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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.4 (June 2013 to August 2013)

 

5 June 2014

 

Revision 2

 

 

 

 

 

 

 

 

 

 

 

 

 

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. 8

3.6                          Mudflat Monitoring Results. 15

3.7                          Solid and Liquid Waste Management Status. 22

3.8                          Environmental Licenses and Permits. 22

3.9                          Reference. 22

4....... Environmental Complaint and Non-compliance. 23

4.1                          Environmental Exceedances. 23

4.2                          Summary of Environmental Complaint, Notification of Summons and Successful Prosecution. 25

5....... COMMENTS, RECOMMENDATIONS AND CONCLUSION.. 26

5.1                          Comments. 26

5.2                          Recommendations. 27

5.3                          Conclusions. 28

 

 

 

 

 

 

 

 

 

Figures

 

Figure 1.1        Location of the Site

Figure 2.1         Environmental Monitoring Stations     

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

 

                           

Appendices

 

Appendix A       Environmental Management Structure

Appendix B       Construction Programme

Appendix C       Location of Works Areas

Appendix D       Event and Action Plan  

Appendix E       Implementation Schedule of Environmental Mitigation Measures

Appendix F       Site Audit Findings and Corrective Actions

Appendix G      Air Quality Monitoring Data and Graphical Plots

Appendix H       Noise Monitoring Data and Graphical Plots

Appendix I         Water Quality Monitoring Data and Graphical Plots

Appendix J        Dolphin Monitoring Results

Appendix K       Waste Flow Table

Appendix L       Summary of Environmental Licenses and Permits

Appendix M      Record of Notification of Environmental Quality Limit Exceedances

Appendix N       Cumulative Statistics on Complaints

Appendix O      Mudflat Monitoring Results

                                                                                                                                                               

 


Executive Summary

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

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

China State Construction Engineering (Hong Kong) Ltd. was awarded by Highways Department as the Contractor to undertake the construction works of Contract No. HY/2011/03.  The main works of the Contract include land tunnel at Scenic Hill, tunnel underneath Airport Road and Airport Express Line, reclamation and tunnel to the east coast of the Airport Island, at-grade road connecting to the HKBCF and highway works of the HKBCF within the Airport Island and in the vicinity of the HKLR reclamation.  The Contract is part of the HKLR Project and HKBCF Project, these projects are considered to be ¡§Designated Projects¡¨, under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap 499) and Environmental Impact Assessment (EIA) Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for the Project.  The current Environmental Permit (EP) EP-352/2009/C for HKLR and EP-353/2009/G for HKBCF were issued on 5 September 2013 and 6 August 2013, 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 fourth 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 June 2013 to 31 August 2013.

Environmental Monitoring and Audit Progress

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

Monitoring Activity

Monitoring Date

June 2013

July 2013

August 2013

Air Quality

1-hr TSP

3, 7, 13, 18, 24 and 28

4, 10, 16, 22 and 26

1, 7, 13, 19, 23 and 29

24-hr TSP

6, 11, 17, 21 and 27

AMS5: 3, 11, 15, 19, 25 and 31

AMS6: 3, 10, 15, 19, 25 and 31

6, 12, 16, 22 and 28

Noise

3, 13, 18 and 28

4, 10, 16 and 22

1, 7, 13, 19 and 29

Water Quality

3, 5, 7, 10, 12, 14, 17, 19, 21, 24, 26 and 28

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

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

Chinese White Dolphin

7, 13, 18 and 27

4, 11, 15 and 16

1, 7, 12 and 22

Mudflat Monitoring (Ecology)

8, 9, 10, 11, 12 and 22

-

-

Mudflat Monitoring (Sedimentation rate)

7 and 8

-

-

Site Inspection

4, 11, 18 and 28

2, 9, 16, 23 and 30

6, 13, 20 and 30

Due to adverse weather condition, the water monitoring at stations CS2, IS5, IS(Mf)6, IS7, IS8, IS(Mf)9, IS10, SR3, SR4 and SR5 was cancelled for mid-flood tide on 24 June 2013.

Due to adverse weather condition, the water monitoring at stations SR10A, SR10B and CS(Mf)5 were cancelled for mid-flood tide on 1 July 2013.

Due to adverse weather condition, the water quality monitoring at all stations were cancelled on 2 and 14 August 2013 during mid-ebb tide and mid-flood tide and at stations IS5, IS(Mf)6, IS7, IS8, IS(Mf)9, IS10, SR3, SR4 and SR5 on 30 August 2013 during mid-ebb tide.

The 24-hr TSP monitoring results obtained at stations AMS5 and AMS6 on 9 July 2013 were considered invalid as sampling duration was greater than 24 hours. The 24-hr TSP monitoring at station AMS6 was rescheduled on 10 July 2013 for station AMS6 and 11 July 2013 for AMS5.Due to adverse weather condition, the dolphins monitoring on 23 August 2013 was cancelled and rescheduled to 22 August 2013.

Breaches of Action and Limit Levels

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

Environmental Monitoring

Parameters

Action Level (AL)

Limit Level (LL)

Air Quality

1-hr TSP

0

0

24-hr TSP

0

0

Noise

Leq (30 min)

1

0

Water Quality

Suspended solids level (SS)

4

1

Turbidity level

0

0

Dissolved oxygen level (DO)

3

3

Dolphin Monitoring

Quarterly Analysis (June to August 2013)

2

0

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

There were two Action Level exceedances of dolphin monitoring for the quarterly monitoring data (June ¡V August 2013).

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

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


 

 

Environmental Complaint No.

Date of Complaint Received

Description of Environmental Complaints

COM-2013-027

29 June 2013

Noise

 

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 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 on 1 July 2013, as such the original impact water quality monitoring location at IS(Mf)9 was temporarily shifted outside the silt curtain. The new co-ordinates of station IS(Mf)9 are 813226E and 818708N since 1 July 2013.


1        Introduction

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

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

1.1.3      China State Construction Engineering (Hong Kong) Ltd. was awarded by Highways Department (HyD) as the Contractor to undertake the construction works of Contract No. HY/2011/03.  The Contract is part of the HKLR Project and HKBCF Project, these projects are considered to be ¡§Designated Projects¡¨, under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap 499) and Environmental Impact Assessment (EIA) Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for the Project.  The current Environmental Permit (EP) EP-352/2009/C for HKLR and EP-353/2009/G for HKBCF were issued on 5 September 2013 and 6 August 2013, 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 Fourth 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 June 2013 to 31 August 2013.

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

1.3                Construction Programme

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

1.4                Construction Works Undertaken During the Reporting Period

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

Table 1.1          Construction Activities during Reporting Period

Site Area

Description of Activities

Portion X

¡P        Removal of existing rock for existing seawall

¡P        Stone column installation

¡P        Sand filling behind stone platform in according to EP requirement

¡P        Temporary stone platform construction

¡P        Band drains Installation

Portion Y

¡P        Access shaft construction for SHT & HAT

¡P        Utility culvert excavation

West Portal

¡P        Site formation

¡P        Tree felling

¡P        Slope protection/ stabilization (soil nailing works)

¡P        Boulder removal/ stabilization works

Kwo Lo Wan /Airport Road

¡P        Works for diversion of Airport Road and Kwo Lo Wan Road

Airport Express Line

¡P        Pre-grouting and pipe piling works for AEL access shafts

Kwo Lo Wan /Airport Road /Airport Express Line

¡P        Utilities detection

¡P        Establishment of site access

¡P        Works for east access 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

¡P    Depth

¡P    Temperature

¡P    Salinity

¡P    Dissolved Oxygen (DO)

¡P    Suspended Solids (SS)

¡P    DO Saturation

¡P    Turbidity

¡P    pH

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

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

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

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

3

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

Dolphin

Line-transect Methods

Northeast Lantau survey area and Northwest Lantau survey area

Twice per month

--

Mudflat

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

San Tau and Tung Chung Bay

Once every 3 months

--

 

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

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

Environmental Monitoring

Parameters

Monitoring Station

Action Level

Limit Level

Air Quality

1-hr TSP

AMS 5

352 µg/m3

500 µg/m3

AMS 6

360 µg/m3

24-hr TSP

AMS 5

164 µg/m3

260 µg/m3

AMS 6

173 µg/m3

Noise

Leq (30 min)

NMS 5

When one documented complaint is received

75 dB(A)

 

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

Table 2.3         Action and Limit Levels for Water Quality

Parameter (unit)

Water Depth

Action Level

Limit Level

Dissolved Oxygen (mg/L)

Surface and Middle

5.0

4.2 except 5 for Fish Culture Zone

Bottom

4.7

3.6

Turbidity (NTU)

Depth average

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

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

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

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

Suspended Solid (SS) (mg/L)

Depth average

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

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

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

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


 

Notes:

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

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

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

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

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

Table 2.4          Action and Limit Level for Dolphin Impact Monitoring

 

North Lantau Social Cluster

NEL

NWL

Action Level

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

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

Limit Level

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

Remarks:

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

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

                 (3)        For North Lantau Social Cluster, AL will be 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 Contractors 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 were observed.  The relevant records were kept properly. 

3.1.5      A dolphin exclusion zone of 250m was implemented during the maintenance of silt curtains on 14, 15, 17, 18 and 19 June 2013 and 16 and 17 August 2013.  No dolphins were observed. The relevant records were kept properly. 

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

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

 

Reporting Period

Monitoring

Station

Average (mg/m3)

Range (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

June 2013

AMS5

22

4 ¡V 51

352

500

AMS6

19

6 ¡V 42

360

July 2013

AMS5

11

5 ¡V 21

352

AMS6

11

7 ¡V 15

360

August 2013

AMS5

17

6 ¡V 40

352

AMS6

18

9 ¡V 29

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)

June 2013

AMS5

20

7 ¡V 31

164

260

AMS6

22

14 ¡V 31

173

July 2013

AMS5

12

5 ¡V 26

164

AMS6

17

10 ¡V 35

173

August 2013

AMS5

34

10 ¡V 47

164

AMS6

35

10 ¡V 62

173

 

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)

June 2013

NMS5

66

68 ¡V 72

When one documented complaint is received

75

July 2013

58

57 ¡V 60

August 2013

59

58 ¡V 61

*+3dB(A) Facade correction included

3.3.2      There was one Action Level exceedances for noise during daytime on normal weekdays.

3.3.3      A complaint was received on 29 June 2013 regarding noise generated from the works area near the site office (WA6) around 10:00 hrs on 29 June 2013.  According to the site dairy provided by the Contractor, electric circular saw was used to cut plastic tubes for maintenance work at the works area near the site office (Work area WA6) from 09:45 to 10:15 hrs of 29 June 2013.  A site inspection was undertaken on 2 July 2013, no construction works was undertaken at work area near the site office (Work area WA6). No significant noise was generated from the site. As the electric circular saw was used for maintenance work and there was no significant noise generated from the site, the complaint was considered invalid. 

3.3.4      No Limit Level exceedances were recorded during the reporting period.

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

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

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

Data Analysis

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

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

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

3.5.4      Secondly, the encounter rates were calculated using both primary and secondary survey effort collected under Beaufort 3 or below condition as in AFCD long-term monitoring study.  The encounter rate of sightings and dolphins were deduced by dividing the total number of on-effort sightings (STG) and total number of dolphins (ANI) by the amount of survey effort for the entire quarterly period (June - August 2013).

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

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

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

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

 

where        S = total number of on-effort sightings

D = total number of dolphins from on-effort sightings

E = total number of units of survey effort

SA% = percentage of sea area

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

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

Summary of Survey Effort and Dolphin Sightings

3.5.9      During the reporting period, 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 886.72 km of survey effort was collected, with 92.1% 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, 345.76 km and 540.96 km of survey effort were conducted in NEL and NWL survey areas respectively.  In addition, the total survey effort conducted on primary lines was 651.95 km, while the effort on secondary lines was 234.77 km.  Survey effort conducted on primary and secondary lines were both considered as on-effort survey data. Summary table of the survey effort is shown in Annex I of Appendix J.

3.5.11    During the six sets of monitoring surveys in June to August 2013, a total of 45 groups of 154 Chinese White Dolphins were sighted.  All except three sightings were made during on-effort search.  Twenty-nine on-effort sightings were made on primary lines, while another thirteen on-effort sightings were made on secondary lines.  5 groups of 13 dolphins were sighted in NEL, while the other 40 groups of 141 dolphins were sighted in NWL.  Summary table of the dolphin sightings is shown in Annex II of Appendix J.

Distribution

3.5.12    Distribution of dolphin sightings made during monitoring surveys in June July and August 2013 was shown in Figure 1 of Appendix J. The majority of sightings were concentrated in the northwestern portion of North Lantau region, especially around Lung Kwu Chau, Sha Chau and Black Point. Several sightings were made near Shum Wat, to the north of the airport and near Pillar Point. The sightings made in NEL were scattered along the north shore of Lantau, particularly near Yam O. Only one sighting was made in the vicinity of the Brothers Islands. 

3.5.13    No dolphin was sighted in the vicinity of the HKLR03 reclamation site (Figure 1 of Appendix J). Two sightings were made within a few kilometres of the HKBCF reclamation site (one near Siu Ho Wan and another to the north of Tai Mo To), adjacent to the future Tuen Mun-Chek Lap Kok Link (TM-CLKL) alignment. On the other hand, five sightings were made along and near the HKLR09 alignment to the west of the airport platform.

3.5.14    When compared with the sighting distribution of dolphins during baseline monitoring surveys in September to November 2011, dolphins rarely occurred in NEL region during the present impact monitoring period, in contrast with their frequent occurrence around the Brothers Islands and HKBCF reclamation site during the baseline period (Figure 1 of Appendix J). The low occurrence of dolphins around the Brothers Islands and Shum Shui Kok in the present quarter was similar to the previous quarter, and should be a concern as the future marine park will be established in this region as a compensation measure for the habitat loss resulted from the HKBCF and HKLR reclamation works. 

3.5.15    On the other hand, dolphin occurrence in the western portion of North Lantau region was similar between the two periods (Figure 1 of Appendix J).

Encounter Rate

3.5.16    For the three-month study period in June, July and August 2013,  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) from each of the survey areas 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 in September to November 2011 (See Table 3.5).

Table 3.4         Dolphin Encounter Rates (Sightings Per 100 km of Survey Effort) During three Reporting Period (June 2013 ¡V August 2013) 

Survey Area

Dolphin Monitoring

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

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

Primary Lines Only

Primary Lines Only

Northeast  Lantau

Set 1 (7 & 13 Jun 2013)

2.60

20.83

Set 2 (18 & 27 Jun 2013)

0.00

0.00

Set 3 (4 & 11 Jul 2013)

2.65

2.65

Set 4 (15 & 16 Jul 2013)

0.00

0.00

Set 5 (1 & 17 Aug 2013)

0.00

0.00

Set 6 (12 & 22 Aug 2013)

0.00

0.00

Northwest Lantau

Set 1 (7 & 13 Jun 2013)

5.87

29.33

Set 2 (18 & 27 Jun 2013)

5.67

17.01

Set 3 (4 & 11 Jul 2013)

11.58

57.92

Set 4 (15 & 16 Jul 2013)

4.55

12.12

Set 5 (1 & 7 Aug 2013)

1.62

8.08

Set 6 (12 & 22 Aug 2013)

10.10

37.52

 


 

Table 3.5         Comparison of Average Dolphin Encounter Rates between Reporting Period (Jun 2013 ¡V Aug 2013) and Baseline Monitoring Period (Sep¡V Nov 2011) (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)

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

0.88 ¡Ó 1.36

6.00 ¡Ó 5.05

3.91 ¡Ó 8.36

22.19 ¡Ó 26.81

Northwest Lantau

6.56 ¡Ó 3.68

9.85 ¡Ó 5.85

27.00 ¡Ó 18.71

44.66 ¡Ó 29.85

 

3.5.17    In NEL, the average dolphin encounter rates (both STG and ANI) in the present three-month study period were much lower (reductions of 85% and 82% respectively) than the ones recorded in the 3-month baseline period (Table 3.5). In fact, dolphin occurrence in NEL in the present and previous quarters have been exceptionally low, and therefore the historical data in the past few years were also examined to elucidate the cause of such dramatic decline in dolphin encounter rates in this area.

3.5.18    Using only the survey effort and on-effort sighting data collected on primary lines, the encounter rates deduced from the advanced HZMB monitoring data in summer 2011 (June-August) were 8.6 (STG) and 29.0 (ANI) respectively.  By pooling the survey effort and on-effort dolphin sightings from both HZMB and AFCD monitoring data for the same period, the encounter rates in summer 2011 were 5.8 (STG) and 17.5 (ANI).  On the other hand, the encounter rates deduced from AFCD monitoring data in summer 2012 (June-August) were 2.4 (STG) and 6.5 (ANI), which were less than 50% of the encounter rates in summer 2011.  As a comparison, the encounter rates deduced in the present quarter in summer 2013 further dropped to the 0.9 (STG) and 3.9 (ANI).

3.5.19    For the summer months (i.e. June through August), it appeared the decline in dolphin encounter rates in NEL began in 2012, and further worsened in 2013.  The sharp decline in dolphin usage in NEL is of serious concern, and should be continuously monitored in the upcoming quarter to determine whether similar decline also occurred in autumn months.

3.5.20    In NWL, the average dolphin encounter rates (STG and ANI) during the present impact phase monitoring period were also noticeably lower ((reductions of 33% and 39% respectively) than the ones recorded in the 3-month baseline period, indicating a reduced dolphin encounter rates of this survey area.  The percentages of reduction in dolphin encounter rates were also similar to the previous quarter (i.e. spring 2013).

3.5.21    In examining the historical data in summer months of 2011 and 2012, dolphin encounter rates in NWL deduced from the advanced HZMB monitoring data in 2011 were 11.9 (STG) and 44.5 (ANI) respectively.  By pooling the survey effort and on-effort dolphin sightings from both HZMB and AFCD monitoring data for the same period, the encounter rates in summer 2011 were 10.2 (STG) and 37.6 (ANI).  On the other hand, the encounter rates in NWL deduced from AFCD monitoring data in summer 2012 were 8.5 (STG) and 26.1 (ANI).  In comparison, the encounter rates deduced in summer 2013 was 6.6 (STG) and 27.0 (ANI).

3.5.22    Although the decline in dolphin encounter rates in NWL for the summer months of 2011-13 was not as dramatic as the one in NEL, dolphins appeared to diminish their usage of this area in recent years as well.  Such decline should be continuously monitored in the upcoming quarters.

3.5.23    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).

3.5.24    For the comparison between the baseline period and the present quarter (fourth quarter of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0611 and 0.1508 respectively.  If the alpha value is set at 0.1, significant difference was detected between the baseline and present quarters in the encounter rate of STG, but not the encounter rate of ANI.

3.5.25    For the comparison between the baseline period and the cumulative quarters in impact phase (i.e. first four quarters of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0559 and 0.0244 respectively.  If the alpha value is set at 0.1, significant differences were detected in both the average dolphin encounter rates of STG and ANI (i.e. between the two periods and the locations).

3.5.26    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 7.14 sightings and 25.82 dolphins per 100 km of survey effort respectively, while the encounter rates of sightings (STG) and dolphins (ANI) in NEL were 1.47 sightings and 3.82 dolphins per 100 km of survey effort respectively.

Group Size

3.5.27    Group size of Chinese White Dolphins ranged from 1- 11 individuals per group in North Lantau region during June to August 2013.  The average dolphin group sizes from these three months were compared with the one deduced from the baseline period in September to November 2011, as shown in Table 3.6.

Table 3.6         Comparison of Average Dolphin Group Sizes between Reporting Period (June 2013 to August 2013) and Baseline Monitoring Period (Sep¡V Nov 2011)

 

Average Dolphin Group Size

Reporting Period

Baseline Monitoring Period

Overall

3.42 ¡Ó 2.43 (n = 45)

3.72 ¡Ó 3.13 (n = 66)

Northeast Lantau

2.60 ¡Ó 3.05 (n = 5)

3.18 ¡Ó 2.16 (n = 17)

Northwest Lantau

3.53 ¡Ó 2.36 (n = 40)

3.92 ¡Ó 3.40 (n = 49)

 

3.5.28    The average dolphin group size in the entire North Lantau region as well as in NEL and NWL during June to August 2013 was slightly lower than the ones recorded in the 3-month baseline period (Table 3.6). 

3.5.29    Distribution of dolphins with larger group sizes during June to August 2013 is shown in Figure 2 of Appendix J, and was compared with the one in baseline period (Figure 2 of Appendix J). Overall, most of the larger dolphin groups were concentrated within the Sha Chau and Lung Kwu Chau Marine Park area during the present quarter, which is similar to the distribution in baseline period (Figure 2 of Appendix J). Only one of the five groups in sighted in NEL was classified as a larger dolphin group, which was located to the eastern end of the survey area near Yam O.  In the vicinity of the HKLR03 reclamation sites, no larger dolphin group was found there.

Habitat Use

3.5.30    From June - August 2013, the most heavily utilized habitats by Chinese White Dolphins mainly concentrated within and adjacent to the Sha Chau and Lung Kwu Chau Marine Park, as well as the Urmston Road section between Pillar Point and Lung Kwu Chau (Figures 3a and 3b of Appendix J). Only few grids in NEL recorded the presence of dolphins, and except Grid W14, most of these grids only recorded low density.  None of the grids around HKLR03 work site recorded the presence of dolphins.

3.5.31    It should be noted 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.

3.5.32    When compared with the habitat use patterns during the baseline period, dolphins usage in NEL was noticeably much lower in the present impact monitoring period (Figure 4 of Appendix J). In fact, during this quarter of summer 2013, dolphins were mostly absent from the important dolphin habitats around the Brothers and near Shum Shui Kok that were identified during the baseline period and in previous studies (e.g. Hung 2008).  From the same comparison between the two quarterly periods, it appears that dolphins have avoided the construction sites of HKLR03 in the present monitoring period, similar to what was recorded during the baseline monitoring. (Figure 4 of Appendix J).

3.5.33    The absence of dolphins in the identified important habitats around the Brothers Islands and Shum Shui Kok in the present and previous quarter is of serious concern.  The future Brothers Islands Marine Park will be established in this area upon the completion of HKBCF reclamation works, as an important compensation measure for the habitat loss in relation to HZMB projects.  It should be further examined whether the very low usage of dolphins would continue in this important dolphin habitat, and the potential measures should be implemented soon that may enhance the dolphin usage of this area.

Mother-calf Pairs

3.5.34    During the three-month study period, a total of three unspotted calves (UC) and ten unspotted juveniles (UJ) were sighted in NEL and NWL survey areas.  These young calves comprised 8.4% of all animals sighted, which was slightly higher than the percentage recorded during the baseline monitoring period (6.8%).

3.5.35    These young calves mainly occurred around Lung Kwu Chau and Black Point, which was somewhat similar to the distribution of young calves during the baseline period (Figure 5 of Appendix J).  Notably, young calves appeared to avoid the HKLR03 reclamation sites during the present quarter, similar to what was recorded during the baseline monitoring.

Activities and Associations with Fishing Boats

3.5.36    A total of four dolphin sightings were associated with feeding and socializing activities during the three-month study period. The percentages of feeding and socializing activities comprised of 6.7% and 2.2% of the total number of dolphin sightings respectively, which were much lower than the percentages recorded during the baseline period (feeding activity: 11.6%; socializing activity: 5.4%).  Only one group of dolphins was engaged in traveling activity.

3.5.37    Distribution of dolphins engaged in different activities during the three-month study period is shown in (Figure 6 of Appendix J).  The feeding activities occurred near Lung Kwu Chau and Shum Wat (along the HKLR alignment), while the lone sighting with socializing activity was located near Sha Chau.  On the other hand, one group of six dolphins was engaged in traveling activity near the Castle Peak Power Station.

3.5.38    During the three-month period, none of the 45 dolphin groups was found to be associated with an operating fishing vessel.  The extremely low level of fishing boat association in the present and previous quarters was likely related to the recent trawl ban being implemented in 2013 in Hong Kong waters.

Photo-identification and Individual Range Use

3.5.39    From June to August 2013, over 2,500 digital photographs of Chinese White Dolphins were taken during the impact phase monitoring surveys for the for the photo-identification work.

3.5.40    In total, 44 individuals sighted 71 times altogether were identified (see summary table in Annex III and photographs of identified individuals in Annex IV of Appendix J).  Only nine of these 71 re-sightings were made in NEL, which involved six individuals.  These were the same individuals that were repeatedly sighted before in NEL during the HKLR03 impact phase monitoring surveys.

3.5.41    Most identified individuals were sighted only once or twice during the three-month period, with the exception of five individuals being sighted thrice (CH98, NL24, NL33, NL202, NL286) and one individual being sighted four times (NL284).

3.5.42    Five well-recognized females, including NL33, NL104, NL123, NL202 and WL98, were accompanied with their calves during their re-sightings. Except WL98, the other four mothers were frequently seen with their calves during HKLR03 impact phase monitoring surveys.

3.5.43    Ranging patterns of the 44 individuals identified during the three-month study period were determined by fixed kernel method, and are shown in Annex V of Appendix J. 

3.5.44    Only six individuals were sighted in the NEL survey area while other individuals were mostly found in the NWL survey area during this quarterly period.  In contrast to the extensive movements between NEL and NWL survey areas in the first two impact monitoring quarters (October 2012 - February 2013) and the baseline period (September-November 2011), many of these identified individuals have avoided NEL during June-August 2013, even though they were frequently sighted there in the past decade, and their core areas were centered around the Brothers Islands (e.g. NL98, NL120, NL261) (Hung 2013) (Annex V of Appendix J). 

3.5.45    To examine whether any range use of individual dolphins has shifted away from NEL since the commencement of the HKLR03 construction works, the re-sighting locations of 21 individuals that centered their core area use around the Brothers Islands were examined from the past four quarters, and were compared to the locations of their previous re-sightings since 2002 extracted from the HKCRP long-term photo-identification catalogue (see Hung 2013).

3.5.46    Among these 21 individuals, seven individuals were re-sighted repeatedly in NWL, but were not sighted in NEL at all in the past 12 months, even though they have centered their core area use around the Brothers Islands in the past (see examples in Figure 7 of Appendix J).  Moreover, seven other individuals were sighted once or twice in NEL in the past 12 months (see examples in Figure 8 of Appendix J), but the majority of them were sighted there in autumn 2012 and winter 2012/13 and were absent in spring and summer 2013.  Notably, a few of these individuals also expanded their range use to West Lantau (e.g. CH34, NL104, NL188).

3.5.47    On the contrary, five individuals were sighted repeatedly (7-10 times) in NEL throughout the four quarters, and two of them (NL33 and NL123) occurred there with their calves (see examples in Figure 9 of Appendix J).  However, these individuals also ranged frequently to NWL and WL during the same period, even though they rarely occurred in West Lantau in the past decade.  For example, EL01 was sighted near Fan Lau, while NL120 was sighted near Peaked Hill in recent months.  Although they have not avoided the Brothers Islands for their range use, there is also indication that they have recently expanded their range use.

3.5.48    It is apparent that the majority of individual dolphins that utilized NEL waters in the past decade has either diminished or avoided this area for their recent range use.  This coincided well with the dramatic decline in dolphin occurrence in NEL as discussed in Sections 3.5.16 to 3.5.26. Although these individuals appeared to utilize NWL and even WL more frequently during the same period, the dolphin encounter rates in NWL also continued to fall in recent months, indicating that some dolphins may have diminished their overall usage in the North Lantau region, possibly linked to the HZMB-related construction works. This is of serious concern, as the Brothers Islands in NEL was once identified an important habitat for many year-round residents that focused their core area use there (Hung 2008). Therefore, the ranging pattern of individual dolphins should be continuously monitored around Lantau waters, and measures should be taken to ensure that dolphins can continue to move between NWL and NEL without any hindrance as a result of the HZMB-related construction works.

Action Level / Limit Level Exceedance

3.5.49    There were two Action Level exceedances of dolphin monitoring for the quarterly monitoring data (June ¡V August 2013). According to the contractor¡¦s information, the marine activities undertaken for HKLR03 during the two quarterly periods (March to May 2013 and June to August 2013) included stone platform construction, reclamation, stone column installation, band drain installation and excavation of stone platform.  During the quarterly period of June to August 2013, geotextile laying activities were also carried out. There is no evidence showing the current AL non-compliance directly related to the construction works of HKLR03.  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 Department¡¦s designated anchorage site ¡V Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

3.5.50    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).

3.5.51    For the comparison between the baseline period and the present quarter (fourth quarter of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0611 and 0.1508 respectively.  If the alpha value is set at 0.1 (due to the small sample size with lower statistical power in the analysis), significant difference was detected between the baseline and present quarters in the average dolphin encounter rate of STG, but not in the average dolphin encounter rate of ANI.

3.5.52    For the comparison between the baseline period and the cumulative quarters in impact phase (i.e. first four quarters of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.0559 and 0.0244 respectively.  If the alpha value is set at 0.1, significant difference was detected in both the average dolphin encounter rates of STG and ANI (i.e. between the two periods and the locations).

3.5.53    The AFCD monitoring data during June-August 2013 has been reviewed by the dolphin specialist, and only one group of six dolphins were sighted from 126.03 km of survey effort on primary lines in NEL during the same quarter.  This review has confirmed that the very low occurrence of dolphins reported by the HKLR03 monitoring survey in summer 2013 in NEL is accurate.

3.5.54    All dolphin protective measures are fully and properly implemented in accordance with the EM&A Manual.  In order to minimise disturbance to the Brother¡¦s Island, the Contractor provide training to skippers to ensure that their working vessels travel from source to destination to minimize impacts on Chinese White Dolphin and avoid anchoring at Marine Department¡¦s designated anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

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 7 and 8 June 2013.  The mudflat surface levels at the four established monitoring stations and the corresponding XYZ HK1980 GRID coordinates are presented in Table 3.7 and Table 3.8.

Table 3.7          Measured Mudflat Surface Level Results

 

Baseline Monitoring
(September 2012)

Impact Monitoring
(June 2013)

Monitoring Station

Easting (m)

Northing (m)

Surface Level

Easting (m)

Northing (m)

Surface Level

(mPD)

(mPD)

S1

810291.160

816678.727

0.950

810291.159

816678.728

1.029

S2

810958.272

815831.531

0.864

810958.244

815831.531

0.970

S3

810716.585

815953.308

1.341

810716.579

815953.323

1.423

S4

811221.433

816151.381

0.931

811221.447

816151.404

0.989

 

Table 3.8          Comparison of measurement 

 

Comparison of measurement

Remarks and Recommendation

Monitoring Station

Easting (m)

Northing (m)

Surface Level
(mPD)

S1

0.000

0.001

0.079

Level continuously increased

S2

-0.028

-0.001

0.106

Within tolerance, no significant change

S3

-0.007

0.015

0.082

Within tolerance, no significant change

S4

0.014

0.022

0.058

Within tolerance, no significant change

 

3.6.2      The measurement results for S2, S3 and S4 showed that the level has increased within tolerance and their sea bed depth would not be considered as significant change. For S1, the mudflat level has been continuously increased. The increased surface level for S1, S2, S3 and S4 is 0.079, 0.106, 0.082 and 0.058 mPD when compared to the baseline monitoring results.

Water Quality Monitoring

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

3.6.4      Impact water quality monitoring in San Tau (monitoring station SR3) was conducted in June 2013.  The monitoring parameters included dissolved oxygen (DO), turbidity and suspended solids (SS).

3.6.5      Due to adverse weather condition, the water monitoring for mid-flood tide at station SR3 was cancelled on 24 June 2013. The Impact monitoring results for SR3 were extracted and summarised below:

Table 3.9          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)

03-Jun-13

10.3

4.7

8.5

10.3

2.1

4.5

05-Jun-13

7.8

3.5

2.1

7.3

4.6

4.5

07-Jun-13

6.4

2.1

2.9

5.9

4.0

4.1

10-Jun-13

6.9

2.8

2.2

7.0

2.1

1.2

12-Jun-13

5.6

3.6

1.6

5.5

2.5

1.2

14-Jun-13

5.1

6.3

3.1

5.1

2.2

1.7

17-Jun-13

6.9

3.6

3.5

6.7

4.2

7.5

19-Jun-13

7.2

2.1

2.3

9.4

2.2

5.3

21-Jun-13

9.9

5.8

9.4

10.4

7.9

11.2

24-Jun-13

6.7

18.7

16.8

N.A

N.A

N.A

26-Jun-13

6.1

6.4

8.1

6.0

5.2

4.7

28-Jun-13

6.7

4.4

6.5

6.0

5.2

4.7

Average

7.1

5.3

5.6

7.2

3.8

4.6

 

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 locations of sampling zones are shown in Annex I of Appendix O. 

Horseshoe Crabs

3.6.7      An active search method was adopted for horseshoe crab survey at each sampling zone. The survey was undertaken by 2 specialists at each 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 was found, the species, size and inhabiting substrate, photographic record and respective GPS coordinate were recorded with reference to Li (2008). The horseshoe crab surveys were conducted on 11th (for zones TC1 and TC2) and 10th (for zones TC3 and ST) June 2013 with hot and cloudy weather with intermittent raining.

Seagrass Beds

3.6.8      An active search method was adopted for seagrass bed survey at each sampling zone.  The survey was undertaken by 2 specialists each spending within 2-3 hours in low tide period.  Once seagrass bed was observed, the species, the estimated area (m2), photographic record and respective GPS coordinate were recorded.  The seagrass bed surveys were conducted on 11th (for zones TC1 and TC2) and 10th (for zones TC3 and ST) June 2013 with hot and cloudy weather with intermittent raining.

Intertidal Soft Shore Communities

3.6.9      The sandy shore of San Tau and Tung Chung Bay from the uppermost part of the shore and to the water edge was divided into three tidal zones ¡V upper, middle and lower zones, at each sampling zone, TC1, TC2, TC3 and ST.  A 100m transect was laid in each of the three tidal zones for fauna sampling.

3.6.10    At each sampling zone, three 100m horizontal transects were laid at 2.0m, 1.5m and 1.0m above C.D.  Along each transect, ten random quadrats (0.5 m x 0.5m) were placed.  In each quadrat, the epifauna and infauna (within the top 5cm sediment) in each quadrat were identified and their numbers/coverage percentages were recorded.  One core of 10cm diameter x 20cm depth was also collected within each quadrat.  The sediments of the cores were sieved with 2mm mesh-size sieve and the biota inside was identified and counted.  All collected fauna were released after recording except some tiny individuals that in-situ identification was not feasible. These tiny individuals were collected and were identified in the laboratory.  Species and abundance of biota in both cores and quadrats were reported.  The intertidal soft shore community surveys were conducted in low tide period on 8th (for TC3), 9th (for TC1), 12th (for TC3) and 22nd June 2013 (for ST).

Data Analysis

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

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

J = H¡¦ / ln S, (Pielou, 1966)

 

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

Mudflat Ecology Monitoring Results and Conclusion

Horseshoe Crabs

3.6.12    Table 3.1 and Figure 3.1 of Appendix O show the records of horseshoe crab survey at every sampling zone. In general, horseshoe crab Tachypleus tridentatus was found at TC1 (7 individuals), TC3 (16 individuals) and ST (59 individuals).  All individuals were found on either soft mud or sandy substratum or sandy substratum surrounded by small gravels. Grouping was observed while each group consisted of 2-7 individuals only. One individual was found with lost tail at ST that might be caused by human trampling. Since the commencement of the survey (Sep. 2012), no individual was found at TC2. It showed that TC2 was not a suitable nursery ground for horseshoes crab.

3.6.13    According to Table 3.2 of Appendix O, the search records of Tachypleus tridentatus were
1.75 individuals hr-1 person-1 (mean prosomal widths: 42.94 mm) and 4.00 individuals hr-1 person-1 (34.54 mm) at TC1 and TC3, respectively. Similar to previous surveys, the highest search record of 9.83 individuals hr-1 person-1 (40.25 mm) was reported at ST.  According to Li (2008), the prosomal width of Tachypleus tridentatus recorded ranged 11.02¡Ð57.62 mm that corresponded to an estimated age of 1.7¡V6.8 years old. Summary of prosomal width of horseshoe crab is shown in Table 3.10.


 

Table 3.10       Summary of Prosomal Width of Horseshoe Crab Survey

 

Sampling Zone

TC1

TC2

TC3

ST

Search duration (hr)

2

2

2

3

Tachypleus tridentatus

 

 

 

 

 

 

No. of individuals

7

N.A.

16

59

Mean prosomal width (mm)

42.94

N.A.

34.54

40.25

Range of prosomal width (mm)

21.44-57.62

N.A.

11.07-54.56

12.54-55.51

 

 

 

 

 

Search record
(individual hr-1 person-1)

1.75

N.A.

4.00

9.83

 

 

 

 

 

 

3.6.14    The mean prosomal widths of Tachypleus tridentatus were similar among TC1, TC3 and ST. However, ST was usually inhabited by more individuals of smaller size. Larger individuals were usually found at TC1 and TC3 at lower abundance. ST was believed a more important nursery ground for horseshoe crab especially newly hatched individuals. When reaching larger size of higher mobility, few individuals might migrate to nearby sampling zones TC1 and TC3 for foraging.

Figure 3.2 of Appendix O shows the changes of number of individuals, mean prosomal width and search record of horseshoe crab Tachypleus tridentatus at the every sampling zones along the sampling months. Both number of individuals and search records declined generally at the three sampling zones during dry season (Sep. to Dec. 2012). The horseshoe crabs were inactive and burrowed in the sediments during cold weather (<15 ºC). Similar results of low search record in dry seasons were reported in a previous territory-wide survey of horseshoe crab. For example, the search records at Tung Chung Wan were 0.17 individual hr-1 person-1 and 0 individual. hr-1 person-1 in wet season and dry season respectively (details see Li, 2008). From December 2012 to June 2013 (present survey), both values increased with the warmer climate at the sampling zones.

3.6.15    Figure 3.3 of Appendix O shows the changes of prosomal width of horseshoe crab population at ST. It was believed that most of individuals (50% records between upper and lower quartile), recorded in the dry season, had grown to a size of double in the present survey (prosomal width increase from 10-20 mm to 30-50 mm). At the same time, tiny individuals (10-15 mm) were found (outliers of low value) that seasonal spawning was believed occurring at ST.

3.6.16    Another less common species Carcinoscorpius rotundicauda was not found during the whole survey period except the survey conducted in December 2012 at ST (4 individuals). This species was believed present in ST at very low number while encounter was very rare.

3.6.17    The present survey was the third time of sampling of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project could not be detected on horseshoe crabs considering the factor of natural, seasonal variation, In case, abnormal phenomenon (e.g. very few numbers of horseshoe individuals in warm weather) is observed, it would be reported as soon as possible.

Seagrass Beds

Table 3.3 and Figure 3.4 of Appendix O show the records of seagrass beds survey at every sampling zone. Two patches of Halophila ovalis were recorded nearby the mangrove vegetation at tidal level 2 m above C.D. at ST. The estimated total area and mean area were 299.9 m2 and 463.7 m2 respectively while the estimated coverage ranged 90-100%. Both patches were so close and formed a long seagrass strand with estimated total area 763.6 m2. One patch of Zostera japonica was found within the long strand of Halophila ovalis. The estimated area was 14.6 m2 while the estimated coverage ranged 70-90%.

3.6.18    Figure 3.5 of Appendix O shows the changes of estimated total area of seagrass beds at ST along the sampling months. For seagrass Halophila ovalis, the total area and estimated coverage increased gradually. It showed that the seagrass was in scattered patches during dry season then grew and merged into single patch during wet season. For seagrass Zostera japonica, it was not reported in the surveys of September and December 2012. Seasonal recruitment of few patches was reported between December and March. Then the patch size increased and merged gradually during wet season.

3.6.19    The present survey was the third time of sampling of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project could not be detected on seagrass.  In case, abnormal phenomenon (e.g. rapid reduction of seagrass patch size) was observed, it would be reported as soon as possible.

Intertidal Soft Shore Communities

3.6.20    Table 3.4 and Figure 3.5 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 investigating the substratum types (Gravels & Boulders / Sands / Soft mud) of the ten random quadrats along every horizontal transect.

3.6.21    The distribution of substratum types varied among tidal levels and sampling zones. At TC1, high percentage of ¡¥Sands¡¦ was recorded (70%) while the rest was ¡¥Gravels and Boulders¡¦ (30%) at high tidal level. High percentage of ¡¥Gravels and Boulders¡¦ (80%) was recorded at mid tidal level. Even distribution of ¡¥Gravels and Boulders¡¦ (50%) and ¡¥Sands¡¦ (40%) was recorded at low tidal level.  At TC2, high percentage of ¡¥Sands¡¦ (60-80%) was recorded at high and mid tidal levels while ¡¥Soft mud¡¦ was the major substratum (80%) at low tidal level. At TC3, high percentage of ¡¥Sands¡¦ (60-90%) was recorded at high and mid tidal levels followed by ¡¥Soft mud¡¦ (10-30%). ¡¥Gravels and Boulders¡¦ was the major substratum (70%) at low tidal level. At ST, ¡¥Gravels and Boulders¡¦ (100%) was recorded only at high tidal level. High percentage of ¡¥Gravels and Boulders¡¦ (70%) was recorded while the rest was ¡¥Sands¡¦ (30%) at mid tidal level. Even distribution of ¡¥Sands¡¦ (40%) and ¡¥Soft mud¡¦ (40%) was recorded at low tidal level.

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

3.6.23    Table 3.5 of Appendix O lists the total abundance, density and number of taxon of every phylum in the present survey. A total of 17329 individuals were recorded. Mollusks were significantly the most abundant phylum (total individuals 16751, density 558 individuals m-2, relative abundance 96.7%). The second abundant group was arthropod (total individuals: 416, density 14 individuals m-2, 2.4%) respectively. Relatively other phyla were very low in abundance (0.5%). Similarly, the most diverse phylum were mollusks (43 taxa) followed by arthropods (17 taxa) and annelids (14 taxa). The taxa of other phyla were relatively less (2 taxa). The complete list of collected specimens is provided in Annex III of Appendix O.

3.6.24    Table 3.6 of Appendix O shows the number of individual, relative abundance and density of each phylum at every sampling zone. The results were similar among the four sampling zones. In general, mollusks were the most dominant phylum (no. of individuals: 2608-5464 individual, relative abundance 95.9-97.9%). Arthropods were the second abundant phylum (no. of individuals: 51-164 individual, 1.4-3.2%) although the number of individuals was significantly lower than that of mollusks. Relatively, other phyla were very low in abundance across the four sampling zones (< 1%).

3.6.25    Table 3.7 of Appendix O lists the abundant species (relative abundance >10%) at every sampling zone. At TC1, gastropod Batillaria multiformis was clearly the dominant species (379-450 individuals m-2, relative abundance 41-56%) at high and mid tidal levels. Gastropod Cerithidea djadjariensis (105-208 individuals m-2, relative abundance 11-26%) was also abundant at high and mid tidal levels. Moreover, gastropod Monodonta labio (164 individuals m-2, relative abundance 18%) and rock oyster Saccostrea cucullata (143 individuals m-2, relative abundance 16%) were abundant at mid tidal level. At low tidal level, total abundance was lower and the species distribution was more even relatively. Rock oyster Saccostrea cucullata (66 individuals m-2, 19%), gastropods Cerithidea djadjariensis (45 individuals m-2, 13%) and Lunella coronata (44 individuals m-2, 12%) were common occurring species at low tidal level.

3.6.26    At TC2, all three tidal levels were dominated by gastropod Cerithidea djadjariensis (92-164 individuals m-2, relative abundance 31-55%). At high tidal level, gastropod Batillaria multiformis was the second abundant species (84 individuals m-2, relative abundance 21%) followed by rock oyster Saccostrea cucullata (56 individuals m-2, relative abundance 14%). At mid tidal level, rock oyster Saccostrea cucullata was the second abundant species (84 individuals m-2, 16%) followed by gastropod Monodonta labio (76 individuals m-2, relative abundance 14%). At low tidal level, the common occurring species were gastropods Cerithidea cingulata (20 individuals m-2, 12%), Batillaria multiformis (19 individuals m-2, 11%) and Batillaria zonalis (19 individuals m-2, 11%) while its abundances were much less than the most dominant gastropod Cerithidea djadjariensis.

3.6.27    At TC3, the high and mid tidal levels were mainly dominated by gastropods Batillaria multiformis (391-438 individuals m-2, relative abundance 47-52%) and Cerithidea djadjariensis (212-294 individuals m-2, 25-35%). Gastropod Cerithidea cingulata was the third abundant species (96 individuals m-2, 11%). At low tidal level, the abundant species were rock oyster Saccostrea cucullata (164 individuals m-2, 28%) followed by gastropods Monodonta labio (92 individuals m-2, 16%) and Lunella coronata (64 individuals m-2, 11%).

3.6.28    At ST, gastropod Batillaria multiformis was highly abundant (392 individuals m-2, relative abundance 63%) at high tidal level followed by gastropod Monodonta labio (127 individuals m-2, 20%). At mid tidal level, gastropod Batillaria multiformis (136 individuals m-2, relative abundance 21%) and rock oyster Saccostrea cucullata (120 individuals m-2, 19%) were most abundant of similar densities. Other less abundant species are gastropods Monodonta labio (66 individuals m-2, 10%) and Cerithidea djadjariensis (65 individuals m-2, 10%). Relatively, the abundant species gastropod Cerithidea djadjariensis (89 individuals m-2, 38%), rock oyster Saccostrea cucullata (30 individuals m-2, 13%) and gastropod Batillaria zonalis (26 individuals m-2, 11%) were lower in density at low tidal level.

3.6.29    There was no consistent zonation pattern of species distribution observed across sampling zones and tidal levels in Tung Chung Wan and San Tau. The species distribution should be determined by the type of substratum primarily. In general, gastropods Batillaria multiformis (6055 individuals, 35%), Cerithidea djadjariensis (3721 individuals, 21%), rock oyster Saccostrea cucullata (1829 individuals, 11%), gastropods Monodonta labio (1489 individuals, 9%) and Cerithidea cingulata (1031 individuals, 6%) were the most common occurring species among the four sampling zones.

3.6.30    Table 3.8 of Appendix O shows the mean values of number of species, density, H¡¦ and J of soft shore communities at every tidal level and sampling zone. Among the sampling zones, the mean number of species was generally similar and ranged 6-15 spp. 0.25 m-2. The mean densities of TC1 (349-810 individuals m-2) and TC3 (580-838 individuals m-2) were generally higher than that of ST (236-648 individuals m-2) followed by TC2 (166-525 individuals m-2). The mean biodiversity index and species evenness were similar that ranged 1.39-1.54 and 0.60-0.65 respectively.

3.6.31    Across the tidal levels, there was no difference of the mean number of species. Higher mean densities were observed at high and mid tidal levels. Usually higher mean biodiversity index and species evenness were observed at mid and low tidal levels except that at TC2.

3.6.32    Figure 3.6 of Appendix O shows the temporal changes of number of species, density, H¡¦ and J at every tidal level and sampling zone since the baseline monitoring survey (Sep 2012). No significant temporal change of any biological parameters was observed at all sampling zones. Although declined densities were reported at sampling zones TC2 (mid and low tidal levels) and TC3 (high and mid tidal levels) in dry season (Dec 2012), it was believed a natural, seasonal variation due to higher mortality and lower activity rate of intertidal fauna during cold, dry season. The densities of both sampling zones had increased along with the hot, wet season. At the same time, steady increases of number of species and biodiversity index were observed at ST (mid and low tidal levels).

3.6.33    The present survey was the third time of sampling of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project could not be detected on intertidal soft shore community.

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.

3.9.1      Buckland, S. T., Anderson, D. R., Burnham, K. P., Laake, J. L., Borchers, D. L., and Thomas, L.  2001.  Introduction to distance sampling: estimating abundance of biological populations.  Oxford University Press, London.

3.9.2      Hung, S. K.  2008.  Habitat use of Indo-Pacific humpback dolphins (Sousa chinensis) in Hong Kong.  Ph.D. dissertation.  University of Hong Kong, Hong Kong, 266 p.

3.9.3      Hung, S. K.  2012.  Monitoring of marine mammals in Hong Kong waters ¡V data collection: final report (2011-12).  An unpublished report submitted to the Agriculture, Fisheries and Conservation Department of Hong Kong SAR Government, 120 pp.

3.9.4      Hung, S. K.  2013.  Monitoring of marine mammals in Hong Kong waters ¡V data collection: final report (2012-13).  An unpublished report submitted to the Agriculture, Fisheries and Conservation Department of Hong Kong SAR Government, 168 pp

3.9.5      Jefferson, T. A.  2000.  Population biology of the Indo-Pacific hump-backed dolphin in Hong Kong waters.  Wildlife Monographs 144:1-65.

 

 

 


4        Environmental Complaint and Non-compliance

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

Air Quality

4.1.2      There were no Action and Limit Level exceedances for 1-hr TSP or 24-hr TSP recorded air quality were recorded during the reporting period.

Noise

4.1.3      There was one Action Level exceedance for noise during the daytime on normal weekdays. A complaint was received on 29 June 2013 regarding noise generated from the works area near the site office (WA6) around 10:00 hrs on 29 June 2013.According to the site dairy provided by the Contractor, electric circular saw was used to cut plastic tubes for maintenance work at the works area near the site office (Work area WA6) from 09:45 to 10:15 hrs of 29 June 2013.  A site inspection was undertaken on 2 July 2013, no construction works was undertaken at work area near the site office (Work area WA6). No significant noise was generated from the site. As the electric circular saw was used for maintenance work and there was no significant noise generated from the site, the complaint was considered invalid.

4.1.4      No Limit Level exceedances for noise were recorded during this reporting period.

Water Quality

4.1.5      During the reporting period, there are 4 Action Level exceedances and 1 Limit Level exceedances of suspended solids level.  No exceedances of turbidity level were recorded. 3 Action Level exceedances and 3 Limit Level exceedances of dissolved oxygen level. 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 were two Action Level exceedances of dolphin monitoring for the quarterly monitoring data (June ¡V August 2013). According to the contractor¡¦s information, the marine activities undertaken for HKLR03 during the two quarterly periods (March to May 2013 and June to August 2013) included stone platform construction, reclamation, stone column installation, band drain installation and excavation of stone platform.  During the quarterly period of June to August 2013, geotextile laying activities were also carried out. 

4.1.7      There is no evidence showing the current AL non-compliance directly related to the construction works of HKLR03.  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 Department¡¦s designated anchorage site ¡V 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.  In order to minimise disturbance to the Brother¡¦s Island, the Contractor provide training to skippers to ensure that their working vessels travel from source to destination to minimize impacts on Chinese White Dolphin and avoid anchoring at Marine Department¡¦s designated anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as far as practicable. 

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

--

--

--

10-06-2013

--

--

07-08-2013

--

1

1

Limit Level

--

--

--

--

--

 

--

 

 

--

--

0

0

IS(Mf)6

Action Level

--

--

--

--

--

--

07-08-2013

--

1

0

Limit Level

--

--

--

--

 

--

 

--

--

--

0

0

IS7

Action Level

--

--

--

--

--

--

07-08-2013

--

1

0

Limit Level

--

--

--

--

--

     --

--

  --

0

0

IS8

Action Level

--

--

--

--

 

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS(Mf)9

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

 

--

--

--

--

0

0

IS10

Action Level

--

--

10-06-2013

10-06-2013

--

--

--

--

1

1

Limit Level

--

--

--

--

--

--

--

--

0

0

SR3

Action Level

--

--

--

--

--

--

07-08-2013

--

1

0

Limit Level

--

--

--

--

--

--

--

--

0

0

SR4

Action Level

--

--

--

--

 

--

--

--

0

0

Limit Level

--

--

--

--

--

--

24-06-2013

--

1

 

0

SR5

Action Level

--

--

--

--

--

 --

--

--

0

0

Limit Level

--

--

--

--

--

--

--

 

 

--

 

 

0

0

SR10A

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

 --

0

0

SR10B

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

10-06-2013

29-07-2013

--

10-06-2013

--

--

--

--

0

3

Total

Action

0

0

1

2

0

0

4

0

7**

Limit

0

2

0

1

0

0

1

0

4**

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 was one environmental complaint received during this reporting period. 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. The summary of environmental complaints is presented in Table 4.2. The details of environmental complaints are presented in Appendix N.

Table 4.2          Summary of Environmental Complaints for the Reporting Period

Environmental Complaint No.

Date of Complaint Received

Description of Environmental Complaints

COM-2013-027

29 June 2013

Noise

 

4.2.2      A site inspection was undertaken by EPD on 7 June 2013 and a record of inspection was issued to the Contractor.  The Contractor was advised to repair the silt curtain provided at Portion A immediately before continuation of any filling activities and to ensure the silt curtain is fully maintained throughout the works.  The Contractor has modified the silt curtain arrangement to minimise the potential water quality impacts and provided regular maintenance for the silt curtain.

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

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

5        COMMENTS, RECOMMENDATIONS AND CONCLUSION

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

¡±  The Contractor was reminded to clean up the stagnant water inside the recesses for lifting eyes of concrete blocks at S16.

¡±  The Contractor was reminded to provide a drip tray for chemical container at West Portal.

¡±  The Contractor was reminder to clean up the stagnant water inside the chemical waste storage box at West Portal.

¡±  The Contractor was reminded to provide drip trays for oil containers at S5.

¡±  The Contractor was reminded to provide drip trays for chemical containers at West Portal.

¡±  The Contractor was reminded to spray water regularly on the unpaved area at WA04.

¡±  The Contractor was reminded to provide drip trays for chemical containers at WA03.

¡±  The Contractor was reminded to spray water regularly on the unpaved road at S7.

¡±  The Contractor was reminded to clean up the stagnant water inside the rubbish bin at West Portal.

¡±  The Contractor was reminded to spray water on the unpaved road at West Portal.

¡±  Bags of cement should be covered entirely with impervious sheeting at West Portal.

¡±  Empty chemical containers should be removed or properly stored at chemical waste store.

¡±  The Contractor was recommended to provide drip trays for chemical containers at S5.

¡±  The Contractor was recommended to clean up the stagnant water on the construction material at S9.

¡±  The Contractor was reminded to clean up the stagnant water inside the drip tray at N4.

¡±  The Contractor was reminded to clean up the stagnant water on the oil containers at S5.

¡±  The Contractor was reminded to clean up the stagnant water inside the drip tray at S16.

¡±  The Contractor was reminded to provide drip trays for chemical containers at S11.

¡±  The Contractor was reminded to provide fencing protection around the trees at S5.

¡±  The Contractor was reminded to clean up the stagnant water inside the drip tray at West Portal.

¡±  The Contractor was reminded to clean up the stagnant water inside the metal material at WA03.

¡±  The Contractor was reminded to provide clear labels for chemical containers at N4.

¡±  The Contractor was reminded to provide drip tray for the chemical containers at West Portal.

¡±  The Contractor was reminded to provide proper maintenance for the slit curtain at Portion X.

¡±  The Contractor was reminded to clean up the passageway of the vessel to avoid washing sand into sea form Chan Sheng 309.

¡±  The Contractor was reminded to provide an impervious shelter with top and 3 sides for the cement mixing plant at S23.

¡±  The Contractor was reminded to ensure the vehicles are thoroughly cleaned before leaving the site at S11.

¡±  The Contractor was reminded to avoid placing materials near the trees and protection to trees identified as ¡§retained¡¨/ ¡§transplant¡¨ should be provided at S8.

¡±  The Contractor was reminded to clean up stagnant water immediately to avoid mosquito breeding at N4.

¡±  The Contractor was reminded to provide proper maintenance for the slit curtain at Portion X.

¡±  The Contractor was reminded to provide regularly water spraying at N13.

¡±  The Contractor was reminded to clean up the stagnant water at S8.

¡±  The Contractor was reminded to provide proper maintenance for the rubber hose and clean up the leaked oil at S8.

¡±  The Contractor was reminded to provide drip trays for chemical containers at N5.

¡±  The Contractor was reminded to provide drip trays for the chemical containers at WA03.

¡±  The Contractor was reminded to provide drip trays for the oil containers at S11.

¡±  The Contractor was reminded to clean up the muddy water on the road at S8.

¡±  The Contractor was reminded to provide maintenance for the machine at S16

¡±  The Contractor was reminded to clean up the oil at S8.

¡±  The Contractor was reminded to clean up the stagnant water at West Portal.

¡±  The Contractor was reminded to provide drip trays for the chemical containers at N4.

¡±  The Contractor was reminded to provide cover for the cement bags at S23.

¡±  The Contractor was reminded to remove the construction material near the tree at S8.

5.2               Recommendations

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

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


 

5.3.1      The construction phase and EM&A programme of the Contract commenced on 17 October 2012 and this is the forth Quarterly EM&A Report summarises the monitoring results and audit findings of the EM&A programme during the reporting period from 1 June 2013 to 31 August 2013.

5.3.2      For air quality, there were no Action and Limit Level exceedances for 1-hr TSP or 24-hr TSP recorded during this reporting period.

5.3.3      For construction noise, there was 1 Action Level exceedances of noise were recorded during the reporting period. All noise exceedances were considered not related to project. No Limit Level exceedances for noise were recorded at the monitoring station during the reporting period. 

5.3.4      During the reporting period, there are 4 Action Level exceedances and 1 Limit Level exceedances of suspended solids level.  3 Action Level exceedances and 3 Limit Level exceedances of dissolved oxygen level were recorded.  

5.3.5      There were two Action Level exceedances of dolphin monitoring for the quarterly monitoring data (June ¡V August 2013).

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

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

5.3.8      Therefore, it is critical to monitor the dolphin usage in North Lantau region in the upcoming months, to determine whether the dolphins have been affected by the various construction activities in relation to the HZMB works, and whether suitable mitigation measure can be applied to revert the situation.

5.3.9      For sedimentation rate monitoring of mudflat, the measurement results for S2, S3 and S4 showed that the level has increased within tolerance and their sea bed depth would not be considered as significant change. For S1, the mudflat level has been continuously increased. The increased surface level for S1, S2, S3 and S4 is 0.079, 0.106, 0.082 and 0.058 mPD when compared to the baseline monitoring results.

5.3.10    Impact water quality monitoring in San Tau (monitoring station SR3) was conducted in June 2013. The monitoring parameters included dissolved oxygen, turbidity and suspended solids.

5.3.11    An active search method was adopted for horseshoe crab survey at each sampling zone. In general, horseshoe crab Tachypleus tridentatus was found at TC1 (7 individuals), TC3 (16 individuals) and ST (59 individuals).  All individuals were found on soft mud, sandy substratum or sandy substratum surrounded by small gravels. Grouping was observed while each group consisted of 2-7 individuals only. One individual was found with lost tail at ST that might be caused by human trampling. Since the commencement of the survey (Sep. 2012), no individual was found at TC2. It showed that TC2 was not a suitable nursery ground for horseshoes crab. In the June 2013 survey, the search records of Tachypleus tridentatus were 1.75 individuals hr-1 person-1 (mean prosomal widths: 42.94 mm) and 4.00 individuals hr-1 person-1 (34.54 mm) at TC1 and TC3, respectively. Similar to previous surveys, the highest search record of 9.83 individuals hr-1 person-1 (40.25 mm) was reported at ST.  According to Li (2008), the prosomal width of Tachypleus tridentatus recorded ranged 11.02¡Ð57.62 mm that corresponded to an estimated age of 1.7¡V6.8 years old.

5.3.12    Another less common species Carcinoscorpius rotundicauda was not found during the whole survey period except the survey conducted in December 2012 at ST (4 individuals). This species was believed present in ST at very low number while encounter was very rare.

5.3.13    An active search method was adopted for seagrass bed survey at each sampling zone. Two patches of Halophila ovalis were recorded nearby the mangrove vegetation at tidal level 2 m above C.D. at ST. The estimated total area and mean area were 299.9 m2 and 463.7 m2 respectively while the estimated coverage ranged 90-100%. Both patches were so close and formed a long seagrass strand with estimated total area 763.6 m2. One patch of Zostera japonica was found within the long strand of Halophila ovalis. The estimated area was 14.6 m2 while the estimated coverage ranged 70-90%. For seagrass Halophila ovalis, the total area and estimated coverage increased gradually. It showed that the seagrass was in scattered patches during dry season then grew and merged into single patch during wet season. For seagrass Zostera japonica, it was not reported in the surveys of September and December 2012. Seasonal recruitment of few patches was reported between December and March. Then the patch size increased and merged gradually during wet season.

5.3.14    The intertidal soft shore community surveys were conducted in low tide period on 8th (for TC3), 9th (for TC1), 12th (for TC2) and 22nd June 2013 (for ST). A total of 17329 individuals were recorded. Mollusks were significantly the most abundant phylum (total individuals 16751, density 558 individuals m-2, relative abundance 96.7%). The second abundant group was arthropod (total individuals: 416, density 14 individuals m-2, 2.4%) respectively. Relatively other phyla were very low in abundance (0.5%). Similarly, the most diverse phylum were mollusks (43 taxa) followed by arthropods (17 taxa) and annelids (14 taxa). The taxa of other phyla were relatively less (2 taxa).

5.3.15    The present survey was the third time of sampling of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project could not be detected on seagrass.  In case, abnormal phenomenon (e.g. rapid reduction of seagrass patch size) was observed, it would be reported as soon as possible.

5.3.16    There was no consistent zonation pattern of species distribution observed across sampling zones and tidal levels in Tung Chung Wan and San Tau. The species distribution should be determined by the type of substratum primarily. In general, gastropods Batillaria multiformis (6055 individuals, 35%), Cerithidea djadjariensis (3721 individuals, 21%), rock oyster Saccostrea cucullata (1829 individuals, 11%), gastropods Monodonta labio (1489 individuals, 9%) and Cerithidea cingulata (1031 individuals, 6%) were the most common occurring species among the four sampling zones.

5.3.17    The June 2013 survey results indicate that the impacts of the HKLR project could not be detected on horseshoe crabs, seagrass and intertidal soft shore community.

5.3.18    Environmental site inspection was carried out on 4, 11, 18 and 28 June 2013, 2, 9, 16, 23 and 30 July 2013, and 6, 13, 20 and 30 August 2013. Recommendations on remedial actions were given to the Contractors for the deficiencies identified during the site inspections.

5.3.19    A site inspection was undertaken by EPD on 7 June 2013 and a record of inspection was issued to the Contractor.  The Contractor was advised to repair the silt curtain provided at Portion A immediately before continuation of any filling activities and to ensure the silt curtain is fully maintained throughout the works.  The Contractor has modified the silt curtain arrangement to minimise the potential water quality impacts and provided regular maintenance for the silt curtain.

5.3.20    There was one environmental complaint received during this reporting period.

5.3.21    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 ¡§Notification of Environmental Quality Limit Exceedances

 


 

Appendix N

Cumulative Statistic on Complaints


 

 

Appendix O

Mudflat Monitoring Results