TABLE OF CONTENTs

 

3              Air Quality Impact  3-1

3.1          Introduction. 3-1

3.2          Environmental Legislation, Policies, Plans, Standards and Criteria. 3-1

3.3          Baseline Conditions and Future Trends. 3-2

3.4          Identification of Air Sensitive Receivers. 3-3

3.5          Identification of Environmental Impacts. 3-4

3.6          Prediction and Evaluation of Environmental Impact 3-5

3.7          Mitigation of Environmental Impact 3-6

3.8          Evaluation of Residual Environmental Impacts. 3-6

3.9          Environmental Monitoring and Audit 3-6

3.10        Conclusion. 3-6

 

 

TABLES

Table 3.1          Hong Kong Air Quality Objectives

Table 3.2          Average Concentrations of Pollutant in the Recent Five Years (Year 2013 - 2017)

                        at Tung Chung EPD Air Quality Monitoring Station

Table 3.3          Relevant Air Pollutant Concentrations extracted from PATH-2016 Model

Table 3.4          Identified Air Sensitive Receivers

 

FIGURES

Figure 3.1         Assessment Area and Location of Identified ASRs

 

           


3                       Air Quality Impact

3.1                    Introduction

3.1.1                This section presents the assessment on potential air quality impacts arising from construction and operation of the Project, which has been conducted in accordance with the criteria and guidelines as stated in Section 1 of Annex 4 and Annex 12 of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM) as well as the requirements given in Clause 3.4.3 and Appendix B of the EIA Study Brief (No. ESB-302/2017).

3.1.2                The potential dust impact arising from construction activities of the Project has been assessed and appropriate mitigation measures are proposed to alleviate any identified potential air quality impact.

3.1.3                During operational phase of the Project, only electric vehicles will be used to provide the hassle-free bonded cross-boundary bus trips, and potentially bonded limousine (electrical vehicles) trips, subject to regulatory approval from HKSAR Security Bureau and law enforcement agencies, between the Intermodal Transfer Terminal (ITT) and Zhuhai/Macao BCF via the Bonded Vehicular Bridge and Associated Roads connecting to the HKBCF.  As such, there will be no air pollutants emission during the operation of the Project.

3.2                    Environmental Legislation, Policies, Plans, Standards and Criteria

3.2.1                The criteria and guidelines for air quality assessment are laid down in Section 1 of Annex 4 and Annex 12 of the EIAO-TM.

3.2.2                The Air Pollution Control Ordinance (APCO) provides the statutory authority for controlling air pollutants from a variety of sources.  The Hong Kong Air Quality Objectives (AQOs), which stipulate the maximum allowable concentrations over specific periods for typical pollutants, should be met.  The relevant AQOs are listed in Table 3.1.

Table 3.1   Hong Kong Air Quality Objectives

Pollutant

Averaging Time

Maximum Average Concentration (µg/m3) (1)

No. of Exceedances Allowed (2)

Fine Suspended Particulates

(PM2.5 / FSP) (4)

24-hr

75

9

Annual (3)

35

NA

Respirable Suspended Particulates (PM10 / RSP) (5)

24-hr

100

9

Annual (3)

50

NA

Sulphur Dioxide (SO2)

10-min

500

3

24-hr

125

3

Nitrogen Dioxide (NO2)

1-hr

200

18

Annual (3)

40

NA

Carbon Monoxide (CO)

1-hr

30,000

0

8-hr

10,000

0

Photochemical Oxidants (as ozone)

8-hr

160

9

Lead (Pb)

Annual (3)

0.5

NA

Notes:

(1)Measured at 293 K and 101.325 kPa.

(2)The number of exceedances allowed per year.

(3)Arithmetic mean.

(4)Suspended particulates in air with a nominal aerodynamic diameter of 2.5 mm or smaller.

(5)Suspended particulates in air with a nominal aerodynamic diameter of 10 mm or smaller.

3.2.3                The Annex 4 of EIAO-TM stipulates that the hourly Total Suspended Particulate (TSP) concentration should not exceed 500 µg/m3 (measured at 25°C and one atmosphere) for construction dust impact.

Air Pollution Control (Construction Dust) Regulation

3.2.4                Notifiable and regulatory works are under the control of Air Pollution Control (Construction Dust) Regulation.  Notifiable works include site formation, reclamation, demolition, foundation and superstructure construction for buildings and road construction.  Regulatory works include building renovation, road opening and resurfacing, slope stabilisation, and other activities including stockpiling, dusty material handling, excavation, concrete production, etc.  This Project is expected to include notifiable works (site clearance and superstructure works) and regulatory works (dusty material handling and minor excavation).  Contractors and site agents are required to inform EPD and adopt dust reduction measures to minimise dust emissions, while carrying out construction works, to the acceptable level.

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

3.2.5                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.

3.3                    Description of the Environment and Future Trends

3.3.1                The Project site is situated between the HKBCF Island and the HKIA, at the south of the existing SkyPier.  The location of the Project is shown in Figure 3.1.  The potential air pollutants sources in the study area would be traffic emissions from existing road networks at HKIA and planned roads at HKBCF and Hong Kong Link Road (HKLR), marine emissions from nearby marine traffic, and emission from HKIA. 

3.3.2                The nearest EPD fixed air quality monitoring station is located at Tung Chung Health Centre.  The annual average monitoring data recorded at EPD’s Tung Chung air quality monitoring station has shown steady trend of pollutants’ concentration in the past five years.  The recent five years (2013 - 2017) annual average concentrations of the relevant air pollutants (i.e. PM10 and PM2.5) during construction phase are summarised in Table 3.2.

Table 3.2    Average Concentrations of Pollutant in the Recent Five Years (Year 2013 – 2017) at Tung Chung EPD Air Quality Monitoring Station

Pollutant

2017

2016

2015

2014

2013

Mean

10th Highest Daily Average PM10 Concentration (µg/m3)

81

92

93

101

108

95.0

Annual Average PM10 Concentration (µg/m3)

34

33

36

39

42

36.8

10th Highest Daily Average PM2.5 Concentration (µg/m3)

57

63

65

65

76

65.2

Annual Average PM2.5 Concentration (µg/m3)

21

21

22

24

26

22.8

 

3.3.3                Based on the monitoring data, there was a decreasing trend for the PM10 and PM2.5 pollutants concentrations in 10th highest daily average concentration and annual average concentrations.  With the exception of PM10 at 10th highest daily average concentration at Year 2013 to 2014, and PM2.5 at 10th highest daily average concentration at Year 2013, the pollutant concentrations at other times would fulfil the current AQOs.

3.3.4                The future year background concentrations are made reference to the EPD’s PATH modelling results.  The PATH model is a regional air quality model developed by EPD to simulate air quality over Hong Kong against the Pearl River Delta (PRD) as background.  Since the tentative commencement year of the construction work for the Project would be in Year 2020, the PATH Model results for future year would be made reference to Year 2020.  The particulates concentrations of the study area extracted from Year 2020 PATH results are presented in Table 3.3.

Table 3.3      Relevant Air Pollutant Concentrations extracted from PATH-2016 Model

Pollutant

Averaging Time

AQO [1]

PATH Grid Cell [2] [3]

Year 2020

(17, 33)

(18, 33)

(19, 33)

Fine Suspended Particulates (PM2.5) [4][5]

10th highest 24-hr

75 (9)

60

60

61

Annual

35

24

24

24

Respirable Suspended Particulates  (PM10) [5]

10th highest 24-hr

100 (9)

80

81

81

Annual

50

34

34

34

Notes:

[1] Values in ( ) mean the number of exceedances allowed per year.

[2] Bolded values mean exceedance of the AQOs.

[3] N/A – Not Available.

[4] Since PM2.5 is not available from PATH model outputs, 24-hour average PM2.5 and annual average PM2.5 are estimated by 0.75 x PM10 and 0.71 x PM10 respectively with reference to Guidelines on the Estimation of PM2.5 for Air Quality Assessment in Hong Kong.

[5] 10th highest daily and annual RSP concentration is adjusted by adding 26.5 µg/m3 and 15.6 µg/m3 respectively with reference to Guidelines on Choice of Models and Model Parameters.  Same adjustment is applied to estimation of PM2.5 as well.

 

 

3.4                    Identification of Air Sensitive Receivers

3.4.1                In accordance with Annex 12 of the EIAO-TM, any domestic premises, hotel, hostel, hospital, clinic, nursery, temporary housing accommodation, school, educational institution, office, factory, shop, shopping centre, place of public worship, library, court of law, sports stadium or performing arts centre are considered as air sensitive receivers (ASRs).  Any other premises or place with which, in terms of duration or number of people affected, has a similar sensitivity to the air pollutants as the aforelisted premises and places is also considered to be a sensitive receiver. 

3.4.2                In accordance with Clause 3.4.3.2 of the EIA Study Brief, the assessment area for air quality impact assessment should be defined by a distance of 500 m from the boundary of the Project site.  Illustration of the proposed assessment area is presented in Figure 3.1.

3.4.3                For identification of the representative ASRs within the assessment area that would likely be affected by the Project, a review has been conducted based on relevant available information including topographic maps, Outline Zoning Plans (OZPs) (e.g. Chek Lap Kok – OZP (Plan No. S/I-CLK/14) and Tung Chung Extension Area – OZP (Plan No. S/I-TCE/2)) and other published plans in the vicinity of the Project site.  For the Northern Commercial District (NCD) located at the western side of the assessment area, as the target completion date of NCD is Year 2022 in which the construction works of the Project would be completed, it is not selected as an ASR. 

3.4.4                The representative existing and planned ASRs identified within assessment area are presented in Table 3.4.  Locations of these ASRs are shown in Figure 3.1

Table 3.4    Identified Air Sensitive Receivers

ID

Description

Land Use

Approx. Distance between ASR and Project Boundary

Remarks

1

SkyPier

Other Specific Use

10 m

Existing

2

SkyCity Marriott Hotel

Commercial

150 m

Existing

3

Planned Passenger Clearance Building of HKBCF(1)

Other Specific Use

100 m

Planned

4

East Sea Rescue Berth Airport Fire Contingent

Other Specific Use

370 m

Existing

5

AsiaWorld-Expo

Commercial

320 m

Existing

6

Hotel at North Commercial District Site A1a

Commercial

230 m

Planned

7

Intermodal Transfer Terminal

Other Specific Use

0 m

Planned

Note: (1) as confirmed with Highways Department, the Passenger Clearance Building would be in operation before the construction of the Project, i.e. before Year 2020.

 

3.4.5                The representative ASRs as presented in Table 3.4 may be affected by potential dust impact arising from construction activities during construction phase of the Project.  During operation of the Project, only electric vehicles would be adopted for the hassle-free bonded vehicle services between ITT and HKBCF through the Bonded Vehicular Bridge and associated roads, no air pollutants emissions would be generated.  Therefore, no ASR is identified to be affected by operation of the Project.

3.5                    Identification of Environmental Impacts

Construction Phase

3.5.1                During the construction phase, land based construction activities of the Project would generate fugitive dust with potential impacts on neighboring ASRs from various construction activities, including site clearance, minor excavation with limited backfilling, and wind erosion of exposed area.  Since bridge deck section or segments will be prefabricated in a fabrication yard off-site, and delivered to the site and installed by use of lifting method or float-in method using barges for marine sections, and lifting by mobile or crawler crane for land sections.  Potential dust impact from these other construction activities is not considered to be significant and no associated adverse dust impact is anticipated.

3.5.2                In addition, the abovementioned construction works will be of small-scale and confined within small work area, work area with dusty activities would be less than 100 m2 as confirmed by Project Engineer, and that construction activities will not take place at the entire construction work site at the same time, but to be undertaken at multiple work fronts at different construction periods.  The construction activities at different work fronts will not take place concurrently.

3.5.3                As the majority of construction works for the Project are marine based, and bridge deck sections for land sections will be prefabricated in a fabrication yard off-site and delivered to the site for installation by mobile or crawler crane, limited amount of powered mechanical equipment (PME) are required on site for land based construction works.  Moreover, according to the Air Pollution Control (Non-road Mobile Machinery) (Emission) Regulation, starting from 1 December 2015, only approved or exempted non-road mobile machinery are allowed to be used in construction sites, these approved or exempted non-road mobile machinery have emission limit values of air pollutants including particulate pollutants.  Hence, no significant dust emission from the operation of PMEs and non-road mobile machinery is anticipated.

3.5.4                Considering the small-scale and nature of the construction activities for the Project, and that construction activities at different work locations will not take place concurrently, there will be no significant dust emission from the works area to the surrounding ASRs and adverse construction dust impact to surrounding ASRs is not anticipated.  Therefore, quantitative construction dust assessment is considered unnecessary.

3.5.5                Fuel combustion from the use of PME during construction works could be a source of NO2, SO2 and CO.  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.  Hence, with the implementation of the said Regulation, the emissions from PMEs are considered relatively small and will not cause adverse air quality impact to the surrounding ASRs.

Operation Phase

3.5.6                The Project is a Bonded Vehicular Bridge situated between HKBCF Island and HKIA, and consist of associated road networks at HKBCF, with purpose to serve ATB and BTA passengers.  As confirmed by AAHK, only electric vehicles will be used on the Bonded Vehicular Bridge and Associated Roads under normal circumstances.  The hassle-free bonded cross-boundary bus trips and potentially bonded limousine trips which are subject to regulatory approval from HKSAR Security Bureau and law enforcement agencies, between the ITT and Zhuhai/Macao BCF via the Bonded Vehicular Bridge and Associated Roads connecting to the HKBCF, are electric vehicles.  As such, there will be no air pollutants emission during the operation of the Project. 

3.6                    Prediction and Evaluation of Environmental Impact

Construction Phase

3.6.1                As mentioned in Sections 3.5.1 to 3.5.4, the Project will not generate significant dust emission during the construction works due to small scale and nature of the construction works, and construction activities will not be conducted concurrently at different work locations.  Hence, there will no significant dust emission from the works area to the surrounding ASRs and adverse construction dust impact to surrounding ASRs is not anticipated.  Nevertheless, dust suppression measures are recommended in Section 3.7.1 to minimise the potential dust emission from the construction of the Project.  

3.6.2                As mentioned in Section 3.5.5, the emissions from PMEs are considered relatively small.  Hence, adverse air quality impact to the surrounding ASRs is not anticipated.  The construction period of the Project potentially overlap with nearby concurrent projects as identified in Table 2.5.  However, work sites of Tung Chung New Town Extension and its Associated Infrastructures and 3RS projects are located more than 500 m, no cumulative dust impact would be anticipated.  The construction works for ITT project and North Commercial District project have been commenced since 2017 and 2018 respectively.  The dusty construction activities such as excavation works and foundation works of these two projects would be likely to be completed by early Year 2020 and therefore would unlikely overlap with the dusty construction activities of the Project.  In addition, the land based works of the Project would only be undertaken on BCF Island only and the scale of the dusty construction works would be small.  With further incorporation of the mitigation measures as mentioned in Section 3.7.1 during the construction phase of this Project, cumulative construction dust impacts would not be expected.

Operation Phase

3.6.3                As mentioned in Section 3.5.6, there will be no air pollutants emission during the operation of the Project.  Hence, adverse air quality impact is not anticipated.

3.7                    Mitigation of Environmental Impact

Construction Phase

3.7.1                Although no adverse dust impact is anticipated from the Project to the surrounding ASRs, dust suppression measures in the Air Pollution Control (Construction Dust) Regulation should be incorporated to control dust emission from the site.  Major control measures relevant to this Project are listed below, and they are recommended to be included in relevant contract documents:

·      Skip hoist for material transport should be totally enclosed by impervious sheeting.

·      All dusty materials should be sprayed with water prior to any loading, unloading or transfer operation so as to maintain the dusty materials wet.

·      All stockpiles of aggregate or spoil should be covered and/or water applied.

·      The height from which excavated materials are dropped should be controlled to a minimum practical height to limit fugitive dust generation from unloading.

·      Every vehicle should be washed to remove any dusty materials from its body and wheels before leaving the construction sites.

·      The load of dusty materials carried by a vehicle leaving a construction site should be covered entirely by clean impervious sheeting to ensure dust materials do not leak from the vehicle

3.7.2                With the implementation of the dust suppression measures, unacceptable construction dust impact would not be anticipated.

Operation Phase

3.7.3                As there will be no air pollutants emission during the operation of the Project, adverse air quality impact is not anticipated.  Therefore, no mitigation measure will be required during the operation phase.

3.8                    Evaluation of Residual Environmental Impacts

3.8.1                No adverse residual air quality impact is anticipated during the construction and operation phases of the Project.

3.9                    Environmental Monitoring and Audit

Construction Phase

3.9.1                No adverse dust impact would be expected during construction phase with the implementation of the recommended mitigated measures and, therefore, monitoring is considered unnecessary.  It is recommended environmental site audit be conducted during the construction phase of the Project in order to ensure that the dust control measures are implemented effectively.

Operation Phase

3.9.2                Since there will be no air pollutants emission during operation phase, no environmental monitoring and audit programme is required.

3.10                  Conclusion

3.10.1              Potential dust impact generated from construction activities, such as site clearance, minor excavation with limited backfilling, wind erosion of exposed area, and emission from PMEs would not be significant.  With implementation of suitable practice and mitigation measures, potential impacts on nearby ASRs in the vicinity of the Project would not be significant and would be controlled to within relevant standards.

3.10.2              The Project is a Bonded Vehicular Bridge situated between HKBCF Island and HKIA, and consist of associated road networks at HKBCF.  As there will be no air pollutants emission during the operation of the Project, adverse air quality impact is not anticipated.  Therefore, no mitigation measure will be required during the operation phase.