Contract No. HY/2011/03

Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road

Section between Scenic Hill and Hong Kong Boundary Crossing Facilities

 

 

 

 

 

 

Quarterly EM&A Report No. 16 (June to August 2016)

 

29 December 2016

 

Revision 1

 

 

 

 

 

 

 

 

 

 

 

 

 

Main Contractor                                                                                                                     Designer

 

 


 


Contents

Executive Summary

1...... Introduction.. 1

1.1                    Basic Project Information. 1

1.2                    Project Organisation. 1

1.3                    Construction Programme. 1

1.4                    Construction Works Undertaken During the Reporting Period. 1

2....... EM&A Requirement 3

2.1                    Summary of EM&A Requirements. 3

2.2                    Action and Limit Levels. 4

2.3                    Event Action Plans. 6

2.4                    Mitigation Measures. 6

3....... Environmental Monitoring and Audit 6

3.1                    Implementation of Environmental Measures. 6

3.2                    Air Quality Monitoring Results. 6

3.3                    Noise Monitoring Results. 7

3.4                    Water Quality Monitoring Results. 7

3.5                    Dolphin Monitoring Results. 8

3.6                    Mudflat Monitoring Results. 18

3.7                    Solid and Liquid Waste Management Status. 29

3.8                    Environmental Licenses and Permits. 29

4....... Environmental Complaint and Non-compliance. 30

4.1                    Environmental Exceedances. 30

4.2                    Summary of Environmental Complaint, Notification of Summons and Successful Prosecution. 31

5....... Comments, Recommendations and Conclusion.. 32

5.1                    Comments. 32

5.2                    Recommendations. 33

5.3                    Conclusions. 33

 

 

 

 

 

 

 

 

 

Figures

 

Figure 1.1         Location of the Site

Figure 2.1         Environmental Monitoring Stations     

Figure 2.2         Transect Line Layout in Northwest and Northeast Lantau Survey Areas

 

                           

Appendices

 

Appendix A       Environmental Management Structure

Appendix B       Construction Programme

Appendix C       Location of Works Areas

Appendix D       Event and Action Plan  

Appendix E       Implementation Schedule of Environmental Mitigation Measures

Appendix F       Site Audit Findings and Corrective Actions

Appendix G      Air Quality Monitoring Data and Graphical Plots

Appendix H       Noise Monitoring Data and Graphical Plots

Appendix I         Water Quality Monitoring Data and Graphical Plots

Appendix J        Dolphin Monitoring Results

Appendix K       Waste Flow Table

Appendix L       Summary of Environmental Licenses and Permits

Appendix M      Record of ˇ§Notification of Environmental Quality Limit Exceedancesˇ¨ and Record of ˇ§Notification of Summons and Prosecutionsˇ¨

Appendix N       Cumulative Statistics on Complaints

Appendix O      Mudflat Monitoring Results


Executive Summary

The Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong Kong Link Road (HKLR) serves to connect the HZMB Main Bridge at the Hong Kong Special Administrative Region (HKSAR) Boundary and the HZMB Hong Kong Boundary Crossing Facilities (HKBCF) located at the north eastern waters of the Hong Kong International Airport (HKIA).

The HKLR project has been separated into two contracts.  They are Contract No. HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter referred to as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between HKSAR Boundary and Scenic Hill.

China State Construction Engineering (Hong Kong) Ltd. was awarded by Highways Department as the Contractor to undertake the construction works of Contract No. HY/2011/03. The main works of the Contract include land tunnel at Scenic Hill, tunnel underneath Airport Road and Airport Express Line, reclamation and tunnel to the east coast of the Airport Island, at-grade road connecting to the HKBCF and highway works of the HKBCF within the Airport Island and in the vicinity of the HKLR reclamation.  The Contract is part of the HKLR Project and HKBCF Project, these projects are considered to be ˇ§Designated Projectsˇ¨, under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap 499) and EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for the Project.  The current Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/K for HKBCF were issued on 22 December 2014 and 11 April 2016, respectively. These documents are available through the EIA Ordinance Register. The construction phase of Contract was commenced on 17 October 2012.

BMT Asia Pacific Limited has been appointed by the Contractor to implement the Environmental Monitoring & Audit (EM&A) programme for the Contract in accordance with the Updated EM&A Manual for HKLR (Version 1.0) and will be providing environmental team services to the Contract.

This is the sixteenth Quarterly EM&A report for the Contract which summarizes the monitoring results and audit findings of the EM&A programme during the reporting period from 1 June 2016 to 31 August 2016.

Environmental Monitoring and Audit Progress

The EM&A programme were undertaken in accordance with the Updated EM&A Manual for HKLR (Version 1.0).  A summary of the monitoring activities during this reporting period is presented as below:

Monitoring Activity

Monitoring Date

June 2016

July 2016

August 2016

Air Quality

1-hr TSP

6, 10, 16, 22 and 28

4, 8, 14, 19, 25 and 29

4, 10, 16, 22 and 26

24-hr TSP

AMS5: 3, 8, 14, 20, 24 and 30

AMS6: 7, 8, 14, 20, 24 and 30

AMS5: 6, 14, 18, 22 and 28

AMS6: 13, 18, 22 and 28

3, 9, 15, 19, 25 and 31

Noise

6, 16, 22 and 28

4, 14, 19 and 25

4, 10, 16 and 22

Water Quality

1, 3, 6, 8, 10, 13, 15, 17, 20, 22, 24, 27 and 29

1, 4, 6, 8, 11, 13, 15, 18, 20, 22, 25, 27 and 29

1, 3, 5, 8, 10, 12, 15, 17, 19, 22, 24, 26, 29 and 31

Chinese White Dolphin

1, 6, 13 and 17

5, 12, 18 and 27

5, 9, 17 and 23

Mudflat Monitoring (Ecology)

4, 5, 6, 18 and 19 

--

--

Mudflat Monitoring (Sedimentation rate)

2

--

--

Site Inspection

1, 8, 15, 22 and 28

6, 13, 20, and 29

3, 10, 17, 24 and 30

 

 

Due to malfunction of HVS at station AMS5, the 24-hr TSP monitoring at AMS5 was rescheduled from 3 June 2016 to 7 June 2016.

Due to power interruption and malfunction of HVS at station AMS5, the 24-hr TSP monitoring at AMS5 was rescheduled from 12 July 2016 to 14 July 2016 respectively.

Due to malfunction of HVS at station AMS6, the 24-hr TSP monitoring on 6 July 2016 was cancelled. The HVS was repaired on 13 July 2016. The 24-hr TSP monitoring at AMS6 was rescheduled from 12 July 2016 to 13 July 2016.

Due to clash of schedule, the dolphin monitoring schedule was rescheduled from 20 June 2016 to 17 June 2016.

Due to boat availability, the dolphin monitoring schedule was rescheduled from 11 July 2016 to 5 July 2016, form 25 July to 12 July 2016, from 22 July to 27 July 2016, 8 August 2016 to 9 August 2016 and form 24 August to 23 August 2016.

As the Strong Wind Signal No. 3 was hoisted by Hong Kong Observatory on 1 August 2016 (11:40am), water quality monitoring (WQM) was carried out at stations SR10A and SR10B only for mid-ebb tide. WQM for remaining stations for mid-ebb tide and WQM at all stations for mid-flood tide was cancelled for safety reason.

Breaches of Action and Limit Levels

A summary of environmental exceedances for this reporting period is as follows:

Environmental Monitoring

Parameters

Action Level (AL)

Limit Level (LL)

Air Quality

1-hr TSP

1

0

24-hr TSP

0

0

Noise

Leq (30 min)

0

0

Water Quality

Suspended solids level (SS)

0

0

Turbidity level

0

0

Dissolved oxygen level (DO)

0

0

Dolphin Monitoring

Quarterly Analysis (Jun 2016 to Aug 2016)

0

1

The Environmental Team investigated all exceedances and found that they were not project related.

All investigation reports for exceedances of the Contract have been submitted to ENPO/IEC for comments and/or follow up to identify whether the exceedances occurred related to other HZMB contracts.

Implementation of Mitigation Measures

Site inspections were carried out on a weekly basis to monitor the implementation of proper environmental pollution control and mitigation measures for the Project.  Potential environmental impacts due to the construction activities were monitored and reviewed.

Complaint Log

There was one complaint received in relation to the environmental impacts during the reporting period.

A summary of environmental complaints for this reporting month is as follows:

Environmental Complaint No.

Date of Complaint Received

Description of Environmental Complaints

COM-2016-087

28 June 2016

Water Quality

 

Notifications of Summons and Prosecutions

There were no notifications of summons or prosecutions received during this reporting period.

Reporting Changes

This report has been developed in compliance with the reporting requirements for the quarterly summary EM&A reports as required by the Updated EM&A Manual for HKLR (Version 1.0). 

The proposal for the change of Action Level and Limit Level for suspended solid and turbidity was approved by EPD on 25 March 2013.

The revised Event and Action Plan for dolphin monitoring was approved by EPD on 6 May 2013.

The original monitoring station at IS(Mf)9 (Coordinate- East:813273, North 818850) was observed inside the perimeter silt curtain of Contract HY/2010/02 on 1 July 2013, as such the original impact water quality monitoring location at IS(Mf)9 was temporarily shifted outside the silt curtain.  As advised by the Contractor of HY/2010/02 in August 2013, the perimeter silt curtain was shifted to facilitate safe anchorage zone of construction barges/vessels until end of 2013 subject to construction progress.  Therefore, water quality monitoring station IS(Mf)9 was shifted to 813226E and 818708N since 1 July 2013.  According to the water quality monitoring teamˇ¦s observation on 24 March 2014, the original monitoring location of IS(Mf)9 was no longer enclosed by the perimeter silt curtain of Contract HY/2010/02.  Thus, the impact water quality monitoring works at the original monitoring location of IS(Mf)9 has been resumed since 24 March 2014.

Transect lines 1, 2, 7, 8, 9 and 11 for dolphin monitoring have been revised due to the obstruction of the permanent structures associated with the construction works of HKLR and the southern viaduct of TM-CLKL, as well as provision of adequate buffer distance from the Airport Restricted Areas.  The EPD issued a memo and confirmed that they had no objection on the revised transect lines on 19 August 2015.


1        Introduction

1.1                 Basic Project Information

1.1.1       The Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong Kong Link Road (HKLR) serves to connect the HZMB Main Bridge at the Hong Kong Special Administrative Region (HKSAR) Boundary and the HZMB Hong Kong Boundary Crossing Facilities (HKBCF) located at the north eastern waters of the Hong Kong International Airport (HKIA).

1.1.2       The HKLR project has been separated into two contracts. They are Contract No. HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter referred to as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between HKSAR Boundary and Scenic Hill.

1.1.3       China State Construction Engineering (Hong Kong) Ltd. was awarded by Highways Department (HyD) as the Contractor to undertake the construction works of Contract No. HY/2011/03.  The Contract is part of the HKLR Project and HKBCF Project, these projects are considered to be ˇ§Designated Projectsˇ¨, under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap 499) and EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for the Project.  The current Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/K for HKBCF were issued on 22 December 2014 and 11 April 2016, respectively. These documents are available through the EIA Ordinance Register. The construction phase of Contract was commenced on 17 October 2012.  Figure 1.1 shows the project site boundary.

1.1.4       BMT Asia Pacific Limited has been appointed by the Contractor to implement the EM&A programme for the Contract in accordance with the Updated EM&A Manual for HKLR (Version 1.0) for HKLR and will be providing environmental team services to the Contract.  Ramboll  Environ Hong Kong Ltd. was employed by HyD as the Independent Environmental Checker (IEC) and Environmental Project Office (ENPO) for the Project. The project organization with regard to the environmental works is provided in Appendix A.

1.1.5       This is the sixteenth Quarterly Environmental Monitoring and Audit (EM&A) report for the Contract which summarizes the monitoring results and audit findings of the EM&A programme during the reporting period from 1 June 2016 to 31 August 2016.

1.2                Project Organisation

1.2.1       The project organization structure and lines of communication with respect to the on-site environmental management structure with the key personnel contact names and numbers are shown in Appendix A. 

1.3                Construction Programme

1.3.1       A copy of the Contractorˇ¦s construction programme is provided in Appendix B. 

1.4                Construction Works Undertaken During the Reporting Period

1.4.1       A summary of the construction activities undertaken during this reporting period is shown in Table 1.1.  The Works areas of the Contract are showed in Appendix C.

Table 1.1          Construction Activities during Reporting Period

Description of Activities

Site Area

Dismantling/trimming of temporary 40mm stone platform for construction of seawall

Portion X

Filling works behind stone platform

Portion X

Construction of seawall

Portion X

Loading and unloading of filling materials

Portion X

Pipe piling work

Portion X

Excavation and lateral support works for Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Construction of tunnel box structure at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Backfilling at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Excavation for HKBCF to Airport Tunnel

Portion X

Pipe piling and sheet piling works for Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X and Y

Jet Grouting Works for Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X and Y

Works for diversion

Airport Road

Utilities detection

Airport Road/ Airport Express Line/ East Coast Road

Establishment of Site Access

Airport Road/ Airport Express Line/ East Coast Road

Canopy pipe drilling / Box Jacking underneath Airport Express Line

Airport Express Line

Pipe roofing drilling / Mined Tunnel excavation underneath Airport Road

Airport Road

Lateral support works at shaft 3 extension north shaft & south shaft (Package T1.12.1)

Kwo Lo Wan Road

Excavation and Lateral Support Works for HKBCF to Airport Tunnel West (Cut & Cover Tunnel)

Airport Road

Excavation and Lateral Support Works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel)

Portion X

Utility culvert excavation

Portion Y

Sub-structure & superstructure works for Highway Operation and Maintenance Area Building

Portion Y

Superstructure works for Scenic Hill Tunnel West Portal Ventilation building

West Portal

Excavation for Scenic Hill Tunnel

West Portal

Box Jacking underneath Airport Express Line

Airport Express Line

Mined Tunnel excavation underneath Airport Road

Airport Road

Excavation and Lateral Support Works at shaft 3 extension north shaft & south shaft (Package T1.12.1)

Kwo Lo Wan Road

Mined Tunnel excavation/ Box Jacking underneath  Airport Road and Airport Express Line

Airport Road and Airport Express Line

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2        EM&A Requirement

2.1                Summary of EM&A Requirements

2.1.1       The EM&A programme requires environmental monitoring of air quality, noise, water quality, dolphin monitoring and mudflat monitoring as specified in the approved EM&A Manual.

2.1.2       A summary of Impact EM&A requirements is presented in Table 2.1. The locations of air quality, noise and water quality monitoring stations are shown as in Figure 2.1.  The transect line layout in Northwest and Northeast Lantau Survey Areas is presented in Figure 2.2.

Table 2.1          Summary of Impact EM&A Requirements

Environmental Monitoring

Description

Monitoring Station

Frequencies

Remarks

Air Quality

1-hr TSP

AMS 5 & AMS 6

At least 3 times every 6 days

While the highest dust impact was expected.

24-hr TSP

At least once every 6 days

--

Noise

Leq (30mins),
L10
(30mins) and
L90
(30mins)

NMS5

At least once per week

Daytime on normal weekdays (0700-1900 hrs).

Water Quality

ˇP    Depth

ˇP    Temperature

ˇP    Salinity

ˇP    Dissolved Oxygen (DO)

ˇP    Suspended Solids (SS)

ˇP    DO Saturation

ˇP    Turbidity

ˇP    pH

ˇP    Impact Stations:
IS5, IS(Mf)6, IS7, IS8, IS(Mf)9 & IS10,

ˇP    Control/Far Field Stations:
CS2 & CS(Mf)5,

ˇP    Sensitive Receiver Stations:
SR3, SR4, SR5, SR10A & SR10B

Three times per week during mid-ebb and mid-flood tides (within ˇÓ 1.75 hour of the predicted time)

3

(1 m below water surface, mid-depth and 1 m above sea bed, except where the water depth is less than 6 m, in which case the mid-depth station may be omitted.  Should the water depth be less than 3 m, only the mid-depth station will be monitored).

Dolphin

Line-transect Methods

Northeast Lantau survey area and Northwest Lantau survey area

Twice per month

--

Mudflat

Horseshoe crabs, seagrass beds, intertidal soft shore communities, sedimentation rates and water quality

San Tau and Tung Chung Bay

Once every 3 months

--

 

2.2                Action and Limit Levels

2.2.1       Table 2.2 presents the Action and Limit Levels for the 1-hour TSP, 24-hour TSP and noise level.

Table 2.2         Action and Limit Levels for 1-hour TSP, 24-hour TSP and Noise

Environmental Monitoring

Parameters

Monitoring Station

Action Level

Limit Level

Air Quality

1-hr TSP

AMS 5

352 µg/m3

500 µg/m3

AMS 6

360 µg/m3

24-hr TSP

AMS 5

164 µg/m3

260 µg/m3

AMS 6

173 µg/m3

Noise

Leq (30 min)

NMS 5

When one documented complaint is received

75 dB(A)

 

2.2.2       The Action and Limit Levels for water quality monitoring are given as in Table 2.3.

Table 2.3         Action and Limit Levels for Water Quality

Parameter (unit)

Water Depth

Action Level

Limit Level

Dissolved Oxygen (mg/L)

Surface and Middle

5.0

4.2 except 5 for Fish Culture Zone

Bottom

4.7

3.6

Turbidity (NTU)

Depth average

27.5 or 120% of upstream control stationˇ¦s turbidity at the same tide of the same day;

The action level has been amended to ˇ§27.5 and 120% of upstream control stationˇ¦s turbidity at the same tide of the same dayˇ¨ since 25 March 2013.

47.0 or 130% of turbidity at the upstream control station at the same tide of same day;

The limit level has been amended to ˇ§47.0 and 130% of turbidity at the upstream control station at the same tide of same dayˇ¨ since 25 March 2013.

Suspended Solid (SS) (mg/L)

Depth average

23.5 or 120% of upstream control stationˇ¦s SS at the same tide of the same day;

The action level has been amended to ˇ§23.5 and 120% of upstream control stationˇ¦s SS at the same tide of the same dayˇ¨ since 25 March 2013.

34.4 or 130% of SS at the upstream control station at the same tide of same day and 10mg/L for Water Services Department Seawater Intakes;

The limit level has been amended to ˇ§34.4 and 130% of SS at the upstream control station at the same tide of same day and 10mg/L for Water Services Department Seawater Intakesˇ¨ since 25 March 2013

Notes:

               (1)    Depth-averaged is calculated by taking the arithmetic means of reading of all three depths.

               (2)    For DO, non-compliance of the water quality limit occurs when monitoring result is lower that the limit.

               (3)    For SS & turbidity non-compliance of the water quality limits occur when monitoring result is higher than the limits.

               (4)     The change to the Action and limit Levels for Water Quality Monitoring for the EM&A works was approved by EPD on 25 March 2013. Therefore, the amended Action and Limit Levels are applied for the water monitoring results obtained on and after 25 March 2013.

2.2.3       The Action and Limit Levels for dolphin monitoring are shown in Tables 2.4 and 2.5.

Table 2.4          Action and Limit Level for Dolphin Impact Monitoring

 

North Lantau Social Cluster

NEL

NWL

Action Level

STG < 70% of baseline &
ANI < 70% of baseline

STG < 70% of baseline &
ANI  < 70% of baseline

Limit Level

STG < 40% of baseline &
ANI < 40% of baseline

Remarks:

                 (1)        STG means quarterly average encounter rate of number of dolphin sightings.

                 (2)        ANI means quarterly average encounter rate of total number of dolphins.

                 (3)        For North Lantau Social Cluster, AL will be triggered if either NEL or NWL fall below the criteria; LL will be triggered if both NEL and NWL fall below the criteria.

 

Table 2.5          Derived Value of Action Level (AL) and Limit Level (LL)

 

North Lantau Social Cluster

NEL

NWL

Action Level

STG < 4.2  & ANI < 15.5

STG < 6.9 & ANI < 31.3

Limit Level

(STG < 2.4 & ANI < 8.9) and (STG < 3.9 & ANI < 17.9)

Remarks:

                 (1)        STG means quarterly average encounter rate of number of dolphin sightings.

                 (2)        ANI means quarterly average encounter rate of total number of dolphins.

                 (3)        For North Lantau Social Cluster, AL will be triggered if either NEL or NWL fall below the criteria; LL will be triggered if both NEL and NWL fall below the criteria.

 

2.3                Event Action Plans

2.3.1      The Event Actions Plans for air quality, noise, water quality and dolphin monitoring are annexed in Appendix D.

2.4                Mitigation Measures

2.4.1       Environmental mitigation measures for the contract were recommended in the approved EIA Report.  Appendix E lists the recommended mitigation measures and the implementation status. 

3        Environmental Monitoring and Audit

3.1                Implementation of Environmental Measures

3.1.1       In response to the site audit findings, the Contractor have rectified all observations identified in environmental site inspections undertaken during the reporting period. Details of site audit findings and the corrective actions during the reporting period are presented in Appendix F.

3.1.2       A summary of the Implementation Schedule of Environmental Mitigation Measures (EMIS) is presented in Appendix E. 

3.1.3       Regular marine travel route for marine vessels were implemented properly in accordance to the submitted plan and relevant records were kept properly.

3.1.4       Dolphin Watching Plan was implemented during the reporting period. No dolphins inside the silt curtain were observed. The relevant records were kept properly. 

3.2                Air Quality Monitoring Results

3.2.1       The monitoring results for 1-hour TSP and 24-hour TSP are summarized in Tables 3.1 and 3.2 respectively. Detailed impact air quality monitoring results and relevant graphical plots are presented in Appendix G.

Table 3.1         Summary of 1-hour TSP Monitoring Results Obtained During the Reporting Period

Reporting Period

Monitoring

Station

Average (mg/m3)

Range (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

June 2016

AMS5

93

83 - 108

352

500

AMS6

98

84 - 153

360

July 2016

AMS5

122

76 - 421

352

AMS6

98

76 - 153

360

August 2016

AMS5

90

75-104

352

AMS6

99

82-136

360

 

 

 

 

 

 

 

 

 

 

 

Table 3.2         Summary of 24-hour TSP Monitoring Results Obtained During the Reporting Period

Reporting Period

Monitoring

Station

Average (mg/m3)

Range (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

June 2016

AMS5

36

22 - 79

164

260

AMS6

42

26 - 63

173

July 2016

AMS5

42

20 - 79

164

AMS6

39

34 - 45

173

August 2016

AMS5

39

21-55

164

AMS6

47

25-66

173

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3.2.2       During the reporting month, an Action Level exceedance of 1-hr TSP level was recorded at AMS5 (Ma Wan Chung Village) for 14 July 2016, 16:20 ˇV 17:20 hours.

3.3                Noise Monitoring Results

3.3.1       The monitoring results for construction noise are summarized in Table 3.3 and the monitoring results and relevant graphical plots for this reporting period are provided in Appendix H.

Table 3.3 Summary of Construction Noise Monitoring Results Obtained During the Reporting Period

Reporting period

Monitoring Station

Average Leq (30 mins), dB(A)*

Range of Leq (30 mins), dB(A)*

Action Level

Limit Level Leq (30 mins), dB(A)

June 2016

NMS5

65

61 ˇV 71

When one documented complaint is received

75

July 2016

58

55 ˇV 61

August 2016

58

55 ˇV 61

*A correction factor of +3dB(A) from free field to facade measurement was included. 

3.3.2       There were no Action and Limit Level exceedances for noise during daytime on normal weekdays of the reporting period.

3.3.3       Major noise sources during the noise monitoring included construction activities of the Contract and nearby traffic noise and insect noise.

3.4                Water Quality Monitoring Results

3.4.1      Impact water quality monitoring was conducted at all designated monitoring stations during the reporting period. Impact water quality monitoring results and relevant graphical plots are provided in Appendix I.

3.4.2      For marine water quality monitoring, no Action Level and Limit Level exceedances of turbidity level, dissolved oxygen level and suspended solid level were recorded during the reporting period.

3.4.3       Water quality impact sources during the water quality monitoring were the construction activities of the Contract, nearby construction activities by other parties and nearby operating vessels by other parties.

3.5                Dolphin Monitoring Results

Data Analysis

3.5.1       Distribution Analysis ˇV The line-transect survey data was integrated with the Geographic Information System (GIS) in order to visualize and interpret different spatial and temporal patterns of dolphin distribution using sighting positions.  Location data of dolphin groups were plotted on map layers of Hong Kong using a desktop GIS (ArcView© 3.1) to examine their distribution patterns in details.  The dataset was also stratified into different subsets to examine distribution patterns of dolphin groups with different categories of group sizes, young calves and activities.

3.5.2       Encounter rate analysis ˇV Encounter rates of Chinese white dolphins (number of on-effort sightings per 100 km of survey effort, and total number of dolphins sighted on-effort per 100 km of survey effort) were calculated in NEL and NWL survey areas in relation to the amount of survey effort conducted during each month of monitoring survey.  Dolphin encounter rates were calculated in two ways for comparisons with the HZMB baseline monitoring results as well as to AFCD long-term marine mammal monitoring results. 

3.5.3       Firstly, for the comparison with the HZMB baseline monitoring results, the encounter rates were calculated using primary survey effort alone, and only data collected under Beaufort 3 or below condition would be used for encounter rate analysis.  The average encounter rate of sightings (STG) and average encounter rate of dolphins (ANI) were deduced based on the encounter rates from six events during the present quarter (i.e. six sets of line-transect surveys in North Lantau), which was also compared with the one deduced from the six events during the baseline period (i.e. six sets of line-transect surveys in North Lantau). 

3.5.4       Secondly, the encounter rates were calculated using both primary and secondary survey effort collected under Beaufort 3 or below condition as in AFCD long-term monitoring study.  The encounter rate of sightings and dolphins were deduced by dividing the total number of on-effort sightings (STG) and total number of dolphins (ANI) by the amount of survey effort for the present quarterly period.

3.5.5       Quantitative grid analysis on habitat use ˇV To conduct quantitative grid analysis of habitat use, positions of on-effort sightings of Chinese White Dolphins collected during the quarterly impact phase monitoring period were plotted onto 1-km2 grids among NWL and NEL survey areas on GIS.  Sighting densities (number of on-effort sightings per km2) and dolphin densities (total number of dolphins from on-effort sightings per km2) were then calculated for each 1 km by 1 km grid with the aid of GIS.  Sighting density grids and dolphin density grids were then further normalized with the amount of survey effort conducted within each grid.  The total amount of survey effort spent on each grid was calculated by examining the survey coverage on each line-transect survey to determine how many times the grid was surveyed during the study period.  For example, when the survey boat traversed through a specific grid 50 times, 50 units of survey effort were counted for that grid.  With the amount of survey effort calculated for each grid, the sighting density and dolphin density of each grid were then normalized (i.e. divided by the unit of survey effort). 

3.5.6       The newly-derived unit for sighting density was termed SPSE, representing the number of on-effort sightings per 100 units of survey effort.  In addition, the derived unit for actual dolphin density was termed DPSE, representing the number of dolphins per 100 units of survey effort.  Among the 1-km2 grids that were partially covered by land, the percentage of sea area was calculated using GIS tools, and their SPSE and DPSE values were adjusted accordingly.  The following formulae were used to estimate SPSE and DPSE in each 1-km2 grid within the study area:

SPSE = ((S / E) x 100) / SA%

DPSE = ((D / E) x 100) / SA%

 

where        S = total number of on-effort sightings

D = total number of dolphins from on-effort sightings

E = total number of units of survey effort

SA% = percentage of sea area

3.5.7       Behavioural analysis ˇV When dolphins were sighted during vessel surveys, their behaviour was observed.  Different activities were categorized (i.e. feeding, milling/resting, traveling, socializing) and recorded on sighting datasheets.  This data was then input into a separate database with sighting information, which can be used to determine the distribution of behavioural data with a desktop GIS.  Distribution of sightings of dolphins engaged in different activities and behaviours would then be plotted on GIS and carefully examined to identify important areas for different activities of the dolphins. 

3.5.8       Ranging pattern analysis ˇV Location data of individual dolphins that occurred during the 3-month baseline monitoring period were obtained from the dolphin sighting database and photo-identification catalogue.  To deduce home ranges for individual dolphins using the fixed kernel methods, the program Animal Movement Analyst Extension, was loaded as an extension with ArcView© 3.1 along with another extension Spatial Analyst 2.0.  Using the fixed kernel method, the program calculated kernel density estimates based on all sighting positions, and provided an active interface to display kernel density plots.  The kernel estimator then calculated and displayed the overall ranging area at 95% UD level.

Summary of Survey Effort and Dolphin Sightings

3.5.9       During the period of June to August 2016, six sets of systematic line-transect vessel surveys were conducted to cover all transect lines in NWL and NEL survey areas twice per month.

3.5.10    From these surveys, a total of 897.06 km of survey effort was collected, with 92.5% of the total survey effort being conducted under favourable weather conditions (i.e. Beaufort Sea State 3 or below with good visibility).  Among the two areas, 341.80 km and 555.26 km of survey effort were conducted in NEL and NWL survey areas respectively. 

3.5.11    The total survey effort conducted on primary lines was 648.70 km, while the effort on secondary lines was 248.36 km.  Survey effort conducted on both primary and secondary lines were considered as on-effort survey data.  A summary table of the survey effort is shown in Annex I of Appendix J.

3.5.12    During the six sets of monitoring surveys in June to August 2016, a total of ten groups of 34 Chinese White Dolphins were sighted.  A summary table of the dolphin sightings is shown in Annex II of Appendix J.

3.5.13    For the present quarterly period, seven of the ten dolphin sightings were made during on-effort search, while all seven on-effort dolphin sightings were made on primary lines.  In addition, all except one dolphin group were sighted in NWL, while an off-effort sighting of a lone dolphin was made on June 6th in NEL.  In fact, since August 2014, only two sightings of two lone dolphins were made respectively in NEL during HKLR03 monitoring surveys.

Distribution

3.5.14    Distribution of dolphin sightings made during monitoring surveys in June to August 2016 is shown in Figure 1 of Appendix J.

3.5.15    Dolphin sightings made in the present quarter were mainly located to the east of Lung Kwu Chau and to the west of Sha Chau near western territorial boundary (Figure 1 of Appendix J).  Two sightings were made to the west of Shum Wat very close to the Hong Kong Link Road alignment at the southwestern corner of NWL survey area (Figure 1 of Appendix J).  The lone dolphin sighted in NEL was located between Shum Shui Kok and Yam O (Figure 1 of Appendix J).

3.5.16    All dolphin sightings were located far away from the HKBCF and HKLR03 reclamation sites as well as along the alignment of Tuen Mun-Chek Lap Kok Link (TMCLKL).  However, two dolphin groups were located adjacent to the HKLR alignment (Figure 1 of Appendix J).

3.5.17    Sighting distribution of dolphins during the present impact phase monitoring period (June to August 2016) was drastically different from the one during the baseline monitoring period (September to November 2011).  In the present quarter, dolphins have almost disappeared from the NEL region with the exception of a lone dolphin occurred near Shum Shui Kok (Figure 1 of Appendix J).  This was in stark contrast to their frequent occurrence around the Brothers Islands, near Shum Shui Kok and in the vicinity of HKBCF reclamation site during the baseline period (Figure 1 of Appendix J).  The nearly complete abandonment of NEL region by the dolphins has been consistently recorded in the past 14 quarters of HKLR03 monitoring, which has resulted in zero to extremely low dolphin encounter rates in this area.

3.5.18    In NWL survey area, dolphin occurrence was also very different between the baseline and impact phase periods.  During the present impact monitoring period, much fewer dolphins occurred in this survey area (mostly to the east of Lung Kwu Chau and west of Sha Chau) than during the baseline period, when many dolphin groups were frequently sighted between Lung Kwu Chau and Black Point, around Sha Chau, near Pillar Point and to the west of the Chek Lap Kok Airport (Figure 1 of Appendix J). 

3.5.19    Another comparison in dolphin distribution was made between the four quarterly periods of summer months in 2013-16 (Figure 2 of Appendix J).  Among the four summer periods, dolphins were regularly sighted throughout the North Lantau region in 2013, but their usage there has gradually diminished in 2014 and subsequently to a very low level in 2015 and 2016 (Figure 2 of Appendix J).

Encounter Rate

3.5.20    During the present three-month study period, the encounter rates of Chinese White Dolphins deduced from the survey effort and on-effort sighting data from the primary transect lines under favourable conditions (Beaufort 3 or below) for each set of the surveys in NEL and NWL are shown in Table 3.4.  The average encounter rates deduced from the six sets of surveys were also compared with the ones deduced from the baseline monitoring period (September ˇV November 2011) (See Table 3.5).

3.5.21    To facilitate the comparison with the AFCD long-term monitoring results, the encounter rates were also calculated for the present quarter using both primary and secondary survey effort.  The encounter rates of sightings (STG) and dolphins (ANI) in NWL were 1.43 sightings and 6.34 dolphins per 100 km of survey effort respectively, while the encounter rates of sightings (STG) and dolphins (ANI) in NEL were both nil for this quarter.

Table 3.4         Dolphin Encounter Rates (Sightings Per 100 km of Survey Effort) During Reporting Period (June to August 2016) 

Survey Area

Dolphin Monitoring

Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)

Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of surve
y effort)

Primary Lines Only

Primary Lines Only

Northeast  Lantau

Set 1 (1 & 6 Jun 2016)

0.00

0.00

Set 2 (13 & 17 Jun 2016)

0.00

0.00

Set 3 (5 & 12 Jul 2016)

0.00

0.00

Set 4 (18 & 27 Jul 2016)

0.00

0.00

Set 5 (5 & 9 Aug 2016)

0.00

0.00

Set 6 (17 & 23 Aug 2016)

0.00

0.00

Northwest Lantau

Set 1 (1 & 6 Jun 2016)

0.00

0.00

Set 2 (13 & 17 Jun 2016)

0.00

0.00

Set 3 (5 & 12 Jul 2016)

4.60

9.20

Set 4 (18 & 27 Jul 2016)

0.00

0.00

Set 5 (5 & 9 Aug 2016)

4.24

28.28

Set 6 (17 & 23 Aug 2016)

1.48

7.40

Table 3.5         Comparison of average dolphin encounter rates from impact monitoring period (June to August 2016) and baseline monitoring period (September ˇV November 2011)

Survey Area

Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)

Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)

Reporting Period

Baseline Monitoring Period

Reporting Period

Baseline Monitoring Period

Northeast Lantau

0.0

6.00 ˇÓ 5.05

0.0

22.19 ˇÓ 26.81

Northwest Lantau

1.72 ˇÓ 2.17

9.85 ˇÓ 5.85

7.48 ˇÓ 10.98

44.66 ˇÓ 29.85

Notes:
1) The encounter rates deduced from the baseline monitoring period have been recalculated based only on the survey effort and on-effort sighting data made along the primary transect lines under favourable conditions.

2) ˇÓ denotes the standard deviation of the average encounter rates.

 

3.5.22    In NEL, the average dolphin encounter rates (both STG and ANI) in the present three-month impact monitoring period were both zero with no on-effort sighting being made, and such extremely low occurrence of dolphins in NEL have been consistently recorded in the past fourteen quarters of HKLR03 monitoring (Table 3.6).  This is a serious concern as the dolphin occurrence in NEL in the past few years (0.0-1.0 for ER(STG) and 0.0-3.9 for ER(ANI)) have remained exceptionally low when compared to the baseline period (Table 3.6).  Dolphins have been virtually absent from NEL waters since January 2014, with only three groups of six dolphins sighted there since then despite consistent and intensive survey effort being conducted in this survey area. 

Table 3.6     Comparison of Average Dolphin Encounter Rates in Northeast Lantau Survey Area from All Quarters of Impact Monitoring Period and Baseline Monitoring Period (Sep ˇV Nov 2011)

Monitoring Period

Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)

Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)

September-November 2011 (Baseline)

6.00 ˇÓ 5.05

22.19 ˇÓ 26.81

December 2012-February 2013 (Impact)

3.14 ˇÓ 3.21

6.33 ˇÓ 8.64

March-May 2013 (Impact)

0.42 ˇÓ 1.03

0.42 ˇÓ 1.03

June-August 2013 (Impact)

0.88 ˇÓ 1.36*

3.91 ˇÓ 8.36*

September-November 2013 (Impact)

1.01 ˇÓ 1.59

3.77 ˇÓ 6.49

December 2013-February 2014 (Impact)

0.45 ˇÓ 1.10

1.34 ˇÓ 3.29

March-May 2014 (Impact)

0.00

0.00

June-August 2014 (Impact)

0.42 ˇÓ 1.04*

1.69 ˇÓ 4.15*

September-November 2014 (Impact)

0.00

0.00

December 2014-February 2015 (Impact)

0.00

0.00

March-May 2015 (Impact)

0.00

0.00

June-August 2015 (Impact)

0.44 ˇÓ 1.08*

0.44 ˇÓ 1.08*

September-November 2015 (Impact)

0.00

0.00

December 2015-February 2016 (Impact)

0.00

0.00

March-May 2016 (Impact)

0.00

0.00

June-August 2016 (Impact)

0.00*

0.00*

Notes:
1) The encounter rates deduced from the baseline monitoring period have been recalculated based only on survey effort and on-effort sighting data made along the primary transect lines under favourable conditions.

2) ˇÓ denotes the standard deviation of the average encounter rates.

3) The encounter rates in summer months were in blue and marked with asterisk.

 

3.5.23    On the other hand, the average dolphin encounter rates (STG and ANI) in NWL during the present impact phase monitoring period (reductions of 82.5% and 83.3% respectively) were only small fractions of the ones recorded during the three-month baseline period, indicating a dramatic decline in dolphin usage of this survey area as well during the present impact phase period (Table 3.7). 

3.5.24    During the same summer quarters, dolphin encounter rates in NWL during 2016 reached to the lowest point among the four summer periods, and were much lower than the ones recorded in 2013 and 2014 (Table 3.7).  Such temporal trend should be closely monitored in the upcoming monitoring quarters.

 

 

Table 3.7    Comparison of Average Dolphin Encounter Rates in Northwest Lantau Survey Area from All Quarters of Impact Monitoring Period and Baseline Monitoring Period (Sep ˇV Nov 2011)

Monitoring Period

Encounter rate (STG)            (no. of on-effort dolphin sightings per 100 km of survey effort)

Encounter rate (ANI)              (no. of dolphins from all on-effort sightings per 100 km of survey effort)

September-November 2011 (Baseline)

9.85 ˇÓ 5.85

44.66 ˇÓ 29.85

December 2012-February 2013 (Impact)

8.36 ˇÓ 5.03

35.90 ˇÓ 23.10

March-May 2013 (Impact)

7.75 ˇÓ 3.96

24.23 ˇÓ 18.05

June-August 2013 (Impact)

6.56 ˇÓ 3.68*

27.00 ˇÓ 18.71*

September-November 2013 (Impact)

8.04 ˇÓ 1.10

32.48 ˇÓ 26.51

December 2013-February 2014 (Impact)

8.21 ˇÓ 2.21

32.58 ˇÓ 11.21

March-May 2014 (Impact)

6.51 ˇÓ 3.34

19.14 ˇÓ 7.19

June-August 2014 (Impact)

4.74 ˇÓ 3.84*

17.52 ˇÓ 15.12*

September-November 2014 (Impact)

5.10 ˇÓ 4.40

20.52 ˇÓ 15.10

December 2014-February 2015 (Impact)

2.91 ˇÓ 2.69

11.27 ˇÓ 15.19

March-May 2015 (Impact)

0.47 ˇÓ 0.73

2.36 ˇÓ 4.07

June-August 2015 (Impact)

2.53 ˇÓ 3.20*

9.21 ˇÓ 11.57*

September-November 2015 (Impact)

3.94 ˇÓ 1.57

21.05 ˇÓ 17.19

December 2015-February 2016 (Impact)

2.64 ˇÓ 1.52

10.98 ˇÓ 3.81

March-May 2016 (Impact)

0.98 ˇÓ 1.10

4.78 ˇÓ 6.85

June-August 2016 (Impact)

1.72 ˇÓ 2.17*

7.48 ˇÓ 10.98*

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Notes:

1) The encounter rates deduced from the baseline monitoring period have been recalculated based only on survey effort and on-effort sighting data made along the primary transect lines under favourable conditions.

2) ˇÓ denotes the standard deviation of the average encounter rates.

3) The encounter rates in summer months were in blue and marked with asterisk.

 

3.5.25    As discussed recently in Hung (2016), the dramatic decline in dolphin usage of NEL waters in the past few years (including the declines in abundance, encounter rate and habitat use in NEL, as well as shifts of individual core areas and ranges away from NEL waters) was possibly related to the HZMB construction works that were commenced since 2012.  It appeared that such noticeable decline has already extended to NWL waters progressively in the past few years.

3.5.26    A two-way ANOVA with repeated measures and unequal sample size was conducted to examine whether there were any significant differences in the average encounter rates between the baseline and impact monitoring periods.  The two variables that were examined included the two periods (baseline and impact phases) and two locations (NEL and NWL). 

3.5.27    For the comparison between the baseline period and the present quarter (fifteenth quarter of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.0031 and 0.0227 respectively.  If the alpha value is set at 0.05, significant differences were detected between the baseline and present quarters in both the average dolphin encounter rates of STG and ANI. .

3.5.28    For the comparison between the baseline period and the cumulative quarters in impact phase (i.e. first fifteen quarters of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.000009 and 0.000001 respectively.  Even if the alpha value is set at 0.00001, significant differences were still detected in both the average dolphin encounter rates of STG and ANI (i.e. between the two periods and the locations).

3.5.29    As indicated in both dolphin distribution patterns and encounter rates, dolphin usage has been significantly reduced in both NEL and NWL survey areas during the present quarterly period, and such low occurrence of dolphins has also been consistently documented in previous quarters.  This raises serious concern, as the timing of the decline in dolphin usage in North Lantau waters coincided well with the construction schedule of the HZMB-related projects (Hung 2016).

3.5.30    To ensure the continuous usage of North Lantau waters by the dolphins, every possible measure should be implemented by the contractors and relevant authorities of HZMB-related works to minimize all disturbances to the dolphins.

Group Size

3.5.31    Group size of Chinese White Dolphins ranged from one to eleven individuals per group in North Lantau region during June to August 2016.  The average dolphin group sizes from these three months were compared with the ones deduced from the baseline period in September to November 2011, as shown in Table 3.8.

Table 3.8         Comparison of Average Dolphin Group Sizes between Reporting Period (Jun 2016 ˇV Aug 2016) and Baseline Monitoring Period (Sep ˇV Nov 2011)

Survey Area

Average Dolphin Group Size

Reporting Period

Baseline Monitoring Period

Overall

3.40 ˇÓ 3.34 (n = 10)

3.72 ˇÓ 3.13 (n = 66)

Northeast Lantau

1.00 (n = 1)

3.18 ˇÓ 2.16 (n = 17)

Northwest Lantau

3.67 ˇÓ 3.43 (n = 9)

3.92 ˇÓ 3.40 (n = 49)

 

 

 

 

 

 

 

 

 

 

Note:

1)     ˇÓ denotes the standard deviation of the average group size.

3.5.32    The average dolphin group size in NWL waters during June to August 2016 was slightly lower than the one recorded during the three-month baseline period (Table 3.8). Most of these dolphin groups were composed of 1-3 individuals only, while there were two medium-sized groups of five and seven individuals respectively, and one large group of eleven individuals.

3.5.33    As there was only one single dolphin sighted in NEL waters during this quarter, the average group size was much lower than the one recorded during the baseline period (Table 3.8).

3.5.34    Distribution of the larger dolphin groups (i.e. five individuals or more per group) during the present quarter is shown in (Figure 3 of Appendix J), with comparison to the one in baseline period.  During the summer months of 2016, the two medium-sized groups were sighted near Pak Chau and to the east of Lung Kwu Chau respectively, while one large group of eleven individuals was sighted to the west of Sha Chau near the western territorial boundary (Figure 3 of Appendix J). Such distribution pattern was very different from the baseline period, when the larger dolphin groups were more frequently sighted and more evenly distributed in NWL waters, with a few more sighted in NEL waters. (Figure 3 of Appendix J).

Habitat Use

3.5.35    From June to August 2016, the more important habitats utilized by Chinese White Dolphins were located to the west of Sha Chau at the western territorial boundary, as well as to the northeast of Lung Kwu Chau (Figures 4a and 4b of Appendix J).  One grid located to the west of Shum Wat overlapped with the HKLR09 alignment also recorded moderate density of dolphins.  On the contrary, all grids near HKLR03/HKBCF reclamation sites as well as TMCLKL alignment did not record any presence of dolphins at all during on-effort search in the present quarterly period (Figures 4b of Appendix J).

3.5.36    It should be emphasized though that the amount of survey effort collected in each grid during the three-month period was fairly low (6-12 units of survey effort for most grids), and therefore the habitat use pattern derived from the three-month dataset should be treated with caution.  A more complete picture of dolphin habitat use pattern should be examined when more survey effort for each grid will be collected throughout the impact phase monitoring programme.

3.5.37    When compared with the habitat use patterns during the baseline period, dolphin usage in NEL and NWL has drastically diminished in both areas during the present impact monitoring period (Figure 5 of Appendix J). During the baseline period, many grids between Siu Mo To and Shum Shui Kok in NEL recorded moderately high to high dolphin densities, which was in stark contrast to the complete absence of dolphins there during the present impact phase period (Figure 5 of Appendix J). 

3.5.38    The density patterns were also very different in NWL between the baseline and impact phase monitoring periods, with higher dolphin usage throughout the area, especially around Sha Chau, near Black Point, to the west of the airport, as well as between Pillar Point and airport platform during the baseline period.  In contrast, the only areas with moderate to high dolphin densities were restricted to the waters near Sha Chau and Lung Kwu Chau during the present impact phase period. (Figure 5 of Appendix J). 

Mother-calf Pairs

3.5.39    During the present quarterly period, neither unspotted calf nor unspotted juvenile was sighted with any female in the North Lantau region.

3.5.40    The absence of young calves in the past three consecutive quarters was in stark contrast to their regular occurrence in North Lantau waters during the baseline period.  This should be of a serious concern, and the occurrence of young calves in North Lantau waters should be closely monitored in the upcoming quarters.

Activities and Associations with Fishing Boats

3.5.41    Only one of the ten dolphin groups were engaged in socializing activity, while none of them was engaged in feeding, traveling or milling/resting activity during the three-month study period.

3.5.42    The percentage of sightings associated with socializing activities (10.0%) was higher than the one recorded during the baseline period (5.4%).  However, it should be noted the sample size on total numbers of dolphin sightings during the present quarter (ten dolphin groups) was much lower than the baseline period (66 dolphin groups).

3.5.43    Distribution of dolphins engaged in various activities during the present impact phase period and the baseline period is shown in Figure 6 of Appendix J.  The only dolphin group engaged in socializing activity was sighted to the west of Shum Wat near the HKLR09 alignment during the present quarterly period, which was very different from the baseline period when various dolphin activities occurred throughout the North Lantau region. (Figure 6 of Appendix J).

3.5.44    As consistently recorded in the past monitoring quarters, none of the ten dolphin groups was found to be associated with any operating fishing vessel in North Lantau waters during the present impact phase period.

Summary Photo-identification works

3.5.45    From June to August 2016, over 1,200 digital photographs of Chinese White Dolphins were taken during the impact phase monitoring surveys for the photo-identification work.

3.5.46    In total, 15 individuals sighted 15 times altogether were identified (see summary table in Annex III of Appendix J and photographs of identified individuals in Annex IV of Appendix J).  All of these re-sightings were made in NWL.

3.5.47    Notably, three of these 15 individuals (NL104, NL136 and NL302) were also sighted in West Lantau waters during the HKLR09 monitoring surveys from June to August 2016.  Moreover, one individual (NL150) was sighted in both NWL and SWL survey areas during the same quarter, showing extensive individual movement between different survey areas.

Individual range use

3.5.48    Ranging patterns of the 15 individuals identified during the three-month study period were determined by fixed kernel method, and are shown in Annex V of Appendix J.

3.5.49    All identified dolphins sighted in the present quarter were utilizing NWL waters only, but have completely avoided NEL waters where many of them have utilized as their core areas in the past (Annex V of Appendix J).  This is in contrary to the extensive movements between NEL and NWL survey areas observed in the earlier impact monitoring quarters as well as the baseline period.

3.5.50    On the other hand, four individuals (NL104, NL136, NL150 and NL302) consistently utilized both North Lantau waters in the past have extended their range use to WL and SWL waters during the present quarter.  In the upcoming quarters, individual range use and movements should be continuously monitored to examine whether there has been any consistent shifts of individual home ranges from North Lantau to West or Southwest Lantau, as such shift could possibly be related to the HZMB-related construction works (see Hung 2015, 2016).

Action Level / Limit Level Exceedance

3.5.51    There was one Limit Level exceedance of dolphin monitoring for the quarterly monitoring data (between June 2016 ˇV August 2016). According to the contractorˇ¦s information, the marine activities undertaken for HKLR03 during the quarter of June 2016 ˇV August 2016 included removal of surcharge materials, temporary drainage diversion, ground investigation, box culvert diversion, construction of permanent sea wall and maintenance of silt curtain.

3.5.52    There is no evidence showing the current LL non-compliance directly related to the construction works of HKLR03 (where the amounts of working vessels for HKLR03 have been decreasing), although the generally increased amount of vessel traffic in NEL during the impact phase has been partly contributed by HKLR03 works since October 2012. It should also be noted that reclamation work under HKLR03 (adjoining the Airport Island) situates in waters which has rarely been used by dolphins in the past, and the working vessels under HKLR03 have been travelling from source to destination in accordance with the Marine Travel Route to minimize impacts on Chinese White Dolphin (CWD).  In addition, the contractor will implement proactive mitigation measures such as avoiding anchoring at Marine Departmentˇ¦s designated anchorage site ˇV Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

3.5.53    According to Monitoring of Chinese White Dolphins in Southwest Lantau Waters ˇV Fourth Quarterly Report (December 2015 to February 2016) which is available on ENPOˇ¦s website, with their primary ranges centered in North and West Lantau waters, some individuals showed apparent range shifts or extensions to Southwest Lantau waters in 2015-16.  For example, three individual dolphins (NL120, WL46 and WL221) indicated obvious shifts in their range use from NWL to West Lantau (WL) and Southwest Lantau (SWL) waters. Moreover, many individuals (e.g. NL212, NL260, WL200, SL55, WL232, WL237 and WL265) have extended their ranges from WL waters to SWL waters.  It remains to be seen whether some of these individuals have permanently shifted their ranges away from their primary ranges in North Lantau, or begin to spend more times in SWL waters as part of their ranges. 

3.5.54    ENPO updated that the Hong Kong-Zhuhai-Macao Bridge Authority (HZMBA) for the Mainland section of Hong Kong-Zhuhai-Macao Bridge (HZMB) has commenced an interim survey on fisheries resources and CWD in the Mainland waters. ENPO presented the preliminary findings of the HZMBA interim survey on CWD sighting and photo-identification works which provide solid evidence that some CWD that were previously more often sighted in HK waters have expanded their ranges into the Mainland waters, and some with reduced usage in HK waters. These preliminary data were mentioned in Monitoring of Chinese White Dolphins in Southwest Lantau Waters ˇV Fourth Quarterly Report (December 2015 to February 2016) which is available on ENPOˇ¦s website.

3.5.55    A two-way ANOVA with repeated measures and unequal sample size was conducted to examine whether there were any significant differences in the average encounter rates between the baseline and impact monitoring periods.  The two variables that were examined included the two periods (baseline and impact phases) and two locations (NEL and NWL). 

3.5.56    For the comparison between the baseline period and the present quarter (fifteenth quarter of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.0031 and 0.0227 respectively.  If the alpha value is set at 0.05, significant differences were detected between the baseline and present quarters in both the average dolphin encounter rates of STG and ANI.

3.5.57    For comparison between the baseline period and the cumulative quarters in impact phase (i.e. first fifteen quarters of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.000009 and 0.000001 respectively.  Even if the alpha value is set at 0.00001, significant differences were still detected in both the average dolphin encounter rates of STG and ANI (i.e. between the two periods and the locations).

3.5.58    The AFCD monitoring data during June to August 2016 has been reviewed by the dolphin specialist.  During the same quarter, no dolphin was sighted from 78.80 km of survey effort on primary lines in NEL, while three groups of 19 dolphins were sighted from 123.40 km of survey effort on primary lines in NWL. This review has confirmed that the extremely low occurrence of dolphins reported by the HKLR03 monitoring surveys in summer 2016 in NEL and NWL survey area is accurate.

3.5.59    All dolphin protective measures are fully and properly implemented in accordance with the EM&A Manual. According to the Marine Travel Route Plan, the travelling speed of vessels must not exceed 5 knots when crossing the edge of the proposed marine park. The Contractor will continue to provide training for skippers to ensure that their working vessels travel from source to destination to minimize impacts on Chinese White Dolphin and avoid anchoring at Marine Departmentˇ¦s designated anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. Also, it is recommended to complete the marine works of the Contract as soon as possible so as to reduce the overall duration of impacts and allow the dolphins population to recover as early as possible.

3.5.60    All dolphin protective measures are fully and properly implemented in accordance with the EM&A Manual. According to the Marine Travel Route Plan, the travelling speed of vessels must not exceed 5 knots when crossing the edge of the proposed marine park. The Contractor will continue to provide training for skippers to ensure that their working vessels travel from source to destination to minimize impacts on Chinese White Dolphin and avoid anchoring at Marine Departmentˇ¦s designated anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. Also, it is recommended to complete the marine works of the Contract as soon as possible so as to reduce the overall duration of impacts and allow the dolphins population to recover as early as possible.

3.5.61    A meeting was held on 14 October 2016 with attendance of representative of ENPO, Resident Site Staff (RSS), Environmental Team (ET) and dolphin specialist for Contract Nos. HY/2010/02, HY/2011/03, HY/2012/07, HY/2012/08. The discussion/recommendation as recorded in the minutes of the meeting, which might be relevant to HKLR03 Contract are summarized below.

3.5.62    It was concluded that the HZMB works is one of the contributing factors affecting the dolphins. It was also concluded the contribution of impacts due to the HZMB works as a whole (or individual marine contracts) cannot be quantified nor separate from the other stress factors.

3.5.63    The dolphin specialists of the projects confirmed that the CWD sighting around the North of Sha Chau and Lung Kwu Chau Marine Park (SCLKCMP) has significantly decreased, and it was apparently related to the re-routing of high speed ferry (HSF) from Skypier.

3.5.64    It was reminded that the ETs shall keep reviewing the implementation status of the dolphin related mitigation measures and remind the contractor to ensure the relevant measures were fully implemented.

3.5.65    It was recommended that the marine works of HZMB projects should be completed as soon as possible so as to reduce the overall duration of impacts and allow the dolphins population to recover as early as possible.

3.5.66    It was also recommended that the marine works footprint (e.g., reduce the size of peripheral silt curtain) and vessels for the marine works should be reduced as much as possible, and vessels idling / mooring in other part of the North Lantau shall be avoided whenever possible.

3.5.67    It was suggested that the protection measures (e.g., speed limit control) for the proposed Brothers Marine Park (BMP) shall be brought forward as soon as possible before its establishment so as to provide a better habitat for dolphin recovery. It was noted that under the Regular Marine Travel Route Plan, the contractors have committed to reduce the vessel speed in BMP. HyD updated that the draft map of the proposed BMP was gazetted in February 2016. ENPO updated that the BMP was approved by the Chief Executive in the Executive Council in August 2016. The ETs were reminded to update the BMP boundary in the Regular Marine Travel Route Plan.

3.5.68    There was a discussion on exploring possible further mitigation measures, for example, controlling the underwater noise. It was noted that the EIA reports for the projects suggested several mitigation measures, all of which have been implemented.

3.6                Mudflat Monitoring Results

Sedimentation Rate Monitoring

3.6.1       The baseline sedimentation rate monitoring was in September 2012 and impact sedimentation rate monitoring was undertaken on 2 June 2016. The mudflat surface levels at the four established monitoring stations and the corresponding XYZ HK1980 GRID coordinates are presented in Table 3.9 and Table 3.10.


 

Table 3.9          Measured Mudflat Surface Level Results

Baseline Monitoring
(September 2012)

Impact Monitoring
(
March 2016)

Monitoring Station

Easting
(m)

Northing (m)

Surface Level
(mPD)

Easting
(m)

Northing (m)

Surface Level

(mPD)

S1

810291.160

816678.727

0.950

810291.141

816678.735

1.073

S2

810958.272

815831.531

0.864

810958.261

815831.556

0.989

S3

810716.585

815953.308

1.341

810716.670

815953.302

1.468

S4

811221.433

816151.381

0.931

811221.408

816151.338

1.104

Table 3.10       Comparison of Measurement  

Comparison of measurement

Remarks and Recommendation

Monitoring Station

Easting
(m)

Northing (m)

Surface Level
(mPD)

S1

-0.019

0.008

0.123

Level continuously increased

S2

-0.011

0.025

0.125

Level continuously increased

S3

0.085

-0.006

0.127

Level continuously increased

S4

-0.025

0.006

0.173

Level continuously increased

 

3.6.2       This measurement result was generally and relatively higher than the baseline measurement at S1, S2, S3 and S4. The mudflat level is continuously increased.

Water Quality Monitoring

3.6.3       The mudflat monitoring covered water quality monitoring data.  Reference was made to the water quality monitoring data of the representative water quality monitoring station (i.e. SR3) as in the EM&A Manual.  The water quality monitoring location (SR3) is shown in Figure 2.1. 

3.6.4       Impact water quality monitoring in San Tau (monitoring station SR3) was conducted in June 2016. The monitoring parameters included dissolved oxygen (DO), turbidity and suspended solids (SS).

3.6.5       The Impact monitoring result for SR3 were extracted and summarised below:

Table 3.11  Impact Water Quality Monitoring Results (Depth Average)

Date

Mid Ebb Tide

Mid Flood Tide

DO (mg/L)

Turbidity (NTU)

SS (mg/L)

DO (mg/L)

Turbidity (NTU)

SS (mg/L)

1-Jun-16

9.01

6.85

4.80

10.30

5.35

10.60

3-Jun-16

9.55

6.45

3.15

8.60

8.70

7.60

6-Jun-16

5.79

5.75

5.15

5.66

5.70

5.50