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.75 (December 2018)
17 January 2019
Revision
2
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.. 8
3.1 Monitoring
Requirements. 8
3.2 Monitoring
Equipment 8
3.3 Monitoring
Locations. 8
3.4 Monitoring
Parameters, Frequency and Duration.. 8
3.5 Monitoring
Methodology.. 9
3.6 Monitoring
Schedule for the Reporting Month.. 9
3.7 Monitoring
Results. 10
4....... Water
Quality Monitoring.. 11
4.1 Monitoring
Requirements. 11
4.2 Monitoring
Equipment 12
4.3 Monitoring
Parameters, Frequency and Duration.. 12
4.4 Monitoring
Locations. 12
4.5 Monitoring
Methodology.. 13
4.6 Monitoring
Schedule for the Reporting Month.. 14
4.7 Monitoring
Results. 14
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.. 36
7....... Environmental Site
Inspection and Audit 38
7.1 Site
Inspection.. 38
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.. 39
8....... Future
Key Issues. 41
8.1 Construction
Programme for the Coming Months. 41
8.2 Environmental
Monitoring Schedule for the Coming Month.. 41
9....... Conclusions. 42
9.1 Conclusions. 42
Figures
Figure 1.1 Location
of the Site
Figure 2.1 Environmental Monitoring Stations
Figure 6.1 Mudflat Survey Areas
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/K for HKBCF were issued on 22 December
2014 and 11 April 2016, respectively. These documents are available through the
EIA Ordinance Register. The construction phase of Contract was commenced on 17 October 2012.
BMT Hong Kong 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 seventy-fifth 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 31 December 2018.
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
|
5, 11, 17, 21, 27 and 31 December 2018
|
24-hr TSP Monitoring
Noise Monitoring
|
4, 10, 14, 20, 24 and 28 December 2018
5, 11, 19, 27 and 31 December 2018
|
Water
Quality Monitoring
|
3, 5, 7, 10, 12,
14, 17, 19, 21, 24, 26, 28 and 31 December 2018
|
Chinese White Dolphin Monitoring
Mudflat Monitoring(Ecology)
Mudflat Monitoring (Sedimentation rate)
|
3, 5, 10 and 12 December 2018
1, 2, 11, 15 and 16 December 2018
1 December 2018
|
Site Inspection
|
5, 12, 19 and 28 December 2018
|
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)
|
2
|
0
|
Turbidity level
|
0
|
0
|
Dissolved oxygen level (DO)
|
0
|
0
|
Complaint Log
There was one complaint
received in relation to the environmental impacts during this reporting month.
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: 813273E, 818850N) 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.
The water quality
monitoring stations at IS10 (Coordinate: 812577E, 820670N) and SR5 (811489E,
820455N) are located inside Hong Kong International Airport (HKIA) Approach
Restricted Areas. The previously granted Vessel's Entry Permit for accessing
stations IS10 and SR5 were expired on 31 December 2016. During the permit
renewing process, the water quality monitoring location was shifted to IS10(N)
(Coordinate: 813060E, 820540N) and SR5(N) (Coordinate: 811430E, 820978N) on 2,
4 and 6 January 2017 temporarily. The permit has been granted by Marine
Department on 6 January 2017. Thus, the impact water quality monitoring works
at original monitoring location of IS10 and SR5 has been resumed since 9
January 2017.
Transect lines 2, 3, 4, 5,
6 and 7 for dolphin monitoring have been revised and transect line 24 has been
added due to the presence of a work zone to the north of the airport platform
with intense construction activities in association with the construction of
the third runway expansion for the Hong Kong International Airport. The EPD
issued a memo and confirmed that they had no objection on the revised transect
lines on 28 July 2017. The alternative dolphin transect lines are adopted starting
from August¡¦s dolphin monitoring.
A new water quality monitoring team has been employed for carrying out
water quality monitoring work for the Contract starting from 23 August 2017. Due to marine work of the Expansion of Hong Kong
International Airport into a Three-Runway System (3RS Project), original
locations of water quality monitoring stations CS2, SR5 and IS10 are enclosed
by works boundary of 3RS Project. Alternative impact water quality monitoring
stations, naming as CS2(A), SR5(N) and IS10(N) was approved on 28 July 2017 and
were adopted starting from 23 August 2017 to replace the original locations of
water quality monitoring for the Contract.
The role and responsibilities as the ET Leader of the Contract was temporarily
taken up by Mr Willie Wong instead of Ms Claudine Lee from 25 September 2017 to
31 December 2017.
Water quality monitoring
station SR10A(N) (Coordinate: 823644E, 823484N) was unreachable on 4 October
2017 during flood tide as fishing activities were observed. As such, the water
monitoring at station SR10A(N) was conducted at Coordinate: 823484E, 823593N
during flood tide on 4 October 2017 temporarily.
The topographical condition of the water monitoring
stations SR3 (Coordinate: 810525E, 816456N), SR4 (Coordinate: 814760E, 817867N),
SR10A (Coordinate: 823741E, 823495N) and SR10B (Coordinate: 823686E, 823213N) cannot
be accessed safely for undertaking water quality monitoring. The water quality
monitoring has been temporarily conducted at alternative stations, namely
SR3(N) (Coordinate 810689E, 816591N), SR4(N) (Coordinate: 814705E, 817859N) and
SR10A(N) (Coordinate: 823644E, 823484N) since 1 September 2017. The water
quality monitoring at station SR10B was temporarily conducted at Coordinate:
823683E, 823187N on 1, 4, 6, 8 September 2017 and has been temporarily
fine-tuned to alternative station SR10B(N2) (Coordinate: 823689E, 823159N)
since 11 September 2017. Proposal for permanently relocating the aforementioned
stations was approved by EPD on 8 January 2018.
According to latest
information received in July 2018, the works area WA7 was handed over to other
party on 28 February 2018 instead of 31 January 2018.
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:
¡P
Dismantling/ trimming of Temporary 40mm Stone Platform for Construction
of Seawall at Portion X;
¡P
Construction of Seawall at
Portion X;
¡P
Loading and Unloading
Filling Materials at Portion X;
¡P
Backfilling at Scenic Hill
Tunnel (Cut & Cover Tunnel) at Portion X;
¡P
Works for Diversion of
Airport Road;
¡P
Establishment of Site
Access at Airport Road / Airport Express Line/ East Coast Road;
¡P
Finishing Works for Highway
Operation and Maintenance Area Building at Portion X; and
¡P
Finishing Works for
Scenic Hill Tunnel West Portal Ventilation building at West Portal.
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/K for HKBCF
were issued on 22 December 2014 and 11 April 2016, respectively. These
documents are available through the EIA Ordinance Register. The construction phase of Contract was commenced on 17 October 2012. The works area WA7 was
handed over to other party on 28 February 2018. 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 seventy-fifth 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 31 December 2018.
1.1.6 BMT Hong Kong 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
Hong
Kong Limited 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 Hong Kong Limited)
|
Environmental Project Office Leader
|
Y. H. Hui
|
3465 2888
|
3465 2899
|
Independent Environmental Checker
|
Antony Wong (See Remark 1)
|
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 Hong Kong Limited)
|
Environmental Team Leader
|
Claudine Lee
|
2241 9847
|
2815 3377
|
24 hours complaint
hotline
|
---
|
---
|
5699 5730
|
---
|
Remark:
(1) Mr. Ray Yan has taken
up the role of Independent Environmental Checker staring from 1 January 2019.
|
|
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
|
Construction
of seawall
|
Portion X
|
Loading
and unloading of filling materials
|
Portion X
|
Backfilling
at Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Works for diversion
|
Airport Road
|
Establishment of site access
|
Airport Road/ Airport
Express Line/ East Coast Road
|
Finishing
works for Highway Operation and Maintenance Area Building
|
Portion X
|
Finishing
works for Scenic Hill Tunnel West Portal Ventilation building
|
West Portal
|
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 Indicator (Model No.
LD-5R)
|
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 in December 2018
is provided in Appendix D.
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
|
71
|
42 ¡V 109
|
352
|
500
|
AMS6
|
66
|
37 ¡V 93
|
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
|
53
|
36 ¡V 83
|
164
|
260
|
AMS6
|
62
|
41 ¡V 83
|
173
|
260
|
2.7.2 No Action and Limit Level exceedances of 1-hr TSP and 24-hr 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)
|
3.2.1 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
|
3.3.1
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
(d)
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.
(e)
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.
(f)
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.
(g)
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 December 2018 is provided in Appendix D.
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
|
62
|
59 ¡V 65
|
75
|
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
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 summarizes 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
|
Positioning Equipment
|
JRC DGPS 224 Model
JLR-4341 with J-NAV 500 Model NWZ4551
|
Water Depth Detector
|
Eagle Cuda-168 and
Lowrance x-4
|
Water Sampler
|
Kahlsio Water Sampler
(Vertical) 2.2 L with messenger
|
4.3.1 Table 4.3 summarizes 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, IS7, IS8, IS(Mf)9 & IS10,
Control/Far Field
Stations:
CS2 & CS(Mf)5,
Sensitive Receiver
Stations:
SR3, SR4, SR5, 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
A new water quality monitoring team has been employed for carrying out
water quality monitoring work for the Contract starting from 23 August 2017. Due
to marine work of the Expansion of Hong Kong International Airport into a
Three-Runway System (3RS Project), original locations of water quality
monitoring stations CS2, SR5 and IS10 are enclosed by works boundary of 3RS
Project. Alternative impact water quality monitoring stations, naming as
CS2(A), SR5(N) and IS10(N) was approved on 28 July 2017 and were adopted
starting from 23 August 2017 to replace the original locations of water quality
monitoring for the Contract.
4.4.3
The topographical condition of the water monitoring stations SR3 (Coordinate:
810525E, 816456N), SR4 (Coordinate: 814760E, 817867N), SR10A (Coordinate:
823741E, 823495N) and SR10B (Coordinate: 823686E, 823213N) cannot be accessed
safely for undertaking water quality monitoring. The water quality monitoring has
been temporarily conducted at alternative stations, namely SR3(N) (Coordinate
810689E, 816591N), SR4(N) (Coordinate: 814705E, 817859N) and SR10A(N)
(Coordinate: 823644E, 823484N) since 1 September 2017. The water quality
monitoring at station SR10B was temporarily conducted at Coordinate: 823683E,
823187N on 1, 4, 6, 8 September 2017 and has been temporarily fine-tuned to
alternative station SR10B(N2) (Coordinate: 823689E, 823159N) since 11 September
2017. Proposal for permanently relocating the aforementioned stations was
approved by EPD on 8 January 2018.
4.4.4
The locations of water quality monitoring stations
during the reporting period 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(N)
|
Impact Station (Close to
HKBCF construction site)
|
812942
|
820881
|
SR3(N)
|
Sensitive receivers (San
Tau SSSI)
|
810689
|
816591
|
SR4(N)
|
Sensitive receivers (Tai
Ho Inlet)
|
814705
|
817859
|
SR5(N)
|
Sensitive Receivers
(Artificial Reef in NE Airport)
|
812569
|
821475
|
SR10A(N)
|
Sensitive receivers (Ma
Wan Fish Culture Zone)
|
823644
|
823484
|
SR10B(N2)
|
Sensitive receivers (Ma
Wan Fish Culture Zone)
|
823689
|
823159
|
CS2(A)
|
Control Station (Mid-Ebb)
|
805232
|
818606
|
CS(Mf)5
|
Control Station
(Mid-Flood)
|
817990
|
821129
|
Remarks:
1) A vessel moored at IS10(N) during ebb tide monitoring period
on 5 Dec 2018. The water quality monitoring at station IS10(N)(coordinate:
820881N, 812942E) was temporarily conducted at a location which is close to
the original coordinates of station IS10(N) as far as practicable based on
safety consideration during ebb tide on 5 Dec 2018.
2) Metal beam across Tai
Ho Inlet blocked the access of station SR4(N)(coordinates: 817859N, 814705E)
in all water monitoring date of December 2018. Also, a rope connecting silt
curtains in the sea on 10, 12 and 14 December 2018 and silt curtains
deployment on 17 Dec 2018 were observed respectively. The access to SR4(N)
have been further blocked by silt curtains since 17 Dec 2018. As such, the
water quality monitoring at station SR4(N) was temporarily conducted at a
location which is close to the original coordinates of station SR4(N) as far
as practicable in December 2018.
|
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 December 2018 is provided in Appendix D.
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
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.
4.7.3 For marine water quality monitoring, no
Action Level and Limit Level exceedances of dissolved oxygen level and
turbidity level were recorded during the reporting month.
4.7.4 During the reporting month, two Action
Level exceedances of suspended solids level were recorded. No Limit Level
exceedances of suspended solids level were recorded.
4.7.5 Number of exceedances recorded
during the reporting month at each impact station are summarized 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
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
12-12-2018
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS(Mf)6
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS7
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS8
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS(Mf)9
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
12-12-2018
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS10(N)
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR3(N)
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR4(N)
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR5(N)
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10A(N)
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10B(N2)
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Total
|
Action
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
2
|
2**
|
Limit
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0**
|
Notes:
S: Surface;
M: Mid-depth;
** The
total number of
exceedances
4.7.6
The exceedances suspended solid
level recorded during reporting period were considered to be attributed to
other external factors such as sea condition, rather than the contract works.
Therefore, the exceedances were considered as non-contract related. Records of
¡§Notification of Environmental Quality Limit Exceedances¡¨ are provided in Appendix N.
4.7.7 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
requirement of the updated EM&A manual, dolphin monitoring programme should
cover all transect lines in NEL and NWL survey areas (see Figure 1 of Appendix H) twice per
month throughout the entire construction period. The co-ordinates of all transect lines
are shown in Table 5.2. The coordinates of several starting and ending points
have been revised due to the presence of a work zone to the north of the
airport platform with intense construction activities in association with the
construction of the third runway expansion for the Hong Kong International
Airport. The EPD issued a memo and
confirmed that they had no objection on the revised transect lines on 28 July
2017, 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
|
805476
|
820800*
|
|
14
|
Start Point
|
817537
|
820220
|
2
|
End Point
|
805476
|
826654
|
|
14
|
End Point
|
817537
|
824613
|
3
|
Start Point
|
806464
|
821150*
|
|
15
|
Start Point
|
818568
|
820735
|
3
|
End Point
|
806464
|
822911
|
|
15
|
End Point
|
818568
|
824433
|
4
|
Start Point
|
807518
|
821500*
|
|
16
|
Start Point
|
819532
|
821420
|
4
|
End Point
|
807518
|
829230
|
|
16
|
End Point
|
819532
|
824209
|
5
|
Start Point
|
808504
|
821850*
|
|
17
|
Start Point
|
820451
|
822125
|
5
|
End Point
|
808504
|
828602
|
|
17
|
End Point
|
820451
|
823671
|
6
|
Start Point
|
809490
|
822150*
|
|
18
|
Start Point
|
821504
|
822371
|
6
|
End Point
|
809490
|
825352
|
|
18
|
End Point
|
821504
|
823761
|
7
|
Start Point
|
810499
|
822000*
|
|
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
|
821176
|
|
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
|
|
24*
|
Start Point
|
805476*
|
815900*
|
12
|
End Point
|
815542
|
824882
|
|
24*
|
End Point
|
805476*
|
819100*
|
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 20
years of marine mammal monitoring surveys in Hong Kong developed by HKCRP (see
Hung 2017). 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 traveled 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 camera (Canon EOS 7D model), 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 December 2018, two sets of systematic
line-transect vessel surveys were conducted on the 3rd, 5th, 10th
and 12th 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
261.96 km of survey effort was collected, with
90.3%
of the total survey effort being conducted under favourable weather conditions (i.e. Beaufort Sea State 3 or
below with good visibility) (Annex I of Appendix H).
5.3.3
Among the two
survey areas, 97.00
km and 164.96
km of survey effort were collected from
NEL and NWL survey areas respectively. Moreover,
the total survey effort conducted on primary lines was
193.46 km, while the effort on secondary lines
was 68.50 km.
5.3.4
During the two sets of monitoring surveys in December
2018, two groups of
six Chinese White Dolphins were sighted
(see Annex
II of Appendix H). Both dolphin sightings were all made
in NWL, while none was sighted in NEL.
5.3.5
Moreover, both dolphin groups were sighted
on primary lines during on-effort search (Annex II of Appendix
H). Notably,
none of the dolphin groups
was associated with any
operating fishing vessel.
5.3.6
Distribution of the
two dolphin sightings
made in December 2018 is
shown in Figure
6 of Appendix H. They were sighted to the west of Lung
Kwu Chau and near Lung Kwu Tan respectively (Figure
6 of Appendix H).
5.3.7
During the December¡¦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 Tables 5.3 and 5.4.
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: December 3rd / 5th
|
0.0
|
0.0
|
Set
2: December 10th / 12th
|
0.0
|
0.0
|
NWL
|
Set
1: December 3rd / 5th
|
4.0
|
11.9
|
Set
2: December 10th / 12th
|
0.0
|
0.0
|
Remark:
1. Dolphin Encounter Rates Deduced from the Two
Sets of Surveys (Two Surveys in Each Set) in December 2018 in Northeast Lantau
(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
|
1.9
|
1.4
|
5.7
|
4.3
|
Remark:
1.
Monthly Average Dolphin Encounter Rates (Sightings Per 100 km of
Survey Effort) from All Four Surveys Conducted in December 2018 on Primary Lines only as well as Both Primary
Lines and Secondary Lines in Northeast Lantau (NEL) and Northwest Lantau (NWL).
5.3.8
As there were only two groups of one and five dolphins
being sighted respectively, the average dolphin group size in December 2018 was just three individuals
per group, which was much lower than the averages in the previous monitoring
months (Annex II of Appendix H).
Photo-identification Work
5.3.9
Three known individual dolphins were sighted three times in total during
the December¡¦s surveys (Annexes III and
V of Appendix H). All three individuals were re-sighted
only once during the monthly surveys. Notably,
during their re-sightings in December 2018, none of the identified individuals
was sighted with any young calf.
Conclusion
5.3.10
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.
5.3.11
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 (December
2018 ¡V February 2019) and the 3-month baseline monitoring period will be made.
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. 2017. Monitoring of Marine Mammals in Hong
Kong waters: final report (2016-17).
An unpublished report submitted to the Agriculture, Fisheries and
Conservation Department, 162 pp.
5.4.3 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 1 December 2018. 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
(December 2018)
|
Monitoring
Station
|
Easting
(m)
|
Northing
(m)
|
Surface
Level
(mPD)
|
Easting
(m)
|
Northing
(m)
|
Surface
Level
(mPD)
|
S1
|
810291.160
|
816678.727
|
0.950
|
810291.177
|
816678.732
|
1.120
|
S2
|
810958.272
|
815831.531
|
0.864
|
810958.261
|
815831.516
|
0.974
|
S3
|
810716.585
|
815953.308
|
1.341
|
810716.572
|
815953.312
|
1.476
|
S4
|
811221.433
|
816151.381
|
0.931
|
811221.425
|
816151.415
|
1.121
|
Table 6.3 Comparison
of measurement
|
Comparison of measurement
|
Remarks
and Recommendation
|
Monitoring Station
|
Easting (m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
0.017
|
0.005
|
0.170
|
Level continuously increased
|
S2
|
-0.011
|
-0.015
|
0.110
|
Level continuously increased
|
S3
|
-0.013
|
0.004
|
0.135
|
Level continuously increased
|
S4
|
-0.008
|
0.034
|
0.190
|
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(N)) as in the EM&A Manual.
The water quality monitoring location (SR3(N)) is shown in Figure 2.1.
6.2.2 Impact water quality
monitoring in San Tau (monitoring station SR3(N)) was conducted in December 2018.
The monitoring parameters included dissolved oxygen (DO), turbidity and
suspended solids (SS).
6.2.3 The Impact
monitoring results for SR3(N) 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)
|
03-Dec-2018
|
6.8
|
4.4
|
7.1
|
6.7
|
11.8
|
13.2
|
05-Dec-2018
|
6.8
|
4.0
|
5.9
|
6.8
|
11.4
|
15.3
|
07-Dec-2018
|
6.7
|
3.4
|
6.4
|
6.9
|
2.3
|
6.4
|
10-Dec-2018
|
7.2
|
3.6
|
5.7
|
6.6
|
5.2
|
11.0
|
12-Dec-2018
|
7.1
|
5.5
|
9.1
|
7.5
|
7.3
|
12.3
|
14-Dec-2018
|
6.7
|
2.6
|
5.0
|
7.4
|
5.7
|
10.4
|
17-Dec-2018
|
7.6
|
2.1
|
3.0
|
7.2
|
2.4
|
4.2
|
19-Dec-2018
|
7.4
|
3.4
|
4.4
|
7.2
|
3.9
|
7.0
|
21-Dec-2018
|
7.1
|
2.6
|
5.8
|
6.7
|
4.2
|
7.4
|
24-Dec-2018
|
7.2
|
4.8
|
8.6
|
7.3
|
3.6
|
6.4
|
26-Dec-2018
|
6.7
|
5.7
|
7.5
|
6.9
|
3.7
|
7.5
|
28-Dec-2018
|
6.8
|
5.4
|
7.5
|
7.1
|
7.5
|
8.6
|
31-Dec-2018
|
7.7
|
2.7
|
5.2
|
7.6
|
6.1
|
8.8
|
Average
|
7.1
|
3.8
|
6.2
|
7.1
|
5.8
|
9.1
|
|
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 shoreline of sampling
zones TC1, TC2, TC3 and ST were about 250 m, 300 m, 300 m and 250 m
respectively (Figure 2.2 of Appendix I).
Survey of horseshoe crabs, seagrass beds and intertidal communities were
conducted in every sampling zone. The present survey was conducted in December
2018 (totally 5 sampling days between 1st and 16th December
2018).
6.3.2
Since the field survey of Jun.
2016, increasing number of trashes and even big trashes (Figure 2.3 of Appendix I) were found in every sampling zone. It raised a concern about the
solid waste dumping and current-driven waste issues in Tung Chung Wan.
Respective measures (e.g. manual clean-up) should be implemented by responsible government agency
units.
Horseshoe Crabs
6.3.3
Active search method was conducted for horseshoe crab monitoring by two experienced surveyors in every sampling zone.
During the search period, any accessible and potential area would be
investigated for any horseshoe crab individuals within 2-3 hours of 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 1st (for TC3), 2nd (for TC1), 11th
(for ST) and 15th (for TC2) December 2018. The weather was warm and
sunny on first two survey days (1st and 2nd Dec.) while
it was cold and cloudy on the following days (11th and 15th
Dec).
6.3.4
In Jun. 2017, a big horseshoe
crab was tangled by a trash gill net in ST mudflat (Figure 2.3 of Appendix I). It was released to sea once after photo recording. The horseshoe
crab of such size should be inhabiting sub-tidal environment while it forages
on intertidal shore occasionally during high tide period. If it is tangled by
the trash net for few days, it may die due to starvation or overheat during low
tide period. These trash gill nets are definitely ¡¥fatal trap¡¦ for the
horseshoe crabs and other marine life. Manual clean-up should be implemented as
soon as possible by responsible government agency units.
Seagrass Beds
6.3.5
Active search method was conducted for seagrass bed monitoring by two
experienced surveyors in every sampling zone. During the
search period, any accessible and potential area would be investigated for any
seagrass beds within 2-3 hours of low tide period. Once seagrass
bed was found, the species, estimated area, estimated coverage percentage
and respective GPS coordinates were recorded.
The seagrass beds surveys were conducted on 1st (for TC3), 2nd
(for TC1), 11th (for ST) and 15th (for TC2) December 2018.
The weather was warm and sunny on first two survey days (1st and 2nd
Dec.) while it was cold and cloudy on the following days (11th and
15th Dec.).
Intertidal Soft Shore Communities
6.3.6 The intertidal soft shore
community surveys were conducted in low tide period on 1st (for TC3),
2nd (for TC1), 15th (for TC2) and 16th (for ST)
December 2018. In every sampling zone, three 100 m horizontal transect lines 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 line, ten random quadrats
(0.5 m x 0.5 m) were placed.
6.3.7 Inside a quadrat, any visible epifauna were collected
and were in-situ identified to the
lowest practical taxonomical resolution. Whenever possible a hand core sample (10 cm internal diameter ´ 20 cm depth) of sediments was collected in the quadrat. The core sample was gently washed through a sieve of mesh size 2.0 mm in-situ. Any visible infauna were collected and identified. Finally
the top 5 cm surface sediments was dug for visible infauna in the quadrat
regardless of hand core sample was taken.
6.3.8 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.
6.3.9 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), AFCD (2018).
Data Analysis
6.3.10 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 the
present survey, two species of horseshoe crab (total 15 ind.) and Tachypleus tridentatus (total 13 ind.) were recorded. The recorded individuals were mainly
distributed along the shoreline from TC3 to ST. Grouping of 2-3 individuals was
usually observed on
similar substratum (fine sand or soft mud, slightly submerged).Photo
records were shown in Figure 3.1 of Appendix I while the complete survey records were
listed in Annex II of Appendix I.
6.5.2
Table 3.1 of
Appendix I summarizes the
survey results of horseshoe crab in the present survey. In general, very low search record was found for both species in
TC1, TC3 and ST. No individual of either species was found in TC2.
6.5.3
For Carcinoscorpius rotundicauda, more individuals (10 ind.) were
found in TC3 with average body size 36.34 mm (19.25-71.23 mm). In TC1, there were 4 individuals with average
body size 38.39 mm (prosomal width ranged 23.24-58.44 mm). In ST, there was only 1 individual
with body size 61.20 mm. The three zones were very low in search record (0.2-1.7
ind. hr-1 person-1).
6.5.4
There was similar pattern of survey results for Tachypleus tridentatus. Relatively more individuals were found in TC3 (7 ind.) with average body
size 34.90 mm (26.30-38.73
mm).
In TC1 and ST, there were only 3 individuals with average body size 47.06-49.13
mm (prosomal width ranged 37.37-66.72 mm). The search record was very low (0.5-1.2 ind. hr-1 person-1) for the three zones.
6.5.5
Based on previous monitoring results, there
were similar searach records of horseshoe crab in TC3 and ST. But it was
relatively higher in TC3 in present survey because the survey was conducted
under warmer weather in early December. The survey for ST was conducted in mid
December while the ambient temperature dropped significantly. It could decrease
the activity rate of horseshoe crab.
6.5.6
In the survey of Mar. 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). It indicated the importance of ST as a breeding ground of horseshoe crab. In Jun. 2017, mating pairs of Carcinoscorpius
rotundicauda were also found in TC2 (male 175.27 mm, female 143.51 mm) and
TC3 (male 182.08 mm, female 145.63 mm) (Figure 3.2 of Appendix I). In Dec. 2017 and Jun. 2018 , one mating pair was of Carcinoscorpius
rotundicauda was found in TC3 (Dec. 2017: male 127.80 mm, female 144.61 mm; Jun. 2018: male 139 mm, female 149 mm). Figure
3.2 of Appendix I shows the photographic records of all mating pairs found. The recorded mating pairs were found nearly burrowing in soft mud at
low tidal level (0.5-1.0 m above C.D.). The smaller male was holding the
opisthosoma (abdomen carapace) of larger female from behind. These mating pairs indicated that
breeding of horseshoe crab could be possible along the coast of Tung Chung Wan
rather than ST only, as long as suitable substratum was available. Based on the frequency of encounter, the shoreline between TC3 and
ST should be more suitable mating ground. Moreover suitable breeding period was believed in wet season (Mar -
Sep.) because tiny individuals (i.e. newly hatched) were usually recorded in
Jun. and Sep. every year.
6.5.7
Despite of mating pair, there
were occasional records of large individuals of Carcinoscorpius rotundicauda (prosomal width ranged 114.45 - 178.67 mm, either single or in
pair) and Tachypleus tridentatus (prosomal
width 103 mm) (Figure
3.3 of Appendix I). In the present survey (Dec. 2018), one large individual of Carcinoscorpius rotundicauda was found in TC3 (prosomal width 148.94 mm). Based
on their sizes, it indicated that individuals of prosomal width larger than 100
mm would progress its nursery stage from intertidal habitat to sub-tidal
habitat of Tung Chung Wan. These large individuals might move onto intertidal
shore occasionally during high tide for foraging and breeding. Because they should be inhabiting sub-tidal habitat most of the time.
Their records were excluded from the data analysis to avoid mixing up with
juvenile population living on intertidal habitat.
6.5.8 No marked individual of horseshoe crab was
recorded in the present survey. Some marked individuals were found in the
previous surveys of Sep. 2013, Mar. 2014 and Sep. 2014. All of them were
released through a conservation programme in charged 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 crab 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 Sep.
2014.
6.5.9 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
6.5.10 Figures 3.5 and 3.6 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 throughout the monitoring period.
6.5.11 For TC3 and ST, medium to high
search records (i.e. number of individuals) of both species were always found
in wet season (Jun. and Sep.). The search record of ST was higher from Sep. 2012
to Jun. 2014 while it was replaced by TC3 from Sep. 2014 to Jun. 2015. The
search records were similar between two sampling zones from Sep. 2015 to Jun.
2016. In Sep. 2016, the search record of Carcinoscorpius
rotundicauda in ST was much higher than TC3. From Mar. to Jun. 2017, the
search records of both species were similar again between two sampling zones.
It showed a natural variation of horseshoe crab population in these two zones
due to weather condition and tidal effect. No obvious
difference of horseshoe crab population was noted between TC3 and ST. In Sep.
2017, the search records of both horseshoe crab species decreased except the Carcinoscorpius rotundicauda in TC3. The survey results were different from previous findings that
there were usually higher search records in September. One possible reason was
that the serial cyclone hit decreased horseshoe crab activity (totally 4
cyclone records between Jun. and Sep. 2017, to be discussed in 'Seagrass
survey' section). From Dec. 2017 to Sep. 2018, the
search records of both species increased again to low-moderate level in ST. Relatively higher population fluctuation of Tachypleus tridentatus was observed in TC3.
6.5.12 For TC1, the search record was at low to moderate level throughout the
monitoring period. The change of Carcinoscorpius rotundicauda was relatively more variable than that of Tachypleus tridentatus. Relatively, the search record
was very low in TC2. There were occasional records of 1 to 4 individuals
between March and September throughout the monitoring period. The maximum
record was 6 individuals only in Jun. 2016.
6.5.13 About
the body size, larger individuals of Carcinoscorpius rotundicauda were usually found in ST and TC1 relative to those in TC3 from Sep. 2012
to Jun. 2017. But the body size was higher in TC3 and ST followed by TC1 from
Sep. 2017 to Jun. 2018. In Sep. 2018, larger individuals were found in ST and
TC1 again. For Tachypleus
tridentatus, larger individuals were usually found
in ST and TC3 followed by TC1 throughout the monitoring period.
6.5.14 In general, it was obvious that the
shoreline along 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 foraging area due to limited area of suitable substratum.
Although a mating pair of Carcinoscorpius rotundicauda was once found in TC2, the hatching rate and survival rate of newly
hatched individuals were believed very low.
Seasonal
variation of horseshoe crab population
6.5.15
Throughout the monitoring period, the search
record of horseshoe crab declined obviously during dry season especially
December (Figures 3.4 and 3.5 of Appendix I). Very low ¡V low search record was
found in December from 2012 to 2015 (0-4 ind. of Carcinoscorpius rotundicauda and 0-12 ind. of Tachypleus tridentatus). 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).
Relatively the search records were much higher in Dec. 2016. There were totally 70
individuals of Carcinoscorpius rotundicauda and 24 individuals of Tachypleus tridentatus in TC3 and ST. Because the survey was arranged in early December
while the weather was warm with sunlight (~22 ¢XC during dawn according to Hong
Kong Observatory database, Chek Lap Kok station on 5 Dec.). In contrast, there was no search record in TC1 and TC2 because the
survey was conducted in mid December with colder and cloudy weather (~20 ¢XC during dawn on 19 Dec.). The horseshoe crab activity would decrease gradually with the colder climate. In December
of 2017 and 2018 (present survey), very low search records were found again as
mentioned above.
6.5.16
From Sep. 2012 to Dec. 2013, Carcinoscorpius rotundicauda was a less
common species relative to Tachypleus
tridentatus. Only 4 individuals were ever recorded in ST in Dec. 2012. This species
had ever been believed of very low density in ST hence the encounter rate was
very low. In Mar. 2014, it was found in all sampling zones with higher
abundance in ST. Based on its average size (mean prosomal width 39.28-49.81
mm), it indicated that breeding and spawning of this species had occurred 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. Since Mar. 2014, more individuals
were recorded due to larger size and higher activity (i.e. more conspicuous
walking trail).
6.5.18 Recently, Carcinoscorpius rotundicauda was a more common horseshoe crab
species in Tung Chung Wan. It was recorded in the four sampling zones while the
majority of population located in TC3 and ST. Due to potential breeding last
year, Tachypleus
tridentatus became common again and distributed in
TC3 and ST mainly. Since TC3 and ST were regarded as important nursery ground for both
horseshoe crab species, 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
6.5.19
Figure 3.7 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 Sep.
2012 and Dec. 2013 hence the data were lacking. In Mar 2014, the major size (50% of individual records
between upper (top of red box) and lower quartile (bottom of blue box)) ranged
40-60 mm while only few individuals were found. From Mar. 2014 to Sep. 2018,
the median prosomal width (middle line of whole box) and major size (whole box)
decreased after Mar. of every year. It was due to more small individuals found
in June indicating new rounds of spawning. Also, there were slight
increasing trends of body size from Jun. to Mar. of next year since 2015. It
indicated a stable growth of individuals. Focused on larger juveniles (upper
whisker), the size range was quite variable (prosomal width 60-90 mm) along the
sampling months. Juveniles reaching this size might gradually migrate to
sub-tidal habitats.
6.5.20 For Tachypleus
tridentatus, the major size ranged
20-50 mm while the number of individuals fluctuated from Sep. 2012 to Jun.
2014. Then a slight but consistent growing trend was observed from Sep. 2014 to
Jun. 2015. The prosomal width increased from 25-35 mm to 35-65 mm. 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. From Mar. to Sep. 2016, slight increasing trend of major
size was noticed again. From Dec. 2016 to Jun. 2017, similar increasing trend
of major size was noted with much higher number of individuals. It reflected
new round of spawning. In Sep. 2017, the major size decreased while the trend
was different from previous two years. Such decline might be the cause of
serial cyclone hit between Jun. and Sep. 2017 (to be discussed in the 'Seagrass
survey' section). From Dec. 2017 to Sep. 2018, increasing trend was noted
again. Across the whole monitoring period, the
larger juveniles (upper whisker) usually reached 60-80 mm in prosomal width,
even 90 mm occasionally. Juveniles reaching this size might gradually migrate
to sub-tidal habitats.
Box plot of horseshoe crab populations in ST
6.5.21
Figure 3.8 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 Sep. 2012 and Dec. 2013 hence the data were
lacking. From Mar. 2014 to Sep. 2018, the size of major population decreased and more small individuals (i.e.
lower whisker) were recorded after Jun. of every year. It indicated new
round of spawning. Also there were similar increasing trends of body size from
Sep. to Jun. of next year between 2014 and 2017. It indicated a stable growth
of individuals. Across the whole monitoring period, the larger juveniles (i.e. upper whisker) usually
ranged 60-80 mm in prosomal width except one individual (prosomal width 107.04 mm) found in
Mar. 2017. It reflected juveniles reaching this size would gradually migrate to
sub-tidal habitats.
6.5.22
For Tachypleus tridentatusa, a consistent growing trend was observed for the major population
from Dec. 2012 to Dec. 2014 regardless of change of search record. The prosomal
width increased from 15-30 mm to 60-70 mm. As mentioned, the large juveniles might have reached a suitable
size for migrating from the nursery soft shore to subtidal habitat. From Mar.
to Sep. 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 juveniles might have migrated to
sub-tidal habitat, leaving the smaller individuals on shore. There was an
overall growth trend. In Dec. 2015, two big individuals (prosomal width 89.27
mm and 98.89 mm) were recorded only while it could not represent the major
population. In Mar. 2016, the number of individual was very few in ST that no
boxplot could be produced. In Jun. 2016, the prosomal width of major population
ranged 50-70 mm. But it dropped clearly to 30-40 mm in Sep. 2016 followed by an
increase to 40-50 mm in Dec. 2016, 40-70 mm in Mar. 2017 and 50-60mm in Jun.
2017. Based on overall higher number of small individuals from Jun. 2016 to
Sep. 2017, it indicated another round of spawning. From Sep. 2017 to Jun. 2018,
the major size range increased slightly from 40-50 mm to 45-60 mm indicating a
continous growth. In Sep. 2018, decrease of major size was noted again that
might reflect new round of spawning. Throughout the monitoring period, the
larger juveniles ranged 60-80 mm in prosomal width. Juveniles reaching this
size would gradually migrate to sub-tidal habitats.
6.5.23 As a summary for horseshoe crab
populations in TC3 and ST, there were spawning of Carcinoscorpius rotundicauda from 2014 to 2018 while the spawning
time should be in spring. The population size was consistent in these two sampling zones. For Tachypleus tridentatus, small individuals were rarely found in both zones 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. From 2016 to 2018, new rounds of spawning were recorded in ST while
the population size increased to a moderate level.
Impact of the HKLR project
6.5.24 It was
the 25th survey of the EM&A programme during the construction period. Based on the monitoring results,
impact of the HKLR project was not detected on horseshoe crabs. The population
change was mainly determined by seasonal variation while new rounds of spawning were observed for both species. Abnormal phenomenon (e.g. very few numbers of horseshoe crab individuals in wet season, large number of dead individuals on the shore)
had not been reported.
Seagrass Beds
6.5.25 Since the commencement of the
EM&A monitoring programme, two species of seagrass Halophila ovalis and Zostera japonica were recorded in TC3 and ST (Figure 3.9 of Appendix I). In general Halophila ovalis was occasionally found in TC3
in few, small to medium patches. But it was commonly found in ST in medium to
large seagrass bed. Moreover it had sometimes grown extensively and had covered
significant mudflat area at 0.5-2.0 m above C.D. between TC3 and ST. Another seagrass species Zostera
japonica was found in ST only. It was
relatively lower in vegetation area and was co-existing with Halophila ovalis nearby the mangrove strand at
2.0 m above C.D..
6.5.26 Table 3.2 of Appendix I summarizes the
results of present seagrass beds survey.
Seagrass beds were found in ST
only. There were two low-medium sized, horizontal strands of Halophila ovalis with total seagrass bed area ~ 404 m2 (Figure 3.10 of Appendix I). The
larger strand had area ~264 m2 in medium-high vegetation coverage 50-85%, located at tidal zone
1.5-2.0 m above C.D nearby mangrove plantation. At close vicinity, there was a smaller
horizontal strand (~140 m2, low coverage 5-20%). Another
seagrass species Zostera japonica was not found in present survey.
Annex III of Appendix I shows the
complete record of seagrass survey.
6.5.27 According to the previous results, majority of seagrass bed was confined
in ST, the temporal change of both seagrass species were investigated in
details:
Temporal
variation of seagrass beds
6.5.28 Figure
3.11 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 Mar. 2013 that grew within the large
patch of seagrass Halophila
ovalis. Then the patch size
increased and merged gradually with the warmer climate from Mar. to Jun. 2013
(15 m2). However the patch size decreased and remained similar from
Sep. 2013 (4 m2) to Mar. 2014 (3 m2). In Jun. 2014, the
patch size increased obviously again (41 m2) with warmer climate
followed by a decrease between Sep. 2014 (2 m2) and Dec. 2014 (5 m2).
From Mar. to Jun. 2015, the patch size increased sharply again (90 m2).
It might be due to the disappearance of the originally dominant seagrass Halophila ovalis resulting in less competition
for substratum and nutrients. From Sep. 2015 to Jun. 2016, it was found
coexisting with seagrass Halophila ovalis with steady increasing patch
size (from 44 m2
to 115 m2) and variable coverage. In Sep. 2016, the patch size decreased
again to (38 m2) followed by an increase to a horizontal strand (105.4 m2) in Jun. 2017. And it
was no longer co-existing with Halophila ovalis. Between Sep. 2014 and Jun. 2017, an
increasing trend was noticed from Sep. to Jun. of next year followed by a rapid
decline in Sep. of next year. It was possibly the causes of heat stress,
typhoon and stronger grazing pressure during wet season. However such
increasing trend was not found from Sep. 2017 to Dec. 2018 (present survey)
while no patch of Zostera
japonica was found.
6.5.29 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 Sep. 2012
(first survey). The total
seagrass bed area grew steadily from 332.3 m2 in Sep. 2012 to 727.4
m2 in Dec. 2013. Flowers were observed in the largest patch during its
flowering period. In Mar.
2014, 31 small to medium patches were newly recorded (variable area 1-72 m2
per patch, vegetation coverage 40-80% per patch) in lower tidal zone between
1.0 and 1.5 m above C.D. The total seagrass area increased further to 1350 m2.
In Jun. 2014, these small and medium patches grew and extended to each other.
These patches were no longer distinguishable and were covering a significant
mudflat area of ST. It was generally grouped into 4 large patches (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 Sep. 2014, the total seagrass area
declined sharply to 1111 m2. There were only 3-4 small to large
patches (6-253 m2) at high tidal level and 1 large patch at low
tidal level (786 m2). Typhoon or strong water current
was a possible cause
(Fong, 1998). In Sep. 2014, there were two tropical cyclone records in Hong
Kong (7th-8th Sep.: no cyclone name, maximum signal
number 1; 14th-17th Sep.: Kalmaegi, maximum signal number
8SE) before the seagrass survey dated 21st Sep. 2014. The strong
water current caused by the cyclone, Kalmaegi especially, might have given
damage to the seagrass beds. In addition, natural heat stress and grazing force
were other possible causes reducing seagrass beds area. Besides, very small
patches of Halophila
ovalis could be found in other
mud flat area in addition to the recorded patches. But it was hardly
distinguished due to very low coverage (10-20%) and small leaves.
6.5.30 In
Dec. 2014, all the seagrass patches of Halophila
ovalis disappeared in ST. Figure 3.12
of Appendix I shows the difference of the original seagrass beds area nearby the
mangrove vegetation at high tidal level between Jun. 2014 and Dec. 2014. Such
rapid loss would not be seasonal phenomenon because the seagrass beds at higher
tidal level (2.0 m above C.D.) were present and normal in December 2012 and
2013. According to Fong (1998), similar incident had occurred in ST in the
past. The original seagrass area had declined significantly during the
commencement of the construction and reclamation works for the international
airport at Chek Lap Kok in 1992. The seagrass almost disappeared in 1995 and
recovered gradually after the completion of reclamation works. Moreover,
incident of rapid loss of seagrass area was also recorded in another intertidal
mudflat in Lai Chi Wo in 1998 with unknown reason. Hence Halophila ovalis was regarded as a short-lived
and r-strategy seagrass that could
colonize areas in short period but disappears quickly under unfavourable
conditions (Fong, 1998).
Unfavourable conditions to seagrass Halophila
ovalis
6.5.31 Typhoon or strong water current was suggested as one unfavourable
condition to Halophila ovalis (Fong,
1998). As mentioned above, there were two tropical cyclone records in Hong Kong
in Sep. 2014. The strong water current caused by the cyclones might have given
damage to the seagrass beds.
6.5.32
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).
6.5.33
In order to investigate any
deterioration of water quality (e.g. more turbid) in ST, the water quality
measurement results at two closest monitoring stations SR3 and IS5 of the
EM&A programme were obtained from the water quality monitoring team. Based
on the results from June to December 2014, the overall water quality was in
normal fluctuation except there was one exceedance of suspended solids (SS) at
both stations in September. On 10th Sep., 2014, the SS
concentrations measured during 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 Sep. 2014 (daily total
rainfall at the Hong Kong International Airport: 0-2.1 mm; extracted from the
climatological data of Hong Kong Observatory). The effect of upstream runoff on
water quality should be neglectable in that period. Moreover, the exceedance of
water quality was considered unlikely to be related to the contract works of
HKLR according to the ¡¥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.
6.5.34
Based on the weather condition and water
quality results in ST, the co-occurrence of cyclone hit and turbid waters in Sep. 2014 might
have combined the adverse effects on Halophila ovalis that leaded to disappearance of
this short-lived and r-strategy
seagrass species. Fortunately, Halophila
ovalis was a fast-growing
species (Vermaat et al., 1995). Previous studies showed that the
seagrass bed could be recovered to the original sizes in 2 months through
vegetative propagation after experimental clearance (Supanwanid, 1996).
Moreover, it was reported to recover rapidly in less than 20 days after dugong
herbivory (Nakaoka and Aioi, 1999). As mentioned, the disappeared seagrass in
ST in 1995 could recover gradually after the completion of reclamation works
for international airport (Fong, 1998). The seagrass beds of Halophila ovalis might recolonize the mudflat of ST through seed reproduction as long
as there was no unfavourable condition in the coming months.
Recolonization of seagrass beds
6.5.35
Figure 3.12 of Appendix I shows the recolonization of seagrass bed area in ST from Dec. 2014 to Jun.
2017. From Mar. to Jun. 2015, 2-3 small patches of Halophila ovalis were
newly found co-inhabiting 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
Dec. 2014 and Mar. 2015. Moreover, it would need to compete with seagrass Zostera japonica for substratum and nutrient. Since Zostera japonica had extended and had covered the original seagrass bed of Halophila ovalis at certain degree. From Jun.
2015 to Mar. 2016, the total seagrass area of Halophila ovalis had increased rapidly
from 6.8 m2 to 230.63 m2. It had recolonized its
original patch locations and covered Zostera
japonica. In Jun. 2016, the total seagrass area increased sharply to 4707.3 m2. Similar to the previous records of Mar to Jun. 2014, the original
patch area increased further to a horizontally long strand. Another large
seagrass beds colonized the lower
tidal zone (1.0-1.5 m above C.D.). In Sep. 2016, this patch extended much and
covered significant soft mud area of ST, resulting in sharp increase of total area
(24245 m2). It indicated the second extensive colonization of this r-selected seagrass. In Dec. 2016, this
extensive seagrass patch decreased in size and had separated into few, undistinguishable patches. Moreover, the
horizontal strand nearby the mangrove vegetation decreased in size. The total
seagrass bed decreased to 12550 m2. From Mar. to Jun. 2017, the
seagrass bed area remained generally stable (12438-17046.5 m2) but
the vegetation coverage fluctuated (20-50% in Mar. 2017 to 80-100% in Jun. 2017).
The whole recolonization process took about 2.5 years.
Re-disappearance of seagrass bed
6.5.36
In Sep 2017, the whole seagrass
bed of Halophila ovalis disappeared
again along the shore of TC3 and ST (Figure
3.12 of Appendix I). It was similar to the case between Sep. and Dec. 2014. As
mentioned, strong water current (e.g. cyclone) or deteriorated water quality
(e.g. high turbidity) were the possible causes.
6.5.37
Between the survey periods of
Jun. and Sep. 2017, there were four tropical cyclone records in Hong Kong
(Merbok in 12-13th, Jun.; Roke in 23rd, Jul.; Hato in
22-23rd, Aug.; Pakhar in 26-27th, Aug.) (online database
of Hong Kong Observatory). All of them reaches signal 8 or above especially
Hato (highest signal 10).
6.5.38
According to the water quality
monitoring results (Jul. to Aug. 2017) of the two closest monitoring stations
SR3 and I5 of the respective EM&A programme, the overall water quality was
in normal fluctuation. There was one exceedance of suspended solids (SS) at SR3
on 12 Jul. 2017. The SS concentration reached 24.7 mg/L during mid-ebb tide. It
exceeded the Action Level (≤23.5 mg/L) but was far below the Limit Level (≤34.4 mg/L). Since such exceedance was slight
and temporary, its effect to seagrass bed should be minimal.
6.5.39
Overall, the disappearance of
seagrass beds in ST was believed the cause of serial cyclone hit in Jul and
Aug. 2017. Based on previous findings, the seagrass beds of both species were
expected to recolonize the mudflat as long as the vicinal water quality was
normal. The whole recolonization process (from few, small patches to extensive
strand) would be gradual lasting minimum 2 years. From Dec. 2017 to Mar. 2018,
there was still no recolonization of few, small patches of seagrass at the
usual location (Fig. 3.12). It was different from previous round (Mar. 2015 -
Jun. 2017). Until Jun. 2018, new, small-medium seagrass patches were found at
the usual location (seaward side of mangrove plantation at 2.0 m C.D.) again,
indicating the recolonization. However the seagrass bed area decreased sharply to
22.5 m2 in Sep. 2018. Again it was believed the hit of super cyclone
in Sep. 2018 (Mangkhut on 16th Sep., highest signal
10). In Dec. 2018 (present survey), the seagrass bed area increased again.
Relatively, it would occour later and slower than
previous round (more than 2 years).
Impact of the HKLR
project
It was the 25th survey of the EM&A
programme during the construction period. Throughout the monitoring period, the disappearance of seagrass beds was
believed the cause of cyclone hits rather than impact of HKLR project. There
was slow and gradual recolonization in the following
dry season.
Intertidal Soft Shore Communities
6.5.40 Table 3.3 and Figure 3.13 of Appendix I show the substratum types along the horizontal
transct at every tidal level in all sampling zones. The
relative distribution of substratum types 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 percentages of ¡¥Gravels and Boulders¡¦ (80-90%) were
recorded at high and mid tidal levels. Relatively higher percentages of ¡¥Gravels
and Boulders¡¦ (40%) and ¡¥Soft mud¡¦ (40%) were recorded at low tidal level.
¡P
In TC2, higher percentage of ¡¥Sands¡¦ (60%) was recorded at high tidal
level. At mid tidal level, there was higher percentage of ¡¥Soft mud¡¦ (60%)
followed by ¡¥Gravels and Boulders¡¦ (40%). At low tidal level, the major
substratum type was 'Soft mud' (80%).
¡P
In TC3, higher percentage of ¡¥Sands¡¦ (70%) was recorded followed by
¡¥Soft mud¡¦ (30%) at high tidal level. At mid tidal level, higher percentages of
¡¥Soft mud¡¦ (60%) and ¡¥Sands¡¦ (40%) were recorded. At low tideal level, the main
substratum type was ¡¥Gravels and Boulders¡¦ (90%).
¡P
In ST, ¡¥Gravels and Boulders¡¦ was the main substratum type (100%) at high
tidal level. At mid tidal level, there were even distribution of ¡¥Gravels and
Boulders¡¦ (50%) and ¡¥Sands¡¦ (50%). At low tidal level, ¡¥Sands¡¦ was the main
substratum type (80%).
6.5.41 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.
6.5.42 Table 3.4 of Appendix I lists the total
abundance, density and number of taxon of every phylum in
this survey. A total of 14429 individuals
were recorded. Mollusca was clearly the
most abundant phylum (total abundance 14217 ind., density 474 ind. m-2, relative abundance 98.5 %). The second and third abundant phya were Arthropoda (114 ind., 4 ind. m-2, 0.8 %) and Annelida (70 ind., 2 ind. m-2, 0.5 %) respectively. Relatively other phyla were very low in abundances (density £1 ind. m-2, relative abundance £0.1 %). Moreover, the most diverse phylum was Mollusca (33 taxa)
followed by Arthropoda (10
taxa) and Annelida (9 taxa). There was 1-2 taxa recorded only for other phyla.
6.5.43
The taxonomic resolution and complete list of recorded fauna are shown
in Annexes IV and V of Appendix I respectively. As reported in Jun. 2018, taxonomic revision of three potamidid
snail species was conducted according to the latest identification key
published by Agriculture, Fisheries and Conservation Department (details see
AFCD, 2018), the species names of following gastropod species were revised:
¡P
Cerithidea cingulata was revised as Pirenella
asiatica
¡P
Cerithidea djadjariensis was revised as Pirenella
incisa
¡P
Cerithidea rhizophorarum was revised as Cerithidea
moerchii
Morover, taxonomic revision was conducted on another
snail species while the specie name was revised.:
¡P
Batillaria bornii was revised as Clypeomorus bifasciata
6.5.44 Table 3.5 of Appendix I shows
the number of individual, relative abundance and density of each phylum in every sampling zone. The total abundance (2195-4738
ind.) varied among the four sampling zones while the phyla distributions were similar. In general, Mollusca was the
most dominant phylum (no. of individuals: 2152-4690
ind.; relative abundance 97.9-99.1 %; density 287-625 ind. m-2). Other phyla were much lower in number of individuals. Arthropoda (16-49
ind.; 0.6-1.1 %; 2-7 ind. m-2) and Annelida (2-36 ind.; 0.1-0.9 %; 0-5 ind. m-2)
were common phyla relatively. Other
phyla were very low in abundance in all sampling zones.
Dominant species in every sampling zone
6.5.45
Table 3.6 of Appendix I lists the abundant species (relative abundance >10 %) in every sampling zone. In the present survey, most of the listed
abundant species were of low to moderate densities (50-250 ind. m-2).
Few listed species of high or very high density (> 250 ind. m-2)
were regarded as dominant species. Other listed species of lower density (<
50 ind. m-2) were regarded as common species.
6.5.46
In TC1, the substratum was mainly ¡¥Gravels
and Boulders¡¦ at high and mid tidal levels. The high tidal level was clearly
dominated by gastropod Batillaria multiformis (514 ind. m-2,
relative abundance 68 %) at very high density followed by gastropod Pirenella
incisa (98 ind. m-2, 13 %). At mid tidal level,
gastropod Batillaria multiformis (184 ind. m-2, 33 %)
and Monodonta labio (156 ind. m-2, 28 %) were
abundant at moderate densities. Rock oyster Saccostrea cucullata (86
ind. m-2, 16 %, attached on boulders) was also abundant at
low-moderate density. At low tidal level (main substratum types ¡¥Gravels
and Boulders¡¦ or ¡¥Soft
mud¡¦), rock oyster Saccostrea cucullata (207 ind. m-2, 35 %)
was more abundant at moderate density. Other gastropods Pirenella incisa (103
ind. m-2, 17 %), Batillaria zonalis (75 ind. m-2, 13
%) and Lunella coronata (61 ind. m-2, 10 %) were
found at low-moderate densities.
6.5.47
In TC2, the
substratum types were mainly 'Sands' at high
tidal level. Gastropods Pirenella incisa (100 ind. m-2, 28 %), Pirenella asiatica (63 ind. m-2, 17 %) and rock oyster Saccostrea cucullata
(68 ind., 19 %, attached on boulders) were abundant at low-moderate densities.
Other gastropods Batillaria zonalis (45 ind. m-2, 13 %)
and Batillaria multiformis (40 ind. m-2, 11 %) were also
common. At mid tidal level (main substratum type ¡¥Soft mud¡¦), rock oyster Saccostrea
cucullata (124 ind. m-2, 36 %) was abundant at moderate density
followed by gastropods Pirenella incisa (63 ind. m-2, 18 %)
and Batillaria zonalis (49 ind. m-2, 14 %). At low tidal
level (main substratum type ¡¥Soft mud¡¦), gastropod Batillaria zonalis (70 ind. m-2, 41 %)
was abundant at low-moderate desnity followed by common rocky oyster Saccostrea
cucullata (31 ind. m-2, 18 %) and gastropod Pirenella
asiatica (19 ind. m-2, 11 %).
6.5.48
In TC3, the substratum types were either ¡¥Sands¡¦ or ¡¥Soft mud¡¦ at high and
mid tidal levels. Gastropod Pirenella incisa (233-365 ind. m-2, 47-64 %) was dominant followed by gastropods
Pirenella asiatica (67-126 ind.
m-2, 12-25 %) and Batillaria multiformis (80-82 ind. m-2,
14-16 %) at low-moderate densities. At low tidal level (major
substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata (266 ind. m-2, 38 %,
attached on boulders) and gastropod Monodonta labio (220 ind. m-2, 31 %) were abundant
at moderate densities, followed by gastropod Lunella
coronata (77 ind. m-2, 11 %).
6.5.49
In ST, the major substratum type was ¡¥Gravels
and Boulders¡¦ at high tidal level. There were few abundant gastropod species at
low-moderate densities including Batillaria multiformis (123 ind. m-2, 26 %), Monodonta labio (97 ind. m-2, 20 %), Lunella
coronata (52 ind. m-2, 11 %) and Clypeomorus bifasciata (50 ind. m-2,
10 %). At mid and low tidal levels (main substratum types ¡¥Gravels and Boulders¡¦ and 'Sands'),
rock oyster Saccostrea
cucullata (52-143 ind. m-2, 22-28 %, attached on boulders) was more abundant
at low-moderate densities. Other abundant gastropods Pirenella incisa (44-82
ind. m-2, 16-19 %), Monodonta labio (36-77 ind. m-2, 15-16 %) and Lunella
coronata (25-76 ind. m-2, 11-15 %) were at low-moderate
densities. Besides, gastropod Pirenella asiatica (74 ind. m-2,
14 %) was also abundant at mid tidal level.
6.5.50 In general, there was no consistent zonation pattern of
species distribution across all sampling zones and tidal levels. The
species distribution was determined by the type of substratum primarily.
In general, gastropods Pirenella incisa (total number of individuals: 2921 ind., relative abundance 20.2 %), Batillaria multiformis (2628
ind., 18.2 %), Pirenella asiatica (1421
ind., 9.8 %) and Batillaria zonalis (769 ind.,
5.3 %) were
the most commonly occurring species on sandy and soft mud substrata. Rock oyster Saccostrea
cucullata (2635 ind., 18.3 %), gastropods Monodonta
labio (1806 ind., 12.5 %) and Lunella coronata (881
ind., 6.1 %) were the
commonly occurring species inhabiting gravel and boulders substratum.
Biodiversity and abundance of soft shore communities
6.5.51 Table 3.7 of Appendix I shows the mean values of species number,
density, biodiversity index H¡¦ and species evenness J of soft shore communities at every tidal level and in every sampling zone. As mentioned above, the
differences among sampling zones and tidal levels were determined by the major type of substratum primarily.
6.5.52 Among the sampling zones, the mean
species number was similar (6-9 spp. 0.25 m-2) among the four
sampling zones. The mean densities of TC1 and TC3 (591-632 ind. m-2)
were higher than ST (409 ind. m-2) followed by TC2 (293 ind. m-2).
Overall, ST was relatively higher in H'
(1.6) and J (0.8) due to higher
species number and even taxa distribution. In TC1 and TC3, higher densities
were mainly accounted by 1-2 abundant gastropods. It
resulted in lower H¡¦ (1.2-1.3) and J (0.6-0.7). In TC2, lower species
number and density also resulted in lower H'
(1.3) and J (0.7).
6.5.53 Among the tidal levels, there were
slightly increasing trends of mean species number, H' and J from high to low
tidal level in TC1 and TC3 but vice versa in TC2 and ST. A general decreasing
trend of mean density was observed from high to low tidal level in TC1, TC2 and
ST. As mentioned, the spatial differences of these biological parameters were
highly related to substratum types.
6.5.54 Figures 3.14 to 3.17 of Appendix I show the temporal changes of mean species number, mean density, H¡¦ and J at every tidal level and in every sampling
zone along the sampling months. In general, all the biological parameters fluctuated
seasonally throughout the monitoring period. Lower mean species number and
density were recorded in dry season (Dec.) but the mean H' and J fluctuated
within a limited range.
6.5.55 From Jun. to Dec. 2017, there
were steady decreasing trends of mean species number and density in TC2, TC3
and ST regardless of tidal levels. It might be an unfavourable change
reflecting environmental stresses. The heat stress and serial cyclone hit were
believed the causes during the wet season of 2017. From Mar. to Oct. 2018,
increases of mean species number and density were observed in all sampling
zones. It indicated the recovery of intertidal community.
Impact
of the HKLR project
6.6.1 AFCD, 2018. Potamidid
Snails in Hong Kong Mangrove. Agriculture, Fisheries and Conservation
Department Newsletter - Hong Kong Biodiversity Issue #25, 2-11
6.6.2 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.
6.6.3 Dai,
A.Y., Yang, S.L., 1991. Crabs of the China Seas. China Ocean Press. Beijing.
6.6.4 Dong,
Y.M., 1991. Fauna of ZheJiang Crustacea. Zhejiang Science and Technology
Publishing House. ZheJiang.
6.6.5 EPD,
1997. Technical Memorandum on Environmental Impact Assessment Process (1st
edition). Environmental Protection Department, HKSAR Government.
6.6.6 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..
6.6.7 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.
6.6.8 Li,
H.Y., 2008. The Conservation of Horseshoe Crabs in Hong Kong. MPhil Thesis,
City University of Hong Kong, pp 277.
6.6.9 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.
6.6.10 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.
6.6.11 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.
6.6.12 Pielou,
E.C., 1966. Shannon¡¦s formula as a measure of species diversity: its use and
misuse. American Naturalist 100, 463-465.
6.6.13 Qi,
Z.Y., 2004. Seashells of China. China Ocean Press. Beijing, China.
6.6.14 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, p9-10.
6.6.15 Shannon,
C.E., Weaver, W., 1963. The Mathematical Theory of Communication. Urbana:
University of Illinois Press, USA.
6.6.16 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.
6.6.17 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.
6.6.18 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.
6.6.19 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, four site inspections
were carried out on 5, 12, 19, and 28
December 2018.
7.1.2 A summary of observations
found during the site inspections and the follow up actions taken by the Contractor are described in Table 7.1.
Table 7.1 Summary
of Environmental Site Inspections
Date of Audit
|
Observations
|
Actions Taken by
Contractor / Recommendation
|
Date of Observations
Closed
|
30 Nov 2018
|
1. Stagnant water was observed at N4.
2. Waste was observed at N4
3.
Dry
stockpile was observed at N4.
4.
Waste
was observed at LCSD.
|
1. The stagnant water was removed from N4.
2. The waste was removed from N4.
3. The dry stockpile was removed from N4.
4. The waste was removed from LCSD.
|
5 Dec 2018
|
5 Dec 2018
|
1.
Waste
was observed at LCSD Depot.
2.
Waste was
accumulated in a skip at N4.
|
1. The waste was
removed from LCSD Depot.
2. The waste was removed from the skip at N4.
|
12 Dec 2018
|
12 Dec 218
|
1.
Waste
was observed at LCSD Depot.
2.
Stagnant water was
observed at N4.
|
1. The waste was
removed from LCSD Depot.
2. The
stagnant water was removed at N4.
|
19 Dec 2018
|
19 Dec 2018
|
1.
Waste
was observed at LCSD Depot.
2.
Stockpile
of dusty material was observed dry at N4.
3.
Waste was
accumulated in a skip at N4.
|
1.
The waste was removed from LCSD Depot.
2.
The
dry stockpile of dusty material was removed from N4.
3.
The waste was removed from the skip at N4.
|
28 Dec 2018
|
28 Dec 2018
|
1.
Waste
was observed at LCSD Depot.
2.
Waste
was observed at N4 .
3.
Containers
of liquid chemicals were observed without drip trays underneath at N4.
4.
Stockpiles
of material were placed around a Tree at N4.
5.
Wheel
washing facilities were missing at N4.
|
The Contractor was recommended to:
1.
remove
the waste at LCSD Depot
2.
remove
the waste at N4.
3.
provide
drip trays for the chemical containers at N4.
4.
remove
the stockpiles of material near the tree at N4.
5.
provide
wheel washing facilities at N4.
|
Follow-up actions for the observations
issued for the last weekly site inspection of the reporting month will be inspected during the next
site inspection.
|
7.1.3 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 inspection.
7.2
Advice on the
Solid and Liquid Waste Management Status
7.2.1 The Contractor
registered as a chemical waste producer for the Contract. 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
Implementation Status of Environmental
Mitigation Measures
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 For air quality, no Action and Limit
Level exceedances of 1-hr TSP and 24-hr TSP 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 station during the
reporting month.
7.5.3 For marine
water quality monitoring, no Action Level and Limit Level exceedances of
dissolved oxygen level and turbidity level were recorded during the reporting
month. During the reporting month, two Action
Level exceedance of suspended solids level was recorded. No Limit Level
exceedances of suspended solids level were recorded.
7.6
Summary of
Complaints, Notification of Summons and Successful Prosecution
7.6.1
There was one complaint received in
relation to the environmental impacts during the reporting month. Complaint investigation
is being undertaken and will be reported in next reporting month. A summary of
environmental complaint during the reporting month is presented in Table 7.2.
Table 7.2 A Summary of Environmental
Complaint during the Reporting Month
Environmental Complaint No.
|
Date
of Complaint Received
|
Description
of Environmental Complaint
|
Complaint No
COM-2018-158
|
SOR referred the email
from HyD to Contractor, ET and IEC/ENPO on 24 December 2018
|
Other: Construction work on Sunday Morning
|
7.6.2
The details of cumulative statistics of Environmental Complaints
are provided in Appendix K.
7.6.3
No notification of summons and prosecution
was received during the reporting period. Statistics on notifications of
summons and successful prosecutions are summarized in Appendix N.
8.1.1 As informed by the Contractor, the major
construction activities for January 2019 are summarized in Table 7.1.
Table 7.1 Construction
Activities for January 2019
Site Area
|
Description of
Activities
|
Portion X
|
Dismantling/
trimming of Temporary 40mm Stone Platform for Construction of Seawall
|
Portion X
|
Construction of Seawall
|
Portion X
|
Loading and Unloading of Filling Materials
|
Portion X
|
Backfilling at Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Airport Road
|
Works for Diversion of
Airport Road
|
Airport Road / Airport Express Line/ East Coast Road
|
Establishment of Site Access
|
Portion X
|
Finishing works for Highway Operation and Maintenance Area Building
|
West Portal
|
Finishing Works for Scenic Hill Tunnel West Portal Ventilation Building
|
8.1.2 The tentative schedule for environmental
monitoring in January 2019 is provided in Appendix D.
9.1.1
The construction phase and EM&A programme of the
Contract commenced on 17 October 2012. This is the seventy-fifth 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 31 December 2018.
Air Quality
9.1.2 For air quality, No Action Level and
Limit Level exceedance of 1-hr TSP and 24-hr TSP 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
station during the reporting month.
Water Quality
9.1.4
For marine water quality monitoring, no Action
Level and Limit Level exceedances of dissolved oxygen level and turbidity level
were recorded during the reporting month. During the reporting month, two Action
Level exceedance of suspended solids level was recorded. No Limit Level
exceedances of suspended solids level were recorded.
Dolphin
9.1.5 During the December¡¦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 (December 2018 ¡V February 2019) 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.
Environmental Site Inspection and
Audit
9.1.9
Environmental site inspections were carried out on 5, 12, 19, and 28 December 2018. Recommendations on remedial actions were given to the
Contractors for the deficiencies identified during the site inspections.
9.1.10
There was one complaint
received in relation to the environmental impact during the reporting period. Complaint investigation is being
undertaken and will be reported in next reporting month.
9.1.11
No
notification of summons and prosecution was received during the reporting
period.