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. 12 (Jun 2015 to Aug 2015)
7
December 2015
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
ˇ§Designated Projectsˇ¨, under Schedule 2 of the Environmental Impact Assessment
(EIA) Ordinance (Cap 499) and EIA Reports (Register No. AEIAR-144/2009 and
AEIAR-145/2009) were prepared for the Project. The current Environmental Permit (EP)
EP-352/2009/D for HKLR and EP-353/2009/I for HKBCF were issued on 22 December 2014
and 17 July 2015, respectively. These documents are available through the EIA
Ordinance Register. The construction phase of
Contract was commenced on 17 October 2012.
BMT
Asia Pacific Limited has been appointed by the Contractor to implement the
Environmental Monitoring & Audit (EM&A) programme for the Contract in
accordance with the Updated EM&A Manual for HKLR (Version 1.0) and will be
providing environmental team services to the Contract.
This
is the twelfth 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 2015 to 31
August 2015.
Environmental
Monitoring and Audit Progress
The EM&A programme were undertaken in
accordance with the Updated EM&A Manual for HKLR (Version 1.0). A summary of the monitoring activities
during this reporting period is presented as below:
Monitoring Activity
|
Monitoring
Date
|
June 2015
|
July 2015
|
August 2015
|
Air
Quality
|
1-hr
TSP
|
2, 8, 12, 18, 24 and 29
|
3, 9, 15, 21, 27 and 31
|
6, 11, 17, 21 and 27
|
24-hr
TSP
|
1, 5, 11, 17, 23 and 26
|
2, 8, 14, 20, 24 and 30
|
AMS5: 5, 11, 14, 20, and 26
AMS6:
5, 10, 14, 20, and 26
|
Noise
|
2, 8, 18, 24 and 29
|
9, 15, 24 and 27
|
6, 11, 17 and 27
|
Water
Quality
|
1, 3, 5, 8, 10, 12, 15, 17, 19, 22, 24,
26 and 29
|
1, 3, 6, 8, 10, 13, 15, 17, 20, 22, 24,
27, 29 and 31
|
3, 5, 7, 10, 12, 14, 17, 19, 21, 24, 26,
28 and 31
|
Chinese
White Dolphin
|
2, 10, 24 and
26
|
2, 7, 22 and
27
|
10, 14, 19
and 28
|
Mudflat Monitoring (Ecology)
|
6, 14,15, 16,
17 and 20
|
-
|
-
|
Mudflat Monitoring (Sedimentation rate)
|
14
|
-
|
-
|
Site Inspection
|
3,
10, 17 and 26
|
2,
8, 16, 22 and 31
|
5,
12, 19 and 28
|
Due to the change of tide pattern and weather
condition, mudflat monitoring (ecology) was rescheduled from 13 June 2015 to 15
June 2015 and from 21 June 2015 to 17 June 2015.
Due to the boat availability issue, the dolphins
monitoring was rescheduled from 16 June 2015 to 24 June 2015, from 23 June 2015
to 26 June 2015, from 24 July 2015 to 22 July 2015, from 29 July 2015 to 27
July 2015, from 18 August 2015 to 19 August 2015 and from 25 August 2015 to 28
August 2015.
Due to weather condition, dolphins monitoring was
rescheduled from 8 July 2015 to 7 July 2015.
As Strong Wind Signal No.3 was hoisted by Hong Kong
Observatory in the morning of 10 July 2015, water quality monitoring for
mid-ebb tide on 10 July 2015 was cancelled for safety reason.
Due to bad weather condition on 21 July 2015, noise
monitoring NMS5 was rescheduled from 21 July 2015 to 24 July 2015.
Due to a power interruption of HVS at station AMS5
on 10 August 2015, the 24-hr TSP monitoring at station AMS5 was rescheduled
from 10 August 2015 to 11 August 2015.
Breaches of Action and Limit Levels
A
summary of environmental exceedances for this reporting period is as follows:
Environmental Monitoring
|
Parameters
|
Action Level (AL)
|
Limit Level (LL)
|
Air
Quality
|
1-hr
TSP
|
0
|
0
|
24-hr
TSP
|
1
|
0
|
Noise
|
Leq
(30 min)
|
0
|
0
|
Water
Quality
|
Suspended
solids level (SS)
|
1
|
0
|
Turbidity
level
|
0
|
0
|
Dissolved
oxygen level (DO)
|
0
|
0
|
Dolphin
Monitoring
|
Quarterly
Analysis (Jun to Aug 2015)
|
0
|
1
|
The
Environmental Team investigated all exceedances and found that they were not
project related.
All
investigation reports for exceedances of the Contract have been submitted to
ENPO/IEC for comments and/or follow up to identify whether the exceedances
occurred related to other HZMB contracts.
Implementation of Mitigation Measures
Site
inspections were carried out on a weekly basis to monitor the implementation of
proper environmental pollution control and mitigation measures for the Project.
Potential environmental impacts due
to the construction activities were monitored and reviewed.
Complaint Log
There were two environmental complaints
received in relation to the environmental impact during the reporting period.
A
summary of environmental complaints for this reporting period is as follows:
Environmental Complaint No.
|
Date of Complaint Received
|
Description of Environmental
Complaints
|
COM-2015-074
|
16
July 2015
|
Wastewater splashing from vehicles
|
COM-2015-076
|
17
July 2015
|
Noise
|
Notifications of Summons and Prosecutions
There
were no notifications of summons or prosecutions received during this reporting
period.
Reporting Changes
This
report has been developed in compliance with the reporting requirements for the
quarterly summary EM&A reports as required by the Updated EM&A Manual
for HKLR (Version 1.0).
The proposal
for the change of Action Level and Limit Level for suspended solid and
turbidity was approved by EPD on 25 March 2013.
The
revised Event and Action Plan for dolphin monitoring
was approved by EPD on 6 May 2013.
The
original monitoring station at IS(Mf)9 (Coordinate- East:813273, North 818850)
was observed inside the perimeter silt curtain of Contract HY/2010/02 on 1 July
2013, as such the original impact water quality monitoring location at IS(Mf)9
was temporarily shifted outside the silt curtain. As advised by the Contractor of HY/2010/02 in
August 2013, the perimeter silt curtain was shifted to facilitate safe
anchorage zone of construction barges/vessels until end of 2013 subject to
construction progress. Therefore,
water quality monitoring station IS(Mf)9 was shifted to 813226E and 818708N
since 1 July 2013. According to the
water quality monitoring teamˇ¦s observation on 24 March 2014, the original
monitoring location of IS(Mf)9 was no longer enclosed by the perimeter silt
curtain of Contract HY/2010/02.
Thus, the impact water quality monitoring works at the original
monitoring location of IS(Mf)9 has been resumed since 24 March 2014.
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.
1.1.2
The HKLR project has been
separated into two contracts. They are Contract
No. HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section
between Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter
referred to as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao
Bridge Hong Kong Link Road-Section between HKSAR Boundary and Scenic Hill.
1.1.3
China State Construction
Engineering (Hong Kong) Ltd. was awarded by Highways Department (HyD) as the
Contractor to undertake the construction works of Contract No. HY/2011/03. The Contract is part of the HKLR
Project and HKBCF Project, these projects are considered to be ˇ§Designated
Projectsˇ¨, under Schedule 2 of the Environmental Impact Assessment (EIA)
Ordinance (Cap 499) and EIA Reports (Register No. AEIAR-144/2009 and
AEIAR-145/2009) were prepared for the Project. The current Environmental Permit (EP) EP-352/2009/D
for HKLR and EP-353/2009/I for HKBCF were issued on 22 December 2014 and 17 July
2015, respectively. These documents are available through the EIA Ordinance
Register. The construction phase of Contract was commenced on 17 October 2012. Figure 1.1 shows the project site boundary.
1.1.5
This is the twelfth 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 2015 to 31 August 2015.
1.2.1 The project organization structure and lines of
communication with respect to the on-site environmental management structure
with the key personnel contact names and numbers are shown in Appendix A.
1.3
Construction Programme
1.3.1 A
copy of the Contractorˇ¦s construction programme is provided in Appendix B.
1.4
Construction
Works Undertaken During the Reporting Period
1.4.1 A
summary of the construction activities undertaken during this reporting period
is shown in Table 1.1.
The Works areas of the Contract are showed in Appendix
C.
Table 1.1 Construction
Activities during Reporting Period
Site Area
|
Description
of Activities
|
Portion X
|
Dismantling/trimming of temporary 40mm stone
platform for construction of seawall
|
Portion X
|
Filling works behind stone platform
|
Portion X
|
Construction of seawall
|
Portion X
|
Loading and unloading of filling materials
|
Portion X
|
Temporary
stone platform construction
|
Portion X
|
Band
drains installation
|
Portion X
|
Excavation
and lateral support works for Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Socket
H-Piling work for Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Laying blinding layer for tunnel box structure at
Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Construction of Sheet Pile
at Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Construction
of tunnel box structure at Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Pipe piling works for HKBCF to Airport Tunnel East
(Cut & Cover Tunnel)
|
Portion X
|
Excavation for HKBCF to Airport Tunnel
|
West Portal
|
Excavation for Scenic Hill Tunnel
|
West Portal
|
Ventilation building
foundation and superstructure works
|
Airport Road
|
Works
for diversion of Airport Road
|
Airport Road/ Airport Express Line/ East Coast Road
|
Utilities detection
|
Airport Road/ Airport Express Line/ East Coast Road
|
Establishment of Site Access
|
Airport Express Line
|
Canopy pipe drilling underneath Airport Express Line
|
Kwo Lo Wan Road
|
Excavation
and lateral support works at shaft 3 extension north shaft & south shaft
|
Airport Road
|
Excavation and Lateral
Support Works for HKBCF to Airport Tunnel West (Cut & Cover Tunnel)
|
Portion Y
|
Utility culvert excavation
|
Portion Y
|
Highway Operation and Maintenance Area
Building Foundation Works
|
2.1
Summary of EM&A Requirements
2.1.1
The EM&A programme requires environmental
monitoring of air quality, noise, water quality, dolphin monitoring and mudflat
monitoring as specified in the approved EM&A Manual.
2.1.2 A summary of Impact
EM&A requirements is presented in Table
2.1. The
locations of air quality, noise and water quality monitoring stations are shown
as in Figure 2.1. The transect line layout in Northwest
and Northeast Lantau Survey Areas is presented in Figure 2.2.
Table 2.1 Summary
of Impact EM&A Requirements
Environmental
Monitoring
|
Description
|
Monitoring
Station
|
Frequencies
|
Remarks
|
Air Quality
|
1-hr TSP
|
AMS 5 & AMS 6
|
At least 3 times every 6 days
|
While the
highest dust impact was expected.
|
24-hr TSP
|
At least once every 6 days
|
--
|
Noise
|
Leq (30mins),
L10 (30mins) and
L90 (30mins)
|
NMS5
|
At least once per week
|
Daytime on normal weekdays
(0700-1900 hrs).
|
Water Quality
|
ˇP Depth
ˇP Temperature
ˇP Salinity
ˇP Dissolved
Oxygen (DO)
ˇP Suspended
Solids (SS)
ˇP DO
Saturation
ˇP Turbidity
ˇP pH
|
ˇP Impact
Stations:
IS5, IS(Mf)6, IS7, IS8, IS(Mf)9 & IS10,
ˇP Control/Far
Field Stations:
CS2 & CS(Mf)5,
ˇP Sensitive
Receiver Stations:
SR3, SR4, SR5, SR10A & SR10B
|
Three times per week
during mid-ebb and mid-flood tides (within ˇÓ 1.75 hour of the predicted time)
|
3
(1 m below water surface,
mid-depth and 1 m above sea bed, except where the water depth is less than 6
m, in which case the mid-depth station may be omitted. Should the water depth be less than 3
m, only the mid-depth station will be monitored).
|
Dolphin
|
Line-transect Methods
|
Northeast Lantau survey
area and Northwest Lantau survey area
|
Twice
per month
|
--
|
Mudflat
|
Horseshoe crabs, seagrass beds, intertidal soft shore communities,
sedimentation rates and water quality
|
San Tau and Tung Chung Bay
|
Once every 3 months
|
--
|
2.2.1 Table 2.2 presents the Action and Limit Levels for the
1-hour TSP, 24-hour TSP and noise level.
Table 2.2 Action
and Limit Levels for 1-hour TSP, 24-hour
TSP and Noise
Environmental Monitoring
|
Parameters
|
Monitoring Station
|
Action Level
|
Limit Level
|
Air
Quality
|
1-hr
TSP
|
AMS
5
|
352 µg/m3
|
500 µg/m3
|
AMS
6
|
360 µg/m3
|
24-hr
TSP
|
AMS
5
|
164 µg/m3
|
260 µg/m3
|
AMS
6
|
173 µg/m3
|
Noise
|
Leq
(30 min)
|
NMS 5
|
When
one documented complaint is received
|
75
dB(A)
|
2.2.2 The Action and Limit Levels for water quality monitoring are given as in
Table 2.3.
Table 2.3 Action
and Limit Levels for Water Quality
Parameter
(unit)
|
Water Depth
|
Action Level
|
Limit Level
|
Dissolved Oxygen (mg/L)
|
Surface and Middle
|
5.0
|
4.2 except 5 for Fish
Culture Zone
|
Bottom
|
4.7
|
3.6
|
Turbidity (NTU)
|
Depth average
|
27.5 or 120% of upstream
control stationˇ¦s turbidity at the same tide of the same day;
The action level has been
amended to ˇ§27.5 and 120% of upstream control stationˇ¦s turbidity at the same
tide of the same dayˇ¨ since 25 March 2013.
|
47.0 or 130% of turbidity
at the upstream control station at the same tide of same day;
The limit level has been
amended to ˇ§47.0 and 130% of turbidity at the upstream control station at the
same tide of same dayˇ¨ since 25 March 2013.
|
Suspended Solid (SS)
(mg/L)
|
Depth average
|
23.5 or 120% of upstream
control stationˇ¦s SS at the same tide of the same day;
The action level has been
amended to ˇ§23.5 and 120% of upstream control stationˇ¦s SS at the same tide of
the same dayˇ¨ since 25 March 2013.
|
34.4 or 130% of SS at the
upstream control station at the same tide of same day and 10mg/L for Water
Services Department Seawater Intakes;
The limit level has been
amended to ˇ§34.4 and 130% of SS at the upstream control station at the same
tide of same day and 10mg/L for Water Services Department Seawater Intakesˇ¨
since 25 March 2013
|
Notes:
(1) Depth-averaged
is calculated by taking the arithmetic means of reading of all three depths.
(2) For DO,
non-compliance of the water quality limit occurs when monitoring result is
lower that the limit.
(3) For SS
& turbidity non-compliance of the water quality limits occur when
monitoring result is higher than the limits.
(4) The change
to the Action and limit Levels for Water Quality Monitoring for the EM&A
works was approved by EPD on 25 March 2013. Therefore, the amended Action and Limit
Levels are applied for the water monitoring results obtained on and after 25
March 2013.
2.2.3 The Action and Limit Levels for dolphin monitoring are shown in Tables 2.4 and 2.5.
Table 2.4 Action
and Limit Level for Dolphin Impact Monitoring
|
North Lantau
Social Cluster
|
NEL
|
NWL
|
Action Level
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
Limit Level
|
STG < 40% of baseline
&
ANI < 40% of baseline
|
Remarks:
(1)
STG means quarterly average encounter rate of
number of dolphin sightings.
(2)
ANI means quarterly average encounter rate of
total number of dolphins.
(3)
For North Lantau Social Cluster, AL will be
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
site audit findings, the Contractor have rectified most of the observations as
identified during environmental site inspection during the reporting period.
Follow-up actions for outstanding observations will be inspected during the
next reporting period. Details of site audit findings and the corrective
actions during the reporting period are presented in Appendix F.
3.1.2 A summary of the
Implementation Schedule of Environmental Mitigation Measures (EMIS) is
presented in Appendix E.
3.1.3 Regular marine travel route for marine vessels were implemented
properly in accordance to the submitted plan and relevant records were kept
properly.
3.1.4 Dolphin Watching Plan was implemented during the reporting period. No dolphins inside the silt curtain
were observed. The relevant records were kept properly.
3.2.1 The monitoring
results for 1-hour TSP and 24-hour TSP are summarized in Tables 3.1 and 3.2 respectively. Detailed impact air quality monitoring
results and relevant graphical plots are
presented in Appendix G.
Table 3.1 Summary
of 1-hour TSP Monitoring Results During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
June 2015
|
AMS5
|
66
|
55 - 92
|
352
|
500
|
AMS6
|
65
|
55 - 76
|
360
|
July 2015
|
AMS5
|
77
|
48 - 123
|
352
|
AMS6
|
76
|
58 - 95
|
360
|
August 2015
|
AMS5
|
89
|
60 ˇV 190
|
352
|
AMS6
|
82
|
60 - 134
|
360
|
Table 3.2 Summary
of 24-hour TSP Monitoring Results During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
June 2015
|
AMS5
|
18
|
13 - 23
|
164
|
260
|
AMS6
|
37
|
26 - 46
|
173
|
July 2015
|
AMS5
|
28
|
14 - 55
|
164
|
AMS6
|
79
|
27 - 238
|
173
|
August 2015
|
AMS5
|
31
|
20 - 65
|
164
|
AMS6
|
55
|
34 - 96
|
173
|
3.2.2 No Action and Limit Level exceedances of 1-hour TSP
and 24-hour TSP were recorded at AMS5 during the reporting month.
3.2.3 No Action and Limit Level exceedances of 1-hour TSP
were recorded at AMS6 during the reporting month. No Limit Level exceedances of 24-hour TSP were recorded at AMS6 during the
reporting month.
3.2.4
An Action Level exceedance of 24-hr TSP level was recorded at AMS6
during the reporting month. Record of ˇ§Notification of Environmental Quality
Limit Exceedancesˇ¨ is provided in Appendix M.
3.3
Noise Monitoring
Results
3.3.1
The monitoring results for construction noise are
summarized in Table 3.3 and the monitoring
results and relevant graphical plots for this reporting period are provided in Appendix H.
Table 3.3 Summary
of Construction Noise Monitoring Results During the Reporting Period
Reporting period
|
Monitoring Station
|
Average Leq (30 mins),
dB(A)*
|
Range of Leq (30
mins), dB(A)*
|
Action Level
|
Limit Level Leq (30
mins), dB(A)
|
June 2015
|
NMS5
|
68
|
64 ˇV 70
|
When one documented complaint is received
|
75
|
July 2015
|
60
|
56 ˇV 65
|
August 2015
|
57
|
56 ˇV 58
|
3.3.2
There were no Action and Limit Level exceedances for noise during
daytime on normal weekdays of the reporting
period.
3.3.3 Major noise sources
during the noise monitoring included construction activities of the Contract
and nearby traffic noise and insect noise.
3.4.1 Impact water quality
monitoring was conducted at all designated monitoring stations during the
reporting period. Impact water
quality monitoring results and relevant graphical plots are provided in Appendix I.
3.4.2 During the reporting
period, one
Action Level exceedance for
suspended solid level were recorded. Record of ˇ§Notification of Environmental Quality Limit Exceedancesˇ¨ is
provided in Appendix M. No exceedance of Limit Level for suspended
solid level was recorded. No exceedances
of Action and Limit
Level for
dissolved oxygen level and turbidity
were recorded.
3.4.3 Water quality impact
sources during the water quality monitoring were the construction activities of
the Contract, nearby construction activities by other parties and nearby
operating vessels by other parties.
Data Analysis
3.5.1 Distribution Analysis ˇV The line-transect survey data was integrated
with the Geographic Information System (GIS) in order to visualize and
interpret different spatial and temporal patterns of dolphin distribution using
sighting positions. Location data of
dolphin groups were plotted on map layers of Hong Kong using a desktop GIS
(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 ˇV Encounter rates of Chinese White Dolphins
(number of on-effort sightings per 100 km of survey effort, and total number of
dolphins sighted on-effort per 100 km of survey effort) were calculated in NEL
and NWL survey areas in relation to the amount of survey effort conducted
during each month of monitoring survey. Dolphin encounter rates were calculated
in two ways for comparisons with the HZMB baseline monitoring results as well
as to AFCD long-term marine mammal monitoring results.
3.5.3 Firstly, for the comparison with the HZMB baseline monitoring
results, the encounter rates were calculated using primary survey effort alone,
and only data collected under Beaufort 3 or below condition would be used for
encounter rate analysis. The
average encounter rate of sightings (STG) and average encounter rate of
dolphins (ANI) were deduced based on the encounter rates from six events during
the present quarter (i.e. six sets of line-transect surveys in North Lantau),
which was also compared with the one deduced from the six events during the
baseline period (i.e. six sets of line-transect surveys in North Lantau).
3.5.4 Secondly, the encounter rates were calculated using both primary and
secondary survey effort collected under Beaufort 3 or below condition as in
AFCD long-term monitoring study.
The encounter rate of sightings and dolphins were deduced by dividing
the total number of on-effort sightings and total number of dolphins (ANI) by
the amount of survey effort for the entire quarterly period (July ˇV August 2015).
3.5.5 Quantitative grid analysis on habitat use ˇV To conduct quantitative
grid analysis of habitat use, positions of on-effort sightings of Chinese White
Dolphins collected during the quarterly impact phase monitoring period were
plotted onto 1-km2 grids among Northwest Lantau (NWL) and Northeast
(NEL) survey areas on GIS. Sighting
densities (number of on-effort sightings per km2) and dolphin
densities (total number of dolphins from on-effort sightings per km2)
were then calculated for each 1 km by 1 km grid with the aid of GIS. Sighting density grids and dolphin
density grids were then further normalized with the amount of survey effort
conducted within each grid. The
total amount of survey effort spent on each grid was calculated by examining
the survey coverage on each line-transect survey to determine how many times
the grid was surveyed during the study period. For example, when the survey boat
traversed through a specific grid 50 times, 50 units of survey effort were
counted for that grid. With the
amount of survey effort calculated for each grid, the sighting density and
dolphin density of each grid were then normalized (i.e. divided by the unit of
survey effort).
3.5.6 The newly-derived unit for sighting density was termed SPSE,
representing the number of on-effort sightings per 100 units of survey
effort. In addition, the derived
unit for actual dolphin density was termed DPSE, representing the number of
dolphins per 100 units of survey effort.
Among the 1-km2 grids that were partially covered by land,
the percentage of sea area was calculated using GIS tools, and their SPSE and
DPSE values were adjusted accordingly.
The following formulae were used to estimate SPSE and DPSE in each 1-km2
grid within the study area:
SPSE = ((S / E) x 100) / SA%
DPSE = ((D / E) x 100) / SA%
where S
= total number of on-effort sightings
D = total number of dolphins from on-effort sightings
E = total number of units of survey effort
SA% = percentage of sea area
3.5.7 Behavioural analysis ˇV When dolphins were sighted during vessel
surveys, their behaviour was observed.
Different activities were categorized (i.e. feeding, milling/resting,
traveling, socializing) and recorded on sighting datasheets. This data was then input into a separate
database with sighting information, which can be used to determine the
distribution of behavioural data with a desktop GIS. Distribution of sightings of dolphins
engaged in different activities and behaviours would then be plotted on GIS and
carefully examined to identify important areas for different activities of the
dolphins.
3.5.8 Ranging pattern analysis ˇV Location data of individual dolphins that
occurred during the 3-month baseline monitoring period were obtained from the
dolphin sighting database and photo-identification catalogue. To deduce home ranges for individual
dolphins using the fixed kernel methods, the program Animal Movement Analyst
Extension, was loaded as an extension with 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 2015, six sets of systematic line-transect vessel
surveys were conducted to cover all transect lines in NWL and NEL survey areas
twice per month.
3.5.10
From these surveys, a total of 900.64 km
of survey effort was collected, with 92.8% of the total survey effort being
conducted under favourable weather conditions (i.e. Beaufort Sea State 3 or
below with good visibility). Among
the two areas, 345.58 km and 555.06 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 655.74 km, while the effort on secondary lines was 244.90
km. Survey effort conducted on both
primary and secondary lines were considered as on-effort survey data. A summary table of the survey effort is
shown in Annex I of Appendix
J.
3.5.12
During the six sets of monitoring surveys
in June to August 2015, a total of 12 groups of 42 Chinese White Dolphins were
sighted. All dolphin sightings were
made during on-effort search, and all of them were made on primary lines. In
this quarterly period, all except one dolphin groups were sighted in NWL, while
only one group of a lone animal was sighted in NEL. Notably, this was the first dolphin
sighted in NEL since July 2014 during HKLR03 monitoring surveys. A summary table of the dolphin sightings is shown
in Annex II of Appendix
J.
Distribution
3.5.13
Distribution of dolphin
sightings made during monitoring surveys in June to August 2015 is shown in
Figure 1 of Appendix J. Dolphin sightings made in the present
quarter were only clustered to the north and northeast of Lung Kwu Chau, and to
the southwestern end of NWL survey area near the HKLR09 alignment (Figure 1 of Appendix J). The lone dolphin sighted in NEL was
located between Shum Shui Kok and Yam O, while there was another group of two
dolphins sighted to the west of Sha Chau during this quarter (Figure 1 of Appendix J).
3.5.14
Notably, all dolphin sightings
were made far away from the HKLR03/HKBCF reclamation sites as well as along the
entire alignment of Tuen Mun-Chek Lap Kok Link (TMCLKL) during the present
quarterly period (Figure
1 of Appendix J). However, three sightings (with two lone
individuals in two sightings and another group of four dolphins) were made in
the vicinity of the HKLR09 alignment (Figure 1 of Appendix J).
3.5.15
Sighting distribution of the
present impact phase monitoring period (June to August 2015) was compared to
the one during the baseline monitoring period (September to November
2011). In the present quarter, dolphins
have almost vacated the NEL region, which was in stark contrast to their
frequent occurrence 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 ten quarters
of HKLR03 monitoring, which has resulted in extremely low to zero dolphin
encounter rate in this area.
3.5.16
In NWL survey area, dolphin occurrence was
also drastically different between the baseline and impact phase periods. During the present impact monitoring
period, much fewer dolphins occurred in this survey area than during the
baseline period, when many of the dolphin sightings were concentrated between
Lung Kwu Chau and Black Point, around Sha Chau, near Pillar Point and to the
west of the Chek Lap Kok Airport (Figure
1 of Appendix
J).
3.5.17
Another comparison in dolphin
distribution was made between the three quarterly periods of summer months in
2013, 2014 and 2015 (Figure 2 of Appendix J). Among the three summer periods, only one
dolphin sighting was made in NEL in both 2014 and 2015, while there were a
number of sightings made there in 2013 (Figure 2 of Appendix J).
3.5.18
Dramatic changes in dolphin
distribution in NWL waters were also observed in the summer months during the
three-year period (Figure 2 of Appendix
J). In 2013, dolphin regularly occurred
throughout the NWL survey area, with higher concentrations of sightings around
Sha Chau, Lung Kwu Chau, near Black Point and Pillar Point, and to the north of
airport platform. In 2014, dolphin
still occurred around Sha Chau and Lung Kwu Chau at a high level, but less
frequently in the middle portion of North Lantau region. In 2015, they infrequently occurred in
NWL survey area with the only concentration around Lung Kwu Chau while they
generally absent throughout this area.
The temporal trend indicated that dolphin usage in the NWL region has
progressively diminished during the summer months in the past few years.
Encounter Rate
3.5.19 During the present three-month study period, the encounter rates of
Chinese White Dolphins deduced from the survey effort and on-effort sighting
data from the primary transect lines under favourable conditions (Beaufort 3 or
below) for each set of the surveys in NEL and NWL are shown in Table
3.4. The average
encounter rates deduced from the six sets of surveys were also compared with
the ones deduced from the baseline monitoring period (September ˇV November
2011) (See Table 3.5).
Table 3.4 Dolphin
Encounter Rates (Sightings Per 100 km of Survey Effort) During Reporting Period
(June to August 2015)
Survey Area
|
Dolphin
Monitoring
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
Primary Lines Only
|
Primary Lines Only
|
Northeast Lantau
|
Set 1 (2 & 10 Jun 2015)
|
0.00
|
0.00
|
Set 2 (24 & 26 Jun 2015)
|
2.64
|
2.64
|
Set 3 (2 & 7 Jul
2015)
|
0.00
|
0.00
|
Set 4 (22 & 27 Jul 2015)
|
0.00
|
0.00
|
Set 5 (10
& 14 Aug
2015)
|
0.00
|
0.00
|
Set 6 (19 & 28 Aug 2015)
|
0.00
|
0.00
|
Northwest Lantau
|
Set 1 (2 & 10 Jun 2015)
|
1.51
|
15.15
|
Set 2 (24 & 26 Jun 2015)
|
0.00
|
0.00
|
Set 3 (2 & 7 Jul
2015)
|
1.69
|
3.38
|
Set 4 (22 & 27 Jul 2015)
|
3.46
|
6.92
|
Set 5 (10
& 14 Aug
2015)
|
0.00
|
0.00
|
Set 6 (19 & 28 Aug 2015)
|
8.53
|
29.84
|
Table
3.5 Comparison of average dolphin encounter rates from impact
monitoring period (June to August 2015) and baseline monitoring period (September
ˇV November 2011)
Survey Area
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
Reporting Period
|
Baseline Monitoring Period
|
Reporting Period
|
Baseline Monitoring Period
|
Northeast Lantau
|
0.44 ˇÓ 1.08
|
6.00 ˇÓ 5.05
|
0.44 ˇÓ 1.08
|
22.19 ˇÓ
26.81
|
Northwest Lantau
|
2.53 ˇÓ 3.20
|
9.85 ˇÓ 5.85
|
9.21 ˇÓ 11.57
|
44.66 ˇÓ
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) ˇÓ
denotes the standard deviation of the average encounter rates.
3.5.20
To facilitate the comparison
with the AFCD long-term monitoring results, the encounter rates were also
calculated for the present quarter using both primary and secondary survey
effort. The encounter rates of sightings
(STG) and dolphins (ANI) in NWL were 2.04 sightings and 7.55
dolphins per 100 km of survey effort respectively, while the encounter rates of
sightings (STG) and dolphins (ANI) in NEL were both 0.29 for this quarter.
3.5.21
In NEL, the average dolphin
encounter rates (both STG and ANI) in the present three-month impact monitoring
period were zero, and such low occurrence of dolphins in NEL have been
consistently recorded in the past nine quarters (Table 3.6). It is a serious
concern that dolphin occurrence in NEL in the last ten quarters (0.0-1.0 for
ER(STG) and 0.0-3.9 for ER(ANI)) have been exceptionally low when compared to
the baseline period (Table 3.6). Dolphins have almost vacated from NEL
waters since January 2014, with only two groups of five dolphins sighted since
then despite consistent and intensive survey effort being conducted in this
area.
3.5.22
Moreover, the average dolphin encounter rates (STG and ANI) in NWL
during the present impact phase monitoring period were also much lower
(reductions of 74.3% and 79.3% respectively) than the ones recorded in the
3-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).
3.5.23
Even for the same summer quarters, the dolphin encounter rates in NWL
during summer 2015 were much lower than the ones recorded in summer 2013 and
2014 (Table 3.7).
Table 3.6 Comparison of Average Dolphin Encounter Rates in Northeast Lantau
Survey Area from All Quarters of Impact Monitoring Period and Baseline
Monitoring Period (Sep ˇV Nov 2011)
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 ˇÓ 5.05
|
22.19 ˇÓ 26.81
|
December 2012-February
2013 (Impact)
|
3.14
ˇÓ 3.21
|
6.33
ˇÓ 8.64
|
March-May
2013 (Impact)
|
0.42
ˇÓ 1.03
|
0.42
ˇÓ 1.03
|
June-August
2013 (Impact)
|
0.88
ˇÓ 1.36
|
3.91
ˇÓ 8.36
|
September-November
2013 (Impact)
|
1.01
ˇÓ 1.59
|
3.77
ˇÓ 6.49
|
December 2013-February
2014 (Impact)
|
0.45
ˇÓ 1.10
|
1.34
ˇÓ 3.29
|
March-May
2014 (Impact)
|
0.00
|
0.00
|
June-August 2014
(Impact)
|
0.42
ˇÓ 1.04
|
1.69
ˇÓ 4.15
|
September-November
2014 (Impact)
|
0.00
|
0.00
|
December
2014-February 2015 (Impact)
|
0.00
|
0.00
|
March-May 2015
(Impact)
|
0.00
|
0.00
|
June ˇV August
2015 (Impact)
|
0.44 ˇÓ
1.08
|
0.44 ˇÓ 1.08
|
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) ˇÓ denotes
the standard deviation of the average encounter rates.
Table 3.7 Comparison of
Average Dolphin Encounter Rates in Northwest Lantau Survey Area from All
Quarters of Impact Monitoring Period and Baseline Monitoring Period (Sep ˇV Nov
2011)
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
ˇÓ 5.85
|
44.66
ˇÓ 29.85
|
December 2012-February
2013 (Impact)
|
8.36
ˇÓ 5.03
|
35.90
ˇÓ 23.10
|
March-May
2013 (Impact)
|
7.75 ˇÓ 3.96
|
24.23
ˇÓ 18.05
|
June-August
2013 (Impact)
|
6.56
ˇÓ 3.68
|
27.00
ˇÓ 18.71
|
September-November
2013 (Impact)
|
8.04
ˇÓ 1.10
|
32.48
ˇÓ 26.51
|
December 2013-February
2014 (Impact)
|
8.21
ˇÓ 2.21
|
32.58
ˇÓ 11.21
|
March-May
2014 (Impact)
|
6.51
ˇÓ 3.34
|
19.14
ˇÓ 7.19
|
June-August
2014 (Impact)
|
4.74 ˇÓ 3.84
|
17.52
ˇÓ 15.12
|
September-November
2014 (Impact)
|
5.10 ˇÓ 4.40
|
20.52 ˇÓ 15.10
|
December 2014-February
2015 (Impact)
|
2.91 ˇÓ 2.69
|
11.27 ˇÓ 15.19
|
March-May
2015 (Impact)
|
0.47 ˇÓ 0.73
|
2.36 ˇÓ 4.07
|
June
ˇV August 2015 (Impact)
|
2.53 ˇÓ 3.20
|
9.21 ˇÓ 11.57
|
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) ˇÓ denotes
the standard deviation of the average encounter rates.
3.5.24
Notably, for the HKLR03 dolphin monitoring programme,
the first eight consecutive quarters have triggered the Action Levels under the
Event and Action Plan, while the past three quarters have all triggered the
Limit Levels. As discussed recently in Hung (2015), the dramatic decline in
dolphin usage of NEL waters in the past few years (including the declines in
abundance, encounter rate and habitat use in NEL, as well as shifts of
individual core areas and ranges away from NEL waters) was possibly related to
the HZMB construction works that were commenced since 2012. It appeared that such noticeable decline
has already extended to NWL waters progressively in 2013 to 2015.
3.5.25 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).
3.5.26
For the comparison between the
baseline period and the present quarter (eleventh
quarter of the impact phase being assessed), the p-values for the differences
in average dolphin encounter rates of STG and ANI were 0.0064 and 0.0270
respectively. If the alpha value is
set at 0.05, significant differences were detected between the baseline and
present quarters in both dolphin encounter rates of STG and ANI.
3.5.27
For the comparison between the baseline period and the
cumulative quarters in impact phase (i.e. first eleven quarters of the impact
phase being assessed), the p-values for the differences in average dolphin
encounter rates of STG and ANI were 0.00020 and 0.00005 respectively. Even if the alpha value is set at 0.01,
significant differences were detected in both the average dolphin encounter
rates of STG and ANI (i.e. between the two periods and the locations).
3.5.28
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, and such low occurrence
of dolphins has also been consistently documented in previous quarters. This raises serious concern, as the
timing of the decline in dolphin usage in North Lantau waters coincided well
with the HZMB-related construction activities (Hung 2015).
3.5.29
To ensure the continuous usage of North Lantau waters
by the dolphins, every possible measure should be implemented by the
contractors and relevant authorities of HZMB-related works to minimize all
disturbances to the dolphins.
Group Size
3.5.30 Group size of
Chinese White Dolphins ranged from one to eight individuals per group in North Lantau region during June
to August 2015. The average dolphin
group sizes from these three months were compared with the ones deduced from
the baseline period in September to November 2011, as shown in Table 3.8.
Table 3.8 Comparison
of Average Dolphin Group Sizes between Reporting Period (June to August 2015)
and Baseline Monitoring Period (SepˇV Nov 2011)
Survey Area
|
Average Dolphin Group Size
|
Reporting Period
|
Baseline Monitoring Period
|
Overall
|
3.50 ˇÓ 2.65 (n
= 12)
|
3.72 ˇÓ 3.13 (n
= 66)
|
Northeast
Lantau
|
1.00 (n = 1)
|
3.18 ˇÓ 2.16 (n
= 17)
|
Northwest
Lantau
|
3.73 ˇÓ 2.65 (n
= 11)
|
3.92 ˇÓ 3.40 (n
= 49)
|
Note:
1) ˇÓ denotes the standard deviation of the average group size.
3.5.31 The average dolphin group sizes
in NWL waters during June to August 2015 were slightly smaller than the ones
recorded during the three-month baseline period (Table 3.8). Half of the
12 groups were composed of 1-3 individuals only, while five other groups were
moderate in size with 4-5 individuals per group. On the other hand, only one large group
of 10 dolphins was sighted during the present quarterly period.
3.5.32
Distribution of dolphins with larger group sizes (five individuals or
more per group) during the present quarter is shown in Figure 3 of Appendix J, with comparison to the
one in baseline period. During the
summer of 2015, distribution of the three groups with five animals and one
group with ten animals were all located to the north and northeast of Lung Kwu
Chau (Figure 3 of Appendix J). This distribution
pattern was drastically different from the baseline period, when the larger
dolphin groups were distributed more evenly in NWL waters with a few more
sighted in NEL waters (Figure 3 of Appendix J).
3.5.33
Notably, none of the larger dolphin groups were sighted near the HKLR03
reclamation site during the present monitoring period (Figure 3 of Appendix J).
Habitat Use
3.5.34
From June to August 2015, the only area being heavily utilized by
Chinese White Dolphins was around Lung Kwu Chau in North Lantau waters (Figures 4a and 4b of Appendix J). Only one grid in NEL recorded the presence of dolphin in the present
quarter with low DPSE value (Figures 4b of Appendix J). Moreover, all grids near
HKLR03/HKBCF reclamation sites, TMCLKL alignment did not record any presence of
dolphins during on-effort search in the present quarterly period, but a few
grids in the vicinity of HKLR09 alignment recorded moderate dolphin densities (Figures 4b of Appendix J).
3.5.35 It should be emphasized that the
amount of survey effort collected in each grid during the three-month period
was fairly low (6-12 units of survey effort for most grids), and therefore the
habitat use pattern derived from the three-month dataset should be treated with
caution. A more complete picture of
dolphin habitat use pattern will be presented when more survey effort for each
grid will be collected throughout the impact phase monitoring programme.
3.5.36
When compared with the habitat
use patterns during the baseline period, dolphin usage in NEL and NWL has
dramatically diminished in both areas during the present impact monitoring
period (Figure 5 of Appendix J). During the
baseline period, many grids between Siu Mo To and Shum Shui Kok recorded
moderately high to high dolphin densities, which was in stark contrast to rare
occurrence of dolphins during the present impact phase period (Figure 5 of Appendix J).
3.5.37
The density patterns were also very different in NWL between the
baseline and impact phase monitoring periods, with higher dolphin usage around
Sha Chau, near Black Point, to the west of the airport, as well as between
Pillar Point and airport platform during the baseline period. In contrast, only the Lung Kwu Chau area
recorded high densities of dolphins during the present impact phase period (Figure 5 of Appendix J).
Mother-calf Pairs
3.5.38
During the present quarterly
period, no young calves (i.e. unspotted calves or unspotted juveniles) for the third consecutive quarter among the eleven quarters of impact
phase monitoring. This absence of young calves is also
in stark contrast to their regular occurrence during the baseline period. Their absences should be of a serious
concern, and the occurrence of calves should be closely monitored in the
upcoming quarters.
Activities and
Associations with Fishing Boats
3.5.39
Only one dolphin group was
associated with feeding activity, while none of the 12 dolphin groups was associated
with socializing, traveling or milling/resting activity during the three-month
study period. The percentage of sightings associated with feeding activities during
the present impact phase period (8.3%) was similar to the one recorded during
the baseline period (11.6%).
However, the sample sizes on total numbers of dolphin sightings were
very different between the two periods.
3.5.40
Distribution of dolphins engaged in various activities during the
present three-month period and baseline period is shown
in Figure 6 of Appendix J. The only sighting engaged in feeding
activity was located near Lung Kwu Chau (Figure
6 of Appendix J). When compared to the baseline period,
distribution of dolphin activities in the present quarter was drastically different
during the present impact phase monitoring quarter (Figure 6
of Appendix J).
3.5.41
As consistently recorded in the past monitoring quarters, none of the
twelve dolphin groups was found to be associated with operating fishing vessels
in North Lantau waters during the present impact phase period.
Photo-identification
and Individual Range Use
3.5.42 From June to August 2015, over 1,500
digital photographs of Chinese White Dolphins were taken during the impact
phase monitoring surveys for the photo-identification work.
3.5.43
In total, 21 individuals
sighted 30 times altogether were identified (see summary table in Annex III of Appendix J and photographs of
identified individuals in Annex IV of Appendix J). All of these
re-sightings were made in NWL. The lone dolphin sighted in NEL during this
quarter was too elusive to be photographed for identification.
3.5.44
The majority of identified individuals were sighted only once during the
three-month period, with the exception of three individuals (CH34, NL136 and
NL310) being twice and another three individuals (NL104, NL202 and NL286) being
sighted thrice.
3.5.45
Notably, four of these 21
individuals (NL136, NL293, WL05 and WL124) were also sighted in West Lantau
waters during the HKLR09 monitoring surveys during June to August 2015, implying
that they have moved across the HKLR09 bridge alignment during the same
three-month period.
Individual range use
3.5.46 Ranging patterns of the 21 individuals
identified during the three-month study period were determined by fixed kernel
method, and are shown in Annex V of Appendix J.
3.5.47 All identified dolphins sighted
in this quarter were utilizing their range use in NWL, but have avoided the NEL
waters where many of them have utilized as their core areas in the past (Annex V of Appendix J). This is in contrary to
the extensive movements between NEL and NWL survey areas observed in the
earlier impact monitoring quarters as well as during the baseline period.
3.5.48
Notably, one individual (NL136) consistently
sighted in NWL and NEL waters in the past have extended its range use to WL
waters in the present quarter. In
the upcoming quarter, individual range use and movements should be continuously
monitored to examine whether there has been any consistent shifts of individual
home ranges from North Lantau to West or Southwest Lantau, as such shift could
possibly be related to the HZMB-related construction works.
Action Level / Limit
Level Exceedance
3.5.49
There was one Limit Level exceedance of dolphin
monitoring for the quarterly monitoring data (June 2015 ˇV August 2015). According
to the contractorˇ¦s information, the marine activities undertaken for HKLR03
during the quarter of June to August 2015 included reclamation, excavation of
stone platform, construction of seawall, temporary drainage diversion and
ground investigation. 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 since the impact phase
(October 2012). It should also be noted that reclamation work under HKLR03
(adjoining the Airport Island) situates in waters which has rarely been used by
dolphins in the past, and the working vessels under HKLR03 have been travelling
from source to destination in accordance with the Marine Travel Route to
minimize impacts on Chinese White Dolphin.
In addition, the contractor will implement proactive mitigation measures
such as avoiding anchoring at Marine Departmentˇ¦s designated anchorage site ˇV
Sham Shui Kok Anchorage (near Brothers Island) as far as practicable.
3.5.50
A two-way ANOVA with repeated measures and unequal
sample size was conducted to examine whether there were any significant
differences in the average encounter rates between the baseline and impact
monitoring periods. The two
variables that were examined included the two periods (baseline and impact
phases) and two locations (NEL and NWL).
3.5.51
For the comparison between the baseline period and
the present quarter (eleventh quarter of the impact phase being assessed), the
p-value for the differences in average dolphin encounter rates of STG and ANI
were 0.0064 and 0.0270 respectively.
If the alpha value is set at 0.05, significant differences were detected
between the baseline and present quarters in both dolphin encounter rates of
STG and ANI.
3.5.52
For the comparison between the baseline period and
the cumulative quarters in impact phase (i.e. first eleven quarters of the
impact phase being assessed), the p-value for the differences in average
dolphin encounter rates of STG and ANI were 0.0002 and 0.00005
respectively. Even if the alpha
value is set at 0.01, significant differences were detected in both the average
dolphin encounter rates of STG and ANI (i.e. between the two periods and the
locations).
3.5.53
The AFCD monitoring data during June 2015 to August
2015 has been reviewed by the dolphin specialist. During the same quarter, no dolphin was
sighted from 48.04 km of survey effort on primary lines in NEL, while five
groups of 25 dolphins were sighted from 100.65 km of survey effort on primary
lines in NWL. This review has
confirmed that the low occurrence of dolphins reported by the HKLR03 monitoring
surveys in summer 2015 in NEL survey area is accurate.
3.5.54
There is no evidence showing that the sources of
impact directly related to the construction works of HKLR03 that may have
affected the dolphin usage in the NEL region.
3.5.55
All dolphin protective measures are fully and
properly implemented in accordance with the EM&A Manual. According to the
Marine Travel Route Plan, if vessels are crossing along edge of the proposed
marine park, the travelling speed will keep not exceeding 5 knots when crossing
the edge of the proposed marine park. The Contractor will continue to provide
training for skippers to ensure that their working vessels travel from source
to destination to minimize impacts on Chinese White Dolphin and avoid anchoring
at Marine Departmentˇ¦s designated anchorage site - Sham Shui Kok Anchorage
(near Brothers Island) as far as practicable. Also, it is recommended to
complete the marine works of the Contract as soon as possible so as to reduce
the overall duration of impacts and allow the dolphins population to recover as
early as possible.
3.5.56
A meeting was held on 6 October 2015 with
attendance of representative of Highways Department, ENPO, Resident Site Staff
(RSS), Environmental Team (ET) and dolphin specialist for Contract Nos.
HY/2010/02, HY/2011/03, HY/2012/07, HY/2012/08. Also, main Contractor for
Contract Nos. HY/2012/07 and HY/2012/08 attended the meeting. The
discussion/recommendation as recorded in the minutes of the meeting, which
might be relevant to HKLR03 Contract are summarized below.
3.5.57
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.
3.5.58
It was reminded that the ETs shall keep reviewing
the implementation status of the dolphin related mitigation measures and remind
the contractor to ensure the relevant measures were fully implemented.
3.5.59
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
It was suggested that the protection measures
(e.g., speed limit control) for the proposed Brothers Island Marine Park (BMP)
shall be brought forward as soon as possible before its establishment so as to
provide a better habitat for dolphin recovery. It was noted that under the
Regular Marine Travel Route Plan, the contractors have committed to reduce the
vessel speed in BMP.
3.5.62
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 14 June 2015. 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 2015)
|
Monitoring Station
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
810291.160
|
816678.727
|
0.950
|
810291.164
|
816678.734
|
1.033
|
S2
|
810958.272
|
815831.531
|
0.864
|
810958.282
|
815831.519
|
0.953
|
S3
|
810716.585
|
815953.308
|
1.341
|
810716.562
|
815953.324
|
1.440
|
S4
|
811221.433
|
816151.381
|
0.931
|
811221.466
|
816151.504
|
1.094
|
Table 3.10 Comparison
of Measurement
|
Comparison of measurement
|
Remarks and
Recommendation
|
Monitoring Station
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
0.004
|
0.006
|
0.083
|
Level continuously
increased
|
S2
|
0.010
|
-0.012
|
0.089
|
Level continuously
increased
|
S3
|
-0.023
|
0.016
|
0.099
|
Level continuously
increased
|
S4
|
0.033
|
0.122
|
0.163
|
Level continuously
increased
|
3.6.2
This measurement result was generally and relatively higher than the
baseline measurement at S1, S2, S3 and S4.
The mudflat level is continuously increased.
Water Quality
Monitoring
3.6.3
The mudflat monitoring covered water quality
monitoring data. Reference was made
to the water quality monitoring data of the representative water quality
monitoring station (i.e. SR3) as in the EM&A Manual. The water quality monitoring location
(SR3) is shown in Figure 2.1.
3.6.4 Impact water quality
monitoring in San Tau (monitoring station SR3) was conducted in June 2015. The
monitoring parameters included dissolved oxygen (DO), turbidity and suspended
solids (SS).
3.6.5 The
Impact monitoring result for SR3 were extracted and summarised below:
Table 3.11 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)
|
1-Jun-15
|
6.65
|
8.70
|
7.50
|
6.55
|
8.50
|
6.05
|
3-Jun-15
|
6.31
|
13.10
|
17.00
|
6.33
|
5.00
|
4.75
|
5-Jun-15
|
5.86
|
9.55
|
10.65
|
6.74
|
6.20
|
5.20
|
8-Jun-15
|
6.98
|
5.40
|
8.05
|
7.07
|
3.15
|
7.15
|
10-Jun-15
|
7.07
|
4.55
|
4.75
|
8.10
|
3.90
|
5.05
|
12-Jun-15
|
7.53
|
5.55
|
9.35
|
9.96
|
2.75
|
7.40
|
15-Jun-15
|
6.56
|
7.80
|
3.30
|
8.98
|
6.05
|
9.10
|
17-Jun-15
|
7.29
|
6.15
|
4.25
|
7.38
|
4.95
|
4.30
|
19-Jun-15
|
6.75
|
6.60
|
6.40
|
6.79
|
7.15
|
4.45
|
22-Jun-15
|
6.76
|
6.45
|
8.45
|
7.06
|
3.85
|
5.25
|
24-Jun-15
|
6.48
|
7.30
|
5.15
|
6.33
|
4.80
|
3.95
|
26-Jun-15
|
5.88
|
5.15
|
3.20
|
6.68
|
3.90
|
3.10
|
29-Jun-15
|
8.20
|
6.65
|
3.65
|
10.29
|
7.30
|
3.90
|
Average
|
6.79
|
7.15
|
7.05
|
7.56
|
5.19
|
5.36
|
Mudflat Ecology Monitoring
Sampling Zone
3.6.6
In order to collect baseline
information of mudflats in the study site, the study site was divided into
three sampling zones (labeled as TC1, TC2, TC3) in Tung Chung Bay and one zone
in San Tau (labeled as ST). The horizontal length of sampling zones TC1, TC2,
TC3 and ST were about 250 m, 300 m, 300 m and 250 m, respectively. Survey of
horseshoe crabs, seagrass beds and intertidal communities were conducted in
every sampling zone. The present survey
was conducted in June 2015 (totally 6 sampling
days between 6th and 20th June 2015). The locations of
sampling zones are shown in Annex I of Appendix O.
Horseshoe Crabs
3.6.7
Active search method was conducted for horseshoe crab monitoring by two experienced
surveyors at every sampling zone. During the search period, any accessible and
potential area would be investigated for any horseshoe crab individuals within
2-3 hours in low tide period (tidal level below 1.2 m above Chart Datum
(C.D.)). Once a horseshoe crab individual was found, the species was identified
referencing to Li (2008). The prosomal width, inhabiting substratum and
respective GPS coordinate were recorded. A photographic record was taken for
future investigation. Any grouping behavior of individuals, if found, was
recorded. The horseshoe crab surveys were conducted on 16th (for TC3
and ST) and 17th (for TC1 and TC2) June 2015. The weather was hot and sunny on
both survey days.
Seagrass Beds
3.6.8 Active search method was
conducted for seagrass bed monitoring by two experienced surveyors at every
sampling zone. During the search period, any accessible
and potential area would be investigated for any seagrass beds within 2-3 hours in low tide period. Once seagrass bed was found, the species, estimated area, estimated coverage
percentage and respective GPS coordinate were recorded. A photographic record was taken for future investigation. The seagrass beds surveys were
conducted on 16th (for TC3 and ST) and 17th (for TC1 and
TC2) June 2015. The weather was hot and sunny on both survey days.
Intertidal Soft Shore Communities
3.6.9 The intertidal soft shore
community surveys were conducted in low tide period on 6th (for ST),
14th (for TC2), 15st (for TC3) and 20thJune
2015 (for TC1). At each sampling zone, three 100 m horizontal transects were laid at high tidal level (H: 2.0 m above C.D.), mid
tidal level (M: 1.5 m above C.D.) and low tidal level (L: 1.0 m above C.D.). Along every horizontal transect, ten random quadrats (0.5 m x 0.5m) were placed.
3.6.10 Inside a quadrat,
any visible epifauna were collected and were in-situ identified to the lowest practical taxonomical resolution.
Whenever possible a hand core sample (10 cm internal diameter ´ 20 cm depth) of sediments was collected in the quadrat. The core sample was gently washed through a sieve of mesh size 2.0 mm in-situ. Any
visible infauna were collected and identified. Finally the top 5 cm surface
sediments was dug for visible infauna in the quadrat regardless of hand core
sample was taken.
3.6.11 All collected fauna were released after recording except some tiny
individuals that are too small to be identified on
site. These tiny individuals were taken to
laboratory for identification under dissecting microscope.
3.6.12 The taxonomic classification was conducted in accordance to the
following references: Polychaetes: Fauchald (1977), Yang and Sun (1988); Arthropods: Dai and Yang (1991), Dong (1991); Mollusks: Chan and Caley (2003),
Qi (2004).
Data Analysis
3.6.13
Data collected from direct search and core sampling
was pooled in every quadrat for data analysis. Shannon-Weaver Diversity Index
(Hˇ¦) and Pielouˇ¦s Species Evenness (J) were calculated for every quadrat using
the formulae below,
Hˇ¦= -ŁU ( Ni / N ) ln ( Ni / N ) (Shannon and Weaver,
1963)
J = Hˇ¦ / ln
S, (Pielou, 1966)
where S is
the total number of species in the sample, N is the total number of
individuals, and Ni is the number of individuals of the ith species.
Mudflat Ecology Monitoring Results and Conclusion
Horseshoe Crabs
3.6.14
In general, two species of
horseshoe crab Carcinoscorpius
rotundicauda (total 66 ind.) and Tachypleus
tridentatus (total 18 ind.) were recorded in the survey area. All
individuals were mainly found on fine sand or soft mud substrata. The group
size varied from 2 to 8 individuals for every sight record. Although less
number of Tachypleus tridentatus was
recorded, the average body size was larger than that of Carcinoscorpius rotundicauda. Photo records were shown in Figure 3.1 of Appendix O while the complete records
of horseshoe crab survey in every sampling zone were shown in Annex II of Appendix O.
3.6.15
Table 3.1 of Appendix O summarizes the survey
results of horseshoe crab in present survey. For Carcinoscorpius rotundicauda, it could be found in all sampling zones
while more individuals were recorded in TC1 and TC3 (TC1: 24 ind., TC2: 1 ind.,
TC3: 34 ind., ST: 7 ind.). The search record was 6.0 ind. hr-1 person-1, 0.3
ind. hr-1 person-1, 5.7 ind. hr-1 person-1, 1.2 ind. hr-1 person-1 in TC1, TC2,
TC3 and ST respectively. Relatively TC3 was highest in number of individuals
but lots of individuals were smaller in size (mean prosomal width: 27.81 mm).
Less numbers of individuals were found in TC1 and ST but most of them were
larger in size (TC1: 40.01 mm, ST: 48.96 mm). The largest individual reached
92.05 mm in TC1.
3.6.16
For Tachypleus tridentatus, it could be found in TC3 and ST only. There
were 9 individuals found in both sampling zones while search record was 1.5
ind. hr-1 person-1. The mean prosomal widths were similar between two sampling
zones (TC3: 50.31 mm, ST: 63.67 mm). The largest individual reached 118.34 mm
in ST (Figure 3.1 of Appendix O).
3.6.17
In the previous survey of Mar.
2015, there was one important finding that a mating pair of Carcinoscorpius rotundicauda was found
in ST (prosomal width: male 155.1 mm, female 138.2 mm) (Figure 3.2 of Appendix O). It indicated the
importance of ST as a breeding ground of horseshoe crab. Moreover, two moults
of Carcinoscorpius rotundicauda were
found in TC1 with similar prosomal width 130-140 mm (Figure 3.2 of Appendix O). It reflected that a
certain numbers of moderately sized individuals inhabited the sub-tidal habitat
of Tung Chung Wan after its nursery period on soft shore. These individuals
might move onto soft shore during high tide for feeding, moulting and breeding.
Then it would return to sub-tidal habitat during low tide. Because the mating
pair should be inhabiting sub-tidal habitat in most of the time. The record was
excluded from the data analysis to avoid mixing up with juvenile population
living on soft shore.
3.6.18
No marked individual of
horseshoe crab was recorded in present survey. Some marked individuals were
found in previous surveys conducted in September 2013, March 2014 and September
2014. All of them were released through a conservation programme conducted by
Prof. Paul Shin (Department of Biology and Chemistry, The City University of
Hong Kong (CityU)). It was a re-introduction trial of artificial bred horseshoe
crab juvenile at selected sites. So that the horseshoe crabs population might
be restored in the natural habitat. Through a personal conversation with Prof.
Shin, about 100 individuals were released in the sampling zone ST on 20 June
2013. All of them were marked with color tape and internal chip detected by
specific chip sensor. There should be second round of release between June and
September 2014 since new marked individuals were found in the survey of
September 2014.
3.6.19
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
3.6.20
Figures 3.3 and 3.4 of Appendix
O show the changes of
number of individuals, mean prosomal width and search record of horseshoe crabs
Carcinoscorpius rotundicauda and Tachypleus tridentatus
respectively in every sampling zone along the sampling months. In general,
higher search records (i.e. number of individuals) of both species were always
found in ST followed by TC3 from September 2012 to September 2014. Then the
search record in TC3 was even higher than that in ST from March 2015 to June
2015. For TC1, the search record was at low to medium level and fluctuated
slightly along the sampling months. In contrast, much lower search record was
found in TC2 (2 ind. in Sep. 2013, 1 ind. in Mar., Jun., Sep. 2014, Mar. and
Jun 2015). Although there was no obvious spatial difference of horseshoe crab
size (prosomal width) among the sampling zones, larger individuals (prosomal
width > 80 mm) were usually found in TC1 and ST.
3.6.21
Throughout the monitoring period conducted,
it was obvious that TC3 and ST (western shore of Tung Chung Wan) was an
important nursery ground for horseshoe crab especially newly hatched
individuals due to larger area of suitable substratum (fine sand or soft mud)
and less human disturbance (far from urban district). Relatively, other
sampling zones were not a suitable nursery ground especially TC2. Possible
factors were less area of suitable substratum (especially TC1) and higher human
disturbance (TC1 and TC2: close to urban district and easily accessible). In
TC2, large daily salinity fluctuation was a possible factor either since it was
flushed by two rivers under tidal inundation. The individuals found in TC1 and
TC2 were believed migrating from TC3 and ST during high tide while it might
leave over a certain period of time. It accounted for the variable search
records in the sampling zones along the sampling months. For example, few
individuals of Tachypleus tridentatus were found in TC1 only between
September 2012 and September 2013. However it no longer appeared while few
individuals of Carcinoscorpius rotundicauda were found after March 2014.
Seasonal variation of horseshoe crab population
3.6.22 Throughout the monitoring period
conducted, the search record of horseshoe crab declined obviously during dry
season especially December (Figures 3.3
and 3.4 of Appendix O). No individual of horseshoe crabwas found in the
survey of December 2013. Next year, 2 individuals of Carcinoscorpius rotundicauda and 8 individuals of Tachypleus tridentatus were found only
in December 2014. As mentioned, the horseshoe crabs were inactive and burrowed
in the sediments during cold weather (<15 ºC). Similar results of low search
record in dry season were reported in a previous territory-wide survey of
horseshoe crab. For example, the search records in Tung Chung Wan were 0.17
ind. hr-1 person-1and 0 ind. hr-1 person-1in wet season and dry season
respectively (details see Li, 2008). After the dry season, the search record
increased with the warmer climate.
3.6.23 Between the sampling months
September 2012 and December 2013, Carcinoscorpius
rotundicauda was a less common species relative to Tachypleus tridentatus. Only 4 individuals were ever recorded in ST
in December 2012. This species had ever been believed of very low density in ST
hence the encounter rate was very low. Since March 2014, it was found in all
sampling zones with higher abundance in ST. Based on its average size (mean
prosomal width 39.28-49.81 mm), it indicated that breeding and spawning of this
species had occurred 3-4 years ago along the coastline of Tung Chun Wan.
However, these individuals were still small while their walking trails were
inconspicuous. Hence there was no search record in previous sampling months.
From March 2014 to June 2015, more individuals were recorded due to larger size
and higher activity. Focused on June 2015 (present survey), more small sized
individuals (prosomal width 10-20 mm) were found in TC3 (specifically soft mud
area between TC3 and ST), it indicated another round of successful breeding and
spawning of Carcinoscorpius rotundicauda
along the western shore of Tung Chung Wan. It matched with the previous mating
record in March 2015.
3.6.24 For Tachypleus tridentatus, sharp increase of number of individuals was
recorded in ST with wet season (from March to September 2013). According to a
personal conversation with Prof. Shin (CityU), his monitoring team had recorded
similar increase of horseshoe crab population during wet season. It was
believed that the suitable ambient temperature increased its conspicuousness.
However similar pattern was not recorded during the wet season of 2014. The
number of individuals increased in March and June 2014 followed by a rapid
decline in September 2014. The number of individuals showed a general
decreasing trend from March 2014 to June 2015. Apart from natural mortality,
migration from nursery soft shore to subtidal habitat was another possible
cause. Since the mean prosomal width of Tachypleus
tridentatus continued to grow and reached about 50 mm in March 2014. Then
it varied slightly between 50-65 mm from September 2014 to June 2015. Most of
the individuals might have reached a suitable size strong enough to forage in
sub-tidal habitat.
3.6.25 Since TC3 and ST were regarded as
important nursery ground for horseshoe crab, box plots of prosomal width of two
horseshoe crab species were constructed to investigate the changes of
population in details.
Box plot of horseshoe crab populations in ST
3.6.26 Figure 3.6 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 June 2015, the size of major population (50% records between upper and
lower quartile) fluctuated between 30-40 mm and 45-60 mm. Similar to TC3, such fluctuation should
be due to variable encounter rate influenced by weather.
3.6.27 For Tachypleus tridentatus, a
consistent growing trend was observed for the major population from December
2012 to December. 2014 regardless of change of search record. The prosomal
width increased from 15-30 mm to 55-70 mm. As mentioned, the large individuals
might have reached a suitable size for migrating from the nursery soft shore to
subtidal habitat. From March to June 2015, the size of major population
decreased slightly with prosomal width 40-60 mm. It further indicated some of
order individuals might have migrated to sub-tidal habitat
Impact of the HKLR project
3.6.28 The present survey was the 11th
time of the EM&A programme during the construction period. Based on the
results, impact of the HKLR project could not be detected on horseshoe crabs
considering the factor of natural, seasonal variation. In case, abnormal
phenomenon (e.g. very few numbers of horseshoe crab individuals in warm
weather, large number of dead individuals on the shore) is observed, it would
be reported as soon as possible.
Seagrass Beds
3.6.29
In general, two species of
seagrass Halophila ovalis and Zostera japonica were recorded in ST
only. Both species were found on sandy substratum nearby the seaward side of
mangrove vegetation at 2.0 m above C.D. Photo records were shown in Figure 3.7 of Appendix O while the complete records
of seagrass beds survey were shown in Annex
III of Appendix O.
3.6.30 Table 3.2 of Appendix O summarize the results of
seagrass beds survey in ST. Two long strands (11.8-24.2 m) of Zostera japonica were found. The total
seagrass bed area was about 90.0 m2 (average area 45.0 m2)
while the estimated vegetation coverage was 50-80%. For Halophila ovalis, three small patches (1.0-3.4 m2) were
found coinhabiting with the long strand of Zostera
japonica. The total seagrass bed area was 6.8 m2 (average area 2.3 m2)
while the estimated vegetation coverage was 50-80%.
Temporal variation of seagrass beds
3.6.31 Figure 3.8 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 March 2013 that grew within the large patch of seagrass Halophila
ovalis. Then the patch size increased and merged gradually with the warmer
climate from March to June 2013 (15 m2). However the patch size
decreased sharply and remained similar from September 2013 (4 m2) to
March 2014 (3 m2). In June 2014, the patch size increased obviously
again (41 m2) with warmer climate. Similar to previous year, the
patch size decreased again and remained similar September 2014 (2 m2)
to December 2014 (5 m2). From March to June 2015, the patch size
increased sharply again (90.0 m2) and became the dominant seagrass
in ST. It might be due to the disappearance of the originally dominant seagrass
Halophila ovalis resulting in less competition for substratum and nutrients.
3.6.32
For Halophila
ovalis, it was recorded as 3-4 medium
to large patches (area 18.9-251.7 m2; vegetation coverage 50-80%)
beside the mangrove vegetation at tidal level 2 m above C.D in the September
2012 (First survey). The
total seagrass bed area grew steadily from 332.3 m2 in September
2012 to 727.4 m2 in December 2013. Flowers could be observed in the
largest patch during its flowering period in December 2013. In March 2014, 31 small to
medium patches were newly recorded (variable area 1-72 m2 per patch,
vegetation coverage 40-80% per patch) in lower tidal zone between 1.0 and 1.5 m
above C.D. The total seagrass area increased further to 1350 m2. In
June 2014, these small and medium patches grew and extended to each others.
These patches were no longer distinguishable and were covering a significant
mudflat area of ST. It was generally grouped into 4 large areas (1116 ˇV 2443 m2)
of seagrass beds characterized of patchy distribution, variable vegetable
coverage (40-80%) and smaller leaves. The total seagrass bed area increased
sharply to 7629 m2. In September 2014, the total seagrass area
declined sharply to 1111 m2. There were only 3-4 small to large
patches (6-253 m2) at high tidal level and 1 patch at low tidal
level (786 m2). Typhoon or strong water current
was a possible cause
(Fong, 1998). In September 2014, there were two tropical cyclone records in
Hong Kong (7th-8th September: no cyclone name, maximum
signal number 1; 14th-17th September: Kalmaegi maximum
signal number 8SE) before the seagrass survey dated 21st September
2014. The strong water current caused by the cyclone, Kalmaegi especially,
might have given damage to the seagrass beds. In addition, natural heat stress
and grazing force were other possible causes reducing seagrass beds area.
Besides, Halophila ovalis could be found in other
mud flat area surrounding the single patch. But it was hardly distinguished
into patches due to very low coverage (10-20%) and small leaves.
3.6.33 In December 2014, all the seagrass patches of Halophila ovalis disappeared in ST. Figure
3.9 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 can
colonize areas in short period but disappears quickly under unfavourable
conditions (Fong, 1998).
Unfavourable conditions to seagrass Halophila ovalis
3.6.34 Typhoon or strong water current was suggested as one unfavourable condition to Halophila ovalis (Fong, 1998). As
mentioned above, there were two tropical cyclone records in Hong Kong in
September 2014. The strong water current caused by the cyclones might have
given damage to the seagrass beds.
3.6.35 Prolonged light deprivation due to turbid water would be another
unfavouable condition. Previous studies reported that Halophila ovalis had little tolerance to
light deprivation. During experimental darkness,
seagrass biomass declined rapidly after 3-6 days and seagrass died completely
after 30 days. The rapid death might be due to shortage of available
carbohydrate under limited photosynthesis or accumulation of phytotoxic end
products of anaerobic respiration (details see Longstaff et al., 1999). Hence the seagrass bed of this species was susceptible
to temporary light deprivation events such as flooding river runoff (Longstaff and Dennison, 1999).
3.6.36 In order to investigate any
deterioration of water quality (e.g. more turbid) in ST, the water quality
measurement results at two closest monitoring stations SR3 and IS5 of the
EM&A programme were obtained from the water quality monitoring team. Based
on the results from June to December 2014, the overall water quality was in
normal fluctuation except there was one exceedance of suspended solids (SS) at
both stations in September. On 10th September, 2014, the SS
concentrations measured at mid-ebb tide at stations SR3 (27.5 mg/L) and IS5
(34.5 mg/L) exceeded the Action Level (≤23.5 mg/L and 120% of upstream control stationˇ¦s reading) and Limit
Level (≤34.4 mg/L
and 130% of upstream control stationˇ¦s reading) respectively. The turbidity
readings at SR3 and IS5 reached 24.8-25.3 NTU and 22.3-22.5 NTU respectively.
The temporary turbid water should not be caused by the runoff from upstream
rivers. Because there was no rain or slight rain from 1st to 10th
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 ˇĄNotifications of
Environmental Quality Limits Exceedancesˇ¦ provided by the respective environmental
team. The respective construction of seawall and stone column works, which
possibly caused turbid water, were carried out within silt curtain as
recommended in the EIA report. Moreover there was no leakage of turbid water,
abnormity or malpractice recorded during water sampling. In general, the
exceedance of suspended solids concentration was considered to be attributed to
other external factors, rather than the contract works.
3.6.37
Based on the weather condition and water quality results in ST, the
co-occurrence of cyclone hit and turbid waters in September 2014 might have
combined the adverse effects on Halophila
ovalis that leaded to disappearance of
this short-lived and r-strategy
seagrass species. Fortunately Halophila
ovalis was a fast-growing species (Vermaat et al., 1995). Previous
studies showed that the seagrass bed could be recovered to the original sizes
in 2 months through vegetative propagation after experimental clearance
(Supanwanid, 1996). Moreover it was reported to recover rapidly in less than 20
days after dugong herbivory (Nakaoka and Aioi, 1999). As mentioned, the
disappeared seagrass in ST in 1995 could recover gradually after the completion
of reclamation works for international airport (Fong, 1998). The seagrass beds
of Halophila ovalis might recolonize the
mudflat of ST through seed reproduction as long as there was no unfavourable
condition in the coming months.
3.6.38
From March to
June 2015, 2-3 small patches of Halophila ovalis were newly found
coinhabiting with another seagrass species Zostera japonica.
But its total patch area was still very low relative to the previous records.
The recolonization rate was low while cold weather and insufficient sunlight
were possible factors between December 2014 and March 2015. Moreover, it would
need to complete with more abundant seagrass Zostera
japonica for substratum and nutrient. Since Zostera japonica had extended and had
covered the original seagrass bed of Halophila ovalis at certain degree. Therefore it was too early to conclude if Halophila ovalis would recolonize to its original size. Or the
dominance of seagrass bed would be replaced by Zostera
japonica. Regular monitoring was necessary.
3.6.39
In previous survey of Mar. 2015, labelled sticks were inserted in the
area where used to be the seagrass patch of highest coverage. Through informal
enquiry with AFCD staffs on site, the sticks were used to trace the
recolonization pattern of seagrass after the rapid disappearance reported in
December 2014. However, all labeled sticks were removed and were no longer seen
in present survey (June 2015).
Impact of the HKLR
project
3.6.40
The present survey was the 11th survey of the EM&A
programme during the construction period. According to the results of present
survey, there was recolonization of both
seagrass species Halophila
ovalis
and Zostera japonica in ST. The seagrass patches were predicted to
increase in the coming warm season. Hence the negative impact of HKLR project on the
seagrass was not significant. In case, adverse
phenomenon (e.g. reduction of seagrass patch size, abnormal change of leave colour) is observed
again, it would be reported as soon as possible.
Intertidal Soft Shore Communities
3.6.41 Table 3.3 and
figure 3.10 of Appendix O show the types of substratum along the horizontal transect at every
tidal level in every sampling zone. The relative distribution of different substrata was
estimated by categorizing the substratum types (Gravels & Boulders / Sands /
Soft mud) of the ten random quadrats along the horizontal transect. The distribution of substratum types varied
among tidal levels and sampling:
ˇP
In TC1, high percentage of ˇĄGravels and Bouldersˇ¦ was recorded (80-100%)
at high and mid tidal levels. But the substratum type was diverse relatively at
low tidal level. Higher percentage of ˇĄSandsˇ¦ (50%) was recorded followed by
ˇĄGravels and Bouldersˇ¦ (30%) and ˇĄSoft mudˇ¦ (20%).
ˇP
In TC2, the substratum distribution was similar at high and mid tidal
levels. Higher percentage of ˇĄSandsˇ¦ (60%) was recorded followed by ˇĄGravels
and Bouldersˇ¦ (30%). At low tidal level, the major substratum was ˇĄSoft mudˇ¦
(90%).
ˇP
In TC3, the substratum type was clearly different between high-mid tidal
level and low tidal level. ˇĄSandsˇ¦ was the main substratum type (100%) at high
and mid tidal levels while ˇĄGravels and Bouldersˇ¦ was the main substratum type
(90%) at low tidal level.
ˇP
In ST, the substratum type was clearly different between high-mid tidal
level and low tidal level. ˇĄGravels and Bouldersˇ¦ (100%) was the main
substratum at high and mid tidal levels. The main substratum type was either
ˇĄSoft mudˇ¦ (50%) and ˇĄSandsˇ¦ (40%) at low tidal level.
3.6.42 There was neither consistent
vertical nor horizontal zonation pattern of substratum type in all sampling zones. Such heterogeneous variation should be caused by different hydrology (e.g. wave in
different direction and intensity) received by the four sampling zones.
3.6.43 Table 3.4 of Appendix O lists the total abundance, density and number of taxon of every phylum in this survey. A total of 13359 individuals were recorded. Mollusca was significantly the most abundant phylum (total individuals 12895, density 430
ind. m-2, relative abundance 96.5%). The second abundant phylum was Arthropoda (272 ind., 9 ind. m-2,
2.0%). The third and fourth abundant
phyla were Annelida (84 ind., 3 ind. m-2, 0.6%) and Sipuncula (62 ind., 2 ind. m-2,
0.5%). Relatively
other phyla were very low in abundances (density £1 ind. m-2, relative abundance £0.2%). Moreover, the most diverse phylum was Mollusca (37 taxa) followed by Arthropoda (12 taxa) and Annelida (8 taxa). There were 1-2
taxa recorded only for other phyla. The complete list of collected specimens is shown in Annex
V of Appendix O.
3.6.44 Table 3.5 of Appendix O show the number of individual, relative abundance and density of each phylum in every sampling zone. The total abundance (3194-4481 ind.) varied among the four sampling
zones while the phyla
distributions were similar. In general, Mollusca was the most dominant phylum (no. of
individuals: 3119-4357
ind.; relative abundance
96.6-97.7%; density 416-581 ind. m-2). Other phyla were significantly lower in number of individuals. Arthropoda was the second abundant
phylum (23-90
ind.; 0.7-2.6%; 3-12 ind.
m-2). Annelida
was the third abundant
phylum (20-31 ind.; 0.5-0.9%; 3-4 ind. m-2)
in TC1, TC2 and TC3. Sipuncula was the third or fourth abundant phylum (20-24
ind.; 0.6-0.7%; 3 ind. m-2) in TC3 and ST. Cnidaria (sea anemone)
was the fourth abundant phylum (14 ind.; 0.4%; 2 ind. m-2) in ST. Relatively, other phyla were low in abundance among the four sampling zones (≤ 0.3%).
Dominant
species in every sampling zone
3.6.45
Table 3.6 of Appendix O lists the abundant species (relative
abundance >10%) in every sampling zone. In TC1, gastropod Batillaria multiformis was the most abundant clearly (698 ind. m-2, relative abundance 82%) at high tidal level (major substratum: ˇĄGravels
and Bouldersˇ¦). It was also the most abundant species at moderate-high density (264 ind. m-2, 45%) at mid tidal level (major substratum: ˇĄGravels
and Bouldersˇ¦). Gastropod Monodonta labio (60-117 ind. m-2, 17-20%) was the second abundant species at low to moderate density at mid and
low tidal levels. Gastropod Cerithidea djadjariensis (80 ind. m-2, 13%) was the third abundant species at low density
at mid tidal level. At low tidal level (major substratum: ˇĄSandsˇ¦), rock oyster Saccostrea
cucullata (111 ind. m-2, 32%,
attached on boulders)
was the most abundant at moderate density at low tidal level. Gastropod Batillaria zonalis (41 ind. m-2, 12%) was the third abundant species at low
density at low tidal level.
3.6.46
At TC2, gastropod Cerithidea
djadjariensis (198 ind. m-2, 45%) was
the most abundant at moderate density at high tidal level (major
substratum: ˇĄSandsˇ¦). Rock oyster Saccostrea
cucullata (70 ind. m-2, 16%) and gastropod Cerithidea cingulata (58 ind. m-2, 13%) were the second and third abundant species
at low density. Relative to high tidal level, the density of every taxon was
much lower and similar at mid and low tidal levels. No dominant species was
determined. At mid tidal level (major substratum: ˇĄSandsˇ¦), rock oyster Saccostrea
cucullata (66 ind. m-2, 25%), gastropods Cerithidea
djadjariensis (57 ind. m-2, 21%) and Batillaria zonalis (35 ind. m-2, 13%) were commonly occurring at low density. At low
tidal level (major substratum: ˇĄSoft mudˇ¦), rock oyster Saccostrea
cucullata (27 ind. m-2, 21%), gastropods Cerithidea
djadjariensis (30 ind. m-2, 23%), Batillaria zonalis (25 ind. m-2, 19%) and barnacle Balanus amphitrite (13 ind. m-2, 10%,
attached on boulders) were commonly occurring at low density.
3.6.47 At TC3, gastropod Cerithidea djadjariensis was the most abundant at moderate-high density (192-298 ind. m-2, 60-64%) at high and mid tidal levels (major substratum: ˇĄSandsˇ¦) followed by gastropod Cerithidea
cingulata (58-116 ind. m-2, 19-24%) at low to moderate density. Besides Batillaria
multiformis (52 ind. m-2, 11%) was the third abundant species at high tidal
level at low density. At
low tidal level
(major substratum: ˇĄGravels and Bouldersˇ¦), gastropod Monodonta labio (255 ind. m-2,
40%) and rock oyster Saccostrea cucullata (229 ind. m-2, 36%) were
both dominant and at moderate-high density.
3.6.48 At ST,
gastropod Batillaria multiformis
was most abundant (276 ind. m-2,
42%) at high tidal
level (major substratum: ˇĄGravels and Bouldersˇ¦) followed by gastropod Monodonta labio (194 ind. m-2, 17%). Both dominant species were at moderate-high
density. At mid tidal level (major substratum: ˇĄGravels and Bouldersˇ¦), gastropod Monodonta labio (154 ind. m-2,
31%) was the most abundant at moderate density.
Other less abundant species were rock oyster Saccostrea
cucullata (89 ind. m-2, 18%) and gastropod Lunella coronata (56 ind. m-2, 11%) at low densities. At low tidal level (major
substrata: ˇĄSandsˇ¦ and ˇĄSoft mudˇ¦), gastropods Lunella coronata (30 ind. m-2, 22%), Batillaria zonalis (21 ind. m-2, 15%), Cerithidea
djadjariensis (16 ind. m-2, 12%), Batillaria bornii (13 ind. m-2, 10%) and rock oyster Saccostrea
cucullata (20 ind. m-2, 15%) were common taxa at low densities.
3.6.49 There was no consistent zonation
pattern of species distribution observed across all sampling zones and tidal levels. The species distribution should be affected by the type of substratum primarily. In general, gastropods Batillaria multiformis (total number of individuals: individuals: 3454 ind., relative
abundance 25.9%), Cerithidea djadjariensis (2395 ind., 17.9%) and Cerithidea cingulata (781 ind., 5.8%) were the most commonly occurring species on sandy and
soft mud substrata. Rock
oyster Saccostrea cucullata (1923 ind., 14.4%) and gastropod Monodonta labio (2227 ind.,
16.7%) were commonly occurring species inhabiting
gravel and boulders substratum.
Biodiversity
and abundance of soft shore communities
3.6.50
Table 3.7 of Appendix O shows the mean values of
number of species, density, biodiversity index Hˇ¦ and species
evenness J of soft shore communities at every tidal level and in every sampling zone. Among the sampling zones, the number of species (7-13 spp. 0.25 m-2)
in ST was relatively higher than other sampling zones (6-11 spp. 0.25 m-2).
The mean Hˇ¦ (1.66) and J (0.74) in ST were relatively higher
than that in TC1, TC2 and TC3 (Hˇ¦:
1.08-1.48; J: 0.54-0.76). The mean
densities were highly variable and ranged 129-849 ind. m-2. No
general difference was observed among the sampling zones.
3.6.51 Across the tidal levels, there
was no consistent difference of the mean number of species, Hˇ¦ and J in all sampling zones. For the mean density, a general decreasing
trend was observed from high tidal level to low tidal level at TC1, TC2 and ST.
At TC3, the mean density at low tidal level was higher than that at high and
mid tidal levels. As mentioned, the variation of mean density should be
determined by the type of substratum primarily.
3.6.52 Figures 3.11 to 3.14 of Appendix O show the temporal changes of mean number
of species, mean density,
Hˇ¦ and J at every tidal level
and in every sampling
zone along the sampling months. No consistent
temporal change of any biological parameters was observed. All the parameters
were under slight and natural fluctuation with the seasonal variation.
Impact of
the HKLR project
3.6.53
The present survey was the 11th survey of the EM&A
programme during the construction period. Based
on the results, impacts
of the HKLR project were not detected on
intertidal soft shore community. In case, abnormal phenomenon (e.g. large
reduction of fauna densities and species number) is observed, it would be
reported as soon as possible.
3.7.1
The Contractor registered with EPD as a Chemical Waste
Producer on 12 July 2012 for the Contract. Sufficient numbers of receptacles
were available for general refuse collection and sorting.
3.7.2
The summary of waste flow table is detailed in Appendix K.
3.7.3
The Contractor was reminded that chemical waste
containers should be properly treated and stored temporarily in designated
chemical waste storage area on site in accordance with the Code of Practise on
the Packaging, Labelling and Storage of Chemical Wastes.
3.8
Environmental
Licenses and Permits
3.8.1
The valid environmental licenses and permits during
the reporting period are summarized in Appendix L.
4
Environmental Complaint and
Non-compliance
4.1.1
The detailed air quality, noise, water quality and dolphin exceedances
are provided in Appendix M. Also, the summaries of
the environmental exceedances are presented as follows:
Air
Quality
4.1.2
No
Action and Limit Level exceedances of 1-hour TSP and 24-hour TSP were recorded
at AMS5 during the reporting period.
4.1.3
An
Action Level exceedance of 24-hr TSP level was recorded at AMS6 during the
reporting period. No Action and Limit
Level exceedance of 1-hr TSP level and Limit Level exceedance of 24-hr TSP
level were recorded at AMS6 during the reporting period.
Noise
4.1.4
There were no Action and Limit Level exceedances for noise during
daytime on normal weekdays of the reporting
period.
Water Quality
4.1.1
For marine water quality
monitoring, one Action Level exceedances of suspended solid level were recorded during the reporting month. No Limit Level exceedance of suspended solid level was recorded. No
Action Level/ Limit Level exceedance of turbidity level and dissolved oxygen level were
recorded during the reporting month.
4.1.2
The
construction activities on 26 August 2015 were carried out within silt curtain
as recommended in the EIA Report.
There were no specific activities recorded during the monitoring period that would
cause any significant impacts on the monitoring results. The exceedance of
suspended solid level was considered
to be attributed to other external factors, rather than the contract works.
Therefore, the exceedance was
considered as non-contract related.
The detailed numbers of
exceedances recorded during the reporting period
at each impact station are summarised in Table
4.1.
Dolphin
4.1.3
There was one Limit Level
exceedance of dolphin monitoring for the quarterly monitoring data (June 2015ˇV August 2015). According to the contractorˇ¦s information,
the marine activities undertaken for HKLR03 during the quarter of June to
August 2015 included reclamation, excavation of stone platform, construction of
seawall, temporary drainage diversion and ground investigation.
4.1.4
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 since the
impact phase (October 2012). It should also be noted that reclamation work
under HKLR03 (adjoining the Airport Island) situates in waters which has rarely
been used by dolphins in the past, and the working vessels under HKLR03 have
been travelling from source to destination in accordance with the Marine Travel
Route to minimize impacts on Chinese White Dolphin. In addition, the contractor will
implement proactive mitigation measures such as avoiding anchoring at Marine
Departmentˇ¦s designated anchorage site ˇV Sham Shui Kok Anchorage (near Brothers
Island) as far as practicable.
4.1.5
All dolphin protective measures are fully and properly implemented in
accordance with the EM&A Manual. According to the Marine Travel Route Plan,
if vessels are crossing along edge of the proposed marine park, the travelling
speed will keep not exceeding 5 knots when crossing the edge of the proposed
marine park. The Contractor will continue to provide training for skippers to
ensure that their working vessels travel from source to destination to minimize
impacts on Chinese White Dolphin and avoid anchoring at Marine Departmentˇ¦s
designated anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as
far as practicable. Also, it is recommended to complete the marine works of the
Contract as soon as possible so as to reduce the overall duration of impacts
and allow the dolphins population to recover as early as possible.
Table 4.1 Summary
of Water Quality Exceedances
Station
|
Exceedance Level
|
DO (S&M)
|
DO (Bottom)
|
Turbidity
|
SS
|
Total Number of Exceedances
|
Ebb
|
Flood
|
Ebb
|
Flood
|
Ebb
|
Flood
|
Ebb
|
Flood
|
Ebb
|
Flood
|
IS5
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
26 Aug 2015
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS(Mf)6
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS7
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS8
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS(Mf)9
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS10
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR3
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR4
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR5
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10A
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10B
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Total
|
Action
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
1
|
1**
|
Limit
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0**
|
Notes:
S: Surface;
M: Mid-depth;
** The total exceedances.
4.2
Summary of
Environmental Complaint, Notification of Summons and Successful Prosecution
4.2.1 There were two complaints received during the reporting month. The
summary of environmental complaints is presented in Table
4.2. The details of cumulative statistics of
Environmental Complaints are provided in Appendix N.
Table 4.2 A
Summary of Environmental Complaints for the Reporting Period
Environmental Complaint No.
|
Date of Complaint Received
|
Description of Environmental Complaints
|
COM-2015-074
|
16 July 2015
|
Wastewater splashing from vehicles
|
COM-2015-076
|
17 July 2015
|
Noise
|
4.2.2 No notification of summons and prosecution was received during the
reporting period.
4.2.3 Statistics on notifications of summons and successful prosecutions are
summarized in Appendix M.
5
Comments, Recommendations and Conclusion
5.1.1
According to the environmental
site inspections undertaken during the reporting period, the following
recommendations were provided:
ˇ± The Contractor was reminded to
provide proper treatment for all wastewater generated from the construction
sites prior to discharge.
ˇ± The Contractor was reminded to
remove the rubbish at S16.
ˇ± The Contractor was reminded to
remove the material of abandoned cement mixing plant at S15.
ˇ± The Contractor was reminded to
remove the abandoned water barriers and rubbish at N4.
ˇ± The Contractor was reminded to
provide maintenance for the silt curtains at Portion X.
ˇ± The Contractor was reminded to
provide a drip tray for the diesel container at N4.
ˇ± The Contractor was reminded to
replace the broken green screen at N1.
ˇ± The Contractor was reminded to
provide the water spraying for the stockpiles and unpaved road at S15.
ˇ± The Contractor was reminded to
provide the water spraying for the sand stockpile at S22.
ˇ± The Contractor was reminded to
provide the water spraying for the percussive activity at S8-9.
ˇ± The Contractor was reminded to
provide a standard wheel washing facility at N1.
ˇ± The Contractor was reminded to
remove the concrete waste at N1.
ˇ± The Contractor was reminded to
ensure that the water spraying system works at S15.
ˇ± The Contractor was reminded to remove
the concrete waste at N20 as soon as possible.
ˇ± The Contractor was reminded to
modify the wheel washing bay.
ˇ± The Contractor was reminded to
clean up the construction materials at Harbour Sky No. 68.
ˇ± The Contractor was reminded to
remove stagnant water at site access of N1.
ˇ± The Contractor was reminded to
level the ground to avoid accumulation of water at N1.
ˇ± The Contractor was reminded to
level the ground to avoid accumulation of water at S19 site access.
ˇ± The Contractor was reminded to
provide another silt curtain to fill up the gap at Portion X.
ˇ± The Contractor was reminded to
place sand bags along the gutter at N20.
ˇ± The Contractor was reminded to
provide water sprinkling during piling activity at S11.
ˇ± The Contractor was reminded to
properly cover the cement bags at S11
ˇ± The Contractor was reminded to
remove the accumulated rubbish at S11.
ˇ± The Contractor was reminded to
provide drip trays for chemical containers at S15.
ˇ± The Contractor was reminded to
provide water sprinkling on the unpaved road at S16.
ˇ± The Contractor was reminded to
remove the rubbish at N1.
ˇ± The Contractor was reminded to
clear rubbish regularly at N4.
ˇ± The Contractor was reminded to
provide wheel washing to vehicles before leaving the construction site at S8A.
ˇ± The Contractor was reminded to
conduct construction work properly near the shore at S11 to avoid washing away
sand/silt from construction site into the sea at S11.
ˇ± The Contractor was reminded to provide
enclosure (sheltered on the top and three sides) properly at S19.
ˇ± The Contractor was reminded to
clear stagnant/muddy water and provide proper treatment at S25.
ˇ± The Contractor was reminded to
relocate the silt curtain in accordance with the design plan at Portion X.
ˇ± The Contractor was reminded to
provide cover for the sand stockpile at N4.
ˇ± The Contractor was reminded to
remove the dust material on the ground at S7.
ˇ± The Contractor was reminded to
provide water spraying for the stockpiles at S7.
ˇ± The Contractor was reminded to
provide water spraying for the working platform at S9 to avoid fugitive dust
emission.
ˇ± The Contractor was reminded to
remove the stagnant water inside the I-beams at S11.
ˇ± The Contractor was reminded to
remove the stagnant water inside the drip tray at S15.
ˇ± The Contractor was reminded to
close the doors of the generator at S15.
ˇ± The Contractor was reminded to
remove the rubbish frequently at S19 to avoid accumulation of rubbish.
ˇ± The Contractor was reminded to
provide the silt curtain around the aeronautical light at Portion X.
ˇ± The Contractor was reminded to
connect U-channel to wastewater collection point at N1.
ˇ± The Contractor was reminded to
remove the general waste at N18.
ˇ± The Contractor was reminded to
replace the broken sand bags with new sand bags at N20.
ˇ± The Contractor was reminded to
separate different kind of wastes and disposed of the waste regularly at N20.
ˇ± The Contractor was reminded to
provide water spraying for stone stockpile at S15.
ˇ± The Contractor was reminded to
remove the construction materials at S23.
ˇ± The Contractor was reminded to
remove rubbish frequently at WA6.
ˇ± The Contractor was reminded to
provide drip tray for chemical containers inside West Tunnel.
ˇ± The Contractor was reminded to
provide drip tray for chemical containers under the bridge at West Tunnel.
5.2.1 The impact monitoring programme
for air quality, noise, water quality and dolphin ensured that any
deterioration in environmental condition was readily detected and timely
actions taken to rectify any non-compliance. Assessment and analysis of
monitoring results collected demonstrated the environmental impacts of the
contract. With implementation of the recommended environmental mitigation
measures, the contractˇ¦s environmental impacts were considered environmentally
acceptable. The weekly environmental site inspections ensured that all the
environmental mitigation measures recommended were effectively implemented.
5.2.2
The
recommended environmental mitigation measures, as included in the EM&A
programme, effectively minimize the potential environmental impacts from the
contract. Also, the EM&A programme effectively monitored the environmental
impacts from the construction activities and ensure the proper implementation
of mitigation measures. No particular recommendation was advised for the
improvement of the programme.
5.3.1
The construction phase and
EM&A programme of the Contract commenced on 17 October 2012. This is the twelfth Quarterly EM&A Report which
summarizes the monitoring results and audit findings of
the EM&A programme during the reporting period from 1 June 2015 to 31 August
2015.
Air Quality
5.3.2
No Action Level exceedance and
a Limit Level exceedance of 1-hr TSP level at AMS5 were recorded during the
reporting period. No Action and Limit Level exceedances of 1-hour TSP and
24-hour TSP were recorded at AMS5 during the reporting period.
5.3.3
An Action Level exceedance of
24-hr TSP level at AMS6 were recorded during the reporting period.
Noise
5.3.4
There were no Action and Limit Level exceedances for noise during
daytime on normal weekdays of the reporting period.
Water Quality
5.3.5
4.7.1 For
marine water quality monitoring, one Action Level exceedances of suspended
solid level were recorded during the reporting month. No Limit Level exceedance
of suspended solid level was recorded. No Action Level/ Limit Level exceedance
of turbidity level and dissolved oxygen level were recorded during the
reporting month.
Dolphin
5.3.6
There was one Limit Level exceedance of dolphin monitoring for the
quarterly monitoring data (June
ˇV August 2015).
5.3.7
During this quarter of dolphin
monitoring, no adverse impact from the activities of this construction project
on Chinese White Dolphins was noticeable from general observations.
5.3.8
Although dolphins rarely
occurred in the area of HKLR03 construction in the past and during the baseline
monitoring period, it is apparent that dolphin usage has been significantly
reduced in NEL in 2012-15, and many individuals have shifted away from the
important habitat around the Brothers Islands.
5.3.9
It is critical to monitor the
dolphin usage in North Lantau region in the upcoming quarters, to determine
whether the dolphins are continuously affected by the various construction
activities in relation to the HZMB-related works, and whether suitable
mitigation measure can be applied to revert the situation.
Mudflat -Sedimentation Rate
5.3.10
This measurement result was
generally and relatively higher than the baseline measurement at S1, S2, S3 and
S4. The mudflat level is continuously increased.
Mudflat - Ecology
5.3.11
The June 2015 survey was the eleventh
survey of the EM&A programme during the construction period. Based on the
results, impacts of the HKLR project could not be detected on horseshoe crabs
and intertidal soft shore community. Based on the results, there was
recolonization of both seagrass species Halophila
ovalis and Zostera japonica in
ST. The seagrass patches were predicted to increase in the coming warm
season. Hence the negative impact
of HKLR project on the seagrass was not significant.
Environmental Site Inspection and Audit
5.3.12
Environmental site inspection
was carried out on 3, 10, 17, and 26 June 2015, 2, 8, 16, 22 and 31 July 2015 and
5, 12, 19 and 28 August 2015. Recommendations on remedial actions were given to
the Contractors for the deficiencies identified during the site inspections.
5.3.13
There were two environmental complaints
received during the reporting period.
5.3.14
No notification of summons and
prosecution was received during the reporting period.