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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. 10 (Dec 2014 to Feb 2015)

 

22 June 2015

 

Revision 1

 

 

 

 

 

 

 

 

 

 

 

 

 

Main Contractor                                                                                                                     Designer

Atkins new logo
 

 


 


Contents

Executive Summary

1...... Introduction.. 1

1.1                          Basic Project Information. 1

1.2                          Project Organisation. 1

1.3                          Construction Programme. 1

1.4                          Construction Works Undertaken During the Reporting Period. 1

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

2.1                          Summary of EM&A Requirements. 3

2.2                          Action and Limit Levels. 4

2.3                          Event Action Plans. 5

2.4                          Mitigation Measures. 5

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

3.1                          Implementation of Environmental Measures. 6

3.2                          Air Quality Monitoring Results. 6

3.3                          Noise Monitoring Results. 7

3.4                          Water Quality Monitoring Results. 7

3.5                          Dolphin Monitoring Results. 7

3.6                          Mudflat Monitoring Results. 17

3.7                          Solid and Liquid Waste Management Status. 26

3.8                          Environmental Licenses and Permits. 26

4....... Environmental Complaint and Non-compliance. 27

4.1                          Environmental Exceedances. 27

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

5....... Comments, Recommendations and Conclusion.. 30

5.1                          Comments. 30

5.2                          Recommendations. 31

5.3                          Conclusions. 31

 

 

 

 

 

 

 

 

 

Figures

 

Figure 1.1         Location of the Site

Figure 2.1         Environmental Monitoring Stations    

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

 

                           

Appendices

 

Appendix A        Environmental Management Structure

Appendix B       Construction Programme

Appendix C       Location of Works Areas

Appendix D       Event and Action Plan  

Appendix E       Implementation Schedule of Environmental Mitigation Measures

Appendix F       Site Audit Findings and Corrective Actions

Appendix G       Air Quality Monitoring Data and Graphical Plots

Appendix H       Noise Monitoring Data and Graphical Plots

Appendix I         Water Quality Monitoring Data and Graphical Plots

Appendix J        Dolphin Monitoring Results

Appendix K       Waste Flow Table

Appendix L        Summary of Environmental Licenses and Permits

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

Appendix N       Cumulative Statistics on Complaints

Appendix O       Mudflat Monitoring Results


Executive Summary

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

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

China State Construction Engineering (Hong Kong) Ltd. was awarded by Highways Department as the Contractor to undertake the construction works of Contract No. HY/2011/03.  The main works of the Contract include land tunnel at Scenic Hill, tunnel underneath Airport Road and Airport Express Line, reclamation and tunnel to the east coast of the Airport Island, at-grade road connecting to the HKBCF and highway works of the HKBCF within the Airport Island and in the vicinity of the HKLR reclamation.  The Contract is part of the HKLR Project and HKBCF Project, these projects are considered to be ˇ§Designated Projectsˇ¨, under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap 499) and EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for the Project.  The current Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/H for HKBCF were issued on 22 December 2014 and 19 January 2015, 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 tenth Quarterly EM&A report for the Contract which summaries the monitoring results and audit findings of the EM&A programme during the reporting period from 1 December 2014 to 28 February 2015.

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

December 2014

January 2015

February 2015

Air Quality

1-hr TSP

1, 5, 11, 17, 23 and 29

2, 6, 12, 16, 22 and 28

3, 9, 13, 18 and 24

24-hr TSP

AMS5: 2, 5, 17, 22, 24 and 30

AMS6: 4, 10, 16, 22, 24 and 30

5, 9, 15, 21 and 27

2, 6, 12, 17, 23 and 27

Noise

1, 11, 17, 23 and 29

6, 16, 22 and 28

3, 9, 18 and 24

Water Quality

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

2, 5, 7, 9, 12, 14, 16, 19, 21, 23, 26, 28 and 30

2, 4, 6, 9, 11, 13, 16, 18, 20, 23, 25 and 27

Chinese White Dolphin

2, 9, 15 and 23

8, 15, 27 and 29

5, 13, 16 and 25

Mudflat Monitoring (Ecology)

6, 7, 10, 21, 22 and 23

-

-

Mudflat Monitoring (Sedimentation rate)

13

-

-

Site Inspection

3, 10, 17, 24 and 30

7, 14, 21 and 30

4, 11, 17 and 27

Due to malfunction of HVS at AMS5 on 28 November 2014, the 24-hr TSP monitoring undertaken at AMS5 was less than 24 hours and the result was therefore considered invalid. The 24-hr TSP monitoring was rescheduled from 28 November 2014 to 2 December 2014.  The monitoring result for 2 December 2014 is provided in this report.

Due to power interruption of HVS at station AMS5, the 24-hr TSP monitoring at station AMS5 was rescheduled from 4 December 2014 to 5 December 2014.

Due to malfunction of HVS at station AMS5, the 24-hr TSP monitoring at station AMS5 on 10 December 2014 was cancelled. The 24-hr TSP monitoring at station AMS5 was rescheduled to 17 December 2014 after repairing the HVS.

Due to the change of tide pattern and weather condition, mudflat monitoring (ecology) was rescheduled from 20 December 2014 to 10 December 2014.

Due to bad weather condition on 12 January 2015, the noise monitoring at station NMS5 was rescheduled from 12 January 2015 to 16 January 2015.

Due to boat availability issue, the dolphins monitoring was rescheduled from 3 December 2014 to 2 December 2014, 22 December 2014 to 23 December 2014, 6 January 2015 to 8 January 2015, 20 January 2015 to 29 January 2015 and 12 February 2015 to 13 February 2015.

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

3

0

Noise

Leq (30 min)

0

0

Water Quality

Suspended solids level (SS)

5

2

Turbidity level

0

0

Dissolved oxygen level (DO)

0

0

Dolphin Monitoring

Quarterly Analysis (Dec 14 to Feb 2015)

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 two environmental complaints received in relation to the environmental impact during the reporting period.

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

Environmental Complaint No.

Date of Complaint Received

Description of Environmental Complaints

COM-2014-063

3 December 2014

Noise

COM-2014-065

24 December 2014

Water Quality


 

Notifications of Summons and Prosecutions

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

Reporting Changes

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

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

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

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


1        Introduction

1.1                 Basic Project Information

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

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

1.1.3       China State Construction Engineering (Hong Kong) Ltd. was awarded by Highways Department (HyD) as the Contractor to undertake the construction works of Contract No. HY/2011/03.  The Contract is part of the HKLR Project and HKBCF Project, these projects are considered to be ˇ§Designated Projectsˇ¨, under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap 499) and EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for the Project.  The current Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/H for HKBCF were issued on 22 December 2014 and 19 January 2015, 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.  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 tenth Quarterly Environmental Monitoring and Audit (EM&A) report for the Contract which summaries the monitoring results and audit findings of the EM&A programme during the reporting period from 1 December 2014 to 28 February 2015.

1.2                Project Organisation

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

1.3                Construction Programme

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

1.4                Construction Works Undertaken During the Reporting Period

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

Table 1.1          Construction Activities during Reporting Period

Site Area

Description of Activities

Portion X

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

ˇP        Filling works behind stone platform

ˇP        Temporary stone platform construction

ˇP        Sheet piling

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

ˇP        Construction of seawall

Portion Y

ˇP        Access shaft construction for Scenic Hill Tunnel& HKBCF to Airport Tunnel

ˇP        Utility culvert excavation

ˇP        Highway Operation and Maintenance Area Building Foundation Works

West Portal

ˇP        Pipe roofing installation and excavation for Scenic Hill Tunnel

ˇP        Ventilation Building Foundation Works

Airport Express Line

ˇP        Pre-grouting and pipe piling works for Airport Express Line access shafts

Airport Road

ˇP        Excavation works for HKBCF to Airport Tunnel West (Cut & Cover Tunnel)

ˇP        Pipe Piling Cofferdam Works for  HKBCF to Airport Tunnel West (Cut & Cover Tunnel)

Kwo Lo Wan /Airport Road

ˇP        Works for diversion of Airport Road and Kwo Lo Wan Road

Kwo Lo Wan /Airport Road /Airport Express Line

ˇP        Utilities detection

Kwo Lo Wan Road

ˇP        Excavation and lateral support works at shaft 3 extension north shaft & south shaft

 


 

2        EM&A Requirement

2.1                Summary of EM&A Requirements

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

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

Table 2.1          Summary of Impact EM&A Requirements

Environmental Monitoring

Description

Monitoring Station

Frequencies

Remarks

Air Quality

1-hr TSP

AMS 5 & AMS 6

At least 3 times every 6 days

While the highest dust impact was expected.

24-hr TSP

At least once every 6 days

--

Noise

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

NMS5

At least once per week

Daytime on normal weekdays (0700-1900 hrs).

Water Quality

ˇP    Depth

ˇP    Temperature

ˇP    Salinity

ˇP    Dissolved Oxygen (DO)

ˇP    Suspended Solids (SS)

ˇP    DO Saturation

ˇP    Turbidity

ˇP    pH

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

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

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

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

3

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

Dolphin

Line-transect Methods

Northeast Lantau survey area and Northwest Lantau survey area

Twice per month

--

Mudflat

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

San Tau and Tung Chung Bay

Once every 3 months

--

 

2.2                Action and Limit Levels

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

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

Environmental Monitoring

Parameters

Monitoring Station

Action Level

Limit Level

Air Quality

1-hr TSP

AMS 5

352 µg/m3

500 µg/m3

AMS 6

360 µg/m3

24-hr TSP

AMS 5

164 µg/m3

260 µg/m3

AMS 6

173 µg/m3

Noise

Leq (30 min)

NMS 5

When one documented complaint is received

75 dB(A)

 

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

Table 2.3         Action and Limit Levels for Water Quality

Parameter (unit)

Water Depth

Action Level

Limit Level

Dissolved Oxygen (mg/L)

Surface and Middle

5.0

4.2 except 5 for Fish Culture Zone

Bottom

4.7

3.6

Turbidity (NTU)

Depth average

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

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

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

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

Suspended Solid (SS) (mg/L)

Depth average

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

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

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

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

Notes:

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

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

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

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

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

Table 2.4          Action and Limit Level for Dolphin Impact Monitoring

 

North Lantau Social Cluster

NEL

NWL

Action Level

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

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

Limit Level

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

Remarks:

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

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

                 (3)        For North Lantau Social Cluster, AL will be trigger 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 trigger 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 carried out corrective actions.  Details of site audit findings and the corrective actions during the reporting period are presented in Appendix F.

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

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

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

3.2                Air Quality Monitoring Results

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

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

Reporting Period

Monitoring

Station

Average (mg/m3)

Range (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

December 2014

AMS5

140

76 - 276

352

500

AMS6

131

72 - 239

360

January 2015

AMS5

139

86 - 229

352

AMS6

136

67 - 207

360

February 2015

AMS5

180

107 - 283

352

AMS6

175

107 - 245

360

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

Reporting Period

Monitoring

Station

Average (mg/m3)

Range (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

December 2014

AMS5

78

56-107

164

260

AMS6

130

40-218

173

January 2015

AMS5

97

56- 189

164

AMS6

123

76 - 212

173

February 2015

AMS5

81

36 - 132

164

AMS6

86

46 - 144

173

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

3.2.3       An Action Level exceedance of 24-hour TSP at AMS5 was recorded on 21 January 2015. An Action Level exceedance of 24-hour TSP at AMS6 was recorded on 16 December 2014 and 21 January 2015, respectively.

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 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)

December 2014

NMS5

60

58 ˇV 62

When one documented complaint is received

75

January 2015

58

56 ˇV 61

February 2015

59

57 ˇV 60

*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.

3.4                Water Quality Monitoring Results

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

3.4.2       During the reporting period, five Action Level exceedances and two Limit Level exceedances for suspended solid level were recorded.  No exceedances of Action and Limit Level for dissolved oxygen level and turbidity were recorded.

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

3.5                Dolphin Monitoring Results

Data Analysis

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

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

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

3.5.4       Secondly, the encounter rates were calculated using both primary and secondary survey effort collected under Beaufort 3 or below condition as in AFCD long-term monitoring study.  The encounter rate of sightings and dolphins were deduced by dividing the total number of on-effort sightings and total number of dolphins (ANI) by the amount of survey effort for the entire quarterly period (December 2014 ˇV February 2015).

3.5.5       Quantitative grid analysis on habitat use ˇV To conduct quantitative grid analysis of habitat use, positions of on-effort sightings of Chinese White Dolphins collected during the quarterly impact phase monitoring period were plotted onto 1-km2 grids among 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 ˇV When dolphins were sighted during vessel surveys, their behaviour was observed.  Different activities were categorized (i.e. feeding, milling/resting, traveling, socializing) and recorded on sighting datasheets.  This data was then input into a separate database with sighting information, which can be used to determine the distribution of behavioural data with a desktop GIS.  Distribution of sightings of dolphins engaged in different activities and behaviours would then be plotted on GIS and carefully examined to identify important areas for different activities of the dolphins. 

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

Summary of Survey Effort and Dolphin Sightings

3.5.9       During the period of December 2014 to February 2015, 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 891.50 km of survey effort was collected, with 99.6% 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, 347.05 km and 544.45 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 645.44 km, while the effort on secondary lines was 246.06 km.  Both survey effort conducted on 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 December 2014 to February 2015, a total of 15 groups of 52 Chinese White Dolphins were sighted.  All dolphin sightings were made during on-effort search.  Twelve of the 15 on-effort sightings were made on primary lines, while the other three were made on secondary lines.  In this quarterly period, all dolphin groups were sighted in NWL, while none of them were sighted in NEL.  A summary table of the dolphin sightings is shown in Annex II of Appendix J.

Distribution

3.5.13    Distribution of dolphin sightings made during monitoring surveys in December 2014 to February 2015 is shown in Figure 1 of Appendix J. Similar to recent quarters, the majority of dolphin sightings made in the present quarter were concentrated in the northwestern end of the North Lantau region, with higher concentration near the northern boundary of the survey area and around Lung Kwu Chau (Figure 1 of Appendix J).  Similar to recent quarters, the majority of dolphin sightings made in the present quarter were concentrated in the northwestern end of the North Lantau region, with higher concentration near the northern boundary of the survey area and around Lung Kwu Chau.

3.5.14    Notably, all dolphin sightings were made far away from the HKLR03/HKBCF reclamation sites or along the entire alignment of HKLR09 and Tuen Mun-Chek Lap Kok Link (TMCLKL) during this quarterly period (Figure 1 of Appendix J). 

3.5.15    Sighting distribution of the present impact phase monitoring period (December 2015 to February 2015) was compared to the one during the baseline monitoring period (September to November 2011).  In the present quarter, dolphins have completely avoided the NEL region, which was in stark contrast to their frequent occurrence around the Brothers Islands and in the vicinity of HKBCF reclamation site during the baseline period (Figure 1 of Appendix J). The nearly complete abandonment of NEL region by the dolphins has been consistently recorded in the past eight quarters, which have resulted in extremely low to zero dolphin encounter rate in this area.

3.5.16    In NWL survey area, dolphin occurrence was also drastically different between the baseline and impact phase quarters.  During the present impact monitoring period, much fewer dolphins occurred in the middle portion of North Lantau region than those during the baseline period, where dolphins supposedly moved between their core areas around Lung Kwu Chau and the Brothers Islands (Figure 1 of Appendix J).  Moreover, more dolphins were sighted near Sha Chau and Black Point during the baseline period than those during the present impact monitoring period (Figure 1 of Appendix J).  During the baseline period, a number of dolphin groups were sighted to the west of Chek Lap Kok airport (especially near the HKLR09 alignment) during the baseline period, while they have disappeared from this area during the present impact phase period.

3.5.17    Another comparison in dolphin distribution was made between the three quarterly periods of winter months in 2012-13, 2013-14 and 2014-15 (Figure 2 of Appendix J).  Among the three winter periods, no dolphin sighting was made in NEL in 2014-15, while there were two sightings made there in 2013-14, and eight sightings in 2012-13 (Figure 2 of Appendix J).  This clearly indicated a progressive decline in dolphin usage in NEL waters in the past few years.

3.5.18    Moreover, dolphins regularly occurred in the middle and western portions of North Lantau waters (especially between Black Point and Lung Kwu Chau, as well as around Sha Chau) during the winter of 2012-13, but such usage has also progressively diminished in 2013-14 and 2014-15 (Figure 2 of Appendix J).  The temporal trend indicated that dolphin usage in the overall North Lantau region has greatly diminished during the winter months of the past few years.

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 ˇV November 2011) (See Table 3.5).

Table 3.4         Dolphin Encounter Rates (Sightings Per 100 km of Survey Effort) During Reporting Period (Dec 2014 ˇV Feb 2015) 

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 (2 & 9 Dec 2014)

0.00

0.00

Set 2 (15 & 22 Dec 2014)

0.00

0.00

Set 3 (8 & 15 Jan 2015)

0.00

0.00

Set 4 (27 & 29 Jan 2015)

0.00

0.00

Set 5 (5 & 13 Feb 2015)

0.00

0.00

Set 6 (16 & 25 Feb 2015)

0.00

0.00

Northwest Lantau

Set 1 (2 & 9 Dec 2014)

2.79

5.58

Set 2 (15 & 22 Dec 2014)

1.41

1.41

Set 3 (8 & 15 Jan 2015)

4.33

21.64

Set 4 (27 & 29 Jan 2015)

7.52

37.59

Set 5 (5 & 13 Feb 2015)

1.40

1.40

Set 6 (16 & 25 Feb 2015)

0.00

0.00

 


 

Table 3.5    Comparison of average dolphin encounter rates from impact monitoring period (December 2014 ˇV February 2015) and baseline monitoring period (September ˇV November 2011)

Survey Area

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

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

Reporting Period

Baseline Monitoring Period

Reporting Period

Baseline Monitoring Period

Northeast Lantau

0.00

6.00 ˇÓ 5.05

0.00

22.19 ˇÓ 26.81

Northwest Lantau

2.91 ˇÓ 2.69

9.85 ˇÓ 5.85

11.27 ˇÓ 15.19

44.66 ˇÓ 29.85

Note:
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

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 2.77 sightings and 9.62 dolphins per 100 km of survey effort respectively, while the encounter rates of sightings (STG) and dolphins (ANI) in NEL were both nil.

3.5.21    In NEL, the average dolphin encounter rates (both STG and ANI) in the present three-month impact monitoring period were zero, and such low occurrence of dolphins in NEL have been consistently recorded in the past eight quarters (Table 3.6). It is a serious concern that dolphin occurrence in NEL in the eight quarters (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 almost vacated from NEL waters since January 2014, with only one group of four dolphins sighted since then. 

3.5.22    Moreover, the average dolphin encounter rates (STG and ANI) in NWL during the present impact phase monitoring period were also much lower (reductions of 70.5% and 74.8% respectively) than the ones recorded in the 3-month baseline period, indicating a dramatic decline in dolphin usage of this survey area during the present impact phase period (Table 3.7). 

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

 

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

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

September-November 2011 (Baseline)

6.00 ˇÓ 5.05

22.19 ˇÓ 26.81

December 2012-February 2013 (Impact)

3.14 ˇÓ 3.21

6.33 ˇÓ 8.64

March-May 2013 (Impact)

0.42 ˇÓ 1.03

0.42 ˇÓ 1.03

June-August 2013 (Impact)

0.88 ˇÓ 1.36

3.91 ˇÓ 8.36

September-November 2013 (Impact)

1.01 ˇÓ 1.59

3.77 ˇÓ 6.49

December 2013-February 2014 (Impact)

0.45 ˇÓ 1.10

1.34 ˇÓ 3.29

March-May 2014 (Impact)

0.00

0.00

June-August 2014 (Impact)

0.42 ˇÓ 1.04

1.69 ˇÓ 4.15

September-November 2014 (Impact)

0.00

0.00

December 2014-February 2015 (Impact)

0.00

0.00

Note:
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.

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

 

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

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

September-November 2011 (Baseline)

9.85 ˇÓ 5.85

44.66 ˇÓ 29.85

December 2012-February 2013 (Impact)

8.36 ˇÓ 5.03

35.90 ˇÓ 23.10

March-May 2013 (Impact)

7.75 ˇÓ 3.96

24.23 ˇÓ 18.05

June-August 2013 (Impact)

6.56 ˇÓ 3.68

27.00 ˇÓ 18.71

September-November 2013 (Impact)

8.04 ˇÓ 1.10

32.48 ˇÓ 26.51

December 2013-February 2014 (Impact)

8.21 ˇÓ 2.21

32.58 ˇÓ 11.21

March-May 2014 (Impact)

6.51 ˇÓ 3.34

19.14 ˇÓ 7.19

June-August 2014 (Impact)

4.74 ˇÓ 3.84

17.52 ˇÓ 15.12

September-November 2014 (Impact)

5.10 ˇÓ 4.40

20.52 ˇÓ 15.10

December 2014-February 2015 (Impact)

2.91 ˇÓ 2.69

11.27 ˇÓ 15.19

Note: 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.

 

3.5.23    Notably, the last eighth consecutive quarters have triggered the Action Levels under the Event and Action Plan, while the current quarter has triggered the Limit Level.  As discussed recently in Hung (2014), the dramatic decline in dolphin usage of NEL waters in 2012 and 2013 (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 in 2012.  It appeared that such noticeable decline has already extended to NWL waters progressively in 2013 and 2014.

3.5.24    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). 

3.5.25    For the comparison between the baseline period and the present quarter (ninth quarter of the impact phase being assessed), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0059 and 0.0330 respectively.  If the alpha value is set at 0.05, significant difference was detected between the baseline and present quarters in both dolphin encounter rates of STG and ANI.

3.5.26    For the comparison between the baseline period and the cumulative quarters in impact phase (i.e. first eight quarters of the impact phase being assessed), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0009 and 0.0003 respectively.  Even if the alpha value is set at 0.01, significant differences were detected in both the average dolphin encounter rates of STG and ANI (i.e. between the two periods and the locations).

3.5.27    As indicated in both dolphin distribution patterns and encounter rates, dolphin usage has been significantly reduced in NEL and NWL waters in the present quarterly period, and such low occurrence has been consistently documented in previous quarters.  This raises serious concern, as the decline in dolphin usage in North Lantau waters could possibly link to the HZMB-related construction activities.

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

Group Size

3.5.29    Group size of Chinese White Dolphins ranged from one to eight individuals per group in North Lantau region during December 2014 to February 2015.  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 (December 2014 ˇV February 2015) and Baseline Monitoring Period (SepˇV Nov 2011)

 

Average Dolphin Group Size

Reporting Period

Baseline Monitoring Period

Overall

3.47 ˇÓ 2.29 (n = 15)

3.72 ˇÓ 3.13 (n = 66)

Northeast Lantau

0.00

3.18 ˇÓ 2.16 (n = 17)

Northwest Lantau

3.47 ˇÓ 2.29 (n = 15)

3.92 ˇÓ 3.40 (n = 49)

3.5.30    The average dolphin group sizes in NWL waters during December 2014 to February 2015 were slightly smaller than the ones recorded during the three-month baseline period (Table 3.8).  Ten of the 15 groups were composed of 1-4 individuals only, while none of the dolphin group had more than 10 individuals.

3.5.31    Distribution of dolphins with larger group sizes (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 winter of 2014-15, distribution of the few dolphin groups were concentrated near Lung Kwu Chau (Figure 3 of Appendix J). This distribution pattern was very different from the baseline period, when the larger dolphin groups were distributed more evenly in NWL waters with a few more sighted in NEL waters (Figure 3 of Appendix J).

3.5.32    Notably, none of the larger dolphin groups were sighted near the HKLR03 reclamation site in the present monitoring period (Figure 3 of Appendix J).


Habitat Use

3.5.33    From December 2014 to February 2015, the most heavily utilized habitats by Chinese White Dolphins mainly concentrated around Lung Kwu Chau and the northern end of NWL survey area (Figures 4a and 4b of Appendix J).  None of the grids in NEL recorded the presence of dolphins in the present quarter.  Moreover, all grids near HKLR03/HKBCF reclamation sites, HKLR09 or TMCLKL alignment did not record any presence of dolphins during on-effort search in the present quarterly period.

3.5.34    However, it should be emphasized 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 will be presented 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 was dramatically different from the present impact monitoring period (Figure 5 of Appendix J).  During the baseline period, nine grids between Siu Mo To and Shum Shui Kok recorded moderately high to high dolphin densities, which was in stark contrast to complete absence of dolphins during the present impact phase period (Figure 5 of Appendix J). 

3.5.36    The density patterns between the baseline and impact phase monitoring periods were also very different in NWL, with higher dolphin usage 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 (Figure 5 of Appendix J).  During the present impact phase period, the dolphin usage was confined to the northwestern end of the survey area around Lung Kwu Chau.

Mother-calf Pairs

3.5.37    During the present quarterly period, no young calves (i.e. unspotted calves or unspotted juveniles) for the first time among the ten quarters of impact phase monitoring.  This absence of young calves is also in stark contrast to their regular occurrence during the baseline period.  Their absences should be of a serious concern, and the occurrence of calves should be closely monitored in the upcoming quarters.

Activities and Associations with Fishing Boats

3.5.38    Only one dolphin sighting each was associated with feeding and socializing activities respectively during the three-month study period.  The percentage of sightings associated with feeding activities during the present quarter (6.7%) was much lower than the one recorded during the baseline period (11.6%).  On the other hand, the percentage of socializing activities during the present impact phase monitoring period (6.6%) was slightly higher than the one recorded during the baseline period (5.4%).  None of the 15 dolphin groups were engaged in traveling or milling/resting behaviour.

3.5.39    Distribution of dolphins engaged in feeding and socializing activities during the present three-month period is shown in Figure 6 of Appendix J.  The lone sightings associated with feeding and socializing activities were located to the north of the airport and near Lung Kwu Chau respectively (Figure 6 of Appendix J).  Distribution of dolphin sightings associated with these activities during the impact phase was very different from the distribution pattern of these activities during the baseline period (Figure 6 of Appendix J).

3.5.40    As in the past monitoring quarters, none of the 15 dolphin groups was found to be associated with an operating fishing vessel in North Lantau waters during the present impact phase period.  The extremely rare events of fishing boat association in the present and previous quarters were consistently found, and were likely related to the recent trawl ban being implemented in December 2012 in Hong Kong waters.


 

Photo-identification and Individual Range Use

3.5.41    From December 2014 to February 2015, over 1,500 digital photographs of Chinese White Dolphins were taken during the impact phase monitoring surveys for the photo-identification work.

3.5.42    In total, 24 individuals sighted 32 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 32 re-sightings were made in NWL.

3.5.43    The majority of identified individuals were sighted only once or twice during the three-month period, with the exception of one individual (CH34) being sighted thrice.

3.5.44    Two of these 24 individuals (NL259 and NL285) were also sighted in West Lantau waters during the HKLR09 monitoring surveys for the same three-month period, showing their extensive movement between North and West Lantau regions.

Five recognized females (NL98, NL104, NL123, NL202 and WL17) were accompanied with calves during their re-sightings. Some of these mothers were frequently sighted with their calves throughout the HKLR03 impact phase monitoring period since October 2012. Individual range use

3.5.45    Ranging patterns of the 24 individuals identified during the three-month study period were determined by fixed kernel method, and are shown in Annex V of Appendix J.

3.5.46    All identified dolphins sighted in this quarter were utilizing their range use in NWL, but have avoided the 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 during the baseline period. 

3.5.47    Notably, two individuals (NL259 and NL285) sighted in NWL and NEL waters consistently in the past have extended their range use to WL waters in the present quarter.  It should be further monitored to examine whether there has been any consistent shifts of home ranges of individuals from North Lantau to West Lantau, which could also possibly be related to the HZMB-related construction works.

Action Level / Limit Level Exceedance

3.5.48    There was one Limit Level exceedance of dolphin monitoring for the quarterly monitoring data (December 2014 ˇV February 2015). According to the contractorˇ¦s information, the marine activities undertaken for HKLR03 during the quarter of December 2014 to February 2015 included reclamation, excavation of stone platform, surcharge activities, construction of seawall, temporary drainage diversion and ground investigation. There is no evidence showing the current Limit Level 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 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.  In addition, the contractor will implement proactive mitigation measures such as avoiding anchoring at Marine Departmentˇ¦s designated anchorage site ˇV Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

3.5.49    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).

3.5.50    For the comparison between the baseline period and the present quarter (ninth quarter of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0059 and 0.0330 respectively.  If the alpha value is set at 0.05, significant difference was detected between the baseline and present quarters in both encounter rates of STG and ANI.

3.5.51    For the comparison between the baseline period and the cumulative quarters in impact phase (i.e. first nine quarters of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0009 and 0.0003 respectively.  Even if the alpha value is set at 0.01, significant difference was detected in both the average dolphin encounter rates of STG and ANI (i.e. between the two periods and the locations).

3.5.52    The AFCD monitoring data during December 2014 to February 2015 has been reviewed by the dolphin specialist, and no dolphin was sighted from 103.64 km of survey effort on primary lines in NEL during the same quarter.  This review has confirmed that the extremely low occurrence of dolphins reported by the HKLR03 monitoring survey in winter 2014-15 in NEL is accurate.

3.5.53    There is no evidence showing that the sources of impact directly related to the construction works of HKLR03 that may have affected the dolphin usage in the NEL region.

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

3.5.55    A meeting was held on 27 April 2015 with attendance of ENPO, Resident Site Staff (RSS), Environmental Team (ET) and dolphin specialist for Contract No. HY/2010/02, RSS, ET, dolphin specialist and main Contractor for Contract No. HY/2011/03. The discussion/recommendation as recorded in the minutes of the meeting, which might be relevant to HKLR03 Contract are summarized below.

3.5.56    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.

3.5.57    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.

3.5.58    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.

3.5.59    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.

3.5.60    It was suggested that the protection measures (e.g., speed limit control) for the proposed Brothers Island 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.

3.5.61    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 13 December 2014.  The mudflat surface levels at the four established monitoring stations and the corresponding XYZ HK1980 GRID coordinates are presented in Table 3.8 and Table 3.9.

Table 3.8          Measured Mudflat Surface Level Results

Baseline Monitoring
(September 2012)

Impact Monitoring
(
December 2014)

Monitoring Station

Easting (m)

Northing (m)

Surface Level

Easting (m)

Northing (m)

Surface Level

(mPD)

(mPD)

S1

810291.160

816678.727

0.950

810291.034

816678.685

1.050

S2

810958.272

815831.531

0.864

810958.223

815831.493

0.915

S3

810716.585

815953.308

1.341

810716.537

815953.273

1.469

S4

811221.433

816151.381

0.931

811221.458

816151.337

1.055

 

Table 3.9          Comparison of measurement  

Comparison of measurement

Remarks and Recommendation

Monitoring Station

Easting (m)

Northing (m)

Surface Level
(mPD)

S1

-0.126

-0.042

0.100

Level continuously increased

S2

-0.049

-0.038

0.051

Level continuously increased

S3

-0.048

-0.032

0.128

Level continuously increased

S4

0.025

-0.044

0.124

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 December 2014.  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 3.10       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)

01-Dec-14

6.49

3.00

5.95

6.93

8.70

10.80

03-Dec-14

6.67

4.85

6.80

6.80

9.70

11.25

05-Dec-14

6.70

5.80

11.15

7.08

6.10

11.40

08-Dec-14

7.25

4.65

5.20

7.16

4.40

5.40

10-Dec-14

7.43

3.80

4.60

7.40

2.75

3.30

12-Dec-14

7.93

2.05

4.75

7.67

3.10

5.20

15-Dec-14

8.65

1.55

1.60

8.45

3.05

3.90

17-Dec-14

8.46

2.60

2.35

9.29

2.75

3.20

19-Dec-14

8.76

0.70

2.55

8.88

0.50

2.30

22-Dec-14

8.93

1.80

2.10

8.82

1.35

3.75

24-Dec-14

8.63

2.50

2.40

8.60

1.45

2.50

26-Dec-14

8.49

1.25

2.85

8.65

1.60

3.65

29-Dec-14

7.77

1.70

3.75

8.01

1.55

7.70

31-Dec-14

8.18

1.35

2.30

8.44

0.95

3.35

Average

7.88

2.69

4.17

8.01

3.43

5.55


 

Mudflat Ecology Monitoring

Sampling Zone

3.6.6       There are two survey areas specified under the updated EM&A Manual for the Contract, namely Tung Chung Bay and San Tau.  Tung Chung Bay survey area is divided into three sampling zones (TC1, TC2 and TC3) and there is one sampling zone at San Tau (ST).  Survey of horseshoe crabs, seagrass beds and intertidal communities were conducted in each sampling zone. The present survey was conducted in December 2014 (totally 6 sampling days between 6th and 23rd December 2014).  The locations of sampling zones are shown in Annex I of Appendix O. 

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 10th (for TC1 and TC2) and 23rd (for TC3 and ST) December 2014. The weather was cloudy on both survey days.

Seagrass Beds

3.6.8       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 10th (for TC1 and TC2) and 23rd (for TC3 and ST) December 2014.

Intertidal Soft Shore Communities

3.6.9       The intertidal soft shore community surveys were conducted in low tide period on 6th (for TC1), 7th (for TC2), 21st (for TC3) and 22nd December 2014 (for ST). 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.

3.6.10    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 was dug for visible infauna in the quadrat regardless of hand core sample was taken.

3.6.11    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.

3.6.12    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

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

Hˇ¦= -ŁU ( Ni / N ) ln ( Ni / N ) (Shannon and Weaver, 1963)

J = Hˇ¦ / 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

3.6.14    Table 3.1 and Figure 3.1 of Appendix O shows the records of horseshoe crab survey at every sampling zone. Two individuals of Carcinoscorpius rotundicauda was found in TC1 only.  Few individuals of Tachypleus tridentatus were found in sampling zones TC3 (3 ind.) and ST (5 ind.). All individuals were found on fine sand or soft mud substrata. Every sight record consisted of single individual that no grouping behaviour was observed.

3.6.15    Table 3.2 of Appendix O summarizes the survey results of horseshoe crab at every sampling zone. For Carcinoscorpius rotundicauda, the search records were 0.5 ind. hr-1 person-1 (mean prosomal width: 41.53 mm), in TC1. According to Li (2008), the prosomal width of recorded individuals ranged 32.13ˇĐ50.92 mm that was about 5.3-8.2 years old. For Tachypleus tridentatus, the search record was 0.8 ind. hr-1 person-1 (46.86 mm) and 1.3 ind. hr-1 person-1 (64.03 mm) in TC3 and ST respectively. The prosomal width of recorded individuals ranged 37.27ˇĐ72.40 mm that was about 4.6ˇV8.5 years old.

3.6.16    No marked individual of horseshoe crab was recorded in present survey. Some marked individuals were found in previous surveys conducted in Sep. 2013, Mar. 2014 and Sep. 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.

3.6.17    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

3.6.18    Figure 3.2 and 3.3 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. In contrast, much lower search record was found in other sampling zones especially TC2 (2 ind. in Sep. 2013, 1 ind. in Mar., Jun. and Sep. 2014). There was no spatial difference of horseshoe crab size (prosomal width) among the sampling zones.

3.6.19    It was obvious that ST 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, TC3 might be functioning as less important nursery ground adjacent to ST due to moderate but fluctuate number of horseshoe crab found. 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 found in TC1, TC2 and TC3 were believed foraging from the ST during high tide while it might return to ST over a certain period of time. It accounted for the variable search records in the sampling zones along the sampling months. For example, few individuals of Tachypleus tridentatus were found in TC1 only between Sep. 2012 and Sep. 2013. However it no longer appeared while few individuals of Carcinoscorpius rotundicauda were found after Mar. 2014.

Seasonal variation of horseshoe crab population

3.6.20    Throughout the monitoring period conducted, the search record of horseshoe crab declined obviously during dry season especially December (Figures 3.2 and 3.3 of Appendix O). In present survey (Dec. 2014), 2 individuals of Carcinoscorpius rotundicauda and 8 individuals of Tachypleus tridentatus were found only. Furthermore no individual of either two species was found in the previous survey of Dec. 2013. As mentioned, 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 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.

3.6.21    Between the sampling months Sep. 2012 and Dec. 2013, Carcinoscorpius rotundicauda was a less common species relative to Tachypleus tridentatus. Only 4 individuals were ever recorded in ST in Dec. 2012. This species had been believed of very low density in ST hence the encounter rate was very low. Until Mar. 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 3-4 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 Mar. to Sep. 2014, more individuals were recorded due to larger size and higher activity.

3.6.22    For Tachypleus tridentatus, sharp increase of number of individuals was recorded in ST with wet season (from Mar. to Sep. 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 period of this year. The number of individuals increased in Mar. and Jun. 2014 followed by a rapid decline in Sep. 2014. 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 in this year. Most of the individuals might have reached a suitable size strong enough to forage in subtidal habitat.

3.6.23    Figure 3.4 of Appendix O shows the changes of prosomal width of horseshoe crab Carcinoscorpius rotundicauda and Tachypleus tridentatus in ST where was regarded as an important nursery ground. As mentioned above, Carcinoscorpius rotundicauda was rarely found between Sep. 2012 and Dec. 2013 hence the data were limiting. From Mar. to Sep. 2014, the size of major population (50% records between upper and lower quartile) fluctuated between 30-40 mm and 45-60 mm. Such fluctuation should be due to variable encounter rate influenced by weather. For Tachypleus tridentatus, a consistent growing trend was observed for the major population from Dec. 2012 to Dec. 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.

Impact of the HKLR project

3.6.24    The present survey was the eighth time 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 warm weather, large number of dead individuals on the shore) is observed, it would be reported as soon as possible.

Seagrass Beds

3.6.25    Table 3.3 of Appendix O show the records of seagrass beds survey at every sampling zone. Three small patches of Zostera japonica were found on sandy substratum nearby the seaward side of mangrove area at tidal level 2.0 m above C.D. (Figure 3.5 of Appendix O). The estimated area ranged 0.3-4.2 m2 while the estimated vegetation coverage was 20-40%. The total area and average area of seagrass beds were 4.7 m2 and 1.6 m2 respectively (Table 3.4 of Appendix O). Another seagrass species Halophila ovalis (Figure 3.5 of Appendix O). was no longer found in present survey but it used to be abundant and extensive in previous surveys.

Temporal variation of seagrass beds

3.6.26    Figure 3.6 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 Mar. 2013 that grew within the large patch of seagrass Halophila ovalis. Then the patch Jun. 2014, the patch size increased obviously again (41 m2) with warmer climate. Similar to size increased and merged gradually with the warmer climate from Mar. to Jun. 2013 (15 m2). However the patch size decreased sharply and remained similar from Sep. 2013 (4 m2) to Mar. 2014 (3 m2). In previous year, the patch size decreased again and remained similar Sep. 2014 (2 m2) to Dec. 2014 (5 m2, present survey).

3.6.27    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 the Dec. 2013 (first survey). The total seagrass bed area grew steadily from 332.3 m2 in Sep. 2012 to 727.4 m2 in Dec. 2013. Flowers could be observed in the largest patch during its flowering period in Dec. 2013. In Mar. 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 Jun. 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 ˇV 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 Sep. 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 Sep. 2014, there were two tropical cyclone records in Hong Kong (7th-8th Sep.: no cyclone name, maximum signal number 1; 14th-17th Sep.: Kalmaegi maximum signal number 8SE) before the seagrass survey dated 21st Sep. 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.

3.6.28    In Dec. 2014 (present survey), all the seagrass patches of Halophila ovalis disappeared in ST. The seagrass bed of Halophila ovalis recorded in December survey was significantly different from the baseline condition. Figure 3.7 of Appendix O shows the difference of the original seagrass beds area nearby the mangrove vegetation at high tidal level between Jun. 2014 and Dec. 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

3.6.29    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 Sep. 2014. The strong water current caused by the cyclones might have given damage to the seagrass beds.

3.6.30    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).

3.6.31    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 Sep., 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 stationˇ¦s reading) and Limit Level (≤34.4 mg/L and 130% of upstream control stationˇ¦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 Sep. 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 ˇĄNotifications of Environmental Quality Limits Exceedancesˇ¦ 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.

3.6.32    Based on the weather condition and water quality results in ST, the co-occurrence of cyclone hit and turbid waters in Sep. 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.

Impact of the HKLR project

3.6.33    The present survey was the ninth survey of the EM&A programme during the construction period. Based on the results, there was a complete disappearance of seagrass Halophila ovalis in the sampling zone ST. The combined effects of cyclone hits and turbid water incidence in Sep. 2014 were believed the cause. For the turbid water incidence (i.e. exceedance of SS concentration), there was no evidence indicating correlation between the turbid water and the contract works of HKLR (e.g. construction of seawall, stone column works) as mentioned above. Hence the negative impact of HKLR project on the seagrass was not significant.

3.6.34    As long as there is no unfavourable condition to Halophila ovalis, it is believed that the seagrass beds would recover gradually in ST in the coming months. Because it is a r-strategy seagrass species that can colonize areas in short period (Fong, 1998).

3.6.35    Recently no follow-up action is suggested. In case the disappearance of seagrass beds Halophila ovalis persists until June 2015, some follow-up actions should be taken. For examples, more water quality parameters relevant to the seagrass toxicity (e.g. herbicides and heavy metals) should be included in the water quality monitoring programme. It is to investigate any seagrass toxicity present in the water that is omitted in the original EM&A programme. Moreover, seagrass transplantation may be adopted to fasten the recovery of seagrass beds.

Intertidal Soft Shore Communities

3.6.36    Table 3.5 and Figure 3.8 of Appendix O show the types of substratum along the horizontal transect at every tidal level of 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:

ˇP       In TC1, the distribution of substratum varied among three tidal levels. At high tidal level, there was higher percentage of ˇĄGravels and Bouldersˇ¦ (50%) followed by ˇĄSandsˇ¦ (30%) and ˇĄSoft mudˇ¦ (20%). At mid tidal level, ˇĄGravels and Bouldersˇ¦ (90%) was the main substratum. At low tidal level, there was higher percentage of ˇĄSandsˇ¦ (50%) followed by ˇĄGravels and Bouldersˇ¦ (30%)ˇ¦and ˇĄSoft mudˇ¦ (20%).

ˇP       In TC2, high percentage of ˇĄSandsˇ¦ (70%) were recorded at all tidal levels. ˇĄGravels and Bouldersˇ¦ (20-30%) was the second abundant at high and mid tidal levels while ˇĄSoft mudˇ¦ (20%) was the second abundant at low tidal level.

ˇP       In TC3, the distribution of substratum varied among three tidal levels. High percentages of ˇĄSandsˇ¦ (70%) was recorded at high tidal level followed by ˇĄSoft mudˇ¦ (30%). In contrast, high percentages of ˇĄSoft mudˇ¦ (70%) was recorded at mid tidal level followed by ˇĄSandsˇ¦ (30%). ˇĄGravels and Bouldersˇ¦ was the major substratum type (70%) at low tidal level.

ˇP       In ST, ˇĄGravels and Bouldersˇ¦ (100%) was the major substratum at high and mid tidal levels. ˇĄSoft mudˇ¦ (50%) and ˇĄSandsˇ¦ (40%) were mainly recorded at low tidal level.

3.6.37    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.

3.6.38    Table 3.6 of Appendix O lists the total abundance, density and number of taxon of every phylum in the present survey. A total of 10051 individuals were recorded. Mollusca was significantly the most abundant phylum (total individuals 9813, density 327 ind. m-2, relative abundance 97.6%). The second abundant phylum was Arthropoda (105 ind., 4 ind. m-2, 1.0%). The third abundant phylum was Annelida (80 ind., 3 ind. m-2, 0.8%). Relatively other phyla were very low in abundances (density £1 ind. m-2, relative abundance £0.3%). Moreover, the most diverse phylum was Mollusca (37 taxa) followed by Arthropoda (11 taxa) and Annelida (10 taxa). There was one taxon recorded only in other phyla. The complete list of collected specimens is shown in Annex III of Appendix O.

3.6.39    Table 3.7 of Appendix O shows the number of individual, relative abundance and density of each phylum in every sampling zone. The total abundance (1528-4072 ind.) varied largely among the four sampling zones although the phyla distributions were similar. In general, Mollusca was the most dominant phylum (no. of individuals: 1455-3999 ind.; relative abundance 95.2-98.2%; density 194-533 ind. m-2). Other phyla were significantly lower in number of individuals. Arthropoda (12-38 ind.; 10.5-2.5%; 2-5 ind. m-2) and Annelida (12-32 ind.; 0.5-1.5%; 2-4 ind. m-2) were the second or third abundant phyla. In ST, Cnidaria (sea anemone) was the forth abundant phylum (12 ind.; 0.6%; 2 ind. m-2). Relatively, other phyla were low in abundance among the four sampling zones (< 0.5%).

Dominant species in every sampling zone

3.6.40    Table 3.8 of Appendix O lists the abundant species (relative abundance >10%) in every sampling zone. In TC1, gastropod Batillaria multiformis was the most abundant (203 ind. m-2, relative abundance 73%) at high tidal level (major substrata: ˇĄGravels and Bouldersˇ¦ and ˇĄSandsˇ¦). At mid and low tidal levels (major substrata: ˇĄGravels and Bouldersˇ¦ and ˇĄSandsˇ¦), rock oyster Saccostrea cucullata (151-176 ind. m-2, 39-53%, attached on boulders) and gastropod Monodonta labio (40-76 ind. m-2, 12-19%) were the first and second abundant taxa. Moreover gastropod Batillaria multiformis was the third abundant (72 ind. m-2, 18%) at mid tidal levels.

3.6.41    At TC2, gastropods Cerithidea djadjariensis (68 ind. m-2, 36%), Cerithidea cingulata (26 ind. m-2, 14%) and rock oyster Saccostrea cucullata (43 ind. m-2, 26%) were common taxa at low-moderate densities (major substratum: ˇĄSandsˇ¦). At mid and low tidal levels (major substrata: ˇĄSandsˇ¦), rock oyster Saccostrea cucullata (84-136 ind. m-2, 51-52%) was the most abundant followed by gastropod Batillaria zonalis (32-39 ind. m-2, 12-24%) at low-moderate densities. Moreover, gastropod Cerithidea djadjariensis (27 ind. m-2, 10%) was another common taxon at low-moderate density at mid tidal levels.

3.6.42    At TC3, gastropod Batillaria multiformis (549 ind. m-2, 66%) was high in density at high tidal level followed by gastropod Cerithidea djadjariensis (180 ind. m-2, 22%) at moderate density (major substratum: ˇĄSandsˇ¦). At mid tidal level (major substratum: ˇĄSoft mudˇ¦), gastropod Cerithidea djadjariensis (176 ind. m-2, 54%) was the most abundant at moderate density followed by gastropod Cerithidea cingulata (69 ind. m-2, 21%). At low tidal level (major substratum: ˇĄGravels and Bouldersˇ¦), rock oyster Saccostrea cucullata (208 ind. m-2, 44%) was the most abundant at moderate density followed by gastropods Monodonta labio (126 ind. m-2, 27%) and Batillaria multiformis (49 ind. m-2, 10%) at much lower densities.

3.6.43    At ST, gastropod Batillaria multiformis was most abundant (106 ind. m-2, 35%) at moderate density at high tidal level (major substratum: ˇĄGravels and Bouldersˇ¦) followed by much less abundant gastropod Monodonta labio (68 ind. m-2, 23%) and rock oyster Saccostrea cucullata (59 ind. m-2, 20%). At mid tidal level (major substratum: ˇĄGravels and Bouldersˇ¦), rock oyster Saccostrea cucullata (145 ind. m-2, 37%) was the most abundant at moderate density. Other less abundant taxa were gastropods Lunella coronata (66 ind. m-2, 17%), Monodonta labio (64 ind. m-2, 16%) and Batillaria multiformis (38 ind. m-2, 10%) at low densities. At low tidal level (major substrata: ˇĄSandsˇ¦ and ˇĄSoft mudˇ¦), rock oyster Saccostrea cucullata (26 ind. m-2, 31%), gastropods Batillaria zonalis (20 ind. m-2, 24%) and Lunella coronata (9 ind. m-2, 11%) were abundant taxa at low densities relative to that at high and mid tidal levels.

3.6.44    There was no consistent zonation pattern of species distribution observed across all sampling zones and tidal levels. The species distribution should be affected by the type of substratum primarily. In general, gastropods Batillaria multiformis (total number of individuals: 2683 ind., relative abundance 26.7%) and Cerithidea djadjariensis (1274 ind., 12.7%) were the most commonly occurring species on sandy and soft mud substrata. Rock oyster Saccostrea cucullata (2646 ind., 26.3%) and gastropod Monodonta labio (1041 ind., 10.4%) were commonly occurring species inhabiting gravel and boulders substratum.


 

Biodiversity and abundance of soft shore communities

3.6.45    Table 3.9 of Appendix O shows the mean values of number of species, density, biodiversity index Hˇ¦ 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 in the mean number of species (5-14 spp. 0.25 m-2). But the mean densities of TC3 (328-828 ind. m-2) were highest followed by TC1 (280-390 ind. m-2) and ST (84-396 ind. m-2). TC2 was relatively lowest at mean densities (164-261 ind. m-2). The mean Hˇ¦ (1.57) and J (0.75) in ST were relatively higher than that in TC1, TC2 and TC3 (Hˇ¦: 1.15-1.33; J: 0.60-0.69).

3.6.46    Across the tidal levels, there was no consistent difference of the mean number of species, Hˇ¦ and J in all sampling zones. The mean densities were similar among the three tidal levels in TC1 (280-390 ind. m-2) and TC2 (164-261 ind. m-2). In TC3, the mean density at high tidal level (828 ind. m-2) was much higher than mid and low tidal levels (328-472 ind. m-2). In ST, the mean densities at high and mid tidal levels (300-396 ind. m-2) were much higher than low tidal level (84 ind. m-2).

3.6.47    Figures 3.9 to 3.12 of Appendix O show the temporal changes of mean number of species, mean density, Hˇ¦ and J at every tidal level and in every sampling zone along the sampling months. No consistent temporal change of any biological parameters was observed. All the parameters were under slight and natural fluctuation with the seasonal variation. Focused on present survey (Dec. 2014), declines of mean density was observed in TC1, TC2 and ST. It was believed the cause of higher mortality during cold, dry season.

Impact of the HKLR project

3.6.48    The present survey was the ninth 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 Practise 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               Environmental Exceedances

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

4.1.3       An Action Level exceedance of 24-hour TSP at AMS5 was recorded on 21 January 2015. An Action Level exceedances of 24-hour TSP at AMS6 was recorded on 16 December 2014 and 21 January 2015 respectively.

Noise  

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

Water Quality

4.1.5       During the reporting period, five Action Level exceedances and two Limit Level exceedances for suspended solid level were recorded.  No exceedances of Action and Limit Level for dissolved oxygen level and turbidity were recorded. There were no specific activities recorded during the monitoring period that would cause any significant impacts on monitoring results and no leakage of turbid water or any abnormity or malpractice was observed during the sampling exercise.  Therefore, all exceedances were considered as non-contract related. The detailed numbers of exceedances recorded during the reporting period at each impact station are summarised in Table 4.1.

Dolphin

4.1.6       There was one Limit Level exceedance of dolphin monitoring for the quarterly monitoring data (December 2014 ˇV February 2015). According to the contractorˇ¦s information, the marine activities undertaken for HKLR03 during the quarter of December 2014 to February 2015 included reclamation, excavation of stone platform, surcharge activities, construction of seawall, temporary drainage diversion and ground investigation.

4.1.7       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 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.  In addition, the contractor will implement proactive mitigation measures such as avoiding anchoring at Marine Departmentˇ¦s designated anchorage site ˇV Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

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

Table 4.1          Summary of Water Quality Exceedances

Station

Exceedance Level

DO (S&M)

DO (Bottom)

Turbidity

SS

Total Number of Exceedances

Ebb

Flood

Ebb

Flood

Ebb

Flood

Ebb

Flood

Ebb

Flood

IS5

Action Level

--

--

--

--

--

--

26 Jan 2015

--

1

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS(Mf)6

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS7

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS8

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS(Mf)9

Action Level

--

--

--

--

--

--

--

12 Jan 2015

0

1

Limit Level

--

--

--

--

--

--

5 Dec 2014

--

1

0

IS10

Action Level

--

--

--

--

--

--

--

21 Jan 2015

0

1

Limit Level

--

--

--

--

--

--

--

--

0

0

SR3

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

SR4

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

SR5

Action Level

--

--

--

--

--

--

--

21 Jan 2015

23 Jan 2015

0

2

Limit Level

--

--

--

--

--

--

--

--

0

0

SR10A

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

23 Jan 2015

0

0

SR10B

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

Total

Action

0

0

0

0

0

0

1

4

5**

Limit

0

0

0

0

0

0

1

1

2**

Notes:

S: Surface;

M: Mid-depth;

**   The total exceedances. 

 

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

4.2.1         There were two environmental complaints received during the reporting period. The summary of environmental complaints is presented in Table 4.2. The details of cumulative statistics of Environmental Complaints are provided in Appendix N.

Table 4.2          A Summary of Environmental Complaints for the Reporting Period

Environmental Complaint No.

Date of Complaint Received

Description of Environmental Complaints

COM-2014-063

3 December 2014

Noise

COM-2014-065

24 December 2014

Water Quality

 

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               Comments

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

ˇ±   The Contractor was reminded to remove the rubbish from the shore of S16, S7, S11, S15, S22, S25, N1 and N20.

ˇ±   The Contractor was reminded to provide a drip tray for the chemical containers on vessel Sing Kee, N1 and N4.

ˇ±   The Contractor was reminded to spray water on the stockpile of fill material at N13.

ˇ±   The Contractor was reminded to remove the stagnant water from the drip tray at N4.

ˇ±   The Contractor was reminded to clean up the oil stains on the unpaved road at N13.

ˇ±   The Contractor was reminded to remove the rubbish in the U channel and divert the wastewater to a treatment facility for treatment at N13.

ˇ±   The Contractor was reminded to provide a drip tray for the oil drums at S11 and S25.

ˇ±   The Contractor was reminded to provide sorting for the waste generated from the Contact and disposed of them regularly.

ˇ±   The Contractor was reminded to clean up the stagnant water at N1, N20, S11, S19, WA4 and WA6.

ˇ±   The Contractor was reminded to replace the broken rubbish bin at N13.

ˇ±   The Contractor was reminded to clean up the oil stains inside the sheet pile at S11.

ˇ±   The Contractor was reminded to spray water during the percussive activity at S15.

ˇ±   The Contractor was reminded to clean up the slurry which observed on barge edge of vessel Shun Tat 82.

ˇ±   The Contractor was reminded to remove the excess fill material on barge edge of vessel Kiu Tak.

ˇ±   The Contractor was reminded to clean up the muddy water at S7 and S8.

ˇ±   The Contractor was reminded to clean up the oil stains and provide a drip tray for the air compressor at N4.

ˇ±   The Contractor was reminded to replace the broken sand bags along the barge edge.

ˇ±   The Contractor was asked to stop discharging the untreated wastewater into the sea at S11 and treat the wastewater prior to discharge.

ˇ±   The Contractor was reminded to clean up the sundries at S15.

ˇ±   The Contractor was reminded to spray water for the stockpiles of fill material at S22 a d N13.

ˇ±   The Contractor was reminded to remove the crushed stones and keep functional of the wheel washing bay at N20.

ˇ±   The Contractor was reminded to provide bunds/sand bags along gullies at N20 to prevent washing away of sand into the gullies.

ˇ±   The Contractor was reminded to provide a standard wheel washing facility at S8A.

ˇ±   The Contractor was reminded to divert the muddy water to a waste water facility for treatment prior to discharge.

ˇ±   The Contractor was reminded to close the gap between silt curtain sections at Portion X.

ˇ±   The Contractor was reminded to provide a cover for the rubbish bin at N4.

ˇ±   The Contractor was reminded to place sand bags around the gully at N20.

ˇ±   The Contractor was reminded to provide a drip tray and labels for chemical containers at N20.

ˇ±   The Contractor was reminded to treat the wastewater properly at N4.

ˇ±   The Contractor was reminded to provide the sand bags around the gutter to prevent washing away of silt/sand into the drainage system at N20.

ˇ±   The Contractor was reminded to remove the broken water barrier at S7

ˇ±   The Contractor was reminded to provide water spray for the breaking activity at S11.

ˇ±   The Contractor was reminded to fully enclose the cement mixing plant at S15.

ˇ±   The Contractor was reminded to remove the excess rubbish regularly at N1 and S19.

ˇ±   The Contractor was reminded to remove the concrete waste at N13.

ˇ±   The Contractor was reminded to provide water spraying for the dry unpaved road at S16.

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 contractˇ¦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               Conclusions

5.3.1         The construction phase and EM&A programme of the Contract commenced on 17 October 2012. This is the tenth Quarterly EM&A Report which summarises the monitoring results and audit findings of the EM&A programme during the reporting period from 1 December 2014 to 28 February 2015.

Air Quality

5.3.2          For AMS5, no Action and Limit Level exceedances of 1-hr TSP and 24-hr TSP were recorded at AMS 5 during the reporting period.

5.3.3          For AMS6, no Action and Limit Level exceedances of 1-hr TSP level and no Limit Level exceedances of 24-hr TSP were recorded during the reporting period. An Action Level exceedance of 24-hr TSP level was recorded on 15 and 27 October 2014, respectively.


 

Noise

5.3.4         For construction noise, there were no Action Level and Limit Level exceedances during the reporting period. 

Water Quality

5.3.5         During the reporting period, nine Action Level exceedances and three Limit Level exceedances of suspended solid level were recorded. No Action and Limit Level exceedances of dissolved oxygen level were recorded. No Action and Limit Level exceedances of turbidity were recorded.

Dolphin

5.3.6         There was one Limit Level exceedance of dolphin monitoring for the quarterly monitoring data (December 2014 ˇV February 2015).

5.3.7         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.

5.3.8         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 in 2012-15, and many individuals have shifted away from the important habitat around the Brothers Islands.

5.3.9         It is critical to 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

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

5.3.11      Impact water quality monitoring in San Tau (monitoring station SR3) was conducted in December 2014.  The monitoring parameters included dissolved oxygen (DO), turbidity and suspended solids (SS).

Mudflat - Ecology

5.3.12      The December 2014 survey was the ninth survey of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project were not detected on horseshoe crabs and intertidal soft shore community. It was found that there was a complete disappearance of seagrass Halophila ovalis in the sampling zone ST. The combined effects of cyclone hits and turbid water incidence in Sep. 2014 were believed the cause. For the turbid water incidence (i.e. exceedance of SS concentration), there was no evidence indicating correlation between the turbid water and the contract works of HKLR (e.g. construction of seawall, stone column works) as mentioned above. Hence the negative impact of HKLR project on the seagrass was not significant. Recently no follow-up action is suggested. In case the disappearance of seagrass beds Halophila ovalis persists until June 2015, some follow-up actions should be taken.

Environmental Site Inspection and Audit

5.3.13      Environmental site inspection was carried out on 3, 10, 17, 24 and 30 December 2014, 7, 14, 21 and 30 January 2015 and 4, 11, 17 and 27 February 2015. Recommendations on remedial actions were given to the Contractors for the deficiencies identified during the site inspections.

5.3.14      There were two environmental complaints received during the reporting period.

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


Figures

 


 

Appendix A

Environmental Management Structure

Appendix B

Construction Programme


 

Appendix C

Location of Works Areas


 

Appendix D

Event and Action Plan


 

Appendix E

Implementation Schedule of Environmental Mitigation Measures


 

Appendix F

Site Audit Findings and Corrective Actions


 

Appendix G

Air Quality Monitoring Data and Graphical Plots

 


 

Appendix H

Noise Monitoring Data and Graphical Plots


 

Appendix I

Water Quality Monitoring Data and Graphical Plots

Appendix J

Dolphin Monitoring Results


 

Appendix K

Waste Flow Table


 

Appendix L

Summary of Environmental Licenses and Permits


 

Appendix M

Record of ˇ§Notification of Environmental Quality Limit Exceedances

 


 

Appendix N

Cumulative Statistic on Complaints


 

 

Appendix O

Mudflat Monitoring Results