Contract No. HY/2011/03
Hong
Kong-Zhuhai-Macao Bridge Hong Kong Link Road
Section between Scenic
Hill and Hong Kong Boundary Crossing Facilities
Quarterly EM&A Report
No. 28 (June 2019 to August 2019)
10 December 2019
Revision 1
Main Contractor Designer
Executive Summary
The
Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong Kong Link Road (HKLR) serves to
connect the HZMB Main Bridge at the Hong Kong Special Administrative Region
(HKSAR) Boundary and the HZMB Hong Kong Boundary Crossing Facilities (HKBCF)
located at the north eastern waters of the Hong Kong International Airport
(HKIA).
The
HKLR project has been separated into two contracts. They are Contract No.
HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between
Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter referred to
as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao Bridge Hong
Kong Link Road-Section between HKSAR Boundary and Scenic Hill.
China
State Construction Engineering (Hong Kong) Ltd. was awarded by Highways
Department as the Contractor to undertake the construction works of Contract
No. HY/2011/03. The main works of the Contract include land tunnel at Scenic
Hill, tunnel underneath Airport Road and Airport Express Line, reclamation and
tunnel to the east coast of the Airport Island, at-grade road connecting to the
HKBCF and highway works of the HKBCF within the Airport Island and in the
vicinity of the HKLR reclamation.
The Contract is part of the HKLR Project and HKBCF Project, these
projects are considered to be ¡§Designated Projects¡¨, under Schedule 2 of the
Environmental Impact Assessment (EIA) Ordinance (Cap 499) and EIA Reports
(Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for the
Project. The current Environmental
Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/K for HKBCF were issued on 22
December 2014 and 11 April 2016, respectively. These documents are available
through the EIA Ordinance Register. The construction phase of Contract was commenced on 17 October 2012.
BMT 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 twenty-eighth Quarterly EM&A report for the Contract which summarizes
the monitoring results and audit findings of the EM&A programme during the
reporting period from 1 June 2019 to 31 August 2019.
Environmental
Monitoring and Audit Progress
The EM&A programme were undertaken in
accordance with the Updated EM&A Manual for HKLR (Version 1.0). A summary of the monitoring activities
during this reporting period is presented as below:
Monitoring Activity
|
Monitoring
Date
|
Jun 2019
|
Jul 2019
|
Aug 2019
|
Air
Quality
|
1-hr
TSP
|
3, 6, 12, 18, 24 and 28
|
4, 10, 16, 22 and 26
|
1, 7, 13, 19, 23 and 29
|
24-hr
TSP
|
5, 11, 17, 21 and 27
|
3, 9, 15, 19, 25 and 31
|
AMS5:
6, 12, 16, 26 and 28
AMS6: 6, 12, 16, 22
and 28
|
Noise
|
3, 12, 18 and 28
|
4, 10, 16, 22 and 30
|
7, 13, 19 and 29
|
Water Quality
|
3, 5, 7, 10, 12, 14, 17, 19, 21, 24, 26 and 28
|
1, 3, 5, 8, 10, 12, 15, 17, 19, 22, 24, 26 and 29
|
2, 5, 7, 9, 12, 14, 16, 19, 21, 23, 26, 28 and 30
|
Chinese
White Dolphin
|
3,
6, 10 and 13
|
16,
18, 22 and 24
|
13, 14, 20, 26 and 29
|
Mudflat Monitoring (Ecology)
|
4, 5, 17 and 18
|
-
|
-
|
Mudflat Monitoring (Sedimentation rate)
|
20
|
-
|
-
|
Site Inspection
|
5,
12, 19 and 28
|
3,
10, 17 and 26
|
1,
7, 14, 21 and 30
|
Due to unfavourable weather condition (Raining & Thunderstorm),
sedimentation rate monitoring on 17 June 2019 was rescheduled to 20 June 2019.
As Strong Wind Signal, No. 3 was hoisted by Hong Kong Observatory on 31
July 2019. The water quality monitoring for mid-flood and mid-ebb tide on 31
July 2019 was cancelled due to safety reasons and no substitute monitoring will
be conducted.
Due to weather condition, the noise monitoring at NMS5 was rescheduled
from 24 June 2019 to 28 June 2019; and from1 August 2019 to 30 July 2019.
Due to unavailability of staff, the dolphin monitoring was rescheduled
from 12 June 2019 to 13 June 2019.
Due to engine problem of the survey boat, the dolphin monitoring on 6
August 2019 was rescheduled to 13 August 2019.
Due to boat unavailability, the dolphin monitoring was rescheduled from
29 July 2019 to 16 July 2019; and from 21 and 28 August 2019 to 20 and 26
August 2019 respectively.
As the rain was unexpectedly heavy on 26 August 2019, the 2nd
dolphin monitoring cannot be completed on 26 August 2019. As such, the dolphin
monitoring was rescheduled and completed on 29 August 2019.
Due to malfunction of the high volume sampler (HVS), monitoring time for
24-hr TSP monitoring on 22 August 2019 at AMS5 (Ma Wan Chung Village) was less
than 24 hours. The 24-hr TSP monitoring on 22 August 2019 at AMS5 was
rescheduled to 26 August 2019.
Breaches of Action and Limit Levels
A
summary of environmental exceedances for this reporting period is as follows:
Environmental Monitoring
|
Parameters
|
Action Level (AL)
|
Limit Level (LL)
|
Air Quality
|
1-hr
TSP
|
0
|
0
|
24-hr
TSP
|
0
|
0
|
Noise
|
Leq (30 min)
|
0
|
0
|
Water Quality
|
Suspended
solids level (SS)
|
0
|
0
|
Turbidity
level
|
0
|
0
|
Dissolved
oxygen level (DO)
|
8
|
4
|
Dolphin Monitoring
|
Quarterly
Analysis (Jun 2019 to Aug 2019)
|
0
|
1
|
All
investigation reports for exceedances of the Contract have been submitted to
ENPO/IEC for comments and/or follow up to identify whether the exceedances
occurred related to other HZMB contracts.
Implementation of Mitigation Measures
Site
inspections were carried out to monitor the implementation of proper environmental
pollution control and mitigation measures for the Project. Potential
environmental impacts due to the construction activities were monitored and
reviewed.
Complaint Log
There
was no complaint received in relation to the environmental impacts during this
reporting period.
Notifications of Summons
and Prosecutions
There
were no notifications of summons or prosecutions received during this reporting
period.
Reporting Changes
This
report has been developed in compliance with the reporting requirements for the
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.
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.
The works area WA5
was handed over to other party on 22 June 2013.
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.
Original WQM stations
IS8 and SR4(N) are located within the active work area of TCNTE project and the
access to the WQM stations IS8 (Coordinate: E814251, N818412) and SR4(N) (Coordinate:
E814705, N817859) are blocked by the silt curtains of the Tung Chung New Town
Extension (TCNTE) project. Alternative monitoring stations IS8(N) (Coordinate:
E814413, N818570) and SR4(N2) (Coordinate: E814688, N817996) are proposed to
replace the original monitoring stations IS8 and SR4(N). Proposal for
permanently relocating the aforementioned stations was approved by EPD on 20
August 2019. The water quality monitoring has been conducted at
stations IS8(N) and SR4(N2) on 21 August 2019.
1.1.2
The HKLR project has been
separated into two contracts. They are Contract
No. HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section
between Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter
referred to as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao
Bridge Hong Kong Link Road-Section between HKSAR Boundary and Scenic Hill.
1.1.3
China State Construction
Engineering (Hong Kong) Ltd. was awarded by Highways Department (HyD) as the Contractor to undertake the construction works
of Contract No. HY/2011/03. The Contract is part of the HKLR
Project and HKBCF Project, these projects are considered to be ¡§Designated
Projects¡¨, under Schedule 2 of the Environmental Impact Assessment (EIA)
Ordinance (Cap 499) and EIA Reports (Register No. AEIAR-144/2009 and
AEIAR-145/2009) were prepared for the Project. The current Environmental Permit (EP) EP-352/2009/D
for HKLR and EP-353/2009/K for HKBCF were issued on 22 December 2014 and 11
April 2016, respectively. These documents are available through the EIA
Ordinance Register. The construction phase of Contract was commenced on 17 October 2012. The works area WA7 was handed
over to other party on 31 January 2018. Figure 1.1 shows
the project site boundary.
1.1.4
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 provided in Appendix A.
1.1.5
This is the twenty-eighth Quarterly Environmental Monitoring and Audit (EM&A) report for the
Contract which summarizes the monitoring results and audit findings of the
EM&A programme during the reporting period from 1
June 2019 to 31 August 2019.
1.2.1 The project organization structure and lines of
communication with respect to the on-site environmental management structure
with the key personnel contact names and numbers are shown in Appendix A.
1.3
Construction Programme
1.3.1 A
copy of the Contractor¡¦s construction programme is
provided in Appendix B.
1.4
Construction
Works Undertaken During the Reporting Period
1.4.1 A
summary of the construction activities undertaken during this reporting period
is shown in Table
1.1. The Works
areas of the Contract are showed in Appendix C.
Table 1.1 Construction
Activities during Reporting Period
Description of Activities
|
Site Area
|
Dismantling/trimming of temporary 40mm
stone platform for construction of seawall
|
Portion X
|
Construction of seawall
|
Portion X
|
Loading and unloading of fill materials
|
Portion X
|
Landscaping works
|
Portion X and Airport Road
|
Works
for diversion
|
Airport Road
|
Establishment
of Site Access
|
Airport Road / Airport Express Line/ East
Coast Road
|
E&M
works
|
Airport 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
Summary of EM&A Requirements
2.1.1
The EM&A programme requires environmental
monitoring of air quality, noise, water quality, dolphin monitoring and mudflat
monitoring as specified in the approved EM&A Manual.
2.1.2 A summary of Impact
EM&A requirements is presented in Table
2.1. The
locations of air quality, noise and water quality monitoring stations are shown
as in Figure 2.1. The transect line
layout in Northwest and Northeast Lantau Survey Areas is presented in Figure
2.2.
Table 2.1 Summary
of Impact EM&A Requirements
Environmental
Monitoring
|
Description
|
Monitoring
Station
|
Frequencies
|
Remarks
|
Air Quality
|
1-hr TSP
|
AMS 5 & AMS
6
|
At least 3 times every 6 days
|
While the
highest dust impact was expected.
|
24-hr TSP
|
At least once every 6 days
|
--
|
Noise
|
Leq (30mins),
L10 (30mins) and
L90 (30mins)
|
NMS 5
|
At least once per week
|
Daytime on normal weekdays
(0700-1900 hrs).
|
Water Quality
|
¡P Depth
¡P Temperature
¡P Salinity
¡P Dissolved
Oxygen (DO)
¡P Suspended
Solids (SS)
¡P DO
Saturation
¡P Turbidity
¡P pH
|
¡P Impact
Stations:
IS5, IS(Mf)6, IS7, IS8/IS8(N), IS(Mf)9 & IS10(N),
¡P Control/Far
Field Stations:
CS2(A) & CS(Mf)5,
¡P Sensitive
Receiver Stations:
SR3(N), SR4(N)/ SR4(N2), SR5(N), SR10A(N) & SR10B(N2)
|
Three times per week
during mid-ebb and mid-flood tides (within ¡Ó 1.75 hour of the predicted time)
|
3
(1 m below water surface,
mid-depth and 1 m above sea bed, except where the water depth is less than 6
m, in which case the mid-depth station may be omitted. Should the water depth be less than 3
m, only the mid-depth station will be monitored).
|
Dolphin
|
Line-transect Methods
|
Northeast Lantau survey
area and Northwest Lantau survey area
|
Twice
per month
|
--
|
Mudflat
|
Horseshoe crabs, seagrass beds, intertidal soft shore communities,
sedimentation rates and water quality
|
San Tau and Tung Chung Bay
|
Once every 3 months
|
--
|
Remark: 1) 1) Original WQM stations IS8 and
SR4(N) are located within the active work area of TCNTE project and the access
to the WQM stations IS8 (Coordinate: E814251, N818412) and SR4(N) (Coordinate:
E814705, N817859) are blocked by the silt curtains of the Tung Chung New Town
Extension (TCNTE) project. Alternative monitoring stations IS8(N) (Coordinate:
E814413, N818570) and SR4(N2) (Coordinate: E814688, N817996) are proposed to
replace the original monitoring stations IS8 and SR4(N). Proposal for
permanently relocating the aforementioned stations was approved by EPD on 20
August 2019. The water quality monitoring has been conducted at stations IS8(N)
and SR4(N2) on 21 August 2019.
2.2
Action and
Limit Levels
2.2.1
Table 2.2 presents the Action
and Limit Levels for the 1-hour TSP, 24-hour TSP and noise level.
Table 2.2 Action and
Limit Levels for 1-hour TSP, 24-hour
TSP and Noise
Environmental Monitoring
|
Parameters
|
Monitoring Station
|
Action Level
|
Limit Level
|
Air Quality
|
1-hr
TSP
|
AMS
5
|
352 µg/m3
|
500 µg/m3
|
AMS
6
|
360 µg/m3
|
24-hr
TSP
|
AMS
5
|
164 µg/m3
|
260 µg/m3
|
AMS
6
|
173 µg/m3
|
Noise
|
Leq (30 min)
|
NMS 5
|
When
one documented complaint is received
|
75
dB(A)
|
2.2.2 The Action and Limit Levels for water quality monitoring are given as in
Table 2.3.
Table 2.3 Action
and Limit Levels for Water Quality
Parameter
(unit)
|
Water Depth
|
Action
Level
|
Limit Level
|
Dissolved Oxygen (mg/L)
|
Surface and Middle
|
5.0
|
4.2 except 5 for Fish
Culture Zone
|
Bottom
|
4.7
|
3.6
|
Turbidity (NTU)
|
Depth average
|
27.5 or 120% of upstream
control station¡¦s turbidity at the same tide of the same day;
The action level has been
amended to ¡§27.5 and 120% of upstream control station¡¦s turbidity at the same
tide of the same day¡¨ since 25 March 2013.
|
47.0 or 130% of turbidity
at the upstream control station at the same tide of same day;
The limit level has been
amended to ¡§47.0 and 130% of turbidity at the upstream control station at the
same tide of same day¡¨ since 25 March 2013.
|
Suspended Solid (SS)
(mg/L)
|
Depth average
|
23.5 or 120% of upstream
control station¡¦s SS at the same tide of the same day;
The action level has been
amended to ¡§23.5 and 120% of upstream control station¡¦s SS at the same tide of
the same day¡¨ since 25 March 2013.
|
34.4 or 130% of SS at the
upstream control station at the same tide of same day and 10mg/L for Water
Services Department Seawater Intakes;
The limit level has been
amended to ¡§34.4 and 130% of SS at the upstream control station at the same
tide of same day and 10mg/L for Water Services Department Seawater Intakes¡¨
since 25 March 2013
|
Notes:
(1) Depth-averaged
is calculated by taking the arithmetic means of reading of all three depths.
(2) For DO,
non-compliance of the water quality limit occurs when monitoring result is
lower that the limit.
(3) For SS &
turbidity non-compliance of the water quality limits occur when monitoring
result is higher than the limits.
(4) The change to
the Action and limit Levels for Water Quality Monitoring for the EM&A works
was approved by EPD on 25 March 2013. Therefore, the amended Action and Limit
Levels are applied for the water monitoring results obtained on and after 25
March 2013.
2.2.3
The Action and Limit Levels
for dolphin monitoring are shown in Tables
2.4 and 2.5.
Table 2.4 Action
and Limit Level for Dolphin Impact Monitoring
|
North Lantau
Social Cluster
|
NEL
|
NWL
|
Action Level
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
Limit Level
|
STG < 40% of baseline
&
ANI < 40% of baseline
|
Remarks:
(1)
STG means quarterly average encounter rate of
number of dolphin sightings.
(2)
ANI means quarterly average encounter rate of
total number of dolphins.
(3)
For North Lantau Social Cluster, AL will be
triggered if either NEL or NWL fall below the criteria; LL will be triggered if
both NEL and NWL fall below the criteria.
Table 2.5 Derived
Value of Action Level (AL) and Limit Level (LL)
|
North Lantau
Social Cluster
|
NEL
|
NWL
|
Action Level
|
STG < 4.2 & ANI
< 15.5
|
STG < 6.9 & ANI
< 31.3
|
Limit Level
|
(STG < 2.4 & ANI
< 8.9) and (STG < 3.9 & ANI < 17.9)
|
Remarks:
(1)
STG means quarterly average encounter rate of
number of dolphin sightings.
(2)
ANI means quarterly average encounter rate of
total number of dolphins.
(3)
For North Lantau Social Cluster, AL will be
triggered if either NEL or NWL fall below the criteria; LL will be triggered if
both NEL and NWL fall below the criteria.
2.3.1 The Event Actions Plans for air quality, noise, water quality and
dolphin monitoring are annexed in Appendix D.
2.4.1 Environmental mitigation measures for the
contract were recommended in the approved EIA Report. Appendix E lists the recommended mitigation measures and the implementation
status.
3
Environmental Monitoring and Audit
3.1
Implementation of Environmental Measures
3.1.1
In response to the environmental site audit findings,
the Contractor have rectified most of the observations as identified in environmental
site inspections undertaken during the reporting period. Details of site audit
findings and the corrective actions during the reporting period are presented
in Appendix F.
3.1.2 Summary of environmental site inspections of landscape works for the
Contract works area are presented in Appendix F. The landscape work for the Contract
was conducted during the reporting period. The implementation of mitigation
measures for landscape and visual resources recommended in the EIA Report were
monitored during the reporting period. Landscape and visual mitigation measures
in accordance with the EP, EIA and EM&A Manual were implemented by the
Contractor.
3.1.3
A summary of the Implementation Schedule of
Environmental Mitigation Measures (EMIS) is presented in Appendix E. Most of the
necessary mitigation measures were implemented properly.
3.1.4
Regular marine travel route for
marine vessels were implemented properly in accordance to the submitted plan
and relevant records were kept properly.
3.1.5
Dolphin Watching Plan was
implemented during the reporting period. No dolphins inside the silt curtain were observed. The relevant
records were kept properly.
3.2.1
The monitoring results for 1-hour TSP and 24-hour TSP
are summarized in Tables 3.1 and 3.2 respectively.
Detailed impact air quality monitoring results and relevant graphical
plots are presented in Appendix G.
Table 3.1 Summary
of 1-hour TSP Monitoring Results Obtained During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
Jun 2019
|
AMS5
|
35
|
29 ¡V 42
|
352
|
500
|
AMS6
|
34
|
30 ¡V 41
|
360
|
Jul 2019
|
AMS5
|
43
|
34 ¡V 61
|
352
|
AMS6
|
38
|
31 ¡V 52
|
360
|
Aug 2019
|
AMS5
|
44
|
11-199
|
352
|
AMS6
|
48
|
15-103
|
360
|
Table 3.2 Summary
of 24-hour TSP Monitoring Results Obtained During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
Jun 2019
|
AMS5
|
22
|
13 ¡V 29
|
164
|
260
|
AMS6
|
19
|
10 ¡V 25
|
173
|
Jul 2019
|
AMS5
|
32
|
20 ¡V 42
|
164
|
AMS6
|
34
|
17 ¡V 44
|
173
|
Aug 2019
|
AMS5
|
33
|
27-50
|
164
|
AMS6
|
40
|
25-75
|
173
|
3.2.2
No Action and Limit Level exceedances
of 1-hr TSP and 24-hr TSP were recorded at AMS5 and AMS6 during the reporting period.
3.3
Noise
Monitoring Results
3.3.1
The monitoring results for construction noise are
summarized in Table 3.3 and the monitoring
results and relevant graphical plots for this reporting period are provided in Appendix H.
Table 3.3 Summary of Construction Noise Monitoring
Results Obtained During the Reporting Period
Reporting period
|
Monitoring Station
|
Average Leq (30 mins), dB(A)*
|
Range of Leq (30 mins), dB(A)*
|
Action Level
|
Limit Level Leq (30 mins), dB(A)
|
Jun 2019
|
NMS5
|
58
|
57 ¡V 58
|
When one documented complaint is received
|
75
|
Jul 2019
|
58
|
56 ¡V 60
|
Aug 2019
|
59
|
56 ¡V 65
|
3.3.2 No Action/Limit Level exceedances for noise were recorded during
daytime on normal weekdays of the reporting period.
3.3.3
Major noise sources during the noise monitoring
included aircraft/helicopter noise and nearby construction activities by other
parties.
3.4.1 Impact water quality
monitoring was conducted at all designated monitoring stations during the reporting
period. Impact water quality monitoring results and relevant graphical plots
are provided in Appendix I.
3.4.2 No Action Level and Limit Level exceedances
of turbidity level and suspended solids level were recorded during the
reporting period. No
Action/Limit Level exceedances of dissolved oxygen were recorded at bottom
level during mid-ebb tide. No Limit Level exceedances of dissolved
oxygen were recorded at bottom level during mid-flood tide.
3.4.3 2 Action
Level exceedances of dissolved oxygen at stations IS10(N), SR5(N) and 2 Limit
Level exceedances of dissolved oxygen were recorded at SR10A(N), SR10B(N2) at surface and middle level during mid-ebb tide.
2 Action Level exceedances of dissolved oxygen at stations IS10(N), SR5(N) and
2 Limit Level exceedances of dissolved oxygen were recorded at SR10A(N), SR10B(N2) at surface and middle level during mid-flood
tide. 4 Action Level exceedances of dissolved oxygen were recorded at IS10(N),
SR5(N), SR10A(N) and SR10B(N2) at bottom level during mid-flood tide. The exceedances of suspended solids level recorded during
reporting period was considered to be attributed to other external factors such
as sea condition, rather than the contract works. The exceedances were
considered as non-contract related. Record of ¡§Notification of Environmental
Quality Limit Exceedances¡¨ is provided in Appendix M.
3.4.4
Water quality impact sources during the water quality
monitoring were the construction activities of the Contract, nearby
construction activities by other parties and nearby operating vessels by other
parties.
Data Analysis
3.5.1
Distribution
Analysis ¡V The line-transect survey data was integrated with the Geographic Information
System (GIS) in order to visualize and interpret different spatial and temporal
patterns of dolphin distribution using sighting positions. Location data of dolphin groups were
plotted on map layers of Hong Kong using a desktop GIS (ArcViewý 3.1)
to examine their distribution patterns in details. The dataset was also
stratified into different subsets to examine distribution patterns of dolphin
groups with different categories of group sizes, young calves and activities.
3.5.2 Encounter
rate analysis ¡V Encounter rates of Chinese white dolphins (number of on-effort
sightings per 100 km of survey effort, and total number of dolphins sighted
on-effort per 100 km of survey effort) were calculated in NEL and NWL survey
areas in relation to the amount of survey effort conducted during each month of
monitoring survey. Dolphin
encounter rates were calculated in two ways for comparisons with the HZMB
baseline monitoring results as well as to AFCD long-term marine mammal
monitoring results.
3.5.3 Firstly,
for the comparison with the HZMB baseline monitoring results, the encounter
rates were calculated using primary survey effort alone, and only data
collected under Beaufort 3 or below condition would be used for encounter rate
analysis. The average encounter
rate of sightings (STG) and average encounter rate of dolphins (ANI) were
deduced based on the encounter rates from six events during the present quarter
(i.e. six sets of line-transect surveys in North Lantau), which was also
compared with the one deduced from the six events during the baseline period
(i.e. six sets of line-transect surveys in North Lantau).
3.5.4 Secondly,
the encounter rates were calculated using both primary and secondary survey
effort collected under Beaufort 3 or below condition as in AFCD long-term
monitoring study. The encounter
rate of sightings and dolphins were deduced by dividing the total number of
on-effort sightings (STG) and total number of dolphins (ANI) by the amount of
survey effort for the present quarterly period.
3.5.5 Quantitative
grid analysis on habitat use ¡V To conduct quantitative grid analysis of habitat
use, positions of on-effort sightings of Chinese White Dolphins collected
during the quarterly impact phase monitoring period were plotted onto 1-km2
grids among NWL and NEL survey areas on GIS. Sighting densities (number of on-effort
sightings per km2) and dolphin densities (total number of dolphins
from on-effort sightings per km2) were then calculated for each 1 km
by 1 km grid with the aid of GIS.
Sighting density grids and dolphin density grids were then further
normalized with the amount of survey effort conducted within each grid. The total amount of survey effort spent
on each grid was calculated by examining the survey coverage on each
line-transect survey to determine how many times the grid was surveyed during
the study period. For example, when
the survey boat traversed through a specific grid 50 times, 50 units of survey
effort were counted for that grid.
With the amount of survey effort calculated for each grid, the sighting
density and dolphin density of each grid were then normalized (i.e. divided by
the unit of survey effort).
3.5.6
The newly-derived unit for sighting density was
termed SPSE, representing the number of on-effort sightings per 100 units of
survey effort. In addition, the
derived unit for actual dolphin density was termed DPSE, representing the
number of dolphins per 100 units of survey effort. Among the 1-km2 grids that
were partially covered by land, the percentage of sea area was calculated using
GIS tools, and their SPSE and DPSE values were adjusted accordingly. The following formulae were used to
estimate SPSE and DPSE in each 1-km2 grid within the study area:
SPSE = ((S / E) x 100) / SA%
DPSE = ((D / E) x 100) / SA%
where S
= total number of on-effort sightings
D = total number of dolphins from on-effort sightings
E = total number of units of survey effort
SA% = percentage of sea area
3.5.7
Behavioural analysis ¡V When dolphins were sighted
during vessel surveys, their behaviour was
observed. Different activities were
categorized (i.e. feeding, milling/resting, traveling, socializing) and
recorded on sighting datasheets.
This data was then input into a separate database with sighting
information, which can be used to determine the distribution of behavioural data with a desktop GIS. Distribution of sightings of dolphins
engaged in different activities and behaviours would
then be plotted on GIS and carefully examined to identify important areas for
different activities of the dolphins.
3.5.8
Ranging pattern analysis ¡V Location data of
individual dolphins that occurred during the 3-month baseline monitoring period
were obtained from the dolphin sighting database and photo-identification
catalogue. To deduce home ranges
for individual dolphins using the fixed kernel methods, the program Animal
Movement Analyst Extension, was loaded as an extension with ArcViewý
3.1 along with another extension Spatial Analyst 2.0. Using the fixed kernel method, the
program calculated kernel density estimates based on all sighting positions,
and provided an active interface to display kernel density plots. The kernel estimator then calculated and
displayed the overall ranging area at 95% UD level.
Summary of Survey Effort and Dolphin
Sightings
3.5.9 During the period of June to
August 2019, six sets of systematic line-transect vessel
surveys were conducted to cover all transect lines in NWL and NEL survey areas
twice per month.
3.5.10 From these surveys, a total of 785.23 km of
survey effort was collected, with 96.0% of the total survey effort being conducted under favourable weather conditions (i.e. Beaufort Sea State 3 or
below with good visibility). Among
the two areas, 287.33 km and 497.90 km of
survey effort were conducted in NEL and NWL survey areas respectively.
3.5.11 The
total survey effort conducted on primary lines was 577.21 km, while the effort on secondary lines was 208.02
km.
Survey effort conducted on both primary and secondary lines were
considered to be on-effort survey data. A summary table of the survey effort is
shown in Appendix J.
3.5.12 During the six sets of monitoring surveys conducted
between June 2019 and August 2019 only four groups of
eight Chinese White Dolphins were sighted, with the summary table of dolphin
sightings shown in Annex II of Appendix
J. Three of the four dolphin sightings were made during on-effort search, with two
of them being made on primary lines.
3.5.13 In addition, all dolphin groups were sighted in
NWL, and no dolphin was sighted at all in NEL. In fact, since
August 2014, only two sightings of two lone dolphins were made in NEL during
HKLR03 monitoring surveys.
Distribution
3.5.14 Distribution of dolphin sightings made during
HKLR03 monitoring surveys conducted from June to August 2019 is shown in
Figure 1 of Appendix
J. Two of the
four dolphin groups were sighted near Black Point, while another two was
sighted at the southwestern corner of NWL survey area, just to the south of the
HKLR09 alignment (Figure 1 of Appendix
J).
3.5.15 As consistently recorded in previous monitoring
quarters, the dolphins were completely absent from the central and eastern
portions of North Lantau waters (Figure 1 of Appendix J). Moreover, all dolphin sightings were
located very far away from the HKLR03 and HKBCF reclamation sites as well as
along the alignment of Tuen Mun ¡V Chek
Lap Kok Link (TMCLKL) (Figure 1 of Appendix J).
3.5.16 Sighting distribution of dolphins during the
present impact phase monitoring period (June-August 2019) was drastically
different from the one during the baseline monitoring period (Figure
1 of Appendix J. In the
present quarter, dolphins have disappeared from the NEL region, which was in
stark contrast to their frequent occurrences around the Brothers Islands, near
Shum Shui Kok and in the vicinity of HKBCF
reclamation site during the baseline period (Figure 1 of Appendix J).
The nearly complete abandonment of NEL region by the dolphins has been
consistently recorded in the past 25 quarters of HKLR03 monitoring, which has
resulted in zero to extremely low dolphin encounter rates in this area.
3.5.17 In NWL survey area, dolphin occurrence was also
drastically different between the baseline and impact phase periods. During the present impact monitoring
period, dolphins were rarely sighted there, and their distribution was
restricted to the northwestern and southwestern corners of the North Lantau
region, which was in stark contrast to their frequent occurrences throughout
the area during the baseline period (Figure 1 of Appendix J).
3.5.18 Another comparison in dolphin distribution was made
between the six quarterly periods of summer months in 2014-19. Among the six summer periods, dolphins
were regularly sighted in NWL waters in 2014, but such usage was progressively
reduced to very low levels in the five subsequent summer periods of 2015-19 (Figure 2 of Appendix J).
Encounter Rate
3.5.19 During
the present three-month study period, the encounter rates of Chinese White Dolphins
deduced from the survey effort and on-effort sighting data from the primary
transect lines under favourable conditions (Beaufort
3 or below) for each set of the surveys in NEL and NWL are shown in Table 3.4. The average encounter rates deduced from
the six sets of surveys were also compared with the ones deduced from the
baseline monitoring period (September ¡V November 2011) (Table 3.5).
3.5.20 To
facilitate the comparison with the AFCD long-term monitoring results, the
encounter rates were also calculated for the present quarter using both primary
and secondary survey effort. The
encounter rates of sightings (STG) and dolphins (ANI) in NWL were 0.64
sightings and 1.50 dolphins per 100 km of survey effort respectively, while the
encounter rates of sightings (STG) and dolphins (ANI) in NEL were both nil for
this quarter.
Table 3.4 Dolphin Encounter Rates
(Sightings Per 100 km of Survey Effort) During Reporting Period (June ¡V August 2019)
Survey Area
|
Dolphin
Monitoring
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
Primary Lines Only
|
Primary Lines Only
|
Northeast Lantau
|
Set 1 (3 & 6 Jun 2019)
|
0.00
|
0.00
|
Set 2 (10 & 13 Jun 2019)
|
0.00
|
0.00
|
Set 3 (16 & 18 Jul 2019)
|
0.00
|
0.00
|
Set 4 (22 & 24 Jul 2019)
|
0.00
|
0.00
|
Set 5 (13
& 14 Aug 2019)
|
0.00
|
0.00
|
Set 6 (20, 26 & 29 Aug 2019)
|
0.00
|
0.00
|
Northwest Lantau
|
Set 1 (3 & 6 Jun 2019)
|
3.73
|
9.32
|
Set 2 (10 & 13 Jun 2019)
|
0.00
|
0.00
|
Set 3 (16 & 18 Jul 2019)
|
0.00
|
0.00
|
Set 4 (22 & 24 Jul 2019)
|
0.00
|
0.00
|
Set 5 (13
& 14 Aug 2019)
|
0.00
|
0.00
|
Set 6 (20, 26 & 29 Aug 2019)
|
0.00
|
0.00
|
Table 3.5 Comparison of average dolphin encounter rates from impact
monitoring period (June ¡V August 2019) and baseline monitoring period (September
¡V November 2011)
Survey Area
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey
effort)
|
Reporting Period
|
Baseline Monitoring Period
|
Reporting Period
|
Baseline Monitoring Period
|
Northeast Lantau
|
0.0
|
6.00 ¡Ó 5.05
|
0.0
|
22.19 ¡Ó 26.81
|
Northwest Lantau
|
0.62 ¡Ó
1.52
|
9.85 ¡Ó 5.85
|
1.55 ¡Ó 3.80
|
44.66 ¡Ó 29.85
|
Notes:
1) The encounter rates deduced from the baseline monitoring period have been
recalculated based only on the survey effort and on-effort sighting data made
along the primary transect lines under favourable conditions.
2) ¡Ó denotes the standard deviation of the average
encounter rates.
3.5.21 In NEL,
the average dolphin encounter rates (both STG and ANI) in the present
three-month impact monitoring period were both zero with no on-effort sighting
being made, and such extremely low occurrence of dolphins in NEL have been
consistently recorded in the past 25 quarters of HKLR03 monitoring (Table 3.6). This is a serious concern
as the dolphin occurrence in NEL in the past few years (0.0-1.0 for ER(STG) and
0.0-3.9 for ER(ANI)) have remained exceptionally low when compared to the
baseline period (Table 3.6). Dolphins have been virtually absent from
NEL waters since August 2014, with only two lone dolphins sighted there on two
separate occasions despite consistent and intensive survey effort being
conducted in this survey area.
Table 3.6 Comparison of Average Dolphin Encounter Rates in Northeast Lantau
Survey Area from All Quarters of Impact Monitoring Period and Baseline
Monitoring Period (Sep ¡V Nov 2011)
Monitoring Period
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
September-November
2011 (Baseline)
|
6.00 ¡Ó 5.05
|
22.19 ¡Ó 26.81
|
December 2012-February 2013 (Impact)
|
3.14 ¡Ó 3.21
|
6.33 ¡Ó 8.64
|
March-May 2013 (Impact)
|
0.42 ¡Ó 1.03
|
0.42 ¡Ó 1.03
|
June-August 2013 (Impact)
|
0.88 ¡Ó 1.36*
|
3.91 ¡Ó 8.36*
|
September-November
2013 (Impact)
|
1.01 ¡Ó 1.59
|
3.77 ¡Ó 6.49
|
December
2013-February 2014 (Impact)
|
0.45 ¡Ó 1.10
|
1.34 ¡Ó 3.29
|
March-May 2014 (Impact)
|
0.00
|
0.00
|
June-August 2014 (Impact)
|
0.42 ¡Ó 1.04*
|
1.69 ¡Ó 4.15*
|
September-November 2014 (Impact)
|
0.00
|
0.00
|
December 2014-February 2015 (Impact)
|
0.00
|
0.00
|
March-May 2015 (Impact)
|
0.00
|
0.00
|
June-August 2015 (Impact)
|
0.44 ¡Ó 1.08*
|
0.44 ¡Ó 1.08*
|
September-November 2015 (Impact)
|
0.00
|
0.00
|
December 2015-February 2016 (Impact)
|
0.00
|
0.00
|
March-May 2016 (Impact)
|
0.00
|
0.00
|
June-August 2016 (Impact)
|
0.00*
|
0.00*
|
September-November
2016 (Impact)
|
0.00
|
0.00
|
December
2016-February 2017 (Impact)
|
0.00
|
0.00
|
March-May 2017 (Impact)
|
0.00
|
0.00
|
June-August 2017 (Impact)
|
0.00*
|
0.00*
|
September-November 2017 (Impact)
|
0.00
|
0.00
|
December
2017-February 2018 (Impact)
|
0.00
|
0.00
|
March-May 2018 (Impact)
|
0.00
|
0.00
|
June-August 2018 (Impact)
|
0.00*
|
0.00*
|
September-November 2018 (Impact)
|
0.00
|
0.00
|
December
2018-February 2019 (Impact)
|
0.00
|
0.00
|
March-May 2019 (Impact)
|
0.00
|
0.00
|
June-August 2019 (Impact)
|
0.00*
|
0.00*
|
Notes:
1) The encounter rates deduced from the baseline monitoring period have been
recalculated based only on survey effort and on-effort sighting data made along
the primary transect lines under favourable conditions.
2) ¡Ó denotes the standard deviation of the average
encounter rates.
3) The encounter rates in summer months were in blue and marked with
asterisk.
3.5.22 On the
other hand, the average dolphin encounter rates (STG and ANI) in NWL during the
present impact phase monitoring period (reductions of 93.7% and 96.5%
respectively) were only tiny fractions of the ones recorded during the
three-month baseline period, indicating a dramatic decline in dolphin usage of
this survey area as well during the present impact phase period (Table 3.7).
Table 3.7 Comparison of Average Dolphin Encounter Rates in Northwest
Lantau Survey Area from All Quarters of Impact Monitoring Period and Baseline
Monitoring Period (Sep ¡V Nov 2011)
Monitoring
Period
|
Encounter rate
(STG)
(no. of
on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate
(ANI)
(no. of dolphins from all on-effort sightings
per 100 km of survey effort)
|
September-November 2011 (Baseline)
|
9.85 ¡Ó 5.85
|
44.66 ¡Ó 29.85
|
December 2012-February 2013 (Impact)
|
8.36 ¡Ó 5.03
|
35.90 ¡Ó 23.10
|
March-May 2013 (Impact)
|
7.75 ¡Ó 3.96
|
24.23 ¡Ó 18.05
|
June-August 2013 (Impact)
|
6.56 ¡Ó 3.68*
|
27.00 ¡Ó 18.71*
|
September-November 2013 (Impact)
|
8.04 ¡Ó 1.10
|
32.48 ¡Ó 26.51
|
December 2013-February 2014 (Impact)
|
8.21
¡Ó 2.21
|
32.58
¡Ó 11.21
|
March-May 2014 (Impact)
|
6.51 ¡Ó 3.34
|
19.14 ¡Ó 7.19
|
June-August 2014 (Impact)
|
4.74 ¡Ó 3.84*
|
17.52 ¡Ó 15.12*
|
September-November 2014 (Impact)
|
5.10 ¡Ó 4.40
|
20.52 ¡Ó 15.10
|
December 2014-February 2015 (Impact)
|
2.91 ¡Ó 2.69
|
11.27 ¡Ó 15.19
|
March-May 2015 (Impact)
|
0.47 ¡Ó 0.73
|
2.36 ¡Ó 4.07
|
June-August 2015 (Impact)
|
2.53 ¡Ó 3.20*
|
9.21 ¡Ó 11.57*
|
September-November 2015 (Impact)
|
3.94 ¡Ó 1.57
|
21.05 ¡Ó 17.19
|
December 2015-February 2016 (Impact)
|
2.64 ¡Ó 1.52
|
10.98 ¡Ó 3.81
|
March-May 2016 (Impact)
|
0.98 ¡Ó 1.10
|
4.78 ¡Ó 6.85
|
June-August 2016 (Impact)
|
1.72 ¡Ó 2.17*
|
7.48 ¡Ó 10.98*
|
September-November 2016 (Impact)
|
2.86 ¡Ó 1.98
|
10.89 ¡Ó 10.98
|
December 2016-February 2017 (Impact)
|
3.80 ¡Ó 3.79
|
14.52 ¡Ó 17.21
|
March-May 2017 (Impact)
|
0.93 ¡Ó 1.03
|
5.25 ¡Ó 9.53
|
June-August 2017 (Impact)
|
2.20 ¡Ó 2.88*
|
6.58 ¡Ó 8.12*
|
September-November 2017 (Impact)
|
3.12 ¡Ó 1.91
|
10.35 ¡Ó 9.66
|
December 2017-February 2018 (Impact)
|
4.75 ¡Ó 2.26
|
15.73 ¡Ó 15.94
|
March-May 2018 (Impact)
|
2.88 ¡Ó 4.81
|
11.12 ¡Ó 22.46
|
|
June-August 2018 (Impact)
|
1.16 ¡Ó 1.39*
|
2.87 ¡Ó 3.32*
|
|
September-November 2018 (Impact)
|
1.51 ¡Ó 2.25
|
2.70 ¡Ó 3.78
|
|
December 2018-February 2019 (Impact)
|
2.40 ¡Ó 1.88
|
7.95 ¡Ó 6.60
|
|
March-May 2019 (Impact)
|
1.13 ¡Ó 1.39
|
2.54 ¡Ó 3.00
|
|
June-August 2019 (Impact)
|
0.62 ¡Ó 1.52*
|
1.55 ¡Ó 3.80*
|
|
Notes:
1) The encounter rates deduced from the
baseline monitoring period have been recalculated based only on survey effort
and on-effort sighting data made along the primary transect lines under
favourable conditions.
2) ¡Ó denotes the standard deviation of the average
encounter rates.
3) The encounter rates in summer months were in
blue and marked with asterisk.
3.5.23 Notably,
when comparing among the seven quarterly periods in summer months since 2013,
the quarterly encounter rates in the summer of 2019 plummeted to the lowest
level. (Table
3.7). In fact, this quarterly period has also recorded the lowest ER(ANI)
ever during the HKLR03 construction period. Such dramatic drop in dolphin occurrence
in NWL in recent years should raise serious concerns, and such temporal trend
should be closely monitored in the upcoming monitoring quarters as the
construction activities of HZMB works will soon be completed in coming months.
3.5.24 A two-way
ANOVA with repeated measures and unequal sample size was conducted to examine
whether there were any significant differences in the average encounter rates
between the baseline and impact monitoring periods. The two variables that were examined
included the two periods (baseline and impact phases) and two locations (NEL
and NWL).
3.5.25 For the
comparison between the baseline period and the present quarter (27th
quarter of the impact phase being assessed), the p-values for the differences
in average dolphin encounter rates of STG and ANI were 0.0011 and 0.0062
respectively. If the alpha value is set at 0.05, significant differences were
detected between the baseline and present quarters in both the average dolphin
encounter rates of STG and ANI.
3.5.26 For the
comparison between the baseline period and the cumulative quarters in impact
phase (i.e. the first 27 quarters of the impact phase being assessed), the
p-values for the differences in average dolphin encounter rates of STG and ANI
were 0.000000 and 0.000000 respectively.
Even if the alpha value is set at 0.00001, significant differences were
still detected in both the average dolphin encounter rates of STG and ANI (i.e.
between the two periods and the locations ).
3.5.27 As indicated
in both dolphin distribution patterns and encounter rates, dolphin usage has
been significantly reduced in both NEL and NWL survey areas during the present
quarterly period when compared to the baseline period, and such low occurrence
of dolphins has also been consistently documented in previous quarters of the
past five years throughout the HZMB construction.
3.5.28 The significant decline in dolphin usage of North
Lantau region raises serious concern, as the timing of the decline in dolphin
usage in North Lantau waters coincided well with the construction schedule of
the HZMB-related projects (Hung 2018). Not only there has been no sign of
recovery of dolphin usage, such usage has continued to fall even though almost
all marine works associated with the HZMB construction have been completed, and
the Brothers Marine Park has been established in late 2016 as a compensation
measure for the permanent habitat loss in association with the HKBCF
reclamation works.
Group Size
3.5.29 Group
size of Chinese White Dolphins ranged from two to three individuals per group
in North Lantau region during June to August 2019. The average dolphin group
sizes from these three months were compared with the ones deduced from the
baseline period in September to November 2011, as shown in Table 3.8.
Table 3.8 Comparison of Average Dolphin Group
Sizes between Reporting Period (June ¡V August 2019) and Baseline Monitoring
Period (Sep ¡V Nov 2011)
Survey Area
|
Average
Dolphin Group Size
|
Reporting
Period
|
Baseline
Monitoring Period
|
Overall
|
2.00
¡Ó 1.41 (n = 4)
|
3.72
¡Ó 3.13 (n = 66)
|
Northeast Lantau
|
---
|
3.18 ¡Ó 2.16 (n = 17)
|
Northwest Lantau
|
2.00
¡Ó 1.41 (n = 4)
|
3.92
¡Ó 3.40 (n = 49)
|
Note:
1) ¡Ó denotes the standard deviation of the
average group size.
3.5.30 The
average dolphin group size in NWL waters during June to August 2019 was much
lower than the one recorded during the three-month baseline period, but it should
be noted that the sample size of only four dolphin groups in the present
quarter was a tiny fraction of the sample size of 66 dolphin groups sighted
during the baseline period (Table 3.8).
3.5.31 Notably,
all four groups were small with 1-4 individuals per group only (Annex II of Appendix J).
Habitat
Use
3.5.32 From June to August 2019, only three
grids in North Lantau waters recorded dolphin occurrences during on-effort
search. The only grid with
moderately high dolphin density was located near Black Point (Figures
3a and 3b of Appendix
J). In contrast, the other two grids only
recorded moderately low DPSE
values.
3.5.33 Notably, all grids near HKLR03/HKBCF reclamation
sites as well as TMCLKL alignments did not record any presence of dolphins at
all during on-effort search in the present quarterly period (Figures 3a and 3b of Appendix J).
3.5.34
It should be
emphasized that the amount of survey effort collected in each
grid during the three-month period was fairly low (6-12 units of survey effort
for most grids), and therefore the habitat use pattern derived from the
three-month dataset should be treated with caution. A more complete picture of
dolphin habitat use pattern should be examined when more
survey effort for each grid is collected throughout the impact phase monitoring programme.
3.5.35 When compared with the habitat use patterns during
the baseline period, dolphin usage in NEL and NWL has drastically diminished in
both areas during the present impact monitoring period (Figure
4 of Appendix
J). During the baseline period, many grids
between Siu Mo To and Shum Shui Kok in NEL recorded
moderately high to high dolphin densities, which was in stark contrast to the
complete absence of dolphins there during the present impact phase period (Figure
5 of Appendix J).
3.5.36 The density patterns were also drastically
different in NWL between the baseline and impact phase monitoring periods, with
high dolphin usage recorded throughout the area during the baseline period,
especially around Sha Chau, near Black Point, to the west of the airport, as
well as between Pillar Point and airport platform. In contrast, only one grid
with moderately high dolphin density was located near Black Point during the
present impact phase period (Figure 5 of Appendix J).
Mother-calf Pairs
3.5.37 During the present quarterly period, no young
calf was sighted at all among the five groups of dolphins .
Activities and Associations with Fishing Boats
3.5.38 One of the four dolphin groups was engaged in
feeding activity, while none of them was engaged in socializing, traveling or
milling/resting activity during the three-month study period. The lone group engaged in feeding
activity was sighted at the southwestern corner of the NWL survey area (Figure
5 of Appendix
J)..
3.5.39 Notably, the percentage of sightings associated with
feeding activities (25.0%) was higher than the one recorded during the baseline
period (11.6%). However, it should
be noted the sample size on the total number of dolphin sightings during the present
quarter (four dolphin groups) was only a small fraction of the one during the
baseline period (66 dolphin groups).
3.5.40 Moreover,
none of the groups was found to be associated with any operating fishing
vessel during the present impact phase period.
Summary Photo-identification works
3.5.41 From June
to August 2019, roughly 300 digital photographs of Chinese White Dolphins were
taken during the impact phase monitoring surveys for the photo-identification
work.
3.5.42 In
total, six individuals sighted six times altogether were identified (see
summary table in Appendix III of Appendix J and photographs of identified individuals in Appendix IV of Appendix J). All six
individuals were re-sighted only once during the three-month monitoring period (Annex III of Appendix J).
3.5.43 Notably,
one of these individuals (NL123) was sighted in WL waters during the HKLR09
monitoring surveys from the same three-month period of June to August 2019.
Individual range use
3.5.44 Ranging
patterns of the six individuals identified during the three-month study period
were determined by fixed kernel method, and are shown in Annex V of Appendix J.
3.5.45 Besides
NL293 and WL218, the other four identified dolphins sighted in the present
quarter were mostly utilizing NWL waters as in the past, and they have
completely avoided NEL waters where two of them (NL123 and NL136) have utilized
as their core areas in the past (Annex V
of Appendix
J). This is in contrary to the extensive
movements between NEL and NWL survey areas observed in the earlier impact
monitoring quarters as well as the baseline period.
3.5.46 Moreover,
in contrary to previous monitoring quarters, only one of the six individuals
(NL123) have extended their range use to WL waters during the summer quarter of
2019.
Action Level / Limit Level Exceedance
3.5.47 There was a Limit Level exceedance of dolphin
monitoring for the quarterly monitoring data (between June
2019 and August 2019). According to the contractor¡¦s information, the
marine activities undertaken for HKLR03 during the quarter of June 2019 to
August 2019 included seawall construction.
3.5.48 There is no evidence showing the current LL
non-compliance directly related to the construction works of HKLR03 (where the
amounts of working vessels for HKLR03 have been decreasing), although the
generally increased amount of vessel traffic in NEL during the impact phase has
been partly contributed by HKLR03 works since October 2012. It should also be
noted that work area under HKLR03 (adjoining the Airport Island) situates in
waters which has rarely been used by dolphins in the past, and the working
vessels under HKLR03 have been travelling from source to destination in
accordance with the Marine Travel Route to minimize impacts on Chinese White
Dolphin (CWD). In addition, the contractor will implement proactive mitigation
measures such as avoiding anchoring at Marine Department¡¦s designated anchorage
site ¡V Sham Shui Kok Anchorage (near Brothers Island)
as far as practicable.
3.5.49 According to Monitoring of Chinese White Dolphins in
Southwest Lantau Waters ¡V Fourth Quarterly Report (December 2015 to February
2016) which is available on ENPO¡¦s website, with their primary ranges centered
in North and West Lantau waters, some individuals showed apparent range shifts
or extensions to Southwest Lantau waters in 2015-16. For example, three individual dolphins
(NL120, WL46 and WL221) indicated obvious shifts in their range use from NWL to
West Lantau (WL) and Southwest Lantau (SWL) waters. Moreover, many individuals
(e.g. NL212, NL260, WL200, SL55, WL232, WL237 and WL265) have extended their
ranges from WL waters to SWL waters.
It remains to be seen whether some of these individuals have permanently
shifted their ranges away from their primary ranges in North Lantau or begin to
spend more times in SWL waters as part of their ranges.
3.5.50 ENPO updated that the Hong Kong-Zhuhai-Macao Bridge
Authority (HZMBA) for the Mainland section of Hong Kong-Zhuhai-Macao Bridge
(HZMB) has commenced an interim survey on fisheries resources and CWD in the
Mainland waters. ENPO presented the preliminary findings of the HZMBA interim
survey on CWD sighting and photo-identification works which provide solid
evidence that some CWD that were previously more often sighted in HK waters
have expanded their ranges into the Mainland waters, and some with reduced
usage in HK waters. These preliminary data were mentioned in Monitoring of
Chinese White Dolphins in Southwest Lantau Waters ¡V Fourth Quarterly Report
(December 2015 to February 2016) which is available on ENPO¡¦s website.
3.5.51 A two-way ANOVA with repeated measures and unequal
sample size was conducted to examine whether there were any significant
differences in the average encounter rates between the baseline and impact
monitoring periods. The two variables that were examined included the two
periods (baseline and impact phases) and two locations (NEL and NWL).
3.5.52 For the comparison between the baseline period and
the present quarter (27th quarter of the impact phase being
assessed), the p-values for the differences in average dolphin encounter rates
of STG and ANI were 0.0011 and 0.0062 respectively. If the alpha value is set at 0.05,
significant differences were detected between the baseline and present quarters
in both the average dolphin encounter rates of STG and ANI.
3.5.53 For comparison between the baseline period and the
cumulative quarters in impact phase (i.e. first 27 quarters of the impact phase
being assessed), the p-values for the differences in average dolphin encounter
rates of STG and ANI were 0.000000 and 0.000000 respectively. Even if the alpha
value is set at 0.00001, significant differences were still detected in both
the average dolphin encounter rates of STG and ANI (i.e. between the two
periods and the locations).
3.5.54 The AFCD
monitoring data during June to August 2019 has been reviewed by the dolphin
specialist. During the same quarter, no dolphin was sighted from 67.58 km of
survey effort on primary lines in NEL, while only one group of one dolphin was
sighted from 95.47 km of survey effort on primary lines in NWL. This review has
confirmed that the rare occurrence of dolphins reported by the HKLR03
monitoring surveys in summer 2019 in NEL and NWL survey area is accurate.
3.5.55
All dolphin protective
measures are fully and properly implemented in accordance with the EM&A
Manual. According to the Regular Marine Travel Route Plan, the travelling speed
of vessels must not exceed 5 knots when crossing the edge of the Brothers
Marine Park. The Contractor will continue to provide training for skippers to
ensure that their working vessels travel from source to destination to minimize
impacts on Chinese White Dolphin and avoid anchoring at Marine Department¡¦s
designated anchorage site - Sham Shui Kok Anchorage
(near Brothers Island) as far as practicable. Also, it is recommended to complete the marine
works of the Contract as soon as
possible so as to reduce the overall duration of impacts and allow the dolphins
population to recover as early as possible.
3.5.56 It was concluded that the HZMB works is one of the
contributing factors affecting the dolphins. It was also concluded the
contribution of impacts due to the HZMB works as a whole (or individual marine
contracts) cannot be quantified nor separate from the other stress factors.
3.5.57 The dolphin specialists of the projects confirmed
that the CWD sighting around the North of Sha Chau and Lung Kwu
Chau Marine Park (SCLKCMP) has significantly decreased, and it was likely
related to the re-routing of high speed ferry (HSF) from Skypier.
3.5.58 ET will keep reviewing the implementation status of
the dolphin related mitigation measures and remind the contractor to implement
the relevant measures.
3.5.59 It was recommended that the marine works of HZMB
projects should be completed as soon as possible so as to reduce the overall
duration of impacts and allow the dolphins population to recover as early as
possible.
3.5.60 It was also recommended that the marine works
footprint (e.g., reduce the size of peripheral silt curtain) and vessels for
the marine works should be reduced as much as possible, and vessels idling /
mooring in other part of the North Lantau shall be avoided whenever possible.
3.5.61 HyD updated that the
draft map of the proposed Brothers Marine Park (BMP) was gazetted
in February 2016. ENPO updated that the BMP was approved by the Chief Executive
in the Executive Council in August 2016. The ETs were reminded to update the
BMP boundary in the Regular Marine Travel Route (RMTR) Plan. The BMP was
designated on 30 December 2016. It was suggested that the protection measures
(e.g. speed limit control) for the approved BMP shall be brought forward so as
to provide a better habitat for dolphin recovery. It was noted that under the
latest RMTR Plan, the contractors have committed to reduce the vessel speed in
BMP.
3.5.62 The marine travel route will shift along the edge of
the Brothers Marine Park as much as practical under the RMTR Plan. It was noted
that even though marine vessels may moor within the mooring site of BMP,
commercial activities including loading / unloading / transshipment are not
allowed except a permit is obtained. The HZMB works vessels were recommended to
avoid the BMP.
3.5.63 It was noted that starting from January 2016, HSF
from the SkyPier will be re-routed north to the
northern edged of the Sha Chau and Lung Kwu Chau
Marine Park which currently has the highest density of CWD in the NWL. While
the HSF will reduce speed to 15 knots, the associated disturbance may still
affect CWD in the area. It was implied that the CWDs in the area shall be
closely followed.
3.5.64 There was a discussion on exploring possible further
mitigation measures, for example, controlling the underwater noise. It was noted
that the EIA reports for the projects suggested several mitigation measures,
all of which have been implemented.
3.6
Mudflat
Monitoring Results
Sedimentation Rate
Monitoring
3.6.1 The baseline sedimentation rate monitoring was in September 2012 and
impact sedimentation rate monitoring was undertaken on 20 June 2019. The mudflat surface levels at the four
established monitoring stations and the corresponding XYZ HK1980 GRID
coordinates are presented in Table 3.9 and Table 3.10.
Table 3.9 Measured
Mudflat Surface Level Results
|
Baseline Monitoring
(September 2012)
|
Impact Monitoring
(June 2019)
|
Monitoring Station
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
810291.160
|
816678.727
|
0.950
|
810291.159
|
816678.729
|
1.123
|
S2
|
810958.272
|
815831.531
|
0.864
|
810958.255
|
815831.504
|
0.983
|
S3
|
810716.585
|
815953.308
|
1.341
|
810716.575
|
815953.300
|
1.439
|
S4
|
811221.433
|
816151.381
|
0.931
|
811221.460
|
816151.406
|
1.088
|
Table 3.10 Comparison
of Measurement
|
Comparison of measurement
|
Remarks and
Recommendation
|
Monitoring Station
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
-0.001
|
0.002
|
0.173
|
Level
continuously increased
|
S2
|
-0.017
|
-0.027
|
0.119
|
Level continuously increased
|
S3
|
-0.010
|
-0.008
|
0.098
|
Level continuously increased
|
S4
|
0.027
|
0.025
|
0.157
|
Level continuously increased
|
3.6.2
This measurement result was generally and relatively higher than the
baseline measurement at S1, S2, S3 and S4. The mudflat level is continuously
increased.
Water Quality
Monitoring
3.6.3
The mudflat monitoring covered water quality
monitoring data. Reference was made to the water quality monitoring data of the
representative water quality monitoring station (i.e. SR3(N)) as in the
EM&A Manual. The water quality monitoring location (SR3(N)) is shown in Figure 2.1.
3.6.4 Impact water quality
monitoring in San Tau (monitoring station SR3(N)) was conducted in June 2019.
The monitoring parameters included dissolved oxygen (DO), turbidity and
suspended solids (SS).
3.6.5 The
Impact monitoring result for SR3(N) were extracted and summarised in Table 3.11:
Table 3.11 Impact
Water Quality Monitoring Results (Depth Average)
Date
|
Mid Ebb Tide
|
Mid Flood Tide
|
DO (mg/L)
|
Turbidity (NTU)
|
SS (mg/L)
|
DO (mg/L)
|
Turbidity (NTU)
|
SS (mg/L)
|
03-Jun-2019
|
6.8
|
4.2
|
5.4
|
6.1
|
1.9
|
4.3
|
05-Jun-2019
|
6.8
|
5.4
|
5.9
|
6.0
|
5.5
|
3.0
|
07-Jun-2019
|
6.8
|
5.5
|
8.2
|
6.4
|
6.6
|
7.4
|
10-Jun-2019
|
6.7
|
3.4
|
5.0
|
7.2
|
5.4
|
6.4
|
12-Jun-2019
|
6.3
|
4.7
|
6.6
|
6.2
|
4.8
|
7.0
|
14-Jun-2019
|
5.9
|
4.9
|
3.0
|
6.2
|
3.3
|
5.4
|
17-Jun-2019
|
7.1
|
7.5
|
6.2
|
5.5
|
5.3
|
5.5
|
19-Jun-2019
|
6.4
|
5.0
|
9.7
|
5.9
|
2.5
|
6.6
|
21-Jun-2019
|
7.7
|
4.3
|
3.6
|
7.9
|
4.9
|
4.7
|
24-Jun-2019
|
7.1
|
3.3
|
3.8
|
7.2
|
2.4
|
3.0
|
26-Jun-2019
|
6.1
|
3.5
|
3.7
|
6.3
|
3.3
|
3.2
|
28-Jun-2019
|
6.7
|
3.8
|
3.5
|
6.9
|
6.5
|
5.7
|
Average
|
6.7
|
4.6
|
5.4
|
6.5
|
4.4
|
5.2
|
Mudflat Ecology
Monitoring
Sampling Zone
3.6.1 n order to collect
baseline information of mudflats in the study site, the study site was divided
into three sampling zones (labeled as TC1, TC2, TC3) in Tung Chung Bay and one
zone in San Tau (labeled as ST) (Figure 2.1 of Appendix O). The horizontal 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 O). Survey of horseshoe crabs, seagrass beds
and intertidal communities were conducted in every sampling zone. The present
survey was conducted in June 2019 (totally 4 sampling days on 4th, 5th,
17th, 18th June 2019).
3.6.2 Since the field survey of Jun.
2016, increasing number of trashes and even big trashes (Figure 2.3 of Appendix O) were found in every sampling zone. It raised a concern about the solid
waste dumping and current-driven waste issues in Tung Chung Bay. Respective
measures (e.g. manual clean-up) should be implemented by responsible government
agency units.
Horseshoe Crabs
3.6.3 Active search method was adopted
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 hour 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 4th, 5th, 17th, 18th
June 2019, which were hot and humid days.
3.6.4 In June 2017, a big horseshoe
crab was tangled by a trash gill net in ST mudflat (Figure 2.3 of Appendix O). 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 units .
Seagrass Beds
3.6.5 Active
search method was adopted 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 4th
(for TC2), 5th (for TC1), 17th (for TC3) and 18th
(for ST) June 2019, which were hot and humid days.
Intertidal Soft Shore Communities
3.6.6
The intertidal
soft shore community surveys were conducted in low tide period on 4th
(for TC2), 5th (for TC1), 17th (for TC3) and 18th
(for ST) June 2019. In every sampling zone, three 100m horizontal transect
lines were laid at high tidal level (H: 2.0m above C.D.), mid tidal level (M:
1.5m above C.D.) and low tidal level (L: 1.0m above C.D.). Along every
horizontal transect line; ten random quadrats (0.5 m x 0.5m) were placed.
3.6.7
Inside a quadrat, any visible
epifauna was collected and was 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 was collected
and identified. Finally, the top 5 cm surface sediment was dug for visible
infauna in the quadrat regardless of hand core sample was taken.
3.6.8
All collected fauna were
released after recording except some tiny individuals that were too small to be
identified on site. These tiny individuals were taken to laboratory for
identification under dissecting microscope.
3.6.9
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).
3.6.10 Data Analysis
3.6.11
Data collected from direct search and core sampling
was pooled in every quadrat for data analysis. Shannon-Weaver Diversity Index (H¡¦) and Pielou¡¦s
Species Evenness (J) were calculated
for every quadrat using the formulae below,
H¡¦= -£U ( Ni / N ) ln ( Ni / N ) (Shannon and Weaver, 1963)
J = H¡¦ / ln S, (Pielou, 1966)
where S is the total number of species in the sample, N is the total
number of individuals, and Ni is the number of individuals of the ith species.
Mudflat Ecology Monitoring Results and Conclusion
Horseshoe Crabs
3.6.12 10 individuals of horseshoe crab, Tachypleus tridentatus,
were found in present survey. The recorded individuals were mainly distributed
along the shoreline from TC3 to ST. All of them were observed on similar
substratum (fine sand or soft mud, slightly submerged). No horseshoe crab was
recorded at TC1 and TC2 in present survey. Since all found target fauna were
large audit individuals (prosomal width >100mm), their records are excluded
from the data analysis to avoid mixing up with juvenile population living on
intertidal habitat. Photo records of the observed horseshoe crab are shown in Figure 3.1 of Appendix O and the present survey result regarding
horseshoe crab are presented in Table 3.1 of Appendix O. The complete survey records are presented
in Annex II of Appendix O.
3.6.13 More individuals (7 ind.) were found in TC3
with average body size 189mm (150 ¡V 220mm). In ST, there were only 3
individuals with average body size 167mm (140 ¡V 180mm) recorded. These two
sampling zones were very low in search record (0.5 - 1.2 ind. hr-1.
Person-1).
3.6.14 A total of 3 mating pairs of
horseshoe crabs were nearly burrowing in soft mud at low tidal level (0.5 ¡V
1.0m above C.D.) at TC3 and ST (Figure
3.2 of Appendix O). In TC3, 2 mating pairs with
large body sizes (prosomal width: Male 150mm and Female 200mm; Male 180mm and
Female 220mm) were found while a mating pair was noted in ST (prosomal width:
Male 140mm and Female 180mm). The mating pair indicated the breeding of
horseshoe crab could be possible along the coast of Tung Chung Wan, as long as
suitable substratum was available. In March to June 2019 (present survey), no
horseshoe crab juveniles (prosomal width <100mm) were recorded in TC3 and
ST. All recorded horseshoe crabs were large audit individuals (prosomal width
>100mm) or mating pairs which were all excluded from the data analysis. It
is believed that more tiny individuals (i.e. newly hatched) would be found due
to the stable growth of juveniles after the spawning season (Figure 3.3 of Appendix O).
3.6.15 Despite of mating pairs, 3 large
individuals with average body size 190mm were found in TC3 and one large
individual with body size 180mm was noted in ST (Figure 3.4 of Appendix O). Based
on its size, 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. This large individual might move onto intertidal shore
occasionally during high tide for foraging and breeding. Because it
should be
inhabiting sub-tidal habitat most of the time. This record is excluded from the data analysis to avoid mixing up
with juvenile population living on intertidal habitat.
3.6.16 No marked individual of horseshoe crab was recorded in the present
survey. Some marked individuals were found in the previous surveys of September
2013, March 2014 and September 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 crabs
population might be restored in the natural habitat. Through a personal
conversation with Prof. Shin, about 100 individuals were released in the
sampling zone ST on 20 June 2013. All of them were marked with color tape and
internal chip detected by specific chip sensor. There should be second round of
release between June and September 2014 since new marked individuals were found
in the survey of September 2014.
3.6.17
The
artificial bred individuals, if found, would be excluded from the results of
present monitoring programme in order to reflect the
changes of natural population. However, the mark on their prosoma might have
been detached during moulting after a certain period
of release. The artificially released individuals were no longer
distinguishable from the natural population without the specific chip sensor.
The survey data collected would possibly cover both natural population and
artificially bred individuals.
Population
difference among the sampling zones
3.6.18 In
present survey, 7 individuals of horseshoe crab were observed in TC3 and 1
individual of that was found in ST. No target fauna was noted in TC1 and TC2.
Although there were horseshoe crabs found in TC3 and ST, all of them were large
audit individuals which were excluded from the analysis. The search record for
TC3and ST was 1.2 ind. hr-1person-1and 0.5 ind. hr-1
person-1, respectively. Figure 3.5 and 3.6
of Appendix
O the changes of number of individuals, mean prosomal width and search
record of horseshoe crabs Carcinoscorpius rotundicauda and Tachypleus tridentatusin respectively in each
sampling zone throughout the monitoring period.
3.6.19 To consider the entire monitoring
period for TC3 and ST, medium to high search records (i.e. number of
individuals) of both species (Carcinoscorpius rotundicauda and Tachypleus tridentatusin) were usually found in wet
season (June and September). The search record of ST was higher from September 2012
to June 2014 while it was replaced by TC3 from September 2014 to June 2015. The
search records were similar between two sampling zones from September 2015 to
June 2016. In September 2016, the search record of Carcinoscorpius rotundicauda
in ST was much higher than TC3. From March to June 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 September 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 June and September 2017, to be discussed in 'Seagrass survey'
section). From December 2017 to
September 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.
3.6.20 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 June 2016.
3.6.21 About the body size, larger
individuals of Carcinoscorpius rotundicauda
were usually found in ST and TC1 relative to that in TC3 from September 2012 to
June 2017. But the body size was higher in TC3 and ST followed by TC1 from
September 2017 to March 2019. For Tachypleus tridentatus, larger individuals were usually found in ST
and TC3 followed by TC1 throughout the monitoring period. In June 2019 (present survey), all found
horseshoe crabs were large individuals and mating pairs. It is believed that
the sizes of the horseshoe crabs would be decrease and gradually rise afterward
due to the stable growth of juveniles after the spawning season.
3.6.22 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 TC2were 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
3.6.23
Throughout the monitoring period, the search
records of horseshoe crabs were fluctuated and at moderate ¡V very low level in
June (Figures
3.4 and 3.5 of Appendix O).
Low ¡V Very low
search record was found in June 2013, totally 82 ind. of Tachypleus tridentatus and 0 ind. of Carcinoscorpius rotundicauda were
found in TC1, TC3 and ST. Compare with the search record of June 2013, the
numbers of Tachypleus tridentatus
were gradually decreased in June 2014 and 2015 (55 ind. in 2014 and 18 ind. in
2015); the number of Carcinoscorpius
rotundicauda raise to 88 and 66 ind. in June 2014
and 2015 respectively. In June 2016, the search record increased about 3 times
compare with June 2015. In total, 182 ind. of Carcinoscorpius rotundicauda
and 47 ind. of Tachypleus tridentatus
were noted, respectively. Then, the search record was similar to June 2016. The
number of recorded Carcinoscorpius rotundicauda(133
ind.) slightly dropped in June 2017. However, that of Tachypleus tridentatus rapidly increased (125
ind.). In June 2018, the search record was low to moderate while the numbers of
Tachypleus tridentatus
dropped sharply (39 ind.). In March 2019, 3 ind.of Carcinoscorpius rotundicauda
were observed in TC2. However, all of them were large individuals (prosomal
width >100mm), their records are excluded from the data analysis to avoid
mixing up with the juvenile population living on intertidal habitat. Throughout
the monitoring period, similar distribution of horseshoe crabs population were
found in March. Most of the horseshoe crabs were found in TC3 and ST.
3.6.24 The search record of horseshoe crab declined
obviously in all sampling zones during dry season especially December (Figures
3.5 and 3.6 of Appendix
O) throughout the monitoring period. 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-1person-1 and 0.00 ind. hr-1
person-1 in wet season and dry season respectively (details see Li,
2008). Compare with the search record of December from 2012 to 2015, which of
December 2016 were much higher relatively. There were totally 70 individuals of
Carcinoscorpius rotundicauda
and 24 individuals of Tachypleus tridentatus in TC3 and ST. Since the survey was carried
in earlier December with warm and sunny weather (~22 ºC during dawn according
to Hong Kong Observatory database, Chek Lap Kok station on 5 December 2016), the horseshoe crab was
more active (i.e. move onto intertidal shore during high tide for foraging and
breeding) and easier to be found. 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 ºC
during dawn on 19 December). The horseshoe crab activity would decrease
gradually with the colder climate. In December of 2017 and 2018, very low
search records were found again as mentioned above.
3.6.25 From September 2012 to December
2013, Carcinoscorpius rotundicauda
was less common species relative to Tachypleus tridentatus. Only 4 individuals were ever recorded in
ST in December 2012. This species had ever been believed of very low density in
ST hence the encounter rate was very low. In March 2014, it was found in all
sampling zones with higher abundance in ST. Based on its average size (mean
prosomal width 39.28-49.81 mm), it indicated that breeding and spawning of this
species had occurred about 3 years ago along the coastline of Tung Chun Wan.
However, these individuals were still small while their walking trails were
inconspicuous. Hence there was no search record in previous sampling months.
Since March 2014, more individuals were recorded due to larger size and higher
activity (i.e. more conspicuous walking trail).
3.6.26 For Tachypleus tridentatus, sharp increase of number of
individuals was recorded in ST during the wet season of 2013 (from March to
September). According to a personal conversation with Prof. Shin (CityU), his monitoring team had recorded similar increase
of horseshoe crab population during wet season. It was believed that the
suitable ambient temperature increased its conspicuousness. However similar
pattern was not recorded in the following wet seasons. The number of
individuals increased in March and June 2014 and followed by a rapid decline in
September 2014. Then the number of individuals fluctuated slightly in TC3 and
ST until March 2017. Apart from natural mortality, migration from nursery soft
shore to subtidal habitat was another possible cause. Since the mean prosomal
width of Tachypleus tridentatus
continued to grow and reached about 50 mm since March 2014. Then it varied
slightly between 35-65 mm from September 2014 to March 2017.Most of the
individuals might have reached a suitable size (e.g. prosomal width 50-60 mm)
strong enough to forage in sub-tidal habitat. In June 2017, the number of
individuals increased sharply again in TC3 and ST. Although mating pair of Tachypleus tridentatus
was not found in previous surveys, there should be new round of spawning in the
wet season of 2016. The individuals might have grown to a more conspicuous size
in 2017 accounting for higher search record. In September 2017, moderate
numbers of individual were found in TC3 and ST indicating a stable population
size. In September 2018, the population size was lower while natural mortality
was the possible cause.
3.6.27 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
3.6.28 Figure
3.7 of Appendix O shows the changes of prosomal width of Carcinoscorpius rotundicauda
and Tachypleus tridentatus
in TC3. As mentioned above, Carcinoscorpius
rotundicauda was rarely found between September
2012 and December 2013 hence the data were lacking. In March 2014, the major
size (50% of individual records between upper (top box) and lower quartile
(bottom box)) ranged 40-60 mm while only few individuals were found. From March
2014 to September 2018, the median prosomal width (middle line of whole box)
and major size (whole box) decreased after March 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 June to March 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.
3.6.29 For Tachypleus tridentatus,
the major size ranged 20-50 mm while the number of individuals fluctuated from
September 2012 to June 2014. Then a slight but consistent growing trend was
observed from September 2014 to June 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 March to September 2016,
slight increasing trend of major size was noticed again. From December 2016 to
June 2017, similar increasing trend of major size was noted with much higher
number of individuals. It reflected new round of spawning. In September 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 June and
September 2017 (to be discussed in the 'Seagrass survey' section). From
December 2017 to September 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
3.6.30 Figure
3.8 of Appendix O shows the changes of prosomal width of Carcinoscorpius rotundicauda
and Tachypleus tridentatus
in ST. As mentioned above, Carcinoscorpius rotundicauda was rarely found between September 2012
and December 2013 hence the data were lacking. From March 2014 to September
2018, the size of major population decreased and more small individuals (i.e.
lower whisker) were recorded after June of every year. It indicated new round
of spawning. Also, there were similar increasing trends of body size from
September to June of next year between 2014 and 2017. It indicated a stable
growth of individuals. 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 March 2017. It reflected juveniles reaching this size would gradually
migrate to sub-tidal habitats.
3.6.31 For Tachypleus tridentatus, a consistent growing trend
was observed for the major population from December 2012 to December 2014
regardless of change of search record. The prosomal width increased from 15-30
mm to 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 March
to September 2015, the size of major population decreased slightly to a
prosomal width 40-60 mm. At the same time, the number of individuals decreased
gradually. It further indicated some of large juveniles might have migrated to
sub-tidal habitat, leaving the smaller individuals on shore. There was an
overall growth trend. In December 2015, two big individuals (prosomal width
89.27 mm and 98.89 mm) were recorded only while it could not represent the
major population. In March 2016, the number of individual was very few in ST
that no box plot could be produced. In June 2016, the prosomal width of major
population ranged 50-70 mm. But it dropped clearly to 30-40 mm in September
2016 followed by an increase to 40-50 mm in December 2016, 40-70 mm in March
2017 and 50-60mm in June 2017. Based on overall higher number of small
individuals from June 2016 to September 2017, it indicated another round of
spawning. From September 2017 to June 2018, the major size range increased
slightly from 40-50 mm to 45-60 mm indicating a continuous growth. In September
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.
3.6.32 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.
3.6.33 In
March to June 2019 (present survey), no horseshoe crab juveniles (prosomal
width <100mm) were recorded in TC3 and ST. All recorded horseshoe crabs were
large individuals (prosomal width >100mm) or mating pairs which were all
excluded from the data analysis. It is believed that the body size of horseshoe
crabs would be gradually increased due to the stable growth of juveniles after
the spawning season..
Impact of the HKLR
project
3.6.34 It was
the 27th survey of the EM&A programme
during construction period. Based on the monitoring results, no detectable
impact on horseshoe crab was revealed due to HKLR project. The population
change was mainly determined by seasonal variation, no abnormal phenomenon of
horseshoe crab individual, such as large number of dead individuals on the
shore) had been reported.
Seagrass Beds
3.6.35 Only seagrass species Halophila ovalis was found in present
survey, which was found in TC3 and ST. In ST, there were one small sized, one
medium -large sized and one large sized of seagrass beds found at tidal zone
1.5- 2.0 m above C.D. nearby mangroves plantation. The largest rand had area
~1100m2 in medium ¡V high vegetation coverage (60 - 70%). At close
vicinity, a small sized (~ 15 m2) and a medium sized (~ 114 m2)
of Halophila ovalis beds in high
vegetation coverage (90 ¡V 100%) were observed at tidal zone 1.5- 2.0 m above
C.D. Another seagrass species Zostera japonica
was not found in present survey. Table
3.2 of Appendix O summarizes the results of
present seagrass beds survey and the photograph records of the seagrass are
shown on Figure 3.9 of Appendix O.
The complete record throughout the monitoring period is presented in Annex III of Appendix O.
3.6.36 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 3.10
of Appendix O). 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 co-existed
with Halophila ovalis nearby the
mangrove strand at 2.0 m above C.D..
3.6.37 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
3.6.38 Figure
3.11 of Appendix O shows the changes of
estimated total area of seagrass beds in ST along the sampling months. For Zostera japonica, it was not recorded in the 1st
and 2nd surveys of monitoring programme.
Seasonal recruitment of few, small patches (total seagrass area: 10 m2) was
found in Mach 2013 that grew within the large patch of seagrass Halophila
ovalis. Then, the patch size increased and merged gradually with the warmer
climate from March to June 2013 (15 m2). However, the patch size
decreased and remained similar from September 2013 (4 m2) to March 2014 (3 m2).
In June 2014, the patch size increased obviously again (41 m2) with
warmer climate followed by a decrease between September 2014 (2 m2)
and December 2014 (5 m2). From March to June 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 September 2015
to June 2016, it was found coexisting with seagrass Halophila ovalis
with steady increasing patch size (from 44 m2 to 115 m2) and
variable coverage. In September 2016, the patch size decreased again to (38 m2)
followed by an increase to a horizontal strand (105.4 m2) in June
2017. And it did no longer co-exist with Halophila ovalis. Between
September 2014 and June 2017, an increasing trend was noticed from September to
June of next year followed by a rapid decline in September 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 September
2017 to June 2019 (present survey) while no patch of Zostera
japonica was found.
3.6.39
For
Halophila ovalis, it was recorded as 3-4 medium to large patches (area
18.9-251.7 m2; vegetation coverage 50-80%) beside the mangrove
vegetation at tidal level 2 m above C.D. in September 2012. The total seagrass
bed area grew steadily from 332.3 m2 in September 2012 to 727.4 m2
in December 2013. Flowers were observed in the largest patch during its
flowering period. In March 2014, 31 small to medium patches were newly recorded
(variable area 1-72 m2 per patch, vegetation coverage 40-80% per
patch) in lower tidal zone between 1.0 and 1.5 m above C.D. The total seagrass
area increased further to 1350 m2. In June 2014, these small and
medium patches grew and extended to each 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 September 2014, the total seagrass area declined sharply to 1111m2.
There were only 3-4 small to large patches (6-253 m2) at high tidal
level and 1large patch at low tidal level (786 m2). Typhoon or
strong water current was a possible cause (Fong, 1998). In September 2014,
there were two tropical cyclone records in Hong Kong (7th-8th September:
no cyclone name, maximum signal number 1; 14th-17th September:
Kalmaegi, maximum signal number 8SE) before the
seagrass survey dated 21stSeptember 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.
3.6.40 In
December 2014, all the seagrass patches of Halophila
ovalis disappeared in ST. Figure 3.12
of Appendix
O shows the difference of the original
seagrass beds area nearby the mangrove vegetation at high tidal level between
June 2014 and December 2014.Such rapid loss would not be seasonal phenomenon
because the seagrass beds at higher tidal level (2.0 m above C.D.) were present
and normal in December 2012 and 2013. According to Fong (1998), similar
incident had occurred in ST in the past. The original seagrass area had
declined significantly during the commencement of the construction and
reclamation works for the international airport at Chek
Lap Kok in 1992. The seagrass almost disappeared in
1995 and recovered gradually after the completion of reclamation works.
Moreover, incident of rapid loss of seagrass area was also recorded in another
intertidal mudflat in Lai Chi Wo in 1998 with unknown reason. Hence, Halophila ovalis was regarded as a
short-lived and r-strategy seagrass that could colonize areas in short period
but disappears quickly under unfavourable conditions
(Fong, 1998).
Unfavourable conditions
to seagrass Halophila
ovalis
3.6.41 Typhoon or strong water current
was suggested as one unfavorable condition to Halophila ovalis (Fong, 1998). As mentioned above, there were two
tropical cyclone records in Hong Kong in September 2014. The strong water
current caused by the cyclones might have given damage to the seagrass beds.
3.6.42 Prolonged light deprivation due
to turbid water would be another unfavorable condition. Previous studies
reported that Halophila ovalis had
little tolerance to light deprivation. During experimental darkness, seagrass
biomass declined rapidly after 3-6 days and seagrass died completely after 30
days. The rapid death might be due to shortage of available carbohydrate under
limited photosynthesis or accumulation of phytotoxic end products of anaerobic
respiration (details see Longstaff et al.,
1999). Hence the seagrass bed of this species was susceptible to temporary
light deprivation events such as flooding river runoff (Longstaff and Dennison,
1999).
3.6.43
In order to investigate any deterioration of water quality (e.g. more
turbid) in ST, the water quality measurement results at two closest monitoring
stations SR3 and IS5 of the EM&A programme were
obtained from the water quality monitoring team. Based on the results from June
to December 2014, the overall water quality was in normal fluctuation except
there was one exceedance of suspended solids (SS) at both stations in
September. On 10th September 2014, the SS concentrations measured
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 September 2014 (daily total rainfall at the
Hong Kong International Airport: 0-2.1 mm; extracted from the climatological
data of Hong Kong Observatory). The effect of upstream runoff on water quality
should be neglectable in that period. Moreover, the exceedance of water quality
was considered unlikely to be related to the contract works of HKLR according
to the ¡¥Notifications of Environmental Quality Limits Exceedances¡¦ provided by
the respective environmental team. The respective construction of seawall and
stone column works, which possibly caused turbid water, was carried out within
silt curtain as recommended in the EIA report. Moreover, there was no leakage
of turbid water, abnormity or malpractice recorded during water sampling. In
general, the exceedance of suspended solids concentration was considered to be
attributed to other external factors, rather than the contract works.
3.6.44
Based on the weather condition and water quality results in ST, the
co-occurrence of cyclone hit and turbid waters in September 2014 might have
combined the adverse effects on Halophila
ovalis that leaded to disappearance of this short-lived and r-strategy
seagrass species. Fortunately, Halophila
ovalis was a fast-growing species (Vermaat et al., 1995). Previous studies showed
that the seagrass bed could be recovered to the original sizes in 2 months
through vegetative propagation after experimental clearance (Supanwanid, 1996). Moreover it was reported to recover
rapidly in less than 20 days after dugong herbivory (Nakaoka
and Aioi, 1999).As mentioned, the disappeared
seagrass in ST in 1995 could recover gradually after the completion of
reclamation works for international airport (Fong, 1998).The seagrass beds of Halophila ovalis might recolonize in the
mudflat of ST through seed reproduction as long as there was no unfavourable condition in the coming months.
Recolonization of seagrass beds
3.6.45 Figure 3.12 of Appendix O shows the recolonization of seagrass bed in ST from December 2014
to June 2017. From March to June 2015, 2-3 small patches of Halophila ovalis were newly found
co-inhabiting with another seagrass species Zostera japonica. But the total patch area of Halophila ovalis was still very low compare with previous records.
The recolonization rate was low while cold weather and insufficient sunlight
were possible factors between December 2014 and March 2015. Moreover, it would
need to compete with seagrass Zostera japonica for
substratum and nutrient, because Zostera japonica had
extended and covered the original seagrass bed of Halophila ovalis at certain
degree. From June 2015 to March 2016, the total seagrass area of Halophila
ovalis had increased rapidly from 6.8 m2 to 230.63 m2. It
had recolonized its original patch locations and covered its competitor Zostera japonica. In June 2016, the total
seagrass area increased sharply to 4707.3m2. Similar to the previous
records of March to June 2014, the original patch area of Halophila ovalis 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 September 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
December 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 March to June 2017, the seagrass bed
area remained generally stable (12438-17046.5 m2) but the vegetation
coverage fluctuated (20-50% in March 2017 to 80-100% in June 2017). The whole
recolonization process took about 2.5 years.
Second disappearance of
seagrass bed
3.6.46 In September 2017, the whole seagrass bed of Halophila ovalis disappeared again along the shore of TC3 and ST (Figure 3.12 of Appendix O). Similar to the first disappearance of seagrass bed occurred between
September and December 2014, strong water current (e.g. cyclone) or
deteriorated water qualities (e.g. high turbidity) was the possible cause.
3.6.47 Between the survey periods of June and September 2017, there were
four tropical cyclone records in Hong Kong (Merbok in
12-13th, June; Roke in 23rd,
Jul.; Hato in22-23rd, Aug.; Pakhar in 26-27th, Aug.) (Online database of
Hong Kong Observatory). All of them reaches signal 8 or above, especially Hato with highest signal 10.
3.6.48 According to the water quality monitoring results (July to August
2017) of the two closest monitoring stations SR3 and IS5 of the respective
EM&A programme, the overall water quality was in
normal fluctuation. There was an exceedance of suspended solids (SS) at SR3 on
12 July 2017. The SS concentration reached 24.7 mg/L during mid-ebb tide, which
exceeded the Action Level (≤23.5 mg/L). But it 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.
3.6.49 Overall, the disappearance of seagrass beds in ST has believed the
cause of serial cyclone hit in July and August 2017. Based on previous
findings, the seagrass beds of both species were expected to recolonize in the
mudflat as long as the vicinal water quality was normal. The whole
recolonization process (from few, small patches to extensive strand) would be
gradually lasting at least 2 years. From December 2017 to March 2018, there was
still no recolonization of few, small patches of seagrass at the usual location
(Figure 3.12 of Appendix O). It was different from the previous round (March 2015 - June
2017). Until June 2018, the new seagrass patches with small-medium size 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 September 2018. Again, it was believed that
the decrease was due to the hit of the super cyclone in September 2018 (Mangkhuton 16th September, highest signal 10).
From December 2018 to June 2019 (present survey), the seagrass bed area
increased from 404 m2 to 1229 m2 while the vegetation
coverage are also increased. (December 2018: 5 ¡V 85%; March 2019: 50 ¡V 100% and
June 2019: 60 ¡V 100%). Relatively, the whole recolonization process would occur
slower than the previous round (more than 2 years).
Impact of the HKLR project
3.6.50 It was the 27th survey of the EM&A programme during construction
period. Throughout the monitoring period, the disappearance of seagrass beds
was believed the cause of cyclone hits rather than impact of HKLR project. The
seagrass bed is recolonizing since there has been a gradual increase in the size
and number of that after the hit of the super cyclone in September 2018.
Intertidal Soft
Shore Communities
Substratum
3.6.51 Table 3.3 and Figure 3.13 of Appendix O show the substratum types along the horizontal transect 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¡¦ (H: 90%; M: 70%) were recorded at high and mid tidal levels.
Relatively higher percentages of ¡¥Gravels and Boulders¡¦ (50%) and ¡¥Soft mud¡¦ (40%)
were recorded at low tidal level.
¡P
In TC2, high percentages of ¡¥Gravels and Boulders¡¦ (H: 80%; M: 60%) were
recorded at high and mid tidal levels. Relatively higher percentages of
¡¥Gravels and Boulders¡¦ (50%) and ¡¥Soft mud¡¦ (40%) were recorded at low tidal
level.
¡P
In TC3, higher percentage of ¡¥Gravels and Boulders¡¦ (50%) was recorded followed
by ¡¥Sand¡¦ (30%) at high tidal level. At mid tidal level, higher percentages of
¡¥Gravels and Boulders¡¦ (40%) and ¡¥Sand¡¦ (40%) were recorded. At low tidal
level, the main substratum type was ¡¥Gravels and Boulders¡¦ (70%).
¡P
In ST, ¡¥Gravels and Boulders¡¦ was the main substratum type
(H:90%; M:70%) at high tidal level and mid tidal level. At low tidal level,
¡¥Gravels and Boulders¡¦ was the main substratum type (40%) following by ¡¥Sand
¡¥(30%) and ¡¥Soft Mud¡¥(30%).
3.6.52 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.
Soft shore communities
3.6.53 Table 3.4 of Appendix O lists the total abundance, density and number of taxon
of every phylum in this survey. A total of 15339 individuals were recorded.
Mollusca was the most abundant phylum (total abundance14170 ind,
density 472 ind. m-2, relative abundance 92.4%). The second and
third abundant phya were Arthropoda (1008 ind., 34
ind. m-2, 606%) and Annelida (60 ind., 2 ind. m-2, 0.4%)
respectively. Relatively other phyla were very low in abundances (density <2
ind. m-2, relative abundance 0.3%). Moreover, the most diverse
phylum was Mollusca (44taxa) followed by Annelida (8 taxa) and Arthropoda (7
taxa). There were 2 taxa recorded for Cnidaria and 1 taxon for other phyla.
3.6.54 The taxonomic resolution and complete list of recorded fauna are
shown in Annexes IV and V of Appendix O respectively. As reported in June 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
Moreover, taxonomic
revision was conducted on another snail species while the specie name was
revised.:
¡P
Batillaria bornii was revised as Clypeomorus bifasciata
3.6.55 Table 3.5 of Appendix O shows the number of individual, relative abundance and density of each
phylum in every sampling zone. The total abundance (3268 - 4084 ind.) varied
among the four sampling zones while the phyla distributions were similar. In
general, Mollusca was the most dominant phylum (no. of individuals: 3128 - 3895
ind.; relative abundance 85.8 ¡V 95.7 %; density 417 - 519 ind. m-2).
Other phyla were much lower in number of individuals. Arthropoda (106 - 524 ind.;3.2 ¡V 13.0%;
14 - 70 ind. m-2) and Annelida (9 ¡V 19 ind.; 0.3 ¡V 0.5%; 1 - 3 ind.
m-2) were common phyla relatively. Other phyla were very low in
abundance in all sampling zones.
Dominant species in every
sampling zone
3.6.56
Table 3.6 of Appendix O 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 (42-100 ind. m-2). Few listed species
of high or very high density (>100 ind. m-2) were regarded as
dominant species. Other listed species of lower density (<42 ind. m-2)
were regarded as common species.
3.6.57
In TC1, the substratum was mainly ¡¥Gravels and Boulders¡¦ at high and mid
tidal levels. At high tidal level, the gastropod Batillaria zonalis (mean density 57 ind. m-2;
relative abundance 21%) and Monodonta labio (52 ind. m-2; relative abundance 19%) were
of abundant species found at low-moderate densities. Meanwhile, the gastropod Batillaria multiformis
was commonly found at high tidal level with low density (32 ind. m-2)
and relative abundance (12%). At mid tidal level, the Rock oyster Saccostrea cucullate (153 ind. m-2,
22%) was of dominant species with high density. Meanwhile, the gastropod Monodonta labio (96
ind. m-2, 14%) and Batillaria multiformis (78 ind. m-2, 11%) were found at
moderate densities. At low tidal level (main substratum types ¡¥Gravels and
Boulders¡¦ or ¡¥Soft mud¡¦), gastropod Monodonta labio (111 ind. m-2, 96%) was dominant at
high density and followed by the Rock oyster Saccostrea cucullate (96 ind. m-2, 01 %) was abundant at
moderate density.
3.6.58
In TC2, the substratum types were mainly ' Gravels and Boulders'at hightidal level.
Gastropods Monodonta labio (77
ind. m-2, 23 %), Batillaria multiformis (55 ind. m-2, 17 %) and Batillaria zonalis (34
ind. m-2, 10 %), as well as the Rock Oyster Saccostrea cucullata (55 ind. m-2,
17 %) were of abundant species at low - moderate densities. At mid tidal level
(major substratum type ¡¥Gravels and Boulders¡¦), Rock oyster Saccostrea cucullata
was of dominant species at high density. Meanwhile, GastropodsBatillaria zonalis (54ind. m-2, 13 %), Monodonta labio (54
ind. m-2, 12%) and Batillaria multiformis (48 ind. m-2, 11%) were of
abundant species at low- moderate density. Substratum types ¡¥Gravels and
Boulders; and ¡¥Soft mud¡¦ were evenly distributed at low tidal level, Gastropod Monodonta labio (102
ind. m-2, 19%) and the Rock Oyster Saccostrea cucullate (101 ind. m-2, 19%) were of
dominant species at high densities.
3.6.59 In TC3, the substratum types were mainly ¡¥Gravels
and Boulders¡¦ at high tidal level. The Rock oyster Saccostrea cucullate (82
ind. m-2, 17%), gastropod Monodonta
labio(71 ind. m-2, 15%) and Batillaria multiformis (53
ind. m-2, 11%)were of abundant species at low ¡V moderate densities.
At mid tidal level, the substratum types ¡¥Gravels and Boulders¡¦ and ¡¥Sand¡¦ were
evenly distributed. The Rock oyster Saccostrea cucullate (63ind.m-2,
16%) was of abundant species, and followed by Ark clam Barbatia
virescens (46 ind. m-2, 11%) and
gastropod Lunella granulate (42 ind. m-2,
10%). Both of them were at low - moderate densities. At low tidal level, the
major substratum type was ¡¥Gravels and Boulders¡¦. There was dominated by Rock
Oyster Saccostrea cucullate (137 ind. m-2, 20%) and followed
by two abundant species, Barbatia virescens (71 ind. m-2, 10%) and Lunella granulate (71 ind. m-2,
10%), at low - moderate densities.
3.6.60 In ST, the major substratum type
was ¡¥Gravels and Boulders¡¦at high tidal level. At
high tidal level, Gastropod Monodonta labio (79 ind. m-2, 32%) and the Rock Oyster
Saccostrea cucullate (47 ind. m-2,
19%) were abundant at low ¡V moderate densities. At mid tidal level, the main
substratum type was ¡¥Gravals and Boulders¡¦. The Rock
oyster Saccostrea cucullate (122 ind.
m-2, 19%) was dominant at high density and followed by gastropods Monodonta labio (92
ind. m-2, 14%) and the Atrate mussel Xenostrobus atratus (70
ind. m-2, 11 %) at low-moderate densities. At low tidal level (major
substratum: ¡¥Gravals and Boulders¡¦), Rock oyster Saccostrea cucullate (151 ind. m-2,
22 %, attached on boulders) was dominant at high density and followed by
gastropod Monodonta labio (97ind.
m-2, 14 %) at moderate density.
3.6.61 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, Rock Oyster Saccostrea cucullate (1658 ind.), gastropods Monodonta labio (1330 ind.), Batillaria multiformis (499 ind.), Batillaria zonalis (277
ind.) were the most common species on gravel and boulders substratum. Rock
oyster Saccostrea cucullate (1166
ind.), Monodonta labio (860
ind.), Batillaria multiformis
(271 ind.) were the most common species on sandy substrata.
Biodiversity
and abundance of soft shore communities
3.6.62 Table 3.7 of Appendix O shows
the mean values of species number, density, biodiversity index H¡¦ and species evenness J of
soft shore communities at every tidal level and in every sampling zone. As
mentioned above, the differences among sampling zones and tidal levels were
determined by the major type of substratum primarily.
3.6.63 Among the sampling zones, the
mean species number was similar (7 ¡V 12 spp. 0.25 m-2) among the
four sampling zones. The mean densities of TC1 and TC3 (545 and 565 ind. m-2)
were higher than ST (527 ind. m-2) followed by TC2 (436 ind. m-2).
The higher densities of TC1 and TC3 are due to the relatively high number of
individuals in each quadrat. TC1, TC3 and ST were relatively higher in H¡¦ (1.83) while the latter two was
higher in J (0.83) compare with that
of TC1 (0.80) due to the higher species number and even taxa distribution.
Lower H¡¦ (1.6) was resulted in TC2,
which was due to the lower species number. The value of J at TC2 was 0.8, which
was similar to that of TC1.
3.6.64 In the present survey, no clear
trend of mean species number, mean density, H¡¦
and J observed among the tidal level.
3.6.65 Figures 3.14 to 3.17 of
Appendix O 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 (December) but the mean H' and J fluctuated within a limited range.
3.6.66 From June to December 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 unfavorable change reflecting
environmental stresses. The heat stress and serial cyclone hit were believed
the causes during the wet season of 2017. From March 2018 to June 2019,
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
3.6.67 It was
the 27th survey of the EM&A programme
during the construction period. Based on the results, impacts of the HKLR
project were not detected on intertidal soft shore community. Abnormal
phenomena (e.g. rapid, consistent or non-seasonal decline of fauna densities
and species number) were not recorded.
3.7
Solid and
Liquid Waste Management Status
3.7.1
The Contractor registered with EPD as a Chemical Waste
Producer on 12 July 2012 for the Contract. Sufficient numbers of receptacles
were available for general refuse collection and sorting.
3.7.2
The summary of waste flow table is detailed in Appendix K.
3.7.3
The Contractor was reminded that chemical waste
containers should be properly treated and stored temporarily in designated
chemical waste storage area on site in accordance with the Code of Practice on
the Packaging, Labelling and Storage of Chemical Wastes.
3.8
Environmental
Licenses and Permits
3.8.1
The valid environmental licenses and permits during
the reporting period are summarized in Appendix L.
4
Environmental Complaint and
Non-compliance
4.1.1
The detailed air quality, noise, water quality and dolphin exceedances
are provided in Appendix M. Also, the summaries of
the environmental exceedances are presented as follows:
Air
Quality
4.1.2
No Action Level and Limit level exceedances
of 1-hr TSP and 24-hr TSP were recorded at AMS5 and AMS6 during the reporting period.
Noise
4.1.3 No Action/Limit Level exceedances for noise were recorded during
daytime on normal weekdays of the reporting period.
Water Quality
4.1.4 No Action Level and Limit Level exceedances
of turbidity level and suspended solids level were recorded during the
reporting period. No Action/Limit Level exceedances of dissolved oxygen were recorded at
bottom level during mid-ebb tide. No Limit Level exceedances of dissolved
oxygen were recorded at bottom level during mid-flood tide.
4.1.5 2 Action
Level exceedances of dissolved oxygen at stations IS10(N), SR5(N) and 2 Limit Level
exceedances of dissolved oxygen were recorded at SR10A(N), SR10B(N2) at surface and middle level during mid-ebb tide.
2 Action Level exceedances of dissolved oxygen at stations IS10(N), SR5(N) and
2 Limit Level exceedances of dissolved oxygen were recorded at SR10A(N), SR10B(N2) at surface and middle level during mid-flood
tide. 4 Action Level exceedances of dissolved oxygen were recorded at IS10(N),
SR5(N), SR10A(N) and SR10B(N2) at bottom level during mid-flood tide. The exceedances were considered as non-contract related.
Dolphin
4.1.6 There was a Limit Level exceedance of dolphin monitoring for the
quarterly monitoring data (between June 2019 and August 2019). According to the
contractor¡¦s information, the marine activities undertaken for HKLR03 during
the quarter of June 2019 ¡V August 2019 included seawall construction.
4.1.7 There is no evidence showing the current LL
non-compliance directly related to the construction works of HKLR03 (where the
amounts of working vessels for HKLR03 have been decreasing), although the
generally increased amount of vessel traffic in NEL during the impact phase has
been partly contributed by HKLR03 works since October 2012. It should also be
noted that work area under HKLR03 (adjoining the Airport Island) situates in
waters which has rarely been used by dolphins in the past, and the working
vessels under HKLR03 have been travelling from source to destination in
accordance with the Marine Travel Route to minimize impacts on Chinese White
Dolphin (CWD). In addition, the contractor will implement proactive mitigation
measures such as avoiding anchoring at Marine Department¡¦s designated anchorage
site ¡V Sham Shui Kok Anchorage (near Brothers Island)
as far as practicable.
4.1.8 All
dolphin protective measures are fully and properly implemented in accordance
with the EM&A Manual. According to the Marine Travel Route Plan, the
travelling speed of vessels must not exceed 5 knots when crossing the edge of
the proposed marine park. The Contractor will continue to provide training for
skippers to ensure that their working vessels travel from source to destination
to minimize impacts on Chinese White Dolphin and avoid anchoring at Marine
Department¡¦s designated anchorage site - Sham Shui Kok
Anchorage (near Brothers Island) as far as practicable. Also, it is recommended
to complete the marine works of the Contract as soon as possible so as to
reduce the overall duration of impacts and allow the dolphins population to
recover as early as possible.
4.2.1 There was no complaint received in
relation to the environmental impacts during this reporting period. The details of cumulative statistics of
Environmental Complaints are provided in Appendix N.
4.2.2 No notification of summons and
prosecution was received during the reporting period. Statistics on
notifications of summons and successful prosecutions are summarized in Appendix M.
5
Comments, Recommendations and Conclusion
5.1.1
According to the environmental
site inspections undertaken during the reporting period, the following
recommendations were provided:
¡P
The Contractor was reminded to remove the waste from
N4, S7, S15, S16 and LCSD Depot.
¡P
The Contractor was reminded to remove the waste on the
ground from LCSD Depot, Depressed Roundabout and N4.
¡P
The Contractor was reminded to remove the waste around
the trees from N4.
¡P
The Contractor was reminded to remove the concrete
deposit from N4.
¡P
The Contractor was reminded to remove the construction
waste and general refuse on the ground from LCSD Depot.
¡P
The Contractor was reminded to remove the stagnant
water from the lid of the water-filled barrier at N4.
¡P
The Contractor was reminded to remove the stagnant
water inside the drip tray from S7.
¡P
The Contractor was reminded to remove the stagnant
water on the ground at N4, S7, S15 and LCSD Depot.
¡P
The Contractor was reminded to remove the stagnant
water from S16, N4 and S7.
¡P
The Contractor was reminded to remove the muddy water
near the exit/entrance of S7.
¡P
The Contractor was reminded to provide drip trays for
the chemical containers at S7, N4 and LCSD Depot and the unused chemical
containers at S15 and LCSD Depot.
¡P
The Contractor was reminded to provide proper chemical
labels for chemical containers at S7.
¡P
The Contractor was reminded to remove the oil stain on
the ground properly at LCSD Depot.
5.2.1
The impact monitoring programme for air
quality, noise, water quality and dolphin
ensured that any deterioration in environmental condition was readily detected
and timely actions taken to rectify any non-compliance. Assessment and analysis
of monitoring results collected demonstrated the environmental impacts of the
contract. With implementation of the recommended environmental mitigation
measures, the contract¡¦s environmental impacts were considered environmentally
acceptable. The weekly environmental site inspections and bi-weekly environmental
site inspection of landscape works ensured that all the environmental
mitigation measures recommended were effectively implemented.
5.2.2
The
recommended environmental mitigation measures, as included in the EM&A programme, effectively minimize the potential environmental
impacts from the contract. Also, the EM&A programme
effectively monitored the environmental impacts from the construction
activities and ensure the proper implementation of mitigation measures. No
particular recommendation was advised for the improvement of the programme.
5.3.1 The construction phase and EM&A programme
of the Contract commenced on 17 October 2012. This is the twenty-eighth Quarterly EM&A Report which
summarizes the monitoring results and audit findings of
the EM&A programme during the reporting period
from 1 June 2019 to 31 August 2019.
Air Quality
5.3.2
No Action Level and Limit Level exceedances
of 1-hr TSP and 24-hr TSP were recorded at AMS5 and AMS6 during the reporting period.
Noise
5.3.3
No Action/Limit Level exceedances for noise were recorded during daytime
on normal weekdays of the reporting period.
Water Quality
5.3.5
2 Action Level exceedances of dissolved oxygen at
stations IS10(N), SR5(N) and 2 Limit Level exceedances of dissolved oxygen were
recorded at SR10A(N), SR10B(N2) at surface
and middle level during mid-ebb tide. 2 Action Level exceedances of dissolved
oxygen at stations IS10(N), SR5(N) and 2 Limit Level exceedances of dissolved
oxygen were recorded at SR10A(N), SR10B(N2) at surface
and middle level during mid-flood tide. 4 Action Level exceedances of dissolved
oxygen were recorded at IS10(N), SR5(N), SR10A(N) and SR10B(N2) at bottom level
during mid-flood tide. The exceedances were considered
as non-contract related.
Dolphin
5.3.6
There was a Limit Level exceedance of dolphin monitoring for the
quarterly monitoring data between June 2019 and August 2019.
5.3.7
During the present quarter of
dolphin monitoring, no adverse impact from the activities of this construction
project on Chinese White Dolphins was noticeable from general observations.
5.3.8
Although dolphins rarely
occurred in the area of HKLR03 construction in the past and during the baseline
monitoring period, it is apparent that dolphin usage has been dramatically
reduced in NEL since 2012, and many individuals have shifted away completely
from the important habitat around the Brothers Islands.
5.3.9
It is critical to continuously
monitor the dolphin usage in North Lantau region to determine whether the
dolphins are continuously affected by the construction activities in relation
to the HZMB-related works, and whether suitable mitigation measure can be
applied to revert the situation
Mudflat - Sedimentation Rate
5.3.10
This measurement result was generally and relatively higher than the
baseline measurement at S1, S2, S3 and S4. The mudflat level is continuously
increased.
Mudflat - Ecology
5.3.11 The June 2019 survey results
indicate that the impacts of the HKLR project could not be detected on
intertidal soft shore community. Based on the monitoring results, no detectable impact on horseshoe crab
was revealed due to HKLR project. The population change was mainly determined
by seasonal variation, no abnormal phenomenon of horseshoe crab individual,
such as large number of dead individuals on the shore) had been reported. Throughout the monitoring period, the
disappearance of seagrass beds was believed the cause of cyclone hits rather
than impact of HKLR project. The seagrass bed is recolonizing since there has
been a gradual increase in the size and number of that after the hit of the
super cyclone in September 2018.
Environmental Site Inspection and Audit
5.3.12 Environmental site inspection was carried out
on 5, 12, 19 and 28 June 2019; 3, 10, 17 and 26 July 2019; and 1, 7, 14, 21 and 30 August 2019.
Recommendations on remedial actions were given to the Contractors for the
deficiencies identified during the site inspections.
5.3.13
There was no complaint received
in relation to the environmental impact during the reporting period. No notification of summons
and prosecution was received during the reporting period.
5.3.14 No notification of summons and prosecution was received during the
reporting period.