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. 15 (March to May 2016)

 

25 October 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. 3

2.3                    Event Action Plans. 5

2.4                    Mitigation Measures. 5

3....... Environmental Monitoring and Audit 5

3.1                    Implementation of Environmental Measures. 5

3.2                    Air Quality Monitoring Results. 6

3.3                    Noise Monitoring Results. 6

3.4                    Water Quality Monitoring Results. 7

3.5                    Dolphin Monitoring Results. 7

3.6                    Mudflat Monitoring Results. 17

3.7                    Solid and Liquid Waste Management Status. 28

3.8                    Environmental Licenses and Permits. 28

4....... Environmental Complaint and Non-compliance. 29

4.1                    Environmental Exceedances. 29

4.2                    Summary of Environmental Complaint, Notification of Summons and Successful Prosecution. 29

5....... Comments, Recommendations and Conclusion.. 31

5.1                    Comments. 31

5.2                    Recommendations. 32

5.3                    Conclusions. 32

 

 

 

 

 

 

 

 

 

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 ¡§Notification of Environmental Quality Limit Exceedances¡¨ and Record of ¡§Notification of Summons and Prosecutions¡¨

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 ¡§Designated Projects¡¨, 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 fifteenth 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 March 2016 to 31 May 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

March 2016

April 2016

May 2016

Air Quality

1-hr TSP

1, 7, 11, 17 23 and 29

1, 7, 12, 18, 22 and 28

4, 10, 16, 20, 25 and 31

24-hr TSP

4, 10, 16, 21, 24 and 30  

5, 11, 15, 21 and 27

AMS5: 3, 9, 13, 19 and 24

AMS6: 3, 9, 13, 19, 24 and 30

Noise

1, 7, 17, 23 and 29

7, 12, 18 and 28

4, 10, 16, 25 and 31

Water Quality

2, 4, 7, 9, 11, 14, 16, 18, 21, 23, 25, 28 and 30

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

2, 4, 6, 9, 11, 13, 16, 18, 20, 23, 25 and 30

Chinese White Dolphin

7, 11, 22 and 23

5, 12, 15 and 19

3, 12, 17 and 26

Mudflat Monitoring (Ecology)

8, 12, 13, 20, 22 and 26

--

--

Mudflat Monitoring (Sedimentation rate)

9

--

--

Site Inspection

3, 9, 16, 23 and 29

6, 14, 20 and 29

4, 11, 18 and 27

 

Due to weather condition/boat availability, the dolphin monitoring schedule was rescheduled from 14 March 2016 to 11 March 2016, 21 March 2016 to 22 March 2016, from 11 April 2016 to 12 April 2016, from 6 May 2016 to 12 May 2016, from 16 May 2016 to 17 May 2016 and from 23 May 2016 to 26 May 2016.

Due to change of weather condition, mudflat monitoring (ecology) was rescheduled from 6 March 2016 to 8 March and from 23 March 2016 to 26 March 2016.

Due to power interruption and malfunction of HVS at station AMS5, the 24-hr TSP monitoring at AMS5 on 30 May 2016 was cancelled. A competent person was arranged to repair the HVS and check the power supply provided for HVS on 7 June 2016.

As Strong Wind Signal No.3 was hoisted by Hong Kong Observatory on 27 May 2016, water quality monitoring on 27 May 2016 was cancelled for safety reason. However, due to safety reason, the water quality monitoring was not carried out on 28 May 2016 because thunderstorm warming was hoisted by Hong Kong Observatory on that day.

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

0

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 (Mar 2016 to May 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 were no complaints received in relation to the environmental impacts during the reporting period.

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 team¡¦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

1.1.1       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 ¡§Designated Projects¡¨, 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 fifteenth 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 March 2016 to 31 May 2016.

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 Contractor¡¦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

Portion X

Construction of box culvert PR14

Portion X

Excavation for diversion of culvert PR10

Portion X

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

Portion X

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

Portion X

Excavation for HKBCF to Airport Tunnel

Portion X

Jet Grouting works & Sheet Piling Works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel)

Portion X

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

Portion X

Sheet Piling Works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel)

Portion X

Socket H-Piling Works for HKBCF to Airport Tunnel East (Cut &Cover Tunnel)

Portion X

Pipe piling works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel)

Portion X

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

Portion X & Y

Pre-bored works for excavation in Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X & Y

Superstructure works for Scenic Hill Tunnel West Portal Ventilation building

West Portal

Excavation for Scenic Hill Tunnel

West Portal

Works for diversion

Kwo Lo Wan Road and 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

Excavation and lateral support works at shaft 3 extension north shaft

Kwo Lo Wan Road

Pipe roofing drilling / Mined Tunnel excavation underneath Airport Road

Airport Road

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

Airport Road

Utility culvert excavation

Portion Y

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

Portion Y

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

 

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

¡P    Depth

¡P    Temperature

¡P    Salinity

¡P    Dissolved Oxygen (DO)

¡P    Suspended Solids (SS)

¡P    DO Saturation

¡P    Turbidity

¡P    pH

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

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

¡P    Sensitive Receiver Stations:
SR3, SR4, SR5, SR10A & SR10B

Three times per week during mid-ebb and mid-flood tides (within ¡Ó 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

--

 

2.2.1       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 station¡¦s turbidity at the same tide of the same day;

The action level has been amended to ¡§27.5 and 120% of upstream control station¡¦s turbidity at the same tide of the same day¡¨ 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 ¡§47.0 and 130% of turbidity at the upstream control station at the same tide of same day¡¨ since 25 March 2013.

Suspended Solid (SS) (mg/L)

Depth average

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

The action level has been amended to ¡§23.5 and 120% of upstream control station¡¦s SS at the same tide of the same day¡¨ 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 ¡§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 Intakes¡¨ 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. 

3.2.1       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)

March 2016

AMS5

169

117 ¡V 232

352

500

AMS6

160

107 - 285

360

April 2016

AMS5

140

90 - 233

352

AMS6

140

79 - 236

360

May 2016

AMS5

116

80 - 222

352

AMS6

117

86 - 184

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)

March 2016

AMS5

48

19 - 112

164

260

AMS6

61

29 - 143

173

April 2016

AMS5

46

26 - 82

164

AMS6

59

36 - 89

173

May 2016

AMS5

39

21 - 60

164

AMS6

58

32 - 88

173

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3.2.2       There were no Action and Limit Level exceedances of 1-hr TSP and 24-hr TSP were recorded at AMS5 and AMS6 during the reporting period.

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)

March 2016

NMS5

60

57 - 73

When one documented complaint is received

75

April 2016

61

60 - 63

May 2016

62

58 - 67

*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.

3.4.1       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.

3.4.1      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.

3.4.2       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.

Data Analysis

3.5.1       Distribution Analysis ¡V 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 ¡V 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 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 ¡V 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 Northwest Lantau (NWL) and Northeast (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 ¡V 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 ¡V 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 March to May 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 896.56 km of survey effort was collected, with 90.3% 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, 341.16 km and 555.40 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 657.94 km, while the effort on secondary lines was 238.62 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 March to May 2016, a total of seven groups of 22 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, four of the seven dolphin sightings were made during on-effort search, while three of the four on-effort dolphin sightings were made on primary lines.  Moreover, all dolphin groups were sighted in NWL, but none was sighted at all in NEL. In fact, since August 2014, only one sighting of a lone dolphin was made in NEL during HKLR03 monitoring surveys.

Distribution

3.5.14    Distribution of dolphin sightings made during monitoring surveys in March to May 2016 is shown in Figure 1 of Appendix J. Dolphin sightings made in the present quarter were mostly located to the north of Lung Kwu Chau, while one sighting each was made to the southwest of Lung Kwu Chau and at the northeast corner of the airport platform respectively (Figure 1 of Appendix J). Notably, four of the five sightings located to the north of Lung Kwu Chau were all made on the same survey day.

3.5.15    One dolphin group was sighted near the HKBCF reclamation site.  On the other hand, all other dolphin sightings were made far away from the HKLR03 reclamation site, as well as along the alignments of Tuen Mun-Chek Lap Kok Link (TMCLKL) and Hong Kong Link Road (HKLR) (Figure 1 of Appendix J).

3.5.16    Sighting distribution of dolphins during the present impact phase monitoring period (March to May 2016) was drastically different from the one during the baseline monitoring period (September to November 2011).  In the present quarter, dolphins have disappeared from the NEL region, which 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).  The nearly complete abandonment of NEL region by the dolphins has been consistently recorded in the past 13 quarters of HKLR03 monitoring, which has resulted in zero to extremely low dolphin encounter rates in this area.

3.5.17    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 near Lung Kwu 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). 

3.5.18    Another comparison in dolphin distribution was made between the four quarterly periods of spring months in 2013-16 (Figure 2 of Appendix J). Among the four spring periods, dolphins were regularly sighted throughout the North Lantau region in 2013, but their usage there have been significantly reduced to a very low level in 2015 and 2016 (Figure 2 of Appendix J).


 

Encounter Rate

3.5.19    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 ¡V November 2011) (See Table 3.5).

 

Table 3.4         Dolphin Encounter Rates (Sightings Per 100 km of Survey Effort) During Reporting Period (March to May 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 (7 & 11 Mar 2016)

0.00

0.00

Set 2 (22 & 23 Mar 2016)

0.00

0.00

Set 3 (5 & 12 Apr 2016)

0.00

0.00

Set 4 (15 & 19 Apr 2016)

0.00

0.00

Set 5 (3 & 12 May 2016)

0.00

0.00

Set 6 (17 & 26 May 2016)

0.00

0.00

Northwest Lantau

Set 1 (7 & 11 Mar 2016)

0.00

0.00

Set 2 (22 & 23 Mar 2016)

1.59

4.78

Set 3 (5 & 12 Apr 2016)

2.20

17.59

Set 4 (15 & 19 Apr 2016)

2.10

6.31

Set 5 (3 & 12 May 2016)

0.00

0.00

Set 6 (17 & 26 May 2016)

0.00

0.00

 

Table 3.5         Comparison of average dolphin encounter rates from impact monitoring period (March to May 2016) and baseline monitoring period (September ¡V 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 ¡Ó 5.05

0.0

22.19 ¡Ó 26.81

Northwest Lantau

0.98 ¡Ó 1.10

9.85 ¡Ó 5.85

4.78 ¡Ó 6.85

44.66 ¡Ó 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) ¡Ó denotes the standard deviation of the average encounter rates.

 

3.5.20    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 0.83 sightings and 3.54 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.

3.5.21    In NEL, the average dolphin encounter rates (both STG and ANI in the present three-month impact monitoring period were both zero with no sighting being made, and such extremely low occurrence of dolphins in NEL have been consistently recorded in the past thirteen 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 been exceptionally low when compared to the baseline period (Table 3.6).  Dolphins have been virtually absent from NEL waters since January 2014, with only two groups of five 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 ¡V 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 ¡Ó 5.05

22.19 ¡Ó 26.81

December 2012-February 2013 (Impact)

3.14 ¡Ó 3.21

6.33 ¡Ó 8.64

March-May 2013 (Impact)

0.42 ¡Ó 1.03*

0.42 ¡Ó 1.03*

June-August 2013 (Impact)

0.88 ¡Ó 1.36

3.91 ¡Ó 8.36

September-November 2013 (Impact)

1.01 ¡Ó 1.59

3.77 ¡Ó 6.49

December 2013-February 2014 (Impact)

0.45 ¡Ó 1.10

1.34 ¡Ó 3.29

March-May 2014 (Impact)

0.00*

0.00*

June-August 2014 (Impact)

0.42 ¡Ó 1.04

1.69 ¡Ó 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 ¡Ó 1.08

0.44 ¡Ó 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*

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) ¡Ó denotes the standard deviation of the average encounter rates.

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

 

3.5.22    On the other hand, the average dolphin encounter rates (STG and ANI) in NWL during the present impact phase monitoring period (reductions of 90.1% and 89.3% 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). 

3.5.23    During the same spring quarters, the dolphin encounter rates in NWL during the spring months of 2015 and 2016 were much lower than the ones recorded in spring months of 2013 and 2014 (Table 3.7).  Such temporal trend should be closely monitored in the upcoming monitoring quarters.

3.5.24    As discussed recently in Hung (2015), 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.

 

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 ¡V 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 ¡Ó 5.85

44.66 ¡Ó 29.85

December 2012-February 2013 (Impact)

8.36 ¡Ó 5.03

35.90 ¡Ó 23.10

March-May 2013 (Impact)

7.75 ¡Ó 3.96*

24.23 ¡Ó 18.05*

June-August 2013 (Impact)

6.56 ¡Ó 3.68

27.00 ¡Ó 18.71

September-November 2013 (Impact)

8.04 ¡Ó 1.10

32.48 ¡Ó 26.51

December 2013-February 2014 (Impact)

8.21 ¡Ó 2.21

32.58 ¡Ó 11.21

March-May 2014 (Impact)

6.51 ¡Ó 3.34*

19.14 ¡Ó 7.19*

June-August 2014 (Impact)

4.74 ¡Ó 3.84

17.52 ¡Ó 15.12

September-November 2014 (Impact)

5.10 ¡Ó 4.40

20.52 ¡Ó 15.10

December 2014-February 2015 (Impact)

2.91 ¡Ó 2.69

11.27 ¡Ó 15.19

March-May 2015 (Impact)

0.47 ¡Ó 0.73*

2.36 ¡Ó 4.07*

June-August 2015 (Impact)

2.53 ¡Ó 3.20

9.21 ¡Ó 11.57

September-November 2015 (Impact)

3.94 ¡Ó 1.57

21.05 ¡Ó 17.19

December 2015-February 2016 (Impact)

2.64 ¡Ó 1.52

10.98 ¡Ó 3.81

March-May 2016 (Impact)

0.98 ¡Ó 1.10*

4.78 ¡Ó 6.85*

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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) ¡Ó denotes the standard deviation of the average encounter rates.

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

 

3.5.25    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). 

3.5.26    For the comparison between the baseline period and the present quarter (fourteenth quarter of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.0019 and 0.0173 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.

3.5.27    For comparison between the baseline period and the cumulative quarters in impact phase (i.e. first fourteen quarters of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.000019 and 0.000005 respectively.  Even if the alpha value is set at 0.00005, 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).

3.5.28    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 2015).

3.5.29    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

3.5.30    Group size of Chinese White Dolphins ranged from one to eight individuals per group in North Lantau region during March to May 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 (Mar 2016 ¡V May 2016) and Baseline Monitoring Period (Sep ¡V Nov 2011)

Survey Area

Average Dolphin Group Size

Reporting Period

Baseline Monitoring Period

Overall

3.14 ¡Ó 2.27 (n = 7)

3.72 ¡Ó 3.13 (n = 66)

Northeast Lantau

N/A

3.18 ¡Ó 2.16 (n = 17)

Northwest Lantau

3.14 ¡Ó 2.27 (n = 7)

3.92 ¡Ó 3.40 (n = 49)

 

 

 

 

 

 

 

 

 

 

 

Note:

1)     ¡Ó denotes the standard deviation of the average group size.

3.5.31    The average dolphin group size in NWL waters during March to May 2016 was slightly lower than the ones recorded during the three-month baseline period (Table 3.8). All except one dolphin groups were composed of 1-3 individuals only, while only one group was moderately large with eight individuals.

3.5.32    Distribution of the lone larger dolphin group (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 spring months of 2016, the only larger dolphin group was sighted to the southwest of Lung Kwu Chau (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

3.5.33    From March to May 2016, the only area being utilized by Chinese White Dolphins was to the north and southwest of Lung Kwu Chau (Figures 4a and 4b of Appendix J). All grids near HKLR03/HKBCF reclamation sites as well as HKLR09/ TMCLKL alignments did not record any presence of dolphins at all during on-effort search in the present quarterly period (Figures 4b of Appendix J).

3.5.34    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.

3.5.35    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). 

3.5.36    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 area with moderate to high dolphin densities was restricted to the waters near Lung Kwu Chau during the present impact phase period (Figure 5 of Appendix J). 

Mother-calf Pairs

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

3.5.38    The absence of young calves in the present quarter 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

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

3.5.40    The percentage of sightings associated with feeding activities (14.3%) was similar to the one recorded during the baseline period (11.6%).  However, it should be noted the sample sizes on total numbers of dolphin sightings during the present quarter (seven dolphin groups) was much lower than the baseline period (66 dolphin groups).

3.5.41    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 feeding activity was sighted to the north of Lung Kwu Chau 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).

3.5.42    As consistently recorded in the past monitoring quarters, none of the seven 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

3.5.43    From March to May 2016, over 800 digital photographs of Chinese White Dolphins were taken during the impact phase monitoring surveys for the photo-identification work.

3.5.44    In total, 16 individuals sighted 18 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.

3.5.45    The majority of identified individuals were sighted only once during the three-month period, with the exception of two individuals (NL48 and NL285) being sighted twice in the present quarter.

3.5.46    Notably, two of these 16 individuals (NL123 and NL320) were also sighted in West Lantau waters during the HKLR09 monitoring surveys from March to May 2016.

Individual range use

3.5.47    Ranging patterns of the 16 individuals identified during the three-month study period were determined by fixed kernel method, and are shown in Annex V of Appendix J.

3.5.48    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.

3.5.49    On the other hand, two individuals (NL123 and NL320) consistently utilized both North Lantau waters in the past have extended their range use to WL 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).

 

Action Level / Limit Level Exceedance[OS1] [OS2] [OS3] 

3.5.50    There was one Limit Level exceedance of dolphin monitoring for the quarterly monitoring data (between March 2016 ¡V May 2016). According to the contractor¡¦s information, the marine activities undertaken for HKLR03 during the quarter of March 2016 ¡V May 2016 included removal of surcharge materials, temporary drainage diversion, ground investigation and maintenance of silt curtain.

3.5.51    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 Department¡¦s designated anchorage site ¡V Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

3.5.52    According to Monitoring of Chinese White Dolphins in Southwest Lantau Waters ¡V Fourth Quarterly Report (December 2015 to February 2016) which is available on ENPO¡¦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. 

3.5.53    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 ¡V Fourth Quarterly Report (December 2015 to February 2016) which is available on ENPO¡¦s website.

3.5.54    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). 

3.5.55    For the comparison between the baseline period and the present quarter (fourteenth quarter of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.0019 and 0.0173 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.

3.5.56    For comparison between the baseline period and the cumulative quarters in impact phase (i.e. first fourteen quarters of the impact phase being assessed), the p-values for the differences in average dolphin encounter rates of STG and ANI were 0.000019 and 0.000005 respectively.  Even if the alpha value is set at 0.00005, 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).

3.5.57    The AFCD monitoring data during March to May 2016 has been reviewed by the dolphin specialist.  During the same quarter, no dolphin was sighted from 159.50 km of survey effort on primary lines in NEL, while two groups of two dolphins were sighted from 186.34 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 spring 2016 in NEL and NWL survey area is accurate.

3.5.58    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 Department¡¦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.

3.5.59    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 Department¡¦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    A meeting was held on 22 July 2016 with attendance of representative of Highways Department (HyD), 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. Also, main Contractor for Contract Nos. HY/2012/08 attended the meeting. The discussion/recommendation as recorded in the minutes of the meeting, which might be relevant to HKLR03 Contract are summarized below.

3.5.61    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.

3.5.62    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.

3.5.63    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.

3.5.64    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.

3.5.65    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.

3.5.66    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. The ETs were reminded to update the BMP boundary in the Regular Marine Travel Route Plan.

3.5.67    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 9 March 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

810291.129

816678.735

1.135

S2

810958.272

815831.531

0.864

810958.294

815831.517

1.007

S3

810716.585

815953.308

1.341

810716.586

815953.341

1.487

S4

811221.433

816151.381

0.931

811221.528

816151.433

1.176

 

Table 3.10       Comparison of Measurement  

Comparison of measurement

Remarks and Recommendation

Monitoring Station

Easting
(m)

Northing (m)

Surface Level
(mPD)

S1

-0.031

0.008

0.185

Level continuously increased

S2

0.022

-0.014

0.143

Level continuously increased

S3

0.001

0.033

0.146

Level continuously increased

S4

0.095

0.052

0.245

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 March 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)

2-Mar-16

9.68

3.50

5.35

8.85

3.65

4.75

4-Mar-16

10.06

2.15

3.50

11.10

2.00

3.20

7-Mar-16

11.39

2.85

6.00

11.64

5.30

16.60

9-Mar-16

9.45

5.90

9.60

9.90

4.00

9.85

11-Mar-16

8.91

4.35

6.45

8.53

3.55

3.70

14-Mar-16

8.60

3.10

7.80

8.73

2.75

6.70

16-Mar-16

8.17

2.45

4.80

8.23

2.45

4.75

18-Mar-16

8.12

2.65

4.40

7.92

3.25

4.95

21-Mar-16

7.88

4.35

6.65

7.99

12.10

16.95

23-Mar-16

7.73

5.55

6.45

7.58

7.00

9.00

25-Mar-16

7.35

3.75

4.95

7.33

3.95

8.30

28-Mar-16

8.28

4.55

7.40

7.79

3.75

5.65

30-Mar-16

8.48

5.00

3.90

8.31

4.25

4.40

Average

8.77

3.86

5.94

8.76

4.46

7.60


 

Mudflat Ecology Monitoring

Sampling Zone

3.6.6       In order to collect baseline information of mudflats in the study site, the study site was divided into three sampling zones (labeled as TC1, TC2, TC3) in Tung Chung Bay and one zone in San Tau (labeled as ST) (Figure 2.1 of Appendix O). The horizontal length of sampling zones TC1, TC2, TC3 and ST were about 250 m, 300 m, 300 m and 250 m, respectively. Survey of horseshoe crabs, seagrass beds and intertidal communities were conducted in every sampling zone. The present survey was conducted in March 2016 (totally 6 sampling days between 8th to 26th March 2016).

Horseshoe Crabs

3.6.7       Active search method was conducted for horseshoe crab monitoring by two experienced surveyors at every sampling zone. During the search period, any accessible and potential area would be investigated for any horseshoe crab individuals within 2-3 hours in low tide period (tidal level below 1.2 m above Chart Datum (C.D.)). Once a horseshoe crab individual was found, the species was identified referencing to Li (2008). The prosomal width, inhabiting substratum and respective GPS coordinate were recorded. A photographic record was taken for future investigation. Any grouping behavior of individuals, if found, was recorded. The horseshoe crab surveys were conducted on 8th (for TC3), 13th (for TC1), 20th (for TC2), 22nd (for ST) and 26th (second survey for TC1) March 2016. The weather was generally cloudy for all day time surveys (13th-26th Mar) while it was humid during the night time survey (8th Mar). Since there was intermittent rain during the survey for TC1 on 13th Mar, the horseshoe crab trail would cease that searching became difficult. Hence a second survey was conducted on 26th Mar under cloudy weather.

Seagrass Beds

Active search method was conducted for seagrass bed monitoring by two experienced surveyors at every sampling zone. During the search period, any accessible and potential area would be investigated for any seagrass beds within 2-3 hours in low tide period. Once seagrass bed was found, the species, estimated area, estimated coverage percentage and respective GPS coordinate were recorded. A photographic record was taken for future investigation. The seagrass beds surveys were conducted on 8th (for TC3), 13th (for TC1), 20th (for TC2) and 22nd (for ST) March 2016. The weather was cloudy and cold for all day time surveys (13th-22nd Mar) while it was humid during the night time survey (8th Mar).

Intertidal Soft Shore Communities

3.6.8       The intertidal soft shore community surveys were conducted in low tide period 8th (for TC3), 12th (for ST), 13th (for TC1) and 20th (for TC2) March 2016. At each sampling zone, three 100 m horizontal transects were laid at high tidal level (H: 2.0 m above C.D.), mid tidal level (M: 1.5 m above C.D.) and low tidal level (L: 1.0 m above C.D.). Along every horizontal transect, ten random quadrats (0.5 m x 0.5m) were placed.

3.6.9       Inside a quadrat, any visible epifauna were collected and were in-situ identified to the lowest practical taxonomical resolution. Whenever possible a hand core sample (10 cm internal diameter ´ 20 cm depth) of sediments was collected in the quadrat. The core sample was gently washed through a sieve of mesh size 2.0 mm in-situ. Any visible infauna were collected and identified. Finally the top 5 cm surface sediments were dug for visible infauna in the quadrat regardless of hand core sample was taken.

3.6.10    All collected fauna were released after recording except some tiny individuals that are too small to be identified on site. These tiny individuals were taken to laboratory for identification under dissecting microscope.

3.6.11    The taxonomic classification was conducted in accordance to the following references: Polychaetes: Fauchald (1977), Yang and Sun (1988); Arthropods: Dai and Yang (1991), Dong (1991); Mollusks: Chan and Caley (2003), Qi (2004).

Data Analysis

3.6.12    Data collected from direct search and core sampling was pooled in every quadrat for data analysis. Shannon-Weaver Diversity Index (H¡¦) and Pielou¡¦s Species Evenness (J) were calculated for every quadrat using the formulae below,

H¡¦= -£U ( Ni / N ) ln ( Ni / N ) (Shannon and Weaver, 1963)

J = H¡¦ / ln S, (Pielou, 1966)

 

where S is the total number of species in the sample, N is the total number of individuals, and Ni is the number of individuals of the ith species.

Mudflat Ecology Monitoring Results and Conclusion

Horseshoe Crabs

3.6.13    In general, two species of horseshoe crab Carcinoscorpius rotundicauda (total 23 ind.) and Tachypleus tridentatus (total 17 ind.) were recorded. For one sight record, grouping of 2-8 individuals was observed at same locations with similar substratum (fine sand or soft mud). Photo records were shown in Figure 3.1 of Appendix O while the complete records of horseshoe crab survey in every sampling zone were shown in Annex II of Appendix O.

3.6.14    Table 3.1 of Appendix O summarizes the survey results of horseshoe crab in present survey. For Carcinoscorpius rotundicauda,there were 21 and 2 individuals in TC3 and ST respectively. For TC3, the search record was 3.5 ind. hr-1 person-1 while the average body size was 35.49 mm (prosomal width ranged 25.53-48.12 mm). For ST, the search record was 0.3 ind. hr-1 person-1 while the average body size was 35.70 mm (prosomal width ranged 16.82-54.58 mm). No individual was found in TC1 and TC2.

3.6.15    For Tachypleus tridentatus, there was 17 individuals recorded in TC3 only. The search record was 2.8 ind. hr-1 person-1 while the average body size was 41.83 mm (prosomal width ranged 26.79-48.91 mm).

3.6.16    In the previous survey of March 2015, there was one important finding that a mating pair of Carcinoscorpius rotundicauda was found in ST (prosomal width: male 155.1 mm, female 138.2 mm) (Figure 3.2 of Appendix O). It indicated the importance of ST as a breeding ground of horseshoe crab. Moreover, two moults of Carcinoscorpius rotundicauda were found in TC1 with similar prosomal width 130-140 mm (Figure 3.2 of Appendix O). It reflected that a certain numbers of moderately sized individuals inhabited the sub-tidal habitat of Tung Chung Wan after its nursery period on soft shore. These individuals might move onto soft shore during high tide for feeding, moulting and breeding. Then it would return to sub-tidal habitat during low tide. Because the mating pair should be inhabiting sub-tidal habitat in most of the time. The record was excluded from the data analysis to avoid mixing up with juvenile population living on soft shore. In present survey the records of the two big individuals of Carcinoscorpius rotundicauda (prosomal width 117.37 mm and 178.17 mm) were excluded from data analysis according to the same principle.

3.6.17    No marked individual of horseshoe crab was recorded in present survey. Some marked individuals were found in previous surveys conducted in September 2013, March 2014 and September 2014. All of them were released through a conservation programme conducted by Prof. Paul Shin (Department of Biology and Chemistry, The City University of Hong Kong (CityU)). It was a re-introduction trial of artificial bred horseshoe crab juvenile at selected sites. So that the horseshoe crabs population might be restored in the natural habitat. Through a personal conversation with Prof. Shin, about 100 individuals were released in the sampling zone ST on 20 June 2013. All of them were marked with color tape and internal chip detected by specific chip sensor. There should be second round of release between June and September 2014 since new marked individuals were found in the survey of September 2014.

3.6.18    The artificial bred individuals, if found, would be excluded from the results of present monitoring programme in order to reflect the changes of natural population. However, the mark on their prosoma might have been detached during moulting after a certain period of release. The artificially released individuals were no longer distinguishable from the natural population without the specific chip sensor. The survey data collected would possibly cover both natural population and artificially bred individuals.

 

Population difference among the sampling zones

3.6.19    Figures 3.3 and 3.4 of Appendix O show the changes of number of individuals, mean prosomal width and search record of horseshoe crabs Carcinoscorpius rotundicauda and Tachypleus tridentatus respectively in every sampling zone along the sampling months. In general, higher search records (i.e. number of individuals) of both species were always found in ST followed by TC3 from September 2012 to June 2014. Then the search record in TC3 was even higher than that in ST from September 2014 to June 2015. In September 2015, the search records were similar in TC3 and ST. In March 2016 (present survey), higher search record was noticed in TC3 again. For TC1, the search record was at low to medium level and the number of both species could fluctuate along the sampling months. Relatively, search record was very low in TC2 (2 ind. in Sep. 2013, 1 ind. in Mar., Jun., Sep. 2014, Mar. and Jun 2015, 4 ind. in Sep. 2015). For the body size, larger individuals of Carcinoscorpius rotundicauda were usually found in ST and TC1 relative to those in TC3. For Tachypleus tridentatus, larger individuals were also found in ST followed by TC3 and TC1.

3.6.20    Throughout the monitoring period conducted, it was obvious that TC3 and ST (western shore of Tung Chung Wan) was an important nursery ground for horseshoe crab especially newly hatched individuals due to larger area of suitable substratum (fine sand or soft mud) and less human disturbance (far from urban district). Relatively, other sampling zones were not a suitable nursery ground especially TC2. Possible factors were less area of suitable substratum (especially TC1) and higher human disturbance (TC1 and TC2: close to urban district and easily accessible). In TC2, large daily salinity fluctuation was a possible factor either since it was flushed by two rivers under tidal inundation. The individuals inhabiting TC1 and TC2 were confined in small moving range due to limited area of suitable substrata during the nursery period.

Seasonal variation of horseshoe crab population

3.6.21    Throughout the monitoring period conducted, the search record of horseshoe crab declined obviously during dry season especially December (Figures 3.3 and 3.4 of Appendix O). In December 2013, no individual of horseshoe crab was found. In December 2014, 2 individuals of Carcinoscorpius rotundicauda and 8 individuals of Tachypleus tridentatus were found only.  In December 2015, 2 individuals of Carcinoscorpius rotundicauda, 6 individuals of Tachypleus tridentatus and one newly hatched, unidentified individual were found only. The horseshoe crabs were inactive and burrowed in the sediments during cold weather (<15 ºC). Similar results of low search record in dry season were reported in a previous territory-wide survey of horseshoe crab. For example, the search records in Tung Chung Wan were 0.17 ind. hr-1 person-1 and 0.00 ind. hr-1 person-1 in wet season and dry season respectively (details see Li, 2008). After the dry season, the search record increased with the warmer climate.

3.6.22    Between the sampling months September 2012 and December 2013, Carcinoscorpius rotundicauda was a less common species relative to Tachypleus tridentatus. Only 4 individuals were ever recorded in ST in December 2012. This species had ever been believed of very low density in ST hence the encounter rate was very low. Since March. 2014, it was found in all sampling zones with higher abundance in ST. Based on its average size (mean prosomal width 39.28-49.81 mm), it indicated that breeding and spawning of this species had occurred about 3 years ago along the coastline of Tung Chun Wan. However, these individuals were still small while their walking trails were inconspicuous. Hence there was no search record in previous sampling months. From March 2014 to September 2015, more individuals were recorded due to larger size and higher activity (i.e. more conspicuous walking trail).

3.6.23    For Tachypleus tridentatus, sharp increase of number of individuals was recorded in ST with wet season (from March to September 2013). According to a personal conversation with Prof. Shin (CityU), his monitoring team had recorded similar increase of horseshoe crab population during wet season. It was believed that the suitable ambient temperature increased its conspicuousness. However similar pattern was not recorded during the wet season of 2014. The number of individuals increased in March and June 2014 followed by a rapid decline in September 2014. Then the number of individuals fluctuated in TC3 while it decreased steadily in ST until September. 2015. Apart from natural mortality, migration from nursery soft shore to subtidal habitat was another possible cause. Since the mean prosomal width of Tachypleus tridentatus continued to grow and reached about 50 mm since March 2014. Then it varied slightly between 50-65 mm from September 2014 to September 2015. Most of the individuals might have reached a suitable size strong enough to forage in sub-tidal habitat.

3.6.24    Since TC3 and ST were regarded as important nursery ground for horseshoe crab, box plots of prosomal width of two horseshoe crab species were constructed to investigate the changes of population in details.

Box plot of horseshoe crab populations in TC3

3.6.25    Figure 3.5 of Appendix O shows the changes of prosomal width of Carcinoscorpius rotundicauda and Tachypleus tridentatus in TC3. As mentioned above, Carcinoscorpius rotundicauda was rarely found between September 2012 and December 2013 hence the data were lacking. In March 2014, the major size (50% of individual records between upper and lower quartile) ranged 40-60 mm while only few individuals were found. From March 2014 to September 2015, the size of major population decreased and more small individuals were recorded after March of every year. It indicated new rounds of successful breeding and spawning of Carcinoscorpius rotundicauda in TC3. It matched with the previous mating record in ST in March 2015.

3.6.26    For Tachypleus tridentatus, the major size ranged 20-50 mm while the number of individuals found fluctuated from September 2012 to June 2014. Then a slight but consistent growing trend was observed. The prosomal width increased from 25-35 mm in September 2014 to 35-65 mm in June 2015. As mentioned, the large individuals might have reached a suitable size for migrating from the nursery soft shore to subtidal habitat. It accounted for the declined population in TC3.

3.6.27    From June 2015 to March 2016 (present survey), slight increasing trends of major size were noticed for both species. It might be accounted by new round of spawning. But it was yet to conclude until wet season results (June & September 2016) were available.

Box plot of horseshoe crab populations in ST

3.6.28    Figure 3.6 of Appendix O shows the changes of prosomal width of Carcinoscorpius rotundicauda and Tachypleus tridentatus in ST. As mentioned above, Carcinoscorpius rotundicauda was rarely found between September 2012 and December 2013 hence the data were lacking. From Mar. 2014 to Sep. 2015, the size of major population decreased and more small individuals were recorded after June of every year. It indicated new rounds of successful breeding and spawning of Carcinoscorpius rotundicauda in ST. It matched with the previous mating record in ST in March 2015. Because most of newly hatched individuals (prosomal width ~5mm) would take about half year to grow to a size with conspicuous walking trail.

3.6.29    For Tachypleus tridentatus, a consistent growing trend was observed for the major population from December 2012 to December 2014 regardless of change of search record. The prosomal width increased from 15-30 mm to 55-70 mm. As mentioned, the large individuals might have reached a suitable size for migrating from the nursery soft shore to subtidal habitat. From March to September 2015, the size of major population decreased slightly to a prosomal width 40-60 mm. At the same time, the number of individuals decreased gradually. It further indicated some of large individuals might have migrated to sub-tidal habitats. In December 2015, two big individuals (prosomal width 89.27 mm and 98.89 mm) were recorded only while it could not represent the major population.

3.6.30    From December 2015 to March 2016 (present survey), the number of horseshoe crab recorded was very few in ST. Hence the population change of both species could not be determined.

3.6.31    As a summary for horseshoe crab populations in TC3 and ST, there was successful spawning of Carcinoscorpius rotundicauda from 2014 to 2015 while the spawning time should be in spring. There were consistent, increasing trends of population size in these two sampling zones. For Tachypleus tridentatus, small individuals were rarely found TC3 and ST from 2014 to 2015. It was believed no occurrence of successful spawning. The existing individuals (that recorded since 2012) grew to a mature size and migrated to sub-tidal habitat. Hence the number of individuals decreased gradually. It was expected the population would remain at low level until new round of successful spawning.

Impact of the HKLR project

3.6.32    The present survey was the 14th survey of the EM&A programme during the construction period. Based on the results, impact of the HKLR project could not be detected on horseshoe crabs considering the factor of natural, seasonal variation. In case, abnormal phenomenon (e.g. very few numbers of horseshoe crab individuals in wet season, large number of dead individuals on the shore) is observed, it would be reported as soon as possible.

Seagrass Beds

3.6.33    In general, seagrass was found in ST only. Two seagrass species Halophila ovalis and Zostera japonica were recorded. Both species were found on sandy substratum nearby the seaward side of mangrove vegetation at 2.0 m above C.D. The seagrass bed existed in irregular patches or long strand in various sizes. For one long strand, two seagrass species were found coexisting in variable coverage. Photo records were shown in Figure 3.7 of Appendix O while the complete records of seagrass beds survey were shown in Annex III of Appendix O.

3.6.34    Table 3.2 of Appendix O summarize the results of seagrass beds survey in ST. Eight patches of Halophila ovalis were found while the total seagrass bed area was about 230.6 m2 (average area 28.8 m2). The largest patch was a horizontal strand with seagrass bed area 100.4 m2. It coexisted with another seagrass species and remained at very low coverage (10%). Other three horizontal strands were at medium size (15.8-41.1 m2) and high coverage (80-100%). The rest were small patches (1.5-17.3 m2) and variable coverage (20-90%). For Zostera japonica, it was mainly found coexisting with Halophila ovalis in the largest strand (100.4 m2) of seagrass bed with high coverage 90%.

3.6.35    Since majority of seagrass bed was confined in ST, the temporal change of both seagrass species were investigated in details.

Temporal variation of seagrass beds

3.6.36    Figure 3.8 of Appendix O shows the changes of estimated total area of seagrass beds in ST along the sampling months. For Zostera japonica, it was not recorded in the 1st and 2nd surveys of monitoring programme. Seasonal recruitment of few, small patches (total seagrass area: 10 m2) was found in March 2013 that grew within the large patch of seagrass Halophila ovalis. Then the patch size increased and merged gradually with the warmer climate from March to June 2013 (15 m2). However the patch size decreased sharply and remained similar from September 2013 (4 m2) to March 2014 (3 m2). In June 2014, the patch size increased obviously again (41 m2) with warmer climate. Similar to previous year, the patch size decreased again and remained similar September 2014 (2 m2) to December 2014 (5 m2). From March to June 2015, the patch size increased sharply again (90.0 m2). It might be due to the disappearance of the originally dominant seagrass Halophila ovalis resulting in less competition for substratum and nutrients. From September 2015 to March 2016, it was found coexisting with seagrass Halophila ovalis with steady increasing patch size and variable coverage.

3.6.37    For Halophila ovalis, it was recorded as 3-4 medium to large patches (area 18.9 - 251.7 m2; vegetation coverage 50-80%) beside the mangrove vegetation at tidal level 2 m above C.D in September 2012 (first survey). The total seagrass bed area grew steadily from 332.3 m2 in September 2012 to 727.4 m2 in December 2013. Flowers could be observed in the largest patch during its flowering period in December 2013. In March 2014, 31 small to medium patches were newly recorded (variable area 1-72 m2 per patch, vegetation coverage 40-80% per patch) in lower tidal zone between 1.0 and 1.5 m above C.D. The total seagrass area increased further to 1350 m2. In June 2014, these small and medium patches grew and extended to each others. These patches were no longer distinguishable and were covering a significant mudflat area of ST. It was generally grouped into 4 large areas (1116 ¡V 2443 m2) of seagrass beds characterized of patchy distribution, variable vegetable coverage (40-80%) and smaller leaves. The total seagrass bed area increased sharply to 7629 m2. In September 2014, the total seagrass area declined sharply to 1111 m2. There were only 3-4 small to large patches (6 - 253 m2) at high tidal level and 1 patch at low tidal level (786 m2). Typhoon or strong water current was a possible cause (Fong, 1998). In September 2014, there were two tropical cyclone records in Hong Kong (7th-8th September: no cyclone name, maximum signal number 1; 14th-17th September: Kalmaegi maximum signal number 8SE) before the seagrass survey dated 21st September 2014. The strong water current caused by the cyclone, Kalmaegi especially, might have given damage to the seagrass beds. In addition, natural heat stress and grazing force were other possible causes reducing seagrass beds area. Besides, Halophila ovalis could be found in other mud flat area surrounding the single patch. But it was hardly distinguished into patches due to very low coverage (10-20%) and small leaves.

3.6.38    In December 2014, all the seagrass patches of Halophila ovalis disappeared in ST. Figure 3.9 of Appendix O shows the difference of the original seagrass beds area nearby the mangrove vegetation at high tidal level between June 2014 and December 2014. Such rapid loss would not be seasonal phenomenon because the seagrass beds at higher tidal level (2.0 m above C.D.) were present and normal in December 2012 and 2013. According to Fong (1998), similar incident had occurred in ST in the past. The original seagrass area had declined significantly during the commencement of the construction and reclamation works for the international airport at Chek Lap Kok in 1992. The seagrass almost disappeared in 1995 and recovered gradually after the completion of reclamation works. Moreover, incident of rapid loss of seagrass area was also recorded in another intertidal mudflat in Lai Chi Wo in 1998 with unknown reason. Hence Halophila ovalis was regarded as a short-lived and r-strategy seagrass that can colonize areas in short period but disappears quickly under unfavourable conditions (Fong, 1998).

Unfavourable conditions to seagrass Halophila ovalis

3.6.39    Typhoon or strong water current was suggested as one unfavourable condition to Halophila ovalis (Fong, 1998). As mentioned above, there were two tropical cyclone records in Hong Kong in September 2014. The strong water current caused by the cyclones might have given damage to the seagrass beds.

3.6.40    Prolonged light deprivation due to turbid water would be another unfavouable condition. Previous studies reported that Halophila ovalis had little tolerance to light deprivation. During experimental darkness, seagrass biomass declined rapidly after 3-6 days and seagrass died completely after 30 days. The rapid death might be due to shortage of available carbohydrate under limited photosynthesis or accumulation of phytotoxic end products of anaerobic respiration (details see Longstaff et al., 1999). Hence the seagrass bed of this species was susceptible to temporary light deprivation events such as flooding river runoff (Longstaff and Dennison, 1999).

3.6.41    In order to investigate any deterioration of water quality (e.g. more turbid) in ST, the water quality measurement results at two closest monitoring stations SR3 and IS5 of the EM&A programme were obtained from the water quality monitoring team. Based on the results from June to December 2014, the overall water quality was in normal fluctuation except there was one exceedance of suspended solids (SS) at both stations in September. On 10th September, 2014, the SS concentrations measured at mid-ebb tide at stations SR3 (27.5 mg/L) and IS5 (34.5 mg/L) exceeded the Action Level (≤23.5 mg/L and 120% of upstream control station¡¦s reading) and Limit Level (≤34.4 mg/L and 130% of upstream control station¡¦s reading) respectively. The turbidity readings at SR3 and IS5 reached 24.8-25.3 NTU and 22.3-22.5 NTU respectively. The temporary turbid water should not be caused by the runoff from upstream rivers. Because there was no rain or slight rain from 1st to 10th September 2014 (daily total rainfall at the Hong Kong International Airport: 0-2.1 mm; extracted from the climatological data of Hong Kong Observatory). The effect of upstream runoff on water quality should be neglectable in that period. Moreover the exceedance of water quality was considered unlikely to be related to the contract works of HKLR according to the ¡¥Notifications of Environmental Quality Limits Exceedances¡¦ provided by the respective environmental team. The respective construction of seawall and stone column works, which possibly caused turbid water, were carried out within silt curtain as recommended in the EIA report. Moreover there was no leakage of turbid water, abnormity or malpractice recorded during water sampling. In general, the exceedance of suspended solids concentration was considered to be attributed to other external factors, rather than the contract works.

3.6.42    Based on the weather condition and water quality results in ST, the co-occurrence of cyclone hit and turbid waters in September 2014 might have combined the adverse effects on Halophila ovalis that leaded to disappearance of this short-lived and r-strategy seagrass species. Fortunately Halophila ovalis was a fast-growing species (Vermaat et al., 1995). Previous studies showed that the seagrass bed could be recovered to the original sizes in 2 months through vegetative propagation after experimental clearance (Supanwanid, 1996). Moreover it was reported to recover rapidly in less than 20 days after dugong herbivory (Nakaoka and Aioi, 1999). As mentioned, the disappeared seagrass in ST in 1995 could recover gradually after the completion of reclamation works for international airport (Fong, 1998). The seagrass beds of Halophila ovalis might recolonize the mudflat of ST through seed reproduction as long as there was no unfavourable condition in the coming months.

Recolonization of seagrass beds

3.6.43    Figure 3.9 of Appendix O shows the changes of seagrass bed area at ST. From March to June 2015, 2-3 small patches of Halophila ovalis were newly found coinhabiting with another seagrass species Zostera japonica. But its total patch area was still very low relative to the previous records. The recolonization rate was low while cold weather and insufficient sunlight were possible factors between December 2014 and March 2015. Moreover, it would need to compete with more abundant seagrass Zostera japonica for substratum and nutrient. Since Zostera japonica had extended and had covered the original seagrass bed of Halophila ovalis at certain degree. From June to March 2016, the total seagrass area of Halophila ovalis had increased rapidly from 6.8 m2 to 230.63 m2. It had recolonized its original patch locations and covered Zostera japonica. Hence it was expected that the seagrass bed of Halophila ovalis would increase continually in the following months.

Impact of the HKLR project

3.6.44    The present survey was the 14th survey of the EM&A programme during the construction period. According to the results of present survey, there was recolonization of both seagrass species Halophila ovalis and Zostera japonica in ST. The seagrass patches were believed in recovery. Hence the negative impact of HKLR project on the seagrass was not significant. In case, adverse phenomenon (e.g. reduction of seagrass patch size, abnormal change of leave colour) is observed again, it would be reported as soon as possible.


 

Intertidal Soft Shore Communities

3.6.45    Table 3.3 and Figure 3.10 of Appendix O show the types of substratum along the horizontal transect at every tidal level in every sampling zone. The relative distribution of different substrata was estimated by categorizing the substratum types (Gravels & Boulders / Sands / Soft mud) of the ten random quadrats along the horizontal transect. The distribution of substratum types varied among tidal levels and sampling zones:

¡P       In TC1, high percentage of ¡¥Gravels and Boulders¡¦ (80-90%) was recorded at high and mid tidal levels. ¡¥Gravels and Boulders¡¦ (60%) and ¡¥Sands¡¦ (30%) were the major substratum types at low tidal level.

¡P       In TC2, high percentage of ¡¥Soft mud¡¦ (80%) was recorded at all tidal levels.

¡P       In TC3, the substratum type was clearly different between high-mid tidal level and low tidal level. ¡¥Sands¡¦ (50-60%) and ¡¥Soft mud¡¦ (40-50%) were the major substratum types at high and mid tidal levels. High percentage of ¡¥Gravels and Boulders¡¦ (90%) was recorded at low tidal level.

¡P        In ST, the substratum type was clearly different between high-mid tidal level and low tidal level. ¡¥Gravels and Boulders¡¦ (100%) was the only substratum type at high and mid tidal levels. At low tidal level, higher percentage of ¡¥Soft mud¡¦ (80%) was recorded followed by ¡¥Gravels and Boulders¡¦ (20%).There was neither consistent vertical nor horizontal zonation pattern of substratum type in all sampling zones. Such heterogeneous variation should be caused by different hydrology (e.g. wave in different direction and intensity) received by the four sampling zones.

3.6.46    There was neither consistent vertical nor horizontal zonation pattern of substratum type in all sampling zones. Such heterogeneous variation should be caused by different hydrology (e.g. wave in different direction and intensity) received by the four sampling zones.

3.6.47    Table 3.4 of Appendix O lists the total abundance, density and number of taxon of every phylum in this survey. A total of 11728 individuals were recorded. Mollusca was significantly the most abundant phylum (total individuals 11496, density 383 ind. m-2, relative abundance 98.0%). The second abundant phylum was Arthropoda (127 ind., 4 ind. m-2, 1.1%). The less abundant phyla were Annelida (62 ind., 2 ind. m-2, 0.5%) and Cnidaria (17 ind., 1 ind. m-2, 0.1%). Relatively other phyla were very low in abundances (density £1 ind. m-2, relative abundance £0.1%). Moreover, the most diverse phylum was Mollusca (37 taxa) followed by Arthropoda (11 taxa) and Annelida (10 taxa). There was 1 taxon recorded only for other phyla. The taxonomic resolution and complete list of collected specimens are shown in Annex IV and V of Appendix O.

3.6.48    Table 3.5 of Appendix O shows the number of individual, relative abundance and density of each phylum in every sampling zone. The total abundance (2313-4085 ind.) varied among the four sampling zones while the phyla distributions were similar. In general, Mollusca was the most dominant phylum (no. of individuals: 2213-4054 ind.; relative abundance 95.7-99.2%; density 295-541 ind. m-2). Other phyla were significantly lower in number of individuals. Arthropoda was the second abundant phylum (15-68 ind.; 0.4-2.9%; 2-9 ind. m-2). Annelida was the third abundant phylum in TC1, TC2 and TC3 (7-26 ind.; 0.2-1.1%; 1-3 ind. m-2) while it was the fourth abundant in ST (8 ind.; 0.3%; 1 ind. m-2). Cnidaria (sea anemone) was the third abundant phylum (15 ind.; 0.6%; 2 ind. m-2) in ST. Relatively other phyla were low in abundance in all sampling zones (≤ 0.1%)

Dominant species in every sampling zone

3.6.49    Table 3.6 of Appendix O lists the abundant species (relative abundance >10%) in every sampling zone. In TC1, gastropod Batillaria multiformis was the most abundant species of very high density (620 ind. m-2, relative abundance 84%) at high tidal level (major substratum: ¡¥Gravels and Boulders¡¦). At mid tidal level (major substratum: ¡¥Gravels and Boulders¡¦), gastropod Batillaria multiformis was also the most abundant species of high density (214 ind. m-2, relative abundance 47%) followed by gastropod Monodonta labio (81 ind. m-2, 18%) and rock oyster Saccostrea cucullata (70 ind. m-2, 16%, attached on boulders) at moderate densities. At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata was the most abundant species of moderate-high density (141 ind. m-2, 32%) followed by gastropods Monodonta labio (98 ind. m-2, 22%), Batillaria zonalis (51 ind. m-2, 11%) and Batillaria multiformis (47 ind. m-2, 10%) at moderate densities.

3.6.50    At TC2, gastropod Cerithidea djadjariensis (123 ind. m-2, 32%) was the most abundant at moderate density followed by gastropods Batillaria multiformis (69 ind. m-2, 18%)  Cerithidea cingulata (41 ind. m-2, 11%) and rock oyster Saccostrea cucullata (67 ind. m-2, 17%) at high tidal level (major substratum: ¡¥Soft mud¡¦). At mid and low tidal levels (major substrata: ¡¥Soft mud¡¦), rock oyster Saccostrea cucullata (102-103 ind. m-2, 32-45%) was the most abundant followed by gastropod Batillaria zonalis (48-95 ind. m-2, 22-30%). Besides, gastropod Cerithidea djadjariensis (34 ind. m-2, 11%) was the third abundant at mid tidal level.

3.6.51    At TC3, the abundant species were quite different between three tidal levels. At high tidal level (major substratum: ¡¥Sands¡¦), gastropod Batillaria multiformis was the most abundant species of high density (268 ind. m-2, 59%) followed by gastropod Cerithidea djadjariensis (123 ind. m-2, 27%). At mid tidal level (major substratum: ¡¥Sands¡¦), the abundant species were at moderate densities including gastropods Cerithidea djadjariensis (86 ind. m-2, 32%), Cerithidea cingulata (55 ind. m-2, 21%), Batillaria multiformis (51 ind. m-2, 19%) and Batillaria zonalis (46 ind. m-2, 17%). At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), the abundant species were at moderate densities including rock oyster Saccostrea cucullata (143 ind. m-2, 31%), gastropods Monodonta labio (127 ind. m-2, 27%) and Batillaria multiformis (125 ind. m-2, 27%).

3.6.52    At ST, gastropod gastropods Monodonta labio (166 ind. m-2, 42%) and Batillaria multiformis (120 ind. m-2, 31%) were of moderate densities followed by rock oyster Saccostrea cucullata (48 ind. m-2, 12%) at high tidal level (major substratum: ¡¥Gravels and Boulders¡¦). At mid tidal level (major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata (176 ind. m-2, 39%) and gastropod Monodonta labio (120 ind. m-2, 26%) became abundant followed by gastropod Lunella coronata (61 ind. m-2, 13%). At low tidal level (major substratum: ¡¥Soft mud¡¦), rock oyster Saccostrea cucullata (34 ind. m-2, 38%) and gastropod Lunella coronata (19 ind. m-2, 21%) were at low densities.

3.6.53    In general, there was no consistent zonation pattern of species distribution observed across all sampling zones and tidal levels. The species distribution should be determined by the type of substratum primarily. In general, gastropods Batillaria multiformis (total number of individuals: 3864 ind., relative abundance 32.9%), Cerithidea djadjariensis (1103 ind., 9.4%) and Batillaria zonalis (713 ind., 6.1%) were the most commonly occurring species on sandy and soft mud substrata. Rock oyster Saccostrea cucullata (2263 ind., 19.3%), gastropods Monodonta labio (1706 ind., 14.5%) were commonly occurring species inhabiting gravel and boulders substratum.

Biodiversity and abundance of soft shore communities

3.6.54    Table 3.7 of Appendix O shows the mean values of species number, density, biodiversity index H¡¦ and species evenness J of soft shore communities at every tidal level and in every sampling zone. Among the sampling zones, there was no clear difference on mean species number (7-9 spp. 0.25 m-2), mean H¡¦ (1.2-1.5) and mean J (0.5-0.7). The mean density of TC1 (545 ind. m-2) was higher than other sampling zones (308-398 ind. m-2).

3.6.55    Across the tidal levels, there was no consistent difference of the mean number of species, H¡¦ and J in all sampling zones. For the mean density, a general decreasing trend was observed from high to low tidal level at TC1, TC2 and ST. As mentioned, the variation of mean density should be determined by the type of substratum primarily.

3.6.56    Figures 3.11 to 3.14 of Appendix O show the temporal changes of mean number of species, mean density, H¡¦ and J at every tidal level and in every sampling zone along the sampling months. Overall no consistent temporal change of any biological parameters was observed. All the parameters were under slight and natural fluctuation with the seasonal variation.

Impact of the HKLR project

3.6.57    The present survey was the 14th survey of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project were not detected on intertidal soft shore community. In case, abnormal phenomenon (e.g. large reduction of fauna densities and species number) is observed, it would be reported as soon as possible. 

3.7                Solid and Liquid Waste Management Status

3.7.1       The Contractor registered with EPD as a Chemical Waste Producer on 12 July 2012 for the Contract. Sufficient numbers of receptacles were available for general refuse collection and sorting.

3.7.2       The summary of waste flow table is detailed in Appendix K.

3.7.3       The Contractor was reminded that chemical waste containers should be properly treated and stored temporarily in designated chemical waste storage area on site in accordance with the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes.

3.8                Environmental Licenses and Permits

3.8.1       The valid environmental licenses and permits during the reporting period are summarized in Appendix L.

 

 


4        Environmental Complaint and Non-compliance

4.1.1       The detailed air quality, noise, water quality and dolphin exceedances are provided in Appendix M. Also, the summaries of the environmental exceedances are presented as follows:

Air Quality

4.1.2      There were no Action and Limit Level exceedances of 1-hr TSP and 24-hour TSP were recorded at AMS5 and AMS6 during the reporting period.

Noise  

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

Water Quality

4.1.4       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.

Dolphin

4.1.5       There was one Limit Level exceedance of dolphin monitoring for the quarterly monitoring data (between March 2016 ¡V May 2016). According to the contractor¡¦s information, the marine activities undertaken for HKLR03 during the quarter of March 2016 ¡V May 2016 included removal of surcharge materials, temporary drainage diversion, ground investigation and maintenance of silt curtain.

4.1.6       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 Department¡¦s designated anchorage site ¡V Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

4.1.7       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 Department¡¦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.

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

4.2.1       There were no complaints received during the reporting period. The details of cumulative statistics of Environmental Complaints are provided in Appendix N.

4.2.2       No notification of summons and prosecution was received during the reporting period.

4.2.3       Statistics on notifications of summons and successful prosecutions are summarized in Appendix M.


 

5        Comments, Recommendations and Conclusion

5.1.1       According to the environmental site inspections undertaken during the reporting period, the following recommendations were provided:

¡P       The Contractor was reminded to cover stockpile of more than 20 bags of cement with impervious sheeting at N1 and A2 Bridge.

¡P       The Contractor was reminded to cover the stockpile of sand at A2 Bridge.

¡P       The Contractor was reminded to provide maintenance for the vessel to avoid dark smoke emission at S7.

¡P       The Contractor was reminded to provide water spraying for the rock breaking activity at S15.

¡P       The Contractor was reminded to utilize the dust screen of the drilling rig at S16.

¡P       The Contractor was reminded to remove the dusty materials at the road side of S25.

¡P       The Contractor was reminded to close the mechanical cover of the dump truck during transportation of fill materials at S25.

¡P       The Contractor was reminded to cover the stockpile of dusty fill material at N30.

¡P       The Contractor was reminded to align the silt curtain properly/ close the openings at Portion X.

¡P       The Contractor was reminded to fill in the gap for silt curtains at Portion X and HMA.

¡P       The Contractor was reminded to provide proper protection along seafront at S7 to avoid dropping of silt and debris into the sea.

¡P       The Contractor was reminded to pump out the water inside the concrete truck washing bay for proper wastewater treatment at S7.

¡P       The Contractor was reminded to replace the broken sand bags at S7.

¡P       The Contractor was reminded to repair the water pump of the automatic wheel wash system at S7.

¡P       The Contractor was reminded to rectify the wheel washing bay at S9.

¡P       The Contractor was reminded to indicate the source of discharge pipes on the pipes at S15.

¡P       The Contractor was reminded to maintain the wastewater treatment facility at S23 and properly treat all the wastewater before discharge.

¡P       The Contractor was reminded to provide sand bags along the site boundary next to the road in order prevent runoff onto the public roads at S25.

¡P       The Contractor was reminded to identify and mark the source of discharge pipe at the outlet at S25.

¡P       The Contractor was reminded to stop the leakage from the waste water treatment facility immediately at N26.

¡P       The Contractor was reminded to sign the checklist for checking wastewater treatment facilities after inspection immediately at N26.

¡P       The Contractor was reminded to place sand bags around the gully and provide an adequate wheel washing facility at N30.

¡P       The Contractor was reminded to provide proper protection along PR9 to avoid muddy runoff entering into the sea.

¡P       The Contractor was reminded to direct the discharge to the approved discharge point at PR10.

¡P       The Contractor was reminded to clean up the scum and block the abandon discharge pipe if it is not in use at PR10.

¡P       The Contractor was reminded to provide proper treatment for all wastewater generated from the site prior to discharge at PR10.

¡P       The Contractor was reminded to provide drip trays for chemicals at S7, S11, HMA, N1, N20, West Portal and Portion X.

¡P       The Contractor was reminded to remove/clean up the oil stain at N26 and S11.

¡P       The Contractor was reminded to provide proper labels for oil drums/ chemical containers at S11, N26 and West Portal.

¡P       The Contractor was reminded to remove the leakage and proper maintain the machinery at West Portal.

¡P       The Contractor was reminded to remove the accumulated waste at S8, S11, S15, S16, S23, S25, WA6, HMA, N1, N26 and West Portal.

¡P       The Contractor was reminded to remove the rubbish inside the rubbish bin regularly at WA6.

¡P       The Contractor was reminded to collect the empty chemical containers and disposal of through a licenced chemical waste collector at S8.

¡P       The Contractor was reminded to sort the filling materials before reclamation to reduce silty material content at S25.

¡P       The Contractor was reminded to remove the stagnant water at A2 Bridge, S7, S8, S11, S15, S23, S25, HMA PR9, West Portal and ventilation building to avoid mosquito breeding.

¡P       The Contractor was reminded to remove stagnant water inside the blocked U channel at N26.

¡P       The Contractor was reminded to level the road to avoid accumulation of water at S11.

¡P       The Contractor was reminded to fill the water pits to avoid accumulation of water at S11.

¡P       The Contractor was reminded to remove the stagnant water inside the H-beam at S8.

¡P       The Contractor was reminded to remove the materials from the trees at S9.

5.2               Recommendations

5.2.1       The impact monitoring programme for air quality, noise, water quality and dolphin ensured that any deterioration in environmental condition was readily detected and timely actions taken to rectify any non-compliance. Assessment and analysis of monitoring results collected demonstrated the environmental impacts of the contract. With implementation of the recommended environmental mitigation measures, the contract¡¦s environmental impacts were considered environmentally acceptable. The weekly environmental site inspections ensured that all the environmental mitigation measures recommended were effectively implemented.

5.2.2       The recommended environmental mitigation measures, as included in the EM&A programme, effectively minimize the potential environmental impacts from the contract. Also, the EM&A programme effectively monitored the environmental impacts from the construction activities and ensure the proper implementation of mitigation measures. No particular recommendation was advised for the improvement of the programme.

5.3.1         The construction phase and EM&A programme of the Contract commenced on 17 October 2012. This is the fifteenth Quarterly EM&A Report which summarizes the monitoring results and audit findings of the EM&A programme during the reporting period from 1 March 2016 to 31 May 2016.

Air Quality

5.3.2          There were no Action and Limit Level exceedances of 1-hr TSP and 24-hour TSP were recorded at AMS5 and AMS6 during the reporting period.

Noise

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

Water Quality

5.3.4          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.

Dolphin

5.3.5         There was a Limit Level exceedance of dolphin monitoring for the quarterly monitoring data (between March 2016 ¡V May 2016).

5.3.6         During this quarter of dolphin monitoring, no adverse impact from the activities of this construction project on Chinese White Dolphins was noticeable from general observations.

5.3.7         Although dolphins rarely occurred in the area of HKLR03 construction in the past and during the baseline monitoring period, it is apparent that dolphin usage has been significantly reduced in NEL since 2012, and many individuals have shifted away from the important habitat around the Brothers Islands.

5.3.8         It is critical to continuously monitor the dolphin usage in North Lantau region in the upcoming quarters, to determine whether the dolphins are continuously affected by the various construction activities in relation to the HZMB-related works, and whether suitable mitigation measure can be applied to revert the situation.

Mudflat -Sedimentation Rate

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

Mudflat - Ecology

5.3.10      The March 2016 survey was the fourteenth survey of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project could not be detected on horseshoe crabs, seagrass and intertidal soft shore community.

Environmental Site Inspection and Audit

5.3.11       Environmental site inspection was carried out on 3, 9, 16, 23 and 29 March 2016; 6, 14, 20 and 29 April 2016; and 4, 11, 18 and 27 May 2016. Recommendations on remedial actions were given to the Contractors for the deficiencies identified during the site inspections.

5.3.12      There were no complaints received in relation to the environmental impacts during the reporting period. 

5.3.13      No notification of summons and prosecution was received during the reporting period.


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