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. 15 (March to May 2016)
25 October 2016
Revision 1
Main Contractor Designer
Executive Summary
The Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong
Kong Link Road (HKLR) serves to connect the HZMB Main Bridge at the Hong Kong
Special Administrative Region (HKSAR) Boundary and the HZMB Hong Kong Boundary
Crossing Facilities (HKBCF) located at the north eastern waters of the Hong
Kong International Airport (HKIA).
The HKLR project has been separated into two
contracts. They are Contract No.
HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between
Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter referred to
as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao Bridge Hong
Kong Link Road-Section between HKSAR Boundary and Scenic Hill.
China State Construction Engineering (Hong Kong)
Ltd. was awarded by Highways Department as the Contractor to undertake the
construction works of Contract No. HY/2011/03. The main works of the Contract
include land tunnel at Scenic Hill, tunnel underneath Airport Road and Airport
Express Line, reclamation and tunnel to the east coast of the Airport Island,
at-grade road connecting to the HKBCF and highway works of the HKBCF within the
Airport Island and in the vicinity of the HKLR reclamation. The Contract is part of the HKLR Project
and HKBCF Project, these projects are considered to be ¡§Designated Projects¡¨,
under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap
499) and EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were
prepared for the Project. The
current Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/K for
HKBCF were issued on 22 December 2014 and 11 April 2016, respectively. These
documents are available through the EIA Ordinance Register. The construction
phase of Contract was commenced on 17 October 2012.
BMT 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 fifteenth 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 March 2016 to 31 May 2016.
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
|
March 2016
|
April
2016
|
May 2016
|
Air
Quality
|
1-hr
TSP
|
1, 7, 11, 17 23 and 29
|
1, 7, 12, 18, 22 and 28
|
4, 10, 16, 20, 25 and 31
|
24-hr
TSP
|
4, 10, 16, 21, 24 and 30
|
5, 11, 15, 21 and 27
|
AMS5: 3, 9, 13, 19 and 24
AMS6:
3, 9, 13, 19, 24 and 30
|
Noise
|
1, 7, 17, 23 and 29
|
7, 12, 18 and 28
|
4, 10, 16, 25 and 31
|
Water
Quality
|
2, 4, 7, 9, 11, 14, 16, 18, 21, 23, 25,
28 and 30
|
1, 4, 6, 8, 11, 13, 15, 18, 20, 22, 25,
27 and 29
|
2, 4, 6, 9, 11, 13, 16, 18, 20, 23, 25
and 30
|
Chinese
White Dolphin
|
7, 11, 22 and
23
|
5, 12, 15 and
19
|
3, 12, 17 and
26
|
Mudflat
Monitoring (Ecology)
|
8, 12, 13,
20, 22 and 26
|
--
|
--
|
Mudflat
Monitoring (Sedimentation rate)
|
9
|
--
|
--
|
Site Inspection
|
3,
9, 16, 23 and 29
|
6,
14, 20 and 29
|
4,
11, 18 and 27
|
Due to weather
condition/boat availability, the dolphin monitoring schedule was rescheduled
from 14 March 2016 to 11 March 2016, 21 March 2016 to 22 March 2016, from 11
April 2016 to 12 April 2016, from 6 May 2016 to 12 May 2016, from 16 May 2016
to 17 May 2016 and from 23 May 2016 to 26 May 2016.
Due to change of
weather condition, mudflat monitoring (ecology) was rescheduled from 6 March
2016 to 8 March and from 23 March 2016 to 26 March 2016.
Due to power
interruption and malfunction of HVS at station AMS5, the 24-hr TSP monitoring
at AMS5 on 30 May 2016 was cancelled. A competent person was arranged to repair
the HVS and check the power supply provided for HVS on 7 June 2016.
As Strong Wind Signal
No.3 was hoisted by Hong Kong Observatory on 27 May 2016, water quality
monitoring on 27 May 2016 was cancelled for safety reason. However, due to
safety reason, the water quality monitoring was not carried out on 28 May 2016
because thunderstorm warming was hoisted by Hong Kong Observatory on that day.
Breaches
of Action and Limit Levels
A summary of environmental exceedances for this
reporting period is as follows:
Environmental Monitoring
|
Parameters
|
Action Level (AL)
|
Limit Level (LL)
|
Air Quality
|
1-hr
TSP
|
0
|
0
|
24-hr
TSP
|
0
|
0
|
Noise
|
Leq
(30 min)
|
0
|
0
|
Water Quality
|
Suspended
solids level (SS)
|
0
|
0
|
Turbidity
level
|
0
|
0
|
Dissolved
oxygen level (DO)
|
0
|
0
|
Dolphin Monitoring
|
Quarterly
Analysis (Mar 2016 to May 2016)
|
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 no complaints received in relation to the environmental impacts during the
reporting period.
Notifications of Summons and Prosecutions
There were no notifications of summons or
prosecutions received during this reporting period.
Reporting Changes
This report has been developed in compliance
with the reporting requirements for the 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 team¡¦s observation on 24 March
2014, the original monitoring location of IS(Mf)9 was no longer enclosed by the
perimeter silt curtain of Contract HY/2010/02. Thus, the impact water quality
monitoring works at the original monitoring location of IS(Mf)9 has been
resumed since 24 March 2014.
Transect lines 1, 2, 7, 8, 9 and 11 for dolphin
monitoring have been revised due to the obstruction of the permanent structures
associated with the construction works of HKLR and the southern viaduct of
TM-CLKL, as well as provision of adequate buffer distance from the Airport
Restricted Areas. The EPD issued a
memo and confirmed that they had no objection on the revised transect lines on
19 August 2015.
1.1.2 The
HKLR project has been separated into two contracts. They are Contract
No. HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section
between Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter
referred to as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao
Bridge Hong Kong Link Road-Section between HKSAR Boundary and Scenic Hill.
1.1.3 China
State Construction Engineering (Hong Kong) Ltd. was awarded by Highways
Department (HyD) as the Contractor to undertake the construction works of
Contract No. HY/2011/03. The Contract is part of the HKLR Project and
HKBCF Project, these projects are considered to be ¡§Designated Projects¡¨, under
Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap 499) and
EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were prepared for
the Project. The current
Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/K for HKBCF
were issued on 22 December 2014 and 11 April 2016, respectively. These
documents are available through the EIA Ordinance Register. The construction
phase of Contract was commenced on 17 October 2012. Figure 1.1 shows the project site
boundary.
1.1.5 This
is the fifteenth
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 March 2016 to 31 May 2016.
1.2.1
The project organization
structure and lines of communication with respect to the on-site environmental
management structure with the key personnel contact names and numbers are shown
in Appendix A.
1.3
Construction
Programme
1.3.1
A copy of the Contractor¡¦s construction programme is
provided in Appendix B.
1.4
Construction Works Undertaken During
the Reporting Period
1.4.1
A summary of the construction activities undertaken
during this reporting period is shown in Table 1.1. The Works areas of the Contract are
showed in Appendix
C.
Table 1.1 Construction
Activities during Reporting Period
Description of Activities
|
Site Area
|
Dismantling/trimming
of temporary 40mm stone platform for construction of seawall
|
Portion X
|
Filling
works behind stone platform
|
Portion X
|
Construction
of seawall
|
Portion X
|
Loading
and unloading of filling materials
|
Portion X
|
Pipe
Piling
|
Portion X
|
Construction
of box culvert PR14
|
Portion X
|
Excavation
for diversion of culvert PR10
|
Portion X
|
Excavation
and Lateral support works for Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Construction
of tunnel box structure for Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X
|
Excavation
for HKBCF to Airport Tunnel
|
Portion X
|
Jet Grouting works & Sheet Piling
Works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel)
|
Portion X
|
Excavation
and Lateral Support Works for HKBCF to Airport Tunnel East (Cut & Cover
Tunnel)
|
Portion X
|
Sheet
Piling Works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel)
|
Portion X
|
Socket
H-Piling Works for HKBCF to Airport Tunnel East (Cut &Cover Tunnel)
|
Portion X
|
Pipe
piling works for HKBCF to Airport Tunnel East (Cut & Cover Tunnel)
|
Portion X
|
Pipe
piling works for Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X & Y
|
Pre-bored
works for excavation in Scenic Hill Tunnel (Cut & Cover Tunnel)
|
Portion X & Y
|
Superstructure
works for Scenic Hill Tunnel West Portal Ventilation building
|
West Portal
|
Excavation
for Scenic Hill Tunnel
|
West Portal
|
Works for
diversion
|
Kwo Lo Wan Road and Airport Road
|
Utilities
detection
|
Airport Road/ Airport Express Line/ East
Coast Road
|
Establishment
of Site Access
|
Airport Road/ Airport Express Line/ East
Coast Road
|
Canopy
pipe drilling / Box Jacking
underneath Airport Express Line
|
Airport Express Line
|
Excavation
and lateral support works at shaft 3 extension north shaft
|
Kwo Lo Wan Road
|
Pipe
roofing drilling / Mined Tunnel excavation underneath Airport Road
|
Airport Road
|
Excavation
and Lateral Support Works for HKBCF to Airport Tunnel West (Cut & Cover
Tunnel)
|
Airport Road
|
Utility
culvert excavation
|
Portion Y
|
Sub-structure
& superstructure works for Highway Operation and Maintenance Area
Building
|
Portion Y
|
2.1
Summary of
EM&A Requirements
2.1.1
The EM&A programme requires environmental monitoring
of air quality, noise, water quality, dolphin monitoring and mudflat monitoring
as specified in the approved EM&A Manual.
2.1.2
A summary of Impact EM&A requirements is
presented in Table 2.1. The locations of air quality, noise and water quality monitoring
stations are shown as in Figure 2.1. The transect line layout in Northwest
and Northeast Lantau Survey Areas is presented in Figure 2.2.
Table 2.1 Summary
of Impact EM&A Requirements
Environmental
Monitoring
|
Description
|
Monitoring
Station
|
Frequencies
|
Remarks
|
Air Quality
|
1-hr TSP
|
AMS 5 & AMS 6
|
At least 3 times every 6 days
|
While the
highest dust impact was expected.
|
24-hr TSP
|
At least once every 6 days
|
--
|
Noise
|
Leq (30mins),
L10 (30mins) and
L90 (30mins)
|
NMS5
|
At least once per week
|
Daytime on normal weekdays
(0700-1900 hrs).
|
Water Quality
|
¡P Depth
¡P Temperature
¡P Salinity
¡P Dissolved Oxygen
(DO)
¡P Suspended Solids
(SS)
¡P DO Saturation
¡P Turbidity
¡P pH
|
¡P Impact Stations:
IS5, IS(Mf)6, IS7, IS8, IS(Mf)9 & IS10,
¡P Control/Far Field
Stations:
CS2 & CS(Mf)5,
¡P Sensitive Receiver
Stations:
SR3, SR4, SR5, SR10A & SR10B
|
Three times per week
during mid-ebb and mid-flood tides (within ¡Ó 1.75 hour of the predicted time)
|
3
(1 m below water surface,
mid-depth and 1 m above sea bed, except where the water depth is less than 6
m, in which case the mid-depth station may be omitted. Should the water depth be less than 3
m, only the mid-depth station will be monitored).
|
Dolphin
|
Line-transect Methods
|
Northeast Lantau survey
area and Northwest Lantau survey area
|
Twice
per month
|
--
|
Mudflat
|
Horseshoe crabs, seagrass beds, intertidal soft shore communities,
sedimentation rates and water quality
|
San Tau and Tung Chung Bay
|
Once every 3 months
|
--
|
2.2.1
Table 2.2 presents
the Action and Limit Levels for the 1-hour TSP, 24-hour TSP and noise level.
Table 2.2 Action
and Limit Levels for 1-hour TSP, 24-hour TSP and Noise
Environmental Monitoring
|
Parameters
|
Monitoring Station
|
Action Level
|
Limit Level
|
Air
Quality
|
1-hr
TSP
|
AMS
5
|
352 µg/m3
|
500 µg/m3
|
AMS
6
|
360 µg/m3
|
24-hr
TSP
|
AMS
5
|
164 µg/m3
|
260 µg/m3
|
AMS
6
|
173 µg/m3
|
Noise
|
Leq
(30 min)
|
NMS 5
|
When
one documented complaint is received
|
75
dB(A)
|
2.2.2
The Action and
Limit Levels for water quality monitoring are given as in Table 2.3.
Table 2.3 Action
and Limit Levels for Water Quality
Parameter
(unit)
|
Water Depth
|
Action
Level
|
Limit Level
|
Dissolved Oxygen (mg/L)
|
Surface and Middle
|
5.0
|
4.2 except 5 for Fish
Culture Zone
|
Bottom
|
4.7
|
3.6
|
Turbidity (NTU)
|
Depth average
|
27.5 or 120% of upstream
control station¡¦s turbidity at the same tide of the same day;
The action level has been
amended to ¡§27.5 and 120% of upstream control station¡¦s turbidity at the same
tide of the same day¡¨ since 25 March 2013.
|
47.0 or 130% of turbidity
at the upstream control station at the same tide of same day;
The limit level has been
amended to ¡§47.0 and 130% of turbidity at the upstream control station at the
same tide of same day¡¨ since 25 March 2013.
|
Suspended Solid (SS)
(mg/L)
|
Depth average
|
23.5 or 120% of upstream
control station¡¦s SS at the same tide of the same day;
The action level has been
amended to ¡§23.5 and 120% of upstream control station¡¦s SS at the same tide of
the same day¡¨ since 25 March 2013.
|
34.4 or 130% of SS at the
upstream control station at the same tide of same day and 10mg/L for Water
Services Department Seawater Intakes;
The limit level has been
amended to ¡§34.4 and 130% of SS at the upstream control station at the same
tide of same day and 10mg/L for Water Services Department Seawater Intakes¡¨
since 25 March 2013
|
Notes:
(1) Depth-averaged is
calculated by taking the arithmetic means of reading of all three depths.
(2) For DO, non-compliance
of the water quality limit occurs when monitoring result is lower that the
limit.
(3) For SS & turbidity
non-compliance of the water quality limits occur when monitoring result is
higher than the limits.
(4) The change to the
Action and limit Levels for Water Quality Monitoring for the EM&A works was
approved by EPD on 25 March 2013. Therefore, the amended Action and Limit
Levels are applied for the water monitoring results obtained on and after 25
March 2013.
2.2.3
The Action and
Limit Levels for dolphin monitoring are shown in Tables 2.4 and 2.5.
Table 2.4 Action
and Limit Level for Dolphin Impact Monitoring
|
North Lantau
Social Cluster
|
NEL
|
NWL
|
Action Level
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
Limit Level
|
STG < 40% of baseline
&
ANI < 40% of baseline
|
Remarks:
(1)
STG
means quarterly average encounter rate of number of dolphin sightings.
(2)
ANI
means quarterly average encounter rate of total number of dolphins.
(3)
For
North Lantau Social Cluster, AL will be 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 all observations identified in environmental site
inspections undertaken during the reporting period. Details of site audit
findings and the corrective actions during the reporting period are presented
in Appendix
F.
3.1.2
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 Obtained During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
March
2016
|
AMS5
|
169
|
117 ¡V 232
|
352
|
500
|
AMS6
|
160
|
107 - 285
|
360
|
April
2016
|
AMS5
|
140
|
90 - 233
|
352
|
AMS6
|
140
|
79 - 236
|
360
|
May 2016
|
AMS5
|
116
|
80 - 222
|
352
|
AMS6
|
117
|
86 - 184
|
360
|
Table 3.2 Summary
of 24-hour TSP Monitoring Results Obtained During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
March 2016
|
AMS5
|
48
|
19 - 112
|
164
|
260
|
AMS6
|
61
|
29 - 143
|
173
|
April 2016
|
AMS5
|
46
|
26 - 82
|
164
|
AMS6
|
59
|
36 - 89
|
173
|
May 2016
|
AMS5
|
39
|
21 - 60
|
164
|
AMS6
|
58
|
32 - 88
|
173
|
3.2.2
There were no Action and
Limit Level exceedances of 1-hr TSP and 24-hr TSP were recorded at AMS5 and
AMS6 during the reporting period.
3.3
Noise Monitoring Results
3.3.1
The monitoring results for construction noise
are summarized in Table 3.3 and the
monitoring results and relevant graphical plots for this reporting
period are provided in Appendix H.
Table 3.3 Summary of Construction Noise
Monitoring Results Obtained During the Reporting Period
Reporting period
|
Monitoring Station
|
Average Leq (30 mins),
dB(A)*
|
Range of Leq (30
mins), dB(A)*
|
Action Level
|
Limit Level Leq (30
mins), dB(A)
|
March 2016
|
NMS5
|
60
|
57 - 73
|
When one documented complaint is received
|
75
|
April 2016
|
61
|
60 - 63
|
May 2016
|
62
|
58 - 67
|
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.
3.4.1
For marine water quality
monitoring, no Action Level and Limit
Level exceedances of turbidity level, dissolved oxygen level and suspended
solid level were recorded during the reporting period.
3.4.2
Water quality impact sources during the water
quality monitoring were the construction activities of the Contract, nearby construction
activities by other parties and nearby operating vessels by other parties.
Data
Analysis
3.5.1 Distribution
Analysis ¡V The line-transect survey data was integrated with the Geographic
Information System (GIS) in order to visualize and interpret different spatial
and temporal patterns of dolphin distribution using sighting positions. Location data of dolphin groups were
plotted on map layers of Hong Kong using a desktop GIS (ArcView© 3.1) to
examine their distribution patterns in details. The dataset was also stratified into
different subsets to examine distribution patterns of dolphin groups with
different categories of group sizes, young calves and activities.
3.5.2 Encounter
rate analysis ¡V Encounter rates of Chinese White Dolphins (number of on-effort
sightings per 100 km of survey effort, and total number of dolphins sighted
on-effort per 100 km of survey effort) were calculated in NEL and NWL survey
areas in relation to the amount of survey effort conducted during each month of
monitoring survey. Dolphin encounter rates were calculated in two ways for
comparisons with the HZMB baseline monitoring results as well as to AFCD
long-term marine mammal monitoring results.
3.5.3 Firstly,
for the comparison with the HZMB baseline monitoring results, the encounter
rates were calculated using primary survey effort alone, and only data
collected under Beaufort 3 or below condition would be used for encounter rate
analysis. The average encounter rate
of sightings (STG) and average encounter rate of dolphins (ANI) were deduced
based on the encounter rates from six events during the present quarter (i.e.
six sets of line-transect surveys in North Lantau), which was also compared
with the one deduced from the six events during the baseline period (i.e. six
sets of line-transect surveys in North Lantau).
3.5.4 Secondly,
the encounter rates were calculated using both primary and secondary survey
effort collected under Beaufort 3 or below condition as in AFCD long-term
monitoring study. The encounter rate
of sightings and dolphins were deduced by dividing the total number of
on-effort sightings and total number of dolphins (ANI) by the amount of survey
effort for the present quarterly period.
3.5.5 Quantitative
grid analysis on habitat use ¡V To conduct quantitative grid analysis of habitat
use, positions of on-effort sightings of Chinese White Dolphins collected
during the quarterly impact phase monitoring period were plotted onto 1-km2
grids among Northwest Lantau (NWL) and Northeast (NEL) survey areas on GIS. Sighting densities (number of on-effort
sightings per km2) and dolphin densities (total number of dolphins
from on-effort sightings per km2) were then calculated for each 1 km
by 1 km grid with the aid of GIS.
Sighting density grids and dolphin density grids were then further
normalized with the amount of survey effort conducted within each grid. The total amount of survey effort spent
on each grid was calculated by examining the survey coverage on each line-transect
survey to determine how many times the grid was surveyed during the study
period. For example, when the
survey boat traversed through a specific grid 50 times, 50 units of survey
effort were counted for that grid.
With the amount of survey effort calculated for each grid, the sighting
density and dolphin density of each grid were then normalized (i.e. divided by
the unit of survey effort).
3.5.6 The
newly-derived unit for sighting density was termed SPSE, representing the
number of on-effort sightings per 100 units of survey effort. In addition, the derived unit for actual
dolphin density was termed DPSE, representing the number of dolphins per 100
units of survey effort. Among the
1-km2 grids that were partially covered by land, the percentage of
sea area was calculated using GIS tools, and their SPSE and DPSE values were
adjusted accordingly. The following
formulae were used to estimate SPSE and DPSE in each 1-km2 grid
within the study area:
SPSE = ((S / E) x 100) /
SA%
DPSE = ((D / E) x 100) /
SA%
where S =
total number of on-effort sightings
D = total number of
dolphins from on-effort sightings
E = total number of units
of survey effort
SA% = percentage of sea
area
3.5.7 Behavioural
analysis ¡V When dolphins were sighted during vessel surveys, their behaviour
was observed. Different activities
were categorized (i.e. feeding, milling/resting, traveling, socializing) and
recorded on sighting datasheets.
This data was then input into a separate database with sighting
information, which can be used to determine the distribution of behavioural
data with a desktop GIS.
Distribution of sightings of dolphins engaged in different activities
and behaviours would then be plotted on GIS and carefully examined to identify
important areas for different activities of the dolphins.
3.5.8 Ranging
pattern analysis ¡V Location data of individual dolphins that occurred during
the 3-month baseline monitoring period were obtained from the dolphin sighting
database and photo-identification catalogue. To deduce home ranges for individual
dolphins using the fixed kernel methods, the program Animal Movement Analyst
Extension, was loaded as an extension with ArcView© 3.1 along with another
extension Spatial Analyst 2.0.
Using the fixed kernel method, the program calculated kernel density
estimates based on all sighting positions, and provided an active interface to
display kernel density plots. The
kernel estimator then calculated and displayed the overall ranging area at 95%
UD level.
Summary
of Survey Effort and Dolphin Sightings
3.5.9
During the period
of March to May 2016, 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 896.56 km of survey effort was collected, with 90.3% of the total survey effort being conducted under favourable weather
conditions (i.e. Beaufort Sea State 3 or below with good visibility). Among the two areas, 341.16 km and 555.40 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 657.94 km, while the
effort on secondary lines was 238.62 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 March to May 2016, a total of seven groups of 22 Chinese White Dolphins were sighted. A summary table of
the dolphin sightings is shown in Annex II of Appendix J.
3.5.13
For the present quarterly period, four of the seven dolphin sightings were made during
on-effort search, while three of the four on-effort dolphin sightings were made on primary
lines. Moreover, all
dolphin groups were sighted in NWL, but none was sighted at all in NEL. In fact, since
August 2014, only one sighting of a lone dolphin was made in NEL during HKLR03 monitoring surveys.
Distribution
3.5.14 Distribution of dolphin sightings made
during monitoring surveys in March to
May 2016 is shown in Figure 1 of Appendix J. Dolphin sightings made in the present quarter were mostly located to the
north of Lung Kwu Chau, while one sighting each was made to the southwest of
Lung Kwu Chau and at the northeast corner of the airport platform respectively (Figure 1 of Appendix J). Notably, four of the five sightings located to the
north of Lung Kwu Chau were all made on the same survey day.
3.5.15
One dolphin group was sighted near the HKBCF
reclamation site. On the other
hand, all other dolphin sightings were made far away from the HKLR03
reclamation site, as well as along the alignments of Tuen Mun-Chek Lap Kok Link
(TMCLKL) and Hong Kong Link Road (HKLR) (Figure 1 of Appendix J).
3.5.16
Sighting
distribution of dolphins during the present impact phase monitoring period (March to May 2016) was drastically different from the one during the
baseline monitoring period (September to November 2011). In the present quarter, dolphins have disappeared from 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). The nearly complete abandonment of NEL
region by the dolphins has been consistently recorded in the past 13 quarters
of HKLR03 monitoring, which has resulted in zero to extremely low dolphin
encounter rates in this area.
3.5.17
In NWL survey area, dolphin occurrence was also very different between the baseline and
impact phase periods. During the
present impact monitoring period, much fewer dolphins occurred in this survey
area (mostly near Lung Kwu Chau) than during the baseline period, when many
dolphin groups were frequently sighted 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).
3.5.18
Another comparison in dolphin distribution was made
between the four quarterly periods of spring months in 2013-16 (Figure 2 of Appendix J). Among the four spring periods, dolphins were
regularly sighted throughout the North Lantau
region in 2013, but their usage there have been significantly reduced to a very
low level in 2015 and 2016 (Figure
2 of Appendix
J).
Encounter Rate
3.5.19 During
the present three-month study period, the encounter rates of Chinese White
Dolphins deduced from the survey effort and on-effort sighting data from the
primary transect lines under favourable conditions (Beaufort 3 or below) for
each set of the surveys in NEL and NWL are shown in Table 3.4. The
average encounter rates deduced from the six sets of surveys were also compared
with the ones deduced from the baseline monitoring period (September ¡V November
2011) (See Table
3.5).
Table
3.4 Dolphin
Encounter Rates (Sightings Per 100 km of Survey Effort) During Reporting Period
(March to May 2016)
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 (7 & 11 Mar 2016)
|
0.00
|
0.00
|
Set 2 (22 & 23 Mar 2016)
|
0.00
|
0.00
|
Set 3 (5 & 12 Apr
2016)
|
0.00
|
0.00
|
Set 4 (15 & 19 Apr 2016)
|
0.00
|
0.00
|
Set 5 (3
& 12 May
2016)
|
0.00
|
0.00
|
Set 6 (17 & 26 May 2016)
|
0.00
|
0.00
|
Northwest Lantau
|
Set 1 (7 & 11 Mar 2016)
|
0.00
|
0.00
|
Set 2 (22 & 23 Mar 2016)
|
1.59
|
4.78
|
Set 3 (5 & 12 Apr
2016)
|
2.20
|
17.59
|
Set 4 (15 & 19 Apr 2016)
|
2.10
|
6.31
|
Set 5 (3
& 12 May
2016)
|
0.00
|
0.00
|
Set 6 (17 & 26 May 2016)
|
0.00
|
0.00
|
Table
3.5 Comparison of average dolphin encounter rates from impact
monitoring period (March to May 2016) and baseline monitoring period (September
¡V November 2011)
Survey Area
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
Reporting Period
|
Baseline Monitoring Period
|
Reporting Period
|
Baseline Monitoring Period
|
Northeast Lantau
|
0.0
|
6.00 ¡Ó 5.05
|
0.0
|
22.19 ¡Ó 26.81
|
Northwest Lantau
|
0.98 ¡Ó
1.10
|
9.85 ¡Ó 5.85
|
4.78 ¡Ó 6.85
|
44.66 ¡Ó 29.85
|
Notes:
1) The encounter rates deduced from the baseline monitoring period have been
recalculated based only on the survey effort and on-effort sighting data made
along the primary transect lines under favourable conditions.
2) ¡Ó denotes the standard deviation of the average
encounter rates.
3.5.20
To
facilitate the comparison with the AFCD long-term monitoring results, the
encounter rates were also calculated for the present quarter using both primary
and secondary survey effort. The
encounter rates of sightings (STG) and dolphins (ANI) in NWL were 0.83
sightings and 3.54 dolphins per 100 km of survey effort respectively, while the
encounter rates of sightings (STG) and dolphins (ANI) in NEL were both nil for
this quarter.
3.5.21
In NEL,
the average dolphin encounter rates (both STG and ANI in the present
three-month impact monitoring period were both zero with no sighting being
made, and such extremely low occurrence of dolphins in NEL have been
consistently recorded in the past thirteen quarters of HKLR03 monitoring (Table 3.6). This is a serious concern
as the dolphin occurrence in NEL in the past few years (0.0-1.0 for ER(STG) and
0.0-3.9 for ER(ANI)) have been exceptionally low when compared to the baseline
period (Table 3.6). Dolphins have been virtually absent from
NEL waters since January 2014, with only two groups of five dolphins sighted
there since then despite consistent and intensive survey effort being conducted
in this survey area.
Table
3.6 Comparison of Average
Dolphin Encounter Rates in Northeast Lantau Survey Area from All Quarters of
Impact Monitoring Period and Baseline Monitoring Period (Sep ¡V Nov 2011)
Monitoring Period
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
September-November 2011 (Baseline)
|
6.00 ¡Ó 5.05
|
22.19 ¡Ó 26.81
|
December 2012-February
2013 (Impact)
|
3.14
¡Ó 3.21
|
6.33
¡Ó 8.64
|
March-May 2013 (Impact)
|
0.42 ¡Ó 1.03*
|
0.42 ¡Ó 1.03*
|
June-August
2013 (Impact)
|
0.88
¡Ó 1.36
|
3.91
¡Ó 8.36
|
September-November
2013 (Impact)
|
1.01
¡Ó 1.59
|
3.77
¡Ó 6.49
|
December 2013-February
2014 (Impact)
|
0.45
¡Ó 1.10
|
1.34
¡Ó 3.29
|
March-May 2014 (Impact)
|
0.00*
|
0.00*
|
June-August
2014 (Impact)
|
0.42
¡Ó 1.04
|
1.69
¡Ó 4.15
|
September-November
2014 (Impact)
|
0.00
|
0.00
|
December 2014-February
2015 (Impact)
|
0.00
|
0.00
|
March-May 2015 (Impact)
|
0.00*
|
0.00*
|
June-August
2015 (Impact)
|
0.44
¡Ó 1.08
|
0.44
¡Ó 1.08
|
September-November
2015 (Impact)
|
0.00
|
0.00
|
December 2015-February
2016 (Impact)
|
0.00
|
0.00
|
March-May 2016 (Impact)
|
0.00*
|
0.00*
|
Notes:
1) The encounter rates
deduced from the baseline monitoring period have been recalculated based only
on survey effort and on-effort sighting data made along the primary transect
lines under favourable conditions.
2) ¡Ó denotes the standard
deviation of the average encounter rates.
3) The encounter rates in
spring months were in blue and marked with asterisk.
3.5.22
On the
other hand, the average dolphin encounter rates (STG and ANI) in NWL during the
present impact phase monitoring period (reductions of 90.1% and 89.3%
respectively) were only small fractions of the ones recorded during the
three-month baseline period, indicating a dramatic decline in dolphin usage of
this survey area as well during the present impact phase period (Table 3.7).
3.5.23
During
the same spring quarters, the dolphin encounter rates in NWL during the spring
months of 2015 and 2016 were much lower than the ones recorded in spring months
of 2013 and 2014 (Table 3.7). Such temporal trend should be closely
monitored in the upcoming monitoring quarters.
3.5.24
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 the past few years.
Table
3.7 Comparison of
Average Dolphin Encounter Rates in Northwest Lantau Survey Area from All
Quarters of Impact Monitoring Period and Baseline Monitoring Period (Sep ¡V Nov
2011)
Monitoring Period
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per
100 km of survey effort)
|
Encounter rate (ANI)
(no.
of dolphins from all on-effort sightings per 100 km of survey effort)
|
September-November 2011 (Baseline)
|
9.85 ¡Ó 5.85
|
44.66 ¡Ó 29.85
|
December 2012-February
2013 (Impact)
|
8.36 ¡Ó 5.03
|
35.90 ¡Ó 23.10
|
March-May 2013 (Impact)
|
7.75 ¡Ó 3.96*
|
24.23 ¡Ó 18.05*
|
June-August
2013 (Impact)
|
6.56 ¡Ó 3.68
|
27.00 ¡Ó 18.71
|
September-November 2013 (Impact)
|
8.04 ¡Ó 1.10
|
32.48 ¡Ó 26.51
|
December 2013-February
2014 (Impact)
|
8.21 ¡Ó 2.21
|
32.58 ¡Ó 11.21
|
March-May 2014 (Impact)
|
6.51 ¡Ó 3.34*
|
19.14 ¡Ó 7.19*
|
June-August 2014 (Impact)
|
4.74
¡Ó 3.84
|
17.52 ¡Ó 15.12
|
September-November 2014 (Impact)
|
5.10
¡Ó 4.40
|
20.52
¡Ó 15.10
|
December 2014-February
2015 (Impact)
|
2.91
¡Ó 2.69
|
11.27
¡Ó 15.19
|
March-May 2015 (Impact)
|
0.47 ¡Ó 0.73*
|
2.36 ¡Ó 4.07*
|
June-August 2015 (Impact)
|
2.53
¡Ó 3.20
|
9.21
¡Ó 11.57
|
September-November 2015 (Impact)
|
3.94
¡Ó 1.57
|
21.05
¡Ó 17.19
|
December 2015-February
2016 (Impact)
|
2.64
¡Ó 1.52
|
10.98
¡Ó 3.81
|
March-May 2016 (Impact)
|
0.98 ¡Ó 1.10*
|
4.78 ¡Ó 6.85*
|
Notes:
1) The encounter rates deduced from the
baseline monitoring period have been recalculated based only on survey effort
and on-effort sighting data made along the primary transect lines under
favourable conditions.
2) ¡Ó denotes the standard deviation of the average encounter rates.
3) The
encounter rates in spring months were in blue and marked with asterisk.
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 (fourteenth
quarter of the impact phase being assessed), the p-values for the differences
in average dolphin encounter rates of STG and ANI were 0.0019 and 0.0173
respectively. If the alpha value is
set at 0.05, significant differences were detected between the baseline and
present quarters in both the average dolphin encounter rates of STG and ANI.
3.5.27 For comparison
between the baseline period and the cumulative quarters in impact phase (i.e.
first fourteen quarters of the impact phase being assessed), the p-values for
the differences in average dolphin encounter rates of STG and ANI were 0.000019
and 0.000005 respectively. Even if
the alpha value is set at 0.00005, significant differences were still detected
in both the average dolphin encounter rates of STG and ANI (i.e. between the
two periods and the locations).
3.5.28 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 construction schedule of the HZMB-related
projects (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 March
to May 2016. 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 (Mar 2016 ¡V May 2016)
and Baseline Monitoring Period (Sep ¡V Nov 2011)
Survey Area
|
Average
Dolphin Group Size
|
Reporting
Period
|
Baseline
Monitoring Period
|
Overall
|
3.14 ¡Ó 2.27 (n = 7)
|
3.72 ¡Ó 3.13 (n = 66)
|
Northeast Lantau
|
N/A
|
3.18 ¡Ó 2.16 (n = 17)
|
Northwest Lantau
|
3.14
¡Ó 2.27 (n = 7)
|
3.92 ¡Ó 3.40 (n = 49)
|
Note:
1) ¡Ó denotes the standard deviation of the
average group size.
3.5.31
The average dolphin group size in NWL waters during
March to May 2016 was slightly lower than the ones recorded during the
three-month baseline period (Table 3.8). All
except one dolphin groups were composed of 1-3 individuals only, while only one
group was moderately large with eight individuals.
3.5.32
Distribution
of the lone larger dolphin group (i.e. 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 spring months of 2016, the only larger dolphin group was sighted to the
southwest of Lung Kwu Chau (Figure 3 of Appendix J). Such
distribution pattern was very different from the baseline period, when the
larger dolphin groups were more frequently sighted and more evenly distributed
in NWL waters, with a few more sighted in NEL waters (Figure 3
of Appendix J).
Habitat Use
3.5.33
From March to
May 2016, the only area being utilized by Chinese White Dolphins was to the north and southwest of Lung Kwu Chau (Figures 4a
and 4b of Appendix J). All grids near HKLR03/HKBCF reclamation sites as
well as HKLR09/ TMCLKL alignments did not record any presence of dolphins at
all during on-effort search in the present quarterly period (Figures 4b of
Appendix J).
3.5.34 It should be emphasized though that the amount of survey effort collected in each
grid during the three-month period was fairly low (6-12 units of survey effort
for most grids), and therefore the habitat use pattern derived from the
three-month dataset should be treated with caution. A more complete picture of dolphin
habitat use pattern should be
examined when more
survey effort for each grid will be collected throughout the impact phase
monitoring programme.
3.5.35
When compared with the habitat use patterns during
the baseline period, dolphin usage in NEL and NWL has drastically diminished in
both areas during the present impact monitoring period (Figure 5 of Appendix J). During the baseline period, many grids between Siu Mo
To and Shum Shui Kok in NEL recorded moderately high to high dolphin densities,
which was in stark contrast to the complete absence of dolphins there during
the present impact phase period (Figure 5 of Appendix J).
3.5.36
The density patterns were also very different in
NWL between the baseline and impact phase monitoring periods, with higher
dolphin usage throughout the area, especially 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, the only area with moderate to high dolphin densities was
restricted to the waters near Lung Kwu Chau during the present impact phase
period (Figure 5 of Appendix J).
Mother-calf Pairs
3.5.37
During the present quarterly period, neither unspotted
calf nor unspotted juvenile was sighted with any female in the North Lantau
region.
3.5.38
The absence of young calves in the present quarter
was in stark contrast to their regular occurrence in North Lantau waters during
the baseline period. This should be
of a serious concern, and the occurrence of young calves in North Lantau waters
should be closely monitored in the upcoming quarters.
Activities and Associations with Fishing Boats
3.5.39
Only one of the seven dolphin groups were engaged
in feeding activity, while none of them was engaged in socializing, traveling or milling/resting activity during the three-month study period.
3.5.40
The percentage of sightings associated with feeding
activities (14.3%) was similar to the one recorded during the baseline period
(11.6%). However, it should be
noted the sample sizes on total numbers of dolphin sightings during the present
quarter (seven dolphin groups) was much lower than the baseline period (66
dolphin groups).
3.5.41
Distribution of dolphins engaged in various activities during the present
impact phase period and the baseline period is shown in Figure 6 of
Appendix J.
The only
dolphin group engaged in feeding activity was sighted to the north of Lung Kwu
Chau during the present quarterly period, which was very different from the
baseline period when various dolphin activities occurred throughout the North
Lantau region (Figure 6 of Appendix J).
3.5.42
As consistently recorded in the past monitoring
quarters, none of the seven dolphin groups was found to be associated with any operating fishing vessel in North Lantau waters during the
present impact phase period.
Summary Photo-identification works
3.5.43
From March
to May 2016, over 800 digital photographs of Chinese
White Dolphins were taken during the impact phase monitoring surveys for the
photo-identification work.
3.5.44
In total, 16
individuals sighted 18 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.
3.5.45
The majority of identified
individuals were sighted only once during the three-month period, with the
exception of two individuals (NL48 and NL285) being sighted twice in the present quarter.
3.5.46
Notably,
two of these 16 individuals (NL123 and NL320) were also sighted in West Lantau waters during the HKLR09 monitoring surveys
from March to May 2016.
Individual range use
3.5.47
Ranging patterns of the 16
individuals identified during the three-month study period were determined by
fixed kernel method, and are shown in Annex V of Appendix J.
3.5.48
All identified dolphins sighted in the present
quarter were utilizing NWL waters only, but have completely avoided 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 the baseline period.
3.5.49
On the
other hand, two individuals (NL123 and NL320) consistently utilized both North Lantau waters in the past have extended their range
use to WL waters during the present quarter. In the upcoming quarters, 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 (see Hung 2015).
3.5.50
There was one Limit Level
exceedance of dolphin monitoring for the quarterly monitoring data (between
March 2016 ¡V May 2016). According to the contractor¡¦s information, the marine
activities undertaken for HKLR03 during the quarter of March 2016 ¡V May 2016
included removal of surcharge materials, temporary drainage diversion, ground
investigation and maintenance of silt curtain.
3.5.51
There is no evidence
showing the current LL non-compliance directly related to the construction
works of HKLR03 (where the amounts of working vessels for HKLR03 have been
decreasing), although the generally increased amount of vessel traffic in NEL
during the impact phase has been partly contributed by HKLR03 works since
October 2012. It should also be noted that 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 (CWD). In addition, the contractor will implement
proactive mitigation measures such as avoiding anchoring at Marine Department¡¦s
designated anchorage site ¡V Sham Shui Kok Anchorage (near Brothers Island) as
far as practicable.
3.5.52
According to Monitoring
of Chinese White Dolphins in Southwest Lantau Waters ¡V Fourth Quarterly Report
(December 2015 to February 2016) which is available on ENPO¡¦s website, with
their primary ranges centered in North and West Lantau waters, some individuals
showed apparent range shifts or extensions to Southwest Lantau waters in
2015-16. For example, three
individual dolphins (NL120, WL46 and WL221) indicated obvious shifts in their
range use from NWL to West Lantau (WL) and Southwest Lantau (SWL) waters.
Moreover, many individuals (e.g. NL212, NL260, WL200, SL55, WL232, WL237 and
WL265) have extended their ranges from WL waters to SWL waters. It remains to be seen whether some of
these individuals have permanently shifted their ranges away from their primary
ranges in North Lantau, or begin to spend more times in SWL waters as part of
their ranges.
3.5.53 ENPO updated that the Hong Kong-Zhuhai-Macao Bridge Authority (HZMBA) for
the Mainland section of Hong Kong-Zhuhai-Macao Bridge (HZMB) has commenced an
interim survey on fisheries resources and CWD in the Mainland waters. ENPO
presented the preliminary findings of the HZMBA interim survey on CWD sighting
and photo-identification works which provide solid evidence that some CWD that
were previously more often sighted in HK waters have expanded their ranges into
the Mainland waters, and some with reduced usage in HK waters. These
preliminary data were mentioned in Monitoring of Chinese White Dolphins in
Southwest Lantau Waters ¡V Fourth Quarterly Report (December 2015 to February
2016) which is available on ENPO¡¦s website.
3.5.54
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).
3.5.55
For the comparison
between the baseline period and the present quarter (fourteenth quarter of the
impact phase being assessed), the p-values for the differences in average
dolphin encounter rates of STG and ANI were 0.0019 and 0.0173
respectively. If the alpha value is
set at 0.05, significant differences were detected between the baseline and
present quarters in both the average dolphin encounter rates of STG and ANI.
3.5.56
For comparison between
the baseline period and the cumulative quarters in impact phase (i.e. first
fourteen quarters of the impact phase being assessed), the p-values for the
differences in average dolphin encounter rates of STG and ANI were 0.000019 and
0.000005 respectively. Even if the
alpha value is set at 0.00005, significant differences were still detected in
both the average dolphin encounter rates of STG and ANI (i.e. between the two
periods and the locations).
3.5.57
The AFCD monitoring data
during March to May 2016 has been reviewed by the dolphin specialist. During the same quarter, no dolphin was
sighted from 159.50 km of survey effort on primary lines in NEL, while two
groups of two dolphins were sighted from 186.34 km of survey effort on primary
lines in NWL. This review has
confirmed that the extremely low occurrence of dolphins reported by the HKLR03
monitoring surveys in spring 2016 in NEL and NWL survey area is accurate.
3.5.58
All dolphin protective
measures are fully and properly implemented in accordance with the EM&A
Manual. According to the Marine Travel Route Plan, the travelling speed of
vessels must not exceed 5 knots when crossing the edge of the proposed marine
park. The Contractor will continue to provide training for skippers to ensure
that their working vessels travel from source to destination to minimize
impacts on Chinese White Dolphin and avoid anchoring at Marine Department¡¦s
designated anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as
far as practicable. Also, it is recommended to complete the marine works of the
Contract as soon as possible so as to reduce the overall duration of impacts
and allow the dolphins population to recover as early as possible.
3.5.59
All dolphin protective
measures are fully and properly implemented in accordance with the EM&A
Manual. According to the Marine Travel Route Plan, the travelling speed of
vessels must not exceed 5 knots when crossing the edge of the proposed marine
park. The Contractor will continue to provide training for skippers to ensure
that their working vessels travel from source to destination to minimize
impacts on Chinese White Dolphin and avoid anchoring at Marine Department¡¦s
designated anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as
far as practicable. Also, it is recommended to complete the marine works of the
Contract as soon as possible so as to reduce the overall duration of impacts
and allow the dolphins population to recover as early as possible.
3.5.60
A meeting was held on 22
July 2016 with attendance of representative of Highways Department (HyD), 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/2012/08 attended the meeting. The
discussion/recommendation as recorded in the minutes of the meeting, which
might be relevant to HKLR03 Contract are summarized below.
3.5.61
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.
3.5.62
The dolphin specialists
of the projects confirmed that the CWD sighting around the North of Sha Chau
and Lung Kwu Chau Marine Park (SCLKCMP) has significantly decreased, and it was
apparently related to the re-routing of high speed ferry (HSF) from Skypier.
3.5.63
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.
3.5.64
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.
3.5.65
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.
3.5.66
It was suggested that the
protection measures (e.g., speed limit control) for the proposed Brothers
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. HyD updated that the draft map of
the proposed BMP was gazetted in February 2016. The ETs were reminded to update
the BMP boundary in the Regular Marine Travel Route Plan.
3.5.67
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 9 March 2016. 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
(March 2016)
|
Monitoring Station
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
810291.160
|
816678.727
|
0.950
|
810291.129
|
816678.735
|
1.135
|
S2
|
810958.272
|
815831.531
|
0.864
|
810958.294
|
815831.517
|
1.007
|
S3
|
810716.585
|
815953.308
|
1.341
|
810716.586
|
815953.341
|
1.487
|
S4
|
811221.433
|
816151.381
|
0.931
|
811221.528
|
816151.433
|
1.176
|
Table 3.10 Comparison
of Measurement
|
Comparison of
measurement
|
Remarks and Recommendation
|
Monitoring Station
|
Easting
(m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
-0.031
|
0.008
|
0.185
|
Level continuously increased
|
S2
|
0.022
|
-0.014
|
0.143
|
Level continuously increased
|
S3
|
0.001
|
0.033
|
0.146
|
Level continuously increased
|
S4
|
0.095
|
0.052
|
0.245
|
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
March 2016. 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)
|
2-Mar-16
|
9.68
|
3.50
|
5.35
|
8.85
|
3.65
|
4.75
|
4-Mar-16
|
10.06
|
2.15
|
3.50
|
11.10
|
2.00
|
3.20
|
7-Mar-16
|
11.39
|
2.85
|
6.00
|
11.64
|
5.30
|
16.60
|
9-Mar-16
|
9.45
|
5.90
|
9.60
|
9.90
|
4.00
|
9.85
|
11-Mar-16
|
8.91
|
4.35
|
6.45
|
8.53
|
3.55
|
3.70
|
14-Mar-16
|
8.60
|
3.10
|
7.80
|
8.73
|
2.75
|
6.70
|
16-Mar-16
|
8.17
|
2.45
|
4.80
|
8.23
|
2.45
|
4.75
|
18-Mar-16
|
8.12
|
2.65
|
4.40
|
7.92
|
3.25
|
4.95
|
21-Mar-16
|
7.88
|
4.35
|
6.65
|
7.99
|
12.10
|
16.95
|
23-Mar-16
|
7.73
|
5.55
|
6.45
|
7.58
|
7.00
|
9.00
|
25-Mar-16
|
7.35
|
3.75
|
4.95
|
7.33
|
3.95
|
8.30
|
28-Mar-16
|
8.28
|
4.55
|
7.40
|
7.79
|
3.75
|
5.65
|
30-Mar-16
|
8.48
|
5.00
|
3.90
|
8.31
|
4.25
|
4.40
|
Average
|
8.77
|
3.86
|
5.94
|
8.76
|
4.46
|
7.60
|
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) (Figure 2.1 of Appendix O). 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
March 2016 (totally 6 sampling days between 8th to 26th March 2016).
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 8th (for TC3), 13th (for TC1), 20th (for TC2), 22nd (for ST) and 26th (second survey for TC1) March 2016. The weather was generally cloudy for all day time surveys (13th-26th Mar) while it was humid during the night time survey
(8th Mar). Since there
was intermittent rain during the survey for TC1 on 13th Mar, the horseshoe crab trail would cease that
searching became difficult. Hence a second
survey was conducted on 26th Mar
under cloudy weather.
Seagrass Beds
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 8th (for TC3), 13th (for TC1), 20th (for TC2) and 22nd (for ST) March 2016. The weather was cloudy
and cold for all day time surveys
(13th-22nd Mar)
while it was humid during the night
time survey (8th Mar).
Intertidal Soft Shore
Communities
3.6.8 The intertidal soft shore community surveys
were conducted in low tide period 8th (for TC3), 12th (for ST), 13th (for TC1) and 20th (for TC2) March 2016. 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.
3.6.9
Inside
a quadrat, any visible
epifauna were collected and were in-situ identified to the lowest
practical taxonomical resolution. Whenever possible a
hand core sample (10 cm internal diameter ´
20 cm depth) of sediments was collected in the quadrat. The core sample was gently washed through a
sieve of mesh size 2.0 mm
in-situ. Any visible infauna were collected
and identified. Finally the top 5 cm surface sediments were
dug for visible infauna in the quadrat regardless of hand core sample was taken.
3.6.10
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.
3.6.11
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
3.6.12 Data
collected from direct search and core sampling was pooled in every quadrat for
data analysis. Shannon-Weaver Diversity Index (H¡¦) and Pielou¡¦s Species
Evenness (J) were calculated for every quadrat using the formulae below,
H¡¦= -£U ( Ni / N ) ln ( Ni / N ) (Shannon and Weaver,
1963)
J = H¡¦ / ln
S, (Pielou, 1966)
where S is the total number of species in the sample,
N is the total number of individuals, and Ni is the number of individuals of
the ith species.
Mudflat
Ecology Monitoring Results and Conclusion
Horseshoe
Crabs
3.6.13
In general, two species of horseshoe crab Carcinoscorpius
rotundicauda (total 23
ind.) and Tachypleus tridentatus (total
17 ind.) were recorded. For one sight record, grouping
of 2-8 individuals was observed
at same locations with similar substratum (fine sand or soft
mud). 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.
3.6.14
Table 3.1
of Appendix O summarizes
the survey results of horseshoe crab in present survey. For Carcinoscorpius rotundicauda,there were 21 and 2 individuals in TC3 and ST
respectively. For TC3, the search record was 3.5 ind. hr-1 person-1 while the average body size was 35.49
mm (prosomal width ranged 25.53-48.12 mm).
For
ST, the search record was 0.3 ind. hr-1 person-1 while the average
body size was 35.70 mm (prosomal width ranged 16.82-54.58 mm). No individual was found in TC1 and TC2.
3.6.15
For Tachypleus tridentatus, there was 17 individuals recorded in TC3 only. The search record
was
2.8 ind. hr-1 person-1 while the average body size was 41.83 mm (prosomal width ranged 26.79-48.91 mm).
3.6.16
In the
previous survey of March 2015, there was one important finding that a mating
pair of Carcinoscorpius rotundicauda was found in ST (prosomal width: male 155.1 mm,
female 138.2 mm) (Figure
3.2 of Appendix 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. In
present survey the records of the two big individuals of Carcinoscorpius
rotundicauda (prosomal width 117.37 mm and 178.17 mm)
were excluded from data analysis according to the same principle.
3.6.17
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.
3.6.18 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
3.6.19
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
June 2014. Then the search record in TC3 was even higher than that in ST from
September 2014 to June 2015. In September 2015, the search records were similar
in TC3 and ST. In March 2016 (present survey), higher search record was noticed
in TC3 again. For TC1, the search record was at low to medium level and the
number of both species could fluctuate along the sampling months. Relatively,
search record was very low in TC2 (2 ind. in Sep. 2013, 1 ind. in Mar., Jun.,
Sep. 2014, Mar. and Jun 2015, 4 ind. in Sep. 2015). For the body size, larger
individuals of Carcinoscorpius rotundicauda
were usually found in ST and TC1 relative to those in TC3. For Tachypleus tridentatus, larger
individuals were also found in ST followed by TC3 and TC1.
3.6.20 Throughout the monitoring period conducted, it was obvious that TC3 and ST
(western shore of Tung Chung Wan) was an important nursery ground for horseshoe
crab especially newly hatched individuals due to larger area of suitable
substratum (fine sand or soft mud) and less human disturbance (far from urban
district). Relatively, other sampling zones were not a suitable nursery ground
especially TC2. Possible factors were less area of suitable substratum
(especially TC1) and higher human disturbance (TC1 and TC2: close to urban
district and easily accessible). In TC2, large daily salinity fluctuation was a
possible factor either since it was flushed by two rivers under tidal
inundation. The individuals inhabiting TC1 and TC2 were confined in small
moving range due to limited area of suitable substrata during the nursery
period.
Seasonal variation of horseshoe crab
population
3.6.21 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). In December 2013, no individual of
horseshoe crab was found. In December 2014, 2 individuals of Carcinoscorpius
rotundicauda and 8 individuals of Tachypleus tridentatus
were found only. In December 2015,
2 individuals of Carcinoscorpius rotundicauda, 6
individuals of Tachypleus
tridentatus and one newly hatched, unidentified
individual were found only. The
horseshoe crabs were inactive and burrowed in the sediments during cold weather
(<15 ºC). Similar results of low search record in dry
season were reported in a previous territory-wide survey of horseshoe crab. For
example, the search records in Tung Chung Wan were 0.17 ind. hr-1
person-1 and 0.00 ind. hr-1 person-1 in wet season and dry season respectively
(details see Li, 2008). After the dry season, the search record increased with
the warmer climate.
3.6.22 Between the sampling months September 2012
and December 2013, Carcinoscorpius
rotundicauda was a less common species relative to Tachypleus tridentatus.
Only 4 individuals were ever recorded in ST in December 2012. This species had
ever been believed of very low density in ST hence the encounter rate was very
low. Since March. 2014, it was found in all sampling zones with higher
abundance in ST. Based on its average size (mean prosomal width 39.28-49.81
mm), it indicated that breeding and spawning of this species had occurred about
3 years ago along the coastline of Tung Chun Wan. However, these individuals
were still small while their walking trails were inconspicuous. Hence there was
no search record in previous sampling months. From March 2014 to September
2015, more individuals were recorded due to larger size and higher activity
(i.e. more conspicuous walking trail).
3.6.23 For Tachypleus tridentatus, sharp increase of number of individuals was recorded in ST with wet
season (from March to September 2013). According to a personal conversation
with Prof. Shin (CityU), his monitoring team had recorded similar increase of
horseshoe crab population during wet season. It was believed that the suitable
ambient temperature increased its conspicuousness. However similar pattern was
not recorded during the wet season of 2014. The number of individuals increased
in March and June 2014 followed by a rapid decline in September 2014. Then the
number of individuals fluctuated in TC3 while it decreased steadily in ST until
September. 2015. Apart from natural mortality, migration from nursery soft
shore to subtidal habitat was another possible cause. Since the mean prosomal
width of Tachypleus tridentatus
continued to grow and reached about 50 mm since March 2014. Then it varied
slightly between 50-65 mm from September 2014 to September 2015. Most of the
individuals might have reached a suitable size strong enough to forage in
sub-tidal habitat.
3.6.24 Since TC3 and ST were regarded as important
nursery ground for horseshoe crab, box plots of prosomal width of two horseshoe
crab species were constructed to investigate the changes of population in
details.
Box plot of horseshoe
crab populations in TC3
3.6.25 Figure 3.5 of Appendix O shows the changes of prosomal width of Carcinoscorpius rotundicauda and Tachypleus tridentatus in
TC3. As mentioned above, Carcinoscorpius
rotundicauda was rarely found between September 2012 and
December 2013 hence the data were lacking. In March 2014, the major size (50% of individual records
between upper and lower quartile) ranged 40-60 mm while only few individuals
were found. From March 2014 to September 2015, the size of major population
decreased and more small individuals were recorded after March of every year. It
indicated new rounds of successful breeding and spawning of Carcinoscorpius rotundicauda in TC3. It
matched with the previous mating record in ST in March 2015.
3.6.26 For
Tachypleus tridentatus, the major size ranged 20-50 mm while the number of
individuals found fluctuated from September 2012 to June 2014. Then a slight
but consistent growing trend was observed. The prosomal width increased from
25-35 mm in September 2014 to 35-65 mm in June 2015. As mentioned, the large
individuals might have reached a suitable size for migrating from the nursery
soft shore to subtidal habitat. It accounted for the declined population in
TC3.
3.6.27 From June
2015 to March 2016 (present survey), slight increasing trends of major size
were noticed for both species. It might be accounted by new round of spawning.
But it was yet to conclude until wet season results (June & September 2016)
were available.
Box plot of horseshoe crab populations in ST
3.6.28
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 Mar. 2014 to Sep. 2015, the size of major population
decreased and more small individuals were recorded after June of every year. It
indicated new rounds of successful breeding and spawning of Carcinoscorpius rotundicauda in ST. It
matched with the previous mating record in ST in March 2015. Because most of
newly hatched individuals (prosomal width ~5mm) would take about half year to
grow to a size with conspicuous walking trail.
3.6.29
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 September 2015, the size of major population decreased slightly to a
prosomal width 40-60 mm. At the same time, the number of individuals decreased
gradually. It further indicated some of large individuals might have migrated
to sub-tidal habitats. In December 2015, two big individuals (prosomal width
89.27 mm and 98.89 mm) were recorded only while it could not represent the
major population.
3.6.30
From
December 2015 to March 2016 (present survey), the number of horseshoe crab recorded
was very few in ST. Hence the population change of both species could not be
determined.
3.6.31
As a
summary for horseshoe crab populations in TC3 and ST, there was successful
spawning of Carcinoscorpius rotundicauda
from 2014 to 2015 while the spawning time should be in spring. There were
consistent, increasing trends of population size in these two sampling zones.
For Tachypleus tridentatus,
small individuals were rarely found TC3 and ST from 2014 to 2015. It was
believed no occurrence of successful spawning. The existing individuals (that
recorded since 2012) grew to a mature size and migrated to sub-tidal habitat.
Hence the number of individuals decreased gradually. It was expected the
population would remain at low level until new round of successful spawning.
Impact of the HKLR project
3.6.32
The
present survey was the 14th survey of the EM&A programme during
the construction period. Based on the results, impact of the HKLR
project could not be detected on horseshoe crabs considering the factor of
natural, seasonal variation. In case, abnormal phenomenon (e.g.
very few numbers of horseshoe crab individuals in wet season,
large number of dead individuals on the shore) is observed, it would be
reported as soon as possible.
Seagrass
Beds
3.6.33
In
general, seagrass
was found in ST only. Two
seagrass species Halophila ovalis and Zostera japonica were recorded. Both species were
found on sandy substratum nearby the seaward side of mangrove vegetation at 2.0
m above C.D. The seagrass bed existed in irregular patches or long strand in
various sizes. For one long strand, two seagrass species were found coexisting
in variable coverage. 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.
3.6.34
Table 3.2 of Appendix O summarize
the results of seagrass beds survey in ST. Eight patches of Halophila ovalis were found
while the total seagrass bed area was about 230.6 m2 (average area 28.8 m2).
The largest patch was a horizontal strand with seagrass bed area 100.4 m2.
It coexisted with another seagrass species and remained at very low coverage (10%).
Other three horizontal strands were at medium size (15.8-41.1 m2)
and high coverage (80-100%). The rest were small patches (1.5-17.3 m2)
and variable coverage (20-90%). For Zostera
japonica, it was mainly found coexisting with Halophila ovalis in the largest strand (100.4
m2) of seagrass bed with high coverage 90%.
3.6.35
Since majority of seagrass bed was confined
in ST, the temporal change of both seagrass species were investigated in
details.
Temporal variation
of seagrass beds
3.6.36 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).
It might be due to the disappearance of the originally dominant seagrass Halophila ovalis
resulting in less competition for substratum and nutrients. From September 2015
to March 2016, it was found coexisting with seagrass Halophila ovalis with steady increasing patch size and
variable coverage.
3.6.37 For Halophila ovalis, it was recorded as 3-4 medium to large
patches (area 18.9 - 251.7 m2; vegetation coverage 50-80%) beside
the mangrove vegetation at tidal level 2 m above C.D in September 2012 (first
survey). The total
seagrass bed area grew steadily from 332.3 m2 in September 2012 to
727.4 m2 in December 2013. Flowers could be observed in the largest
patch during its flowering period in December 2013. In March 2014, 31 small to medium
patches were newly recorded (variable area 1-72 m2 per patch,
vegetation coverage 40-80% per patch) in lower tidal zone between 1.0 and 1.5 m
above C.D. The total seagrass area increased further to 1350 m2. In
June 2014, these small and medium patches grew and extended to each others.
These patches were no longer distinguishable and were covering a significant
mudflat area of ST. It was generally grouped into 4 large areas (1116 ¡V 2443 m2)
of seagrass beds characterized of patchy distribution, variable vegetable
coverage (40-80%) and smaller leaves. The total seagrass bed area increased
sharply to 7629 m2. In September 2014, the total seagrass area
declined sharply to 1111 m2. There were only 3-4 small to large
patches (6 - 253 m2) at high tidal level and 1 patch at low tidal
level (786 m2). Typhoon or strong water
current was a possible cause
(Fong, 1998). In September 2014, there were two tropical cyclone records in
Hong Kong (7th-8th September: no cyclone name, maximum
signal number 1; 14th-17th September: Kalmaegi maximum
signal number 8SE) before the seagrass survey dated 21st September
2014. The strong water current caused by the cyclone, Kalmaegi especially,
might have given damage to the seagrass beds. In addition, natural heat stress
and grazing force were other possible causes reducing seagrass beds area.
Besides, Halophila ovalis could be found in other mud flat area
surrounding the single patch. But it was hardly distinguished into patches due
to very low coverage (10-20%) and small leaves.
3.6.38
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
3.6.39 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.
3.6.40 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).
3.6.41 In order to investigate any deterioration of
water quality (e.g. more turbid) in ST, the water quality measurement results
at two closest monitoring stations SR3 and IS5 of the EM&A programme were
obtained from the water quality monitoring team. Based on the results from June
to December 2014, the overall water quality was in normal fluctuation except
there was one exceedance of suspended solids (SS) at both stations in
September. On 10th September, 2014, the SS concentrations measured
at mid-ebb tide at stations SR3 (27.5 mg/L) and IS5 (34.5 mg/L) exceeded the
Action Level (≤23.5 mg/L and 120% of upstream control station¡¦s reading) and
Limit Level (≤34.4 mg/L and 130% of upstream control station¡¦s reading)
respectively. The turbidity readings at SR3 and IS5 reached 24.8-25.3 NTU and
22.3-22.5 NTU respectively. The temporary turbid water should not be caused by
the runoff from upstream rivers. Because there was no rain or slight rain from
1st to 10th September 2014 (daily total rainfall at the
Hong Kong International Airport: 0-2.1 mm; extracted from the climatological
data of Hong Kong Observatory). The effect of upstream runoff on water quality
should be neglectable in that period. Moreover the exceedance of water quality
was considered unlikely to be related to the contract works of HKLR according
to the ¡¥Notifications of Environmental Quality Limits Exceedances¡¦ provided by
the respective environmental team. The respective construction of seawall and
stone column works, which possibly caused turbid water, were carried out within
silt curtain as recommended in the EIA report. Moreover there was no leakage of
turbid water, abnormity or malpractice recorded during water sampling. In
general, the exceedance of suspended solids concentration was considered to be
attributed to other external factors, rather than the contract works.
3.6.42 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.
Recolonization of
seagrass beds
3.6.43 Figure 3.9 of Appendix O shows the changes of seagrass bed area at ST.
From March to June 2015, 2-3 small patches of Halophila ovalis were newly found
coinhabiting with another seagrass species Zostera japonica. But its total patch area was
still very low relative to the previous records. The recolonization rate was
low while cold weather and insufficient sunlight were possible factors between
December 2014 and March 2015. Moreover, it would need to compete with more
abundant seagrass Zostera japonica for
substratum and nutrient. Since Zostera
japonica had
extended and had covered the original seagrass bed of Halophila ovalis at
certain degree. From June to March 2016, the total seagrass area of Halophila ovalis had increased rapidly
from 6.8 m2 to 230.63 m2. It had recolonized its original
patch locations and covered Zostera japonica.
Hence it was expected that the seagrass bed of Halophila ovalis would increase continually in the following
months.
Impact of the HKLR project
3.6.44 The present survey was the 14th survey
of the EM&A programme during the construction period. According to the
results of present survey, there was recolonization of both seagrass
species Halophila ovalis and Zostera japonica in
ST. The seagrass patches were believed in recovery. Hence the negative impact of HKLR project on
the seagrass was not significant. In case, adverse phenomenon (e.g.
reduction of seagrass patch size, abnormal change of leave colour) is
observed again, it would be reported as soon as possible.
Intertidal
Soft Shore Communities
3.6.45
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
zones:
¡P In TC1, high percentage of ¡¥Gravels and
Boulders¡¦ (80-90%) was recorded at high and mid tidal levels. ¡¥Gravels and
Boulders¡¦ (60%) and ¡¥Sands¡¦ (30%) were the major substratum types at low tidal
level.
¡P In TC2, high percentage of ¡¥Soft mud¡¦ (80%)
was recorded at all tidal levels.
¡P In TC3, the substratum type was clearly
different between high-mid tidal level and low tidal level. ¡¥Sands¡¦ (50-60%)
and ¡¥Soft mud¡¦ (40-50%) were the major substratum types at high and mid tidal
levels. High percentage of ¡¥Gravels and Boulders¡¦ (90%) was recorded at low
tidal level.
¡P In ST, the substratum type was clearly
different between high-mid tidal level and low tidal level. ¡¥Gravels and
Boulders¡¦ (100%) was the only substratum type at high and mid tidal levels. At
low tidal level, higher percentage of ¡¥Soft mud¡¦ (80%) was recorded followed by
¡¥Gravels and Boulders¡¦ (20%).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.
3.6.46
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.
3.6.47
Table 3.4 of Appendix O lists the total
abundance, density and number of taxon of
every phylum in this survey. A total of
11728 individuals were recorded. Mollusca was
significantly the most abundant phylum (total individuals 11496,
density 383 ind. m-2, relative abundance 98.0%).
The second abundant phylum was Arthropoda
(127 ind., 4 ind. m-2, 1.1%). The
less abundant phyla were Annelida (62
ind., 2 ind. m-2, 0.5%) and
Cnidaria (17 ind., 1
ind. m-2, 0.1%). Relatively other phyla were very low in abundances
(density £1
ind. m-2, relative abundance £0.1%).
Moreover, the most diverse phylum was Mollusca
(37 taxa) followed by Arthropoda
(11 taxa) and Annelida (10 taxa). There was 1 taxon
recorded only for other phyla. The taxonomic resolution
and complete list of collected specimens are shown
in Annex IV and V of Appendix O.
3.6.48
Table 3.5 of Appendix O shows the number of individual, relative
abundance and density of each phylum in every
sampling zone. The total abundance (2313-4085 ind.) varied
among the four sampling zones while the phyla distributions
were similar. In general, Mollusca was
the most dominant phylum (no. of individuals: 2213-4054
ind.; relative abundance 95.7-99.2%;
density 295-541 ind. m-2). Other phyla were significantly
lower in number of individuals. Arthropoda
was the second abundant phylum (15-68
ind.; 0.4-2.9%;
2-9 ind. m-2). Annelida was the third
abundant phylum in TC1, TC2 and TC3 (7-26 ind.; 0.2-1.1%; 1-3 ind. m-2)
while it was the fourth abundant in ST (8 ind.; 0.3%; 1 ind. m-2).
Cnidaria (sea anemone) was the third abundant phylum (15 ind.;
0.6%; 2 ind. m-2) in ST. Relatively
other phyla were low in abundance in all sampling zones (≤
0.1%)
Dominant
species in every sampling zone
3.6.49 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 species of very high density (620 ind. m-2, relative abundance
84%) at high tidal level (major substratum: ¡¥Gravels and Boulders¡¦). At mid
tidal level (major substratum: ¡¥Gravels and Boulders¡¦), gastropod Batillaria
multiformis was also the most abundant species of high density (214 ind. m-2, relative abundance
47%) followed by
gastropod Monodonta labio
(81 ind. m-2, 18%) and rock oyster Saccostrea
cucullata (70 ind. m-2, 16%, attached on
boulders) at moderate
densities. At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata was the most abundant species of moderate-high
density (141
ind. m-2, 32%) followed by gastropods Monodonta labio (98 ind. m-2,
22%), Batillaria
zonalis (51
ind. m-2, 11%) and Batillaria multiformis (47 ind. m-2, 10%) at moderate densities.
3.6.50 At
TC2, gastropod Cerithidea
djadjariensis (123 ind.
m-2, 32%) was the most abundant at
moderate density followed by gastropods Batillaria multiformis (69 ind. m-2,
18%) Cerithidea cingulata (41 ind. m-2, 11%) and rock oyster Saccostrea
cucullata (67 ind. m-2, 17%) at high tidal level (major substratum: ¡¥Soft mud¡¦). At mid and low tidal levels (major substrata: ¡¥Soft
mud¡¦), rock oyster Saccostrea cucullata (102-103 ind. m-2, 32-45%) was the most abundant followed by gastropod Batillaria zonalis (48-95 ind. m-2,
22-30%). Besides,
gastropod Cerithidea djadjariensis (34 ind. m-2, 11%) was the third abundant at mid tidal level.
3.6.51 At TC3, the abundant species were quite different
between three tidal levels. At high tidal level (major substratum: ¡¥Sands¡¦), gastropod Batillaria
multiformis was the most abundant species of high density (268 ind. m-2,
59%) followed by gastropod Cerithidea djadjariensis (123 ind. m-2,
27%). At mid tidal
level (major substratum: ¡¥Sands¡¦), the abundant species were at moderate
densities including gastropods
Cerithidea djadjariensis (86 ind. m-2, 32%), Cerithidea cingulata (55
ind. m-2, 21%), Batillaria multiformis (51 ind. m-2, 19%) and Batillaria zonalis (46 ind. m-2,
17%). At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), the abundant species were at moderate densities including rock oyster Saccostrea cucullata (143
ind. m-2, 31%), gastropods Monodonta labio (127 ind. m-2,
27%) and Batillaria
multiformis (125
ind. m-2, 27%).
3.6.52 At
ST, gastropod gastropods Monodonta
labio (166 ind. m-2,
42%) and Batillaria
multiformis (120
ind. m-2, 31%) were of moderate densities followed by rock oyster Saccostrea cucullata (48
ind. m-2, 12%) at high tidal level (major substratum: ¡¥Gravels and Boulders¡¦). At mid
tidal level (major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata (176
ind. m-2, 39%) and gastropod Monodonta labio (120 ind.
m-2, 26%) became abundant followed by gastropod Lunella coronata (61 ind. m-2,
13%). At low tidal
level (major substratum: ¡¥Soft mud¡¦), rock oyster Saccostrea cucullata (34
ind. m-2, 38%) and gastropod Lunella coronata (19 ind. m-2, 21%) were at low densities.
3.6.53
In general, there was no consistent
zonation pattern of species distribution observed across
all sampling zones and tidal levels. The species distribution should
be determined by the type of substratum
primarily. In general, gastropods Batillaria multiformis
(total number of individuals: 3864 ind.,
relative abundance 32.9%), Cerithidea djadjariensis (1103 ind., 9.4%) and Batillaria zonalis (713 ind., 6.1%) were the most commonly occurring
species on sandy and soft mud substrata. Rock oyster Saccostrea cucullata (2263 ind., 19.3%), gastropods Monodonta labio
(1706 ind., 14.5%) were commonly
occurring species inhabiting gravel
and boulders substratum.
Biodiversity and abundance of soft shore
communities
3.6.54
Table 3.7 of Appendix O shows the mean values of species number,
density, biodiversity index H¡¦ and species evenness
J of soft shore
communities at every tidal level and in every sampling
zone. Among the sampling zones, there was no clear difference on mean species
number (7-9 spp. 0.25 m-2), mean H¡¦
(1.2-1.5) and mean J (0.5-0.7). The
mean density of TC1 (545 ind. m-2) was higher than other sampling
zones (308-398 ind. m-2).
3.6.55
Across
the tidal levels, there was no consistent difference of the mean number of
species, H¡¦ and J in all sampling zones. For the mean density, a general decreasing
trend was observed from high to low tidal level at TC1, TC2 and ST. As
mentioned, the variation of mean density should be determined by the
type of substratum primarily.
3.6.56
Figures 3.11 to 3.14 of Appendix O show
the temporal changes of mean number of species, mean
density, H¡¦ and J at every tidal level and in
every sampling zone along the sampling months. Overall no
consistent temporal change of any biological parameters was observed. All the
parameters were under slight and natural fluctuation with the seasonal
variation.
Impact of the HKLR project
3.6.57
The
present survey was the 14th 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
Solid and Liquid Waste Management Status
3.7.1
The Contractor registered with EPD as a Chemical
Waste Producer on 12 July 2012 for the Contract. Sufficient numbers of
receptacles were available for general refuse collection and sorting.
3.7.2
The summary of waste flow table is detailed in Appendix
K.
3.7.3
The Contractor was reminded that chemical waste
containers should be properly treated and stored temporarily in designated
chemical waste storage area on site in accordance with the Code of Practice on
the Packaging, Labelling and Storage of Chemical Wastes.
3.8
Environmental Licenses and Permits
3.8.1
The valid environmental licenses and permits
during the reporting period are summarized in Appendix L.
4
Environmental Complaint and Non-compliance
4.1.1 The detailed air quality, noise, water
quality and dolphin exceedances are provided in Appendix M. Also, the summaries of the
environmental exceedances are presented as follows:
Air Quality
4.1.2 There were no Action and Limit Level exceedances of 1-hr TSP and 24-hour
TSP were recorded at AMS5 and AMS6 during the reporting period.
Noise
4.1.3 There were no Action/Limit Level exceedances
for noise during daytime on normal weekdays of the reporting period.
Water Quality
4.1.4 For marine water quality monitoring, no Action Level
and Limit Level exceedances of turbidity level, dissolved oxygen level and
suspended solid level were recorded during the reporting period.
Dolphin
4.1.5
There was one Limit Level exceedance of dolphin monitoring for the
quarterly monitoring data (between March 2016 ¡V May 2016). According to the
contractor¡¦s information, the marine activities undertaken for HKLR03 during
the quarter of March 2016 ¡V May 2016 included removal of surcharge materials,
temporary drainage diversion, ground investigation and maintenance of silt
curtain.
4.1.6 There is no evidence
showing the current LL non-compliance directly related to the construction
works of HKLR03 (where the amounts of working vessels for HKLR03 have been
decreasing), although the generally increased amount of vessel traffic in NEL
during the impact phase has been partly contributed by HKLR03 works since
October 2012. It should also be noted that 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 (CWD). In addition, the contractor will
implement proactive mitigation measures such as avoiding anchoring at Marine
Department¡¦s designated anchorage site ¡V Sham Shui Kok Anchorage (near Brothers
Island) as far as practicable.
4.1.7 All dolphin protective measures
are fully and properly implemented in accordance with the EM&A Manual.
According to the Marine Travel Route Plan, the travelling speed of vessels must
not exceed 5 knots when crossing the edge of the proposed marine park. The
Contractor will continue to provide training for skippers to ensure that their
working vessels travel from source to destination to minimize impacts on
Chinese White Dolphin and avoid anchoring at Marine Department¡¦s designated
anchorage site - Sham Shui Kok Anchorage (near Brothers Island) as far as
practicable. Also, it is recommended to complete the marine works of the
Contract as soon as possible so as to reduce the overall duration of impacts
and allow the dolphins population to recover as early as possible.
4.2
Summary of Environmental Complaint, Notification of
Summons and Successful Prosecution
4.2.1
There were no complaints
received during the reporting period. The details of cumulative
statistics of Environmental Complaints are provided in Appendix
N.
4.2.2
No notification of
summons and prosecution was received during the reporting period.
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:
¡P
The
Contractor was reminded to cover stockpile of more than 20 bags of cement with
impervious sheeting at N1 and A2 Bridge.
¡P
The
Contractor was reminded to cover the stockpile of sand at A2 Bridge.
¡P
The
Contractor was reminded to provide maintenance for the vessel to avoid dark
smoke emission at S7.
¡P
The
Contractor was reminded to provide water spraying for the rock breaking
activity at S15.
¡P
The
Contractor was reminded to utilize the dust screen of the drilling rig at S16.
¡P
The
Contractor was reminded to remove the dusty materials at the road side of S25.
¡P
The
Contractor was reminded to close the mechanical cover of the dump truck during
transportation of fill materials at S25.
¡P
The
Contractor was reminded to cover the stockpile of dusty fill material at N30.
¡P
The
Contractor was reminded to align the silt curtain properly/ close the openings
at Portion X.
¡P
The
Contractor was reminded to fill in the gap for silt curtains at Portion X and
HMA.
¡P
The
Contractor was reminded to provide proper protection along seafront at S7 to
avoid dropping of silt and debris into the sea.
¡P
The
Contractor was reminded to pump out the water inside the concrete truck washing
bay for proper wastewater treatment at S7.
¡P
The
Contractor was reminded to replace the broken sand bags at S7.
¡P
The
Contractor was reminded to repair the water pump of the automatic wheel wash
system at S7.
¡P
The
Contractor was reminded to rectify the wheel washing bay at S9.
¡P
The
Contractor was reminded to indicate the source of discharge pipes on the pipes
at S15.
¡P
The
Contractor was reminded to maintain the wastewater treatment facility at S23
and properly treat all the wastewater before discharge.
¡P
The
Contractor was reminded to provide sand bags along the site boundary next to
the road in order prevent runoff onto the public roads at S25.
¡P
The
Contractor was reminded to identify and mark the source of discharge pipe at
the outlet at S25.
¡P
The
Contractor was reminded to stop the leakage from the waste water treatment
facility immediately at N26.
¡P
The
Contractor was reminded to sign the checklist for checking wastewater treatment
facilities after inspection immediately at N26.
¡P
The
Contractor was reminded to place sand bags around the gully and provide an
adequate wheel washing facility at N30.
¡P
The
Contractor was reminded to provide proper protection along PR9 to avoid muddy
runoff entering into the sea.
¡P
The
Contractor was reminded to direct the discharge to the approved discharge point
at PR10.
¡P
The
Contractor was reminded to clean up the scum and block the abandon discharge
pipe if it is not in use at PR10.
¡P
The
Contractor was reminded to provide proper treatment for all wastewater
generated from the site prior to discharge at PR10.
¡P
The
Contractor was reminded to provide drip trays for chemicals at S7, S11, HMA,
N1, N20, West Portal and Portion X.
¡P
The
Contractor was reminded to remove/clean up the oil stain at N26 and S11.
¡P
The
Contractor was reminded to provide proper labels for oil drums/ chemical
containers at S11, N26 and West Portal.
¡P
The
Contractor was reminded to remove the leakage and proper maintain the machinery
at West Portal.
¡P
The
Contractor was reminded to remove the accumulated waste at S8, S11, S15, S16,
S23, S25, WA6, HMA, N1, N26 and West Portal.
¡P
The
Contractor was reminded to remove the rubbish inside the rubbish bin regularly
at WA6.
¡P
The
Contractor was reminded to collect the empty chemical containers and disposal
of through a licenced chemical waste collector at S8.
¡P
The
Contractor was reminded to sort the filling materials before reclamation to
reduce silty material content at S25.
¡P
The
Contractor was reminded to remove the stagnant water at A2 Bridge, S7, S8, S11,
S15, S23, S25, HMA PR9, West Portal and ventilation building to avoid mosquito
breeding.
¡P
The
Contractor was reminded to remove stagnant water inside the blocked U channel
at N26.
¡P
The
Contractor was reminded to level the road to avoid accumulation of water at
S11.
¡P
The
Contractor was reminded to fill the water pits to avoid accumulation of water
at S11.
¡P
The
Contractor was reminded to remove the stagnant water inside the H-beam at S8.
¡P
The
Contractor was reminded to remove the materials from the trees at S9.
5.2.1
The
impact monitoring programme for air quality, noise, water quality and dolphin
ensured that any deterioration in environmental condition was readily detected
and timely actions taken to rectify any non-compliance. Assessment and analysis
of monitoring results collected demonstrated the environmental impacts of the
contract. With implementation of the recommended environmental mitigation
measures, the contract¡¦s environmental impacts were considered environmentally
acceptable. The weekly environmental site inspections ensured that all the
environmental mitigation measures recommended were effectively implemented.
5.2.2 The recommended environmental mitigation
measures, as included in the EM&A programme, effectively minimize the
potential environmental impacts from the contract. Also, the EM&A programme
effectively monitored the environmental impacts from the construction
activities and ensure the proper implementation of mitigation measures. No particular
recommendation was advised for the improvement of the programme.
5.3.1
The construction phase and EM&A programme of
the Contract commenced on 17 October 2012. This is the fifteenth Quarterly EM&A
Report which summarizes the monitoring results and audit findings of the
EM&A programme during the reporting period from 1 March 2016 to 31 May 2016.
Air Quality
5.3.2
There were no Action and
Limit Level exceedances of 1-hr TSP and 24-hour TSP were recorded at AMS5 and
AMS6 during the reporting period.
Noise
5.3.3
There
were no Action/Limit Level exceedances for noise during daytime on normal
weekdays of the reporting period.
Water Quality
5.3.4
For marine water quality
monitoring, no Action Level and Limit
Level exceedances of turbidity level, dissolved oxygen level and suspended
solid level were recorded during the reporting period.
Dolphin
5.3.5
There
was a Limit Level exceedance of dolphin monitoring for the quarterly monitoring
data (between March 2016 ¡V May 2016).
5.3.6
During this quarter of dolphin monitoring, no
adverse impact from the activities of this construction project on Chinese
White Dolphins was noticeable from general observations.
5.3.7
Although 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 since
2012, and many individuals have shifted away from the important habitat around
the Brothers Islands.
5.3.8
It is critical to continuously 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
5.3.9
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
5.3.10
The March 2016 survey was the fourteenth 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, seagrass
and intertidal soft shore community.
Environmental Site Inspection and Audit
5.3.11 Environmental
site inspection was carried out on 3, 9, 16, 23 and
29 March 2016; 6, 14, 20 and 29 April 2016; and 4, 11, 18 and 27 May
2016. Recommendations on remedial actions were given to the Contractors for the
deficiencies identified during the site inspections.
5.3.12
There
were no complaints received in relation to the environmental impacts during the
reporting period.
5.3.13
No notification of summons and prosecution was
received during the reporting period.