulative air quality impact on nearby ASRs. The locations of idling vehicles are shown in Appendix 3.7.

Emission from Public Transport Interchanges / Bus Termini

3.6.1.11 2 existing PTIs / bus termini and 1 planned PTIs / bus termini have been identified within the assessment area of 500m from the boundary of the proposed marine facilities and the relevant locations are presented in Appendix 3.7. They include:

· Airport (Ground Transportation Centre) Bus Terminus;

· HZMB Hong Kong Port PTI; and

· the Planned PTI at SKYCITY Site A3.

3.6.1.12 With reference to the latest Chek Lap Kok OZP, planned automated car parks at HKP Island will be located to the east of the Passenger Clearance Building. The proposed automated car parks are proposed on the HKP Island to serve single-plate licensed private cars from Mainland and Macao, and to allow Mainland and Macao drivers to drive through the Hong Kong-Zhuhai-Macao Bridge (HZMB) and park their single-plate vehicles on the HKP Island. Automated parking system (APS), which will be operated by electricity, will be provided at these car parks. Under this system, vehicles will be transported by the system to designated spot during the whole parking and retrieving process. Engine will be turned off once the drivers enter the transfer cabin of the system.

3.6.1.13 As the proposed automated car parks only to serve private cars, the start emission induced by the private cars using the automated car parks, would be included along local and rural roads with post speed of 50km/hr and the roads connecting to the parking sites.

3.6.1.14 In addition, AsiaWorld-Expo Bus Terminus will be decommissioned before the construction of the Project. Therefore, emission from AsiaWorld-Expo Bus Terminus is excluded in the quantitative assessment.

Emission from Existing Marine Vessels

3.6.1.15 There are emissions from the existing passenger vessels at SkyPier, which provides ferry services for transit passengers from HKIA to nine ports in the Greater Bay Area and Macau. For the ferry activities of SkyPier, the schedule has been obtained from AAHK. In view of the development of COVID-19 epidemic situation, the ferry services between Skypier and Macau / Skypier and were suspended since 2020. The typical operational modes of the vessels were made reference to the MVEIS.

3.6.1.16 Potential air quality impacts arising from the marine vessels would cause cumulative air quality impact and the locations of relevant marine routes are shown in Appendix 3.8.

Emission from Other Far-field Emission Sources

3.6.1.17 Other far-field emission sources outside the assessment area which would also have certain influence on the background air quality level include territory wide public electricity generation, civil aviation, road transport, navigation, industries, other fuel combustion and non-combustion sources as well as regional emission from the PRD. These sources are included in far-field modelling (i.e. the PATH model).

3.6.1.18 In order to account for the spatial variations in background concentration, major point sources within 4km from the identified ASRs have been reviewed. No major point source is identified within 4km from the identified ASRs.

Key Pollutants of Concern

3.6.1.19 NO₂, RSP, FSP and SO₂ are considered as the key air pollutants for quantitative air quality assessment for the operation phase of the proposed marine facilities.

3.6.1.20 Nitrogen Oxides (NO_x) are usually produced in combustion processes. Emissions from navigation, public electricity generation and road transport sectors are the major sources of NO_x in Hong Kong. NO₂ is mainly formed from the oxidation of NO_x emitted from fuel combustion. According to the 2020 Hong Kong Emission Inventory Report published by EPD, navigation was the largest NO_x emission source and accounted for 36% of total NO_x emissions in 2020. Therefore, induced marine traffic would increase the NO_x emission and subsequent NO₂ concentration near the proposed marine facilities. As such, NO₂ is one of the key air pollutants for quantitative air quality assessment for the operation phase of the proposed marine facilities.

3.6.1.21 Respirable Suspended Particulates (RSP) refers to suspended particulates with a nominal aerodynamic diameter of 10µm or less. Navigation, non-combustion and other combustion sectors are the major local sources of ambient RSP. According to the 2020 Hong Kong Emission Inventory Report published by EPD, navigation sector was the largest RSP emission source and accounted for 29% of the total RSP emission in Year 2020.

3.6.1.22 Fine Suspended Particulates (FSP) refers to suspended particulates with a nominal aerodynamic diameter of 2.5µm or less. FSP has the same emission sources as RSP, which is also mainly contributed by regional sources. According to the 2020 Hong Kong Emission Inventory Report published by EPD, navigation sector was the largest FSP emission source and accounted for 35% of the total emission in Year 2020.

3.6.1.23 Both RSP and FSP emissions would be increased by the induced marine traffic, which results in increased concentrations near the proposed marine facilities. Hence, RSP and FSP are also the key air pollutants for quantitative air quality assessment for the operational phase of the proposed marine facilities.

3.6.1.24 Sulphur dioxide (SO₂) is formed primarily from the combustion of sulphur-containing fossil fuels. According to the 2020 Hong Kong Emission Inventory Report published by EPD, public electricity generation and navigation sectors were the major sources of SO₂, accounting for 52% and 39% of total SO₂ emissions in 2020, respectively. SO₂ is therefore one of the key air pollutants for quantitative air quality assessment for the operation phase of the proposed marine facilities.

3.6.1.25 According to the latest statistics of 2020 Hong Kong Emission Inventory Report, the SO₂ of vehicle emissions stayed at a very low level in the past few years because of the introduction of Euro V diesel in December 2007, which has the sulphur content capped at 0.001%. 39% of total SO₂ emission in Hong Kong is attributed to navigation while 1% of the total SO₂ emission is due to road transport. The introduction of ultra-low sulphur diesel for vehicle fleet in 2000 has also helped to reduce the SO₂ emission from road transport in Hong Kong. The potential for cumulative impacts from the road transportation in terms of SO₂ is, therefore, considered to be minimal.

3.6.1.26 Carbon monoxide (CO) is the pollutant emitted from the incomplete combustion of the fossil fuel of the vehicles. According to the Air Quality in Hong Kong 2021 published by EPD, the highest 1-hour average (2,150mg/m³) and 8-hour average (1,774mg/m³) recorded at EPD’s monitoring stations are well below the respective AQO limits. Therefore, it is concluded that the CO would not be a critical air pollutant and has not been assessed in this assessment.

3.6.1.27 Formation of Ozone (O₃) results from a set of complex chain reactions between various chemical species including NOx and VOC, under favourable meteorological conditions. Therefore, the formation of O₃ is affected by the concentrations of NOx and VOC, atmospheric oxidation, temperature, radiation, etc in the atmosphere. Overall higher O₃ levels would not occur at the urban area or industrial areas because of the presence of high levels of NOx such that the O₃ reacts with NO to give NO₂ and, thus, results in O₃ removal. Therefore, O₃ is not considered as a key air pollutant during the operation of the Project.

3.6.1.28 Lead (Pb) is the only criteria pollutant included in the AQOs that is also a TAP. Leaded petrol has been banned in Hong Kong since April 1999. According to the Air Quality in Hong Kong 2021 published by EPD, the recorded annual averages of Pb, ranging from 9ng/m³ to 11ng/m³, were well below the respective annual AQO limit of 500ng/m³. Therefore, lead is not considered as a key pollutant for the air quality assessment in this assessment.

3.6.2 Assessment Methodology

3.6.2.1 Quantitative air quality impact assessment will be conducted to evaluate the air quality impact arising from three classes of emission sources depending on their distance from the Project, including:

· Tier 1: Project induced contribution;

· Tier 2: Pollutant-emitting activities in the immediate neighbourhood; and

· Tier 3: Other contributions from pollution not accounted for by Tiers 1 and 2.

3.6.2.2 As mentioned in Section 3.5.2.2 and Section 3.5.2.3, Tiers 1 and 2 emissions are modelled using near-field dispersion models (i.e. AERMOD and CALINE4), while the effect from Tier 3 emissions are simulated using far-field dispersion model (i.e. the PATH model).

3.6.2.3 The predicted cumulative daily and annual average concentrations of RSP and FSP, 1-hour and annual average concentrations of NO₂ and 10-minute and 24-hour average concentration of SO₂ are calculated based on the modelling results from Tiers 1, 2 and 3. The predicted pollutant concentration levels at ASRs are compared with the relevant AQOs to determine the compliance.

Determination of the Assessment Year

3.6.2.4 According to Appendix B, Clause 5 (iv) of the EIA Study Brief for the Project, the air pollution impacts of future road traffic shall be calculated based on the highest emission strength from the road vehicles in the assessment area within the next 15 years upon commencement of operation of the Project. The maximum number of berths will be considered in the assessment. The daily movements of marine vessels associated with the proposed marine facilities is assumed to be steady within the next 15 years. The projected future peak marine traffic activity of pleasure vessels to/from the proposed berthing facilities is anticipated to be 44 vessel trips per day, while the projected marine traffic activity of the vessels to/from the proposed pier 30 vessel trips per day. Both marine traffic activity from the proposed berth facilities and proposed pier are considered.

3.6.2.5 Based on the tentative implementation programme, the Project, including ATCL and marine facilities, will be commenced by Year 2028. Sensitivity tests were carried out for Year 2028 (first commissioning), Year 2035 (interim year) and Year 2043 (15 years after first commissioning) to determine the highest emission scenario and the worst assessment year.

3.6.2.6 The traffic forecast data in Years 2028, 2035 and 2043 were provided by the Project Traffic Consultant, which was submitted to the TD. TD has no comments from a traffic engineering point of view on traffic data. Traffic forecast has been presented in Appendix 3.3. The vehicular emission factor for Years 2028, 2035 and 2043 was extracted from EMFAC-HK v4.3 in EMFAC mode with the representative data for temperature and relative humidity recorded at Chek Lap Kok Weather Station in Year 2021 obtained from Hong Kong Observatory (HKO). The detailed calculation of vehicular emission is presented in Appendix 3.4. According to the result presented in Appendix 3.4, Year 2028 has been selected as representing the worst-case year for the operational air quality impact assessment. As such, all modelling has used the emission factors from Year 2028 to determine the impacts on sensitive receivers.

Vehicular Emissions from Open Roads

3.6.2.7 Assessment methodology and modelling approach was the same as that for vehicular emissions from open roads during the construction of the Project, which was discussed in Section 3.5.2.28 to Section 3.5.2.31.

Emission from Idling Vehicles at Kiosk of HKP Island

3.6.2.8 Assessment methodology and modelling approach was the same as that for emission from Idling Vehicles at Kiosk of HKP Island during the construction of the Project, which was discussed in Section 3.5.2.36.

Emission from Public Transport Interchanges / Bus Termini

3.6.2.9 Assessment methodology and modelling approach was the same as that for emission from Public Transport Interchanges / Bus Termini during the construction of the Project, which was discussed in Section 3.5.2.37 to Section 3.5.2.40.

Emission from Marine Vessels

3.6.2.10 Assessment methodology and modelling approach was the same as that for emission from marine vessels during the construction of the Project, which was discussed in Section 3.5.2.41 to Section 3.5.2.43.

Ozone Limiting Method for Short-term Cumulative NO₂ Assessment

3.6.2.11 Ozone Limiting Method (OLM) was adopted for conversion of NO from sources associated with vehicular emission and NOx from marine emission to NO₂ based on the background O₃ levels from PATH v2.1. The initial NO₂/NO_x ratio from marine emission is assumed to be 10%.

3.6.2.12 NO_2(predicted) = NO_2(vehicular) + 0.1 x NO_x(marine) + Min[NO_(vehicular) + 0.9 x NO_x(Marine) or (46/48) x O_3(PATH)]

Where

NO_2(predicted) = the predicted NO₂ concentration

NO_2(vehicular) = the sum of predicted initial NO₂ concentration from sources associated with vehicular emission

NO_(vehicular) = the sum of predicted initial NO concentration from sources associated with vehicular emission

NO_x(marine) = the sum of predicted initial NOx concentration from marine emission

O_3(PATH) = the background O₃ concentration from PATH v2.1

Jenkin Method for Long-term Cumulative NO₂ Assessment

3.6.2.13 Jenkin Method was adopted for the conversion of cumulative NO_x to NO₂ with reference to the “Review of Methods for NO to NO₂ Conversion in Plumes at Short Ranges” published by Environment Agency, UK. The use of project specific empirical relationship and the calculation details has been presented in Appendix 3.10.

Background Contribution

3.6.2.14 The approach of the background contribution has been discussed in Section 3.5.2.44. The background RSP, FSP, NO₂ and SO₂ concentration levels for Year 2025 of Grid (17, 33) are extracted from the PATH model and adopted in operational air quality impact assessment.

3.6.3 Cumulative Results

3.6.3.1 The cumulative impacts including the vehicular emissions, marine emissions and background pollutant concentration at the ASRs during the operational phase are summarised in Table 3.10 and Table 3.11 and presented in Appendix 3.11.

Table 3.10 Predicted Cumulative Concentrations of RSP and FSP at the Most Affected Assessment Levels of ASRs

ASR ID	Pollutant Concentration (µg/m^3)
	RSP		FSP
	10^th Highest Daily Average	Annual Average	36^th Highest Daily Average	Annual Average
AQO	100	50	50	25
A01	68	29	25	16
A02	68	29	25	16
A03	68	29	26	16
A04	68	29	26	16
A05	68	29	26	16
A06	68	29	26	16
P02	68	29	26	16
P03	68	29	26	16
P04	68	29	26	16

Table 3.11 Predicted Cumulative Concentrations of NO₂ and SO₂ at the Most Affected Assessment Levels of ASRs

ASR ID	Pollutant Concentration (µg/m^3)
	NO2		SO2
	19^th Highest Daily Average	Annual Average	The Highest 10-min Average	4^th Highest Daily Average
AQO	200	40	500	50
A01	145	34	101	16
A02	137	31	100	15
A03	143	35	100	15
A04	151	36	100	15
A05	142	37	100	15
A06	143	34	100	17
P02	145	35	100	17
P03	149	39	100	15
P04	154	36	100	16

3.6.3.2 Based on the above results, the predicted pollutant concentrations at the representative ASRs are complying with the relevant AQOs. Hence, no adverse air quality impact from the Project is anticipated.

3.6.3.3 Contour plots of 10^th highest daily average RSP at 15.0mAG, annual average RSP at 1.5mAG, 36^th highest daily and annual average FSP, 19^th highest hourly and annual average NO₂ at 1.5mAG_, the highest 10-min average SO₂ at 1.5mAG and 4^th highest daily average SO₂ at 15.0mAG during the operational phase are presented in Figure 3.9, Figure 3.10, Figure 3.11, Figure 3.12, Figure 3.13, Figure 3.14, Figure 3.15 and Figure 3.16, respectively. Additional contour plots of 19^th highest hourly average NO₂ at 5mAG, annual average NO₂ at 5mAG and 10mAG are presented in Figure 3.17, Figure 3.18 and Figure 3.19, respectively. With reference to the contour plots of 10th highest daily and annual average RSP, 36th highest daily and annual average FSP, and the highest 10-min and 4th highest daily average SO₂, there is no exceedance zone identified. Exceedance zones are found in the contour plots of 19^th highest hourly NO₂ at 1.5mAG, and annual average NO₂ at 1.5mAG and 5.0mAG. However, no existing and future air sensitive uses including openable window / fresh air intakes of the ventilation system or recreational uses in open space are situated within the exceedance zones of 19^th highest hourly average NO₂ according to the information provided by AAHK. Although 11 SKIES (P03), planned commercial use (P04), planned Hong Kong Airport Terminal 2 and temporary site offices are found within the exceedance zones of annual average NO₂, as confirmed by AAHK, no air sensitive uses including openable window / fresh air intakes of the ventilation system for 11 SKIES (P03), planned commercial use (P04), planned Hong Kong Airport Terminal 2 or recreational uses in open space will be placed within the exceedance zones. As for temporary site offices located to the north of Sky City Interchange and west of the proposed marine facilities, they would be decommissioned at the end of 2023 and 2026, respectively, before the operational year of the Project, and no air sensitive uses would be sited there afterward according to the information provided by AAHK.

3.6.4 Evaluation of Residual Impact

3.6.4.1 No adverse residual impact would be expected during the operational phase of the Project.

3.7 Environmental Monitoring and Audit

3.7.1.1 The assessment has concluded that mitigated construction dust impacts are within the acceptable levels and no adverse impacts will occur. However, it is recommended that, given the close proximity of the ASRs to the works area, that construction phase environmental monitoring and audit is undertaken to ensure that there are no adverse impacts during the implementation of the construction activities and ensure that recommended mitigation measures are implemented. EM&A during the operational phase is not required. Further details of the specific EM&A requirements are detailed in the EM&A Manual.

3.8 Conclusions

3.8.1.1 Potential air quality impacts from the construction works for the Project would mainly be related to construction dust from excavation, materials handling, spoil removal and wind erosion. Cumulative dust impact including the vehicular emission and marine emissions have been included in construction phase. With the implementation of regular watering of all exposed areas and mitigation measures as defined in the Air Pollution Control (Construction Dust) Regulation, all identified representative sensitive receivers would comply with the relevant AQOs and the criterion stipulated in EIAO-TM.

3.8.1.2 In respect of the operational phase of the Project, the assessment revealed that the predicted cumulative air quality impacts comply with the RSP, FSP, NO2 and SO2 AQOs at all the identified representative ASRs and no adverse operational phase impacts are expected to occur.