Contract No. HY/2011/03

Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road

Section between Scenic Hill and Hong Kong Boundary Crossing Facilities

 

 

 

 

 

 

Monthly EM&A Report No.36 (September 2015)

                                                                                                     

15 October 2015

 

Revision 1

 

 

 

 

 

 

 

 

 

 

 

 

Main Contractor                                                                                                                     Designer

 

 

 


 

 

Contents

Executive Summary

1...... Introduction.. 1

1.1                          Basic Project Information. 1

1.2                          Project Organisation. 2

1.3                          Construction Programme. 2

1.4                          Construction Works Undertaken During the Reporting Month. 2

2....... Air Quality Monitoring.. 4

2.1                          Monitoring Requirements. 4

2.2                          Monitoring Equipment 4

2.3                          Monitoring Locations. 4

2.4                          Monitoring Parameters, Frequency and Duration. 5

2.5                          Monitoring Methodology. 5

2.6                          Monitoring Schedule for the Reporting Month. 7

2.7                          Monitoring Results. 7

3....... Noise Monitoring.. 9

3.1                          Monitoring Requirements. 9

3.2                          Monitoring Equipment 9

3.3                          Monitoring Locations. 9

3.4                          Monitoring Parameters, Frequency and Duration. 9

3.5                          Monitoring Methodology. 10

3.6                          Monitoring Schedule for the Reporting Month. 10

3.7                          Monitoring Results. 11

4....... Water Quality Monitoring.. 12

4.1                          Monitoring Requirements. 12

4.2                          Monitoring Equipment 13

4.3                          Monitoring Parameters, Frequency and Duration. 13

4.4                          Monitoring Locations. 13

4.5                          Monitoring Methodology. 14

4.6                          Monitoring Schedule for the Reporting Month. 15

4.7                          Monitoring Results. 15

5....... Dolphin Monitoring.. 17

5.1                          Monitoring Requirements. 17

5.2                          Monitoring Methodology. 17

5.3                          Monitoring Results. 19

5.4                          Reference. 21

6....... Mudflat Monitoring.. 22

6.1                          Sedimentation Rate Monitoring. 22

6.2                          Water Quality Monitoring. 23

6.3                          Mudflat Ecology Monitoring Methodology. 24

6.4                          Event and Action Plan for Mudflat Monitoring. 25

6.5                          Mudflat Ecology Monitoring Results and Conclusion. 26

6.6                          Reference. 34

7....... Environmental Site Inspection and Audit 36

7.1                          Site Inspection. 36

7.2                          Advice on the Solid and Liquid Waste Management Status. 39

7.3                          Environmental Licenses and Permits. 39

7.4                          Implementation Status of Environmental Mitigation Measures. 39

7.5                          Summary of Exceedances of the Environmental Quality Performance Limit 39

7.6                          Summary of Complaints, Notification of Summons and Successful Prosecution. 40

8....... Future Key Issues. 41

8.1                          Construction Programme for the Coming Months. 41

8.2                          Environmental Monitoring Schedule for the Coming Month. 42

9....... Conclusions. 43

9.1                          Conclusions. 43

 

 

Figures

 

Figure 1.1        Location of the Site

Figure 2.1         Environmental Monitoring Stations

Figure 6.1         Mudflat Survey Area

 

                           

Appendices

Appendix A        Environmental Management Structure

Appendix B       Construction Programme

Appendix C       Calibration Certificates

Appendix D       Monitoring Schedule

Appendix E       Monitoring Data and Graphical Plots

Appendix F       Event and Action Plan

Appendix G       Wind Data

Appendix H       Dolphin Monitoring Results

Appendix I         Mudflat Monitoring Results

Appendix J        Waste Flow Table

Appendix K       Cumulative Statistics on Complaints

Appendix L        Environmental Licenses and Permits  

Appendix M     Implementation Schedule of Environmental Mitigation Measures  

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

Appendix O       Location of Works Areas


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/D for HKLR and EP-353/2009/I for HKBCF were issued on 22 December 2014 and 17 July 2015, respectively. These documents are available through the EIA Ordinance Register. The construction phase of Contract was commenced on 17 October 2012.

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

This is the thirty-sixth Monthly 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 to 30 September 2015.

Environmental Monitoring and Audit Progress

The monthly EM&A programme was undertaken in accordance with the Updated EM&A Manual for HKLR (Version 1.0).  A summary of the monitoring activities during this reporting month is listed below:

1-hr TSP Monitoring

2, 8, 14, 18, 24 and 30 September 2015

24-hr TSP Monitoring

1, 7, 11, 17, 23 and 29 September 2015

Noise Monitoring

4, 8, 14, 24 and 30 September 2015

Water Quality Monitoring

2, 4, 7, 9, 11, 14, 16, 18, 21, 23, 25, 28 and 30 September 2015

Chinese White Dolphin Monitoring

2, 11, 17 and 29 September 2015

Mudflat Monitoring (Sedimentation Rate)

10 September 2015

Mudflat Monitoring (Ecology)

5, 6, 10, 12 and 13 September 2015

Site Inspection

2, 9, 16, 25 and 30 September 2015

Due to bad weather condition on 2 Sep 2015, noise monitoring at NMS5 was rescheduled from 2 Sep 2015 to 4 Sep 2015.

Due to boat availability issue, the dolphin monitoring schedule was rescheduled from 15 Sep 2015 to 17 Sep 2015 and from 21 Sep 2015 to 29 Sep 2015.

Breaches of Action and Limit Levels                                                                              

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

Environmental Monitoring

Parameters

Action Level (AL)

Limit Level (LL)

Air Quality

1-hr TSP

0

0

24-hr TSP

0

0

Noise

Leq (30 min)

0

0

Water Quality

Suspended solids level (SS)

1

0

Turbidity level

0

0

Dissolved oxygen level (DO)

0

0

One Action Level exceedances of suspended solid level were recorded during the reporting month.

Complaint Log       

There were no complaints received in relation to the environmental impacts during the reporting period.  However, EPD informed SOR and IEC that there was an enquiry regarding untreated wastewater discharge on 29 September 2015 via email.  An investigation is being undertaken and investigation report will be sent to EPD for record.   

Notifications of Summons and Prosecutions

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

Reporting Changes

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

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

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

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

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

Future Key Issues

The future key issues include potential noise, air quality, water quality and ecological impacts and waste management arising from the following construction activities to be undertaken in the upcoming month:

  • Dismantling/trimming of Temporary 40mm Stone Platform for Construction of Seawall at Portion X;
  • Filling Works behind Stone Platform at Portion X;
  • Construction of Seawall at Portion X;
  • Loading and Unloading Filling Material at Portion X;
  • Pipe Piling at Portion X;
  • Band Drains Installation at Portion X;
  • Excavation and Lateral Support Works at Scenic Hill Tunnel (Cut & Cover Tunnel) at Portion X;
  • Laying Blinding Layer for Tunnel Box Structure at Scenic Hill Tunnel (Cut & Cover Tunnel) at Portion X;
  • Construction of Tunnel Box Structure at Scenic Hill Tunnel (Cut & Cover Tunnel) at Portion X
  • Socket H-Piling work at Scenic Hill Tunnel (Cut & Cover Tunnel) at Portion X;
  • Construction of Sheet Pile at Scenic Hill Tunnel (Cut & Cover Tunnel) at Portion X;
  • Excavation Works for HKBCF to Airport Tunnel at Portion X;
  • Sheet Piling Works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel) at Portion X;
  • Socket H-Piling Works for HKBCF to Airport Tunnel East (Cut &Cover Tunnel) at Portion X;
  • Pipe Piling Works for HKBCF to Airport Tunnel East (Cut &Cover Tunnel) at Portion X;
  • Works for Diversion of Airport Road;
  • Utilities Detection at Airport Road / Airport Express Line/ East Coast Road;
  • Establishment of Site Access at Airport Road / Airport Express Line/East Coast Road;
  • Canopy Pipe Drilling / Mined Tunnel Excavation / Box Jacking underneath Airport Road and Airport Express Line;
  • Excavation and Lateral Support Works at shaft 3 extension north shaft & south shaft at Kwo Lo Wan Road;
  • Excavation and Lateral Support Works for HKBCF to Airport Tunnel West (Cut & Cover Tunnel) at Airport Road;
  • Utility Culvert Excavation at Portion Y;
  • Highway Operation and Maintenance Area Building Foundation & Sub-structure Works at Portion Y;
  • Excavation for Scenic Hill Tunnel at West Portal; and
  • Ventilation Building Foundation and Superstructure Works at West Portal.

 


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/D for HKLR and EP-353/2009/I for HKBCF were issued on 22 December 2014 and 17 July 2015, respectively. These documents are available through the EIA Ordinance Register. The construction phase of Contract was commenced on 17 October 2012.  Figure 1.1 shows the project site boundary. The works areas are shown in Appendix O.

1.1.4       The Contract includes the following key aspects:

¡P                    New reclamation along the east coast of the approximately 23 hectares.

¡P                    Tunnel of Scenic Hill (Tunnel SHT) from Scenic Hill to the new reclamation, of approximately 1km in length with three (3) lanes for the east bound carriageway heading to the HKBCF and four (4) lanes for the westbound carriageway heading to the HZMB Main Bridge.

¡P                    An abutment of the viaduct portion of the HKLR at the west portal of Tunnel SHT and associated road works at the west portal of Tunnel SHT.

¡P                    An at grade road on the new reclamation along the east coast of the HKIA to connect with the HKBCF, of approximately 1.6 km along dual 3-lane carriageway with hard shoulder for each bound.

¡P                    Road links between the HKBCF and the HKIA including new roads and the modification of existing roads at the HKIA, involving viaducts, at grade roads and a Tunnel HAT.

¡P                    A highway operation and maintenance area (HMA) located on the new reclamation, south of the Dragonair Headquarters Building, including the construction of buildings, connection roads and other associated facilities.

¡P                    Associated civil, structural, building, geotechnical, marine, environmental protection, landscaping, drainage and sewerage, tunnel and highway electrical and mechanical works, together with the installation of street lightings, traffic aids and sign gantries, water mains and fire hydrants, provision of facilities for installation of traffic control and surveillance system (TCSS), reprovisioning works of affected existing facilities, implementation of transplanting, compensatory planting and protection of existing trees, and implementation of an environmental monitoring and audit (EM&A) program.

1.1.5       This is the thirty-sixth Monthly EM&A report for the Contract which summarizes the monitoring results and audit findings of the EM&A programme during the reporting period from 1 to 30 September 2015.

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

1.2.1       The project organization structure and lines of communication with respect to the on-site environmental management structure is shown in Appendix A.  The key personnel contact names and numbers are summarized in Table 1.1. 

Table 1.1          Contact Information of Key Personnel

Party

Position

Name

Telephone

Fax

Supervising Officer¡¦s Representative
(Ove Arup & Partners
Hong Kong Limited)

(Chief Resident Engineer, CRE)

Robert Antony Evans

3968 0801

2109 1882

Environmental Project Office / Independent Environmental Checker
(Ramboll Environ Hong Kong Limited)

Environmental Project Office Leader

Y. H. Hui

3465 2888

3465 2899

Independent Environmental Checker

Antony Wong

3465 2888

3465 2899

Contractor
(China State Construction Engineering (Hong Kong) Ltd)

Project Manager

S. Y. Tse

3968 7002

2109 2588

Environmental Officer

Federick Wong

3968 7117

2109 2588

Environmental Team
(BMT Asia Pacific)

Environmental Team Leader

Claudine Lee

2241 9847

2815 3377

24 hours complaint hotline

---

---

5699 5730

---

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 Month

1.4.1       A summary of the construction activities undertaken during this reporting month is shown in Table 1.2.


 

Table 1.2          Construction Activities During Reporting Month

Description of Activities

Site Area

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

Portion X

Filling works behind stone platform

Portion X

Construction of seawall

Portion X

Loading and unloading of filling materials

Portion X

Band drains installation

Portion X

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

Portion X

Socket H-Piling work for Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Laying blinding layer for tunnel box structure at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Construction of Sheet Pile at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

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

Portion X

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

Portion X

Excavation for HKBCF to Airport Tunnel

Portion X

Excavation for Scenic Hill Tunnel

West Portal

Ventilation building foundation and superstructure works

West Portal

Works for diversion of Airport Road

Airport Road

Utilities detection

Airport Road/ Airport Express Line/ East Coast Road

Establishment of Site Access

Airport Road/ Airport Express Line/ East Coast Road

Canopy pipe drilling underneath Airport Express Line

Airport Express Line

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

Kwo Lo Wan Road

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

Airport Road

Utility culvert excavation

Portion Y

Highway Operation and Maintenance Area Building foundation & sub-structure works

Portion Y

 


 

2        Air Quality Monitoring

2.1                Monitoring Requirements

2.1.1       In accordance with the Contract Specific EM&A Manual, baseline 1-hour and 24-hour TSP levels at two air quality monitoring stations were established.  Impact 1-hour TSP monitoring was conducted for at least three times every 6 days, while impact 24-hour TSP monitoring was carried out for at least once every 6 days. The Action and Limit Level for 1-hr TSP and 24-hr TSP are provided in Table 2.1 and Table 2.2, respectively.

Table 2.1          Action and Limit Levels for 1-hour TSP

Monitoring Station

Action Level, µg/m3

Limit Level, µg/m3

AMS 5 ¡V Ma Wan Chung Village (Tung Chung)

352

500

AMS 6 ¡V Dragonair / CNAC (Group) Building (HKIA)

360

 

Table 2.2         Action and Limit Levels for 24-hour TSP

Monitoring Station

Action Level, µg/m3

Limit Level, µg/m3

AMS 5 ¡V Ma Wan Chung Village (Tung Chung)

164

260

AMS 6 ¡V Dragonair / CNAC (Group) Building (HKIA)

173

260

 

2.2.1       24-hour TSP air quality monitoring was performed using High Volume Sampler (HVS) located at each designated monitoring station. The HVS meets all the requirements of the Contract Specific EM&A Manual.  Portable direct reading dust meters were used to carry out the 1-hour TSP monitoring.  Brand and model of the equipment is given in Table 2.3.

Table 2.3          Air Quality Monitoring Equipment

Equipment

Brand and Model

Portable direct reading dust meter (1-hour TSP)

Sibata Digital Dust Monitor (Model No. LD-3B)

High Volume Sampler
(24-hour TSP)

Tisch Environmental Mass Flow Controlled Total Suspended Particulate (TSP) High Volume Air Sampler (Model No. TE-5170)

2.3.1       Monitoring locations AMS5 and AMS6 were set up at the proposed locations in accordance with Contract Specific EM&A Manual.

2.3.2       Figure 2.1 shows the locations of monitoring stations. Table 2.4 describes the details of the monitoring stations.

Table 2.4          Locations of Impact Air Quality Monitoring Stations

Monitoring Station

Location

AMS5

Ma Wan Chung Village (Tung Chung)

AMS6

Dragonair / CNAC (Group) Building (HKIA)

2.4.1       Table 2.5 summarizes the monitoring parameters, frequency and duration of impact TSP monitoring.

Table 2.5          Air Quality Monitoring Parameters, Frequency and Duration

Parameter

Frequency and Duration

1-hour TSP

Three times every 6 days while the highest dust impact was expected

24-hour TSP

Once every 6 days

 

2.5.1       24-hour TSP Monitoring

(a)           The HVS was installed in the vicinity of the air sensitive receivers. The following criteria were considered in the installation of the HVS.

(i)         A horizontal platform with appropriate support to secure the sampler against gusty wind was provided.

(ii)         The distance between the HVS and any obstacles, such as buildings, was at least twice the height that the obstacle protrudes above the HVS.

(iii)        A minimum of 2 meters separation from walls, parapets and penthouse for rooftop sampler was provided.

(iv)        No furnace or incinerator flues are nearby.

(v)         Airflow around the sampler was unrestricted.

(vi)        Permission was obtained to set up the samplers and access to the monitoring stations.

(vii)       A secured supply of electricity was obtained to operate the samplers.

(viii)       The sampler was located more than 20 meters from any dripline.

(ix)        Any wire fence and gate, required to protect the sampler, did not obstruct the monitoring process.

(x)        Flow control accuracy was kept within ¡Ó2.5% deviation over 24-hour sampling period.

(b)          Preparation of Filter Papers

(i)         Glass fibre filters, G810 were labelled and sufficient filters that were clean and without pinholes were selected.

(ii)        All filters were equilibrated in the conditioning environment for 24 hours before weighing. The conditioning environment temperature was around 25 ¢XC and not variable by more than ¡Ó3 ¢XC; the relative humidity (RH) was < 50% and not variable by more than ¡Ó5%.  A convenient working RH was 40%.

(iii)       All filter papers were prepared and analysed by ALS Technichem (HK) Pty Ltd., which is a HOKLAS accredited laboratory and has comprehensive quality assurance and quality control programmes.

(c)          Field Monitoring

(i)         The power supply was checked to ensure the HVS works properly.

(ii)         The filter holder and the area surrounding the filter were cleaned.

(iii)        The filter holder was removed by loosening the four bolts and a new filter, with stamped number upward, on a supporting screen was aligned carefully.

(iv)        The filter was properly aligned on the screen so that the gasket formed an airtight seal on the outer edges of the filter.

(v)        The swing bolts were fastened to hold the filter holder down to the frame.  The pressure applied was sufficient to avoid air leakage at the edges.

(vi)        Then the shelter lid was closed and was secured with the aluminium strip.

(vii)       The HVS was warmed-up for about 5 minutes to establish run-temperature conditions.

(viii)       A new flow rate record sheet was set into the flow recorder.

(ix)       On site temperature and atmospheric pressure readings were taken and the flow rate of the HVS was checked and adjusted at around 1.1 m3/min, and complied with the range specified in the Updated EM&A Manual for HKLR (Version 1.0) (i.e. 0.6-1.7 m3/min).

(x)        The programmable digital timer was set for a sampling period of 24 hours, and the starting time, weather condition and the filter number were recorded.

(xi)        The initial elapsed time was recorded.

(xii)       At the end of sampling, on site temperature and atmospheric pressure readings were taken and the final flow rate of the HVS was checked and recorded.

(xiii)      The final elapsed time was recorded.

(xiv)      The sampled filter was removed carefully and folded in half length so that only surfaces with collected particulate matter were in contact.

(xv)       It was then placed in a clean plastic envelope and sealed.

(xvi)      All monitoring information was recorded on a standard data sheet.

(xvii)      Filters were then sent to ALS Technichem (HK) Pty Ltd. for analysis.

(d)          Maintenance and Calibration

(i)         The HVS and its accessories were maintained in good working condition, such as replacing motor brushes routinely and checking electrical wiring to ensure a continuous power supply.

(ii)         5-point calibration of the HVS was conducted using TE-5025A Calibration Kit prior to the commencement of baseline monitoring. Bi-monthly 5-point calibration of the HVS will be carried out during impact monitoring.

(iii)        Calibration certificate of the HVSs are provided in Appendix C.

2.5.2       1-hour TSP Monitoring

(a)        Measuring Procedures

The measuring procedures of the 1-hour dust meter were in accordance with the Manufacturer¡¦s Instruction Manual as follows:-

(i)                   Turn the power on.

(ii)        Close the air collecting opening cover.

(iii)       Push the ¡§TIME SETTING¡¨ switch to [BG].

(iv)        Push ¡§START/STOP¡¨ switch to perform background measurement for 6 seconds.

(v)        Turn the knob at SENSI ADJ position to insert the light scattering plate.

(vi)        Leave the equipment for 1 minute upon ¡§SPAN CHECK¡¨ is indicated in the display.

(vii)       Push ¡§START/STOP¡¨ switch to perform automatic sensitivity adjustment. This measurement takes 1 minute.

(viii)      Pull out the knob and return it to MEASURE position.

(ix)       Push the ¡§TIME SETTING¡¨ switch the time set in the display to 3 hours.

(x)        Lower down the air collection opening cover.

(xi)       Push ¡§START/STOP¡¨ switch to start measurement.

(b)           Maintenance and Calibration

(i)         The 1-hour TSP meter was calibrated at 1-year intervals against a Tisch Environmental Mass Flow Controlled Total Suspended Particulate (TSP) High Volume Air Sampler. Calibration certificates of the Laser Dust Monitors are provided in Appendix C.

2.6.1       The schedule for air quality monitoring October 2015 is provided in Appendix D.

2.7                Monitoring Results

2.7.1       The monitoring results for 1-hour TSP and 24-hour TSP are summarized in Tables 2.6 and 2.7 respectively. Detailed impact air quality monitoring results and relevant graphical plots are presented in Appendix E.

Table 2.6         Summary of 1-hour TSP Monitoring Results During the Reporting Month

Monitoring Station

Average (mg/m3)

Range (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

AMS5

95

58 - 151

352

500

AMS6

97

66 - 138

360

500

 

 

 

 

 

 

Table 2.7         Summary of 24-hour TSP Monitoring Results During the Reporting Month

Monitoring Station

Average (mg/m3)

Range (mg/m3)

Action Level  (mg/m3)

Limit Level (mg/m3)

AMS5

36

18 - 77

164

260

AMS6

61

34 - 119

173

260

 

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

2.7.3       The event action plan is annexed in Appendix F.

2.7.4       The wind data obtained from the on-site weather station during the reporting month is shown in Appendix G.


 

3.1.1       In accordance with the Contract Specific EM&A Manual, impact noise monitoring was conducted for at least once per week during the construction phase of the Project. The Action and Limit level of the noise monitoring is provided in Table 3.1.

Table 3.1          Action and Limit Levels for Noise during Construction Period

Monitoring Station

Time Period

Action Level

Limit Level

NMS5 ¡V Ma Wan Chung Village (Ma Wan Chung Resident Association) (Tung Chung)

0700-1900 hours on normal weekdays

When one documented complaint is received

75 dB(A)

3.2                Monitoring Equipment

3.2.1       Noise monitoring was performed using sound level meters at each designated monitoring station.  The sound level meters deployed comply with the International Electrotechnical Commission Publications (IEC) 651:1979 (Type 1) and 804:1985 (Type 1) specifications.  Acoustic calibrator was deployed to check the sound level meters at a known sound pressure level.  Brand and model of the equipment are given in Table 3.2.

Table 3.2         Noise Monitoring Equipment

Equipment

Brand and Model

Integrated Sound Level Meter

B&K 2238

Acoustic Calibrator

B&K 4231

3.3                Monitoring Locations

3.3.1       Monitoring location NMS5 was set up at the proposed locations in accordance with Contract Specific EM&A Manual.

3.3.2       Figure 2.1 shows the locations of monitoring stations. Table 3.3 describes the details of the monitoring stations.

Table 3.3          Locations of Impact Noise Monitoring Stations

Monitoring Station

Location

NMS5

Ma Wan Chung Village (Ma Wan Chung Resident Association) (Tung Chung)

3.4.1       Table 3.4 summarizes the monitoring parameters, frequency and duration of impact noise monitoring.


 

Table 3.4         Noise Monitoring Parameters, Frequency and Duration

Parameter

Frequency and Duration

30-mins measurement at each monitoring station between 0700 and 1900 on normal weekdays (Monday to Saturday). Leq, L10 and L90 would be recorded.

At least once per week

 

3.5.1       Monitoring Procedure

(a)        The sound level meter was set on a tripod at a height of 1.2 m above the podium for free-field measurements at NMS5. A correction of +3 dB(A) shall be made to the free field measurements.

(b)        The battery condition was checked to ensure the correct functioning of the meter.

(c)        Parameters such as frequency weighting, the time weighting and the measurement time were set as follows:-

(i)            frequency weighting: A

(ii)           time weighting: Fast

(iii)          time measurement: Leq(30-minutes) during non-restricted hours i.e. 07:00 ¡V 1900 on normal weekdays

(e)        Prior to and after each noise measurement, the meter was calibrated using the acoustic calibrator for 94.0 dB(A) at 1000 Hz.  If the difference in the calibration level before and after measurement was more than 1.0 dB(A), the measurement would be considered invalid and repeat of noise measurement would be required after re-calibration or repair of the equipment.

(f)         During the monitoring period, the Leq, L10 and L90 were recorded.  In addition, site conditions and noise sources were recorded on a standard record sheet.

(g)        Noise measurement was paused during periods of high intrusive noise (e.g. dog barking, helicopter noise) if possible. Observations were recorded when intrusive noise was unavoidable.

(h)        Noise monitoring was cancelled in the presence of fog, rain, wind with a steady speed exceeding 5m/s, or wind with gusts exceeding 10m/s. The wind speed shall be checked with a portable wind speed meter capable of measuring the wind speed in m/s.

3.5.2       Maintenance and Calibration

(a)          The microphone head of the sound level meter was cleaned with soft cloth at regular intervals.

(b)           The meter and calibrator were sent to the supplier or HOKLAS laboratory to check and calibrate at yearly intervals.

(c)        Calibration certificates of the sound level meters and acoustic calibrators are provided in Appendix C.

3.6.1       The schedule for construction noise monitoring in October 2015 is provided in Appendix D.


 

3.7                Monitoring Results

3.7.1       The monitoring results for construction noise are summarized in Table 3.5 and the monitoring results and relevant graphical plots are provided in Appendix E.  

Table 3.5          Summary of Construction Noise Monitoring Results During the Reporting Month

Monitoring Station

Average Leq (30 mins), dB(A)

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

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

NMS5

56

55 ¡V 58

75

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

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

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

3.7.4       The event action plan is annexed in Appendix F.


4        Water Quality Monitoring

4.1.1       Impact water quality monitoring was carried out to ensure that any deterioration of water quality is detected, and that timely action is taken to rectify the situation.  For impact water quality monitoring, measurements were taken in accordance with the Contract Specific EM&A Manual. Table 4.1 shows the established Action/Limit Levels for the environmental monitoring works.  The ET proposed to amend the Acton Level and Limit Level for turbidity and suspended solid and EPD approved ET¡¦s proposal on 25 March 2013.  Therefore, Action Level and Limit Level for the Contract have been changed since 25 March 2013.

4.1.2       The original and revised Action Level and Limit Level for turbidity and suspended solid are shown in Table 4.1.

Table 4.1          Action and Limit Levels for Water Quality

Parameter (unit)

Water Depth

Action Level

Limit Level

Dissolved Oxygen (mg/L) (surface, middle and bottom)

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.

4.2.1       Table 4.2 summarises the equipment used in the impact water quality monitoring programme.

Table 4.2          Water Quality Monitoring Equipment

Equipment      

Brand and Model

DO and Temperature Meter, Salinity Meter, Turbidimeter and pH Meter

YSI Model 6820 V2-M, 650

Positioning Equipment

DGPS ¡V KODEN : KGP913MkII, KBG3

Water Depth Detector

Layin Associates: SM-5 & SM5A

Water Sampler

Wildlife Supply Company : 5487-10

4.3.1       Table 4.3 summarises the monitoring parameters, frequency and monitoring depths of impact water quality monitoring as required in the Contract Specific EM&A Manual.

Table 4.3          Impact Water Quality Monitoring Parameters and Frequency

Monitoring Stations

Parameter, unit

Frequency

No. of depth

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

 

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

 

Sensitive Receiver Stations:
SR3, SR4, SR
5, SR10A & SR10B

¡P    Depth, m

¡P    Temperature, oC

¡P    Salinity, ppt

¡P    Dissolved Oxygen (DO), mg/L

¡P    DO Saturation, %

¡P    Turbidity, NTU

¡P    pH

¡P   Suspended Solids (SS), mg/L

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).

 

4.4.1       In accordance with the Contract Specific EM&A Manual, thirteen stations (6 Impact Stations, 5 Sensitive Receiver Stations and 2 Control Stations) were designated for impact water quality monitoring.  The six Impact Stations (IS) were chosen on the basis of their proximity to the reclamation and thus the greatest potential for water quality impacts, the five Sensitive Receiver Stations (SR) were chosen as they are close to the key sensitive receives and the two Control Stations (CS) were chosen to facilitate comparison of the water quality of the IS stations with less influence by the Project/ ambient water quality conditions.

4.4.2       The locations of these monitoring stations are summarized in Table 4.4 and shown in
Figure 2.
1.

Table 4.4         Impact Water Quality Monitoring Stations

Monitoring Stations

Description

Coordinates

Easting

Northing

IS5

Impact Station (Close to HKLR construction site)

811579

817106

IS(Mf)6

Impact Station (Close to HKLR construction site)

812101

817873

IS7

Impact Station (Close to HKBCF construction site)

812244

818777

IS8

Impact Station (Close to HKBCF construction site)

814251

818412

IS(Mf)9

Impact Station (Close to HKBCF construction site)

813273

818850

IS10

Impact Station (Close to HKBCF construction site)

812577

820670

SR3

Sensitive receivers (San Tau SSSI)

810525

816456

SR4

Sensitive receivers (Tai Ho Inlet)

814760

817867

SR5

Sensitive receivers (Artificial Reef In NE Airport)

811489

820455

SR10A

Sensitive receivers (Ma Wan Fish Culture Zone)

823741

823495

SR10B

Sensitive receivers (Ma Wan Fish Culture Zone)

823686

823213

CS2

Control Station (Mid-Ebb)

805849

818780

CS(Mf)5

Control Station (Mid-Flood)

817990

821129

4.5                Monitoring Methodology

4.5.1       Instrumentation

(a)        The in-situ water quality parameters including dissolved oxygen, temperature, salinity and turbidity, pH were measured by multi-parameter meters.

4.5.2       Operating/Analytical Procedures

(a)        Digital Differential Global Positioning Systems (DGPS) were used to ensure that the correct location was selected prior to sample collection.

(b)        Portable, battery-operated echo sounders were used for the determination of water depth at each designated monitoring station.

(c)        All in-situ measurements were taken at 3 water depths, 1 m below water surface, mid-depth and 1 m above sea bed, except where the water depth was less than 6 m, in which case the mid-depth station was omitted. Should the water depth be less than 3 m, only the mid-depth station was monitored.

(d)        At each measurement/sampling depth, two consecutive in-situ monitoring (DO concentration and saturation, temperature, turbidity, pH, salinity) and water sample for SS. The probes were retrieved out of the water after the first measurement and then re-deployed for the second measurement. Where the difference in the value between the first and second readings of DO or turbidity parameters was more than 25% of the value of the first reading, the reading was discarded and further readings were taken.

(e)        Duplicate samples from each independent sampling event were collected for SS measurement. Water samples were collected using the water samplers and the samples were stored in high-density polythene bottles. Water samples collected were well-mixed in the water sampler prior to pre-rinsing and transferring to sample bottles. Sample bottles were pre-rinsed with the same water samples. The sample bottles were then be packed in cool-boxes (cooled at 4oC without being frozen), and delivered to ALS Technichem (HK) Pty Ltd. for the analysis of suspended solids concentrations. The laboratory determination work would be started within 24 hours after collection of the water samples. ALS Technichem (HK) Pty Ltd. is a HOKLAS accredited laboratory and has comprehensive quality assurance and quality control programmes.

(f)         The analysis method and detection limit for SS is shown in Table 4.5.

Table 4.5    Laboratory Analysis for Suspended Solids

Parameters

Instrumentation

Analytical Method

Detection Limit

Suspended Solid (SS)

Weighting

APHA 2540-D

0.5mg/L

 

(g)        Other relevant data were recorded, including monitoring location / position, time, water depth, tidal stages, weather conditions and any special phenomena or work underway at the construction site in the field log sheet for information.

4.5.3       Maintenance and Calibrations

(a)        All in situ monitoring instruments would be calibrated by ALS Technichem (HK) Pty Ltd. before use and at 3-monthly intervals throughout all stages of the water quality monitoring programme. The procedures of performance check of sonde and testing results are provided in Appendix C.

4.6.1       The schedule for impact water quality monitoring in October 2015 is provided in Appendix D.

4.7                Monitoring Results

4.7.1       Impact water quality monitoring was conducted at all designated monitoring stations during the reporting month. Impact water quality monitoring results and relevant graphical plots are provided in Appendix E.

4.7.2       Number of exceedances recorded during the reporting month at each impact station are summarised in Table 4.6.

Table 4.6          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

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS(Mf)6

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS7

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS8

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS(Mf)9

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

IS10

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

SR3

Action Level

--

--

--

--

--

--

--

--

0

0

Limit Level

--

--

--

--

--

--

--

--

0

0

SR4

Action Level

--

--

--

--

--

--

--

11 Sep 2015

0

0

Limit Level

--

--

--

--

--

--

--

--

0

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

--

--

--

--

--

--

--

--

0

0

Total

Action

0

0

0

0

0

0

0

1

1**

Limit

0

0

0

0

0

0

0

0

0**

 

Notes:

S: Surface;

M: Mid-depth;

**   The total number of exceedances

 

4.7.1       For marine water quality monitoring, one Action Level exceedances of suspended solid level were recorded during the reporting month. No Limit Level exceedance of suspended solid level was recorded. No Action Level/ Limit Level exceedance of turbidity level and dissolved oxygen level were recorded during the reporting month.

4.7.2       The construction activities on 11 September 2015 were carried out within silt curtain as recommended in the EIA Report. There were no specific activities recorded during the monitoring period that would cause any significant impacts on the monitoring results. The exceedance of suspended solid level was considered to be attributed to other external factors, rather than the contract works. Therefore, the exceedance was considered as non-contract related. Record of ¡§Notification of Environmental Quality Limit Exceedances¡¨ is provided in Appendix N.

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

4.7.2       The event action plan is annexed in Appendix F.


 

 

5.1.1       Impact dolphin monitoring is required to be conducted by a qualified dolphin specialist team to evaluate whether there have been any effects on the dolphins.

5.1.2       The Action Level and Limit Level for dolphin monitoring are shown in Table 5.1.

Table 5.1          Action and Limit Levels for Dolphin Monitoring

 

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 encounter rate of number of dolphin sightings.

2.      ANI means quarterly 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.

5.1.3       The revised Event and Action Plan for dolphin Monitoring was approved by EPD in 6 May 2013. The revised Event and Action Plan is annexed in Appendix F.

Vessel-based Line-transect Survey

5.2.1       According to the requirements of the Updated EM&A Manual for HKLR (Version 1.0), dolphin monitoring programme should cover all transect lines in NEL and NWL survey areas (see Figure 1 of Appendix H) twice per month. The co-ordinates of all transect lines are shown in Table 5.2.  The coordinates of several starting points have been revised due to the obstruction of the permanent structures associated with the construction works of HKLR and the southern viaduct of TM-CLKL, as well as provision of adequate buffer distance from the Airport Restricted Areas.  The EPD issued a memo and confirmed that they had no objection on the revised transect lines on 19 August 2015, and the revised coordinates are in red and marked with an asterisk in Table 5.2.

Table 5.2          Co-ordinates of Transect Lines

Line No.

Easting

Northing

 

Line No.

Easting

Northing

1

Start Point

804671

815456*

 

13

Start Point

816506

819480

1

End Point

804671

831404

 

13

End Point

816506

824859

2

Start Point

805475

815913*

 

14

Start Point

817537

820220

2

End Point

805477

826654

 

14

End Point

817537

824613

3

Start Point

806464

819435

 

15

Start Point

818568

820735

3

End Point

806464

822911

 

15

End Point

818568

824433

4

Start Point

807518

819771

 

16

Start Point

819532

821420

4

End Point

807518

829230

 

16

End Point

819532

824209

5

Start Point

808504

820220

 

17

Start Point

820451

822125

5

End Point

808504

828602

 

17

End Point

820451

823671

6

Start Point

809490

820466

 

18

Start Point

821504

822371

6

End Point

809490

825352

 

18

End Point

821504

823761

7

Start Point

810499

820880*

 

19

Start Point

822513

823268

7

End Point

810499

824613

 

19

End Point

822513

824321

8

Start Point

811508

821123*

 

20

Start Point

823477

823402

8

End Point

811508

824254

 

20

End Point

823477

824613

9

Start Point

812516

821303*

 

21

Start Point

805476

827081

9

End Point

812516

824254

 

21

End Point

805476

830562

10

Start Point

813525

820872

 

22

Start Point

806464

824033

10

End Point

813525

824657

 

22

End Point

806464

829598

11

Start Point

814556

818853*

 

23

Start Point

814559

821739

11

End Point

814556

820992

 

23

End Point

814559

824768

12

Start Point

815542

818807

 

 

 

 

 

12

End Point

815542

824882

 

 

 

 

 

Note:
Co-ordinates in red and marked with asterisk are revised co-ordinates of transect line. 

 

5.2.2       The survey team used standard line-transect methods (Buckland et al. 2001) to conduct the systematic vessel surveys, and followed the same technique of data collection that has been adopted over the last 16 years of marine mammal monitoring surveys in Hong Kong developed by HKCRP (see Hung 2012, 2013).  For each monitoring vessel survey, a 15-m inboard vessel with an open upper deck (about 4.5 m above water surface) was used to make observations from the flying bridge area.

5.2.3       Two experienced observers (a data recorder and a primary observer) made up the on-effort survey team, and the survey vessel transited different transect lines at a constant speed of 13-15 km per hour.  The data recorder searched with unaided eyes and filled out the datasheets, while the primary observer searched for dolphins and porpoises continuously through 7 x 50 Fujinon marine binoculars.  Both observers searched the sea ahead of the vessel, between 270o and 90o (in relation to the bow, which is defined as 0o).  One to two additional experienced observers were available on the boat to work in shift (i.e. rotate every 30 minutes) in order to minimize fatigue of the survey team members.  All observers were experienced in small cetacean survey techniques and identifying local cetacean species.

5.2.4       During on-effort survey periods, the survey team recorded effort data including time, position (latitude and longitude), weather conditions (Beaufort sea state and visibility), and distance travelled in each series (a continuous period of search effort) with the assistance of a handheld GPS (Garmin eTrex Legend).

5.2.5       Data including time, position and vessel speed were also automatically and continuously logged by handheld GPS throughout the entire survey for subsequent review.

5.2.6       When dolphins were sighted, the survey team would end the survey effort, and immediately record the initial sighting distance and angle of the dolphin group from the survey vessel, as well as the sighting time and position.  Then the research vessel was diverted from its course to approach the animals for species identification, group size estimation, assessment of group composition, and behavioural observations.  The perpendicular distance (PSD) of the dolphin group to the transect line was later calculated from the initial sighting distance and angle.

5.2.7       Survey effort being conducted along the parallel transect lines that were perpendicular to the coastlines (as indicated in Figure 1 of Appendix H) was labeled as ¡§primary¡¨ survey effort, while the survey effort conducted along the connecting lines between parallel lines was labeled as ¡§secondary¡¨ survey effort.  According to HKCRP long-term dolphin monitoring data, encounter rates of Chinese white dolphins deduced from effort and sighting data collected along primary and secondary lines were similar in NEL and NWL survey areas.  Therefore, both primary and secondary survey effort were presented as on-effort survey effort in this report.

5.2.8       Encounter rates of Chinese White Dolphins (number of on-effort sightings per 100 km of survey effort and number of dolphins from all on-effort sightings 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.  Only data collected under Beaufort 3 or below condition would be used for encounter rate analysis.  Dolphin encounter rates were calculated using primary survey effort alone, as well as the combined survey effort from both primary and secondary lines.

Photo-identification Work

5.2.9       When a group of Chinese White Dolphins were sighted during the line-transect survey, the survey team would end effort and approach the group slowly from the side and behind to take photographs of them.  Every attempt was made to photograph every dolphin in the group, and even photograph both sides of the dolphins, since the colouration and markings on both sides may not be symmetrical.

5.2.10    A professional digital cameras (Canon EOS 7D and 60D models), equipped with long telephoto lenses (100-400 mm zoom), were available on board for researchers to take sharp, close-up photographs of dolphins as they surfaced.  The images were shot at the highest available resolution and stored on Compact Flash memory cards for downloading onto a computer.

5.2.11    All digital images taken in the field were first examined, and those containing potentially identifiable individuals were sorted out.  These photographs would then be examined in greater detail, and were carefully compared to the existing Chinese White Dolphin photo-identification catalogue maintained by HKCRP since 1995.

5.2.12    Chinese White Dolphins can be identified by their natural markings, such as nicks, cuts, scars and deformities on their dorsal fin and body, and their unique spotting patterns were also used as secondary identifying features (Jefferson 2000).

5.2.13    All photographs of each individual were then compiled and arranged in chronological order, with data including the date and location first identified (initial sighting), re-sightings, associated dolphins, distinctive features, and age classes entered into a computer database.  Detailed information on all identified individuals will be further presented as an appendix in quarterly EM&A reports.

Vessel-based Line-transect Survey

5.3.1       During the month of September 2015, two sets of systematic line-transect vessel surveys were conducted on 2nd, 11th, 17th and 29th to cover all transect lines in NWL and NEL survey areas twice. The survey routes of each survey day are presented in Figures 2 to 5 of Appendix H. 

5.3.2       From these surveys, a total of 303.46 km of survey effort was collected, with 99.0% of the total survey effort being conducted under favourable weather conditions (i.e. Beaufort Sea State 3 or below with good visibility) (Annex I of Appendix H). Among the two areas, 115.34 km and 188.12 km of survey effort were collected from NEL and NWL survey areas respectively.  Moreover, the total survey effort conducted on primary lines was 221.51 km, while the effort on secondary lines was 81.95 km.

5.3.3       During the two sets of monitoring surveys in September 2015, seven groups of 54 Chinese White Dolphins were sighted. (Annex II of Appendix H). All seven dolphin sightings were made in NWL, while none was sighted at all in NEL.

5.3.4       During September¡¦s surveys, all seven dolphin sightings were made on primary lines during on-effort search.  One of the dolphin groups was associated with an operating purse-seiner near Lung Kwu Chau.

5.3.5       Distribution of these dolphin sightings made in September 2015 is shown in Figure 6 of Appendix H.  Six of the seven dolphin groups were clustered near Lung Kwu Chau or to the north of the island, while another sighting was made to the west of Sha Chau (Figure 6 of Appendix H).

5.3.6       Notably none of the dolphin sightings were located in the proximity of the HKLR03 and HKBCF reclamation sites, as well as the HKLR09 and TMCLKL alignments (Figure 6 of Appendix H).

5.3.7       During the September¡¦s surveys, encounter rates of Chinese White Dolphins deduced from the survey effort and on-effort sighting data made under favourable conditions (Beaufort 3 or below) are shown in Table 5.3 and Table 5.4.

5.3.8       The average group size of Chinese White Dolphins in September 2015 was only 7.7 individuals per group, which was exceptionally high when compared to previous months of monitoring surveys.  Among the seven groups, five of them were composed of 4-8 dolphins, while there were two large groups with 12 dolphins respectively.

Table 5.3          Individual Survey Event Encounter Rates

 

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)

Primary Lines Only

Primary Lines Only

NEL

Set 1: September 2nd / 11th

0.0

0.0

Set 2: September 17th / 29th

0.0

0.0

NWL

Set 1: September 2nd / 11th

5.5

52.0

Set 2: September 17th / 29th

4.0

21.4

Remarks:

1.     Dolphin Encounter Rates Deduced from the Two Sets of Surveys (Two Surveys in Each Set) in September 2015 in Northeast (NEL) and Northwest Lantau (NWL).

Table 5.4          Monthly Average Encounter Rates

 

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)

Primary   Lines Only

Both Primary and Secondary Lines

Primary   Lines Only

Both Primary and Secondary Lines

Northeast Lantau

0.0

0.0

0.0

0.0

Northwest Lantau

4.7

3.7

36.5

28.7

Remarks:

1.     Monthly Average Dolphin Encounter Rates (Sightings Per 100 km of Survey Effort) from All Four Surveys Conducted in September 2015 on Primary Lines only as well as Both Primary Lines and Secondary Lines in Northeast (NEL) and Northwest Lantau (NWL).

 

Photo-identification Work

5.3.9       Twenty-three individual dolphins were sighted 33 times during September¡¦s surveys (Annex III and IV of Appendix H). The majority of individuals were sighted only once during the monitoring month, but there were also six individuals being sighted twice and two individuals being sighted thrice. 

5.3.10    Notably, three individuals (NL202, NL233 and NL297) were accompanied with calves during their re-sightings.

Conclusion

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

5.3.12    Due to monthly variation in dolphin occurrence within the study area, it would be more appropriate to draw conclusion on whether any impacts on dolphins have been detected related to the construction activities of this project in the quarterly EM&A report, where comparison on distribution, group size and encounter rates of dolphins between the quarterly impact monitoring period (September ¡V November 2015) and baseline monitoring period (3-month period) will be made.

5.4                Reference

5.4.1       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.

5.4.2       Hung, S. K.  2012.  Monitoring of Marine Mammals in Hong Kong waters: final report (2011-12).  An unpublished report submitted to the Agriculture, Fisheries and Conservation Department, 171 pp.

5.4.3       Hung, S. K.  2013.  Monitoring of Marine Mammals in Hong Kong waters: final report (2012-13).  An unpublished report submitted to the Agriculture, Fisheries and Conservation Department, 168 pp.

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


Methodology

6.1.1       To avoid disturbance to the mudflat and nuisance to navigation, no fixed marker/monitoring rod was installed at the monitoring stations. A high precision Global Navigation Satellite System (GNSS) real time location fixing system (or equivalent technology) was used to locate the station in the precision of 1mm, which is reasonable under flat mudflat topography with uneven mudflat surface only at micro level.  This method has been used on Agricultural Fisheries and Conservation Department¡¦s (AFCD) project, namely Baseline Ecological Monitoring Programme for the Mai Po Inner Deep Bay Ramsar Site for measurement of seabed levels.

6.1.2       Measurements were taken directly on the mudflat surface.  The Real Time Kinematic GNSS (RTK GNSS) surveying technology was used to measure mudflat surface levels and 3D coordinates of a survey point.  The RTK GNSS survey was calibrated against a reference station in the field before and after each survey.  The reference station is a survey control point established by the Lands Department of the HKSAR Government or traditional land surveying methods using professional surveying instruments such as total station, level and/or geodetic GNSS.  The coordinates system was in HK1980 GRID system.  For this contract, the reference control station was surveyed and established by traditional land surveying methods using professional surveying instruments such as total station, level and RTK GNSS.  The accuracy was down to mm level so that the reference control station has relatively higher accuracy.  As the reference control station has higher accuracy, it was set as true evaluation relative to the RTK GNSS measurement.  All position and height correction were adjusted and corrected to the reference control station.  Reference station survey result and professional land surveying calibration is shown as Table 6.1:

Table 6.1       Reference Station Survey result and GNSS RTK calibration result of Round 1

Reference Station

Easting (m)

Northing (m)

Baseline reference elevation (mPD) (A)

Round 1 Survey (mPD) (B)

Calibration Adjustment (B-A)

T1

811248.660mE

816393.173mN

3.840

3.817

-0.023

T2

810806.297mE

815691.822mN

4.625

4.653

+0.028

T3

810778.098mE

815689.918mN

4.651

4.660

+0.009

T4

810274.783mE

816689.068mN

2.637

2.709

+0.072

 

6.1.3       The precision of the measured mudflat surface level reading (vertical precision setting) was within 10 mm (standard deviation) after averaging the valid survey records of the XYZ HK1980 GRID coordinates.  Each survey record at each station was computed by averaging at least three measurements that are within the above specified precision setting. Both digital data logging and written records were collected in the field.  Field data on station fixing and mudflat surface measurement were recorded.

Monitoring Locations

6.1.4       Four monitoring stations were established based on the site conditions for the sedimentation monitoring and are shown in Figure 6.1. 

Monitoring Results

6.1.5       The baseline sedimentation rate monitoring was in September 2012 and impact sedimentation rate monitoring was undertaken on 14 June 2015. The mudflat surface levels at the four established monitoring stations and the corresponding XYZ HK1980 GRID coordinates are presented in Table 6.2 and Table 6.3.

Table 6.2       Measured Mudflat Surface Level Results

Baseline Monitoring (September 2012)

Impact Monitoring (September 2015)

Monitoring Station

Easting (m)

Northing (m)

Surface Level

(mPD)

Easting (m)

Northing (m)

Surface Level

(mPD)

S1

810291.160

816678.727

0.950

810291.167

816678.723

1.061

S2

810958.272

815831.531

0.864

810958.278

815831.542

0.960

S3

810716.585

815953.308

1.341

810716.595

815953.340

1.466

S4

811221.433

816151.381

0.931

811221.414

816151.336

1.004

 

Table 6.3       Comparison of measurement 

Comparison of measurement

Remarks and Recommendation

Monitoring Station

Easting (m)

Northing (m)

Surface Level

(mPD)

S1

0.007

-0.004

0.111

Level continuously increased

S2

0.006

0.011

0.096

Level continuously increased

S3

0.010

0.032

0.125

Level continuously increased

S4

-0.019

-0.045

0.073

Level continuously increased

 

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

6.2.1       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. 

6.2.2       Impact water quality monitoring in San Tau (monitoring station SR3) was conducted in June 2015.  The monitoring parameters included dissolved oxygen (DO), turbidity and suspended solids (SS).

6.2.3       The Impact monitoring results for SR3 were extracted and summarised below:


 

Table 6.4       Impact Water Quality Monitoring Results (Depth Average)

Date

Mid Ebb Tide

Mid Flood Tide

DO (mg/L)

Turbidity (NTU)

SS (mg/L)

DO (mg/L)

Turbidity (NTU)

SS (mg/L)

2-Sep-15

5.69

20.40

8.30

5.46

15.85

13.50

4-Sep-15

6.27

7.55

7.35

6.22

4.40

4.60

7-Sep-15

6.32

3.75

3.30

6.43

4.75

5.80

9-Sep-15

6.89

4.65

2.95

7.75

4.80

4.10

11-Sep-15

6.53

5.95

5.35

9.00

7.20

6.80

14-Sep-15

5.82

6.75

6.50

5.74

5.35

7.00

16-Sep-15

5.86

10.70

11.90

5.64

7.50

7.70

18-Sep-15

5.82

8.50

7.50

5.71

6.70

6.20

21-Sep-15

6.07

6.30

5.30

6.58

3.80

2.70

23-Sep-15

6.15

3.80

2.45

7.39

3.30

2.60

25-Sep-15

6.63

5.20

5.90

8.23

10.05

5.20

28-Sep-15

5.27

7.65

7.90

6.04

8.05

8.55

30-Sep-15

5.64

17.15

13.75

5.47

12.45

16.00

Average

6.07

8.33

6.80

6.59

7.25

6.98

 

Sampling Zone

6.3.1       In order to collect baseline information of mudflats in the study site, the study site was divided into three sampling zones (labeled as TC1, TC2, TC3) in Tung Chung Bay and one zone in San Tau (labeled as ST) (Figure 2.1 of Appendix I). The horizontal length of sampling zones TC1, TC2, TC3 and ST were about 250 m, 300 m, 300 m and 250 m, respectively. Survey of horseshoe crabs, seagrass beds and intertidal communities were conducted in every sampling zone. The present survey was conducted in September 2015 (totally 5 sampling days between 5th and 13th September 2015).

Horseshoe Crabs

6.3.2       Active search method was conducted for horseshoe crab monitoring by two experienced surveyors at every sampling zone. During the search period, any accessible and potential area would be investigated for any horseshoe crab individuals within 2-3 hours in low tide period (tidal level below 1.2 m above Chart Datum (C.D.)). Once a horseshoe crab individual was found, the species was identified referencing to Li (2008). The prosomal width, inhabiting substratum and respective GPS coordinate were recorded. A photographic record was taken for future investigation. Any grouping behavior of individuals, if found, was recorded. The horseshoe crab surveys were conducted on 6th (for TC1), 10th (for TC3 and ST) and 12th (for TC2) September 2015. During the survey period, the weather was hot and sunny in TC1, TC3 and ST while it was rainy in TC2.

Seagrass Beds

6.3.3       Active search method was conducted for seagrass bed monitoring by two experienced surveyors at every sampling zone. During the search period, any accessible and potential area would be investigated for any seagrass beds within 2-3 hours in low tide period. Once seagrass bed was found, the species, estimated area, estimated coverage percentage and respective GPS coordinate were recorded. A photographic record was taken for future investigation. The seagrass beds surveys were conducted on 6th (for TC1), 10th (for TC3 and ST) and 12th (for TC2) September 2015. During the survey period, the weather was hot and sunny in TC1, TC3 and ST while it was rainy in TC2.

Intertidal Soft Shore Communities

6.3.4       The intertidal soft shore community surveys were conducted in low tide period on 5th (for ST), 6th (for TC1), 12th (for TC2) and 13th September 2015 (for TC3). At each sampling zone, three 100 m horizontal transects were laid at high tidal level (H: 2.0 m above C.D.), mid tidal level (M: 1.5 m above C.D.) and low tidal level (L: 1.0 m above C.D.). Along every horizontal transect, ten random quadrats (0.5 m x 0.5m) were placed.

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

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

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

Data Analysis

6.3.8       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.

6.4.1       In the event of the impact monitoring results indicating that the density or the distribution pattern of intertidal fauna and seagrass is found to be significant different to the baseline condition (taking into account natural fluctuation in the occurrence and distribution pattern such as due to seasonal change), appropriate actions should be taken and additional mitigation measures should be implemented as necessary.  Data should then be re-assessed and the need for any further monitoring should be established.  The action plan, as given in Table 6.5 should be undertaken within a period of 1 month after a significant difference has been determined. 

Table 6.5          Event and Action Plan for Mudflat Monitoring

Event

ET Leader

IEC

SO

Contractor

Density or the distribution pattern of horseshoe crab, seagrass or intertidal soft shore communities recorded in the impact or post-construction monitoring are  significantly lower than or different from those recorded in the baseline monitoring.

 

Review historical data to ensure differences are as a result of natural variation or previously observed seasonal differences;

Identify source(s) of impact;

Inform the IEC, SO and Contractor;

Check monitoring data;

Discuss additional monitoring and any other measures, with the IEC and Contractor.

Discuss monitoring with the ET and the Contractor;

Review proposals for additional monitoring and any other measures submitted by the Contractor and advise the SO accordingly.

 

Discuss with the IEC additional monitoring requirements and any other measures proposed by the ET;

Make agreement on the measures to be implemented.

 

Inform the SO and in writing;

Discuss with the ET and the IEC and propose measures to the IEC and the ER;

Implement the agreed measures.

 

 

Notes:

ET ¡V Environmental Team

IEC ¡V Independent Environmental Checker

SO ¡V Supervising Officer

 

Horseshoe Crabs

6.5.1       In general, two species of horseshoe crab Carcinoscorpius rotundicauda (total 196 ind.) and Tachypleus tridentatus (total 10 ind.) were recorded in the survey area. Individuals were mainly found on fine sand while few were found on soft mud. The group size varied varied from 2 to 26 individuals for every sight record. Although less number of Tachypleus tridentatus was recorded, the average body size was larger than that of Carcinoscorpius rotundicauda. Photo records were shown in Figure 3.1 of Appendix I while the complete records of horseshoe crab survey in every sampling zone were shown in Annex II of Appendix I.

6.5.2       One big individual of Carcinoscorpius rotundicauda was found trapped in a trash fish net (Figure 3.1 of Appendix I) on ST shore (GPS coordinate: 22¢X 17.385' N, 113¢X 55.460' E). Its prosomal width reached 130.77 mm. After photo recording, it was released to water. This big individual should have had migrated to sub-tidal habitat. It might forage on intertidal habitat occasionally during high tide period. Since intertidal soft shore was no longer a nursery ground for this individual, its record was excluded from the data analysis. It was to avoid mixing up with juvenile population living on soft shore.

6.5.3       Table 3.1 of Appendix I summarizes the survey results of horseshoe crab in present survey. For Carcinoscorpius rotundicauda, it could be found in all sampling zones while more individuals were recorded in TC3 and ST (TC1: 41 ind., TC2: 4 ind., TC3: 70 ind., ST: 81 ind.). The search record was 10.3 ind. hr-1 person-1, 1.0 ind. hr-1 person-1, 11.7 ind. hr-1 person-1, 13.5 ind. hr-1 person-1 in TC1, TC2, TC3 and ST respectively. The size of individuals was similar among TC1 (mean prosomal width: 39.58 mm), TC2 (36.20 mm) and ST (37.03mm) while that of TC3 was smaller (27.27 mm).

6.5.4       For Tachypleus tridentatus, it could be found in TC3 (1 ind.) and ST (9 ind.) only. The search records were 0.2 ind. hr-1 person-1 and 1.5 ind. hr-1 person-1 in TC3 and ST respectively. The mean prosomal width of TC3 (53.90 mm) was larger than that of ST (48.50mm).

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

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

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

Population difference among the sampling zones

6.5.8       Figures 3.3 and 3.4 of Appendix I show the changes of number of individuals, mean prosomal width and search record of horseshoe crabs Carcinoscorpius rotundicauda and Tachypleus tridentatus respectively in every sampling zone along the sampling months. In general, higher search records (i.e. number of individuals) of both species were always found in ST followed by TC3 from September 2012 to September 2014. Then the search record in TC3 was even higher than that in ST from March 2015 to June 2015. In this sampling month (Sep. 2015), highest search record was found in ST again. For TC1, the search record was at low to medium level and fluctuated slightly along the sampling months. In contrast, much lower search record was found in TC2 (2 ind. in September 2013, 1 ind. in March, June, September. 2014, March and June 2015, 4 ind. in September. 2015). For spatial difference of horseshoe crab size, larger individuals were usually found in ST while smaller individuals were usually found in TC3.

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

Seasonal variation of horseshoe crab population

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

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

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

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

Box plot of horseshoe crab populations in TC3

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

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

Box plot of horseshoe crab populations in ST

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

6.5.17    For Tachypleus tridentatus, a consistent growing trend was observed for the major population from December 2012 to December 2014 regardless of change of search record. The prosomal width increased from 15-30 mm to 55-70 mm. As mentioned, the large individuals might have reached a suitable size for migrating from the nursery soft shore to subtidal habitat. From March to June 2015, the size of major population decreased slightly with prosomal width 40-60 mm. It further indicated some of order individuals might have migrated to sub-tidal habitat. From March to September 2015, the size of major population decreased slightly to a prosomal width 40-60 mm. At the same time, the number of individuals decreased gradually. It further indicated some of large individuals might have migrated to sub-tidal habitats.

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

Impact of the HKLR project

6.5.19    The present survey was the 12th survey of the EM&A programme during the construction period. Based on the results, impact of the HKLR project could not be detected on horseshoe crabs considering the factor of natural, seasonal variation. In case, abnormal phenomenon (e.g. very few numbers of horseshoe crab individuals in warm weather, large number of dead individuals on the shore) is observed, it would be reported as soon as possible.

Seagrass Beds

6.5.20    In general, two species of seagrass Halophila ovalis and Zostera japonica were recorded in ST only. Both species were found on sandy substratum nearby the seaward side of mangrove vegetation at 2.0 m above C.D. Two species were found coexisting in two seagrass beds. Photo records were shown in  Figure 3.7 of Appendix I while the complete records of seagrass beds survey were shown in Annex III of Appendix I.

6.5.21    Table 3.2 of Appendix I summarize the results of seagrass beds survey in ST. Four patches of Halophila ovalis were found while the total seagrass bed area was about 91.4 m2 (average area 22.8 m2). The largest patch was a long strand with seagrass bed area 32.0 m2 and variable vegetation coverage 10-80%. Two other patches were smaller strands (17.4 and 26.3 m2) with variable vegetation coverage 30-60%. Both had co-existing seagrass Zostera japonica. The smallest patch was about 15.8 m2 with highest percentage coverage 80%. For Zostera japonica, there were two long strands (17.4-26.3 m2) of seagrass beds with low coverage percentage 10-20%. Both long strands had co-existing seagrass Halophila ovalis. The total seagrass bed area was about 43.7 m2 (average area 21.8 m2).

Temporal variation of seagrass beds

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

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

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

Unfavourable conditions to seagrass Halophila ovalis

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

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

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

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

6.5.29    From March to June 2015, 2-3 small patches of Halophila ovalis were newly found coinhabiting with another seagrass species Zostera japonica. But its total patch area was still very low relative to the previous records. The recolonization rate was low while cold weather and insufficient sunlight were possible factors between December 2014 and March 2015. Moreover, it would need to compete with more abundant seagrass Zostera japonica for substratum and nutrient. Since Zostera japonica had extended and had covered the original seagrass bed of Halophila ovalis at certain degree. In September 2015, the total seagrass area of Halophila ovalis had increased rapidly from 6.8 m2 to 91.35 m2. It had recolonized its original patch locations and covered Zostera japonica. Hence it was expected that the seagrass bed of Halophila ovalis would increase continually in the following months.

Impact of the HKLR project

6.5.30    The present survey was the 12th survey of the EM&A programme during the construction period. According to the results of present survey, there was recolonization of both seagrass species Halophila ovalis and Zostera japonica in ST. The seagrass patches were believed in recovery. Hence the negative impact of HKLR project on the seagrass was not significant. In case, adverse phenomenon (e.g. reduction of seagrass patch size, abnormal change of leave colour) is observed again, it would be reported as soon as possible.

Intertidal Soft Shore Communities

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

¡P                In TC1, high percentage of ¡¥Sands¡¦ (70%) was recorded at high tidal level which was different from previous records (high percentage of ¡¥Gravels and Boulders¡¦). By direct observation on site, there was no obvious change of substratum at high tidal level. Hence it was simply due to more random quadrats laid on sandy substratum in this sampling. High percentage of ¡¥Gravels and Boulders¡¦ was recorded (80-100%) at mid and low tidal levels.

¡P                In TC2, the substratum distribution was different between tidal levels. At high tidal level, higher percentage of ¡¥Sands¡¦ (60%) was recorded followed by ¡¥Soft mud¡¦ (30%). At mid tidal level, higher percentage of ¡¥Sands¡¦ (70%) was recorded followed by ¡¥Gravels and Boulders¡¦ (30%). At low tidal level, higher percentage of ¡¥Soft mud¡¦ (60%) was recorded followed by ¡¥Sands¡¦ (40%).

¡P                In TC3, the substratum type was clearly different between high-mid tidal level and low tidal level. ¡¥Sands¡¦ was the main substratum type (90-100%) at high and mid tidal levels while ¡¥Gravels and Boulders¡¦ was the main substratum type (100%) at low tidal level.

¡P                In ST, the substratum type was clearly different between high-mid tidal level and low tidal level. ¡¥Gravels and Boulders¡¦ (90-100%) was the main substratum at high and mid tidal levels. At low tidal level, higher percentage of ¡¥Sands¡¦ (70%) was recorded followed by ¡¥Gravels and Boulders¡¦ (30%).

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

6.5.33    Table 3.4 of Appendix I lists the total abundance, density and number of taxon of every phylum in this survey. A total of 12502 individuals were recorded. Mollusca was significantly the most abundant phylum (total individuals 11994, density 400 ind. m-2, relative abundance 95.9%). The second abundant phylum was Arthropoda (383 ind., 13 ind. m-2, 3.1%). The third and fourth abundant phyla were Annelida (71 ind., 2 ind. m-2, 0.6%) and Sipuncula (23 ind., 1 ind. m-2, 0.2%). Relatively other phyla were very low in abundances (density £1 ind. m-2, relative abundance £0.1%). Moreover, the most diverse phylum was Mollusca (35 taxa) followed by Arthropoda (13 taxa) and Annelida (9 taxa). There was 1 taxon recorded only for other phyla. The complete list of collected specimens is shown in Annex V of Appendix I.

6.5.34    Table 3.5 of Appendix I show the number of individual, relative abundance and density of each phylum in every sampling zone. The total abundance (2454-4506 ind.) varied among the four sampling zones while the phyla distributions were similar. In general, Mollusca was the most dominant phylum (no. of individuals: 2359-4297 ind.; relative abundance 94.9-98.0%; density 315-573 ind. m-2). Other phyla were significantly lower in number of individuals. Arthropoda was the second abundant phylum (35-169 ind.; 1.4-3.8%; 5-23 ind. m-2). Annelida was the third abundant phylum (32-35 ind.; 0.8-1.1%; 4-5 ind. m-2) in TC2 and TC3. Sipuncula was the third or fourth abundant phylum (8-9 ind.; 0.3%; 1 ind. m-2) in TC1 and TC2. Cnidaria (sea anemone) was the third abundant phylum (12 ind.; 0.5%; 2 ind. m-2) in ST. Relatively other phyla were low in abundance among the four sampling zones (≤ 0.3%).

Dominant species in every sampling zone

6.5.35    Table 3.6 of Appendix I lists the abundant species (relative abundance >10%) in every sampling zone. In TC1, gastropod Batillaria multiformis was the most abundant species (54 ind. m-2, relative abundance 29%) followed by gastropods Cerithidea djadjariensis (47 ind. m-2, 25%) and Cerithidea cingulata (38 ind. m-2, 20%) at high tidal level (major substratum: ¡¥Sands¡¦). However all abundant species were at low density relative to other sampling zones. At mid tidal level (major substratum: ¡¥Gravels and Boulders¡¦), the abundant species were gastropods Monodonta labio (112 ind. m-2, 34%), Batillaria multiformis (79 ind. m-2, 24%) and rock oyster Saccostrea cucullata (72 ind. m-2, 22%, attached on boulders) at low-moderate densities. At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), gastropod Monodonta labio (242 ind. m-2, 47%) and rock oyster Saccostrea cucullata (121 ind. m-2, 24%) were abundant at moderate-high densities.

6.5.36    At TC2, gastropod Cerithidea djadjariensis (407 ind. m-2, 53%) was the most abundant at high density followed by Cerithidea cingulata (157 ind. m-2, 20%) at high tidal level (major substratum: ¡¥Sands¡¦). Relative to high tidal level, the density of every taxon was much lower and similar at mid and low tidal levels. No dominant species was determined. At mid tidal level (major substratum: ¡¥Sands¡¦), rock oyster Saccostrea cucullata (76 ind. m-2, 25%, attached on boulders), gastropods Batillaria zonalis (73 ind. m-2, 24%), Monodonta labio (44 ind. m-2, 15%) and   Cerithidea djadjariensis (31 ind. m-2, 10%) were commonly occurring at low density. At low tidal level (major substratum: ¡¥Soft mud¡¦), Batillaria zonalis (41 ind. m-2, 34%), rock oyster Saccostrea cucullata (24 ind. m-2, 20%) and barnacle Balanus amphitrite (19 ind. m-2, 16%, attached on boulders) were commonly occurring at low density.

6.5.37    At TC3, the abundant species were similar with variable densities at high and mid tidal levels (major substratum: ¡¥Sands¡¦). There were gastropods Cerithidea djadjariensis (146-257 ind. m-2, 25-35%), Batillaria multiformis (143-256 ind. m-2, 25-35%) and Cerithidea cingulata (128-222 ind. m-2, 18-39%) at moderate densities. At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), gastropod Monodonta labio (197 ind. m-2, 39%) and rock oyster Saccostrea cucullata (146 ind. m-2, 29%, attached on boulders) were abundant at moderate densities. Little black mussel Xenostrobus atratus (48 ind. m-2, 10%) was the third abundant species at low density.

6.5.38    At ST, gastropod Monodonta labio (130-145 ind. m-2, 34-38%) and rock oyster Saccostrea cucullata (80-91 ind. m-2, 21-24%, attached on boulders) were the abundant species of low-moderate densities at high and mid tidal levels (major substratum: ¡¥Gravels and Boulders¡¦). Gastropods Batillaria multiformis (76 ind. m-2, 20%) and Lunella coronata (45 ind. m-2, 12%) were the third abundant species at high tidal level and mid tidal level respectively. At low tidal level (major substratum: ¡¥Sands¡¦), rock oyster Saccostrea cucullata (71 ind. m-2, 33%) was the most abundant followed by gastropods Lunella coronata (41 ind. m-2, 19%) and Euchelus scaber (30 ind. m-2, 14%). All three species were at low densities.

6.5.39    In general, there was no consistent zonation pattern of species distribution observed across all sampling zones and tidal levelsThe species distribution should be determined by the type of substratum primarily. In general, gastropods Cerithidea djadjariensis (total number of individuals: 2350 ind., relative abundance 18.8%), Batillaria multiformis (1757 ind., 14.1%), and Cerithidea cingulata (1561 ind., 12.5%) and Batillaria zonalis (468 ind., 3.7%) were the most commonly occurring species on sandy and soft mud substrata. Gastropods Monodonta labio (2249 ind., 18.0%), Lunella coronata (408 ind., 3.3%) and rock oyster Saccostrea cucullata (1930 ind., 15.4%) were commonly occurring species inhabiting gravel and boulders substratum.

6.5.40    Relative to the results of previous sampling (June 2015), the densities of gastropod Batillaria multiformis declined sharply in TC1, TC3 and ST. Heat stress was one possible cause of population decline. According to the online database of Hong Kong Observatory, there were 14, 13 and 18 days with ¡¥Very Hot Weather Warning¡¦ in June, July and August 2015 respectively (total 45 days) with mean monthly ambient temperature 29.1-29.7 ˚C. Moreover majority of low tide period occurs in day time of summer (especially afternoon) in Hong Kong. The substratum between mid and high tidal levels would be strongly heated under direct sunshine with little water splashing. Since this gastropod species usually inhabits at high and mid tidal levels, high mortality rate would be resulted. Its population was believed to be restored gradually during dry season.

Biodiversity and abundance of soft shore communities

6.5.41    Table 3.7 of Appendix I shows the mean values of number of species, density, biodiversity index H¡¦ and species evenness J of soft shore communities at every tidal level and in every sampling zone. Among the sampling zones, the mean species number (10 spp. 0.25 m-2) and mean H¡¦ (1.6) in ST were slightly higher than other sampling zones (mean species number: 8 spp. 0.25 m-2, H¡¦ 1.3-1.4). The mean densities were quite variable among sites. The mean density of TC3 (601 ind. m-2) was higher than other sampling zones (327-398 ind. m-2). However mean J showed no clear difference among sampling zones (0.6-0.7).

6.5.42    Across the tidal levels, there was no consistent difference of the mean number of species, H¡¦ and J in all sampling zones. For the mean density, a general decreasing trend was observed from high tidal level to low tidal level at TC2, TC3 and ST. At TC1, the mean density at low tidal level was higher than that at high and mid tidal levels. As mentioned, the variation of mean density should be determined by the type of substratum primarily.

6.5.43    Figures 3.11 to 3.14 of Appendix I show the temporal changes of mean number of species, mean density, H¡¦ and J at every tidal level and in every sampling zone along the sampling months. From Jun. to Sep. 2015, the mean densities decreased clearly at high tidal level in TC1 and ST. As mentioned, it was due to higher mortality of dominant gastropod Batillaria multiformis under heat stress of wet season. Overall no consistent temporal change of any biological parameters was observed. All the parameters were under slight and natural fluctuation with the seasonal variation.

Impact of the HKLR project

6.5.44    The present survey was the 12th survey of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project were not detected on intertidal soft shore community. In case, abnormal phenomenon (e.g. large reduction of fauna densities and species number) is observed, it would be reported as soon as possible. 

6.6.1       Chan, K.K., Caley, K.J., 2003. Sandy Shores, Hong Kong Field Guides 4. The Department of Ecology & Biodiversity, The University of Hong Kong. pp 117.

6.6.2       Dai, A.Y., Yang, S.L., 1991. Crabs of the China Seas. China Ocean Press. Beijing.

6.6.3       Dong, Y.M., 1991. Fauna of ZheJiang Crustacea. Zhejiang Science and Technology Publishing House. ZheJiang.

6.6.4       EPD, 1997. Technical Memorandum on Environmental Impact Assessment Process (1st edition). Environmental Protection Department, HKSAR Government.

6.6.5       Fauchald, K., 1977. The polychaete worms. Definitions and keys to the orders, families and genera. Natural History Museum of Los Angeles County, Science Series 28. Los Angeles, U.S.A.

6.6.6       Fong, C.W., 1998. Distribution of Hong Kong seagrasses. In: Porcupine! No. 18. The School of Biological Sciences, The University of Hong Kong, in collaboration with Kadoorie Farm & Botanic Garden Fauna Conservation Department, p10-12.

6.6.7       Li, H.Y., 2008. The Conservation of Horseshoe Crabs in Hong Kong. MPhil Thesis, City University of Hong Kong, pp 277.

6.6.8       Longstaff, B.J., Dennison, W.C., 1999. Seagrass survival during pulsed turbidity events: the effects of light deprivation on the seagrasses Halodule pinifolia and Halophila ovalis. Aquatic Botany 65 (1-4), 105-121.

6.6.9       Longstaff, B.J., Loneragan, N.R., O¡¦Donohue, M.J., Dennison, W.C., 1999. Effects of light deprivation on the survival and recovery of the seagrass Halophila ovalis (R. Br.) Hook. Journal of Experimental Marine Biology and Ecology 234 (1), 1-27.

6.6.10    Nakaoka, M., Aioi, K., 1999. Growth of seagrass Halophila ovalis at dugong trails compared to existing within-patch variation in a Thailand intertidal flat. Marine Ecology Progress Series 184, 97-103.

6.6.11    Pielou, E.C., 1966. Shannon¡¦s formula as a measure of species diversity: its use and misuse. American Naturalist 100, 463-465.

6.6.12    Qi, Z.Y., 2004. Seashells of China. China Ocean Press. Beijing, China.

6.6.13    Qin, H., Chiu, H., Morton, B., 1998. Nursery beaches for Horseshoe Crabs in Hong Kong. In: Porcupine! No. 18. The School of Biological Sciences, The University of Hong Kong, in collaboration with Kadoorie Farm & Botanic Garden Fauna Conservation Department, p 9-10.

6.6.14    Shannon, C.E., Weaver, W., 1963. The Mathematical Theory of Communication. Urbana: University of Illinois Press, USA.

6.6.15    Shin, P.K.S., Li, H.Y., Cheung, S.G., 2009. Horseshoe Crabs in Hong Kong: Current Population Status and Human Exploitation. Biology and Conservation of Horseshoe Crabs (part 2), 347-360.

6.6.16    Supanwanid, C., 1996. Recovery of the seagrass Halophila ovalis after grazing by dugong. In: Kuo, J., Philips, R.C., Walker, D.I., Kirkman, H. (eds), Seagrass biology: Proc Int workshop, Rottenest Island, Western Australia. Faculty of Science, The University of Western Australia, Nedlands, 315-318.

6.6.17    Vermaat, J.E., Agawin, N.S.R., Duarte, C.M., Fortes, M.D., Marba. N., Uri, J.S., 1995. Meadow maintenance, growth and productivity of a mixed Philippine seagrass bed. Marine Ecology Progress Series 124, 215-225.

6.6.18    Yang, D.J, Sun, R.P., 1988. Polychaetous annelids commonly seen from the Chinese waters (Chinese version). China Agriculture Press, China.



7        Environmental Site Inspection and Audit

7.1.1       Site Inspections were carried out on a weekly basis to monitor the implementation of proper environmental pollution control and mitigation measures for the Project. During the reporting month, five site inspections were carried out on 2, 9, 16, 25 and 30 September 2015. 

7.1.2       Particular observations during the site inspections and the follow up actions taken by the Contractor are described below.

2 September 2015

(a)     The alignment of silt curtains did not follow the design plan at Portion X. The silt curtains was realigned to follow the design plan. This observation was found on 22 July 2015 and closed on 2 September 2015.  

(b)     A gap was observed between sections of silt curtains at Portion X. The gap was filled up by additional silt curtains. This observation was found on 22 July 2015 and closed on 2 September 2015.  

(c)     Dry dusty material was found on the ground after the loading/unloading activity at S7. The dry dusty material was cleaned up by the Contractor. This observation was found on 5 August 2015 and closed on 2 September 2015.  

(d)     A stockpile of dry crushed stones was found at S7. Water spraying was provided for the stockpile of dry crushed stone. This observation was found on 5 August 2015 and closed on 2 September 2015.  

(e)     No drip tray was provided for chemical containers at S15. A drip tray was provided for the chemical containers. This observation was found on 12 August 2015 and closed on 2 September 2015.  

(f)      The silt curtain which should be placed around the aeronautical light was broken at Portion X. The broken silt curtain around the aeronautical light at Portion X was replaced. This observation was found on 19 August 2015 and closed on 2 September 2015.  

(g)     The rubbish bin at access road of WA6 was full. The rubbish was removed. This observation was found on 28 August 2015 and closed on 2 September 2015.  

(h)     A drip tray was not provided to the chemical containers inside West Tunnel. The chemical containers were removed. This observation was found on 28 August 2015 and closed on 2 September 2015.  

(i)      A drip tray was not provided for the chemical containers under the bridge at West Tunnel site. The chemical containers were removed. This observation was found on 28 August 2015 and closed on 2 September 2015.  

(j)      The container for collecting general wastes was full and rubbish was placed next to the container at S15. The rubbish was removed by the Contractor. This observation was found on 2 September 2015 and closed on 9 September 2015.

(k)     The alignment of the silt curtain did not follow the design plan at Portion X. This observation has been outstanding since 2 September 2015. The Contractor was reminded to follow the design plan of silt curtain at Portion X.

(l)      Muddy water was leaked from the wheel washing bay to the sea at S7. The muddy water discharge was stopped by diverting the wastewater to a sump pit. This observation was found on 2 September 2015 and closed on 9 September 2015.

(m)   Stagnant water was accumulated inside an I-beam at N4. The stagnant water was cleaned up by the Contractor. This observation was found on 2 September 2015 and closed on 9 September 2015.

(n)     Stagnant water was observed inside a drip tray at N4. The stagnant water inside the drip tray was cleaned up. This observation was found on 2 September 2015 and closed on 9 September 2015.

(o)     Many emptied cement bags were placed on the ground at S11. The emptied cement bags were removed. This observation was found on 2 September 2015 and closed on 9 September 2015.

(p)     Stagnant water was found inside an abandon wheel washing bay at N20. The stagnant water was cleaned up inside the abandon wheel washing bay. This observation was found on 2 September 2015 and closed on 16 September 2015.

9 September 2015

(a)     The alignment of the silt curtain did not follow the design plan at Portion X. This observation has been outstanding since 2 September 2015. The Contractor was reminded to follow the design plan of silt curtain at Portion X.

(b)     Rubbish was accumulated on the ground at N1. The rubbish was removed by contractor. This observation was found on 9 September 2015 and closed on 16 September 2015.

(c)     There were not enough sand bags to be placed along the boundary of dusty materials at N1. Additional sand bags were placed along the boundary of the dusty materials. This observation was found on 9 September 2015 and closed on 16 September 2015.

(d)     Sand bags placed along the road were broken at N20. The broken sand bags were removed and new sand bags were placed along the road. This observation was found on 9 September 2015 and closed on 16 September 2015.

(e)     A container for general refuse was full and rubbish was placed next to the container at S15. The rubbish was removed by the Contractor. This observation was found on 9 September 2015 and closed on 16 September 2015.

(f)      A wastewater treatment plant was not used at S25. The wastewater was contained within the construction site.  After the site inspection, the Contractor pump the wastewater to wastewater treatment plant for treatment prior to discharge. This observation was found on 9 September 2015 and closed on 16 September 2015.

(g)     Surface runoff was not directed to a wastewater treatment system at N1. The surface runoff was pumped to a wastewater treatment system for treatment after the site inspection.  This observation was found on 9 September 2015 and closed on 16 September 2015.

(h)     Stagnant water was observed inside an abandon wheel washing bay at N20. The stagnant water inside the abandon wheel washing bay was cleaned up. This observation was found on 9 September 2015 and closed on 16 September 2015.

16 September 2015

(a)     The alignment of the silt curtain did not follow the design plan at Portion X. This observation has been outstanding since 2 September 2015. The Contractor was reminded to follow the design plan of silt curtain at Portion X.

(b)     No sand bags were placed around the storage area for aggregate / clay at vessel Shun Tat 82. Sand bags were placed the around the storage area for aggregate / clay. This observation was found on 16 September 2015 and closed on 25 September 2015.

(c)     Rubbish was found near seaside at S7. The rubbish was removed. This observation was found on 16 September 2015 and closed on 25 September 2015.

(d)     Muddy surface runoff was observed at S7. The muddy water runoff was stopped by the Contractor. This observation was found on 16 September 2015 and closed on 25 September 2015.

(e)     A drilling machine was partly covered and fugitive dust was observed at S15. A proper cover was provided to the drilling machines at S15. This observation was found on 16 September 2015 and closed on 25 September 2015.

(f)      No labour was provided for a wheel washing facility at WA4 to wash wheels of vehicles leaving the site. A labour was provided to wash wheels of vehicles at WA4. This observation was found on 16 September 2015 and closed on 25 September 2015.

(g)     A rubbish bin at WA6 was full. The rubbish was removed. This observation was found on 16 September 2015 and closed on 25 September 2015.

(h)     Holes of water barriers were not sealed at WA6. Holes of the water barriers at WA6 were sealed. This observation was found on 16 September 2015 and closed on 25 September 2015.

25 September 2015

(a)     The alignment of the silt curtain did not follow the design plan at Portion X. This observation has been outstanding since 2 September 2015. The Contractor was reminded to follow the design plan of silt curtain at Portion X.

(b)     Mechanical cover of dump truck was not covered near at Portion Y. The mechanical cover of a dump truck was closed during transportation of materials at Portion Y. This observation was found on 25 September 2015 and closed on 30 September 2015.

(c)     Water dripping from air-conditioner was observed at Portion Y. The Contractor used a red bucket to contain the water dripping. This observation was found on 25 September 2015 and closed on 30 September 2015.

(d)     Accumulated rubbish was observed at Portion Y. The rubbish was removed. This observation was found on 25 September 2015 and closed on 30 September 2015.

(e)     No drip tray was observed for the oil drums at Portion Y. Drip trays were provided for the oil drums. This observation was found on 25 September 2015 and closed on 30 September 2015.

(f)      Stagnant water was observed at Portion Y. The stagnant water was cleared up. This observation was found on 25 September 2015 and closed on 30 September 2015.

(g)     Stagnant water was observed at S16 site entrance. The stagnant water was cleared up. This observation was found on 25 September 2015 and closed on 30 September 2015.  

(h)     Rubbish was observed inside the tunnel at N1. The rubbish was removed. This observation was found on 25 September 2015 and closed on 30 September 2015.

30 September 2015

(a)     The alignment of the silt curtain did not follow the design plan at Portion X. This observation has been outstanding since 2 September 2015. The Contractor was reminded to follow the design plan of silt curtain at Portion X.

(b)     Muddy water was leaked out from holes of sand bucket into the sea from the storage area at Shun Tat 82. The Contractor was reminded to block the holes of the sand bucket and stop leaking of muddy water.  

(c)     The alignment of silt curtain for barging point did not follow the design plan at Portion X. The Contractor was reminded to follow the design plan of silt curtain at Portion X.

(d)     No sand bags were placed along the road at N20. The Contractor was reminded to place sand bags along the road at N20.

(e)     Wheels of a dump truck were not washed before leaving the site at N20. The Contractor was reminded to provide wheel washing for the dump truck before leaving the site at N20

(f)      Stagnant water pool was observed on surface at S8. The Contractor was reminded to clean up the stagnant water at S8.

(g)     No water spraying was provided for drilling activity at S8. The Contractor was reminded to provide the water spraying for drilling activity at S8. 

(h)     Unpaved road was dry and fugitive dust emission was observed when there was vehicle movement at S16. The Contractor was reminded to spray water regularly on the unpaved road at S16.

(i)      No sand bags were placed along the site boundary at S25 and there was a potential to wash away the sand into the sea. The Contractor was reminded to provide sand bags along the site boundary at S25.

(j)      A wastewater treatment was not used at S25. The Contractor was reminded to use the wastewater treatment system at S25 if necessary.

(k)     General waste was accumulated on bare ground at S25. The Contractor was reminded to collect the general waste and disposal of regularly at S25.

The Contractor has rectified most of the observations as identified during environmental site inspections within the reporting month. Follow-up actions for outstanding observations will be inspected during the next site inspections. 

7.2               Advice on the Solid and Liquid Waste Management Status

7.2.1       The Contractor registered as a chemical waste producer for the Project. Sufficient numbers of receptacles were available for general refuse collection and sorting.

7.2.2       Monthly summary of waste flow table is detailed in Appendix J.

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

7.3.1       The valid environmental licenses and permits during the reporting month are summarized in Appendix L.

7.4.1       In response to the site audit findings, the Contractors have rectified most of the observations as identified during environmental site inspections during the reporting month. Follow-up actions for outstanding observations will be inspected during the next site inspections.

7.4.2       A summary of the Implementation Schedule of Environmental Mitigation Measures (EMIS) is presented in Appendix M. Most of the necessary mitigation measures were implemented properly.

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

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

7.5.1       No Action and Limit Level exceedances of 1-hour TSP and 24-hr TSP level were recorded at AMS5 and AMS6 during the reporting month.

7.5.2       For construction noise, no Action and Limit Level exceedances were recorded at the monitoring stations during the reporting month.

7.5.3       For marine water quality monitoring, one Action Level exceedances of suspended solid level were recorded during the reporting month. No Limit Level exceedance of suspended solid level was recorded. No Action Level/ Limit Level exceedances of turbidity level and dissolved oxygen level were recorded during the reporting month.

7.6               Summary of Complaints, Notification of Summons and Successful Prosecution

7.6.1       There were no complaints received during the reporting month. However, EPD informed SOR and IEC that there was an enquiry regarding untreated wastewater discharge on 29 September 2015 via email.  An investigation is being undertaken and investigation report will be sent to EPD for record. The details of cumulative statistics of Environmental Complaints are provided in Appendix K.

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

7.6.3       Statistics on notifications of summons and successful prosecutions are summarized in Appendix N.  


8        Future Key Issues

8.1.1       As informed by the Contractor, the major construction activities for October 2015 are summarized in Table 8.1.

Table 8.1          Construction Activities for October 2015

Site Area

Description of Activities

Portion X

Dismantling/Trimming of Temporary 40mm Stone Platform for Construction of Seawall

Portion X

Filling Works behind Stone Platform

Portion X

Construction of Seawall

Portion X

Loading and Unloading of Filling Material

Portion X

Pipe Piling

Portion X

Band Drains Installation

Portion X

Excavation and Lateral Support Works at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Laying Blinding Layer for Tunnel Box Structure at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Construction of Tunnel Box Structure at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Socket H-Piling work at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Construction of Sheet Pile at Scenic Hill Tunnel (Cut & Cover Tunnel)

Portion X

Excavation Works for HKBCF to Airport Tunnel

Portion X

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

Portion X

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

Portion X

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

Airport Road

Works for Diversion of Airport Road

Airport Road / Airport Express Line/East Coast Road

Utilities Detection

Airport Road / Airport Express Line/East Coast Road

Establishment of Site Access

Airport Road/Airport Express Line

Canopy Pipe Drilling/ Mined Tunnel Excavation/ Box Jacking underneath Airport Road and Airport Express Line

Kwo Lo Wan Road

Excavation and Lateral Support Works at shaft 3 extension north shaft & south shaft

Airport Road

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

Portion Y

Utility Culvert Excavation

Portion Y

Highway Operation and Maintenance Area Building Foundation & Sub-structure Works

West Portal

Excavation for Scenic Hill Tunnel

West Portal

Ventilation Building Foundation and Superstructure Works

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

8.2               Environmental Monitoring Schedule for the Coming Month

8.2.1       The tentative schedule for environmental monitoring in October 2015 is provided in Appendix D.

9.1.1       The construction phase and EM&A programme of the Contract commenced on 17 October 2012.

Air Quality

9.1.2       No Action and Limit Level exceedances of 1-hour TSP and 24-hr TSP level were recorded at AMS5 and AMS6 during the reporting month.

Noise

9.1.3       For construction noise, no Action and Limit Level exceedances were recorded at the monitoring stations during the reporting month.

Water Quality

9.1.4       For marine water quality monitoring, one Action Level exceedances of suspended solid level were recorded during the reporting month. No Limit Level exceedance of suspended solid level was recorded. No Action Level/ Limit Level exceedances of turbidity level and dissolved oxygen level were recorded during the reporting month.

Dolphin

9.1.5       During the September¡¦s surveys of the Chinese White Dolphin, no adverse impact from the activities of this construction project on Chinese White Dolphins was noticeable from general observations.

9.1.6       Due to monthly variation in dolphin occurrence within the study area, it would be more appropriate to draw conclusion on whether any impacts on dolphins have been detected related to the construction activities of this project in the quarterly EM&A report, where comparison on distribution, group size and encounter rates of dolphins between the quarterly impact monitoring period (September 2015 ¡V November 2015) and baseline monitoring period (3-month period) will be made.

Mudflat

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

9.1.8       The September 2015 survey results indicate that the impacts of the HKLR project could not be detected on horseshoe crabs, seagrass and intertidal soft shore community.

Environmental Site Inspection and Audit

9.1.9       Environmental site inspection was carried out on 2, 9, 16, 25 and 30 September 2015.  Recommendations on remedial actions were given to the Contractors for the deficiencies identified during the site inspections.

9.1.10    There were no complaints received in relation to the environmental impact during the reporting period.

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